Enhanced Bioreclamation of Jet Fuels: A Full-Scale Test at Eglin AFB, Florida
1989-09-01
accelerated fuel degradation. To the authors’ knowledge , in the United States only one relatively undocumented attempt at nitrate utilization has...site demonstrations. To the authors’ knowledge . only the nitrate demonstrations previously discussed have been attempted to clean tip fuel...authors* knowledge -, enhanced bioreclamation is the only demonstrated technology for in situ treatment of hydrocarbons in deeper groundwaters. 5
Recent trends at the state and federal level in accelerating CERCLA clean-ups
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clegg, B.
Efforts at accelerating remedial action at the federal level focus on the following: the Superfund accelerated clean-up model (SCAM); Brownfields economic redevelopment initiative; guidance documents and policies; and collaboration with state voluntary cleanup programs. At the state level efforts involved in accelerating clean-ups include voluntary clean-up programs and Brownfields initiatives.
Vroblesky, D.A.; Petkewich, M.D.; Lowery, M.A.; Landmeyer, J.E.
2011-01-01
Groundwater contamination by tetrachloroethene and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry-cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former above-ground storage tanks. Free-phase tetrachloroethene from activities in this area entered the groundwater. The southern plume originates at a nearby, new dry-cleaning facility, but probably was the result of contamination released to the aquifer from a leaking sanitary sewer line from the former dry-cleaning facility. Discharge of dissolved groundwater contamination is primarily to leaking storm sewers below the water table. The strong influence of sanitary sewers on source distribution and of storm sewers on plume orientation and discharge at this site indicates that groundwater-contamination investigators should consider the potential influence of sewer systems at their sites. ?? 2011, National Ground Water Association.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1987-05-01
This document reports on the activities of States in FY 85 and 86 in developing and implementing State ground-water protection strategies using Clean Water Act Section 106 funds. Every State and all but one territory has participated in the program. Strategies have included emphasis on the need to consolidate State and local agency efforts, and to provide clear policy direction, greater public awareness and education concerning ground-water protection.
April 2016 Pacific Southwest Newsletter
EPA Pacific Southwest Newsletter for April 2016: University of Arizona Reduces Food Waste, Cleaning Up Underground Fuel Tanks in Fresno, The Argonaut Mine, Ensuring Clean Water in Nevada,Cleaning Up Groundwater in Whittier, California, and more!
Arsenic Remediation Enhancement Through Chemical Additions to Pump and Treat Operations
NASA Astrophysics Data System (ADS)
Wovkulich, K.; Mailloux, B. J.; Stute, M.; Simpson, H. J.; Keimowitz, A. R.; Powell, A.; Lacko, A.; Chillrud, S. N.
2008-12-01
Arsenic is a contaminant found at more than 500 US Superfund sites. Since pump and treat technologies are widely used for remediation of contaminated groundwater, increasing the efficiency of contaminant removal at such sites should allow limited financial resources to clean up more sites. The Vineland Chemical Company Superfund site is extensively contaminated with arsenic after waste arsenic salts were stored and disposed of improperly for much of the company's 44 year manufacturing lifetime. Despite approximately eight years of pump and treat remediation, arsenic concentrations in the recovery wells can still be greater than 1000 ppb. The arsenic concentrations in the groundwater remain high because of slow desorption of arsenic from contaminated aquifer solids. Extrapolation of laboratory column experiments suggest that continuing the current groundwater remediation practice based on flushing ambient groundwater through the system may require on the order of hundreds of years to clean the site. However, chemical additions of phosphate or oxalic acid into the aquifer could decrease the remediation time scale substantially. Laboratory results from a soil column experiment using input of 10 mM oxalic acid suggest that site clean up of groundwater could be decreased to as little as four years. Pilot scale forced gradient field experiments will help establish whether chemical additions can be effective for increasing arsenic mobilization from aquifer solids and thus substantially decrease pump and treat clean up time.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Powell, J.; Johnston, F.; Homer, J.
2008-07-01
At both the Fernald Preserve and the Weldon Spring Site, the development of ecological restoration goals and objectives was used to complement and even enhance achievement of selected remedies. Warm-season native grasses and forbs were used for revegetation of remediated areas. The hardiness and ability to establish in low-nutrient conditions make native grasses ideal candidates for reestablishment of vegetation in excavated areas. At the Fernald Preserve, native grasses were used for vegetative cover on an on-site disposal facility as well. Also at the Fernald Preserve, excavation footprints were optimized to increase the quantity and quality of created wetlands. Drainage featuresmore » in a couple instances provide passive groundwater recharge, potentially accelerating groundwater remediation efforts. In addition, a number of clean materials and structures were beneficially reused as part of ecological restoration designs, including wood-chip mulch and woody debris, clean concrete, and a rail trestle. At the Weldon Spring Site, several methods were used to control erosion for three years after the initial seeding of native species. A field evaluation of soil conditions and general species diversity was performed in 2007 and it was determined that erosion at the site was typical and repairing naturally. These approaches resulted in 'win-win' strategies needed to successfully remediate and restore complex projects such as the Fernald Preserve and Weldon Spring. (authors)« less
Groundwater and organic chemicals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dawson, H.E.
1995-12-01
Groundwater is a major source of drinking water for many communities. Unfortunately, organic chemicals such as dry cleaning fluids, solvent, fuels, and pesticides have contaminated groundwater in many areas, rendering the groundwater useless as a drinking water resource. In many cases, the groundwater cannot be cleaned up with current technologies, particularly if the groundwater has been contaminated with immiscible (low solubility) organic liquids. In this talk, I will describe the path I have followed from geologist to geochemist and finally to environmental engineer. As a geologist, I studied the chemistry of rock metamorphosis. As a geochemist, I explored for goldmore » and other metals. Now as an environmental engineer, I investigate the behavior of organic liquids in the subsurface. While these fields all appear very different, in reality I have always focused on the interaction of rocks or sediments with the fluids with which they come in contact.« less
Machackova, Jirina; Wittlingerova, Zdena; Vlk, Kvetoslav; Zima, Jaroslav
2012-01-01
Biodegradation of petroleum hydrocarbons (TPH), mainly jet fuel, had taken place at the former Soviet Army air base in the Czech Republic. The remediation of large-scale petroleum contamination of soil and groundwater has provided valuable information about biosparging efficiency in the sandstone sedimentary bedrock. In 1997 petroleum contamination was found to be present in soil and groundwater across an area of 28 hectares, divided for the clean-up purpose into smaller clean-up fields (several hectares). The total estimated quantity of TPH released to the environment was about 7,000 metric tons. Biosparging was applied as an innovative clean-up technology at the site and was operated over a 10-year period (1997-2008). Importance of a variety of factors that affect bacterial activity in unsaturated and saturated zones was widely studied on the site and influence of natural and technological factors on clean-up efficiency in heavily contaminates areas of clean-up fields (initial contaminant mass 111-452 metric ton/ha) was evaluated. Long-term monitoring of the groundwater temperature has shown seasonal rises and falls of temperature which have caused a fluctuation in biodegradation activity during clean-up. By contrast, an overall rise of average groundwater temperature was observed in the clean-up fields, most probably as a result of the biological activity during the clean-up process. The significant rise of biodegradation rates, observed after air sparging intensification, and strong linear correlation between the air injection rates and biodegradation activities have shown that the air injection rate is the principal factor in biodegradation efficiency in heavily contaminated areas. It has a far more important role for achieving a biodegradation activity than the contamination content which appeared to have had only a slight effect after the removal of about 75% of initial contamination.
Groundwater in Science Education
ERIC Educational Resources Information Center
Dickerson, Daniel L.; Penick, John E.; Dawkins, Karen R.; Van Sickle, Meta
2007-01-01
Although clean, potable groundwater constitutes one of our most valuable resources, few students or science educators hold complete and appropriate understandings regarding the concept. Recent studies that focus on secondary students' and preservice science teachers' understandings of groundwater found little difference between the groups'…
ERIC Educational Resources Information Center
Cole, Charles A.
Described is a presentation and learning session on groundwater, which is intended to educate advisory groups interested in improving water quality decision making. Among the areas addressed are the importance of groundwater, sources of contamination, and groundwater pollution control programs. These materials are part of the Working for Clean…
40 CFR 192.04 - Corrective action.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Corrective action. If the groundwater concentration limits established for disposal sites under provisions of..., in any case, as a minimum shall: (a) Conform with the groundwater provisions of § 192.02(c)(3), and (b) Clean up groundwater in conformance with subpart B, modified as appropriate to apply to the...
40 CFR 192.04 - Corrective action.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Corrective action. If the groundwater concentration limits established for disposal sites under provisions of..., in any case, as a minimum shall: (a) Conform with the groundwater provisions of § 192.02(c)(3), and (b) Clean up groundwater in conformance with subpart B, modified as appropriate to apply to the...
Fort Ord Groundwater Remediation Studies, 2002 - 2005
2006-08-01
Groundwater was also directly sampled from a well OU1-36 with a bailer using an acid - cleaned bailer to determine whether comparable levels of trace...collected for the analysis of total chromium. The total chromium and Cr(VI) samples were collected in acid -clean low density polyethylene (LDPE) bottles...and 69Ga to be used as an internal standard. Acetic acid /ammonia buffer solution was prepared by slow addition of 15 mL of aqueous ammonia (20–22
Chemistry and microbiology of permeable reactive barriers for in situ groundwater clean up.
Scherer, M M; Richter, S; Valentine, R L; Alvarez, P J
2000-01-01
Permeable reactive barriers (PRBs) are receiving a great deal of attention as an innovative, cost-effective technology for in situ clean up of groundwater contamination. A wide variety of materials are being proposed for use in PRBs, including zero-valent metals (e.g., iron metal), humic materials, oxides, surfactant-modified zeolites (SMZs), and oxygen- and nitrate-releasing compounds. PRB materials remove dissolved groundwater contaminants by immobilization within the barrier or transformation to less harmful products. The primary removal processes include: (1) sorption and precipitation, (2) chemical reaction, and (3) biologically mediated reactions. This article presents an overview of the mechanisms and factors controlling these individual processes and discusses the implications for the feasibility and long-term effectiveness of PRB technologies.
Hele-Shaw Experiments on Plume Stretching and Folding
NASA Astrophysics Data System (ADS)
Foster, M.; Mays, D. C.; Neupauer, R. M.
2013-12-01
Fluid mixing in laminar flow is important in a number of practical applications, including remediation of contaminated groundwater. Recent modeling studies have shown that mixing can be accelerated and amplified by imposing a flow that generates stretching and folding of an injected plume of treatment solution. Stretching and folding, in turn, results from engineered injection and extraction of clean water through an array of wells surrounding the treatment solution. This poster describes a series of experiments whose goal is to demonstrate plume stretching and folding in a Hele-Shaw apparatus. An initial plume of treatment solution is injected into the center of the Hele-Shaw apparatus, which is assumed to represent a zone of contaminated groundwater, with four wells spaced evenly around the treatment solution. In order to spread the treatment solution into the groundwater, the four wells perform a series of infusions and withdrawals that push and pull apart the plume of treatment solution. With the proper steps, it will be shown that the plume can be stretched and folded to greatly increase the reactive interface area between the treatment solution and the contaminated groundwater. Consideration is given to two qualitative differences with respect to previous modeling studies. First, constant volume is required by the no-flow boundary used at the edge of the Hele-Shaw cell; any pump that is withdrawing water must have a complementary pump adding water at the same rate. Second, in these experiments, mixing results from a physical process, namely Taylor dispersion, eliminating the uncertainty resulting from the need to assume dispersion mechanisms in numerical models. Therefore, these experiments further elucidate the benefits and challenges of imposing plume stretching and folding in systems (like aquifers) where dispersion is unavoidable, providing new insight into the required logistics of using this approach in groundwater treatment.
Application of step-drawdown test for planning agricultural groundwater well maintenance in S. Korea
NASA Astrophysics Data System (ADS)
Song, Sung-Ho; Lee, Byung-Sun
2015-04-01
Well efficiency decreases with time after development and the pumping rate is reduced sharply at a certain point. However, the rapid decrease of the efficiency definitely depends upon the physical characteristics of the aquifer, chemical properties of groundwater, pore clogging by adsorptive/precipitable materials, and use of groundwater well. In general, it is expected that an adequate and ongoing maintenance for the well is effective in extension of operating periods because major maintenance frequency requirement at municipal wells placed in the crystalline rock aquifer is known to be relatively longer. The proportion of agricultural wells (583,748) against the total groundwater ones (1,380,715) is 42.3% in 2011, S. Korea. Groundwater use accounts for 1.9 billion m3/year which indicates 48.9% of total amount available groundwater resources. Approximate 69% of the total agricultural public wells placed in crystalline rock aquifer have passed more than 10 years after development. In this study, the increase of well efficiency before and after the well disinfection/cleaning for agricultural groundwater wells in the mountains, plains, and coastal aquifer with the data of step-drawdown test was evaluated, respectively. With the concept of critical yield, the increase of available amount of groundwater was quantitatively analyzed after treatment. From the results, well efficiency increased approximately 1.5 to 4 times depending on pumping rate when the proper disinfection/cleaning methods to the wells were applied. In addition, it showed that the pumping rate of approximate 4-8% with the critical yield from step-drawdown test increased and these effects were the highest in wells which are more than 10 years elapsed. Therefore, it would be concluded that the well disinfection/cleaning methods for the purpose of increasing the efficiency are more effective for the wells that are older than 10 years.
Abrasive blast cleaning method for the renewal of worn-out acceleration tubes
NASA Astrophysics Data System (ADS)
Bartha, L.; Koltay, E.; Mórik, Gy.
1996-04-01
The degradation of the electrical properties of acceleration tubes emerging with performance time is known to be assigned mainly to impurities and surface breakdown tracks appearing on the inner surface of the insulators. Consequently, a radical treatment for removing the surface layer may result in a renewal of the tube. An abrasive blast cleaning procedure has been used on a set of worn-out acceleration tube units. The cleaned tube exhibited its original electrical characteristics and it has been used for more than 4000 h of operation up to the maximum rated voltage of our 5 MV electrostatic accelerator without any observable degradation. XRF and PIXE analytical measurements performed on used and blast-treated insulators as well as on electrode and pump oil samples reveal the contribution of elementary processes in the acceleration tube to the ageing of the tube and indicate the effectness of the blasting process used for the re-establishment of clean surface conditions.
Sustainable solar energy capability studies by using S2H model in treating groundwater supply
NASA Astrophysics Data System (ADS)
Musa, S.; Anuar, M. F.; Shahabuddin, M. M.; Ridzuan, M. B.; Radin Mohamed, R. M. S.; Madun, M. A.
2018-04-01
Groundwater extracted in Research Centre for Soft Soil Malaysia (RECESS) contains a number of pollutants that exceed the safe level for consumption. A Solar-Hydro (S2H) model which is a practical prototype has been introduced to treat the groundwater sustainably by solar energy process (evaporation method). Selected parameters was tested which are sulphate, nitrate, chloride, fluoride, pH and dissolved oxygen. The water quality result shows that all parameters have achieved 100% of the drinking water quality standard issued by the Ministry of Health Malaysia. Evaporation method was proven that this solar energy can be applied in sustainably treating groundwater quality with up to 90% effectiveness. On the other hand, the quantitative analysis has shown that the production of clean water is below than 2% according to time constraints and design factors. Thus, this study can be generate clean and fresh water from groundwater by using a simplified model and it has huge potential to be implemented by the local communities with a larger scale and affordable design.
CHARACTERIZATION OF FRACTURED BEDROCK FOR STEAM INJECTION
The most difficult setting in which to conduct groundwater remediation is that where chlorinated solvents have penetrated fractured bedrock. To demonstrate the potential viability of steam injection as a means of groundwater clean-up in this type of environment, steam will be in...
PHYTOREMEDIATION: USING PLANTS TO CLEAN UP CONTAMINATED SOIL, GROUNDWATER, AND WASTEWATER
Phytoremediation is an emerging cleanup technology for contaminated soils, groundwater, and wastewater that is both low-tech and low-cost. The cleanup technology is defined as the use of green plants to remove, contain, or render harmless such environmental contaminants as heavy ...
Solutions Remediate Contaminated Groundwater
NASA Technical Reports Server (NTRS)
2010-01-01
During the Apollo Program, NASA workers used chlorinated solvents to clean rocket engine components at launch sites. These solvents, known as dense non-aqueous phase liquids, had contaminated launch facilities to the point of near-irreparability. Dr. Jacqueline Quinn and Dr. Kathleen Brooks Loftin of Kennedy Space Center partnered with researchers from the University of Central Florida's chemistry and engineering programs to develop technology capable of remediating the area without great cost or further environmental damage. They called the new invention Emulsified Zero-Valent Iron (EZVI). The groundwater remediation compound is cleaning up polluted areas all around the world and is, to date, NASA's most licensed technology.
The aim of the model was to forecast the groundwater mercury pollution distribution aureole and to discuss the mathematical simulations of the estimated quantity of mercury entering the river Irtysh and the aquifer wells in the village of Pavlodarskoe. During the years of 1975-1...
Regional strategies for the accelerating global problem of groundwater depletion
NASA Astrophysics Data System (ADS)
Aeschbach-Hertig, Werner; Gleeson, Tom
2012-12-01
Groundwater--the world's largest freshwater resource--is critically important for irrigated agriculture and hence for global food security. Yet depletion is widespread in large groundwater systems in both semi-arid and humid regions of the world. Excessive extraction for irrigation where groundwater is slowly renewed is the main cause of the depletion, and climate change has the potential to exacerbate the problem in some regions. Globally aggregated groundwater depletion contributes to sea-level rise, and has accelerated markedly since the mid-twentieth century. But its impacts on water resources are more obvious at the regional scale, for example in agriculturally important parts of India, China and the United States. Food production in such regions can only be made sustainable in the long term if groundwater levels are stabilized. To this end, a transformation is required in how we value, manage and characterize groundwater systems. Technical approaches--such as water diversion, artificial groundwater recharge and efficient irrigation--have failed to balance regional groundwater budgets. They need to be complemented by more comprehensive strategies that are adapted to the specific social, economic, political and environmental settings of each region.
77 FR 3836 - Supplemental Environmental Impact Statement, Mingo County, WV
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-25
... Mountain Surface Mine Clean Water Act Section 404 Permit Application. The FHWA and USACE are joint-lead... 2000 FEIS and approved in the 2000 ROD. The USACE is evaluating a Clean Water Act (CWA) Section 404... to surface water and groundwater resources, including aquatic habitat, water quantity and quality...
NASA Technical Reports Server (NTRS)
Fischer, Holger
2009-01-01
NASA's White Sands Test Facility has six core environmental compliance capabilities: remote hazardous testing of reactive, explosive and toxic materials and fluids; hypergolic fluids materials and systems testing; oxygen materials and system testing; hypervelocity impact testing; flight hardware processing; and, propulsion testing. The facility's permit status and challenges are reviewed. Historic operations and practices dating from the 1960s through the early 1980s resulted in contamination of the facility's groundwater. An environmental restoration effort has been employed to protect public health and the health of the workforce. The restoration seeks to properly handle hazardous materials and waste processes; determine the nature and extent of the contamination; stop the migration of contaminated groundwater; stabilize the plume front which has been assessed as the greatest risk to public health; and, clean-up the environment to restore it to preexisting conditions. The Plume Front Treatment System is operational and seeks to stop the westward movement of the plume to protect drinking water and irrigation well. Specifically, the treatment system will extract contaminated water from the aquifer, remove chemical using the best available technology, and return (inject) the treated water back to the aquifer. The Mid-Plume Interception Treatment System also seeks to stop the migration of containment, as well as to evaluate new technologies to accelerate cleanup, such as bioremediation.
Vroblesky, Don A.; Petkewich, Matthew D.; Landmeyer, James E.; Lowery, Mark A.
2009-01-01
Groundwater contamination by tetrachloroethene and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry-cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former above-ground storage tanks. Free-phase tetrachloroethene from activities in this area entered the groundwater and the storm sewer. The southern plume originates at a nearby new dry-cleaning facility, but probably was the result of contamination released to the aquifer from a leaking sanitary sewer line from the former dry-cleaning facility. Discharge of dissolved groundwater contamination is primarily to leaking storm sewers below the water table. Extensive biodegradation of the contamination takes place in the surficial aquifer; however, the biodegradation is insufficient to reduce trichloroethene to less than milligram-per-liter concentrations prior to discharging into the storm sewers. The groundwater volatile organic compounds entering the storm sewers are substantially diluted by tidal flushing upon entry and are subject to volatilization as they are transported through the storm sewer to a discharge point in a tributary to Ballast Creek. TCE concentrations of about 2-6 micrograms per liter were present in storm-sewer water near the discharge point (sampled at manhole STS26). On three out of four sampling events at manhole STS14, the storm-sewer water contained no vinyl chloride. During a time of relatively high groundwater levels, however, 20 micrograms per liter of vinyl chloride was present in STS14 storm-sewer water. Because groundwater leaks into that storm sewer and because the storm sewer upgradient from manhole STS14 is adjacent to part of the aquifer where 2,290 micrograms per liter of vinyl chloride have been detected, there is a potential for substantially increased concentrations of vinyl chloride to discharge at the storm-sewer outfall under conditions of high groundwater levels and low tidal flushing. In addition, the observation that free-phase tetrachloroethene may have entered the storm-sewer system during the 1994 discharge means that dense nonaqueous phase liquid tetrachloroethene could have leaked from various parts of the storm sewer or discharged to surface water at the storm-sewer outfall.
Machining and brazing of accelerating RF cavity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghodke, S.R.; Barnwal, Rajesh; Mondal, Jayant, E-mail: ghodke_barc@yahoo.co.in
2014-07-01
BARC has developed 2856 MHz accelerating cavities for 6 MeV, 9 MeV and 10 MeV RF Linac. New vendors are developed for mass production of accelerating cavity for future projects. New vendors are developing for diamond turning machining, cleaning and brazing processes. Fabrication involved material testing, CNC diamond turning of cavity, cavity cleaning and brazing. Before and after brazing resonance frequency (RF) of cavity was checked with vector network analyser (VNA). A power feed test setup is also fabricated to test power feed cavity before brazing. This test setup will be used to find out assembly performance of power feedmore » cavity and its coupler. This paper discusses about nano machining, cleaning and brazing processes of RF cavities. (author)« less
Helping Research Organizations Build a Clean Energy Future | Working with
Us | NREL Helping Research Organizations Build a Clean Energy Future Helping Research Organizations Build a Clean Energy Future Partner with NREL to accelerate the research and development of your
NASA Astrophysics Data System (ADS)
Mouser, P. J.; Rizzo, D. M.; Druschel, G.; O'Grady, P.; Stevens, L.
2005-12-01
This interdisciplinary study integrates hydrochemical and genome-based data to estimate the redox processes occurring at long-term monitoring sites. Groundwater samples have been collected from a well-characterized landfill-leachate contaminated aquifer in northeastern New York. Primers from the 16S rDNA gene were used to amplify Bacteria and Archaea in groundwater taken from monitoring wells located in clean, fringe, and contaminated locations within the aquifer. PCR-amplified rDNA were digested with restriction enzymes to evaluate terminal restriction fragment length polymorphism (T-RFLP) community profiles. The rDNA was cloned, sequenced, and partial sequences were matched against known organisms using the NCBI Blast database. Phylogenetic trees and bootstrapping were used to identify classifications of organisms and compare the communities from clean, fringe, and contaminated locations. We used Artificial Neural Network (ANN) models to incorporate microbial data with hydrochemical information for improving our understanding of subsurface processes.
Storck, Florian R; Schmidt, Carsten K; Wülser, Richard; Brauch, Heinz-Jürgen
2012-01-01
Drinking water is often produced from surface water by riverbank filtration (RBF) or artificial groundwater recharge (AGR). In this study, an AGR system was exemplarily investigated and results were compared with those of RBF systems, in which the effects of redox milieu, temperature and surface water discharge on the cleaning efficiency were evaluated. Besides bulk parameters such as DOC (dissolved organic carbon), organic trace pollutants including iodinated X-ray contrast media, personal care products, complexing agents, and pharmaceuticals were investigated. At all studied sites, levels of TOC (total organic carbon), DOC, AOX (adsorbable organic halides), SAC (spectral absorption coefficient at 254 nm), and turbidity were reduced significantly. DOC removal was stimulated at higher groundwater temperatures during AGR. Several substances were generally easily removable during both AGR and RBF, regardless of the site, season, discharge or redox regime. For some more refractory substances, however, removal efficiency turned out to be significantly influenced by redox conditions.
Containment of fertilizers and pesticides at retail operations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broder, M.F.
1990-06-28
Environmental protection has become as important to the fertilizer retailer as the products and services he offers. Emphasis on environmental protection at the dealer level is largely in response to state regulations designed to protect groundwater. The national Clean Water Act of 1987 gave states the lead in developing groundwater protection strategies. Several states have adopted new or stronger regulations and others are moving to do so. Fertilizer dealers need to keep up with these regulations and promote groundwater protection. This paper describes several containment systems for fertilizers and pesticides to help dealers decide how to modify their plants tomore » protect groundwater.« less
Implementation Science to Accelerate Clean Cooking for Public Health
Rosenthal, Joshua; Balakrishnan, Kalpana; Bruce, Nigel; Chambers, David; Graham, Jay; Jack, Darby; Kline, Lydia; Masera, Omar; Mehta, Sumi; Mercado, Ilse Ruiz; Neta, Gila; Pattanayak, Subhrendu; Puzzolo, Elisa; Petach, Helen; Punturieri, Antonello; Rubinstein, Adolfo; Sage, Michael; Sturke, Rachel; Shankar, Anita; Sherr, Kenny; Smith, Kirk; Yadama, Gautam
2017-01-01
Summary: Clean cooking has emerged as a major concern for global health and development because of the enormous burden of disease caused by traditional cookstoves and fires. The World Health Organization has developed new indoor air quality guidelines that few homes will be able to achieve without replacing traditional methods with modern clean cooking technologies, including fuels and stoves. However, decades of experience with improved stove programs indicate that the challenge of modernizing cooking in impoverished communities includes a complex, multi-sectoral set of problems that require implementation research. The National Institutes of Health, in partnership with several government agencies and the Global Alliance for Clean Cookstoves, has launched the Clean Cooking Implementation Science Network that aims to address this issue. In this article, our focus is on building a knowledge base to accelerate scale-up and sustained use of the cleanest technologies in low- and middle-income countries. Implementation science provides a variety of analytical and planning tools to enhance effectiveness of clinical and public health interventions. These tools are being integrated with a growing body of knowledge and new research projects to yield new methods, consensus tools, and an evidence base to accelerate improvements in health promised by the renewed agenda of clean cooking. PMID:28055947
Ratio of Major Ions in Groundwater to Determine Saltwater Intrusion in Coastal Areas
NASA Astrophysics Data System (ADS)
Sudaryanto; Naily, Wilda
2018-02-01
Saltwater or seawater intrusion into groundwater aquifers occurs mostly in big cities and developing coastal cities. Coastal hydrology is associated with complex and highly dynamic environmental characteristics of interactions between groundwater, surface water, and water from the estuary. The rise of sea levels and excessive use of groundwater for clean water source trigger saltwater intrusion. Identification of saltwater intrusion into groundwater can be done by groundwater sampling and major ion analysis. The major ions dissolved in water are Ca, Mg, Na, K, Cl, HCO3, and SO4; the major ion ratios are Cl/Br, Ca/Mg, Ca/ (HCO3 and SO4), and Na/Cl. By knowing whether groundwater quality has been or has not been influenced by saltwater, groundwater zones can be determined in every coastal area. In addition, by analyzing and reviewing some concepts about the intrusion or contamination of saltwater into groundwater, there will be sufficient results for the identification of saltwater intrusion.
Estimating residents' willingness to pay for groundwater protection in the Vietnamese Mekong Delta
NASA Astrophysics Data System (ADS)
Vo, Danh Thanh; Huynh, Khai Viet
2017-03-01
Groundwater in the Vietnamese Mekong Delta is facing the pollution and it needs to be protected. Searching literature reviews on economic valuation techniques, the contingent valuation method (CVM) has been popularly applied to estimate the economic value of water protection. This approach is based on a hypothetical scenario in which respondents are requested through questionnaires to reveal their maximum willingness to pay (WTP) for the water protection project. The study used the approach of CVM to analyze the households' motivations and their WTP for the program of groundwater protection in the Mekong Delta. The study performed that the residents in the delta were willing to pay approximately 141,730 VND (US6.74) per household a year. Groundwater could be an inferior good with the negative income effect found in the demanding for clean groundwater. Respondent's gender and groundwater-related health risk consideration were factors sensitively affecting the probability of demanding for groundwater protection.
Cousins, Ian T; Vestergren, Robin; Wang, Zhanyun; Scheringer, Martin; McLachlan, Michael S
2016-09-01
Already in the late 1990s microgram-per-liter levels of perfluorooctane sulfonate (PFOS) were measured in water samples from areas where fire-fighting foams were used or spilled. Despite these early warnings, the problems of groundwater, and thus drinking water, contaminated with perfluoroalkyl and polyfluoroalkyl substances (PFASs) including PFOS are only beginning to be addressed. It is clear that this PFAS contamination is poorly reversible and that the societal costs of clean-up will be high. This inability to reverse exposure in a reasonable timeframe is a major motivation for application of the precautionary principle in chemicals management. We conclude that exposure can be poorly reversible; 1) due to slow elimination kinetics in organisms, or 2) due to poorly reversible environmental contamination that leads to continuous exposure. In the second case, which is relevant for contaminated groundwater, the reversibility of exposure is not related to the magnitude of a chemical's bioaccumulation potential. We argue therefore that all PFASs entering groundwater, irrespective of their perfluoroalkyl chain length and bioaccumulation potential, will result in poorly reversible exposures and risks as well as further clean-up costs for society. To protect groundwater resources for future generations, society should consider a precautionary approach to chemicals management and prevent the use and release of highly persistent and mobile chemicals such as PFASs. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Rahayu; Soeprobowati, Tri Retnaningsih
2018-02-01
This article aims to analyze the implementation of state obligations and responsibility ensuring the availability of clean water as part of human rights in Karimunjawa islands. The analysis based on principle of the State obligations and responsibility to fulfill their citizen right. Water sources in Karimunjawa Islands is very limited. It depend on forest conservation. Around 9.600 peoples live in Karimunjawa Islands, but Karimunjawa is non groundwater basin region. It means, Karimunjawa doesn't have groundwater potential. The quantity of water depends on the season. The solution to maintain the sustainability of clean water is piping from water reservoir to residential areas. The problem is there are so many hotels in Karimunjawa islands, it disrupted the fulfillment of clean water. Besides utilizing water from reservoir, many hotels drilled the ground to get water. It had impact to the availibity of water in dry season and affected to fulfillment of water supply for Karimunjawa people. There is no specific regulation and policy to solve this problem. Clean water management is doing by Karimunjawa's people. Meanwhile, based on Mahkamah Konstitusi Decree number 85/PUU-XI/2013, state is a rights holder to dominate the water in accordance with the Articles 33 paragraph (2) and (3) UUD NRI 1945, so the government has an obligation to make a policy, regulations, management, and supervision.
ICA-based artefact and accelerated fMRI acquisition for improved Resting State Network imaging
Griffanti, Ludovica; Salimi-Khorshidi, Gholamreza; Beckmann, Christian F.; Auerbach, Edward J.; Douaud, Gwenaëlle; Sexton, Claire E.; Zsoldos, Enikő; Ebmeier, Klaus P; Filippini, Nicola; Mackay, Clare E.; Moeller, Steen; Xu, Junqian; Yacoub, Essa; Baselli, Giuseppe; Ugurbil, Kamil; Miller, Karla L.; Smith, Stephen M.
2014-01-01
The identification of resting state networks (RSNs) and the quantification of their functional connectivity in resting-state fMRI (rfMRI) are seriously hindered by the presence of artefacts, many of which overlap spatially or spectrally with RSNs. Moreover, recent developments in fMRI acquisition yield data with higher spatial and temporal resolutions, but may increase artefacts both spatially and/or temporally. Hence the correct identification and removal of non-neural fluctuations is crucial, especially in accelerated acquisitions. In this paper we investigate the effectiveness of three data-driven cleaning procedures, compare standard against higher (spatial and temporal) resolution accelerated fMRI acquisitions, and investigate the combined effect of different acquisitions and different cleanup approaches. We applied single-subject independent component analysis (ICA), followed by automatic component classification with FMRIB’s ICA-based X-noiseifier (FIX) to identify artefactual components. We then compared two first-level (within-subject) cleaning approaches for removing those artefacts and motion-related fluctuations from the data. The effectiveness of the cleaning procedures were assessed using timeseries (amplitude and spectra), network matrix and spatial map analyses. For timeseries and network analyses we also tested the effect of a second-level cleaning (informed by group-level analysis). Comparing these approaches, the preferable balance between noise removal and signal loss was achieved by regressing out of the data the full space of motion-related fluctuations and only the unique variance of the artefactual ICA components. Using similar analyses, we also investigated the effects of different cleaning approaches on data from different acquisition sequences. With the optimal cleaning procedures, functional connectivity results from accelerated data were statistically comparable or significantly better than the standard (unaccelerated) acquisition, and, crucially, with higher spatial and temporal resolution. Moreover, we were able to perform higher dimensionality ICA decompositions with the accelerated data, which is very valuable for detailed network analyses. PMID:24657355
Griffanti, Ludovica; Salimi-Khorshidi, Gholamreza; Beckmann, Christian F; Auerbach, Edward J; Douaud, Gwenaëlle; Sexton, Claire E; Zsoldos, Enikő; Ebmeier, Klaus P; Filippini, Nicola; Mackay, Clare E; Moeller, Steen; Xu, Junqian; Yacoub, Essa; Baselli, Giuseppe; Ugurbil, Kamil; Miller, Karla L; Smith, Stephen M
2014-07-15
The identification of resting state networks (RSNs) and the quantification of their functional connectivity in resting-state fMRI (rfMRI) are seriously hindered by the presence of artefacts, many of which overlap spatially or spectrally with RSNs. Moreover, recent developments in fMRI acquisition yield data with higher spatial and temporal resolutions, but may increase artefacts both spatially and/or temporally. Hence the correct identification and removal of non-neural fluctuations is crucial, especially in accelerated acquisitions. In this paper we investigate the effectiveness of three data-driven cleaning procedures, compare standard against higher (spatial and temporal) resolution accelerated fMRI acquisitions, and investigate the combined effect of different acquisitions and different cleanup approaches. We applied single-subject independent component analysis (ICA), followed by automatic component classification with FMRIB's ICA-based X-noiseifier (FIX) to identify artefactual components. We then compared two first-level (within-subject) cleaning approaches for removing those artefacts and motion-related fluctuations from the data. The effectiveness of the cleaning procedures was assessed using time series (amplitude and spectra), network matrix and spatial map analyses. For time series and network analyses we also tested the effect of a second-level cleaning (informed by group-level analysis). Comparing these approaches, the preferable balance between noise removal and signal loss was achieved by regressing out of the data the full space of motion-related fluctuations and only the unique variance of the artefactual ICA components. Using similar analyses, we also investigated the effects of different cleaning approaches on data from different acquisition sequences. With the optimal cleaning procedures, functional connectivity results from accelerated data were statistically comparable or significantly better than the standard (unaccelerated) acquisition, and, crucially, with higher spatial and temporal resolution. Moreover, we were able to perform higher dimensionality ICA decompositions with the accelerated data, which is very valuable for detailed network analyses. Copyright © 2014 Elsevier Inc. All rights reserved.
EPA is working to develop methods and guidance to manage and clean up contaminated land, groundwater and nutrient pollution as well as develop innovative approaches to managing materials and waste including energy recovery.
Weatherization and Intergovernmental Programs Office FY 2017 Budget At-A-Glance
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2016-03-01
The Weatherization and Intergovernmental Programs (WIP) Office is part of EERE’s balanced research, development, demonstration, and deployment approach to accelerate America’s transition to a clean energy economy. WIP’s mission is to partner with state and local organizations to improve energy security and to significantly accelerate the deployment of clean energy technologies and practices by a wide range of government, community, and business stakeholders.
Supersonic gas-liquid cleaning system
NASA Technical Reports Server (NTRS)
Caimi, Raoul E. B.; Thaxton, Eric A.
1994-01-01
A system to perform cleaning and cleanliness verification is being developed to replace solvent flush methods using CFC 113 for fluid system components. The system is designed for two purposes: internal and external cleaning and verification. External cleaning is performed with the nozzle mounted at the end of a wand similar to a conventional pressure washer. Internal cleaning is performed with a variety of fixtures designed for specific applications. Internal cleaning includes tubes, pipes, flex hoses, and active fluid components such as valves and regulators. The system uses gas-liquid supersonic nozzles to generate high impingement velocities at the surface of the object to be cleaned. Compressed air or any inert gas may be used to provide the conveying medium for the liquid. The converging-diverging nozzles accelerate the gas-liquid mixture to supersonic velocities. The liquid being accelerated may be any solvent including water. This system may be used commercially to replace CFC and other solvent cleaning methods widely used to remove dust, dirt, flux, and lubricants. In addition, cleanliness verification can be performed without the solvents which are typically involved. This paper will present the technical details of the system, the results achieved during testing at KSC, and future applications for this system.
Supersonic gas-liquid cleaning system
NASA Astrophysics Data System (ADS)
Caimi, Raoul E. B.; Thaxton, Eric A.
1994-02-01
A system to perform cleaning and cleanliness verification is being developed to replace solvent flush methods using CFC 113 for fluid system components. The system is designed for two purposes: internal and external cleaning and verification. External cleaning is performed with the nozzle mounted at the end of a wand similar to a conventional pressure washer. Internal cleaning is performed with a variety of fixtures designed for specific applications. Internal cleaning includes tubes, pipes, flex hoses, and active fluid components such as valves and regulators. The system uses gas-liquid supersonic nozzles to generate high impingement velocities at the surface of the object to be cleaned. Compressed air or any inert gas may be used to provide the conveying medium for the liquid. The converging-diverging nozzles accelerate the gas-liquid mixture to supersonic velocities. The liquid being accelerated may be any solvent including water. This system may be used commercially to replace CFC and other solvent cleaning methods widely used to remove dust, dirt, flux, and lubricants. In addition, cleanliness verification can be performed without the solvents which are typically involved. This paper will present the technical details of the system, the results achieved during testing at KSC, and future applications for this system.
State Summary of Soil and Groundwater Cleanup Standards for Hydrocarbons
1993-11-15
821096-01 November 15, 1993 19970425 057 !DISTfRIBUTI STýA-TEM,_ Approved for public release; Distribution Unlbfited Product - Paranmeter/ Lab Test ...Env-mmenal Mantagemen, 20-270-5613 Product Parameter/ Lab Test Protocol Detection Notification Action Clean-up Level Constituent & Number Level Level...Envi-mnentai Managament, 205-270-.5613 Su m r of Alsk Clanu Sadr s fo Hyrcro Cotmiae Groundwater Product- - Parameter/ Lab Test Protocol ’Detection
Lee, Minhee; Yang, Minjune
2010-01-15
The uranium removal efficiencies of rhizofiltration in the remediation of groundwater were investigated in lab-scale experiments. Sunflower (Helianthus annuus L.) and bean (Phaseolus vulgaris L. var. vulgaris) were cultivated and an artificially uranium contaminated solution and three genuine groundwater samples were used in the experiments. More than 80% of the initial uranium in solution and genuine groundwater, respectively, was removed within 24h by using sunflower and the residual uranium concentration of the treated water was lower than 30 microg/L (USEPA drinking water limit). For bean, the uranium removal efficiency of the rhizofiltration was roughly 60-80%. The maximum uranium removal via rhizofiltration for the two plant cultivars occurred at pH 3-5 of solution and their uranium removal efficiencies exceeded 90%. The lab-scale continuous rhizofiltration clean-up system delivered over 99% uranium removal efficiency, and the results of SEM and EDS analyses indicated that most uranium accumulated in the roots of plants. The present results suggested that the uranium removal capacity of two plants evaluated in the clean-up system was about 25mg/kg of wet plant mass. Notably, the removal capacity of the root parts only was more than 500 mg/kg.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crowe, Tracey
2013-06-30
The Clean Energy Ministerial (CEM) is a high-level global forum to share best practices and promote policies and programs that advance clean energy technologies and accelerate the transition to a global clean energy economy. The CEM works to increase energy efficiency, expand clean energy supply, and enhance clean energy access worldwide. To achieve these goals, the CEM pursues a three-part strategy that includes high-level policy dialogue, technical cooperation, and engagement with the private sector and other stakeholders. Each year, energy ministers and other high-level delegates from the 23 participating CEM governments come together to discuss clean energy, review clean energymore » progress, and identify tangible next steps to accelerate the clean energy transition. The U.S. Department of Energy, which played a crucial role in launching the CEM, hosted the first annual meeting of energy ministers in Washington, DC, in June 2010. The United Arab Emirates hosted the second Clean Energy Ministerial in 2011, and the United Kingdom hosted the third Clean Energy Ministerial in 2012. In April 2013, India hosted the fourth Clean Energy Ministerial (CEM4) in New Delhi. Key insights from CEM4 are summarized in the report. It captures the ideas and recommendations of the government and private sector leaders who participated in the discussions on six discussion topics: reducing soft costs of solar PV; energy management systems; renewables policy and finance; clean vehicle adoption; mini-grid development; and power systems in emerging economies.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kupar, J.; Hasek, M.
The Sanitary Landfill Corrective Action Plan proposes a two pronged approach to remediation. The first part of the total remediation strategy is the placement of a RCRA style closure cap to provide source control of contaminants into the groundwater. The second part of the proposed remediation package is a phased approach primarily using an in situ bioremediation system for groundwater clean up of the Constituents of Concern (COCs) that exceed their proposed Alternate Concentration Limits (ACL). The phased in approach of groundwater clean up will involve operation of the in situ bioremediation system, followed by evaluation of the Phase 1more » system and, if necessary, additional phased remediation strategies. This document presents pertinent information on operations, well locations, anticipated capture zones, monitoring strategies, observation wells and other information which will allow a decision on the acceptability of the remedial strategy as an interim corrective action prior to permit application approval. The proposed interim phase of the remediation program will position two horizontal bioremediation wells such that the respective zones of influence will intersect the migration path for the highest concentrations of each plume.« less
Freire, T S; Aguilar, F G; Garcia, L da Fonseca Roberti; Pires-de-Souza, F de Carvalho Panzeri
2014-03-01
Acrylic resin is widely used for artificial teeth manufacturing due to several important characteristics; however, this material do not present acceptable colour stability over the course of time. This study evaluated the effect of different cleaning protocols and accelerated artificial aging on colour stability of denture teeth made of acrylic resin. Sixty denture teeth in dark and light shades were used, and separated according to the treatment to which they were submitted. Results demonstrated that colour stability of artificial teeth is influenced by the cleaning solution and artificial aging, being dark teeth more susceptible to colour alteration than lighter ones.
Isotope labeled immunoassay for environmental chemical detection
DOE Office of Scientific and Technical Information (OSTI.GOV)
Velez, M.M.
1994-05-06
Altrazine, one of the most heavily used agricultural pesticides in North America, has been identified as a major groundwater contaminant in the U.S. Research provides evidence that under certain conditions atrazine and some of its derivatives may prove to be carcinogenic and mutagenic. Immunossays are one of the most powerful of all analytical immunochemical techniques. They employ a wide range of methods to detect and quantitate antigens or antibodies, and to study the structure of antigens. With the appropriate assay, they can be remarkably quick and easy, to yield information that would be difficult to determine by other techniques. Themore » development of the appropriate assay; however, requires clean and precise separation of antigens bound to antibodies from those that remain free. Sensitive assays depend on quantification of these bound antigens at very low levels. We are making direct and competitive immunoassays with atrazine and its antibodies using accelerator mass spectrometry (AMS) in order to obtain a sensitive immunoassay for atrazine in environmental samples.« less
Submarine Groundwater Discharge in the Coastal Zone
NASA Astrophysics Data System (ADS)
Bakti, Hendra
2018-02-01
Indonesia is one of the archipelagic countries that has the longest coastline in the world. Because it is located in the tropics, in general it has a very high rainfall. Each island has a different morphology which is composed of a variety of rocks with different hydrogeological properties. This natural condition allows for the presence of groundwater in different amount in each island. The difference in groundwater hydraulics gradients in aquifer continuous to the sea has triggered the discharge of groundwater to offshore known as submarine groundwater discharge (SGD). Its presence can be as seepage or submarine springs with components derived from land and sea and a mixture between them. The understanding of SGD phenomenon is very important because it can be useful as a source of clean water in coastal areas, affecting marine health, and improving marine environment.
Aines, Roger D.; Newmark, Robin L.; Knauss, Kevin G.
2000-01-01
A thermal treatment wall emplaced to perform in-situ destruction of contaminants in groundwater. Thermal destruction of specific contaminants occurs by hydrous pyrolysis/oxidation at temperatures achievable by existing thermal remediation techniques (electrical heating or steam injection) in the presence of oxygen or soil mineral oxidants, such as MnO.sub.2. The thermal treatment wall can be installed in a variety of configurations depending on the specific objectives, and can be used for groundwater cleanup, wherein in-situ destruction of contaminants is carried out rather than extracting contaminated fluids to the surface, where they are to be cleaned. In addition, the thermal treatment wall can be used for both plume interdiction and near-wellhead in-situ groundwater treatment. Thus, this technique can be utilized for a variety of groundwater contamination problems.
Wedron Groundwater Site in Wedron, Illinois
Wedron Resource Conservation and Recovery Act (RCRA) Corrective Action program to work with hazardous waste facilities to investigate and clean up any release of hazardous waste into the soil, ground water, surface water and air.
Expanding the Clean Energy Economy for Chemical Companies | Working with Us
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Accelerating Clean Energy Commercialization. A Strategic Partnership Approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adams, Richard; Pless, Jacquelyn; Arent, Douglas J.
Technology development in the clean energy and broader clean tech space has proven to be challenging. Long-standing methods for advancing clean energy technologies from science to commercialization are best known for relatively slow, linear progression through research and development, demonstration, and deployment (RDD&D); and characterized by well-known valleys of death for financing. Investment returns expected by traditional venture capital investors have been difficult to achieve, particularly for hardware-centric innovations, and companies that are subject to project finance risks. Commercialization support from incubators and accelerators has helped address these challenges by offering more support services to start-ups; however, more effort ismore » needed to fulfill the desired clean energy future. The emergence of new strategic investors and partners in recent years has opened up innovative opportunities for clean tech entrepreneurs, and novel commercialization models are emerging that involve new alliances among clean energy companies, RDD&D, support systems, and strategic customers. For instance, Wells Fargo and Company (WFC) and the National Renewable Energy Laboratory (NREL) have launched a new technology incubator that supports faster commercialization through a focus on technology development. The incubator combines strategic financing, technology and technical assistance, strategic customer site validation, and ongoing financial support.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lewis, J.C.; Hochreitner, J.J.
Investigations of potential sources of groundwater contamination conducted by various regulatory agencies and consultants at four industrial sites in Logan Township, New Jersey found groundwater contamination at all four sites and at properties adjoining two of the sites. The four sites directly overlie the Potomac-Raritan-Magothy aquifer system, the Township's sole source of potable water. One site was a waste-oil processing and storage facility. The major source of groundwater contamination at the site is a lagoon containing waste oil. Groundwater within 1,000 ft of the lagoon is contaminated. The second site is used to maintain, dispatch, and clean chemical-transportation tanks. Potentialmore » sources of groundwater contamination at the site include former wastewater lagoons, leaking storage drums, and leaking tank trucks. Groundwater at and immediately north of the property is contaminated. Organic compounds are manufactured at the third site. Potential sources of groundwater contamination at this site include landfilled industrial wastes. Groundwater underlying the property is contaminated, but there is no evidence of offsite groundwater contamination from this source. The fourth site is used to treat and dispose of hazardous wastes. The major source of groundwater contamination at this site is landfilled residue from waste-treatment processes. Groundwater underlying the property is contaminated, but there is no evidence of off-site groundwater contamination from this source.« less
Cleaning at Home and at Work in Relation to Lung Function Decline and Airway Obstruction.
Svanes, Øistein; Bertelsen, Randi J; Lygre, Stein H L; Carsin, Anne E; Antó, Josep M; Forsberg, Bertil; García-García, José M; Gullón, José A; Heinrich, Joachim; Holm, Mathias; Kogevinas, Manolis; Urrutia, Isabel; Leynaert, Bénédicte; Moratalla, Jesús M; Le Moual, Nicole; Lytras, Theodore; Norbäck, Dan; Nowak, Dennis; Olivieri, Mario; Pin, Isabelle; Probst-Hensch, Nicole; Schlünssen, Vivi; Sigsgaard, Torben; Skorge, Trude D; Villani, Simona; Jarvis, Debbie; Zock, Jan P; Svanes, Cecilie
2018-05-01
Cleaning tasks may imply exposure to chemical agents with potential harmful effects to the respiratory system, and increased risk of asthma and respiratory symptoms among professional cleaners and in persons cleaning at home has been reported. Long-term consequences of cleaning agents on respiratory health are, however, not well described. This study aimed to investigate long-term effects of occupational cleaning and cleaning at home on lung function decline and airway obstruction. The European Community Respiratory Health Survey (ECRHS) investigated a multicenter population-based cohort at three time points over 20 years. A total of 6,235 participants with at least one lung function measurement from 22 study centers, who in ECRHS II responded to questionnaire modules concerning cleaning activities between ECRHS I and ECRHS II, were included. The data were analyzed with mixed linear models adjusting for potential confounders. As compared with women not engaged in cleaning (ΔFEV 1 = -18.5 ml/yr), FEV 1 declined more rapidly in women responsible for cleaning at home (-22.1; P = 0.01) and occupational cleaners (-22.4; P = 0.03). The same was found for decline in FVC (ΔFVC = -8.8 ml/yr; -13.1, P = 0.02; and -15.9, P = 0.002; respectively). Both cleaning sprays and other cleaning agents were associated with accelerated FEV 1 decline (-22.0, P = 0.04; and -22.9, P = 0.004; respectively). Cleaning was not significantly associated with lung function decline in men or with FEV 1 /FVC decline or airway obstruction. Women cleaning at home or working as occupational cleaners had accelerated decline in lung function, suggesting that exposures related to cleaning activities may constitute a risk to long-term respiratory health.
Réduction in situ des ions nitrate dans des eaux par les bactéries indigènes
NASA Astrophysics Data System (ADS)
Abdelouas, Abdesselam; Deng, Lijun; Nuttall, Eric; Lutze, Werner; Fritz, Bertrand; Crovisier, Jean-Louis
1999-02-01
We studied the possibility of cleaning groundwater contaminated with nitrate ions using indigenous bacteria. The groundwater occurs in a site located near a former vegetable farm near Albuquerque, New Mexico (USA) and contains up to 500 mg·L -1 of nitrate ion. Batch and column experiments using groundwater and local sediment showed that indigenous bacteria catalyzed the nitrate ions reduction. Sodium acetate was selected as the best carbon source for the in situ application. As expected, the best conditions for denitrification were encountered in situ. Nitrate ions and their byproducts were reduced to nitrogen gas within 5 days.
Wedron Groundwater Site Frequently Asked Questions 2013
Wedron Resource Conservation and Recovery Act (RCRA) Corrective Action program to work with hazardous waste facilities to investigate and clean up any release of hazardous waste into the soil, ground water, surface water and air.
2005-06-01
relative cost -effectiveness of a technology for a given site. DOD has identified a number of contaminants of concern at its facilities, each of...to contain or eliminate hazardous contaminants in groundwater. However, the long cleanup times and high costs of using pump-and- treat technologies...environment. DOD estimates that cleanup of its contaminated sites will cost billions of dollars and may take decades to complete because of the
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, C.; Mutch, S.; Padgett, D.
An investigation was conducted at the Naval Air Facility located in El Centro (NAFEC), to determine the vertical and horizontal extent of hydrocarbon contamination at the facilities fuel farm. The fuel products are the result of tank and pipeline leakage, past tank cleaning, and past disposal of fuel dispensing and filter cleaning practices. Subsurface soil and groundwater data was collected via soil borings, monitoring wells, and CPT probes. Soil, groundwater, and analytical data were integrated using the LYNX geoscience modeling system (GMS). Interactive sessions with the data visualizer helped guide the modeling and identify data gaps. Modeling results indicate amore » continuous surface confining clay layer to a depth of about 12 to 15 ft. Groundwater is confined beneath this clay layer and monitoring wells indicate about 3 to 5 ft of artesian head. Hydrocarbon contamination is concentrated within this clay layer from about 5 to 12 ft below the ground surface. Residual fuel products located in the groundwater are attributed to slow leakage through the confirming clay layer. LYNX was also used to compute volumes of contaminated soil to aid in remediation cost analysis. Preliminary figures indicate about 60,000 yards[sup 3] of contaminated soil. Since the contamination is primarily confined to relatively impermeable clayey soils, site remediation will likely be ex-situ land farming.« less
NASA Astrophysics Data System (ADS)
Fesko, Steve
1996-11-01
Eaton operates a corporate aircraft hanger facility in Battle Creek, Michigan. Tests showed that two underground storage tanks leaked. Investigation confirmed this release discharged several hundred gallons of Jet A kerosene into the soil and groundwater. The oil moved downward approximately 30 feet and spread laterally onto the water table. Test results showed kerosene in the adsorbed, free and dissolved states. Eaton researched and investigated three clean-up options. They included pump and treat, dig and haul and bioremediation. Jet fuel is composed of readily biodegradable hydrocarbon chains. This fact coupled with the depth to groundwater and geologic setting made bioremediation the low cost and most effective alternative. A recovery well was installed at the leading edge of the dissolved contamination. A pump moved water from this well into a nutrient addition system. Nutrients added included nitrogen, phosphorous and potassium. Additionally, air was sparged into the water. The water was discharged into an infiltration gallery installed when the underground storage tanks were removed. Water circulated between the pump and the infiltration basin in a closed loop fashion. This oxygenated, nutrient rich water actively and aggressively treated the soils between the bottom of the gallery and the top of the groundwater and the groundwater. The system began operating in August of 1993 and reduced jet fuel to below detection levels. In August of 1995 The State of Michigan issued a clean closure declaration to the site.
A new design of groundwater sampling device and its application.
Tsai, Yih-jin; Kuo, Ming-ching T
2005-01-01
Compounds in the atmosphere contaminate samples of groundwater. An inexpensive and simple method for collecting groundwater samples is developed to prevent contamination when the background concentration of contaminants is high. This new design of groundwater sampling device involves a glass sampling bottle with a Teflon-lined valve at each end. A cleaned and dried sampling bottle was connected to a low flow-rate peristaltic pump with Teflon tubing and was filled with water. No headspace volume was remained in the sampling bottle. The sample bottle was then packed in a PVC bag to prevent the target component from infiltrating into the water sample through the valves. In this study, groundwater was sampled at six wells using both the conventional method and the improved method. The analysis of trichlorofluoromethane (CFC-11) concentrations at these six wells indicates that all the groundwater samples obtained by the conventional sampling method were contaminated by CFC-11 from the atmosphere. The improved sampling method greatly eliminated the problems of contamination, preservation and quantitative analysis of natural water.
Trends for Electron Beam Accelerator Applications in Industry
NASA Astrophysics Data System (ADS)
Machi, Sueo
2011-02-01
Electron beam (EB) accelerators are major pieces of industrial equipment used for many commercial radiation processing applications. The industrial use of EB accelerators has a history of more than 50 years and is still growing in terms of both its economic scale and new applications. Major applications involve the modification of polymeric materials to create value-added products, such as heat-resistant wires, heat-shrinkable sheets, automobile tires, foamed plastics, battery separators and hydrogel wound dressing. The surface curing of coatings and printing inks is a growing application for low energy electron accelerators, resulting in an environmentally friendly and an energy-saving process. Recently there has been the acceptance of the use of EB accelerators in lieu of the radioactive isotope cobalt-60 as a source for sterilizing disposable medical products. Environmental protection by the use of EB accelerators is a new and important field of application. A commercial plant for the cleaning flue gases from a coal-burning power plant is in operation in Poland, employing high power EB accelerators. In Korea, a commercial plant uses EB to clean waste water from a dye factory.
Regional assessment of groundwater quality for drinking purpose.
Jang, Cheng-Shin
2012-05-01
Owing to limited surface water during a long-term drought, this work attempted to locate clean and safe groundwater in the Choushui River alluvial fan of Taiwan based on drinking-water quality standards. Because aquifers contained several pollutants, multivariate indicator kriging (MVIK) was adopted to integrate the multiple pollutants in groundwater based on drinking- and raw-water quality standards and to explore spatial uncertainty. According to probabilities estimated by MVIK, safe zones were determined under four treatment conditions--no treatment; ammonium-N and iron removal; manganese and arsenic removal; and ammonium-N, iron, manganese, and arsenic removal. The analyzed results reveal that groundwater in the study area is not appropriate for drinking use without any treatments because of high ammonium-N, iron, manganese, and/or arsenic concentrations. After ammonium-N, iron, manganese, and arsenic removed, about 81.9-94.9% of total areas can extract safe groundwater for drinking. The proximal-fan, central mid-fan, southern mid-fan, and northern regions are the excellent locations to pump safe groundwater for drinking after treatment. Deep aquifers of exceeding 200 m depth have wider regions to obtain excellent groundwater than shallow aquifers do.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dorr, Kent A.; Ostrom, Michael J.; Freeman-Pollard, Jhivaun R.
CH2M Hill Plateau Remediation Company (CHPRC) designed, constructed, commissioned, and began operation of the largest groundwater pump and treatment facility in the U.S. Department of Energy's (DOE) nationwide complex. This one-of-a-kind groundwater pump and treatment facility, located at the Hanford Nuclear Reservation Site (Hanford Site) in Washington State, was built in an accelerated manner with American Recovery and Reinvestment Act (ARRA) funds and has attained Leadership in Energy and Environmental Design (LEED) GOLD certification, which makes it the first non-administrative building in the DOE Office of Environmental Management complex to earn such an award. There were many contractual, technical, configurationmore » management, quality, safety, and LEED challenges associated with the design, procurement, construction, and commissioning of this $95 million, 52,000 ft groundwater pump and treatment facility. This paper will present the Project and LEED accomplishments, as well as Lessons Learned by CHPRC when additional ARRA funds were used to accelerate design, procurement, construction, and commissioning of the 200 West Groundwater Pump and Treatment (2W P&T) Facility to meet DOE's mission of treating contaminated groundwater at the Hanford Site with a new facility by June 28, 2012.« less
Self-accelerated development of salt karst during flash floods along the Dead Sea Coast, Israel
NASA Astrophysics Data System (ADS)
Avni, Yoav; Lensky, Nadav; Dente, Elad; Shviro, Maayan; Arav, Reuma; Gavrieli, Ittai; Yechieli, Yoseph; Abelson, Meir; Lutzky, Hallel; Filin, Sagi; Haviv, Itai; Baer, Gidon
2016-01-01
We document and analyze the rapid development of a real-time karst system within the subsurface salt layers of the Ze'elim Fan, Dead Sea, Israel by a multidisciplinary study that combines interferometric synthetic aperture radar and light detection and ranging measurements, sinkhole mapping, time-lapse camera monitoring, groundwater level measurements and chemical and isotopic analyses of surface runoff and groundwater. The >1 m/yr drop of Dead Sea water level and the subsequent change in the adjacent groundwater system since the 1960s resulted in flushing of the coastal aquifer by fresh groundwater, subsurface salt dissolution, gradual land subsidence and formation of sinkholes. Since 2010 this process accelerated dramatically as flash floods at the Ze'elim Fan were drained by newly formed sinkholes. During and immediately after these flood events the dissolution rates of the subsurface salt layer increased dramatically, the overlying ground surface subsided, a large number of sinkholes developed over short time periods (hours to days), and salt-saturated water resurged downstream. Groundwater flow velocities increased by more than 2 orders of magnitudes compared to previously measured velocities along the Dead Sea. The process is self-accelerating as salt dissolution enhances subsidence and sinkhole formation, which in turn increase the ponding areas of flood water and generate additional draining conduits to the subsurface. The rapid terrain response is predominantly due to the highly soluble salt. It is enhanced by the shallow depth of the salt layer, the low competence of the newly exposed unconsolidated overburden and the moderate topographic gradients of the Ze'elim Fan.
Pharmaceuticals as indictors of sewage-influenced groundwater
NASA Astrophysics Data System (ADS)
Müller, Beate; Scheytt, Traugott; Asbrand, Martin; de Casas, Andrea Mross
2012-09-01
A set of human pharmaceuticals enables identification of groundwater that is influenced by sewage and provides information on the time of recharge. As the consumption rates of the investigated pharmaceuticals have changed over time, so too has the composition of the sewage. At the study area, south of Berlin (Germany), irrigation was performed as a method of wastewater clean-up at sewage irrigation farms until the early 1990s. Today, treated wastewater is discharged into the surface-water-stream Nuthegraben. Groundwater and surface-water samples were analyzed for the pharmaceutical substances clofibric acid, bezafibrate, diclofenac, carbamazepine and primidone, the main ions and organic carbon. The pharmaceutical substances were detected at concentrations up to microgram-per-liter level in groundwater and surface-water samples from the Nuthegraben Lowland area and from the former irrigation farms. Concentrations detected in groundwater are generally much lower than in surface water and there is significant variation in the distribution of pharmaceutical concentrations in groundwater. Groundwater influenced by the irrigation of sewage water shows higher primidone and clofibric-acid concentrations. Groundwater influenced by recent discharge of treated sewage water into the surface water shows high carbamazepine concentrations while concentrations of primidone and clofibric acid are low.
Calibrating Treasure Valley Groundwater Model using MODFLOW
NASA Astrophysics Data System (ADS)
Hernandez, J.; Tan, K.
2016-12-01
In Idaho, groundwater plays an especially important role in the state. According to the Idaho Department of Environmental Quality, groundwater supplies 95% of the state's drinking water (2011). The USGS estimates that Idaho withdraws 117 million cubic meters (95,000 acre-feet) per year from groundwater sources for domestic usage which includes drinking water. The same report from the USGS also estimates that Idaho withdraws 5,140 million cubic meters (4,170,000 acre-feet) per year from groundwater sources for irrigation usage. Quantifying and managing that resource and estimating groundwater levels in the future is important for a variety of socio-economic reasons. As the population within the Treasure Valley continues to grow, the demand of clean usable groundwater increases. The objective of this study was to develop and calibrate a groundwater model with the purpose of understanding short- and long-term effects of existing and alternative land use scenarios on groundwater changes. Hydrologic simulations were done using the MODFLOW-2000 model. The model was calibrated for predevelopment period by reproducing and comparing groundwater levels of the years before 1925 using steady state boundary conditions representing no change in the land use. Depending on the reliability of the groundwater source, the economic growth of the area can be constrained or allowed to flourish. Mismanagement of the groundwater source can impact its sustainability, quality and could hamper development by increasing operation and maintenance costs. Proper water management is critical because groundwater is such a limited resource.
Southern California Regional Technology Acceleration Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ochoa, Rosibel; Rasochova, Lada
2014-09-30
UC San Diego and San Diego State University are partnering to address these deficiencies in the renewable energy space in the greater San Diego region, accelerating the movement of clean energy innovation from the university laboratory into the marketplace, building on the proven model of the William J. von Liebig Center’s (vLC’s) Proof of Concept (POC) program and virtualizing the effort to enable a more inclusive environment for energy innovation and expansion of the number of clean energy start-ups and/or technology licenses in greater California.
The U.S. Environmental Protection Agency (EPA) has created the Environmental Technology Verification Program (ETV) to facilitate the deployment of innovative or improved environmental technologies through performance verification and dissemination of information. The goal of the...
Carbon Smackdown: Visualizing Clean Energy (LBNL Summer Lecture Series)
Meza, Juan [LBNL Computational Research Division
2017-12-09
The final Carbon Smackdown match took place Aug. 9, 2010. Juan Meza of the Computational Research Division revealed how scientists use computer visualizations to accelerate climate research and discuss the development of next-generation clean energy technologies such as wind turbines and solar cells.
Industrial Technologies Program - Manufacturing Workforce for a Clean Energy Economy (Green Jobs)
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2010-05-01
Making the transition to a clean energy economy will strengthen our energy security, improve the environment, and create jobs. In 2009, Congress passed a stimulus package to help jump-start all sectors of the U.S. economy and accelerate this transition.
MNA TO ACHIEVE SITE OBJECTIVES: BACK TO BASICS
The U.S. EPA recognizes a three-tiered approach to evaluate site specific data in support of monitored natural attenuation (1) historical groundwater and/or soil chemistry data that demonstrate a clean and meaningful trend of decreasing contaminant mass and/or concentration over ...
Using phytotechnologies to remediate brownfields, landfills, and other urban areas
R.S. Zalesny Jr.; Jill Zalesny
2010-01-01
Urban areas requiring remedial work has prompted the use of phytotechnologies to improve water quality, soil health, and biodiversity, as well as to achieve sustainable social and economic goals. Phytotechnologies directly use plants to clean up contaminated groundwater, soil, and sediment.
NASA Astrophysics Data System (ADS)
Keizer, Floris; Schot, Paul; Wassen, Martin; Kardel, Ignacy; Okruszko, Tomasz
2017-04-01
We studied spatial patterns in inundation water quality, sediment and vegetation distribution in a floodplain fen in Poland to map interacting peatland hydrological processes. Using PCA and K-means cluster analysis, we identified four water types, related to river water inundation, discharge of clean and polluted groundwater, and precipitation and snowmelt dilution. Spatially, these hydrochemical water types are related to known water sources in the floodplain and occupy distinctive zones. River water is found along the river, clean and polluted groundwater at the valley margins and groundwater diluted with precipitation and snowmelt water in the central part of the floodplain. This implies that, despite the floodplain being completely inundated, nutrient input from river flooding occurs only in a relatively narrow zone next to the river. Our findings question the relevance of the edge of inundation, as presented in the Flood Pulse Concept, as delineating the zone of input and turnover of nutrients. Secondly, we studied rich-fen and freshwater vegetation community distributions in relation to the presented inundation water quality types. We successfully determined inundation water quality preference for 14 out of 17 studied rich-fen and freshwater communities in the floodplain. Spatial patterns in preference show vegetation with attributed river water preference to occur close to the river channel, with increasing distance to the river followed by communities with no preference, diluted groundwater preference in the central part, and clean and polluted groundwater preference at the valley margins. In inundation water, nutrients are known to be transported mainly as attached to sediment, besides in dissolved state. This means that in the zone where sediment deposition occurs, nutrient input can be a relevant contribution to the nutrient input of the floodplain. We found a significant decrease in sediment-attached nutrient deposition with distance from the river. Sediment-attached nutrients correlated better to aboveground standing biomass than dissolved nutrients. These findings further reduce the spatial zone where significant nutrient input is influenced by transport from the river, compared to the zone influenced by dissolved nutrients. Our findings indicate the need for a revision of the Flood Pulse Concept for temperate river with multiple water sources, as peatland hydrological processes significantly influence spatial floodplain vegetation distribution.
NASA Astrophysics Data System (ADS)
Fekri, A.; Mohamed, L.
2017-12-01
Egypt has a big water shortage problem because of the high population density and the lack of the surface water resources. So it was necessary to identify additional clean water resources and among all of the other alternative water resources, groundwater should be the most appropriate choice for Egyptians to explore and develop. Saint Katherine area is located in the highest mountainous area of southern Sinai including parallel ridges separated by deep wadis which have been cut along faults and fractures and enlarged through intense precipitation events during the old pluvial periods. Katherina volcanics and the surrounding granitic rocks in Saint Katherine area, which are generally impermeable except through fractures such as faults, joints and shear zones, are recharged with 50 mm annual precipitation. The groundwater recharge find a way through sets of interconnected joints to feed the existing wells in the low-lying fault zones. After the St. Katherine Protectorate was activated in 1996, public awareness of the possible harmful impact of the existing inadequate sewage disposal increased. The groundwater contamination (nitrates and coliform bacteria) in St. Katherine area causes health problems such as diarrhea and skin infections due to the use of well water for household purposes. This study will focus on; monitoring, evaluating and cleaning up the contaminant distribution in St. Katherine groundwater, using a conceptual model for the fault control on the groundwater flow in fractured basement aquifers to understand the possible pathways for the contaminated groundwater (using remote sensing data), and by preparing disinfectant tracers. It is known that Coliform bacteria could be treated by using Sulfanilamide drug, but in this study we will modify the Sulfanilamide compounds which are considered as ligands containing N, O, S donor atoms that could be used to uptake the transition metals, and produce a colored complex. The produced complex will work as a tracer to follow and understand the water path and disinfect water from Coliform bacteria. Moreover, such ligands could be loaded over Natural Polymeric Material or algae to remove nitrates by reducing it into its elemental state of N2.
NASA Astrophysics Data System (ADS)
Nastiti, S. I. W.; Kusnoputranto, H.; Boer, R.; Utomo, S. W.
2018-03-01
The demand for clean water in South Tangerang, Indonesia, is very high. At present, this demand is mostly met by groundwater that is much influenced by climate variability, land cover change, and human activities. The local company on water services (PDAM) provides clean water services for only about 9% of the population. The climate risk assessment conducted by South Tangerang Government in 2016 indicates that several areas are potentially exposed to a high risk of climate change. Survey and in-depth interview with communities and sectoral officers suggest that a risk to clean water supply in this city is increasing. This study aims to assess climate potential risks on clean water supply based on the 2016 study. We adopted the method of that study by modifying some of the vulnerability indicators that can represent clean water access and supply. The results of the study demonstrate that many wards in South Tangerang would be exposed to high climate risks of clean water supply. By 2021, about 54% of wards would be exposed from high to the very very high risk of clean water supply. These results signify the tangible need of adaptation actions, to prevent the worsening impacts of climate on clean water supply.
Attempts for an integrative (ecological) assessment of groundwater ecosystems status
NASA Astrophysics Data System (ADS)
Griebler, Christian; Kellermann, Claudia; Jürgen Hahn, Hans; Stein, Heide; Brielmann, Heike; Berkhoff, Sven; Fuchs, Andreas
2014-05-01
Today the assessment of the ecological status of surface waters is routine and made its way into national and international (e.g. European Water Framework Directive) regulations. For groundwater and aquifers a comparable approach, considering ecological aspects, is still missing. In contrast, groundwater monitoring and management schemes follow exclusively physical-chemical and quantitative criteria. However, groundwater systems are, although persistently neglected, ecosystems harboring diverse communities of microorganisms and invertebrates. Directly linked to the biological components, groundwater systems provide various ecosystem services of societal relevance (natural production of clean drinking water). In the recent past, we developed a first concept of an ecologically sound assessment scheme for groundwater systems. Work included (1) the selection of appropriate biological/ecological criteria, (2) set-up of a groundwater ecosystem typology, (3) deduction of natural biological groundwater background values and definition of reference conditions for selected sites, and (4) a first evaluation model. Groundwater has been analyzed repeatedly of more than 100 wells distributed over five investigation areas spread all over Germany. The investigated sites could be assigned to different natural regions, geological regions, hydrogeological units, and aquifer types. The mismatch of groundwater faunal communities with the established classification schemes led to the proposal of 'stygoregions' for Germany. The presentation introduces a number of microbial and faunistic assessment criteria, which have been tested and natural background values which have been deduced. Finally, a tiered framework for assessing groundwater ecosystem status which allows an easy and fast evaluation is introduced.
De-Trending Techniques: Methods for Cleaning Questionable Shock Data
NASA Technical Reports Server (NTRS)
Grillo, Vincent J.
2010-01-01
Not all zero shifted acceleration data can De-trended using this technique. DC shifts, improper AC coupling, Circuit noise/EMI/EMR, Equivalent RC circuit gain response/Circuit saturation(Slew Rate Limited), fixture grounding and wiring losses can all contribute to bad shock data being recorded. Some data that is zero-shifted or exhibit large instantaneous velocity shifts is inherently bad and a retest is warranted. Clean Acceleration-Time history data can be bad upon examining the Velocity & Displacement profiles. Laser Vibrometers provide a high level of accuracy for pyrotechnic shock testing. Engineering judgment and experience will determine the validity of Shock data.
Is benzene exposure from gasoline carcinogenic?
Jamall, Ijaz S; Willhite, Calvin C
2008-02-01
This article questions the basis for benzene as the carcinogenic surrogate in deriving health risk-based 'clean-up levels' for gasoline-impacted soil and groundwater at leaking underground storage tank properties. The epidemiological evidence suggests that acute myelogenous leukemia (AML) associated with chronic occupational benzene exposure can be best described by sigmoid dose-response relationships. A review of the molecular toxicology and kinetics of benzene points to the existence of threshold mechanisms in the induction of leukemia. The toxicological and epidemiological literature on chronic exposure to unleaded gasoline indicates that the benzene exposures required to induce a measurable carcinogenic response are substantially greater than exposures likely to be encountered from exposure to gasoline at contaminated properties. Thus, assuming that theoretical cancer risks associated with exposure to benzene from gasoline reflect actual health risks associated with such environmental exposures to gasoline and using these theoretical cancer risks and cancer potency factors for benzene to dictate soil and groundwater clean up of gasoline are not scientifically defensible.
Materials compatibility and aging for flux and cleaner combinations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Archuleta, Kim M.; Piatt, Rochelle
2015-01-01
A materials study of high reliability electronics cleaning is presented here. In Phase 1, mixed type substrates underwent a condensed contaminants application to view a worst- case scenario for unremoved flux with cleaning agent residue for parts in a silicone oil filled environment. In Phase 2, fluxes applied to copper coupons and to printed wiring boards underwent gentle cleaning then accelerated aging in air at 65% humidity and 30 O C. Both sets were aged for 4 weeks. Contaminants were no-clean (ORL0), water soluble (ORH1 liquid and ORH0 paste), and rosin (RMA; ROL0) fluxes. Defluxing agents were water, solvents, andmore » engineered aqueous defluxers. In the first phase, coupons had flux applied and heated, then were placed in vials of oil with a small amount of cleaning agent and additional coupons. In the second phase, pairs of copper coupons and PWB were hand soldered by application of each flux, using tin-lead solder in a strip across the coupon or a set of test components on the PWB. One of each pair was cleaned in each cleaning agent, the first with a typical clean, and the second with a brief clean. Ionic contamination residue was measured before accelerated aging. After aging, substrates were removed and a visual record of coupon damage made, from which a subjective rank was applied for comparison between the various flux and defluxer combinations; more corrosion equated to higher rank. The ORH1 water soluble flux resulted in the highest ranking in both phases, the RMA flux the least. For the first phase, in which flux and defluxer remained on coupons, the aqueous defluxers led to worse corrosion. The vapor phase cleaning agents resulted in the highest ranking in the second phase, in which there was no physical cleaning. Further study of cleaning and rinsing parameters will be required.« less
Wovkulich, Karen; Mailloux, Brian J.; Lacko, Allison; Keimowitz, Alison R.; Stute, Martin; Simpson, H. James; Chillrud, Steven N.
2010-01-01
Arsenic is a prevalent contaminant at US Superfund sites where remediation by pump and treat systems is often complicated by slow desorption of As from Fe and Al (hydr)oxides in aquifer solids. Chemical amendments that either compete with As for sorption sites or dissolve Fe and Al (hydr)oxides can increase As mobility and improve pump and treat remediation efficiency. The goal of this work was to determine optimal amendments for improving pump and treat at As contaminated sites such as the Vineland Chemical Co. Superfund site in southern New Jersey. Extraction and column experiments were performed using As contaminated aquifer solids (81 ± 1 mg/kg), site groundwater, and either phosphate (NaH2PO4·H2O) or oxalic acid (C2H2O4·2H2O). In extraction experiments, phosphate mobilized between 11% and 94% of As from the aquifer solids depending on phosphate concentration and extraction time (1 mM-1 M; 1–24 h) and oxalic acid mobilized between 38 and 102% depending on oxalic acid concentration and extraction time (1–400 mM; 1–24 h). In column experiments, phosphate additions induced more As mobilization in the first few pore volumes but oxalic acid was more effective at mobilizing As overall and at lower amendment concentrations. At the end of the laboratory column experiments, 48% of As had been mobilized from the aquifer sediments with 100 mM phosphate and 88% had been mobilized with 10 mM oxalic acid compared with 5% with ambient groundwater alone. Furthermore, simple extrapolations based on pore volumes suggest that chemical treatments could lower the time necessary for clean up at the Vineland site from 600 a with ambient groundwater alone to potentially as little as 4 a with 10 mM oxalic acid. PMID:21076621
USDA-ARS?s Scientific Manuscript database
Excess nutrients from numerous sources (e.g., agricultural and urban runoff, treatment plant discharge, streambank erosion) continue to adversely impact water resources in spite of improved treatment technologies and management practices. In fact, determination of cause(s) of accelerated nutrient e...
NASA Technical Reports Server (NTRS)
Barnett, Donald M.
1995-01-01
Tomco Equipment Company has participated in the dry ice (solid carbon dioxide, CO2) cleaning industry for over ten years as a pioneer in the manufacturer of high density, dry ice cleaning pellet production equipment. For over four years Tomco high density pelletizers have been available to the dry ice cleaning industry. Approximately one year ago Tomco introduced the DI-250, a new dry ice blast unit making Tomco a single source supplier for sublimable media, particle blast, cleaning systems. This new blast unit is an all pneumatic, single discharge hose device. It meters the insertion of 1/8 inch diameter (or smaller), high density, dry ice pellets into a high pressure, propellant gas stream. The dry ice and propellant streams are controlled and mixed from the blast cabinet. From there the mixture is transported to the nozzle where the pellets are accelerated to an appropriate blasting velocity. When directed to impact upon a target area, these dry ice pellets have sufficient energy to effectively remove most surface coatings through dry, abrasive contact. The meta-stable, dry ice pellets used for CO2 cleaning, while labeled 'high density,' are less dense than alternate, abrasive, particle blast media. In addition, after contacting the target surface, they return to their equilibrium condition: a superheated gas state. Most currently used grit blasting media are silicon dioxide based, which possess a sharp tetrahedral molecular structure. Silicon dioxide crystal structures will always produce smaller sharp-edged replicas of the original crystal upon fracture. Larger, softer dry ice pellets do not share the same sharp-edged crystalline structures as their non-sublimable counterparts when broken. In fact, upon contact with the target surface, dry ice pellets will plastically deform and break apart. As such, dry ice cleaning is less harmful to sensitive substrates, workers and the environment than chemical or abrasive cleaning systems. Dry ice cleaning system components include: a dry ice pellet supply, a non-reactive propellant gas source, a pellet and propellant metering device, and a media transport and acceleration hose and nozzle arrangement. Dry ice cleaning system operating parameters include: choice of propellant gas, its pressure and temperature, dry ice mass flow rate, dry ice pellet size and shape, and acceleration nozzle configuration. These parameters may be modified to fit different applications. The growth of the dry ice cleaning industry will depend upon timely data acquisition of the effects that independent changes in these parameters have on cleaning rates, with respect to different surface coating and substrate combinations. With this data, optimization of cleaning rates for particular applications will be possible. The analysis of the applicable range of modulation of these parameters, within system component mechanical constraints, has just begun.
Adaptations of indigenous bacteria to fuel contamination in karst aquifers in south-central Kentucky
Byl, Thomas D.; Metge, David W.; Agymang, Daniel T.; Bradley, Michael W.; Hileman, Gregg; Harvey, Ronald W.
2014-01-01
The karst aquifer systems in southern Kentucky can be dynamic and quick to change. Microorganisms that live in these unpredictable aquifers are constantly faced with environmental changes. Their survival depends upon adaptations to changes in water chemistry, taking advantage of positive stimuli and avoiding negative environmental conditions. The U.S. Geological Survey conducted a study in 2001 to determine the capability of bacteria to adapt in two distinct regions of water quality in a karst aquifer, an area of clean, oxygenated groundwater and an area where the groundwater was oxygen depleted and contaminated by jet fuel. Water samples containing bacteria were collected from one clean well and two jet fuel contaminated wells in a conduit-dominated karst aquifer. Bacterial concentrations, enumerated through direct count, ranged from 500,000 to 2.7 million bacteria per mL in the clean portion of the aquifer, and 200,000 to 3.2 million bacteria per mL in the contaminated portion of the aquifer over a twelve month period. Bacteria from the clean well ranged in size from 0.2 to 2.5 mm, whereas bacteria from one fuel-contaminated well were generally larger, ranging in size from 0.2 to 3.9 mm. Also, bacteria collected from the clean well had a higher density and, consequently, were more inclined to sink than bacteria collected from contaminated wells. Bacteria collected from the clean portion of the karst aquifer were predominantly (,95%) Gram-negative and more likely to have flagella present than bacteria collected from the contaminated wells, which included a substantial fraction (,30%) of Gram-positive varieties. The ability of the bacteria from the clean portion of the karst aquifer to biodegrade benzene and toluene was studied under aerobic and anaerobic conditions in laboratory microcosms. The rate of fuel biodegradation in laboratory studies was approximately 50 times faster under aerobic conditions as compared to anaerobic, sulfur-reducing conditions. The optimum pH for fuel biodegradation ranged from 6 to 7. These findings suggest that bacteria have adapted to water-saturated karst systems with a variety of active and passive transport mechanisms.
Western USA groundwater drilling
NASA Astrophysics Data System (ADS)
Jasechko, S.; Perrone, D.
2016-12-01
Groundwater in the western US supplies 40% of the water used for irrigated agriculture, and provides drinking water to individuals living in rural regions distal to perennial rivers. Unfortunately, current groundwater use is not sustainable in a number of key food producing regions. While substantial attention has been devoted to mapping groundwater depletion rates across the western US, the response of groundwater users via well drilling to changing land uses, water demands, pump and drilling technologies, pollution vulnerabilities, and economic conditions remains unknown. Here we analyze millions of recorded groundwater drilling events in the western US that span years 1850 to 2015. We show that groundwater wells are being drilled deeper in some, but not all, regions where groundwater levels are declining. Groundwater wells are generally deeper in arid and mountainous regions characterized by deep water tables (e.g., unconfined alluvial and fractured bedrock aquifers), and in regions that have productive aquifers with high water quality deep under the ground (e.g., confined sedimentary aquifers). Further, we relate water quality and groundwater drilling depths in 40 major aquifer systems across the western US. We show that there is substantial room for improvement to the existing 2-D continental-scale assessments of domestic well water vulnerability to pollution if one considers the depth that the domestic well is screened in addition to pollutant loading, surficial geology, and vertical groundwater flow rates. These new continental-scale maps can be used to (i) better assess economic, water quality, and water balance limitations to groundwater usage, (ii) steer domestic well drilling into productive strata bearing clean and protected groundwater resources, and (iii) assess groundwater management schemes across the western US.
The demonstration site will be the base dry cleaning facility at Camp Lejeune, North Carolina. Conservative and partitioning tracer tests will be used in conjunction with conventional core and ground-water sampling to characterize the site with respect to DNAPL composition and d...
HYDRAULIC CHARACTERIZATION FOR STEAM ENHANCED REMEDIATION CONDUCTED IN FRACTURED ROCK
Remediation of fractured rock sites contaminated by non-aqueous phase liquids has long been recognized as the most difficult undertaking of any site clean-up. This is primarily the result of the complexity of the fracture framework, which governs the groundwater flow pathways and...
Potential uses of pumped urban groundwater: a case study in Sant Adrià del Besòs (Spain)
NASA Astrophysics Data System (ADS)
Jurado, Anna; Vázquez-Suñé, Enric; Pujades, Estanislao
2017-09-01
Urban groundwater has often been over-exploited for industrial uses. Now, this usage tends to be reduced or the resource abandoned due to pollution and/or changes in land use. The use and the subsequent disuse of groundwater has resulted in rising water tables that damage underground structures (e.g., building basements and underground car parks and tunnels), leading to the need for additional pumping in urban areas. In the case of the underground parking lot of Sant Adrià del Besòs (Barcelona, NE Spain), large amounts of urban groundwater are pumped to avoid seepage problems. Can this pumped groundwater be used for other purposes (e.g., drinking water and urban irrigation) instead of wasting this valuable resource? To answer this question, it was necessary to quantify the groundwater recharge and to assess the evolution of groundwater quality. The limiting factor at this study site is the groundwater quality because ammonium and some metals (iron and manganese) are present at high concentrations. Hence, further treatment would be needed to meet drinking water requirements. The pumped groundwater could also be used for supplementing river flow for ecological benefit and/or for mitigating seawater intrusion problems. Currently, only a small amount of this urban groundwater is used for cleaning public areas and watering public gardens. This situation highlighted the urgent need to manage this resource in a responsible and more efficient manner, especially in moments of high water demand such as drought periods.
NRC evaluates groundwater programs
NASA Astrophysics Data System (ADS)
A recent report by the National Research Council (NRC) noted that about half the people of the United States depend on wells for their drinking water, but recent tests reveal widespread contamination.Responsibility for monitoring and protecting groundwater supplies lies largely with state governments. Federal funding of model projects under the Clean Water Act expired in 1983. However, the U.S. Environmental Protection Agency (EPA) has asked the NRC to identify and evaluate ten state and local groundwater protection programs and to recommend features that may be applied in other areas. A committee, organized by the Water Science and Technology Board and chaired by Jerome B. Gilbert, general manager of the East Bay Municipal Utility District of Oakland, Calif., has undertaken the study. The report is expected to be completed in March 1986.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zielke, Jason
The DoE Innovation Ecosystem Initiative was a gamechanger for Clean Energy Trust. The grant accelerated our development from a concept to a real company in 2010, seeding us with the capital to begin our mission to “accelerate the growth of clean energy businesses in the Midwest”. Now three years later, we have scores and scores of partners which fund us through sponsorship donations to our programs, and we have played a key role in launching several new companies, and helping them acquire funding and reach their milestones. In three years we have grown from two people to nine, now withmore » an annual budget of over $3M. We started with the following simple plan (verbatim from our original submission): “The short-term objective of ICE is to fortify and enhance the platform for collaboration necessary to create a robust ecosystem for clean energy innovation. This includes launching a number of initiatives designed to source, evaluate, and launch new clean energy businesses derived from university research.« less
NASA Technical Reports Server (NTRS)
Shannon, R. L.; Gillette, R. B.
1974-01-01
The technique which utilizes exposure to a plasma to remove contaminants from a surface was incorporated into a laboratory model which demonstrates active cleaning by both plasma cleaning and ion sputtering modes of operation. The development phase is reported and includes discussion of the plasma tube configuration, device design, and performance tests. A general description of the active cleaning device is provided which includes information on the main power/plasma discharge sensors, and the power, gas supply, and ion accelerator systems. Development of the active cleaning species at high vacuum conditions is described and results indicate that plasma cleaning occurs in the region of a visible plume which extends from the end of the plasma tube. Recommendations are made for research to determine the plasma cleaning mechanism and the plasma species responsible for the cleaning, as well limitations on the type of contaminants that can be removed.
Site Environmental Report for 2015
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pauer, Ron O.; Baskin, David A.; Borglin, Ned K.
The annual Site Environmental Report documents Lawrence Berkeley National Laboratory’s performance in reducing its environmental impacts, progress toward cleaning up groundwater contamination, and compliance with applicable Department of Energy, federal, state, and local environmental regulations. The report is required by DOE Order 231.1B, Environment, Safety, and Health Reporting.
40 CFR 149.3 - Critical Aquifer Protection Areas.
Code of Federal Regulations, 2010 CFR
2010-07-01
... ground-water quality protection plan was approved, under section 208 of the Clean Water Act, prior to that date; or (b) All or part of a major recharge area of a sole or principal source aquifer....3 Section 149.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS...
40 CFR 149.3 - Critical Aquifer Protection Areas.
Code of Federal Regulations, 2011 CFR
2011-07-01
... ground-water quality protection plan was approved, under section 208 of the Clean Water Act, prior to that date; or (b) All or part of a major recharge area of a sole or principal source aquifer....3 Section 149.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS...
The Weston/IEG UVB technology is an in situ groundwater remediation technology that combines air-lift pumping and air stripping to clean aquifers contaminated with volatile organic compounds. A UVB system consists of a single well with two hydraulically separated screened interva...
ERIC Educational Resources Information Center
Evans, Alexandra L.; Messersmith, Reid E.; Green, David B.; Fritsch, Joseph M.
2011-01-01
We present an integrative laboratory investigation incorporating skills from inorganic chemistry, analytical instrumentation, and physical chemistry applied to a laboratory-scale model of the environmental problem of chlorinated ethylenes in groundwater. Perchloroethylene (C[subscript 2]Cl[subscript 4], PCE) a common dry cleaning solvent,…
Receiving and use of streams of monodisperse ice granules for cleaning and deactivation of surfaces
NASA Astrophysics Data System (ADS)
Boukharov, A.; Balashov, A.; Timohin, A.; Ivanov, A.; Holin, B.
2017-11-01
The most generally useful methods for cleaning and processing of surfaces are the sand-jets and shot blasting jets. Installations of this kind are used for cleaning of corrosion surfaces, the oil-dirt deposits, paint coatings. However the use of these installations follows to high investment and operational expenditure, larger risk of operators disease, the negative affect for a environment. These problems can be solved with the use of new cleaning method through application of mono-disperse (identical by the size and the form) ice granules of 300 - 1000 microns, accelerated by air stream in the nozzle device to the speed of 10 - 100 m/s. In view of the extreme complexity of the receiving such particles by means of cooling and the subsequent freezing of water drops are necessary additional experimental researches. For study of thermal processes of receiving mono-disperse ice granules the experimental installation was created and experiments on deactivation and cleaning of surfaces with pollution of various types are made. Experiments showed that by means of a stream of the accelerated ice granules it is rather successfully possible to delete oil-dirt deposits, outdated paint coats and rust. Besides, efficient deactivation of radioactive surfaces is possible. The coefficient deactivation of γ activity is highest.
NASA Astrophysics Data System (ADS)
Yuval; Rimon, Y.; Graber, E. R.; Furman, A.
2013-07-01
A large fraction of the fresh water available for human use is stored in groundwater aquifers. Since human activities such as mining, agriculture, industry and urbanization often result in incursion of various pollutants to groundwater, routine monitoring of water quality is an indispensable component of judicious aquifer management. Unfortunately, groundwater pollution monitoring is expensive and usually cannot cover an aquifer with the spatial resolution necessary for making adequate management decisions. Interpolation of monitoring data between points is thus an important tool for supplementing measured data. However, interpolating routine groundwater pollution data poses a special problem due to the nature of the observations. The data from a producing aquifer usually includes many zero pollution concentration values from the clean parts of the aquifer but may span a wide range (up to a few orders of magnitude) of values in the polluted areas. This manuscript presents a methodology that can cope with such datasets and use them to produce maps that present the pollution plumes but also delineates the clean areas that are fit for production. A method for assessing the quality of mapping in a way which is suitable to the data's dynamic range of values is also presented. Local variant of inverse distance weighting is employed to interpolate the data. Inclusion zones around the interpolation points ensure that only relevant observations contribute to each interpolated concentration. Using inclusion zones improves the accuracy of the mapping but results in interpolation grid points which are not assigned a value. That inherent trade-off between the interpolation accuracy and coverage is demonstrated using both circular and elliptical inclusion zones. A leave-one-out cross testing is used to assess and compare the performance of the interpolations. The methodology is demonstrated using groundwater pollution monitoring data from the Coastal aquifer along the Israeli shoreline.
Yuval, Yuval; Rimon, Yaara; Graber, Ellen R; Furman, Alex
2014-08-01
A large fraction of the fresh water available for human use is stored in groundwater aquifers. Since human activities such as mining, agriculture, industry and urbanisation often result in incursion of various pollutants to groundwater, routine monitoring of water quality is an indispensable component of judicious aquifer management. Unfortunately, groundwater pollution monitoring is expensive and usually cannot cover an aquifer with the spatial resolution necessary for making adequate management decisions. Interpolation of monitoring data is thus an important tool for supplementing monitoring observations. However, interpolating routine groundwater pollution data poses a special problem due to the nature of the observations. The data from a producing aquifer usually includes many zero pollution concentration values from the clean parts of the aquifer but may span a wide range of values (up to a few orders of magnitude) in the polluted areas. This manuscript presents a methodology that can cope with such datasets and use them to produce maps that present the pollution plumes but also delineates the clean areas that are fit for production. A method for assessing the quality of mapping in a way which is suitable to the data's dynamic range of values is also presented. A local variant of inverse distance weighting is employed to interpolate the data. Inclusion zones around the interpolation points ensure that only relevant observations contribute to each interpolated concentration. Using inclusion zones improves the accuracy of the mapping but results in interpolation grid points which are not assigned a value. The inherent trade-off between the interpolation accuracy and coverage is demonstrated using both circular and elliptical inclusion zones. A leave-one-out cross testing is used to assess and compare the performance of the interpolations. The methodology is demonstrated using groundwater pollution monitoring data from the coastal aquifer along the Israeli shoreline. The implications for aquifer management are discussed.
NASA Astrophysics Data System (ADS)
Frederiks, R.; Lowry, C.; Mutiibwa, R.; Moisy, S.; Thapa, L.; Oriba, J.
2017-12-01
In the past two years, Uganda has witnessed an influx of nearly one million refugees who have settled in the sparsely populated northwestern region of the country. This rapid population growth has created high demand for clean water resources. Water supply has been unable to keep pace with demand because the fractured rock aquifers underlying the region often produce low yielding wells. To facilitate management of groundwater resources, it is necessary to quantify the spatial distribution of groundwater. In fractured rock aquifers, there is significant spatial variability in water storage because fractures must be both connected and abundant for water to be extracted in usable quantities. Two conceptual models were evaluated to determine the groundwater storage mechanism in the fractured crystalline bedrock aquifers of northwestern Uganda where by permeability is controlled by faulting, which opens up fractures in the bedrock, or weathering, which occurs when water dissolves components of rock. In order to test these two conceptual models, geologic well logs and available hydrologic data were collected and evaluated using geostatistical and numerical groundwater models. The geostatistical analysis focused on identifying spatially distributed patterns of high and low water yield. The conceptual models were evaluated numerically using four inverse groundwater MODFLOW models based on head and estimated flux targets. The models were based on: (1) the mapped bedrock units using an equivalent porous media approach (2) bedrock units with the addition of known fault zones (3) bedrock units with predicted units of deep weathering based on surface slopes, and (4) bedrock units with discrete faults and simulated weathered zones. Predicting permeable zones is vital for water well drilling in much of East Africa and South America where there is an abundance of both fractured rock and tectonic activity. Given that the population of these developing regions is growing, the demand for sufficient clean water is likely to increase significantly in the next few decades. Thus, it is necessary to improve our ability to predict locations of permeable zones in fractured rock aquifers.
Revealed social preference for potable groundwater: An Eastern Iowa case study
NASA Astrophysics Data System (ADS)
Raunikar, R. P.; Bernknopf, R. L.; Forney, W.; Mishra, S.
2011-12-01
The spatially explicit land use and land cover information provided by Landsat moderate-resolution land imagery (MRLI) is needed to more efficiently balance the production of goods and services over landscapes. For example, economic trade-offs are needed to provide both clean groundwater resources and other non-environmental goods and services produced by activities that affect the vadose zone and thus contribute to contamination of groundwater. These trade-off choices are made by numerous economic agents and are constrained by many social institutions including governmental regulations at many levels, contractual obligations and traditions. In effect, on a social level, society acts as if it values groundwater by foregoing other goods to protect these resources. The result of the protection afforded to groundwater resources is observable by measuring contamination in well samples. This observed level of groundwater contamination risk is the revealed preference of society as a whole for clean groundwater. We observed the risk of groundwater contamination in a sampling of well data from our study area (35 counties of Eastern Iowa.) We used a proportional hazard model to quantify the nitrate contamination survival implied by the panel of 19,873 well data, where remaining below a 10 mg/ml maximum contamination level (MCL) is defined as survival. We tested the data for evidence that the levels of protection provided to these resources is correlated with aquifer and vadose zone characteristics and geographic location and whether it changed over time and with economic and other conditions. We demonstrate the use of a nitrate conditioned hazard function for projecting the survival of wells based on nitrate exposure information over the 1940 to 2010 time period. We discuss results of simulations of the survival process that demonstrate the economic significance of this approach. We find that aquifer survival has been significantly improving over time. The principle of revealed preference is the concept from economic consumer theory meaning that the observed consumption bundle chosen (e.g. the amounts of crop production, groundwater risk and everything else) is preferred to any other bundle possible (e.g. the bundle including more crop production and the concomitant increase in groundwater risk) given the constraints the consumer faces. This concept was initially applied at the level of an individual consumer, but it also applies by the same logic at the social level of analysis. Using the spatially explicit information provided by Landsat MRLI about land use on the surfaces recharging the aquifers, more efficient regulation can be devised to allow more production on the surface while protecting aquifers to the degree implied by this revealed preference analysis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Copland, John Robin; Cochran, John Russell
2013-07-01
The Radiation Protection Center of the Iraqi Ministry of Environment is developing a groundwater monitoring program (GMP) for the Al-Tuwaitha Nuclear Research Center located near Baghdad, Iraq. The Al-Tuwaitha Nuclear Research Center was established in about 1960 and is currently being cleaned-up and decommissioned by Iraqs Ministry of Science and Technology. This Groundwater Monitoring Program Plan (GMPP) and Conceptual Site Model (CSM) support the Radiation Protection Center by providing: A CSM describing the hydrogeologic regime and contaminant issues, recommendations for future groundwater characterization activities, and descriptions of the organizational elements of a groundwater monitoring program. The Conceptual Site Model identifiesmore » a number of potential sources of groundwater contamination at Al-Tuwaitha. The model also identifies two water-bearing zones (a shallow groundwater zone and a regional aquifer). The depth to the shallow groundwater zone varies from approximately 7 to 10 meters (m) across the facility. The shallow groundwater zone is composed of a layer of silty sand and fine sand that does not extend laterally across the entire facility. An approximately 4-m thick layer of clay underlies the shallow groundwater zone. The depth to the regional aquifer varies from approximately 14 to 17 m across the facility. The regional aquifer is composed of interfingering layers of silty sand, fine-grained sand, and medium-grained sand. Based on the limited analyses described in this report, there is no severe contamination of the groundwater at Al-Tuwaitha with radioactive constituents. However, significant data gaps exist and this plan recommends the installation of additional groundwater monitoring wells and conducting additional types of radiological and chemical analyses.« less
McDowell, Thomas W; Welcome, Daniel E; Warren, Christopher; Xu, Xueyan S; Dong, Ren G
2013-01-01
Motorized vibrating manure forks were used in beach-cleaning operations following the massive Deepwater Horizon oil spill in the Gulf of Mexico during the summer of 2010. The objectives of this study were to characterize the vibration emissions of these motorized forks and to provide a first approximation of hand-transmitted vibration exposures to workers using these forks for beach cleaning. Eight operators were recruited to operate the motorized forks during this laboratory study. Four fork configurations were used in the study; two motor speeds and two fork basket options were evaluated. Accelerations were measured near each hand as the operators completed the simulated beach-cleaning task. The dominant vibration frequency for these tools was identified to be around 20 Hz. Because acceleration was found to increase with motor speed, workers should consider operating these tools with just enough speed to get the job done. These forks exhibited considerable acceleration magnitudes when unloaded. The study results suggest that the motor should not be operated with the fork in the unloaded state. Anti-vibration gloves are not effective at attenuating the vibration frequencies produced by these forks, and they may even amplify the transmitted vibration and increase hand/arm fatigue. While regular work gloves are suitable, vibration-reducing gloves may not be appropriate for use with these tools. These considerations may also be generally applicable for the use of motorized forks in other workplace environments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ferriter, J.P.
The paper begins by describing the role of the International Energy Agency, the importance of coal, what the IEA is doing in the area of clean coal technology, and the role of the IEA Coal Industry Advisory Board. The paper then discusses which coal technologies will be chosen, what the problem areas are, and what can be done to accelerate the take-up of clean coal technologies.
Organohalide respiration and bioremediation: harnessing biogeochemical cycles (Invited)
NASA Astrophysics Data System (ADS)
Edwards, E.; Hug, L.; Perez de Mora, A.
2013-12-01
Groundwater contamination is a serious threat to global health and prosperity. Chlorinated solvents are widely used as industrial degreasers, dry-cleaning agents and precursors in chemical synthesis, and therefore are common groundwater contaminants. Owing to their toxicity, even small spills render groundwater unsuitable for use, and cleanup is typically a costly and long-term undertaking. Dehalococcoides, Dehalobacter, Dehalogenimonas and other unusual microbes have been discovered that can dechlorinate many groundwater contaminants, in particular, the common solvents tetrachloroethene and trichloroethene to the benign product ethene. Remarkably, these organisms obtain energy for growth from dechlorination in a process termed organohalide respiration. The use of biostimulation and bioaugmentation is growing, even at sites with complex hydrogeology and high concentrations of contaminants. Molecular understanding of the unusual metabolism of these organisms is helping to design successful remediation strategies. Four aspects will be emphasized: 1) the nature of the remarkable enzymes that catalyze dechlorination reactions, 2) the role of the non-dechlorinating microbes in providing essential nutrients to dechlorinating organisms, 3) the effects of mixtures of contaminants and 4) the origins of organohalide respiration. Morevoer, the hunt is on to further explore nature's diversity to discover other unusual or novel microbes capable of detoxifying a broader range of contaminants. New molecular biology and genomic tools are helping us understand how these microbes make a living, and how we can take advantage of their abilities to clean up the environment. In this presentation I will review some of the current trends in bioremediation with particular focus on how molecular tools are helping with remediation design, scope and troubleshooting. I will draw from a number of examples from my own laboratory and elsewhere.
Glow discharge cleaning of vacuum switch tubes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hayashi, T.; Toya, H.
1991-10-01
This paper reports that glow discharge cleaning has ben advancing as a means of degassing vacuum chambers constructed for a large accelerator or for nuclear fusion research. To clean the whole surface of parts inside a vacuum switch tube (VST), a new technique is tried which generates glow discharge between the inner electrodes and copper grid surrounding it. Photographic observation reveals that the glow discharge spreads out and cleans the whole surface inside the VST. A breakdown test between the inner electrodes shows the effect of the cleaning with this technique. Higher breakdown voltage between the inner electrodes is attainedmore » by performing this glow discharge cleaning in argon rather than hydrogen gas. The difference of the cleaning effect seems to be attributed to that of the energy transfer from ion species to the absorbed molecules and microprotrusions on the surfaces.« less
MIT Clean Energy Prize: Final Technical Report May 12, 2010 - May 11, 2011
DOE Office of Scientific and Technical Information (OSTI.GOV)
Snyder, Chris; Campbell, Georgina; Salony, Jason
2011-08-09
The MIT Clean Energy Prize (MIT CEP) is a venture creation and innovation competition to encourage innovation in the energy space, specifically with regard to clean energy. The Competition invited student teams from any US university to submit student-led ventures that demonstrate a high potential of successfully making clean energy more affordable, with a positive impact on the environment. By focusing on student ventures, the MIT CEP aims to educate the next generation of clean energy entrepreneurs. Teams receive valuable mentoring and hard deadlines that complement the cash prize to accelerate development of ventures. The competition is a year-long educationalmore » process that culminates in the selection of five category finalists and a Grand Prize winner and the distribution of cash prizes to each of those teams. Each entry was submitted in one of five clean energy categories: Renewables, Clean Non-Renewables, Energy Efficiency, Transportation, and Deployment.« less
Active cleaning technique device
NASA Technical Reports Server (NTRS)
Shannon, R. L.; Gillette, R. B.
1973-01-01
The objective of this program was to develop a laboratory demonstration model of an active cleaning technique (ACT) device. The principle of this device is based primarily on the technique for removing contaminants from optical surfaces. This active cleaning technique involves exposing contaminated surfaces to a plasma containing atomic oxygen or combinations of other reactive gases. The ACT device laboratory demonstration model incorporates, in addition to plasma cleaning, the means to operate the device as an ion source for sputtering experiments. The overall ACT device includes a plasma generation tube, an ion accelerator, a gas supply system, a RF power supply and a high voltage dc power supply.
THE TRANSPORT AND FATE OF ETHANOL AND BTEX IN GROUNDWATER CONTAMINATED BY GASOHOL. (R821114)
Ethanol is used a component in all gasoline in Brazil, and its use could increase significantly in the U.S. to meet the requirements of the Clean Air Act Amendments. Recent problems with ground water contamination by methyl tert-butyl ether (MTBE) have made policymakers more c...
UNDERGROUND STORAGE TANK SITE CLOSURE USING ACTIVE INTERVENTION FOR SITE CLEANUP
The Clean Air Act Amendments of 1990 mandate seasonal or year-round use of oxygenated compounds in gasoline in certain areas of the country. Methyl t-butyl ether (MtBE) has been the most commonly used oxygenate. However, the use of MtBE has created a significant risk to groundwat...
Sorption of Groundwater Dissolved Organic Carbon onto Minerals
NASA Astrophysics Data System (ADS)
Rutlidge, H.; Oudone, P.; McDonough, L.; Meredith, K.; Andersen, M. S.; O'Carrol, D. M.; Baker, A.
2017-12-01
Our understanding of groundwater organic matter (OM) as a carbon source or sink in the environmental carbon cycle is limited. The dynamics of groundwater OM is mainly governed by biological processing and its sorption to minerals. In saturated groundwaters, dissolved OM (DOM) represents one part of the groundwater organic carbon pool. Without consideration of the DOM sorption, it is not possible to quantify governing groundwater OM processes. This research explores the rate and extent of DOM sorption on different minerals. Groundwater DOM samples, and International Humic Substances Society (IHSS) standard solutions, were analysed. Each was mixed with a range of masses of iron coated quartz, clean quartz, and calcium carbonate, and shaken for 2 hours to reach equilibrium before being filtered through 0.2 μm for total dissolved organic carbon (DOC) and composition analysis by size-exclusion chromatography-organic carbon detection (LC-OCD). Sorption isotherms were constructed and groundwater DOM sorption were compared to the sorption of IHSS standards. Initial results suggest that for the IHSS standards, the operationally-defined humic substances fraction had the strongest sorption compared to the other LC-OCD fractions and total DOC. Some samples exhibited a small increase in the low molecular weight neutral (LMW-N) aqueous concentration with increasing humic substances sorption. This gradual increase observed could be the result of humic substances desorbing or their breakdown during the experiment. Further results comparing these IHSS standards with groundwater samples will be presented. In conjunction with complementary studies, these results can help provide more accurate prediction of whether groundwater OM is a carbon source or sink, which will enable the management of the groundwater resources as part of the carbon economy.
Simplified Method for Groundwater Treatment Using Dilution and Ceramic Filter
NASA Astrophysics Data System (ADS)
Musa, S.; Ariff, N. A.; Kadir, M. N. Abdul; Denan, F.
2016-07-01
Groundwater is one of the natural resources that is not susceptible to pollutants. However, increasing activities of municipal, industrial, agricultural or extreme land use activities have resulted in groundwater contamination as occured at the Research Centre for Soft Soil Malaysia (RECESS), Universiti Tun Hussein Onn Malaysia (UTHM). Thus, aims of this study is to treat groundwater by using rainwater and simple ceramic filter as a treatment agent. The treatment uses rain water dilution, ceramic filters and combined method of dilute and filtering as an alternate treatment which are simple and more practical compared to modern or chemical methods. The water went through dilution treatment processes able to get rid of 57% reduction compared to initial condition. Meanwhile, the water that passes through the filtering process successfully get rid of as much as 86% groundwater parameters where only chloride does not pass the standard. Favorable results for the combination methods of dilution and filtration methods that can succesfully eliminate 100% parameters that donot pass the standards of the Ministry of Health and the Interim National Drinking Water Quality Standard such as those found in groundwater in RECESS, UTHM especially sulfate and chloride. As a result, it allows the raw water that will use clean drinking water and safe. It also proves that the method used in this study is very effective in improving the quality of groundwater.
Distributed Memory Parallel Computing with SEAWAT
NASA Astrophysics Data System (ADS)
Verkaik, J.; Huizer, S.; van Engelen, J.; Oude Essink, G.; Ram, R.; Vuik, K.
2017-12-01
Fresh groundwater reserves in coastal aquifers are threatened by sea-level rise, extreme weather conditions, increasing urbanization and associated groundwater extraction rates. To counteract these threats, accurate high-resolution numerical models are required to optimize the management of these precious reserves. The major model drawbacks are long run times and large memory requirements, limiting the predictive power of these models. Distributed memory parallel computing is an efficient technique for reducing run times and memory requirements, where the problem is divided over multiple processor cores. A new Parallel Krylov Solver (PKS) for SEAWAT is presented. PKS has recently been applied to MODFLOW and includes Conjugate Gradient (CG) and Biconjugate Gradient Stabilized (BiCGSTAB) linear accelerators. Both accelerators are preconditioned by an overlapping additive Schwarz preconditioner in a way that: a) subdomains are partitioned using Recursive Coordinate Bisection (RCB) load balancing, b) each subdomain uses local memory only and communicates with other subdomains by Message Passing Interface (MPI) within the linear accelerator, c) it is fully integrated in SEAWAT. Within SEAWAT, the PKS-CG solver replaces the Preconditioned Conjugate Gradient (PCG) solver for solving the variable-density groundwater flow equation and the PKS-BiCGSTAB solver replaces the Generalized Conjugate Gradient (GCG) solver for solving the advection-diffusion equation. PKS supports the third-order Total Variation Diminishing (TVD) scheme for computing advection. Benchmarks were performed on the Dutch national supercomputer (https://userinfo.surfsara.nl/systems/cartesius) using up to 128 cores, for a synthetic 3D Henry model (100 million cells) and the real-life Sand Engine model ( 10 million cells). The Sand Engine model was used to investigate the potential effect of the long-term morphological evolution of a large sand replenishment and climate change on fresh groundwater resources. Speed-ups up to 40 were obtained with the new PKS solver.
Supersonic Gas-Liquid Cleaning System
NASA Technical Reports Server (NTRS)
Kinney, Frank
1996-01-01
The Supersonic Gas-Liquid Cleaning System Research Project consisted mainly of a feasibility study, including theoretical and engineering analysis, of a proof-of-concept prototype of this particular cleaning system developed by NASA-KSC. The cleaning system utilizes gas-liquid supersonic nozzles to generate high impingement velocities at the surface of the device to be cleaned. The cleaning fluid being accelerated to these high velocities may consist of any solvent or liquid, including water. Compressed air or any inert gas is used to provide the conveying medium for the liquid, as well as substantially reduce the total amount of liquid needed to perform adequate surface cleaning and cleanliness verification. This type of aqueous cleaning system is considered to be an excellent way of conducting cleaning and cleanliness verification operations as replacements for the use of CFC 113 which must be discontinued by 1995. To utilize this particular cleaning system in various cleaning applications for both the Space Program and the commercial market, it is essential that the cleaning system, especially the supersonic nozzle, be characterized for such applications. This characterization consisted of performing theoretical and engineering analysis, identifying desirable modifications/extensions to the basic concept, evaluating effects of variations in operating parameters, and optimizing hardware design for specific applications.
Yan, Wudan
2017-01-01
Water on Earth-in our oceans, rivers, lakes, and wetlands-might seem plentiful, but water that is clean and safe enough to drink actually isn't so abundant. Nearly one in ten people still lacks access to safe water worldwide, according to the World Health Organization. In some of the world's most remote and impoverished communities, people live with no taps, showers, flushing toilets, or nearby springs, making it difficult to keep water supplies safe from bacteria, chemicals, and particulates. Moreover, access to clean drinking water isn't just a problem in the developing world; groundwater in developed countries is typically used far more quickly than it is being replenished. As the world population rises, growing numbers of thirsty people could exacerbate already-scant resources.
Cleaning techniques for intense ion beam sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Menge, P.R.; Cuneo, M.E.; Bailey, J.E.
Generation of high power lithium ion beams on the SABRE (1TW) and PBFA-X (20 TW) accelerators have been limited by the parallel acceleration of contaminant ions. during the beam pulse lithium is replaced by protons and carbon ions. This replacement is accompanied by rapid impedance decay of the diode. The contaminant hydrogen and carbon is believed to originate from impurity molecules on the surface and in the bulk of the lithium ion source and its substrate material. Cleaning techniques designed to remove hydrocarbons from the ion source have been employed with some success in test stand experiments and on SABRE.more » The test stand experiments have shown that a lithium fluoride (LiF) ion source film can accrue dozens of hydrocarbon monolayers on its surface while sitting in vacuum. Application of 13.5 MHz RF discharge cleaning with 90% Ar/10% O{sub 2} can significantly reduce the surface hydrocarbon layers on the LiF film. On SABRE, combinations of RF discharge cleaning, anode heating, layering gold between the source film (LiF) and its substrate, and cryogenic cathode cooling produced an increase by a factor of 1.5--2 in the quantity of high energy lithium in the ion beam. A corresponding decrease in protons and carbon ions was also observed. Cleaning experiments on PBFA-X are underway. New designs of contamination resistant films and Li ion sources are currently being investigated.« less
NASA Astrophysics Data System (ADS)
Sutton, Patrick T.; Ginn, Timothy R.
2014-12-01
A sustainable in-well vapor stripping system is designed as a cost-effective alternative for remediation of shallow chlorinated solvent groundwater plumes. A solar-powered air compressor is used to inject air bubbles into a monitoring well to strip volatile organic compounds from a liquid to vapor phase while simultaneously inducing groundwater circulation around the well screen. An analytical model of the remediation process is developed to estimate contaminant mass flow and removal rates. The model was calibrated based on a one-day pilot study conducted in an existing monitoring well at a former dry cleaning site. According to the model, induced groundwater circulation at the study site increased the contaminant mass flow rate into the well by approximately two orders of magnitude relative to ambient conditions. Modeled estimates for 5 h of pulsed air injection per day at the pilot study site indicated that the average effluent concentrations of dissolved tetrachloroethylene and trichloroethylene can be reduced by over 90% relative to the ambient concentrations. The results indicate that the system could be used cost-effectively as either a single- or multi-well point technology to substantially reduce the mass of dissolved chlorinated solvents in groundwater.
Numerical simulations of a proposed hollow electron beam collimator for the LHC upgrade at CERN.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Previtali, V.; Stancari, G.; Valishev, A.
2013-07-12
In the last years the LHC collimation system has been performing over the expectations, providing the machine with a nearly perfect e cient cleaning system[1]. Nonetheless, when trying to push the existing accelerators to - and over - their design limits, all the accelerator components are required to boost their performances. In particular, in view of the high luminosity frontier for the LHC, the increased intensity would ask for a more e cient cleaning system. In this framework innovative collimation solutions are under evaluation[2]: one option is the usage of an hollow electron lens for beam halo cleaning. This workmore » intends to study the applicability of an the hollow electron lens for the LHC collimation, by evaluating the case of the existing Tevatron e-lens applied to the nominal LHC 7 TeV beam. New e-lens operation modes are here proposed to standard enhance the electron lens halo removal e ect.« less
Thiros, Susan A.; Bender, David A.; Mueller, David K.; Rose, Donna L.; Olsen, Lisa D.; Martin, Jeffrey D.; Bernard, Bruce; Zogorski, John S.
2011-01-01
The Field Contamination Study (FCS) was designed to determine the field processes that tend to result in clean field blanks and to identify potential sources of contamination to blanks collected in the field from selected volatile organic compounds (VOCs) and wastewater-indicator compounds (WICs). The VOCs and WICs analyzed in the FCS were detected in blanks collected by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program during 1996–2008 and 2002–08, respectively. To minimize the number of variables, the study required ordering of supplies just before sampling, storage of supplies and equipment in clean areas, and use of adequate amounts of purge-and-trap volatile-grade methanol and volatile pesticide-grade blank water (VPBW) to clean sampling equipment and to collect field blanks.Blanks and groundwater samples were collected during 2008–09 at 16 sites, which were a mix of water-supply and monitoring wells, located in 9 States. Five different sample types were collected for the FCS at each site: (1) a source-solution blank collected at the USGS National Water Quality Laboratory (NWQL) using laboratory-purged VPBW, (2) source-solution blanks collected in the field using laboratory-purged VPBW, (3) source-solution blanks collected in the field using field-purged VPBW, (4) a field blank collected using field-purged VPBW, and (5) a groundwater sample collected from a well. The source-solution blank and field-blank analyses were used to identify, quantify, and document extrinsic contamination and to help determine the sources and causes of data-quality problems that can affect groundwater samples.Concentrations of compounds detected in FCS analyses were quantified and results were stored in the USGS National Water Information System database after meeting rigorous identification and quantification criteria. The study also utilized information provided by laboratory analysts about evidence indicating the presence of selected compounds, using less rigorous identification criteria than is required for reporting data to the National Water Information System database. For the FCS, these data are considered adequate to indicate "evidence of presence," and were used only for diagnostic purposes. Evidence of VOCs and WICs at low concentrations near or less than the long-term method detection level can indicate a contamination problem that could affect future datasets if method detection levels were ever to be lowered.
Filtration of water-sediment samples for the determination of organic compounds
Sandstrom, Mark W.
1995-01-01
This report describes the equipment and procedures used for on-site filtration of surface-water and ground-water samples for determination of organic compounds. Glass-fiber filters and a positive displacement pumping system are suitable for processing most samples for organic analyses. An optional system that uses disposable in-line membrane filters is suitable for a specific gas chromatography/mass spectrometry, selected-ion monitoring analytical method for determination of organonitrogen herbicides. General procedures to minimize contamination of the samples include preparing a clean workspace at the site, selecting appropriate sample-collection materials, and cleaning of the equipment with detergent, tap water, and methanol.
Phuntsho, Sherub; Lotfi, Fezeh; Hong, Seungkwan; Shaffer, Devin L; Elimelech, Menachem; Shon, Ho Kyong
2014-06-15
Fertiliser-drawn forward osmosis (FDFO) desalination has been recently studied as one feasible application of forward osmosis (FO) for irrigation. In this study, the potential of membrane scaling in the FDFO process has been investigated during the desalination of brackish groundwater (BGW). While most fertilisers containing monovalent ions did not result in any scaling when used as an FO draw solution (DS), diammonium phosphate (DAP or (NH4)2HPO4) resulted in significant scaling, which contributed to severe flux decline. Membrane autopsy using scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), and x-ray diffraction (XRD) analysis indicated that the reverse diffusion of DAP from the DS to the feed solution was primarily responsible for scale formation during the FDFO process. Physical cleaning of the membrane with deionised water at varying crossflow velocities was employed to evaluate the reversibility of membrane scaling and the extent of flux recovery. For the membrane scaled using DAP as DS, 80-90% of the original flux was recovered when the crossflow velocity for physical cleaning was the same as the crossflow velocity during FDFO desalination. However, when a higher crossflow velocity or Reynolds number was used, the flux was recovered almost completely, irrespective of the DS concentration used. This study underscores the importance of selecting a suitable fertiliser for FDFO desalination of brackish groundwater to avoid membrane scaling and severe flux decline. Copyright © 2014 Elsevier Ltd. All rights reserved.
Groundwater microbiological quality in Canadian drinking water municipal wells.
Locas, Annie; Barthe, Christine; Margolin, Aaron B; Payment, Pierre
2008-06-01
To verify previous conclusions on the use of bacterial indicators suggested in regulations and to investigate virological quality of groundwater, a 1-year study was undertaken on groundwater used as a source of drinking water in 3 provinces in Canada. Raw water from 25 municipal wells was sampled during a 1-year period for a total of 167 samples. Twenty-three sites were selected on the basis of their excellent historical bacteriological water quality data, and 2 sites with known bacteriological contamination were selected as positive controls. Water samples were analyzed for general water quality indicators (aerobic endospores, total coliforms), fecal indicators (Escherichia coli, enterococci, somatic and male-specific coliphages), total culturable human enteric viruses (determined by cell culture and immunoperoxidase), noroviruses (analyzed by reverse-transcriptase -- polymerase chain reaction (RT-PCR)), adenovirus types 40 and 41 (analyzed by integrated cell culture (ICC) - PCR), and enteroviruses and reoviruses types 1, 2, and 3 (analyzed by ICC-RT-PCR). General water quality indicators were found very occasionally at the clean sites but were frequently present at the 2 contaminated sites. Only one of 129 samples from the 23 clean sites was positive for enterococci. These results confirm the value of raw water quality historical data to detect source water contamination affecting wells that are vulnerable. Samples from the 2 contaminated sites confirmed the frequent presence of fecal indicators: E. coli was found in 20/38 samples and enterococci in 12/38 samples. Human enteric viruses were not detected by cell culture on MA-104 cells nor by immunoperoxidase detection in any sample from the clean sites but were found at one contaminated site. By ICC-RT-PCR and ICC-PCR, viruses were found by cytopathic effect in one sample from a clean site and they were found in 3 samples from contaminated sites. The viruses were not detected by the molecular methods but were confirmed as picornaviruses by electron microscopy. Noroviruses were not detected in any samples. The results obtained reinforce the value of frequent sampling of raw water using simple parameters: sampling for total coliforms and E. coli remains the best approach to detect contamination of source water by fecal pollutants and accompanying pathogens. The absence of total coliforms at a site appears to be a good indication of the absence of human enteric viruses.
NASA Astrophysics Data System (ADS)
Javad Kazemzadeh-Parsi, Mohammad; Daneshmand, Farhang; Ahmadfard, Mohammad Amin; Adamowski, Jan; Martel, Richard
2015-01-01
In the present study, an optimization approach based on the firefly algorithm (FA) is combined with a finite element simulation method (FEM) to determine the optimum design of pump and treat remediation systems. Three multi-objective functions in which pumping rate and clean-up time are design variables are considered and the proposed FA-FEM model is used to minimize operating costs, total pumping volumes and total pumping rates in three scenarios while meeting water quality requirements. The groundwater lift and contaminant concentration are also minimized through the optimization process. The obtained results show the applicability of the FA in conjunction with the FEM for the optimal design of groundwater remediation systems. The performance of the FA is also compared with the genetic algorithm (GA) and the FA is found to have a better convergence rate than the GA.
Ground-water quality protection; why it's important to you
Webbers, Ank
1995-01-01
Ground water is a valuable resource often used for industry, commerce, agriculture, and drinking water. In the 19080's, ground water provided 35 percent of the municipal water supplies in the United States and 95 percent of the rural, domestic drinking water. Scientists participating in ground-water studies may determine the potential pathways that contaminants could be transported in aquifers. In karst terrain especially, a contanimant can enter a fracture network in a carbonate aquifer and quickly spread to become a widespread health problem. Although Federal and local funding for ground-water cleanups and treatment may be available, the costs can exceed many millions of dollars each year. Such costly remedial actions could be avoided or minimized by becoming aware that ground water anywhere is vulnerable to contamination, but particularly so in carbonate terrain. Practicing good "out-of-doors" house- keeping is necessary. From the standpoint of economic and environmental responsibility, it is critical that we all work together to protect the quality of ground-water resources so that future generations can continue to have clean water.
NASA Technical Reports Server (NTRS)
Melton, Forrest S.
2017-01-01
In agricultural regions around the world, threats to water supplies from drought and groundwater depletion are driving increased demand for tools to advance agricultural water use efficiency and support sustainable groundwater management. Satellite mapping of evapotranspiration (ET) from irrigated agricultural lands can provide agricultural producers and water resource managers with information that can be used to both optimize ag water use and improve estimates of groundwater withdrawals for irrigation. We describe the development of two remote sensing-based tools for ET mapping in California, including important lessons in terms of system design, partnership development, and transition to operations. For irrigation management, the integration of satellite data and surface sensor networks to provide timely delivery of information on crop water requirements can make irrigation scheduling more practical, convenient, and accurate.Developed through a partnership between NASA and the CA Department of Water Resources, the Satellite Irrigation Management Support (SIMS) framework integrates satellite data with information from agricultural weather networks to map crop canopy development and crop water requirements at the scale of individual fields. Information is distributed to agricultural producers and water managers via a web-based interface and web data services. SIMS also provides an API that facilitates integration with other irrigation decision support tools, such as CropManage and IrriQuest. Field trials using these integrated tools have shown that they can be used to sustain yields while improving water use efficiency and nutrient management. For sustainable groundwater management, the combination of satellite-derived estimates of ET and data on surface water deliveries for irrigation can increase the accuracy of estimates of groundwater pumping. We are developing an OpenET platform to facilitate access to ET data from multiple models and accelerate operational use of ET data in support of a range of water management applications, including implementation of the Sustainable Groundwater Management Act in CA. By providing a shared basis for decision making, we anticipate that the OpenET platform will accelerate implementation of solutions for sustainable groundwater management.
NASA Astrophysics Data System (ADS)
Melton, F. S.; Huntington, J. L.; Johnson, L.; Guzman, A.; Morton, C.; Zaragoza, I.; Dexter, J.; Rosevelt, C.; Michaelis, A.; Nemani, R. R.; Cahn, M.; Temesgen, B.; Trezza, R.; Frame, K.; Eching, S.; Grimm, R.; Hall, M.
2017-12-01
In agricultural regions around the world, threats to water supplies from drought and groundwater depletion are driving increased demand for tools to advance agricultural water use efficiency and support sustainable groundwater management. Satellite mapping of evapotranspiration (ET) from irrigated agricultural lands can provide agricultural producers and water resource managers with information that can be used to both optimize ag water use and improve estimates of groundwater withdrawals for irrigation. We describe the development of two remote sensing-based tools for ET mapping in California, including important lessons in terms of system design, partnership development, and transition to operations. For irrigation management, the integration of satellite data and surface sensor networks to provide timely delivery of information on crop water requirements can make irrigation scheduling more practical, convenient, and accurate. Developed through a partnership between NASA and the CA Department of Water Resources, the Satellite Irrigation Management Support (SIMS) framework integrates satellite data with information from agricultural weather networks to map crop canopy development and crop water requirements at the scale of individual fields. Information is distributed to agricultural producers and water managers via a web-based interface and web data services. SIMS also provides an API that facilitates integration with other irrigation decision support tools, such as CropManage and IrriQuest. Field trials using these integrated tools have shown that they can be used to sustain yields while improving water use efficiency and nutrient management. For sustainable groundwater management, the combination of satellite-derived estimates of ET and data on surface water deliveries for irrigation can increase the accuracy of estimates of groundwater pumping. We are developing an OpenET platform to facilitate access to ET data from multiple models and accelerate operational use of ET data in support of a range of water management applications, including implementation of the Sustainable Groundwater Management Act in CA. By providing a shared basis for decision making, we anticipate that the OpenET platform will accelerate implementation of solutions for sustainable groundwater management.
Description and hydrogeologic evaluation of nine hazardous-waste sites in Kansas, 1984-86
Hart, R.J.; Spruill, T.B.
1988-01-01
Wastes generated at nine hazardous-waste sites in Kansas were disposed in open pits, 55-gal drums, or large storage tanks. These disposal methods have the potential to contaminate groundwater beneath the sites, the soil on the sites, and nearby surface water bodies. Various activities on the nine sites included production of diborane, transformer oil waste, production of soda ash, use of solvents for the manufacture of farm implements, reclamation of solvents and paints, oil-refinery wastes, meat packaging, and the manufacture and cleaning of tanker-truck tanks. Monitoring wells were installed upgradient and downgradient from the potential contamination source on each site. Strict decontamination procedures were followed to prevent cross contamination between well installations. Air-quality surveys were made on each site before other investigative procedures started. Hydrogeologic investigative techniques, such as terrain geophysical surveys, gamma-ray logs, and laboratory permeameter tests, were used. Groundwater level measurements provide data to determine the direction of flow. Groundwater contamination detected under the sites posed the greatest threat to the environment because of possible migration of contaminants by groundwater flow. Concentrations of volatile organic compounds, polynuclear aromatic hydrocarbons, and trace metals were detected in the groundwater at several of the sites. Many of the same compounds detected in the groundwater also were detected in soil and bed-material samples collected onsite or adjacent to the sites. Several contaminants were detected in background samples of groundwater and soil. (USGS)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guevara, K.C.; Fellinger, A.P.; Aylward, R.S.
The Department of Energy's Savannah River Site has a 60-year history of successfully operating nuclear facilities and cleaning up the nuclear legacy of the Cold War era through the processing of radioactive and otherwise hazardous wastes, remediation of contaminated soil and groundwater, management of nuclear materials, and deactivation and decommissioning of excess facilities. SRS recently unveiled its Enterprise.SRS (E.SRS) strategic vision to identify and facilitate application of the historical competencies of the site to current and future national and global challenges. E.SRS initiatives such as the initiative to Develop and Demonstrate Next generation Clean-up Technologies seek timely and mutually beneficialmore » engagements with entities around the country and the world. One such ongoing engagement is with government and industry in Japan in the recovery from the devastation of the Fukushima Daiichi Nuclear Power Station. (authors)« less
Hot spots and dark current in advanced plasma wakefield accelerators
Manahan, G. G.; Deng, A.; Karger, O.; ...
2016-01-29
Dark current can spoil witness bunch beam quality and acceleration efficiency in particle beam-driven plasma wakefield accelerators. In advanced schemes, hot spots generated by the drive beam or the wakefield can release electrons from higher ionization threshold levels in the plasma media. Likewise, these electrons may be trapped inside the plasma wake and will then accumulate dark current, which is generally detrimental for a clear and unspoiled plasma acceleration process. The strategies for generating clean and robust, dark current free plasma wake cavities are devised and analyzed, and crucial aspects for experimental realization of such optimized scenarios are discussed.
Large-Volume Resonant Microwave Discharge for Plasma Cleaning of a CEBAF 5-Cell SRF Cavity
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Mammosser, S. Ahmed, K. Macha, J. Upadhyay, M. Nikoli, S. Popovi, L. Vuakovi
2012-07-01
We report the preliminary results on plasma generation in a 5-cell CEBAF superconducting radio-frequency (SRF) cavity for the application of cavity interior surface cleaning. CEBAF currently has {approx}300 of these five cell cavities installed in the Jefferson Lab accelerator which are mostly limited by cavity surface contamination. The development of an in-situ cavity surface cleaning method utilizing a resonant microwave discharge could lead to significant CEBAF accelerator performance improvement. This microwave discharge is currently being used for the development of a set of plasma cleaning procedures targeted to the removal of various organic, metal and metal oxide impurities. These contaminantsmore » are responsible for the increase of surface resistance and the reduction of RF performance in installed cavities. The CEBAF five cell cavity volume is {approx} 0.5 m2, which places the discharge in the category of large-volume plasmas. CEBAF cavity has a cylindrical symmetry, but its elliptical shape and transversal power coupling makes it an unusual plasma application, which requires special consideration of microwave breakdown. Our preliminary study includes microwave breakdown and optical spectroscopy, which was used to define the operating pressure range and the rate of removal of organic impurities.« less
Final report for demonstration of in situ oxidation of DNAPL using the Geo-Cleanse technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jerome, K.M.; Riha, B.; Looney, B.B.
1997-09-23
At large industrial sites like the A/M Area of the Savannah River Site (SRS), undissolved dense non-aqueous phase liquid (DNAPL) in soil and groundwater is the most significant barrier to successful clean up. DNAPL acts as a reservoir that will continue to generate contaminant levels far above remediation concentration goals well into the future.
Gawaziuk, J P; Alfa, M J; Olson, N; Logsetty, S
2014-05-01
This study assesses the feasibility of using the Versajet™ system (VJS) on an inoculated pork hock (PH) skin surface sequentially for 8 days with daily cleaning and intermediate-level disinfection (ILD). Daily, PHs were inoculated with bacteria suspended in artificial test soil (ATS). An ILD protocol with accelerated hydrogen peroxide (AHP, OxivirTB(®)) was employed to clean and disinfect the VJS between debridements. PH skin contains 6.1-6.8×10(6)cfu/cm(2) bacteria. Bacterial counts in the handpiece and discharge hoses immediately after debridement of the PHs, and before cleaning, increased throughout the study period (5.19-6.43log10cfu/mL). Cleaning with the ILD protocol was reduced bacterial counts on the VJS by 6-log. Protein, a surrogate marker of organic contamination, was also reduced post-cleaning and ILD. Compared to a maximum post-debridement level of protein (57.9 μg/mL) obtained before ILD, VJS protein levels dropped to 9.8 (handpiece) and 13.8 μg/mL (discharge hose). Disinfection of the handpiece and discharge hose after debridement with AHP resulted in a 6-log reduction in bacterial count and 4.2 fold reduction in protein. An ILD protocol with an AHP may be a feasible method for serial skin surface debridements with the VJS for up to eight days. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.
Modeling Natural Attenuation of an Industrial Facility in Houston
NASA Astrophysics Data System (ADS)
Sun, D.
2016-12-01
Groundwater monitoring is currently ongoing at a commercial/industrial facility located in Deer Park, Texas (the site). The subject site is an approximate 10 acre commercial/industrial facility that began operation in the late-1970s. Operations have historically consisted of vehicle maintenance services, administrative, and equipment storage. Assessment and groundwater monitoring activities have been conducted at the site to evaluate the magnitude and extent of groundwater affected with chlorinated volatile organic compounds (VOCs). Groundwater data has been collected at this site since the mid-2000s on a quarterly basis. Presently, VOC constituents tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (DCE), 1,1-dichloroethene (1,1-DCE), and vinyl chloride (VC) are the only chemicals of concern (COCs) detected at concentrations exceeding the TCEQ Actions Levels established by the state of Texas. The goal is that one day the site will receive a certificate of completion from the state, which states that all non-responsible parties are released from all liability to the state for cleanup. The remediation technology that is currently being used at this site is Monitoring Natural Attenuation (MNA). A significant question is whether MNA is efficiently removing COCs in groundwater and how long will this process take to achieve the remediation goals. The objective of this study is to provide an estimate of concentrations of COCs in groundwater at the site using the Biochlor model. The Biochlor model will help answer the question as to whether or not natural attenuation is occurring at the site efficiently. Results show that Monitored Natural Attenuation may not be the optimal remediation technology to use at this site. Other remedial technologies are needed to clean up chemical in the site. Groundwater monitoring is currently ongoing at a commercial/industrial facility located in Deer Park, Texas (the site). The subject site is an approximate 10 acre commercial/industrial facility that began operation in the late-1970s. Operations have historically consisted of vehicle maintenance services, administrative, and equipment storage. Assessment and groundwater monitoring activities have been conducted at the site to evaluate the magnitude and extent of groundwater affected with chlorinated volatile organic compounds (VOCs). Groundwater data has been collected at this site since the mid-2000s on a quarterly basis. Presently, VOC constituents tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (DCE), 1,1-dichloroethene (1,1-DCE), and vinyl chloride (VC) are the only chemicals of concern (COCs) detected at concentrations exceeding the TCEQ Actions Levels established by the state of Texas. The goal is that one day the site will receive a certificate of completion from the state, which states that all non-responsible parties are released from all liability to the state for cleanup. The remediation technology that is currently being used at this site is Monitoring Natural Attenuation (MNA). A significant question is whether MNA is efficiently removing COCs in groundwater and how long will this process take to achieve the remediation goals. The objective of this study is to provide an estimate of concentrations of COCs in groundwater at the site using the Biochlor model. The Biochlor model will help answer the question as to whether or not natural attenuation is occurring at the site efficiently. Results show that Monitored Natural Attenuation may not be the optimal remediation technology to use at this site. Other remedial technologies are needed to clean up chemical in the site.
NASA Astrophysics Data System (ADS)
Luo, Qiankun; Wu, Jianfeng; Yang, Yun; Qian, Jiazhong; Wu, Jichun
2014-11-01
This study develops a new probabilistic multi-objective fast harmony search algorithm (PMOFHS) for optimal design of groundwater remediation systems under uncertainty associated with the hydraulic conductivity (K) of aquifers. The PMOFHS integrates the previously developed deterministic multi-objective optimization method, namely multi-objective fast harmony search algorithm (MOFHS) with a probabilistic sorting technique to search for Pareto-optimal solutions to multi-objective optimization problems in a noisy hydrogeological environment arising from insufficient K data. The PMOFHS is then coupled with the commonly used flow and transport codes, MODFLOW and MT3DMS, to identify the optimal design of groundwater remediation systems for a two-dimensional hypothetical test problem and a three-dimensional Indiana field application involving two objectives: (i) minimization of the total remediation cost through the engineering planning horizon, and (ii) minimization of the mass remaining in the aquifer at the end of the operational period, whereby the pump-and-treat (PAT) technology is used to clean up contaminated groundwater. Also, Monte Carlo (MC) analysis is employed to evaluate the effectiveness of the proposed methodology. Comprehensive analysis indicates that the proposed PMOFHS can find Pareto-optimal solutions with low variability and high reliability and is a potentially effective tool for optimizing multi-objective groundwater remediation problems under uncertainty.
Sutton, Patrick T; Ginn, Timothy R
2014-12-15
A sustainable in-well vapor stripping system is designed as a cost-effective alternative for remediation of shallow chlorinated solvent groundwater plumes. A solar-powered air compressor is used to inject air bubbles into a monitoring well to strip volatile organic compounds from a liquid to vapor phase while simultaneously inducing groundwater circulation around the well screen. An analytical model of the remediation process is developed to estimate contaminant mass flow and removal rates. The model was calibrated based on a one-day pilot study conducted in an existing monitoring well at a former dry cleaning site. According to the model, induced groundwater circulation at the study site increased the contaminant mass flow rate into the well by approximately two orders of magnitude relative to ambient conditions. Modeled estimates for 5h of pulsed air injection per day at the pilot study site indicated that the average effluent concentrations of dissolved tetrachloroethylene and trichloroethylene can be reduced by over 90% relative to the ambient concentrations. The results indicate that the system could be used cost-effectively as either a single- or multi-well point technology to substantially reduce the mass of dissolved chlorinated solvents in groundwater. Copyright © 2014 Elsevier B.V. All rights reserved.
Nonlinear ecosystem services response to groundwater availability under climate extremes
NASA Astrophysics Data System (ADS)
Qiu, J.; Zipper, S. C.; Motew, M.; Booth, E.; Kucharik, C. J.; Steven, L. I.
2017-12-01
Depletion of groundwater has been accelerating at regional to global scales. Besides serving domestic, industrial and agricultural needs, in situ groundwater is also a key control on biological, physical and chemical processes across the critical zone, all of which underpin supply of ecosystem services essential for humanity. While there is a rich history of research on groundwater effects on subsurface and surface processes, understanding interactions, nonlinearity and feedbacks between groundwater and ecosystem services remain limited, and almost absent in the ecosystem service literature. Moreover, how climate extremes may alter groundwater effects on services is underexplored. In this research, we used a process-based ecosystem model (Agro-IBIS) to quantify groundwater effects on eight ecosystem services related to food, water and biogeochemical processes in an urbanizing agricultural watershed in the Midwest, USA. We asked: (1) Which ecosystem services are more susceptible to shallow groundwater influences? (2) Do effects of groundwater on ecosystem services vary under contrasting climate conditions (i.e., dry, wet and average)? (3) Where on the landscape are groundwater effects on ecosystem services most pronounced? (4) How do groundwater effects depend on water table depth? Overall, groundwater significantly impacted all services studied, with the largest effects on food production, water quality and quantity, and flood regulation services. Climate also mediated groundwater effects with the strongest effects occurring under dry climatic conditions. There was substantial spatial heterogeneity in groundwater effects across the landscape that is driven in part by spatial variations in water table depth. Most ecosystem services responded nonlinearly to groundwater availability, with most apparent groundwater effects occurring when the water table is shallower than a critical depth of 2.5-m. Our findings provide compelling evidence that groundwater plays a vital role in sustaining ecosystem services. Our research highlights the pressing need to consider groundwater during the assessment and management of ecosystem services, and suggests that protecting groundwater resources may enhance ecosystem service resilience to future climate extremes and increased climate variability.
Using Phytoremediation to Clean Up Contamination at Military Installations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zellmer, S.D.; Hinchman, R.R.; Negri, M.C.
1997-07-01
During and following World War II, wastes from the production of munitions and other military materials were disposed of using the best available practices acceptable at that time. However, these disposal methods often contaminated soil and groundwater with organic compounds and metals that require cleanup under current regulations. An emerging technology for cleaning contaminated soils and shallow groundwater is phytoremediation, an environmentally friendly, low- cost, and low-tech process. Phytoremediation encompasses all plant- influenced biological, chemical, and physical processes that aid in the uptake, degradation, and metabolism of contaminants by either plants or free-living organisms in the plant`s rhizosphere. A phytoremediationmore » system can be viewed as a biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the soil and below-ground ecosystem for subsequent productive use. Argonne National Laboratory (ANL) has been conducting basic and applied research in phytoremediation since 1990. Initial greenhouse studies evaluated salt-tolerant wetland plants to clean UP and reduce the volume of salty `produced water` from petroleum wells. Results of these studies were used to design a bioreactor for processing produced water that is being demonstrated at a natural gas well in Oklahoma; this system can reduce produced water volume by about 75% in less than eight days, representing substantial savings in waste disposal cost. During 1994, ANL conducted a TNT plant uptake and in situ remediation study in a ridge-and-furrow area used for the disposal of pink water at the Joliet Army Ammunition Plant.« less
Squillace, P.J.; Zogorski, J.S.; Wilber, W.G.; Price, C.V.
1996-01-01
The 1990 Clean Air Act Amendments require fuel oxygenates to be added to gasoline used in some metropolitan areas to reduce atmospheric concentrations of carbon monoxide or ozone. Methyl tert-butyl ether (MTBE) is the most commonly used fuel oxygenate and is a relatively new gasoline additive. Nevertheless, out of 60 volatile organic chemicals analyzed, MTBE was the second most frequently detected chemical in samples of shallow ambient groundwater from urban areas that were collected during 1993-1994 aspart of the U.S. Geological Survey's National Water-Quality Assessment program. Samples were collected from five drinking water wells, 12 springs, and 193 monitoring wells in urban areas. No MTBE was detected in drinking water wells. At a reporting level of 0.2 ??g/L, MTBE was detected most frequently in shallow groundwater from urban areas (27% of 210 wells and springs sampled in eight areas) as compared to shallow groundwater from agricultural areas (1.3% of 549 wells sampled in 21 areas) or deeper groundwater from major aquifers (1.0% of 412 wells sampled in nine areas). Only 3% of the shallow wells sampled in urban areas had concentrations of MTBE that exceed 20 ??g/L, which is the estimated lower limit of the United States Environmental Protection Agency draft drinking water health advisory. Because MTBE is persistent and mobile in groundwater, it can move from shallow to deeper aquifers with time. In shallow urban groundwater, MTBE generally was not found with benzene, toluene, ethylbenzene, or xylene (BTEX) compounds, which commonly are associated with gasoline spills. This disassociation causes uncertainty as to the source of MTBE. Possible sources of MTBE in groundwater include point sources, such as leaking storage tanks, and non-point sources, such as recharge of precipitation and stormwater runoff.
Aligned interactions in cosmic rays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kempa, J., E-mail: kempa@pw.plock.pl
2015-12-15
The first clean Centauro was found in cosmic rays years many ago at Mt Chacaltaya experiment. Since that time, many people have tried to find this type of interaction, both in cosmic rays and at accelerators. But no one has found a clean cases of this type of interaction.It happened finally in the last exposure of emulsion at Mt Chacaltaya where the second clean Centauro has been found. The experimental data for both the Centauros and STRANA will be presented and discussed in this paper. We also present our comments to the intriguing question of the existence of a typemore » of nuclear interactions at high energy with alignment.« less
ERIC Educational Resources Information Center
Philippines Univ., Quezon City. Inst. for Science and Mathematics Education Development.
This module (recommended for grades 5 or 6) provides information on water in the community. Topics considered include: safe water (showing how clear water may be unsafe to drink); water sources; drinking water and wells; clean water underground; how water gets from the ground to the faucet inside a home; the groundwater of seaside and inland…
Wilson, Fernanda Paes; Cupples, Alison M
2016-08-01
The explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) has long been recognized as a problematic environmental pollutant, and efforts to remediate contaminated soils, sediments, and groundwater have been going on for decades. In recent years, much interest has focused on using bioremediation to clean up these sites. The current study investigated the microorganisms (16S rRNA genes, Illumina) and functional genes (xenA, xenB, and xplA) linked to RDX biodegradation in microcosms composed of sediment or groundwater from two Navy sites. For this, experiments included sediment samples from three depths (5 to 30 ft) from two wells located in one Navy site. In addition, the groundwater upstream and downstream of an emulsified oil biobarrier was examined from another Navy site. Further, for the groundwater experiments, the effect of glucose addition was explored. For the sediment experiments, the most enriched phylotypes during RDX degradation varied over time, by depth and well locations. However, several trends were noted, including the enrichment of Pseudomonas, Rhodococcus, Arthrobacter, and Sporolactobacillus in the sediment microcosms. For the groundwater-based experiments, Pseudomonas, unclassified Rhodocyclaceae, Sphingomonas, and Rhodococcus were also highly abundant during RDX degradation. The abundance of both xplA and xenA significantly increased during RDX degradation compared to the control microcosms for many treatments (both groundwater and sediment microcosms). In a limited number of microcosms, the copy number of the xenB gene increased. Phylotype data were correlated with functional gene data to highlight potentially important biomarkers for RDX biodegradation at these two Navy sites.
NASA Technical Reports Server (NTRS)
Jones, William R., Jr.; Toddy, Thomas J.; Predmore, Roamer; Shogrin, Bradley; Herrera-Fierro Pilar
1997-01-01
A parched elastohydrodynamic rig was used to determine relative bearing lifetimes as a function of cleaning procedures in a series of accelerated tests. Two ODC-free cleaning procedures (super critical CO2 and ultraviolet-ozone) were compared to a CFC-113 control. Bearings (52100 steel) were run in the counter rotating mode (equivalent to 4600 rpm) with a full complement (i.e. no retainer) and a single charge of lubricant (Krytox 143 AC). Test conditions included: an air atmosphere, 445N load, approx. 1.0 GPa mean Hertz stress. There was approximately a 50% reduction in life with bearings cleaned with UV/ozone and a 70% reduction in life with SFE CO2 when compared to the Freon control. Possible reasons for these decreases in lifetimes are presented.
NASA Technical Reports Server (NTRS)
Jones, William R., Jr.; Toddy, Thomas J.; Predmore, Roamer; Shogrin, Bradley; Herrera-Fierro, Pilar
1996-01-01
A parched elastohydrodynamic rig was used to determine relative bearing lifetimes as a function of cleaning procedures in a series of accelerated tests. Two ODC-free cleaning procedures (super critical CO2 and ultraviolet-ozone) were compared to a CFC-113 control. Bearings (52100 steel) were run in the counter rotating mode (equivalent to 4600 rpm) with a full complement (i.e. no retainer) and a single charge of lubricant (Krytox 143 AC). Test conditions included: an air atmosphere, 445 N load, approx. 1.0 GPa mean Hertz stress. There was approximately a 50% reduction in life with bearings cleaned with UV/ozone and a 70% reduction in life with SFE CO2 when compared to the Freon control. Possible reasons for these decreases in lifetimes are presented.
Groundwater protection vs. extractable soil resource usage - approaching the problem with GPR-survey
NASA Astrophysics Data System (ADS)
Kupila, J.
2012-04-01
Finland is fully self-sufficient in clean groundwater and even has a capacity of exportation: there are more than 6000 groundwater areas, a total yield of those is 5.4 million m3/day and only 10% of this is in use. Even so, nowadays the protection of groundwater has come more and more important. One of the reasons is effects of extractable soil resource usage, because the most valuable and remarkable resources of groundwater as well as sand and gravel aggregates appear in the same areas. Also in densely populated areas there is lack of aggregate products. Using the best available techniques and methods which take into account sustainable development, the outcomes of this protection vs. usage -dilemma will be beneficent. Ground penetrating radar (GPR) -survey is an efficient tool for examination of areas of groundwater and soil resources. Briefly, GPR is a geophysical method that uses radar pulses to image the subsurface. It uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum and detects the reflected signals from subsurface structures. Usually groundwater and soil aggregates appear in areas where the structure of soil layers improves the efficiency of GPR , so an exact image of subsurface layers can be outlined. Also the conditions of groundwater can be interpreted from GPR-data. Results from GPR-survey can be effective in making guidelines for extractable soil resource usage to avoid risks and to address secured sites for both groundwater and soil usage. Geological Survey of Finland has executed many co-operated projects related to these kind of problems, for example in Kainuu area, eastern Finland, 20 areas were studied with over 30 kilometers of GPR-profile. Detailed information from these researches support local authorities and actors in land use planning in future and furthermore assure safe balance in groundwater and soil resource usage.
Tandem-ESQ for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kreiner, A. J.; Escuela de Ciencia y Tecnologia, Universidad de Gral San Martin; CONICET,
2007-02-12
A folded tandem, with 1.25 MV terminal voltage, combined with an ElectroStatic Quadrupole (ESQ) chain is being proposed as a machine for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT). The machine is shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the on the 7Li(p,n)7Be reaction, to perform BNCT treatment for deep seated tumors in less than an hour.
Assessing the groundwater salinization in closed hydrologic basins due to overdraft
NASA Astrophysics Data System (ADS)
Guo, Z.; Pauloo, R.; Fogg, G. E.
2016-12-01
Population growth and the expansion of agriculture, coupled with climate uncertainties, have accelerated groundwater pumping and overdraft in alluvial aquifers worldwide. In many agricultural basins, the low rate of replenishment is far exceeded by the rate of groundwater pumping in overdrafted aquifers, which results in the substantial water table declines and in effect contributes to the formation of a "closed" basin. In fact, even modest amounts of groundwater system drawdown that do not produce what is construed as overdraft, can result in most of the groundwater discharge occurring as evapotranspiration via irrigation practices, converting the basin to a closed groundwater basin. Moreover, in past decades, extreme weather conditions (i.e., severe drought in California for the past five years) have resulted in substantially reduced surface water storage. This increases demand for groundwater to supplement low surface water supplies, and consequently, drives groundwater overdraft, and hence, groundwater salinization. In these newly closed basins, just as in other naturally closed basins such as Death Valley and the Great Salt Lake, groundwater salinity must increase not only due to evaporation, but also due to rock water interactions in the groundwater system, and lack of a natural outlet for the groundwater. In this study, the water balance and salt balance in closed basins of the Central Valley, California are computed. Groundwater degradation under the current overdraft conditions is further investigated using simple models that are developed by upscaling more complex and heterogeneous transport models. The focus of this study is to determine the applicability of these simple models to represent regional transport without explicitly including the large-scale heterogeneity inherent in the more complex models. Groundwater salinization processes, including salt accumulation caused by evapotranspiration of applied irrigation water and rock-groundwater interactions are simulated, and the time scales under which groundwater salinity may pose a threat to societies is estimated. Lastly, and most importantly, management strategies to mitigate groundwater salinization are examined.
El-Gendy, Ahmed S; Svingos, Sotero; Brice, Donald; Garretson, Joel H; Schnoor, Jerald
2009-05-01
A poplar tree-phytoremediation system was installed at former refinery and tank farm sites in Cabin Creek, West Virginia, to cleanup petroleum-contaminated-soils and groundwater. Groundwater and soils in both sites were sampled and analyzed on a regular basis to monitor changes in contaminant concentration since 1999. The concentration of benzene, toluene, ethylbenzene, xylene, and gasoline range organics (GRO) decreased an average of 81%, 90%, 67%, 78%, and 82%, respectively, in the lower soil horizons and 34%, 84%, 12%, 19%, and 59%, respectively, in groundwater. In addition, concentrations of oxygen, methane, and carbon dioxide in soil gas demonstrated that tree roots dewatered soils and allowed penetration of oxygen deep into the soil profile, creating necessary conditions for rhizosphere bioremediation. Although required clean-up time can limit phytoremediation, it has proven to be a cost-effective strategy for site improvement if imminent pathways for human exposure and risk are not an issue.
Reimann, Clemens; Banks, David
2004-10-01
Clean and healthy drinking water is important for life. Drinking water can be drawn from streams, lakes and rivers, directly collected (and stored) from rain, acquired by desalination of ocean water and melting of ice or it can be extracted from groundwater resources. Groundwater may reach the earth's surface in the form of springs or can be extracted via dug or drilled wells; it also contributes significantly to river baseflow. Different water quality issues have to be faced when utilising these different water resources. Some of these are at present largely neglected in water quality regulations. This paper focuses on the inorganic chemical quality of natural groundwater. Possible health effects, the problems of setting meaningful action levels or maximum admissible concentrations (MAC-values) for drinking water, and potential shortcomings in current legislation are discussed. An approach to setting action levels based on transparency, toxicological risk assessment, completeness, and identifiable responsibility is suggested.
Alternative designs for petroleum product storage tanks for groundwater protection.
Oke Adeleke, Samson
In developing countries, there are numerous occurrences of petroleum product spillage in groundwater. The current practice of burying storage tanks beneath the surface without adequate safety devices facilitates this phenomenon. Underground tanks rust and leak, and spilled petroleum products migrate downward. The movement of the oil in the soil depends on its viscosity and quantity, the permeability of the soil/rock, and the presence of fractures within the rock. The oil spreads laterally in the form of a thin pancake due to its lower specific gravity, and soluble components dissolve in water. The pollution plume of petroleum products and dissolved phases moves in the direction of groundwater flow in the aquifer within the pores of soil and sediments or along fractures in basement complex areas. Most communities reply heavily on groundwater for potable and industrial supplies. However, the sustainability of this resource is under threat in areas where there are filling stations as a result of significant groundwater contamination from petroleum product spillage. Drinking water becomes unpalatable when it contains petroleum products in low concentrations, and small quantities may contaminate large volumes of water. Considering the losses incurred from spillage, the cost of cleaning the aquifer, and the fact that total cleansing and attenuation is impossible, the need to prevent spillage and if it happens to prevent it from getting into the groundwater system is of paramount importance. This paper proposes alternative design procedures with a view to achieving these objectives.
Wind Power Technologies FY 2017 Budget At-A-Glance
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
2016-03-01
The Wind Program accelerates U.S. deployment of clean, affordable, and reliable domestic wind power through research, development, and demonstration activities. These advanced technology investments directly contribute to the goals for the United States to generate 80% of the nation’s electricity from clean, carbon-free energy sources by 2035; reduce carbon emissions 26%-28% below 2005 levels by 2025; and reduce carbon emissions 80% by 2050 by reducing costs and increasing performance of wind energy systems.
NASA Astrophysics Data System (ADS)
Kupila, Juho
2016-04-01
Finland is fully self-sufficient in clean groundwater and even has a capacity of exportation. There are approx. 6000 groundwater areas with a total yield of 5.4 million m3/day. Currently only 10% of this groundwater resource is in use. For the efficient and safe exploitation of these areas in the future, detailed modeling of soil structure is an important method in groundwater surveys. 3D -models improve the general knowledge of linkage between land use planning and groundwater protection. Results can be used as a base information in water supply service development and when performing the measures needed in case of environmental accidents. Also, when creating the groundwater flow models the collected information is utilized and is usually the main data source. Geological Survey of Finland has carried out soil structure studies in co-operation with authorities, municipalities and the local water suppliers. The main objectives of these projects are to determine the geological structure of groundwater area for estimating the validity of the present exclusion area, the quantity of ground water volume and recharge capability and possible risks to the groundwater. Research areas are usually under an active water supply service. Kauvonkangas groundwater area is located in the municipality of Tervola, in Southern part of Finnish Lapland. Extent of the area is 7.9 km2 and it is an important water source for the local and nearby population centers. There are two active water supply companies in the area. Field studies in the project will include general geological and hydrological mapping, soil drilling with observation pipe installation, test pumping and water sampling. Geophysical measures will play a key-role, including ground penetrating radar (GPR) and gravimetric measurements. Studies will be carried out in spring and summer 2016. The main results will be the models of the bedrock and groundwater level and main characteristics of the soil layers in the area. Results will also include the main flow directions of the groundwater. Structure models will be done with Groundhog -software. Kauvonkangas -project is funded by local water supply companies Meri-Lapin Vesi and Tervolan Vesi, Ministry of Agriculture and Forestry, and Geological Survey of Finland.
Bibliography of ground-water references for all 254 counties in Texas, 1886-2001
Baker, E.T.
2005-01-01
PrefaceThis bibliography comprises more than 10,000 citations of ground-water references involving all 254 counties in Texas. The reference citations date from 1886 and extend into 2001. Publications and reports from more than 30 agencies, universities, water districts, geological societies, cities, consultants, and private publication outlets are included in the bibliography. The bibliographic listing is, first, alphabetical by county and, second, chronological by date of the report, from oldest to most recent. The passing years have seen a proliferation in both published and unpublished reports, and such proliferation continues to expand at an accelerating pace. All 254 counties have had groundwater studies, either cursory or detailed. Investigation and development of the ground-water resources of the State of Texas resulted in reports that appear in a variety of formats, including Federal, State, and local agency reports; scholarly, professional, and trade journals; conference proceedings; guidebooks; maps; and theses and dissertations. The end result for the person seeking ground-water information about specific Texas counties is the increasing difficulty in locating pertinent data among the many and diverse ground-water reports in which the information is recorded. This bibliography, covering a span of 115 years, should have considerable utility in guiding those individuals seeking ground-water information.
NASA Astrophysics Data System (ADS)
Weber, M. C.; Ward, A. S.; Muste, M.
2014-12-01
The salinization of groundwater resources is a widespread problem in arid agricultural environments. In Mewat District (Haryana, India), groundwater salinity has rendered much of the accessible supply unfit for human consumption or agriculture. Historically, this closed basin retained fresh pockets of water at the foothills of the Aravalli Hills, where monsoonal precipitation runoff from the mountains was recharged through infiltration or facilitated by man-made structures. To date, an increasing number of pumps supply the region with fresh water for consumption and agriculture leading to shrinking the freshwater zone at an accelerated pace. The potential for increased human consumption corroborated with the effects of climate change bring uncertainty about the future of water security for the Mewat communities, most of them critically bound to the existence of local water. This study addresses the sustainability of the freshwater supply under a range of land interventions and climate scenarios, using a 2-D groundwater flow and transport model. Our results quantify potential futures for this arid, groundwater-dependent location, using numerical groundwater modeling to quantify interactions between human water use, infrastructure, and climate. Outcomes of this modeling study will inform an NGO active in the area on sustainable management of groundwater resources.
Permafrost thaw in a nested groundwater-flow system
McKenzie, Jeffery M.; Voss, Clifford I.
2013-01-01
Groundwater flow in cold regions containing permafrost accelerates climate-warming-driven thaw and changes thaw patterns. Simulation analyses of groundwater flow and heat transport with freeze/thaw in typical cold-regions terrain with nested flow indicate that early thaw rate is particularly enhanced by flow, the time when adverse environmental impacts of climate-warming-induced permafrost loss may be severest. For the slowest climate-warming rate predicted by the Intergovernmental Panel on Climate Change (IPCC), once significant groundwater flow begins, thick permafrost layers can vanish in several hundred years, but survive over 1,000 years where flow is minimal. Large-scale thaw depends mostly on the balance of heat advection and conduction in the supra-permafrost zone. Surface-water bodies underlain by open taliks allow slow sub-permafrost flow, with lesser influence on regional thaw. Advection dominance over conduction depends on permeability and topography. Groundwater flow around permafrost and flow through permafrost impact thaw differently; the latter enhances early thaw rate. Air-temperature seasonality also increases early thaw. Hydrogeologic heterogeneity and topography strongly affect thaw rates/patterns. Permafrost controls the groundwater/surface-water-geomorphology system; hence, prediction and mitigation of impacts of thaw on ecology, chemical exports and infrastructure require improved hydrogeology/permafrost characterization and understanding
NASA Astrophysics Data System (ADS)
Mladenov, N.; Kulkarni, H. V.; McKnight, D. M.; Zheng, Y.; Kirk, M. F.
2016-12-01
It was demonstrated more than two decades ago that the electron shuttling ability of fulvic acids (FA) accelerates iron (Fe) reduction. However, the environmental relevance of this mechanism for arsenic-laden groundwater environments has thus far only been hypothesized. Here we show that FAs isolated from high and low arsenic groundwater aquifers in the Bengal Basin can act to shuttle electrons between bacteria and Fe(III). Bangladesh groundwater FAs were reduced by Geobacter metallireducens and were subsequently capable of abiotically reducing Fe(III) to Fe(II). Moreover, all four Bangladesh groundwater FAs investigated in the study had higher Fe(III) to Fe(II) conversion rates compared to anthraquinone disulfonate, an oxidized quinone, and Suwannee River Fulvic Acid, a commercially-available FA isolated from a terrestrially-dominated surface water source. Until now, microbially-mediated reductive dissolution of Fe (oxy)hydroxides, driven by the availability of labile organic matter, was widely accepted as the main control on arsenic mobilization in reducing aquifers. Our evidence for the electron shuttling ability of Bangladesh FAs implicates electron shuttling as another important control on elevated As concentrations in groundwater of the Bengal Basin.
Cleaning Process Development for Metallic Additively Manufactured Parts
NASA Technical Reports Server (NTRS)
Tramel, Terri L.; Welker, Roger; Lowery, Niki; Mitchell, Mark
2014-01-01
Additive Manufacturing of metallic components for aerospace applications offers many advantages over traditional manufacturing techniques. As a new technology, many aspects of its widespread utilization remain open to investigation. Among these are the cleaning processes that can be used for post finishing of parts and measurements to verify effectiveness of the cleaning processes. Many cleaning and drying processes and measurement methods that have been used for parts manufactured using conventional techniques are candidates that may be considered for cleaning and verification of additively manufactured parts. Among these are vapor degreasing, ultrasonic immersion and spray cleaning, followed by hot air drying, vacuum baking and solvent displacement drying. Differences in porosity, density, and surface finish of additively manufactured versus conventionally manufactured parts may introduce new considerations in the selection of cleaning and drying processes or the method used to verify their effectiveness. This presentation will review the relative strengths and weaknesses of different candidate cleaning and drying processes as they may apply to additively manufactured metal parts for aerospace applications. An ultrasonic cleaning technique for exploring the cleanability of parts will be presented along with an example using additively manufactured Inconel 718 test specimens to illustrate its use. The data analysis shows that this ultrasonic cleaning approach results in a well-behaved ultrasonic cleaning/extraction behavior. That is, it does not show signs of accelerated cavitation erosion of the base material, which was later confirmed by neutron imaging. In addition, the analysis indicated that complete cleaning would be achieved by ultrasonic immersion cleaning at approximately 5 minutes, which was verified by subsequent cleaning of additional parts.
100-D Ponds closure plan. Revision 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petersen, S.W.
1997-09-01
The 100-D Ponds is a Treatment, Storage, and Disposal (TSD) unit on the Hanford Facility that received both dangerous and nonregulated waste. This Closure Plan (Rev. 1) for the 100-D Ponds TSD unit consists of a RCRA Part A Dangerous Waste Permit Application (Rev. 3), a RCRA Closure Plan, and supporting information contained in the appendices to the plan. The closure plan consists of eight chapters containing facility description, process information, waste characteristics, and groundwater monitoring data. There are also chapters containing the closure strategy and performance standards. The strategy for the closure of the 100-D Ponds TSD unit ismore » clean closure. Appendices A and B of the closure plan demonstrate that soil and groundwater beneath 100-D Ponds are below cleanup limits. All dangerous wastes or dangerous waste constituents or residues associated with the operation of the ponds have been removed, therefore, human health and the environment are protected. Discharges to the 100-D Ponds, which are located in the 100-DR-1 operable unit, were discontinued in June 1994. Contaminated sediment was removed from the ponds in August 1996. Subsequent sampling and analysis demonstrated that there is no contamination remaining in the ponds, therefore, this closure plan is a demonstration of clean closure.« less
RFI to CMS: An Approach to Regulatory Acceptance of Site Remediation Technologies
NASA Technical Reports Server (NTRS)
Rowland, Martin A.
2001-01-01
Lockheed Martin made a smooth transition from RCRA Facility Investigation (RFI) at the National Aeronautics and Space Administrations'(NASA) Michoud Assembly Facility (MA-F) to its Corrective Measures Study (CMS) phase within the RCRA Corrective Action Process. We located trichloroethylene (TCE) contamination that resulted from the manufacture of the Apollo Program Saturn V rocket and the Space Shuttle External Tank, began the cleanup, and identified appropriate technologies for final remedies. This was accomplished by establishing a close working relationship with the state environmental regulatory agency through each step of the process, and resulted in receiving approvals for each of those steps. The agency has designated Lockheed Martin's management of the TCE-contamination at the MAF site as a model for other manufacturing sites in a similar situation. In February 1984, the Louisiana Department of Environmental Quality (LDEQ) issued a compliance order to begin the clean up of groundwater contaminated with TCE. In April 1984 Lockheed Martin began operating a groundwater recovery well to capture the TCE plume. The well not only removes contaminants, but also sustains an inward groundwater hydraulic gradient so that the potential offsite migration of the TCE plume is greatly diminished. This effort was successful, and for the agency to give orders and for a regulated industry to follow them is standard procedure, but this is a passive approach to solving environmental problems. The goal of the company thereafter was to take a leadership, proactive role and guide the MAF contamination clean up to its best conclusion at minimum time and lowest cost to NASA. To accomplish this goal, we have established a positive working relationship with LDEQ, involving them interactively in the implementation of advanced remedial activities at MAF as outlined in the following paragraphs.
A new AMS facility at Inter University Accelerator Centre, New Delhi
NASA Astrophysics Data System (ADS)
Kumar, Pankaj; Chopra, S.; Pattanaik, J. K.; Ojha, S.; Gargari, S.; Joshi, R.; Kanjilal, D.
2015-10-01
Inter University Accelerator Centre (IUAC), a national facility of government of India, is having a 15UD Pelletron accelerator for multidisciplinary ion beam based research programs. Recently, a new accelerator mass spectrometry (AMS) facility has been developed after incorporating many changes in the existing 15UD Pelletron accelerator. A clean chemistry laboratory for 10Be and 26Al with all the modern facilities has also been developed for the chemical processing of samples. 10Be measurements on sediment samples, inter laboratory comparison results and 26Al measurements on standard samples are presented in this paper. In addition to the 10Be and 26Al AMS facilities, a new 14C AMS facility based on a dedicated 500 kV tandem ion accelerator with two cesium sputter ion sources, is also being setup at IUAC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sharma, Ritin; Dill, Brian; Chourey, Karuna
2012-01-01
The expanding use of surfactants for proteome sample preparations has prompted the need to systematically optimize the application and removal of these MS-deleterious agents prior to proteome measurements. Here we compare four different detergent clean-up methods (Trichloroacetic acid (TCA) precipitation, Chloroform/Methanol/Water (CMW) extraction, commercial detergent removal spin column method (DRS) and filter-aided sample preparation(FASP)) with respect to varying amounts of protein biomass in the samples, and provide efficiency benchmarks with respect to protein, peptide, and spectral identifications for each method. Our results show that for protein limited samples, FASP outperforms the other three clean-up methods, while at high protein amountmore » all the methods are comparable. This information was used in a dual strategy of comparing molecular weight based fractionated and unfractionated lysates from three increasingly complex samples (Escherichia coli, a five microbial isolate mixture, and a natural microbial community groundwater sample), which were all lysed with SDS and cleaned up using FASP. The two approaches complemented each other by enhancing the number of protein identifications by 8%-25% across the three samples and provided broad pathway coverage.« less
NASA Astrophysics Data System (ADS)
Bonacci, Ognjen; Roje-Bonacci, Tanja
2010-05-01
Construction of grout curtains in karst terrains is primarily connected with dams and reservoirs. Their role is to increase watertightness and prevent progressive erosion. In this presentation hourly continuous measurement of groundwater level in two deep piezometers near the Đale reservoir is analysed. The Đale reservoir in the Cetina River began operation in 1989. The total length of the grout curtain is 3.9 km. It spreads 120 m bellow the Đale dam. First analysed piezometer A is drilled in the interior part of the system, between the reservoir and the grout curtain, while the second one B is located in its external part. Distance between them is 200 m. In natural conditions, prior the grout curtain construction, groundwater level fluctuation in both of them was similar (practically the same). Construction of the grout curtain extremely changed groundwater behaviour in each of them. During the six month of continuous monitoring, differences between groundwater levels in them range between +19.86 m (groundwater in B is lower than in A) and -12.77 m (groundwater in A is lower than in B). During the 77% of analysed period the groundwater level in interior piezometer A is higher than the groundwater level in external piezometer B. In other 23% of analysed period the groundwater level in outside piezometer B is higher than in inside A. The construction of the grout curtain caused unnaturally high hydrostatic gradients, which can accelerate the dissolutional expansion of karst fractures. As a result, unbearable leakage of the reservoir Đale can occur over its lifetime. Careful analyses of groundwater level behaviour discover some other very important characteristics of karst underground morphology.
Liu, Fei; Song, Xianfang; Yang, Lihu; Han, Dongmei; Zhang, Yinghua; Ma, Ying; Bu, Hongmei
2015-12-15
Groundwater resources are increasingly exploited for industrial and agricultural purposes in many arid regions globally, it is urgent to gain the impact of the enhanced anthropogenic pressure on the groundwater chemistry. The aim of this study was to acquire a comprehensive understanding of the evolution of groundwater chemistry and to identify the impact of natural and anthropogenic factors on the groundwater chemistry in the Subei Lake basin, Northwestern China. A total of 153 groundwater samples were collected and major ions were measured during the three campaigns (August and December 2013, May 2014). At present, the major hydrochemical facies in unconfined groundwater are Ca-Mg-HCO3, Ca-Na-HCO3, Na-Ca-HCO3, Na-HCO3, Ca-Mg-SO4 and Na-SO4-Cl types, while the main hydrochemical facies in confined groundwater are Ca-Mg-HCO3, Ca-Na-HCO3, Na-Ca-HCO3, Ca-HCO3 and Na-HCO3 types. Relatively greater seasonal variation can be observed in the chemical constituents of confined groundwater than that of unconfined groundwater. Rock weathering predominates the evolution of groundwater chemistry in conjunction with the cation exchange, and the dissolution/precipitation of gypsum, halite, feldspar, calcite and dolomite are responsible for the chemical constituents of groundwater. Anthropogenic activities can be classified as: (1) groundwater overexploitation; (2) excessive application of fertilizers in agricultural areas. Due to intensive groundwater pumping, the accelerated groundwater mineralization resulted in the local changes in hydrochemical facies of unconfined groundwater, while the strong mixture, especially a large influx of downward leakage from the unconfined aquifer into the confined aquifer, played a vital role in the fundamental variation of hydrochemical facies in confined aquifer. The nitrate contamination is mainly controlled by the local hydrogeological settings coupled with the traditional flood irrigation. The deeper insight into geochemical evolution of groundwater obtained from this study can be beneficial to improving groundwater management for sustainable development in the rapidly industrialized areas. Copyright © 2015 Elsevier B.V. All rights reserved.
Self-cleaning geopolymer concrete - A review
NASA Astrophysics Data System (ADS)
Norsaffirah Zailan, Siti; Mahmed, Norsuria; Bakri Abdullah, Mohd Mustafa Al; Sandu, Andrei Victor
2016-06-01
Concrete is the most widely used construction materials for building technology. However, cement production releases high amounts of carbon dioxide (CO2) to the atmosphere that leads to increasing the global warming. Thus, an alternative, environmental friendly construction material such as geopolymer concrete has been developed. Geopolymer concrete applies greener alternative binder, which is an innovative construction material that replaces the Portland cement. This technology introduced nano-particles such as nanoclay into the cement paste in order to improve their mechanical properties. The concrete materials also have been developed to be functioned as self-cleaning construction materials. The self-cleaning properties of the concrete are induced by introducing the photocatalytic materials such as titania (TiO2) and zinc oxide (ZnO). Self-cleaning concrete that contains those photocatalysts will be energized by ultraviolet (UV) radiation and accelerates the decomposition of organic particulates. Thus, the cleanliness of the building surfaces can be maintained and the air surrounding air pollution can be reduced. This paper briefly reviews about self-cleaning concrete.
Contribution of the backstreaming ions to the Self-Magnetic pinch (SMP) diode current
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mazarakis, Michael G.; Cuneo, Michael E.; Fournier, Sean D.
2016-08-08
Summary form only given. The results presented here were obtained with an SMP diode mounted at the front high voltage end of the RITS accelerator. RITS is a Self-Magnetically Insulated Transmission Line (MITL) voltage adder that adds the voltage pulses of six 1.3 MV inductively insulated cavities. Our experiments had two objectives: first to measure the contribution of the back-streaming ion currents emitted from the anode target to the diode beam current, and second to try to evaluate the energy of those ions and hence the actual Anode-Cathode (A-K) gap actual voltage. In any very high voltage inductive voltage addermore » (IVA) utilizing MITLs to transmit the power to the diode load, the precise knowledge of the accelerating voltage applied on the anode-cathode (A-K) gap is problematic. The accelerating voltage quoted in the literature is from estimates based on measurements of the anode and cathode currents of the MITL far upstream from the diode and utilizing the para-potential flow theories and inductive corrections. Thus it would be interesting to have another independent measurement to evaluate the A-K voltage. The diode's anode is made of a number of high Z metals in order to produce copious and energetic flash x-rays. The backstreaming currents are a strong fraction of the anode materials and their stage of cleanness and gas adsorption. We have measured the back-streaming ion currents emitted from the anode and propagating through a hollow cathode tip for various diode configurations and different techniques of target cleaning treatments, such as heating to very high temperatures with DC and pulsed current, with RF plasma cleaning and with both plasma cleaning and heating. Finally, we have also evaluated the A-K gap voltage by ion filtering techniques.« less
Qualification of local advanced cryogenic cleaning technology for 14nm photomask fabrication
NASA Astrophysics Data System (ADS)
Taumer, Ralf; Krome, Thorsten; Bowers, Chuck; Varghese, Ivin; Hopkins, Tyler; White, Roy; Brunner, Martin; Yi, Daniel
2014-10-01
The march toward tighter design rules, and thus smaller defects, implies stronger surface adhesion between defects and the photomask surface compared to past generations, thereby resulting in increased difficulty in photomask cleaning. Current state-of-the-art wet clean technologies utilize functional water and various energies in an attempt to produce similar yield to the acid cleans of previous generations, but without some of the negative side effects. Still, wet cleans have continued to be plagued with issues such as persistent particles and contaminations, SRAF and feature damages, leaving contaminants behind that accelerate photo-induced defect growth, and others. This paper details work done through a design of experiments (DOE) utilized to qualify an improved cryogenic cleaning technology for production in the Advanced Mask Technology Center (AMTC) advanced production lines for 20 and 14 nm processing. All work was conducted at the AMTC facility in Dresden, Germany utilizing technology developed by Eco-Snow Systems and RAVE LLC for their cryogenic local cleaning VC1200F platform. This system uses a newly designed nozzle, improved gaseous CO2 delivery, extensive filtration to remove hydrocarbons and minimize particle adders, and other process improvements to overcome the limitations of the previous generation local cleaning tool. AMTC has successfully qualified this cryogenic cleaning technology and is currently using it regularly to enhance production yields even at the most challenging technology nodes.
The sinking Mekong delta; modeling 25 years of groundwater extraction and subsidence
NASA Astrophysics Data System (ADS)
Minderhoud, P. S. J.; Erkens, G.; Pham, H. V.; Bui, V. T.; Erban, L. E.; Kooi, H.; Stouthamer, E.
2017-12-01
The Vietnamese Mekong delta, the third's largest delta in the world, is experiencing annual subsidence rates up to several centimeters. As a result, vulnerability to flooding and storm surges, salinization and, ultimately, permanent inundation increases. Extraction of groundwater from the soft deltaic subsurface can be a major driving mechanism of subsidence, however a quantification of temporal and spatial impact to subsidence in the Mekong delta was not done yet. We developed a delta-wide, 3D hydrogeological model coupled to a 1D geotechnical module to quantify the contribution of excessive groundwater exploitation to subsidence. The modelling period of 25 years captures the period in which the hydrogeological state of the delta transforming from almost undisturbed to a situation with increasing aquifer depletion. Our model provides a quantitative spatially-explicit assessment of groundwater extraction-induced subsidence for the entire Mekong delta since the start of widespread depletion of the groundwater reserves. Over the past decades subsidence related to groundwater extraction has accelerated towards the highest sinking rates at present. During the past 25 years, the delta sank on average 18 cm, with areas over 30 cm. Currently the delta experiences an average subsidence rate of 1.1 cm yr-1, some areas subside over 2.5 cm yr-1, due to groundwater exploitation. These rates outpace global sea level rise almost by an order of magnitude. Given the increasing trends in groundwater demand in the delta, the current rates are likely to increase in the near future.
Modeling Effects of Groundwater Basin Closure, and Reversal of Closure, on Groundwater Quality
NASA Astrophysics Data System (ADS)
Pauloo, R.; Guo, Z.; Fogg, G. E.
2017-12-01
Population growth, the expansion of agriculture, and climate uncertainties have accelerated groundwater pumping and overdraft in aquifers worldwide. In many agricultural basins, a water budget may be stable or not in overdraft, yet disconnected ground and surface water bodies can contribute to the formation of a "closed" basin, where water principally exits the basin as evapotranspiration. Although decreasing water quality associated with increases in Total Dissolved Solids (TDS) have been documented in aquifers across the United States in the past half century, connections between water quality declines and significant changes in hydrologic budgets leading to closed basin formation remain poorly understood. Preliminary results from an analysis with a regional-scale mixing model of the Tulare Lake Basin in California indicate that groundwater salinization resulting from open to closed basin conversion can operate on a decades-to-century long time scale. The only way to reverse groundwater salinization caused by basin closure is to refill the basin and change the hydrologic budget sufficiently for natural groundwater discharge to resume. 3D flow and transport modeling, including the effects of heterogeneity based on a hydrostratigraphic facies model, is used to explore rates and time scales of groundwater salinization and its reversal under different water and land management scenarios. The modeling is also used to ascertain the extent to which local and regional heterogeneity need to be included in order to appropriately upscale the advection-dispersion equation in a basin scale groundwater quality management model. Results imply that persistent managed aquifer recharge may slow groundwater salinization, and complete reversal may be possible at sufficiently high water tables.
Water availability and land subsidence in the Central Valley, California, USA
NASA Astrophysics Data System (ADS)
Faunt, Claudia C.; Sneed, Michelle; Traum, Jon; Brandt, Justin T.
2016-05-01
The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007-2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.
Water availability and land subsidence in the Central Valley, California, USA
Faunt, Claudia; Sneed, Michelle; Traum, Jonathan A.; Brandt, Justin
2016-01-01
The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007–2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.
High contrast ion acceleration at intensities exceeding 10{sup 21} Wcm{sup −2}
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dollar, F.; Zulick, C.; Matsuoka, T.
2013-05-15
Ion acceleration from short pulse laser interactions at intensities of 2×10{sup 21}Wcm{sup −2} was studied experimentally under a wide variety of parameters, including laser contrast, incidence angle, and target thickness. Trends in maximum proton energy were observed, as well as evidence of improvement in the acceleration gradients by using dual plasma mirrors over traditional pulse cleaning techniques. Extremely high efficiency acceleration gradients were produced, accelerating both the contaminant layer and high charge state ions from the bulk of the target. Two dimensional particle-in-cell simulations enabled the study of the influence of scale length on submicron targets, where hydrodynamic expansion affectsmore » the rear surface as well as the front. Experimental evidence of larger electric fields for sharp density plasmas is observed in simulation results as well for such targets, where target ions are accelerated without the need for contaminant removal.« less
Quantitative cleaning characterization of a lithium-fluoride ion diode
DOE Office of Scientific and Technical Information (OSTI.GOV)
Menge, P.R.; Cuneo, M.E.
An ion source cleaning testbed was created to test plasma-cleaning techniques, and to provide quantitative data on plasma-cleaning protocols prior to implementation on the SABRE accelerator. The testbed was designed to resolve issues regarding the quantity of contaminants absorbed by the anode source (LiF), and the best cleaning methodology. A test chamber was devised containing a duplicate of the SABRE diode. Radio-frequency (RF) power was fed to the anode, which was isolated from ground and thus served as the plasma discharge electrode. RF plasma discharges in 1--3 mtorr of Ar with 10% O{sub 2} were found to provide the bestmore » cleaning of the LiF surface. X-ray photoelectron spectroscopy (XPS) showed that the LiF could accrue dozens of monolayers of carbon just by sitting in a 2 {times} 10{sup {minus}5} vacuum for 24 h. Tests of various discharge cleaning protocols indicated that 15 min of an Ar/O{sub 2} discharge was sufficient to reduce this initial 13--45 monolayers of carbon impurities to 2--4 monolayers. Rapid recontamination of the LiF was also observed. Up to ten monolayers of carbon returned in 2 min after termination of the plasma discharge and subsequent pumping back to the 10{sup {minus}5} torr range. Heating of the LiF also was found to provide anode cleaning. Application of heating combined with plasma cleaning provided the highest cleaning rates.« less
CLASSIFYING COASTAL WATERS: HISTORICAL PERSPECTIVE AND CURRENT FOCUS ON AQUATIC STRESSORS
Coastal ecosystems are ecologically and commercially productive habitats that are experiencing significant impacts associated with accelerated population growth in coastal zones. The Clean Water Act requires identification of impaired water bodies and determination of the causes ...
Open Energy Info (OpenEI) (Fact Sheet)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
2010-12-01
The Open Energy Information (OpenEI.org) initiative is a free, open-source, knowledge-sharing platform. OpenEI was created to provide access to data, models, tools, and information that accelerate the transition to clean energy systems through informed decisions.
Sabol, M.A.; Turney, G.L.; Ryals, G.N.
1988-01-01
Gas Works Park, in Seattle, Washington, is located at the site of an abandon gasification plant on Lake Union. Wastes deposited during 50 years of plant operations (1906-1956) have extended the shore line 100 ft and left the park soil contaminated with a number of hazardous material. Soil contaminants include polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls, pesticides, volatile organic compounds, cyanide, and metals. PAHs and metals have been detected in Lake Union sediments. Maximum total PAH concentrations exceeded 100 million micrograms/kilogram in some places in the soils of the park at 6-inch depths and in some lake sediments. Other contaminants present are much lower in concentrations. The park is on glacial drift overlain by gasification waste materials and clean fill. Waste materials include sand and gravels, mixed with lampblack, oil, bricks, and other industrial wastes. Groundwater flows through the soils and waste toward Lake Union. Vertical groundwater movement is uncertain, but is assumed to be upward near Lake Union. Concentrations of most soil contaminants are probably low in the groundwater and in Lake Union due to the low solubilities and high sorptive characteristics of these contaminants. However, no water quality data are available to confirm this premise. (USGS)
The Slow Moving Threat of Groundwater Salinization: Mechanisms, Costs, and Adaptation Strategies
NASA Astrophysics Data System (ADS)
Pauloo, R.; Guo, Z.; Fogg, G. E.
2016-12-01
Population growth, the Green Revolution, and climate uncertainties have accelerated overdraft in groundwater basins worldwide, which in some regions is converting these basins into closed hydrologic systems, where the dominant exits for water are evapotranspiration and pumping. Irrigated agricultural basins are particularly at risk to groundwater salinization, as naturally occurring (i.e., sodium, potassium, chloride) and anthropogenic (i.e., nitrate fertilizers) salts leach back into the water table through the root zone, while a large portion of pumped groundwater leaves the system as it is evapotranspired by crops. Decreasing water quality associated with increases in Total Dissolved Solids (TDS) has been documented in aquifers across the United States in the past half century. This study suggests that the increase in TDS in aquifers can be partially explained by closed basin hydrogeology and rock-water interactions leading to groundwater salinization. This study will present: (1) a report on historical water quality in the Tulare basin, (2) a forward simulation of salt balance in Tulare Basin based on the Department of Water Resources numerical model C2VSim, and a simple mixing model, (3) an economic analysis forecasting the cost of desalination under varying degrees of managed groundwater recharge where the basin is gradually filled, avoiding hydraulic closure.
Environmental Impact From Accelerator Operation at SLAC
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, James C
1999-03-22
Environmental impacts from electron accelerator operations at the Stanford Linear Accelerator Center, which is located near populated areas, are illustrated by using examples of three different accelerator facilities: the low power (a few watts) SSRL, the high power (a few kilowatts) PEP-II, and the 50-kW SLC. Three types of major impacts are discussed: (1) off-site doses from skyshine radiation, mainly neutrons, (2) off-site doses from radioactive air emission, mainly {sup 13}N, and (3) radioactivities, mainly {sup 3}H, produced in the groundwater. It was found that, from SSRL operation, the skyshine radiation result in a MEI (Maximum Exposed Individual) of 0.3more » {mu}Sv/y while a conservative calculation using CAP88 showed a MEI of 0.36 {mu}Sv/y from radioactive air releases. The calculated MEI doses due to future PEP-II operation are 30 {mu}Sv/y from skyshine radiation and 2 {mu}Sv/y from air releases. The population doses due to radioactive air emission are 0.5 person-mSv from SSRL and 12 person-mSv from PEP-II. Because of the stronger decrease of skyshine dose as the distance increases, the population dose from skyshine radiation are smaller than that from air release. The third environmental impact, tritium activity produced in the groundwater, was also demonstrated to be acceptable from both the well water measurements and the FLUKA calculations for the worst case of the SLC high-power dump.« less
Němeček, Jan; Steinová, Jana; Špánek, Roman; Pluhař, Tomáš; Pokorný, Petr; Najmanová, Petra; Knytl, Vladislav; Černík, Miroslav
2018-05-01
In situ bioremediation (ISB) using reductive dechlorination is a widely accepted but relatively slow approach compared to other technologies for the treatment of groundwater contaminated by chlorinated ethenes (CVOCs). Due to the known positive kinetic effect on microbial metabolism, thermal enhancement may be a viable means of accelerating ISB. We tested thermally enhanced ISB in aquifers situated in sandy saprolite and underlying fractured granite. The system comprised pumping, heating and subsequent injection of contaminated groundwater aiming at an aquifer temperature of 20-30°C. A fermentable substrate (whey) was injected in separate batches. The test was monitored using hydrochemical and molecular tools (qPCR and NGS). The addition of the substrate and increase in temperature resulted in a rapid increase in the abundance of reductive dechlorinators (e.g., Dehalococcoides mccartyi, Dehalobacter sp. and functional genes vcrA and bvcA) and a strong increase in CVOC degradation. On day 34, the CVOC concentrations decreased by 87% to 96% in groundwater from the wells most affected by the heating and substrate. On day 103, the CVOC concentrations were below the LOQ resulting in degradation half-lives of 5 to 6days. Neither an increase in biomarkers nor a distinct decrease in the CVOC concentrations was observed in a deep well affected by the heating but not by the substrate. NGS analysis detected Chloroflexi dechlorinating genera (Dehalogenimonas and GIF9 and MSBL5 clades) and other genera capable of anaerobic metabolic degradation of CVOCs. Of these, bacteria of the genera Acetobacterium, Desulfomonile, Geobacter, Sulfurospirillum, Methanosarcina and Methanobacterium were stimulated by the substrate and heating. In contrast, groundwater from the deep well (affected by heating only) hosted representatives of aerobic metabolic and aerobic cometabolic CVOC degraders. The test results document that heating of the treated aquifer significantly accelerated the treatment process but only in the case of an abundant substrate. Copyright © 2017. Published by Elsevier B.V.
Squillace, P.T.; Zogorski, J.S.; Wilber, W.G.; Price, C.V.
1997-01-01
The 1990 Clean Air Act Amendments require fuel oxygenates to be added to gasoline used in some metropolitan areas to reduce atmospheric concentrations of carbon monoxide or ozone. Methyl tert-butyl ether (MTBE), is the most commonly used fuel oxygenate and is a relatively new gasoline additive. Nevertheless, out of 60 volatile organic chemicals analyzed, MTBE was the second most frequently detected chemical in samples of shallow ambient groundwater from urban areas that were collected during 1993-94 as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Samples were collected from 5 drinking-water wells, 12 springs, and 1g3 monitoring wells in urban areas. No MTBE was detected in drinking-water wells. At a reporting level of 0.2 ??g/L, MTBE was detected most frequently in shallow groundwater from urban areas (27% of 210 wells and springs sampled in 8 areas) as compared to shallow groundwater from agricultural areas (1.3% of 549 wells sampled in 21 areas) or deeper groundwater from major aquifers (1.0% of 412 wells sampled in 9 areas). Only 3% of the shallow wells sampled in urban areas had concentrations of MTBE that exceed 20 ??g/L, which is the estimated lower limit of the United States Environmental Protection Agency draft lifetime drinking water health advisory. Because MTBE is persistent and mobile in groundwater) it can move from shallow to deeper aquifers with time. In shallow urban groundwater, MTBE generally was not found with benzene, toluene, ethylbenzene, or xylenes (BTEX) compounds which commonly are associated with gasoline spills. This disassociation causes uncertainty as to the source of MTBE. Possible sources of MTBE in groundwater include point sources, such as leaking storage tanks, and nonpoint sources, such as recharge of precipitation and storm-water runoff.
Gillip, Jonathan A.
2014-01-01
The West Gulf Coastal Plain, Mississippi embayment, and underlying Cretaceous aquifers are rich in water resources; however, large parts of the aquifers are largely unusable because of large concentrations of dissolved solids. Cretaceous aquifers are known to have large concentrations of salinity in some parts of Arkansas. The Nacatoch Sand and the Tokio Formation of Upper Cretaceous age were chosen for investigation because these aquifers produce groundwater to wells near their outcrops and have large salinity concentrations away from their outcrop areas. Previous investigations have indicated that dissolved-solids concentrations of groundwater within the Nacatoch Sand, 2–20 miles downdip from the outcrop, render the groundwater as unusable for purposes requiring freshwater. Groundwater within the Tokio Formation also exhibits large concentrations of dissolved solids downdip. Water-quality data showing elevated dissolved-solids concentrations are limited for these Cretaceous aquifers because other shallower aquifers are used for water supply. Although not suitable for many uses, large, unused amounts of saline groundwater are present in these aquifers. Historical borehole geophysical logs were used to determine the geologic and hydrogeologic properties of these Cretaceous aquifers, as well as the quality of the groundwater within the aquifers. Based on the interpretation of borehole geophysical logs, in Arkansas, the altitude of the top of the Nacatoch Sand ranges from more than 200 to less than -4,000 feet; the structural high occurs in the outcrop area and the structural low occurs in southeastern Arkansas near the Desha Basin structural feature. The thickness of the Nacatoch Sand ranges from 0 to over 550 feet. The minimum thickness occurs where the formation pinches out in the outcrop area, and the maximum thickness occurs in the southwestern corner of Arkansas. Other areas of large thickness include the area of the Desha Basin structural feature in southeastern Arkansas and in an area on the border of Cross and St. Francis Counties in eastern Arkansas. The clean-sand percentage of the total Nacatoch Sand thickness ranges from less than 20 percent to more than 60 percent and generally decreases downdip. The Nacatoch Sand contains more than 120.5 million acre-feet of water with a dissolved-solids concentration between 1,000 and 10,000 milligrams per liter (mg/L), more than 57.5 million acre-feet of water with a dissolved-solids concentration between 10,000 and 35,000 mg/L, and more than 122.5 million acre-feet of water with a dissolved-solids concentration more than 35,000 mg/L. The altitude of the top of the Tokio Formation, in Arkansas, ranges from more than 200 feet to less than -4,400 feet; the structural high occurs in the outcrop area and the structural low occurs in southeastern Arkansas near the Desha Basin structural feature. The thickness of the Tokio Formation, in Arkansas, ranges from 0 to over 400 feet. The minimum thickness occurs where the formation pinches out in the outcrop area, and the maximum thickness occurs in the southwestern corner of Arkansas. The clean-sand percentage of the total Tokio Formation thickness ranges from less than 20 percent to more than 60 percent and generally decreases away from the outcrop area. The Tokio Formation contains more than 2.5 million acre-feet of water with a dissolved-solids concentration between 1,000 and 10,000 mg/L, more than 12.5 million acre-feet of water with a dissolved-solids concentration between 10,000 and 35,000 mg/L, and nearly 43.5 million acre-feet of water with a dissolved-solids concentration more than 35,000 mg/L.
NITRATE POLLUTION IN SHALLOW GROUNDWATER OF A HARD ROCK REGION IN SOUTH CENTRAL INDIA
NASA Astrophysics Data System (ADS)
Brindha, K.; Rajesh, R.; Murugan, R.; Elango, L.
2009-12-01
Groundwater forms a major source of drinking water in most parts of the world. Due to the lack of piped drinking water supply, the population in rural areas depend on the groundwater resources for domestic purposes. Hence, the quality of groundwater in such regions needs to be monitored regularly. Presence of high concentration of nitrate in groundwater used for drinking is a major problem in many countries as it causes health related problems. Most often infants are affected by the intake of high nitrate in drinking water and food. The present study was carried out with the objective of assessing the nitrate concentration in groundwater and determining the causes for nitrate in groundwater in parts of Nalgonda district in India which is located at a distance of about 135 km towards ESE direction from Hyderabad. Nitrate concentration in groundwater of this area was analysed by collecting groundwater samples from forty six representative wells. Samples were collected once in two months from March 2008 to March 2009. A total of 244 groundwater samples were collected during the study. Soil samples were collected from fifteen locations during May 2009 and the denitrifying bacteria were isolated from the soil using spread plate method. The nitrate concentration in groundwater samples were analysed in the laboratory using Metrohm 861 advanced compact ion chromatograph using appropriate standards. The highest concentration of nitrate recorded during the sampling period was 879.65mg/l and the lowest concentration was below detection limit. The maximum permissible limit of nitrate for drinking water as per Bureau of Indian Standards is 45mg/l. About 13% of the groundwater samples collected from this study area possessed nitrate concentration beyond this limit. The nitrate concentration was high in the southeastern part of the study area. This implies that the nitrate concentration in groundwater tends to increase along the flow direction. Application of fertilizers is one of the sources for nitrate in groundwater. The recharge of rainwater through the indiscriminately dumped animal wastes also adds to nitrate in groundwater. As the population of denitrifying microbes (Agrobacterium sp.) in the topsoil increased, the nitrate concentration in groundwater decreased. The wells in the investigated region have been demarcated into safe and unsafe wells for consumption of water with respect to nitrate. The quality of groundwater in this region must be improved by denitrifying the groundwater before using it for consumption. Reduced dependence on nitrogen-rich fertilizers can also lower the influx of nitrates to a large extent. As the dumping of animal waste is also a reason behind high nitrate in groundwater, it would be better to use them as a biofertilizer. Due to the detrimental biological effects of nitrate, treatment and prevention methods must be considered to protect groundwater aquifers from nitrate leaching. Moreover, it is also important to educate the local population about keeping their surroundings clean, alternate use of the animal waste (as fuel) and to follow hygienic sanitation practices.
Noble Gas Thermometry and Hydrologic Ages: Evidence for Late Holocene Warming in Southwest Texas
NASA Astrophysics Data System (ADS)
Castro, M.; Goblet, P.
2003-12-01
Paleoclimatic reconstruction through the use of noble gases dissolved in groundwater has been the object of numerous studies in recent years. Unlike many other continental temperature proxies, noble gases have the advantage of providing direct information on atmospheric temperatures at the time rainwater penetrated the ground and joined a particular groundwater reservoir. In recent years, new methods for determination of noble gas temperatures have been developed, which provide a high level of accuracy on such temperature estimations. The issue of paleoclimatic reconstruction through noble gases however, is not only one of accurate temperature determination, but also one of accurate water age estimation so that a correct correspondence between noble gas temperatures and groundwater age can be established and proper paleoclimatic reconstruction attempted. The typical approach to estimate groundwater ages has been based on computing water travel times along streamlines from the recharge to the observation point taking into account only advection. This approach is limited because, like any other tracer, the movement of water in porous media is also affected by cinematic dispersion and molecular diffusion. We have therefore undertaken the formulation of hydrologic models that yield significantly better constraints on groundwater ages in the Carrizo aquifer and surrounding formations of south Texas, where noble gas temperatures have already been determined. To account for groundwater mixing we treat age as one would treat a solute concentration. In order to simulate groundwater ages we used a finite element model of groundwater flow that has been validated by 4He and 3He. The finite model spans a 120.6 Km cross-section between altitudes of +220m and -2210 m, and comprises 58,968 elements and 31,949 nodes. Combination of these newly calculated water ages and previously reported noble gas temperatures reveals new aspects of late Pleistocene and Holocene climate in southwestern Texas, in particular, an abrupt late Holocene temperature increase previously unidentified through 14C dating. Temperature increased by up to 3.4° C in the first half of the last millennium and by 1.5° C between ˜5.6 and 3.7 kyrs BP. More important than the resolution of individual paleoclimate episodes is the identification of a slow cooling trend between ˜1,200 kyrs and ˜200 kyrs, a trend that accelerates during the late Pleistocene and early Holocene. This cooling trend gives way to an extremely rapid increase in temperature in the late Holocene. Such abrupt warming seems to have accelerated in the last millennium and seems to continue at present. This temperature increase is the most striking feature arising from the determination of new groundwater ages.
Non-aqueous cleaning solvent substitution
NASA Technical Reports Server (NTRS)
Meier, Gerald J.
1994-01-01
A variety of environmental, safety, and health concerns exist over use of chlorinated and fluorinated cleaning solvents. Sandia National Laboratories, Lawrence Livermore National Laboratories, and the Kansas City Division of AlliedSignal have combined efforts to focus on finding alternative cleaning solvents and processes which are effective, environmentally safe, and compliant with local, state, and federal regulations. An alternative solvent has been identified, qualified, and implemented into production of complex electronic assemblies, where aqueous and semi-aqueous cleaning processes are not allowed. Extensive compatibility studies were performed with components, piece-parts, and materials. Electrical testing and accelerated aging were used to screen for detrimental, long-term effects. A terpene, d-limonene, was selected as the solvent of choice, and it was found to be compatible with the components and materials tested. A brief history of the overall project will be presented, along with representative cleaning efficiency results, compatibility results, and residual solvent data. The electronics industry is constantly searching for proven methods and environmentally-safe materials to use in manufacturing processes. The information in this presentation will provide another option to consider on future projects for applications requiring high levels of quality, reliability, and cleanliness from non-aqueous cleaning processes.
Groundwater and Air Contamination: Risk, Toxicity, Exposure Assessment, Policy, and Regulation
NASA Astrophysics Data System (ADS)
Watts, R. J.; Teel, A. L.
2003-12-01
The improper disposal of hazardous wastes and subsequent contamination of surface and groundwaters has exposed the public and ecosystems to toxic chemicals that have detrimental consequences. The cost of cleaning up the thousands of hazardous waste sites throughout the world is daunting, and the effort to do so is economically impractical. As a result, some level of contamination will always remain, both locally and globally. The presence of a residual level of contamination carries with it the probability of negative impacts on the world's population; e.g., enhanced risk of cancer or the onset of neurological disorders. Risk is the probability of such events. Risk assessments are routinely performed at contaminated sites and in areas of widespread environmental contamination, such as an entire aquifer, as a means of quantifying the potential threats to public health and to ecosystems.
Groundwater cleanup demonstrations at Complex 34, CCAS
NASA Technical Reports Server (NTRS)
2000-01-01
At Launch Complex 34, Greg Beyke, with Current Environmental Solutions, talks to representatives from environmental and federal agencies about the environmental research project that involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA in a groundwater cleanup effort. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program, which used the complex, in the 60s. The group formed the Interagency NDAPL Consortium (IDC) to study three contamination cleanup technologies: Six Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. KSC hosted a two-day conference that presented information and demonstrations of the three technologies being tested at the site.
Groundwater cleanup demonstrations at Complex 34, CCAS
NASA Technical Reports Server (NTRS)
2000-01-01
At Launch Complex 34, the Six-Phase Soil Heating site that is involved in a groundwater cleanup project can be seen. The project involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program, which used the complex, in the 60s. The group formed the Interagency NDAPL Consortium (IDC) to study three contamination cleanup technologies: Six-Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. In the background is the block house for the complex. KSC hosted a two-day conference that presented information and demonstrations of the three technologies being tested at the site.
Groundwater cleanup demonstrations at Complex 34, CCAS
NASA Technical Reports Server (NTRS)
2000-01-01
At Launch Complex 34, representatives from environmental and Federal agencies head for the block house during presentations about the environmental research project that involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA in a groundwater cleanup effort. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program, which used the complex, in the 60s. The group formed the Interagency NDAPL Consortium (IDC) to study three contamination cleanup technologies: Six Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. KSC hosted a two-day conference that presented information and demonstrations of the three technologies being tested at the site.
The Effects of Groundwater Samplers on Water Quality. A Literature Review
1993-10-01
Nacht 1983): borehole and sampler di- devices operate by applying negative pressure, ameter, sampling depth, ease of cleaning, initial or vacuum, at...come in contact with any atmospheric gases al. 1974, Barcelona et al. 1985) have shown that and are subject to only a slight negative pressure...and selenium. They felt the degassing was due to 20% for the three most volatile compounds at the partial vacuum exerted by the pump for lift, highest
Jinpeng, Zhang; Limin, Liu; Futao, Zhang; Junzhi, Cao
2018-04-04
With cement, bentonite, water glass, J85 accelerator, retarder and water as raw materials, a new composite grouting material used to seal groundwater inflow and reinforce wall rock in deep fractured rock mass was developed in this paper. Based on the reaction mechanism of raw material, the pumpable time, stone rate, initial setting time, plastic strength and unconfined compressive strength of multi-group proportion grouts were tested by orthogonal experiment. Then, the optimum proportion of composite grouting material was selected and applied to the grouting engineering for sealing groundwater inflow and reinforcing wall rock in mine shaft lining. The results show the mixing proportion of the maximum pumpable time, maximum stone rate and minimum initial setting time of grout are A K4 B K1 C K4 D K2 , A K3 B K1 C K1 D K4 and A K3 B K3 C K4 D K1 , respectively. The mixing proportion of the maximum plastic strength and unconfined compressive strength of grouts concretion bodies are A K1 B K1 C K1 D K3 and A K1 B K1 C K1 D K1 , respectively. Balanced the above 5 indicators overall and determined the optimum proportion of grouts: bentonite-cement ratio of 1.0, water-solid ratio of 3.5, accelerator content of 2.9% and retarder content of 1.45%. This new composite grouting material had good effect on the grouting engineering for sealing groundwater inflow and reinforcing wall rock in deep fractured rock mass.
Zhou, Hai; He, Ming; Li, Jing; Chen, Liang; Huang, Zhifeng; Zheng, Shaoyan; Zhu, Liya; Ni, Erdong; Jiang, Dagang; Zhao, Bingran; Zhuang, Chuxiong
2016-11-22
Hybrid rice breeding offers an important strategy to improve rice production, in which the cultivation of a male sterile line is the key to the success of cross-breeding. CRISPR/Cas9 systems have been widely used in target-site genome editing, whereas their application for crop genetic improvement has been rarely reported. Here, using the CRISPR/Cas9 system, we induced specific mutations in TMS5, which is the most widely applied thermo-sensitive genic male sterility (TGMS) gene in China, and developed new "transgene clean" TGMS lines. We designed 10 target sites in the coding region of TMS5 for targeted mutagenesis using the CRISPR/Cas9 system and assessed the potential rates of on- and off-target effects. Finally, we established the most efficient construct, the TMS5ab construct, for breeding potentially applicable "transgene clean" TGMS lines. We also discussed factors that affect the editing efficiency according to the characteristics of different target sequences. Notably, using the TMS5ab construct, we developed 11 new "transgene clean" TGMS lines with potential applications in hybrid breeding within only one year in both rice subspecies. The application of our system not only significantly accelerates the breeding of sterile lines but also facilitates the exploitation of heterosis.
Machine Learning for Mapping Groundwater Salinity with Oil Well Log Data
NASA Astrophysics Data System (ADS)
Chang, W. H.; Shimabukuro, D.; Gillespie, J. M.; Stephens, M.
2016-12-01
An oil field may have thousands of wells with detailed petrophysical logs, and far fewer direct measurements of groundwater salinity. Can the former be used to extrapolate the latter into a detailed map of groundwater salinity? California Senate Bill 4, with its requirement to identify Underground Sources of Drinking Water, makes this a question worth answering. A well-known obstacle is that the basic petrophysical equations describe ideal scenarios ("clean wet sand") and even these equations contain many parameters that may vary with location and depth. Accounting for other common scenarios such as high-conductivity shaly sands or low-permeability diatomite (both characteristic of California's Central Valley) causes parameters to proliferate to the point where the model is underdetermined by the data. When parameters outnumber data points, however, is when machine learning methods are most advantageous. We present a method for modeling a generic oil field, where groundwater salinity and lithology are depth series parameters, and the constants in petrophysical equations are scalar parameters. The data are well log measurements (resistivity, porosity, spontaneous potential, and gamma ray) and a small number of direct groundwater salinity measurements. Embedded in the model are petrophysical equations that account for shaly sand and diatomite formations. As a proof of concept, we feed in well logs and salinity measurements from the Lost Hills Oil Field in Kern County, California, and show that with proper regularization and validation the model makes reasonable predictions of groundwater salinity despite the large number of parameters. The model is implemented using Tensorflow, which is an open-source software released by Google in November, 2015 that has been rapidly and widely adopted by machine learning researchers. The code will be made available on Github, and we encourage scrutiny and modification by machine learning researchers and hydrogeologists alike.
Bayless, E. Randall; Arihood, Leslie D.; Fowler, Kathleen K.
2011-01-01
The Green Valley reclaimed coal refuse site, near Terre Haute, Ind., was mined for coal from 1948 to 1963. Subsurface coal was cleaned and sorted at land surface, and waste material was deposited over the native glacial till. Approximately 2.7 million cubic yards of waste was deposited over 159 acres (92.3 hectares) in tailings ponds and gob piles. During 1993, the Indiana Department of Natural Resources, Division of Reclamation, improved the site by grading gob piles, filling tailings ponds, and covering the refuse with a layer of glacial drift. During 2008, the Division of Reclamation and U.S. Geological Survey initiated a cooperative investigation to characterize the hydrogeology of the site and construct a calibrated groundwater flow model that could be used to simulate the results of future remedial actions. In support of the modeling, a data-collection network was installed at the Green Valley site to measure weather components, geophysical properties, groundwater levels, and stream and seep flow. Results of the investigation indicate that (1) there is negligible overland flow from the site, (2) the prevailing groundwater-flow direction is from northeast to southwest, with a much smaller drainage to the northeast, (3) there is not a direct hydraulic connection between the refuse and West Little Sugar Creek, (4) about 24 percent of the groundwater recharge emerges through seeps, and water from the seeps evaporates or eventually flows to West Little Sugar Creek and the Green Valley Mine Pond, and (5) about 72 percent of groundwater recharge moves vertically downward from the coal refuse into the till and follows long, slow flow paths to eventual dischage points.
Rao, N Subba
2011-05-01
Fluoride (F(-)) is essential for normal bone growth, but its higher concentration in the drinking water poses great health problems and fluorosis is common in many parts of India. The present paper deals with the aim of establishment of facts of the chemical characteristics responsible for the higher concentration of F(-) in the groundwater, after understanding the chemical behavior of F(-) in relation to pH, total alkalinity (TA), total hardness (TH), carbonate hardness (CH), non-carbonate hardness (NCH), and excess alkalinity (EA) in the groundwater observed from the known areas of endemic fluorosis zones of Andhra Pradesh that have abundant sources of F(-)-bearing minerals of the Precambrians. The chemical data of the groundwater shows that the pH increases with increase F(-); the concentration of TH is more than the concentration of TA at low F(-) groundwater, the resulting water is represented by NCH; the TH has less concentration compared to TA at high F(-) groundwater, causing the water that is characterized by EA; and the water of both low and high concentrations of F(-) has CH. As a result, the F(-) has a positive relation with pH and TA, and a negative relation with TH. The operating mechanism derived from these observations is that the F(-) is released from the source into the groundwater by geochemical reactions and that the groundwater in its flowpath is subjected to evapotranspiration due to the influence of dry climate, which accelerates a precipitation of CaCO(3) and a reduction of TH, and thereby a dissolution of F(-). Furthermore, the EA in the water activates the alkalinity in the areas of alkaline soils, leading to enrichment of F(-). Therefore, the alkaline condition, with high pH and EA, and low TH, is a more conducive environment for the higher concentration of F(-) in the groundwater.
NASA Astrophysics Data System (ADS)
Onodera, S.; Saito, M.; Maruyama, Y.; Jin, G.; Miyaoka, K.; Shimizu, Y.
2013-12-01
In coastal megacities, sever groundwater depression and water pollution occurred. These impacts affected to river environment change. Especially, the river mouth area has been deposited the polluted matters. These areas have characteristics of water level fluctuation which causes river water-groundwater interaction and the associated change in dynamics of nutrients. However, these effects on the nutrient transport in tidal reaches and nutrient load to the sea have not been fully evaluated in previous studies. Therefore, we aimed to clarify the characteristics of the nutrient transport with the river water-groundwater interaction in the tidal river of Osaka metropolitan city. We conducted the field survey from the river mouth to the 7km upstream area of Yamato River, which has a length of 68km and a watershed area of 1070 km2. Spatial variations in radon (222Rn) concentrations and the difference of hydraulic potential between river waters and the pore waters suggest that the groundwater discharges to the river channel in the upstream area. In contrast, the river water recharged into the groundwater near the river mouth area. It may be caused by the lowering of groundwater level associated with the excess abstraction of groundwater in the urban area. The result also implies the seawater intrusion would accelerate the salinization of groundwater. The spatial and temporal variations in nutrient concentrations indicate that nitrate-nitrogen (NO3-N) concentrations changed temporally and it negative correlated with dissolved organic nitrogen (DON) concentrations. Inorganic phosphorous (PO4-P) concentrations showed the increasing trend with the increase of the river water level. Based on the mass balance, nutrient reproduction from the river bed was suggested in tidal reach. That was estimated to be 10 % of total nitrogen and 3% of phosphorus loads from the upstream.
NREL National Bioenergy Center Overview
Foust, Thomas; Pienkos, Phil; Sluiter, Justin; Magrini, Kim; McMillan, Jim
2018-01-16
The demand for clean, sustainable, secure energy is growing... and the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is answering the call. NREL's National Bioenergy Center is pioneering biofuels research and development and accelerating the pace these technologies move into the marketplace.
Assessing the Groundwater Concentrations and Geographical Distribution of Arsenic in Nepal
NASA Astrophysics Data System (ADS)
Ma, J.; Liu, F.
2015-12-01
Arsenic 33As, one of the major groundwater contaminants, occurs in both natural and anthropogenic forms. Arsenic inhibits cellular respiration and the production of ATP in human body. Prolonged intake of non-lethal quantities of arsenic can cause cancer and diseases in vital organs such as the heart, liver, skin, and kidney. Each year, millions of people in the rural areas of Bangladesh, India, and other developing countries in South Asia are exposed to arsenic-poisoned groundwater. According to the World Health Organization, arsenic levels in drinking water should not exceed 10 parts per billion; however, the levels of arsenic found in groundwater in the heavily contaminated regions are often more than ten times of the recommended limit. Nepal is one of these regions. In most of the rural areas in Nepal, there is no infrastructure to produce clean filtered water, and wells thus became the major source. However, most of these wells were dug without testing for groundwater safety, because the test commands resources that the rural communities do not have access to. This is also limited data published on Nepal's groundwater contaminant levels. The scarcity of information prohibits the international community from recognizing the severity of arsenic poisoning in Nepal and coming up with the most efficient measures to help. With this project, we will present a method to determine groundwater safety by analyzing geologic data and using remote sensing. The original source of arsenic is the arsenic-bearing minerals in the sediments. Some geological formations have higher arsenic levels than others due to their depositional environments. Therefore, by using existing geologic data from Nepal and countries with similar types of arsenic contamination, we hope to determine correlations between areas where there are reports of high concentrations of arsenic in groundwater to the environmental factors that may cause a particular concentration of arsenic. Furthermore, with deeper understanding of the correlations, we can predict whether an area is suffering from arsenic laden groundwater without actual field testing. We use R and ArcGIS to conduct the statistical and geographical analysis in this project.
NASA Astrophysics Data System (ADS)
Alameddine, Ibrahim; Jawhari, Gheeda; El-Fadel, Mutasem
2017-04-01
Perceptions developed by consumers regarding the quality of water reaching their household can affect the ultimate use of the water. This study identified key factors influencing consumers' perception of water quality in a highly urbanized coastal city, experiencing chronic water shortages, overexploitation of groundwater, and accelerated saltwater intrusion. Household surveys were administered to residents to capture views and perceptions of consumed water. Concomitantly, groundwater and tap water samples were collected and analyzed at each residence for comparison with perceptions. People's rating of groundwater quality was found to correlate to the measured water quality both in the dry and wet seasons. In contrast, perceptions regarding the water quality of the public water supply network did not show any correlation with the measured tap water quality indicators. Logistic regression models developed to predict perception based on salient variables indicated that age, apartment ownership, and levels of total dissolved solids play a significant role in shaping perceptions regarding groundwater quality. Perceptions concerning the water quality of the public water supply network appeared to be independent of the measured total dissolved solids levels at the tap but correlated to those measured in the wells. The study highlights misconceptions that can arise as a result of uncontrolled cross-connections of groundwater to the public supply network water and the development of misaligned perceptions based on prior consumption patterns, water shortages, and a rapidly salinizing groundwater aquifer.
Alameddine, Ibrahim; Jawhari, Gheeda; El-Fadel, Mutasem
2017-04-01
Perceptions developed by consumers regarding the quality of water reaching their household can affect the ultimate use of the water. This study identified key factors influencing consumers' perception of water quality in a highly urbanized coastal city, experiencing chronic water shortages, overexploitation of groundwater, and accelerated saltwater intrusion. Household surveys were administered to residents to capture views and perceptions of consumed water. Concomitantly, groundwater and tap water samples were collected and analyzed at each residence for comparison with perceptions. People's rating of groundwater quality was found to correlate to the measured water quality both in the dry and wet seasons. In contrast, perceptions regarding the water quality of the public water supply network did not show any correlation with the measured tap water quality indicators. Logistic regression models developed to predict perception based on salient variables indicated that age, apartment ownership, and levels of total dissolved solids play a significant role in shaping perceptions regarding groundwater quality. Perceptions concerning the water quality of the public water supply network appeared to be independent of the measured total dissolved solids levels at the tap but correlated to those measured in the wells. The study highlights misconceptions that can arise as a result of uncontrolled cross-connections of groundwater to the public supply network water and the development of misaligned perceptions based on prior consumption patterns, water shortages, and a rapidly salinizing groundwater aquifer.
NASA Astrophysics Data System (ADS)
Cendon, D. I.; Hankin, S. I.; Hughes, C. E.; Meredith, K.; Peterson, M.; Scheiber, L.; Shimizu, Y.
2016-12-01
Most groundwater isotopic studies are limited to one snapshot in time due to high costs associated with sampling and analytical procedures. The timing of sampling within long-term seasonal climatic cycles may affect interpretations, particularly in unconfined or semi-confined aquifer systems. To test the potential influence of decadal climatic trends, particularly on groundwater residence time, we have combined results from a multi-year sampling programme. Hydrogeochemistry and isotopic tracer analysis including H2O stable isotopes, δ13CDIC, 3H, 14CDIC for all samples and 87Sr/86Sr and NO3-δ15N, have been applied to groundwater recovered from the Kulnura - Mangrove Mountain aquifer hosted by a weathered sandstone plateau within the Sydney Basin (Australia). In general, the study area is characterised by alternating dry and wet periods that can be prolonged as they are linked to wider climatic events such as El Niño, La Niña and modulated by the Indian Ocean Dipole. The region experienced above average rainfall from 1985-1990 followed by generally drier conditions (1991-2007) and slightly wetter conditions to 2015. Groundwater results from the first years (2006-2010), under generally dry conditions resulted in lower groundwater levels, revealed important inter-annual variations. These are interpreted to be locally driven by groundwater extraction, resulting in a progressive influx of modern groundwater. The progressive input of modern water has exposed deeper parts of the aquifer to increased NO3- concentrations of anthropogenic origin. The change in chemistry of the groundwater, particularly the lowering of groundwater pH, has accelerated the dissolution of carbonate mineral phases that in turn affects 14C residence time assessments. Subsequent sampling results (2012-2015), under higher rainfall conditions, suggest modern recharge in areas previously without measurable tritium activities. The complex interplay between recharge, anthropogenic influences and climate may be further complicated by the local irregularities in the sandstone weathering profile and the transition to preferential groundwater fracture-flow with depth.
Remediation of Groundwater Contaminated by Nuclear Waste
NASA Astrophysics Data System (ADS)
Parker, Jack; Palumbo, Anthony
2008-07-01
A Workshop on Accelerating Development of Practical Field-Scale Bioremediation Models; An Online Meeting, 23 January to 20 February 2008; A Web-based workshop sponsored by the U.S. Department of Energy Environmental Remediation Sciences Program (DOE/ERSP) was organized in early 2008 to assess the state of the science and knowledge gaps associated with the use of computer models to facilitate remediation of groundwater contaminated by wastes from Cold War era nuclear weapons development and production. Microbially mediated biological reactions offer a potentially efficient means to treat these sites, but considerable uncertainty exists in the coupled biological, chemical, and physical processes and their mathematical representation.
The Grand Challenge of Basin-Scale Groundwater Quality Management Modelling
NASA Astrophysics Data System (ADS)
Fogg, G. E.
2017-12-01
The last 50+ years of agricultural, urban and industrial land and water use practices have accelerated the degradation of groundwater quality in the upper portions of many major aquifer systems upon which much of the world relies for water supply. In the deepest and most extensive systems (e.g., sedimentary basins) that typically have the largest groundwater production rates and hold fresh groundwaters on decadal to millennial time scales, most of the groundwater is not yet contaminated. Predicting the long-term future groundwater quality in such basins is a grand scientific challenge. Moreover, determining what changes in land and water use practices would avert future, irreversible degradation of these massive freshwater stores is a grand challenge both scientifically and societally. It is naïve to think that the problem can be solved by eliminating or reducing enough of the contaminant sources, for human exploitation of land and water resources will likely always result in some contamination. The key lies in both reducing the contaminant sources and more proactively managing recharge in terms of both quantity and quality, such that the net influx of contaminants is sufficiently moderate and appropriately distributed in space and time to reverse ongoing groundwater quality degradation. Just as sustainable groundwater quantity management is greatly facilitated with groundwater flow management models, sustainable groundwater quality management will require the use of groundwater quality management models. This is a new genre of hydrologic models do not yet exist, partly because of the lack of modeling tools and the supporting research to model non-reactive as well as reactive transport on large space and time scales. It is essential that the contaminant hydrogeology community, which has heretofore focused almost entirely on point-source plume-scale problems, direct it's efforts toward the development of process-based transport modeling tools and analyses capable of appropriately upscaling advection-dispersion and reactions at the basin scale (10^2 km). A road map for research and development in groundwater quality management modeling and its application toward securing future groundwater resources will be discussed.
Long-term groundwater depletion in the United States
Konikow, Leonard F.
2015-01-01
The volume of groundwater stored in the subsurface in the United States decreased by almost 1000 km3 during 1900–2008. The aquifer systems with the three largest volumes of storage depletion include the High Plains aquifer, the Mississippi Embayment section of the Gulf Coastal Plain aquifer system, and the Central Valley of California. Depletion rates accelerated during 1945–1960, averaging 13.6 km3/year during the last half of the century, and after 2000 increased again to about 24 km3/year. Depletion intensity is a new parameter, introduced here, to provide a more consistent basis for comparing storage depletion problems among various aquifers by factoring in time and areal extent of the aquifer. During 2001–2008, the Central Valley of California had the largest depletion intensity. Groundwater depletion in the United States can explain 1.4% of observed sea-level rise during the 108-year study period and 2.1% during 2001–2008. Groundwater depletion must be confronted on local and regional scales to help reduce demand (primarily in irrigated agriculture) and/or increase supply.
Ex-Situ Remediation Technologies for Environmental Pollutants: A Critical Perspective.
Kuppusamy, Saranya; Palanisami, Thavamani; Megharaj, Mallavarapu; Venkateswarlu, Kadiyala; Naidu, Ravi
2016-01-01
Pollution and the global health impacts from toxic environmental pollutants are presently of great concern. At present, more than 100 million people are at risk from exposure to a plethora of toxic organic and inorganic pollutants. This review is an exploration of the ex-situ technologies for cleaning-up the contaminated soil, groundwater and air emissions, highlighting their principles, advantages, deficiencies and the knowledge gaps. Challenges and strategies for removing different types of contaminants, mainly heavy metals and priority organic pollutants, are also described.
Cecconet, D; Devecseri, M; Callegari, A; Capodaglio, A G
2018-02-01
Nitrates have been detected in groundwater worldwide, and their presence can lead to serious groundwater use limitations, especially because of potential health problems. Amongst different options for their removal, bioelectrochemical systems (BESs) have achieved promising results; in particular, attention has raised on BES-driven autotrophic denitrification processes. In this work, the performance of a microbial electrolysis cell (MEC) for groundwater autotrophic denitrification, is assessed in different conditions of nitrate load, hydraulic retention time (HRT) and process configuration. The system obtained almost complete nitrate removal under all conditions, while nitrite accumulation was recorded at nitrate loads higher than 100mgNO 3 - L -1 . The MEC system achieved, in different tests, a maximum nitrate removal rate of 62.15±3.04gNO 3 - -Nm -3 d -1 , while the highest TN removal rate observed was 35.37±1.18gTNm -3 d -1 . Characteristic of this process is a particularly low (in comparison with other reported works) energy consumption: 3.17·10 -3 ±2.26·10 -3 kWh/gNO 3 - N removed and 7.52·10 -2 ±3.58·10 -2 kWhm -3 treated. The anolyte configuration in closed loop allowed the process to use less clean water, while guaranteeing identical performances as in other conventional configurations. Copyright © 2017 Elsevier B.V. All rights reserved.
Lu, Qiang; Luo, Qi Shi; Li, Hui; Liu, Yong Di; Gu, Ji Dong; Lin, Kuang Fei; Fei Lin, Kuang
2015-01-01
CAHs, as a cleaning solvent, widely contaminated shallow groundwater with the development of manufacturing in China's Yangtze River Delta. This study focused on the distribution of CAHs, and correlations between CAHs and environmental variables in a shallow groundwater in Shanghai, using kriging interpolation and multifactorial analysis. The results showed that the overall CAHs plume area (above DIV) was approximately 9,000 m(2) and located in the 2-4 m underground, DNAPL was accumulated at an area of approximately 1,400 m(2) and located in the 6-8m sandy silt layer on the top of the muddy silty clay. Heatmap of PPC for CAHs and environmental variables showed that the correlation between "Fe(2+)" and most CAHs such as "1,1,1-TCA", "1,1-DCA", "1,1-DCE" and "%TCA" were significantly positive (p<0.001), but "%CA" and/or "%VC" was not, and "Cl-" was significantly positive correlated with "1,1-DCA" and "1,1-DCE" (p<0.001). The PCA demonstrated that the relative proportions of CAHs in groundwater were mostly controlled by the sources and the natural attenuation. In conclusion, the combination of geographical and chemometrics was helpful to establishing an aerial perspective of CAHs and identifying reasons for the accumulation of toxic dechlorination intermediates, and could become a useful tool for characterizing contaminated sites in general.
NASA Astrophysics Data System (ADS)
Yahya, Hameed Saleh Ali; Jilali, Abdelhakim; Mostareh, Mohammed Mohammed Mohammed; Chafik, Zouheir; Chafi, Abdelhafid
2017-12-01
The focus of this study is the physicochemical and bacteriological characteristics of groundwater in the Triffa plain, Morocco. In total, 34 groundwater samples were analyzed for major elements (Tp, pH, EC, K+, Na+, Ca2+, Mg2+, Cl-, SO4 2-, NO3 -, NO2 -, NH4 +, H2PO4 -, CO3, and HCO3 -) and trace metal (Al, Cd, Cu, Fe, and Zn) content. The results show that the pH values range between 6.7 and 8.9, electrical conductivity ranges between 740 and 7340 µS/cm, and nitrate content ranges between 1.7 and 212 mg/l. Hydrochemical facies represented using a Piper diagram indicate an Na-K-Cl type water. All the trace metal concentrations are within the admissible standard range except for Cd. The bacteriological analysis showed that the majority of groundwater samples are contaminated. Generally, the content of total coliforms, fecal coliforms, and fecal streptococci ranged from 0 to 140, 0 to 125, and 0 to 108 CFU/100 ml, respectively. The samples are grouped according to three factors. Factor 1 shows strong positive loadings of EC, Mg, Cl, Na and K with 51.91% of total variance (TV); factor 2 shows strong negative loadings of NO3, SO4 and Ca with 17.98% of TV; and factor 3 shows strong negative loading of HCO3 with 15.56 of TV. We conclude that the quality of this groundwater is suitable for irrigation and domestic use (cleaning house, ect).
Time vs. Money: A Quantitative Evaluation of Monitoring Frequency vs. Monitoring Duration.
McHugh, Thomas E; Kulkarni, Poonam R; Newell, Charles J
2016-09-01
The National Research Council has estimated that over 126,000 contaminated groundwater sites are unlikely to achieve low ug/L clean-up goals in the foreseeable future. At these sites, cost-effective, long-term monitoring schemes are needed in order to understand the long-term changes in contaminant concentrations. Current monitoring optimization schemes rely on site-specific evaluations to optimize groundwater monitoring frequency. However, when using linear regression to estimate the long-term zero-order or first-order contaminant attenuation rate, the effect of monitoring frequency and monitoring duration on the accuracy and confidence for the estimated attenuation rate is not site-specific. For a fixed number of monitoring events, doubling the time between monitoring events (e.g., changing from quarterly monitoring to semi-annual monitoring) will double the accuracy of estimated attenuation rate. For a fixed monitoring frequency (e.g., semi-annual monitoring), increasing the number of monitoring events by 60% will double the accuracy of the estimated attenuation rate. Combining these two factors, doubling the time between monitoring events (e.g., quarterly monitoring to semi-annual monitoring) while decreasing the total number of monitoring events by 38% will result in no change in the accuracy of the estimated attenuation rate. However, the time required to collect this dataset will increase by 25%. Understanding that the trade-off between monitoring frequency and monitoring duration is not site-specific should simplify the process of optimizing groundwater monitoring frequency at contaminated groundwater sites. © 2016 The Authors. Groundwater published by Wiley Periodicals, Inc. on behalf of National Ground Water Association.
GRACE-FO Satellites in a Clean Room at Vandenberg Air Force Base
2018-03-12
One of the two Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) satellites and its turntable fixture at the Astrotech Space Operations processing facility at Vandenberg Air Force Base, California. GRACE-FO will extend GRACE's legacy of scientific achievements, which range from tracking mass changes of Earth's polar ice sheets and estimating global groundwater changes, to measuring the mass changes of large earthquakes and inferring changes in deep ocean currents, a driving force in climate. To date, GRACE observations have been used in more than 4,300 research publications. Its measurements provide a unique view of the Earth system and have far-reaching benefits to society, such as providing insights into where global groundwater resources may be shrinking or growing and where dry soils are contributing to drought. GRACE-FO is planned to fly at least five years. https://photojournal.jpl.nasa.gov/catalog/PIA22339
GRACE-FO Satellites in a Clean Room at Vandenberg Air Force Base
2018-03-12
The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) twin satellites, attached to turntable fixtures, at the Astrotech Space Operations processing facility at Vandenberg Air Force Base, California. GRACE-FO will extend GRACE's legacy of scientific achievements, which range from tracking mass changes of Earth's polar ice sheets and estimating global groundwater changes, to measuring the mass changes of large earthquakes and inferring changes in deep ocean currents, a driving force in climate. To date, GRACE observations have been used in more than 4,300 research publications. Its measurements provide a unique view of the Earth system and have far-reaching benefits to society, such as providing insights into where global groundwater resources may be shrinking or growing and where dry soils are contributing to drought. GRACE-FO is planned to fly at least five years. https://photojournal.jpl.nasa.gov/catalog/PIA22341
GRACE-FO Satellites in a Clean Room at Vandenberg Air Force Base
2018-03-12
The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) twin satellites, attached to turntable fixtures, at the Astrotech Space Operations processing facility at Vandenberg Air Force Base, California. GRACE-FO will extend GRACE's legacy of scientific achievements, which range from tracking mass changes of Earth's polar ice sheets and estimating global groundwater changes, to measuring the mass changes of large earthquakes and inferring changes in deep ocean currents, a driving force in climate. To date, GRACE observations have been used in more than 4,300 research publications. Its measurements provide a unique view of the Earth system and have far-reaching benefits to society, such as providing insights into where global groundwater resources may be shrinking or growing and where dry soils are contributing to drought. GRACE-FO is planned to fly at least five years. https://photojournal.jpl.nasa.gov/catalog/PIA22338
GRACE-FO Satellites in a Clean Room at Vandenberg Air Force Base
2018-03-12
The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) twin satellites, attached to turntable fixtures, at the Astrotech Space Operations processing facility at Vandenberg Air Force Base, California. GRACE-FO will extend GRACE's legacy of scientific achievements, which range from tracking mass changes of Earth's polar ice sheets and estimating global groundwater changes, to measuring the mass changes of large earthquakes and inferring changes in deep ocean currents, a driving force in climate. To date, GRACE observations have been used in more than 4,300 research publications. Its measurements provide a unique view of the Earth system and have far-reaching benefits to society, such as providing insights into where global groundwater resources may be shrinking or growing and where dry soils are contributing to drought. GRACE-FO is planned to fly at least five years. https://photojournal.jpl.nasa.gov/catalog/PIA22340
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1994-09-06
The Muskego Sanitary Landfill site is situated within the City of Muskego, Waukesha County, in the State of Wisconsin. Muskego Sanitary Landfill is a former sand and gravel pit which received unspecified types and amounts of municipal and industrial wastes over a period of approximately 25 years. Muskego Sanitary Landfill site is a public health hazard because in the past some nearby residents probably drank private well water containing site-related contamination. The groundwater around the site might pose a future public health hazard if no further action were taken to clean up the site. Ambient air near Muskego Sanitary Landfillmore » is an indeterminate public health hazard. Wisconsin's Department of Health and Social Services, Division of Health (DOH) recommends the continued monitoring of groundwater in the vicinity of the site.« less
Groundwater cleanup demonstrations at Complex 34, CCAS
NASA Technical Reports Server (NTRS)
2000-01-01
At Launch Complex 34, Cape Canaveral Air Station, several studies are under way for groundwater cleanup of trichloroethylene at the site. Shown here is monitoring equipment for one of the methods, potassium permanganate oxidation. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program in the 60s. The environmental research project involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA, who formed the Interagency NDAPL Consortium (IDC), to study three contamination cleanup technologies: Six Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. KSC hosted a two-day conference that presented information and demonstrations of the three technologies for representatives from environmental and federal agencies.
D-Area Drip Irrigation-Phytoremediation Project: SRTC Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilde, E.W.
2003-01-14
Groundwater in D-Area at the Savannah River Site (SRS) is contaminated with trichloroethylene (TCE) and by-products resulting from discharges of this organic solvent during past operations. Several potential clean-up strategies are being or have been investigated, including a novel drip irrigation-phytoremediation process that is the focus of the treatability study described in this report. The contaminated groundwater in D-Area occurs primarily at depths of 30 to 50 feet below ground surface, well below the depths that are typically penetrated by plant roots. The system investigated in this study involved pumping water from the contaminated aquifer and discharging the water intomore » overlying test plots below the surface using drip irrigation. The test plots contained pines, cottonwoods, or no vegetation (controls). The primary objective was to determine the overall effectiveness of the process for TCE removal and to elucidate the biotic and abiotic pathways for its removal.« less
Energy Transitions | Integrated Energy Solutions | NREL
clean energy access to remote populations across West Africa. NREL Supports Effort to Take Distributed develops and implements pilot projects to accelerate the development of distributed photovoltaics Renewable Energy into India's Electric Grid Volume 1 Volume 2 Designing Distributed Generation in Mexico
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solutions to improve the energy efficiency of both residential and commercial buildings, and to accelerate the integration of clean energy technologies with buildings. NREL's commercial buildings research focuses on providing large institutional and private sector commercial building owners with tools
Contribution of the backstreaming ions to the self-magnetic pinch (SMP) diode current
NASA Astrophysics Data System (ADS)
Mazarakis, Michael G.; Bennett, Nichelle; Cuneo, Michael E.; Fournier, Sean D.; Johnston, Mark D.; Kiefer, Mark L.; Leckbee, Joshua J.; Nielsen, Dan S.; Oliver, Bryan V.; Sceiford, Matthew E.; Simpson, Sean C.; Renk, Timothy J.; Ruiz, Carlos L.; Webb, Timothy J.; Ziska, Derek; Droemer, Darryl W.; Gignac, Raymond E.; Obregon, Robert J.; Wilkins, Frank L.; Welch, Dale R.
2018-04-01
The results presented here were obtained with a self-magnetic pinch (SMP) diode mounted at the front high voltage end of the RITS accelerator. RITS is a Self-Magnetically Insulated Transmission Line (MITL) voltage adder that adds the voltage pulse of six 1.3 MV inductively insulated cavities. The RITS driver together with the SMP diode has produced x-ray spots of the order of 1 mm in diameter and doses adequate for the radiographic imaging of high area density objects. Although, through the years, a number of different types of radiographic electron diodes have been utilized with SABER, HERMES III and RITS accelerators, the SMP diode appears to be the most successful and simplest diode for the radiographic investigation of various objects. Our experiments had two objectives: first to measure the contribution of the back-streaming ion currents emitted from the anode target and second to try to evaluate the energy of those ions and hence the Anode-Cathode (A-K) gap actual voltage. In any very high voltage inductive voltage adder utilizing MITLs to transmit the power to the diode load, the precise knowledge of the accelerating voltage applied on the A-K gap is problematic. This is even more difficult in an SMP diode where the A-K gap is very small (˜1 cm) and the diode region very hostile. The accelerating voltage quoted in the literature is from estimates based on the measurements of the anode and cathode currents of the MITL far upstream from the diode and utilizing the para-potential flow theories and inductive corrections. Thus, it would be interesting to have another independent measurement to evaluate the A-K voltage. The diode's anode is made of a number of high-Z metals in order to produce copious and energetic flash x-rays. It was established experimentally that the back-streaming ion currents are a strong function of the anode materials and their stage of cleanness. We have measured the back-streaming ion currents emitted from the anode and propagating through a hollow cathode tip for various diode configurations and different techniques of target cleaning treatment: namely, heating at very high temperatures with DC and pulsed current, with RF plasma cleaning, and with both plasma cleaning and heating. We have also evaluated the A-K gap voltage by energy filtering technique. Experimental results in comparison with LSP simulations are presented.
Tang, Yulu; Zhong, Bifeng; Qu, Bing; Feng, Shujin; Ding, Sanglan; Su, Shijun; Li, Zhi; Gan, Zhiwei
2017-05-24
A total of 28 groundwater, paired farmland soil, lettuce, and its rhizosphere soil samples were collected from Chengdu, China to detect perchlorate levels and to evaluate the relationships of perchlorate concentrations among these matrices. The perchlorate concentrations in the groundwater, farmland soil, lettuce, and rhizosphere soil samples ranged from below detection limit to 60.2 μg L -1 , from below detection limit to 249 μg kg -1 dry weight (dw), from 2.07 to 1010 μg kg -1 wet weight, and from below detection limit to 314 μg kg -1 dw, respectively. Significant correlation was found in the perchlorate levels among the farmland soil, lettuce, and rhizosphere soil, suggesting that they have common pollution sources, or perchlorate might transfer from farmland soil-rhizosphere soil-plant. However, there is no significant correlation between groundwater and the other three matrices, indicating that infiltration from perchlorate contaminated farmland soil was not the predominant source for groundwater pollution in Chengdu. The perchlorate concentrations in the farmland soil and lettuce samples were significantly higher than those in the rhizosphere soil, primarily due to uptake of perchlorate through the rhizosphere micro-environment by lettuce, or accelerated degradation by rhizospheric microorganisms, which contributed more needs further investigation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Firestone, Mary
Objectives of proposed research were to; Determine if the trajectories of microbial community composition and function following organic carbon amendment can be related to, and predicted by, key environmental determinants; Assess the relative importance of the characteristics of the indigenous microbial community, sediment, groundwater, and concentration of organic carbon amendment as the major determinants of microbial community functional response and bioremediation capacity; and Provide a fundamental understanding of the microbial community ecology underlying subsurface metal remediation requisite to successful application of accelerated remediation and long-term stewardship of DOE-IFC sites.
Integrating hydrology into catchment scale studies - need for new paradigms?
NASA Astrophysics Data System (ADS)
Teutsch, G.
2009-04-01
Until the seventies, scientific development in the field of groundwater hydrology concentrated mainly on a better understanding of the physics of subsurface flow in homogeneous or simply stratified porous respectively fractured media. Then, since mid of the seventies, a much more complex vision of groundwater hydrology gradually developed. A more realistic description of the subsurface including its heterogeneity, predominant physico-chemical-biological reactions and also technologies for the efficient clean-up of contaminants developed during the past 30 years, much facilitated by the advancement in numerical modelling techniques and the boost in computer power. Even though the advancements in this field have been very significant, a new grand challenge evolved during the past 10 years trying to bring together the fields needed to build Integrated Watershed Management Systems (IWMS). The fundamental conceptual question is: Do we need new approaches to groundwater hydrology, maybe even new paradigms in order to successfully build IWMS - or can we simply extrapolate our existing concepts and tool-sets to the scale of catchments and watersheds and simply add some interfaces to adjacent disciplines like economy, ecology and others? This lecture tries to provide some of the answers by describing some successful examples.
Key NASA, USAF and federal officials sign a Memorandum of Agreement on groundwater cleanup
NASA Technical Reports Server (NTRS)
1999-01-01
On the site of Launch Complex 34, key participants sign a Memorandum of Agreement, formalizing cooperative efforts of NASA, the U.S. Air Force, and federal agencies in ground-water cleanup initiatives. Seated at the table, from left to right, are Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; Roy Bridges Jr., director of John F. Kennedy Space Center; Walter Kovalick Jr., Ph.D., director, Technology Innovation Office, U.S. Environmental Protection Agency. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally.
Key NASA, USAF and federal officials sign a Memorandum of Agreement on groundwater cleanup
NASA Technical Reports Server (NTRS)
1999-01-01
On the site of Launch Complex 34, key participants sign a Memorandum of Agreement, formalizing cooperative efforts of NASA, the U.S. Air Force, and federal agencies in ground-water cleanup initiatives. Seated from left to right are Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; Roy Bridges Jr., director of John F. Kennedy Space Center; Walter Kovalick Jr., Ph.D., director, Technology Innovation Office, U.S. Environmental Protection Agency. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally.
NASA Astrophysics Data System (ADS)
Ng, G. H. C.; Wickert, A. D.; McLaughlin, R.; La Frenierre, J.; Liess, S.; Saberi, L.
2016-12-01
Climate change projections show greater rates at higher elevations, making tropical glaciated regions some of the most vulnerable hydrological systems and the earliest windows into changing conditions in mountainous watersheds. Many of the subsistence agrarian communities below Volcán Chimborazo, Ecuador, experience water stress, heightening the urgency to understand the hydrological impacts of climate change. Previous hydrochemical and physical observations suggest that a significant fraction of glacial melt may first recharge underlying groundwater before discharging to streams at lower elevations. This has important implications for tracking hydrological response to climate change, due to differences in the spatiotemporal behavior of surface water vs. groundwater. However, differentiating meltwater-sourced and precipitation-sourced groundwater throughout the watershed poses a challenge in elucidating the influence of accelerated but finite glacial melt on streamflow. In addition to glacial melt, recently noted upslope vegetation migration on Chimborazo will likely complicate future predictions of water availability by influencing the relative amounts of groundwater sources and changing discharge through altered evapotranspiration along riparian zones. To investigate the roles of groundwater pathways and vegetation on glacial melt contributions to streamflow, we implement the coupled groundwater/rainfall-runoff model GSFLOW. We infer hydrogeological model inputs from geological maps of Chimborazo and vegetation properties from a combination of remotely sensed imagery and in-situ surveys. Dynamically downscaled meteorological state variables, checked against field data, force the model. Such a model enables the quantification of the current meltwater contribution to streamflow at critical water extraction points and allows us to probe potential meltwater and water resource changes under future climate change scenarios.
Yu, Kai; Gan, Yiqun; Zhou, Aiguo; Liu, Chongxuan; Duan, Yanhua; Han, Li; Zhang, Yanan
2018-05-30
Groundwater arsenic contamination is a common environmental problem that threatens the health of over 100 million people globally. Apparent seasonal fluctuations in groundwater arsenic concentrations have been reported in various locations worldwide, including the Jianghan Plain, central China. This phenomenon has been attributed to shifts in redox conditions induced by seasonal incursions of surface water. However, it is not clear what processes during the incursion lead to changes in the redox conditions and what is the source of the organic carbon driving these processes. Therefore, we conducted a long-term investigation of stable carbon isotopic compositions in surface water and groundwater, as well as long-term monitoring of hydraulic gradients and geochemical compositions at the Jianghan Plain. Results indicated that a series of biogeochemical processes occurred during surface water incursion, including aerobic microbial respiration, nitrate and sulfate reduction. Groundwater arsenic was removed by adsorption on iron oxyhydroxides produced during oxidation of ferrous iron, resulting in dramatic decreases in arsenic concentrations during surface water recharge seasons. These processes were likely driven by organic carbon vertically transported from surface water and released from the surficial aquitard above 15 m. Groundwater pumping may accelerate the vertical infiltration of oxidizing recharge water and drive exogenous organic carbon to depth. Findings of this study advance the understandings of the mechanisms that cause temporal variations in groundwater As and the importance of exogenous organic carbon that may influence the temporal behavior of arsenic in groundwater. Copyright © 2018 Elsevier Ltd. All rights reserved.
RESTORING HAZARDOUS SPILL-DAMAGED AREAS: TECHNIQUE IDENTIFICATION/ASSESSMENT
The goal of this study was to identify and assess methods that could be used to accelerate the restoration of lands damaged by spills of hazardous materials. The literature was reviewed to determine what response methods had been used in the past to clean up spills on land and id...
physicist invents new way to clean up oil spills Fermilab physicist Arden Warner revolutionizes oil spill cleanup with magnetizable-oil invention. Photo: Hanae Armitage Four years ago, Fermilab accelerator physicist Arden Warner watched national news of the BP oil spill and found himself frustrated with the
Towards plasma cleaning of ITER first mirrors
NASA Astrophysics Data System (ADS)
Moser, L.; Marot, L.; Eren, B.; Steiner, R.; Mathys, D.; Leipold, F.; Reichle, R.; Meyer, E.
2015-06-01
To avoid reflectivity losses in ITER's optical diagnostic systems, on-site cleaning of metallic first mirrors via plasma sputtering is foreseen to remove deposit build-ups migrating from the main wall. In this work, the influence of aluminium and tungsten deposits on the reflectivity of molybdenum mirrors as well as the possibility to clean them with plasma exposure is investigated. Porous ITER-like deposits are grown to mimic the edge conditions expected in ITER, and a severe degradation in the specular reflectivity is observed as these deposits build up on the mirror surface. In addition, dense oxide films are produced for comparisons with porous films. The composition, morphology and crystal structure of several films were characterized by means of scanning electron microscopy, x-ray photoelectron spectroscopy, x-ray diffraction and secondary ion mass spectrometry. The cleaning of the deposits and the restoration of the mirrors' optical properties are possible either with a Kaufman source or radio frequency directly applied to the mirror (or radio frequency plasma generated directly around the mirror surface). Accelerating ions of an external plasma source through a direct current applied onto the mirror does not remove deposits composed of oxides. A possible implementation of plasma cleaning in ITER is addressed.
Balanced Rotating Spray Tank and Pipe Cleaning and Cleanliness Verification System
NASA Technical Reports Server (NTRS)
Caimi, Raoul E. B. (Inventor); Thaxton, Eric A. (Inventor)
1998-01-01
A system for cleaning and verifying the cleanliness of the interior surfaces of hollow items, such as small bottles, tanks, pipes and tubes, employs a rotating spray head for supplying a gas-liquid cleaning mixture to the item's surface at a supersonic velocity. The spray head incorporates a plurality of nozzles having diverging cross sections so that the incoming gas-liquid mixture is first converged within the spray head and then diverged through the nozzles, thereby accelerating the mixture to a supersonic velocity. In the preferred embodiment, three nozzles are employed; one forwardly facing nozzle at the end of the spray head and two oppositely facing angled nozzles exiting on opposite sides of the spray head which balance each other, and therefore impart no net side load on the spray head. A drive mechanism is provided to rotate the spray head and at the same time move the head back and forth within the item to be cleaned. The drive mechanism acts on a long metal tube to which the spray head is fixed, and thus no moving parts are exposed to the interior surfaces of the items to be cleaned, thereby reducing the risk of contamination.
Genesis of hexavalent chromium from natural sources in soil and groundwater.
Oze, Christopher; Bird, Dennis K; Fendorf, Scott
2007-04-17
Naturally occurring Cr(VI) has recently been reported in ground and surface waters. Rock strata rich in Cr(III)-bearing minerals, in particular chromite, are universally found in these areas that occur near convergent plate margins. Here we report experiments demonstrating accelerated dissolution of chromite and subsequent oxidation of Cr(III) to aqueous Cr(VI) in the presence of birnessite, a common manganese mineral, explaining the generation of Cr(VI) by a Cr(III)-bearing mineral considered geochemically inert. Our results demonstrate that Cr(III) within ultramafic- and serpentinite-derived soils/sediments can be oxidized and dissolved through natural processes, leading to hazardous levels of aqueous Cr(VI) in surface and groundwater.
Genesis of hexavalent chromium from natural sources in soil and groundwater
Oze, Christopher; Bird, Dennis K.; Fendorf, Scott
2007-01-01
Naturally occurring Cr(VI) has recently been reported in ground and surface waters. Rock strata rich in Cr(III)-bearing minerals, in particular chromite, are universally found in these areas that occur near convergent plate margins. Here we report experiments demonstrating accelerated dissolution of chromite and subsequent oxidation of Cr(III) to aqueous Cr(VI) in the presence of birnessite, a common manganese mineral, explaining the generation of Cr(VI) by a Cr(III)-bearing mineral considered geochemically inert. Our results demonstrate that Cr(III) within ultramafic- and serpentinite-derived soils/sediments can be oxidized and dissolved through natural processes, leading to hazardous levels of aqueous Cr(VI) in surface and groundwater. PMID:17420454
NASA Astrophysics Data System (ADS)
Kemah, Elif; Akkaya, Recep; Tokgöz, Seyit Rıza
2017-02-01
In recent years, the accelerator driven subcritical reactors have taken great interest worldwide. The Accelerator Driven System (ADS) has been used to produce neutron in subcritical state by the external proton beam source. These reactors, which are hybrid systems, are important in production of clean and safe energy and conversion of radioactive waste. The ADS with the selection of reliability and robust target materials have been the new generation of fission reactors. In addition, in the ADS Reactors the problems of long-lived radioactive fission products and waste actinides encountered in the fission process of the reactor during incineration can be solved, and ADS has come to the forefront of thorium as fuel for the reactors.
NASA Astrophysics Data System (ADS)
Longmire, P.; Dale, M.; Granzow, K.; Yanicak, S. M.
2014-12-01
Los Alamos National Laboratory (LANL) is an operating nuclear site that has released treated effluents from three plutonium-processing facilities since the mid 1940s. The radioisotope 129I (T1/2 = 15.7 Myrs) derived from235U and 239Pu processing at LANL is locally detected in groundwater above background concentrations. This isotope provides a unique tracer for groundwater investigations conducted at LANL that helps to identify source releases linked to groundwater-flow paths in aquifers subject to binary and ternary mixing of natural- and industrial-derived waters containing chromate and other chemicals. Bromide, chlorate, chloride, nitrate, perchlorate, sulfate, and tritium were associated with multiple outfalls at LANL and, therefore, do not provide unique chemical signatures identifying a specific point of release or source. Natural and anthropogenic ratios of 129I/127I measured in groundwater samples collected at LANL were quantified using accelerator mass spectrometry at Purdue Rare Isotope Measurement Laboratory, Purdue University. Anthropogenic ratios of 129I/127I range from 1,531 X 10-15 to 10,323 X 10-15 within perched-intermediate groundwater present in volcanoclastic and basalt aquifers (210 - 216 m depth). Anthropogenic ratios of 129I/127I range from 359 X 10-15 to 4,350 X 10-15 within the regional aquifer (280 m depth) consisting of volcanoclastic sediments of variable hydraulic properties. Local background ratios of 129I/127I have a narrow range of 171 X 10-15 to 378 X 10-15 in the regional aquifer. Dissolved iodide measured in groundwater at LANL is stable dominantly as iodate. Background concentrations of dissolved iodate (0.1 to 33.2 nM) are less variable compared to anthropogenic iodate (8.0 to 246 nM) in groundwater at the site. Variability in concentrations of anthropogenic iodate is controlled by heterogeneous source releases of iodate over time and non-uniform mixing of groundwater in the different aquifers.
NASA Astrophysics Data System (ADS)
Glas, R. L.; Lautz, L.; McKenzie, J. M.; Baker, E. A.; Somers, L. D.; Aubry-Wake, C.; Wigmore, O.; Mark, B. G.; Moucha, R.
2016-12-01
Groundwater- surface water interactions in alpine catchments are often poorly understood as groundwater and hydrologic data are difficult to acquire in these remote areas. The Cordillera Blanca of Peru is a region where dry-season water supply is increasingly stressed due to the accelerated melting of glaciers throughout the range, affecting millions of people country-wide. The alpine valleys of the Cordillera Blanca have shown potential for significant groundwater storage and discharge to valley streams, which could buffer the dry-season variability of streamflow throughout the watershed as glaciers continue to recede. Known as pampas, the clay-rich, low-relief valley bottoms are interfingered with talus deposits, providing a likely pathway for groundwater recharged at the valley edges to be stored and slowly released to the stream throughout the year by springs. Multiple geophysical methods were used to determine areas of groundwater recharge and discharge as well as aquifer geometry of the pampa system. Seismic refraction tomography, vertical electrical sounding (VES), electrical resistivity tomography (ERT), and horizontal-to-vertical spectral ratio (HVSR) seismic methods were used to determine the physical properties of the unconsolidated valley sediments, the depth to saturation, and the depth to bedrock for a representative section of the Quilcayhuanca Valley in the Cordillera Blanca. Depth to saturation and lithological boundaries were constrained by comparing geophysical results to continuous records of water levels and sediment core logs from a network of seven piezometers installed to depths of up to 6 m. Preliminary results show an average depth to bedrock for the study area of 25 m, which varies spatially along with water table depths across the valley. The conceptual model of groundwater flow and storage derived from these geophysical data will be used to inform future groundwater flow models of the area, allowing for the prediction of groundwater resources for the region in the absence of glacial meltwater.
Groundwater: the processes and global significance of aquifer degradation.
Foster, S S D; Chilton, P J
2003-01-01
The exploitation of groundwater resources for human use dates from the earliest civilizations, but massive resource development has been largely restricted to the past 50 years. Although global in scope, the emphasis of this paper is on groundwater-based economies in a developing nation context, where accelerated resource development has brought major social and economic benefits over the past 20 years. This results from groundwater's significant role in urban water supply and in rural livelihoods, including irrigated agriculture. However, little of the economic benefit of resource development has been reinvested in groundwater management, and concerns about aquifer degradation and resource sustainability began to arise. A general review, for a broad-based audience, is given of the mechanisms and significance of three semi-independent facets of aquifer degradation. These are (i) depletion of aquifer storage and its effects on groundwater availability, terrestrial and aquatic ecosystems; (ii) groundwater salinization arising from various different processes of induced hydraulic disturbance and soil fractionation; and (iii) vulnerability of aquifers to pollution from land-use and effluent discharge practices related to both urban development and agricultural intensification. Globally, data with which to assess the status of aquifer degradation are of questionable reliability, inadequate coverage and poor compilation. Recourse has to be made to 'type examples' and assumptions about the extension of similar hydrogeological settings likely to be experiencing similar conditions of groundwater demand and subsurface contaminant load. It is concluded that (i) aquifer degradation is much more than a localized problem because the sustainability of the resource base for much of the rapid socio-economic development of the second half of the twentieth century is threatened on quite a widespread geographical basis; and (ii) major (and long overdue) investments in groundwater resource and quality protection are urgently needed. These investments include appropriate institutional provisions, demand-side management, supply-side enhancement and pollution control. PMID:14728791
NASA Astrophysics Data System (ADS)
Feng, Dapeng; Zheng, Yi; Mao, Yixin; Zhang, Aijing; Wu, Bin; Li, Jinguo; Tian, Yong; Wu, Xin
2018-02-01
Water resources in coastal areas can be profoundly influenced by both climate change and human activities. These climatic and human impacts are usually intertwined and difficult to isolate. This study developed an integrated model-based approach for detection and attribution of climatic and human impacts and applied this approach to the Luanhe Plain, a typical coastal area in northern China. An integrated surface water-groundwater model was developed for the study area using GSFLOW (coupled groundwater and surface-water flow). Model calibration and validation were performed for background years between 1975 and 2000. The variation in water resources between the 1980s and 1990s was then quantitatively attributed to climate variability, groundwater pumping and changes in upstream inflow. Climate scenarios for future years (2075-2100) were also developed by downscaling the projections in CMIP5. Potential water resource responses to climate change, as well as their uncertainty, were then investigated through integrated modeling. The study results demonstrated the feasibility and value of the integrated modeling-based analysis for water resource management in areas with complex surface water-groundwater interaction. Specific findings for the Luanhe Plain included the following: (1) During the historical period, upstream inflow had the most significant impact on river outflow to the sea, followed by climate variability, whereas groundwater pumping was the least influential. (2) The increase in groundwater pumping had a dominant influence on the decline in groundwater change, followed by climate variability. (3) Synergetic and counteractive effects among different impacting factors, while identified, were not significant, which implied that the interaction among different factors was not very strong in this case. (4) It is highly probable that future climate change will accelerate groundwater depletion in the study area, implying that strict regulations for groundwater pumping are imperative for adaptation.
Role of Climatic Variability on Fate and Transport of LNAPL Pollutants in Subsurface
NASA Astrophysics Data System (ADS)
Gupta, P. K.; Yadav, B. K.
2017-12-01
Climatic variability affects groundwater resources both directly through replenishment by surface recharge and indirectly via changes in groundwater extraction patterns. Remediation of polluted groundwater due to the release of mono-aromatic hydrocarbons such as light non-aqueous phase liquids (LNAPL) is of particular concern under changing climatic conditions because of their higher water solubility and wide coverage in the subsurface. Thus, the aim of this study was to investigate the impact of these shallow groundwater extremes on biodegradation and transport of toluene, the selected LNAPL, in subsurface using a series of practical and numerical experiments. An air tight three-dimensional sand tank setup (60cm-L×30cm-W×60cm-D) embedded with horizontal and vertical layers of sampling ports was fabricated using a glass sheet of thickness 7 mm. Clean sand having an average grain size of 0.5-1.0 mm was packed homogeneously for creating an unconfined aquifer. Pure phase of toluene was released from the top surface to create a pool of the LNAPL around the groundwater table which was maintained at 35 cm from the tank bottom. Initially, a constant water flux was allowed to flow to maintain a pore water velocity of 1.2 m/day in lateral direction to mimic a base groundwater flow regime. Subsequently, faster and slow groundwater velocity regimes were developed by changing the water flux through the saturated zone keeping the water table location at the same level. The observed breakthrough curves at different ports showed that lateral and transverse transport of the LNAPL was more prominent as compared to its vertical movement. The increased vertical movement of the LNAPL along with an enhanced dissolution rate under the faster groundwater flow condition shows the crucial role of mechanical dispersion and the shear force acting on the water-LNAPL interface. The rate of degradation was found high for the case of faster pore water velocities due to dependency of the degradation kinetics on substrate concentration. The observed data were compared well with the simulated curves for all the three cases of groundwater flow conditions. The results of this study are of direct use in applying bioremediation technique in the field and for planning of LNAPL polluting industrial locations under changing climatic conditions.
Land Use, Climate, and Water Resources-Global Stages of Interaction.
Kaushal, Sujay S; Gold, Arthur J; Mayer, Paul M
2017-10-24
Land use and climate change can accelerate the depletion of freshwater resources that support humans and ecosystem services on a global scale. Here, we briefly review studies from around the world, and highlight those in this special issue. We identify stages that characterize increasing interaction between land use and climate change. During the first stage, hydrologic modifications and the built environment amplify overland flow via processes associated with runoff-dominated ecosystems (e.g., soil compaction, impervious surface cover, drainage, and channelization). During the second stage, changes in water storage impact the capacity of ecosystems to buffer extremes in water quantity and quality (e.g., either losses in snowpack, wetlands, and groundwater recharge or gains in water and nutrient storage behind dams in reservoirs). During the third stage, extremes in water quantity and quality contribute to losses in ecosystem services and water security (e.g., clean drinking water, flood mitigation, and habitat availability). During the final stage, management and restoration strategies attempt to regain lost ecosystem structure, function, and services but need to adapt to climate change. By anticipating the increasing interaction between land use and climate change, intervention points can be identified, and management strategies can be adjusted to improve outcomes for realistic expectations. Overall, global water security cannot be adequately restored without considering an increasing interaction between land use and climate change across progressive stages and our ever-increasing human domination of the water cycle from degradation to ecosystem restoration.
Natural Remediation at Savannah River Site
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lewis, C. M.; Van Pelt, R.
2002-02-25
Natural remediation is a general term that includes any technology or strategy that takes advantage of natural processes to remediate a contaminated media to a condition that is protective of human health and the environment. Natural remediation techniques are often passive and minimally disruptive to the environment. They are generally implemented in conjunction with traditional remedial solutions for source control (i.e., capping, stabilization, removal, soil vapor extraction, etc.). Natural remediation techniques being employed at Savannah River Site (SRS) include enhanced bio-remediation, monitored natural attenuation, and phytoremediation. Enhanced bio-remediation involves making nutrients available and conditions favorable for microbial growth. With propermore » precautions and feeding, the naturally existing microbes flourish and consume the contaminants. Case studies of enhanced bio-remediation include surface soils contaminated with PCBs and pesticides, and Volatile Organic Compound (VOC) contamination in both the vadose zone and groundwater. Monitored natural attenuation (MNA) has been selected as the preferred alternative for groundwater clean up at several SRS waste units. Successful implementation of MNA has been based on demonstration that sources have been controlled, groundwater modeling that indicates that plumes will not expand or reach surface water discharge points at levels that exceed regulatory limits, and continued monitoring. Phytoremediation is being successfully utilized at several SRS waste units. Phytoremediation involves using plants and vegetation to uptake, break down, or manage contaminants in groundwater or soils. Case studies at SRS include managing groundwater plumes of tritium and VOCs with pine trees that are native to the area. Significant decreases in tritium discharge to a site stream have been realized in one phytoremediation project. Studies of other vegetation types, methods of application, and other target contaminants are underway.« less
Impact of heterogeneity on groundwater salinization due to coastal pumping
NASA Astrophysics Data System (ADS)
Yu, X.; Michael, H. A.
2017-12-01
Groundwater abstraction causes and accelerates seawater intrusion in many coastal areas. In heterogeneous aquifers, preferential flow paths can lead to fast intrusion, while low permeability layers can serve as barriers. The extent to which different types of heterogeneous aquifers are vulnerable to pumping-induced seawater intrusion has not been well studied. Here we show that the connectedness of pumping location and local boundary condition drive salinization patterns. Salinization patterns in homogeneous aquifers were relatively simple and only related to the hydraulic properties and pumping rate. The salinization rates and patterns in heterogeneous aquifers were much more complicated and related to pumping location, rate and depth, preferential flow path locations, and local boundary conditions. An intrusion classification approach was developed with three types in homogeneous aquifers and four types in heterogeneous aquifers. After classification the main factors of salinized areas, intrusion rates and salinization time could be identified. The ranges of these salinization assessment criteria suggested different aspect of groundwater vulnerability in each class. We anticipate the classification approach to be a starting point for more comprehensive groundwater abstraction vulnerability assessment (including consideration of pumping rates, locations and depths, connectivity, preferential flow paths, etc.), which is critical for coastal water resources management.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dorr, Kent A.; Ostrom, Michael J.; Freeman-Pollard, Jhivaun R.
CH2M Hill Plateau Remediation Company (CHPRC) designed, constructed, commissioned, and began operation of the largest groundwater pump and treatment facility in the U.S. Department of Energy’s (DOE) nationwide complex. This one-of-a-kind groundwater pump and treatment facility, located at the Hanford Nuclear Reservation Site (Hanford Site) in Washington State, was built to an accelerated schedule with American Recovery and Reinvestment Act (ARRA) funds. There were many contractual, technical, configuration management, quality, safety, and Leadership in Energy and Environmental Design (LEED) challenges associated with the design, procurement, construction, and commissioning of this $95 million, 52,000 ft groundwater pump and treatment facility tomore » meet DOE’s mission objective of treating contaminated groundwater at the Hanford Site with a new facility by June 28, 2012. The project team’s successful integration of the project’s core values and green energy technology throughout design, procurement, construction, and start-up of this complex, first-of-its-kind Bio Process facility resulted in successful achievement of DOE’s mission objective, as well as attainment of LEED GOLD certification, which makes this Bio Process facility the first non-administrative building in the DOE Office of Environmental Management complex to earn such an award.« less
NASA Astrophysics Data System (ADS)
Christy, Raicy Mani; Lakshmanan, Elango
2017-07-01
Percolation ponds have become very popular methods of managed aquifer recharge due to their low cost, ease of construction and the participation and assistance of community. The objective of this study is to assess the feasibility of a percolation pond in a saline aquifer, north of Chennai, Tamil Nadu, India, to improve the storage and quality of groundwater. Electrical resistivity and ground penetrating radar methods were used to understand the subsurface conditions of the area. From these investigations, a suitable location was chosen and a percolation pond was constructed. The quality and quantity of groundwater of the nearby area has improved due to the recharge from the pond. This study indicated that a simple excavation without providing support for the slope and paving of the bunds helped to improve the groundwater quality. This method can be easily adoptable by farmers who can have a small pond within their farm to collect and store the rainwater. The cost of water recharged from this pond works out to be about 0.225 Re/l. Cleaning the pond by scrapping the accumulated sediments needs to be done once a year. Due to the small dimension and high saline groundwater, considerable improvement in quality at greater depths could not be achieved. However, ponds of larger size with recharge shafts can directly recharge the aquifer and help to improve the quality of water at greater depths.
Lu, Qiang; Luo, Qi Shi; Li, Hui; Liu, Yong Di; Gu, Ji Dong; Fei Lin, Kuang
2015-01-01
CAHs, as a cleaning solvent, widely contaminated shallow groundwater with the development of manufacturing in China's Yangtze River Delta. This study focused on the distribution of CAHs, and correlations between CAHs and environmental variables in a shallow groundwater in Shanghai, using kriging interpolation and multifactorial analysis. The results showed that the overall CAHs plume area (above DIV) was approximately 9,000 m2 and located in the 2–4 m underground, DNAPL was accumulated at an area of approximately 1,400 m2 and located in the 6-8m sandy silt layer on the top of the muddy silty clay. Heatmap of PPC for CAHs and environmental variables showed that the correlation between “Fe2+” and most CAHs such as “1,1,1-TCA”, “1,1-DCA”, “1,1-DCE” and “%TCA” were significantly positive (p<0.001), but “%CA” and/or “%VC” was not, and “Cl-” was significantly positive correlated with “1,1-DCA” and “1,1-DCE” (p<0.001). The PCA demonstrated that the relative proportions of CAHs in groundwater were mostly controlled by the sources and the natural attenuation. In conclusion, the combination of geographical and chemometrics was helpful to establishing an aerial perspective of CAHs and identifying reasons for the accumulation of toxic dechlorination intermediates, and could become a useful tool for characterizing contaminated sites in general. PMID:26565796
Jadhav, Sachin V; Bringas, Eugenio; Yadav, Ganapati D; Rathod, Virendra K; Ortiz, Inmaculada; Marathe, Kumudini V
2015-10-01
Chronic contamination of groundwaters by both arsenic (As) and fluoride (F) is frequently observed around the world, which has severely affected millions of people. Fluoride and As are introduced into groundwaters by several sources such as water-rock interactions, anthropogenic activities, and groundwater recharge. Coexistence of these pollutants can have adverse effects due to synergistic and/or antagonistic mechanisms leading to uncertain and complicated health effects, including cancer. Many developing countries are beset with the problem of F and As laden waters, with no affordable technologies to provide clean water supply. The technologies available for the simultaneous removal are akin to chemical treatment, adsorption and membrane processes. However, the presence of competing ions such as phosphate, silicate, nitrate, chloride, carbonate, and sulfate affect the removal efficiency. Highly efficient, low-cost and sustainable technology which could be used by rural populations is of utmost importance for simultaneous removal of both pollutants. This can be realized by using readily available low cost materials coupled with proper disposal units. Synthesis of inexpensive and highly selective nanoadsorbents or nanofunctionalized membranes is required along with encapsulation units to isolate the toxicant loaded materials to avoid their re-entry in aquifers. A vast number of reviews have been published periodically on removal of As or F alone. However, there is a dearth of literature on the simultaneous removal of both. This review critically analyzes this important issue and considers strategies for their removal and safe disposal. Copyright © 2015 Elsevier Ltd. All rights reserved.
Scale-by-scale contributions to Lagrangian particle acceleration
NASA Astrophysics Data System (ADS)
Lalescu, Cristian C.; Wilczek, Michael
2017-11-01
Fluctuations on a wide range of scales in both space and time are characteristic of turbulence. Lagrangian particles, advected by the flow, probe these fluctuations along their trajectories. In an effort to isolate the influence of the different scales on Lagrangian statistics, we employ direct numerical simulations (DNS) combined with a filtering approach. Specifically, we study the acceleration statistics of tracers advected in filtered fields to characterize the smallest temporal scales of the flow. Emphasis is put on the acceleration variance as a function of filter scale, along with the scaling properties of the relevant terms of the Navier-Stokes equations. We furthermore discuss scaling ranges for higher-order moments of the tracer acceleration, as well as the influence of the choice of filter on the results. Starting from the Lagrangian tracer acceleration as the short time limit of the Lagrangian velocity increment, we also quantify the influence of filtering on Lagrangian intermittency. Our work complements existing experimental results on intermittency and accelerations of finite-sized, neutrally-buoyant particles: for the passive tracers used in our DNS, feedback effects are neglected such that the spatial averaging effect is cleanly isolated.
Cryogenic Cathode Cooling Techniques for Improved SABRE Extraction Ion Diode Li Beam Generation
NASA Astrophysics Data System (ADS)
Hanson, D. L.; Johnston, R. R.; Cuneo, M. E.; Menge, P. R.; Fowler, W. E.; Armijo, J.; Nielsen, D. S.; Petmecky, D.
1997-11-01
We are developing techniques for cryogenic cooling of the SABRE extraction ion diode cathode that, combined with source cleaning, should improve the purity and brightness of Li beams for ICF light ion fusion. By liquid helium (LHe) cathode cooling, we have been able to maintain A-K gap base pressures in the range of 5 - 7x10-8 Torr for about 45 minutes. These base pressures extend the monolayer formation time for the worst beam contaminants (H2 and water vapor) to 10 - 100 sec or longer, which should allow the accelerator to be fired without significant Li source recontamination. This technique is compatible with He glow discharge cleaning, laser cleaning, and in situ Li deposition. We are also developing techniques for Ti-gettering of H2 and for cryogenic cooling of cathode electrodes to delay cathode plasma expansion.
Anning, David W.
2008-01-01
The U.S. Geological Survey (USGS) recently completed a regional study in the Southwestern United States to characterize dissolved-solids conditions in major water supplies, including important rivers and aquifers. High concentrations of dissolved solids can degrade a water supply's suitability for important uses, such as drinking water or crop irrigation. In an effort to ensure the continued availability of clean surface and groundwater, USGS scientists identified areas where there have been both increasing and decreasing trends in dissolved-solids concentrations.
Larson, S.J.; Capel, P.D.; VanderLoop, A.G.
1996-01-01
Laboratory and quality assurance procedures for the analysis of ground-water samples for herbicides at the Management Systems Evaluation Area near Princeton, Minnesota are described. The target herbicides include atrazine, de-ethylatrazine, de-isopropylatrazine, metribuzin, alachlor, 2,6-diethylaniline, and metolachlor. The analytical techniques used are solid-phase extraction, and analysis by gas chromatography with mass-selective detection. Descriptions of cleaning procedures, preparation of standard solutions, isolation of analytes from water, sample transfer methods, instrumental analysis, and data analysis are included.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paul Donohoo-Vallett
Revolution Now is an annually updated report produced by the Energy Department’s Office of Energy Efficiency and Renewable Energy that documents the accelerated deployment of five clean energy technologies thriving in the U.S. market – wind turbines, solar technologies for both utility-scale and distributed photovoltaic (PV), electric vehicles (EVs) and light-emitting diodes (LEDs).
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2010-04-01
Expanding training opportunities in the weatherization of buildings will accelerate learning and provide a direct path for many Americans to find jobs in the clean energy field. The National Weatherization Training Portal (NWTP), which is now in the final stages of testing, features multi-media, interactive, self-paced training modules.
BACKGROUND: Increased susceptibility of smokers to ambient PM may potentially promote development of COPD and accelerate already present disease. OBJECTIVES: To characterize the acute and subacute lung function response and inflammatory effects of controlled chamber exposure t...
Linking deposit morphology and clogging in subsurface remediation: Final Technical Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mays, David C.
2013-12-11
Groundwater is a crucial resource for water supply, especially in arid and semiarid areas of the United States west of the 100th meridian. Accordingly, remediation of contaminated groundwater is an important application of science and technology, particularly for the U.S. Department of Energy (DOE), which oversees a number of groundwater remediation sites from Cold War era mining. Groundwater remediation is complex, because it depends on identifying, locating, and treating contaminants in the subsurface, where remediation reactions depend on interacting geological, hydrological, geochemical, and microbiological factors. Within this context, permeability is a fundamental concept, because it controls the rates and pathwaysmore » of groundwater flow. Colloid science is intimately related to permeability, because when colloids are present (particles with equivalent diameters between 1 nanometer and 10 micrometers), changes in hydrological or geochemical conditions can trigger a detrimental reduction in permeability called clogging. Accordingly, clogging is a major concern in groundwater remediation. Several lines of evidence suggest that clogging by colloids depends on (1) colloid deposition, and (2) deposit morphology, that is, the structure of colloid deposits, which can be quantified as a fractal dimension. This report describes research, performed under a 2-year, exploratory grant from the DOE’s Subsurface Biogeochemical Research (SBR) program. This research employed a novel laboratory technique to simultaneously measure flow, colloid deposition, deposit morphology, and permeability in a flow cell, and also collected field samples from wells at the DOE’s Old Rifle remediation site. Field results indicate that suspended solids at the Old Rifle site have fractal structures. Laboratory results indicate that clogging is associated with colloid deposits with smaller fractal dimensions, in accordance with previous studies on initially clean granular media. Preliminary modeling has identified the deposit radius of gyration as a candidate variable to account for clogging as a function of (1) colloid accumulation and (2) deposit morphology.« less
NASA Astrophysics Data System (ADS)
Montgomery, S. D.; Mckibben, M. A.
2011-12-01
Tungsten, an emerging contaminant, has no EPA standard for its permissible levels in drinking water. At sites in California, Nevada, and Arizona there may be a correlation between elevated levels of tungsten in drinking water and clusters of childhood acute lymphocytic leukemia (ALL). Developing a better understanding of how tungsten is released from rocks into surface and groundwaters is therefore of growing environmental interest. Knowledge of tungstate ore mineral weathering processes, particularly the rates of dissolution of scheelite (CaWO4) in groundwater, could improve models of how tungsten is released and transported in natural waters. Our research is focusing on experimental determination of the rates and products of tungstate mineral dissolution in synthetic groundwater, as a function of temperature, pH and mineral surface area. The initial rate method is being used to develop rate laws. Batch reactor experiments are conducted within constant temperature circulation baths over a pH range of 2-9. Cleaned scheelite powder with grain diameters of 106-150um is placed between two screens in a sample platform and then placed inside a two liter Teflon vessel filled with synthetic groundwater. Ports on the vessel allow sample extraction, temperature and pH measurement, gas inflow, and water circulation. Aliquots of solution are taken periodically for product analysis by ICP -MS. Changes in mineral surface characteristics are monitored using SEM and EDS methods. Results so far reveal that the dissolution of scheelite is incongruent at both neutral and low pH. Solid tungstic acid forms on scheelite mineral surfaces under acidic conditions, implying that this phase controls the dissolution rate in acidic environments. The influence of dissolved CO2 and resultant calcium carbonate precipitation on the dissolution of scheelite at higher pH is also being investigated. The rate law being developed for scheelite dissolution will be useful in reactive-transport computer codes designed to model tungsten contamination in a variety of surface and groundwater settings.
An Assessment of Peri-Urban Groundwater Quality from Shallow Dug Wells, Mzuzu, Malawi
NASA Astrophysics Data System (ADS)
Holm, R.; Felsot, A.
2012-12-01
Throughout Malawi, governmental, non-governmental, religious and civic organizations are targeting the human need for water. Diarrheal diseases, often associated with unsafe drinking water, are a leading cause of mortality in children under five in Malawi with over 6,000 deaths per year (World Health Organization, 2010). From January to March 2012, a field study was undertaken in Malawi to study water quality and develop a public health risk communication strategy. The region studied, Area 1B, represents a comparatively new peri-urban area on the edge of Mzuzu city. Area 1B is serviced by a piped municipal water supply, but many shallow dug wells are also used for household water. Groundwater samples were collected from 30 shallow dug well sites and analyzed for nitrate, total coliform, Escherichia coli, total hardness, total alkalinity and pH. In addition to water quality analyses, a structured household questionnaire was administered to address water use, sanitation, health, consumption patterns, and socioeconomics. Results showed that more than half of the groundwater samples would be considered of unacceptable quality based on World Health Organization (WHO) standards for E. coli contamination. Low levels of nitrate were found in groundwater, but only one well exceeded WHO standards. The structured questionnaire revealed that some residents were still consuming groundwater despite the access to safer municipal water. In general, the widespread E. coli contamination was not statistically correlated with well depth, latrine proximity, or surface features. Similarly, nitrate concentrations were not significantly correlated with proximity to latrines. On the other hand, nitrate was correlated with well depth, which is expected given the high potential for leaching of anionic highly water soluble compounds. E. coli was significantly correlated with nitrate concentration. Projects targeting the need for clean water need to recognize that households with access to a safe piped municipal water service may still be consuming unsafe groundwater.
Energy Innovation Acceleration Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wolfson, Johanna
The Energy Innovation Acceleration Program (IAP) – also called U-Launch – has had a significant impact on early stage clean energy companies in the Northeast and on the clean energy economy in the Northeast, not only during program execution (2010-2014), but continuing into the future. Key results include: Leverage ratio of 105:1; $105M in follow-on funding (upon $1M investment by EERE); At least 19 commercial products launched; At least 17 new industry partnerships formed; At least $6.5M in revenue generated; >140 jobs created; 60% of assisted companies received follow-on funding within 1 year of program completion; In addition to themore » direct measurable program results summarized above, two primary lessons emerged from our work executing Energy IAP:; Validation and demonstration awards have an outsized, ‘tipping-point’ effect for startups looking to secure investments and strategic partnerships. An ecosystem approach is valuable, but an approach that evaluates the needs of individual companies and then draws from diverse ecosystem resources to fill them, is most valuable of all.« less
Comparison of extraction techniques of robenidine from poultry feed samples.
Wilga, Joanna; Wasik, Agata Kot-; Namieśnik, Jacek
2007-10-31
In this paper, effectiveness of six different commonly applied extraction techniques for the determination of robenidine in poultry feed has been compared. The sample preparation techniques included shaking, Soxhlet, Soxtec, ultrasonically assisted extraction, microwave - assisted extraction and accelerated solvent extraction. Comparison of these techniques was done with respect to the recovery extraction, temperature and time, reproducibility and solvent consumption. Every single extract was subjected to clean - up using aluminium oxide column (Pasteur pipette filled with 1g of aluminium oxide), from which robenidine was eluted with 10ml of methanol. The eluate from the clean-up column was collected in a volumetric flask, and finally it was analysed by HPLC-DAD-MS. In general, all extraction techniques were capable of isolating of robenidine from poultry feed, but the recovery obtained using modern extraction techniques was higher than that obtained using conventional techniques. In particular, accelerated solvent extraction was more superior to other techniques, which highlights the advantages of this sample preparation technique. However, in routine analysis, shaking and ultrasonically assisted extraction is still the preferred method for the solution of robenidine and other coccidiostatics.
NASA Astrophysics Data System (ADS)
Hao, Liting; Zhang, Baogang; Tian, Caixing; Liu, Ye; Shi, Chunhong; Cheng, Ming; Feng, Chuanping
2015-08-01
Bioelectricity generated from the microbial fuel cell (MFC) is applied to the bioelectrical reactor (BER) directly to enhance microbial reduction of vanadium (V) (V(V)) in groundwater. With the maximum power density of 543.4 mW m-2 from the MFC, V(V) removal is accelerated with efficiency of 93.6% during 12 h operation. Higher applied voltage can facilitate this process. V(V) removals decrease with the increase of initial V(V) concentration, while extra addition of chemical oxygen demand (COD) has little effect on performance improvement. Microbial V(V) reduction is enhanced and then suppressed with the increase of conductivity. High-throughput 16S rRNA gene pyrosequencing analysis implies the accumulated Enterobacter and Lactococcus reduce V(V) with products from fermentative microorganisms such as Macellibacteroides. The presentation of electrochemically active bacteria as Enterobacter promotes electron transfers. This study indicates that application of bioelectricity from MFCs is a promising strategy to improve the efficiency of in-situ bioremediation of V(V) polluted groundwater.
NASA Astrophysics Data System (ADS)
Davidsen, Claus; Liu, Suxia; Mo, Xingguo; Rosbjerg, Dan; Bauer-Gottwein, Peter
2014-05-01
Optimal management of conjunctive use of surface water and groundwater has been attempted with different algorithms in the literature. In this study, a hydro-economic modelling approach to optimize conjunctive use of scarce surface water and groundwater resources under uncertainty is presented. A stochastic dynamic programming (SDP) approach is used to minimize the basin-wide total costs arising from water allocations and water curtailments. Dynamic allocation problems with inclusion of groundwater resources proved to be more complex to solve with SDP than pure surface water allocation problems due to head-dependent pumping costs. These dynamic pumping costs strongly affect the total costs and can lead to non-convexity of the future cost function. The water user groups (agriculture, industry, domestic) are characterized by inelastic demands and fixed water allocation and water supply curtailment costs. As in traditional SDP approaches, one step-ahead sub-problems are solved to find the optimal management at any time knowing the inflow scenario and reservoir/aquifer storage levels. These non-linear sub-problems are solved using a genetic algorithm (GA) that minimizes the sum of the immediate and future costs for given surface water reservoir and groundwater aquifer end storages. The immediate cost is found by solving a simple linear allocation sub-problem, and the future costs are assessed by interpolation in the total cost matrix from the following time step. Total costs for all stages, reservoir states, and inflow scenarios are used as future costs to drive a forward moving simulation under uncertain water availability. The use of a GA to solve the sub-problems is computationally more costly than a traditional SDP approach with linearly interpolated future costs. However, in a two-reservoir system the future cost function would have to be represented by a set of planes, and strict convexity in both the surface water and groundwater dimension cannot be maintained. The optimization framework based on the GA is still computationally feasible and represents a clean and customizable method. The method has been applied to the Ziya River basin, China. The basin is located on the North China Plain and is subject to severe water scarcity, which includes surface water droughts and groundwater over-pumping. The head-dependent groundwater pumping costs will enable assessment of the long-term effects of increased electricity prices on the groundwater pumping. The coupled optimization framework is used to assess realistic alternative development scenarios for the basin. In particular the potential for using electricity pricing policies to reach sustainable groundwater pumping is investigated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blount, Gerald; Thibault, Jeffrey; Millings, Margaret
The Savannah River Site (SRS) is owned and administered by the US Department of Energy (DOE). SRS covers an area of approximately 900 square kilometers. The General Separation Area (GSA) is located roughly in the center of the SRS and includes: radioactive material chemical separations facilities, radioactive waste tank farms, a variety of radioactive seepage basins, and the radioactive waste burial grounds. Radioactive wastes were disposed in the GSA from the mid-1950s through the mid-1990s. Radioactive operations at the F Canyon began in 1954; radioactive operations at H Canyon began in 1955. Waste water disposition to the F and Hmore » Seepage Basins began soon after operations started in the canyons. The Old Radioactive Waste Burial Ground (ORWBG) began operations in 1952 to manage solid waste that could be radioactive from all the site operations, and ceased receiving waste in 1972. The Mixed Waste Management Facility (MWMF) and Low Level Radioactive Waste Disposal Facility (LLRWDF) received radioactive solid waste from 1969 until 1995. Environmental legislation enacted in the 1970s, 1980s, and 1990s led to changes in waste management and environmental cleanup practices at SRS. The US Congress passed the Clean Air Act in 1970, and the Clean Water Act in 1972; the Resource Conservation and Recovery Act (RCRA) was enacted in 1976; the Comprehensive Environmental Response Compensation, and Liability Act (CERCLA) was enacted by Congress in 1980; the Federal Facilities Compliance Act (FFCA) was signed into law in 1992. Environmental remediation at the SRS essentially began with a 1987 Settlement Agreement between the SRS and the State of South Carolina (under the South Carolina Department of Health and Environmental Control - SCDHEC), which recognized linkage between many SRS waste management facilities and RCRA. The SRS manages several of the larger groundwater remedial activities under RCRA for facilities recognized early on as environmental problems. All subsequent environmental remediation projects tend to be managed under tri-party agreement (DOE, Environmental Protection Agency, and SCDHEC) through the Federal Facilities Agreement. During 25 years of environmental remediation SRS has stabilized and capped seepage basins, and consolidated and capped waste units and burial grounds in the GSA. Groundwater activities include: pump and treat systems in the groundwater, installation of deep subsurface barrier systems to manage groundwater flow, in situ chemical treatments in the groundwater, and captured contaminated groundwater discharges at the surface for management in a forest irrigation system. Over the last 25 years concentrations of contaminants in the aquifers beneath the GSA and in surface water streams in the GSA have dropped significantly. Closure of 65 waste sites and 4 RCRA facilities has been successfully accomplished. Wastes have been successfully isolated in place beneath a variety of caps and cover systems. Environmental clean-up has progressed to the stage where most of the work involves monitoring, optimization, and maintenance of existing remedial systems. Many lessons have been learned in the process. Geotextile covers outperform low permeability clay caps, especially with respect to the amount of repairs required to upkeep the drainage layers as the caps age. Passive, enhanced natural processes to address groundwater contamination are much more cost effective than pump and treat systems. SRS operated two very large pump and treat systems at the F and H Seepage Basins to attempt to limit the release of tritium to Fourmile Branch, a tributary of the Savannah River. The systems were designed to extract contaminated acidic groundwater, remove all contamination except tritium (not possible to remove the tritium from the water), and inject the tritiated groundwater up-gradient of the source area and the plume. The concept was to increase the travel time of the injected water for radioactive decay of the tritium. The two systems were found to be non-effective and potentially mobilizing more contamination. SRS invested approximately $50 million in construction and approximately $100 million in 6 years of operation. The H Seepage Basin pump and treat system was replaced by a series of subsurface barriers that alters the groundwater velocity; the F Seepage Basin pump and treat system was replaced by subsurface barriers forming a funnel and gate augmented by chemical treatment within the gates. These replacement systems are mostly passive and cost approximately $13 million to construct, and have reduced the tritium flux to Fourmile Branch, in these plumes, by over 70%. SRS manages non-acidic tritiated groundwater releases to Fourmile Branch from the southwest plume of the MWMF with a forest irrigation system. Tritiated water is captured with a sheetpile dam below the springs that caused releases to Fourmile Branch. Water from the irrigation pond is pumped to a filter plant prior to irrigation of approximately 26 hectares of mixed forest and developing pine plantation. SRS has almost achieved a 70% reduction in tritium flux to the Branch from this plume. The system cost approximately $5 million to construct with operation cost of approximately $500K per year. In conclusion, many lessons have been learned in 25 years of relatively aggressive remedial activities in the GSA. Geotextile covers outperform low permeability clay caps, especially with respect to the amount of repairs required to upkeep the drainage layers as the caps age. Passive, enhanced natural processes to address groundwater contamination are much more cost effective than pump and treat systems. In water management situations with non-accumulative contaminants (tritium, VOCs, etc.) irrigation in a forest setting can be very effective.« less
NASA Astrophysics Data System (ADS)
Grimmeisen, Felix; Zemann, Moritz; Goeppert, Nadine; Goldscheider, Nico
2016-06-01
Leaky sewerage and water distribution networks are an enormous problem throughout the world, specifically in developing countries and regions with water scarcity. Especially in many arid and semi-arid regions, intermittent water supply (IWS) is common practice to cope with water shortage. This study investigates the combined influence of urban activities, IWS and water losses on groundwater quality and discusses the implications for water management. In the city of As-Salt (Jordan), local water supply is mostly based on groundwater from the karst aquifer that underlies the city. Water is delivered to different supply zones for 24, 48 or 60 h each week with drinking water losses of around 50-60%. Fecal contamination in groundwater, mostly originating from the likewise leaky sewer system is a severe challenge for the local water supplier. In order to improve understanding of the local water cycle and contamination dynamics in the aquifer beneath the city, a down gradient spring and an observation well were chosen to identify contaminant occurrence and loads. Nitrate, Escherichia coli, spring discharge and the well water level were monitored for 2 years. Autocorrelation analyses of time series recorded during the dry season revealed weekly periodicity of spring discharge (45 ± 3.9 L s-1) and NO3-N concentrations (11.4 ± 0.8 mg L-1) along with weekly varying E. coli levels partly exceeding 2.420 MPN 100 mL-1. Cross-correlation analyses demonstrate a significant and inverse correlation of nitrate and discharge variations which points to a periodic dilution of contaminated groundwater by freshwater from the leaking IWS being the principal cause of the observed fluctuations. Contaminant inputs from leaking sewers appear to be rather constant. The results reveal the distinct impact of leaking clean IWS on the local groundwater and subsequently on the local water supply and therefore demonstrate the need for action regarding the mitigation of groundwater contamination and reduction of network losses from sewer leakage. Furthermore, these investigations contribute to an improved understanding of urban water cycle systems in the Middle-East which may help water managers in the region to conserve precious resources.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
This paper responds to the Development Committee Communique of April 2006 requesting the World Bank to review existing financial instruments and explore the potential value of new financial instruments to accelerate investment in clean energy. It builds on the report 'Clean Energy and Development: Towards an Investment Framework' that was presented to the Development Committee at the April 2006 Spring Meeting and concludes: The major financing gap for the energy for development and energy access agendas can be met by deepening and broadening energy sector policy reform to attract private sector investments and additional public sector financing. A long-term stablemore » global regulatory framework, with differentiated responsibilities, is needed to stimulate private investments and provide predictability. The Bank proposes the development of a number of options to accelerate the transition to a low carbon economy. Risks of weather-related disasters need to be integrated into poverty and sustainable development strategies with a combination of public and private sector resources. Clean energy will address the following issues that affect poor people and undermine progress on many of the Millennium Development Goals: Pollution at the household level, especially indoor air pollution, which adversely affects human health; Environmental impacts at the local, national and regional level, including urban air pollution and acid deposition, which affects human health and ecological systems; and The adverse impacts of greenhouse gas emissions from the production of energy on agricultural productivity, water resources, human health, human settlements and ecological systems. 11 figs., 2 tabs., 2 annexes.« less
Land subsidence in the San Joaquin Valley, California, USA, 2007-2014
NASA Astrophysics Data System (ADS)
Sneed, M.; Brandt, J. T.
2015-11-01
Rapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater pumping, groundwater-level declines, and land subsidence. Differential land subsidence has reduced the flow capacity of water-conveyance systems in these areas, exacerbating flood hazards and affecting the delivery of irrigation water. Vertical land-surface changes during 2007-2014 were determined by using Interferometric Synthetic Aperture Radar (InSAR), Continuous Global Positioning System (CGPS), and extensometer data. Results of the InSAR analysis indicate that about 7600 km2 subsided 50-540 mm during 2008-2010; CGPS and extensometer data indicate that these rates continued or accelerated through December 2014. The maximum InSAR-measured rate of 270 mm yr-1 occurred in the El Nido area, and is among the largest rates ever measured in the SJV. In the Pixley area, the maximum InSAR-measured rate during 2008-2010 was 90 mm yr-1. Groundwater was an important part of the water supply in both areas, and pumping increased when land use changed or when surface water was less available. This increased pumping caused groundwater-level declines to near or below historical lows during the drought periods 2007-2009 and 2012-present. Long-term groundwater-level and land-subsidence monitoring in the SJV is critical for understanding the interconnection of land use, groundwater levels, and subsidence, and evaluating management strategies that help mitigate subsidence hazards to infrastructure while optimizing water supplies.
Effects of chlorinated solvents on four species of North American amphibians.
McDaniel, T V; Martin, P A; Ross, N; Brown, S; Lesage, S; Pauli, B D
2004-07-01
Tetrachloroethylene (PCE), a dry cleaning and degreasing solvent, can enter groundwater through accidental leaks or spills, and concentrations as high as 75 mg/L have been reported in Canadian aquifers. Amphibians in wetlands receiving contaminated groundwater may be exposed to PCE and its degradation products, but little information is available on the impacts of these compounds on indigenous amphibian species. Acute (96-h static renewal) exposures to PCE and its major degradation products, trichloroethylene (TCE) and cisand trans-dichloroethylene, were conducted on embryos of four North American amphibian species: wood frogs (Rana sylvatica), green frogs (R. clamitans), American toads (Bufo americanus), and spotted salamanders (Ambystoma maculatum). Subsequently, chronic exposures to PCE and TCE were conducted with the larvae of American toads. Both PCE and TCE were teratogenic to amphibian embryos; median effective concentrations (EC50s) for developmental deformities produced by PCE and TCE exposure for wood frogs and green frogs were 12 and 40 mg/L, respectively. Embryonic survivorship, however, was not compromised at these concentrations. American toads were less sensitive; the EC50 for developmental abnormalities was not attained at the highest test concentrations, 45 and 85 mg/L PCE and TCE, respectively. These results are pertinent in assessing the impact of groundwater pollution on an aquifer-fed wetland.
Natarajan, Seenivasan; Stamps, Robert H; Ma, Lena Q; Saha, Uttam K; Hernandez, Damaris; Cai, Yong; Zillioux, Edward J
2011-01-30
A large-scale hydroponic system to phytoremediate arsenic-contaminated groundwater using Pteris vittata (Chinese brake fern) was successfully tested in a field. In this 30-wk study, three frond-harvesting regimes (all, mature, and senescing fronds) and two water-refilling schemes to compensate for evapotranspiration (high-As water of 140-180 μg/L and low-As water of <7 μg/L) were investigated. Two experiments (Cycle 1 and Cycle 2) were conducted using the same plants in 24 tanks with each containing 600 L of arsenic-contaminated groundwater and 32 ferns. During Cycle 1 and with initial As of 140 μg/L, As in tanks refilled with low-As water was reduced to <10 μg/L in 8 wks compared to <10 μg/L in 17 wks in tanks refilled with high-As water. During Cycle 2 and with initial As of 180 μg/L, the remediation time was reduced by 2-5 wks, indicating that more established ferns were more efficient. In areas where clean water is limiting, refilling high-As water coupled with harvesting senescing fronds is recommended for more effective As phytoremediation. Published by Elsevier B.V.
Key NASA, USAF and federal officials sign a Memorandum of Agreement on groundwater cleanup
NASA Technical Reports Server (NTRS)
1999-01-01
Walter W. Kovalick Jr., Ph.D., director of Technology Innovation Office for the U.S. Environmental Protection Agency, addresses representatives from Kennedy Space Center, the 45th Space Wing, and various federal environmental agencies gathered to attend a Memorandum of Agreement (MOA) signing, taking place at the site of Launch Complex 34. The MOA formalizes the cooperative efforts of the federal agencies in ground-water cleanup initiatives. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally. Other attendees included Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; and Roy Bridges Jr., director of John F. Kennedy Space Center.
Hildebrandt, Alain; Lacorte, Sílvia; Barceló, Damià
2007-02-01
Gas chromatography-mass spectrometry (GC/MS) was employed for the determination of 30 widely used pesticides including various transformation products and alkylphenols in water and agricultural soils with the aim of assessing the impact of these compounds in agricultural soils and the underlying aquifer. The extraction, clean-up, and analytical procedures were optimized for both water and soil samples to provide a highly robust method capable of determining target analytes at the ppb-ppt level with high precision. For water samples, different solid-phase extraction cartridges and conditions were optimized; similarly, pressurized liquid extraction conditions were tested to provide interference-free extracts and high sensitivity. Instrumental LODs of 3-4 pg were obtained. The multi-residue extraction procedures were applied to the analysis of groundwaters and agricultural soils from the Ebro river basin (NE Spain). Most ubiquitous herbicides detected were triazines but some acetanilides and organophosphorus pesticides were also found; the pesticide additive tributylphosphate was found in all water samples. Levels varied between 0.57 and 5.37 microg/L in groundwater, whereas nonylphenol was the sole compound detected in soil. Alkylphenols are used as adjuvants in pesticide formulations and are present in sludges employed as soil fertilizers. Occurrence was found to be similar to other environmental studies.
NASA Astrophysics Data System (ADS)
Uhlemann, Sebastian; Kuras, Oliver; Richards, Laura A.; Naden, Emma; Polya, David A.
2017-10-01
Despite being rich in water resources, many areas of South East Asia face difficulties in securing clean water supply. This is particularly problematic in regions with a rapidly growing population. In this study, the spatial variability of the thickness of a clay layer, controlling surface - groundwater interactions that affect aquifer vulnerability, was investigated using electrical resistivity tomography (ERT). Data were acquired along two transects, showing significant differences in the imaged resistivities. Borehole samples were analyzed regarding particle density and composition, and linked to their resistivity. The obtained relationships were used to translate the field electrical resistivities into lithologies. Those revealed considerable variations in the thickness of the clay layer, ranging from 0 m up to 25 m. Geochemical data, highlighting zones of increased ingress of surface water into the groundwater, confirmed areas of discontinuities in the clay layer, which act as preferential flow paths. The results may guide urban planning of the Phnom Penh city expansion, in order to supply the growing population with safe water. The presented approach of using geophysics to estimate groundwater availability, accessibility, and vulnerability is not only applicable to Kandal Province, Cambodia, but also to many other areas of fast urbanization in South East Asia and beyond.
A re-evaluation of the taste and odour of methyl tertiary butyl ether (MTBE) in drinking water.
Suffet, I H
2007-01-01
Methyl tertiary butyl ether (MTBE) is a gasoline additive that has been found in groundwater when an underground gasoline storage tank leaks. Although dependent on the clean-up standards that are applied, clean-up costs have been estimated in the US alone to be in the billions of dollars. MTBE is considered primarily a taste and odour concern and not a toxicity issue at concentrations found in drinking water. Thus, the clean-up of MTBE problems is controlled by the MTBE odour threshold concentration (OTC). The level of clean-up and associated differential of millions of dollars is a matter of concern for water purveyors and well owners. A 1993 study of nine OTC studies showed the OTC of MTBE in water to be between 0.04 and 0.06 microg/L, a level over two orders of magnitude less than eight other studies. This 1993 study was repeated at the original laboratory in 2004 and is reported in this paper. The laboratory's quality control programme and ability to repeat one of the eight other studies indicated the laboratory was qualified to repeat its original OTC study. The flavour and odour detection threshold range in the 1993 study, however, could not be confirmed by trained assessors repeating the original study in 2004. The inconsistencies in the data and the high detection on water blanks indicate that the dilution series of the test solutions for the 1993 study were mainly at subthreshold levels. Therefore, the original study of 1993 is not a valid OTC study for MTBE and should not be used to develop drinking water and clean-up standards. The OTC of MTBE is over 15 microg/L for the eight valid studies.
NASA Astrophysics Data System (ADS)
Jang, E.; Kalbacher, T.; He, W.; Shao, H.; Schueth, C.; Kolditz, O.
2014-12-01
Nitrate contamination in shallow groundwater is still one of the common problems in many countries. Because of its high solubility and anionic nature, nitrate can easily leach through soil and persist in groundwater for decades. High nitrate concentration has been suggested as a major cause of accelerated eutrophication, methemoglobinemia and gastric cancer. There are several factors influencing the fate of nitrate in groundwater system, which is e.g. distribution of N- sources to soil and groundwater, distribution and amount of reactive substances maintaining denitrification, rate of nitrate degradation and its kinetics, and geological characteristics of the aquifer. Nitrate transport and redox transformation processes are closely linked to complex and spatially distributed physical and chemical interaction, therefore it is difficult to predict and quantify in the field and laboratory experiment. Models can play a key role in elucidation of nitrate reduction pathway in groundwater system and in the design and evaluation of field tests to investigate in situ remediation technologies as well. The goal of the current study is to predict groundwater vulnerability to nitrate, to identify functional zones of denitrification in heterogeneous aquifer systems and to describe the uncertainty of the predictions due to scale effects. For this aim, we developed a kinetic model using multi-component mass transport code OpenGeoSys coupling with IPhreeqc module of the geochemical solver PHREEQC. The developed model included sequential aerobic and nitrate-based respiration, multi-Monod kinetics, multi-species biogeochemical reactions, and geological characteristics of the groundwater aquifer. Moreover water-rock interaction such as secondary mineral precipitation was also included in this model. In this presentation, we focused on the general modelling approach and present the simulation results of nitrate transport simulation in a hypothetical aquifer systems based on data from Hessian Ried, an important groundwater resource for the densely populated Rhine-Main region in Germany.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Devanathan, Ram
Here, more than a billion people do not have access to clean water globally and millions of people die every year from water borne diseases. Human activity has resulted in depletion of groundwater, seawater intrusion in coastal aquifers, pollution of water resources, ecological damage, and resultant threats to the world’s freshwater, food supply, security, and prosperity. To address this challenge, there is a pressing need to produce clean water from seawater, brackish groundwater, and waste water. Current desalination methods are energy intensive and produce adverse environmental impact. At the same time, energy production consumes large quantities of water and createsmore » waste water that needs to be treated with further energy input. Water treatment with membranes that separate water molecules from ions, pathogens and pollutants has been proposed as an energy-efficient solution to the fresh water crisis. Recently, membranes based on carbon nanotubes, graphene and graphene oxide (GO) have garnered considerable interest for their potential in desalination. Of these, GO membranes hold the promise of inexpensive production on a large scale but swell when immersed in water. The swollen membrane allows not only water molecules but also ions, such as Na + and Mg 2+, to pass through. Abraham and coworkers show that the interlayer spacing in a GO laminar membrane can be tuned to a certain value and then fixed by physically restraining the membrane from swelling. When the authors reduced the spacing systematically in steps from 9.8 Å to 7.4 Å, the ion permeation rate was reduced by two orders of magnitude while the water permeation rate was only halved.« less
Ion sieving and desalination: Energy penalty for excess baggage
Devanathan, Ram
2017-04-03
Here, more than a billion people do not have access to clean water globally and millions of people die every year from water borne diseases. Human activity has resulted in depletion of groundwater, seawater intrusion in coastal aquifers, pollution of water resources, ecological damage, and resultant threats to the world’s freshwater, food supply, security, and prosperity. To address this challenge, there is a pressing need to produce clean water from seawater, brackish groundwater, and waste water. Current desalination methods are energy intensive and produce adverse environmental impact. At the same time, energy production consumes large quantities of water and createsmore » waste water that needs to be treated with further energy input. Water treatment with membranes that separate water molecules from ions, pathogens and pollutants has been proposed as an energy-efficient solution to the fresh water crisis. Recently, membranes based on carbon nanotubes, graphene and graphene oxide (GO) have garnered considerable interest for their potential in desalination. Of these, GO membranes hold the promise of inexpensive production on a large scale but swell when immersed in water. The swollen membrane allows not only water molecules but also ions, such as Na + and Mg 2+, to pass through. Abraham and coworkers show that the interlayer spacing in a GO laminar membrane can be tuned to a certain value and then fixed by physically restraining the membrane from swelling. When the authors reduced the spacing systematically in steps from 9.8 Å to 7.4 Å, the ion permeation rate was reduced by two orders of magnitude while the water permeation rate was only halved.« less
Successful implementation of property cleanup under the Ohio and the Texas voluntary programs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roffman, A.
1999-07-01
Cleanups of two properties, one located in Ohio and the other in Texas were successfully implemented. The facilities were printing plants that manufactured printed material and forms for commercial and industrial use. Primary products and chemicals involved in the manufacturing of the forms included ink, petroleum products and cleaning solvents. The Ohio property underwent a successful cleanup under the Ohio EPA Voluntary Action Program (VAP). It met the Ohio EPA residential land use cleanup standards for soil and shallow groundwater. A No Further Action letter has been submitted to the state and it resulted in the issuance of a Covenantmore » Not to Sue. The Texas facility underwent a successful cleanup under the Texas Natural Resource Conservation Commission (TNRCC) Voluntary Cleanup Program (VCP). It resulted in the issuance of a Certificate of Completion (COC) for residential land use for soil, and a conditional COC for industrial land use for the shallow groundwater.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
The objectives of the closure assessment were to determine the extent of contaminated soil adjacent to the USTs requiring excavation, to provide documentation of soil and groundwater conditions following excavation, and to document closure activities in accordance with applicable VADEQ regulations. During closure activities, ASI provided technical support to the Base to ensure that the UST removal contractor (E K, Inc.) hereinafter referred to as the Contractor was in compliance with the technical requirements (as specified in the Plans and Specifications for Removal of Abandoned Underground Storage Tanks, Virginia Air National Guard, Richmond International Airport, Sandston, VA., dated July 1991more » and revised April 1992, and Addendum Numbers 1 through 7) of the contract. ASI was also responsible for collecting soil and/or groundwater closure samples from the excavations, and providing off-site fixed based laboratory analysis to verify clean conditions within the excavations.« less
Risk Communication of Groundwater Quality in Northern Malawi, Africa
NASA Astrophysics Data System (ADS)
Holm, R.
2011-12-01
Malawi lies in Africa's Great Rift Valley. Its western border is defined by Lake Malawi, the third largest lake in Africa. Over 80% of Malawians live in rural areas and 90% of the labor force is associated with agriculture. More than half of the population lives below the poverty line. Area characteristics indicate a high likelihood of nitrate and total coliform in community drinking water. Infants exposed to high nitrate are at risk of developing methemoglobinemia. In addition, diarrheal diseases from unsafe drinking water are one of the top causes of mortality in children under five. Without sufficient and sustainable supplies of clean water, these challenges will continue to threaten Malawi's ability to overcome the devastating impact of diarrheal diseases on its population. Therefore, Malawi remains highly dependent on outside assistance and influence to reduce or eliminate the threat posed by unsafe drinking water. This research presents a literature review of nitrate and total coliform groundwater quality and a proposed risk communication plan for drinking water in northern Malawi.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Addy, Susan E.A.; Gadgil, Ashok J.; Kowolik, Kristin
2009-12-01
Today, 35-77 million Bangladeshis drink arsenic-contaminated groundwater from shallow tube wells. Arsenic remediation efforts have focused on the development and dissemination of household filters that frequently fall into disuse due to the amount of attention and maintenance that they require. A community scale clean water center has many advantages over household filters and allows for both chemical and electricity-based technologies to be beneficial to rural areas. Full cost recovery would enable the treatment center to be sustainable over time. ElectroChemical Arsenic Remediation (ECAR) is compatible with community scale water treatment for rural Bangladesh. We demonstrate the ability of ECAR tomore » reduce arsenic levels> 500 ppb to less than 10 ppb in synthetic and real Bangladesh groundwater samples and examine the influence of several operating parameters on arsenic removal effectiveness. Operating cost and waste estimates are provided. Policy implication recommendations that encourage sustainable community treatment centers are discussed.« less
Groundwater cleanup demonstrations at Complex 34, CCAS
NASA Technical Reports Server (NTRS)
2000-01-01
On top of the block house at Launch Complex 34, representatives from environmental and Federal agencies hear from Laymon Gray, with Florida State University, about the environmental research project that involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA in a groundwater cleanup effort. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program, which used the complex, in the 60s. The group formed the Interagency NDAPL Consortium (IDC) to study three contamination cleanup technologies: Six Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. In the background (left) can be seen the cement platform and walkway from the block house to the pad. Beyond it is the Atlantic Ocean. KSC hosted a two-day conference that presented information and demonstrations of the three technologies being tested at the site.
An Environmental Innovation: The Sewer Mouse
NASA Technical Reports Server (NTRS)
1979-01-01
In the effort to clean up America's waters, there is a little-known complicating factor: because they leak, sewer systems in many American cities are causing rather than preventing pollution of rivers and lakes. Fixing the leaks is difficult because their locations are unknown. Maintenance crews can't tear up a whole city looking for cracks in the pipes; they must first determine which areas are most likely suspects. An aerospace spinoff is providing help in that regard. The problem starts with heavy rains. Rainwater naturally flows into the sewers from streets, but sewage systems are designed to accommodate it. However, they are not designed to handle the additional flow of "groundwater", rain absorbed by the earth which seeps into the sewers through leaks in pipes and sewer walls. After a storm, groundwater seepage can increase the waterflow to deluge proportions, with the result that sewage treatment plants are incapable of processing the swollen flow. When that happens the sluices must be opened, dumping raw sewage into rivers and lakes.
Unterdruck-Verdampfer-Brunnen (UVB): An in situ system for remediation of contaminated aquifers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simon, M.A.; Argus, R.R.; Hough, B.L.
Traditionally, contaminated groundwater is pumped to a surface facility for treatment, often by air stripping. An innovative technology, the Unterdruck-Verdampfer-Brunnen (UVB), German for Vacuum Vaporizing Well, is an in situ groundwater remediation technology that combines air-lift pumping and air stripping to clean aquifers contaminated with volatile compounds. Additionally, the developer claims that in some cases the technology is capable of simultaneous recovery of soil gas from the vadose zone. An evaluation of this process is discussed in this abstract. The UVB technology is a process patented by IEG mbH in Reutlingen, Germany. IEG Technologies, Inc., located in Charlotte, NC, marketsmore » the technology in North America. IEG teamed with Roy F. Weston, Inc. to demonstrate the UVB technology at March Air Force Base (AFB), CA. March AFB allowed the US EPA Superfund Innovative Technology Evaluation (SITE) program to evaluate the technology. The SITE program retained PRC Environmental, Inc. to evaluate the performance of the UVB system at March.« less
Department of Energy Recovery Act Investment in Biomass Technologies
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2010-11-01
The American Recovery and Reinvestment Act of 2009 (Recovery Act) provided more than $36 billion to the Department of Energy (DOE) to accelerate work on existing projects, undertake new and transformative research, and deploy clean energy technologies across the nation. Of this funding, $1029 million is supporting innovative work to advance biomass research, development, demonstration, and deployment.
Evaluation of Composting Implementation: A Literature Review
1990-07-13
toxic intermediates and reaction products ; and 3. the potential for additional contami-ation of groundwaters and soils . General conclusions from these... Soil . In: Compost: Production , Quality, and Use, Proceedings of a Symposium Organized by the Commission of the European Communities, M. DeBertoldi, M...Historically, composting has been used to accelerate the biodegradation of a variety of organic wastes from agricultural products (Fujio et al., 1986
Impact Of Landfill Closure Designs On Long-Term Natural Attenuation Of Chlorinated Hydrocarbons
2002-03-01
chlorinated aliphatic hydrocarbons (CAHs) (i.e., chlorinated solvents) in landfills and landfill- leachate -contaminated groundwater. The project was divided...attenuation rather than expensive leachate collection and treatment systems. At some landfills, surface infiltration may accelerate the leaching of...the “source” and reduce the time required for biological stabilization of the landfilled waste. Recirculation of landfill leachate could also be
Faust, Derek R; Moore, Matthew T; Emison, Gerald Andrews; Rush, Scott A
2016-05-01
The 1972 Clean Water Act was passed to protect chemical, physical, and biological integrity of United States' waters. The U.S. Environmental Protection Agency and U.S. Army Corps of Engineers codified a new "waters of the United States" rule on June 29, 2015, because several Supreme Court case decisions caused confusion with the existing rule. Climate change could affect this rule through connectivity between groundwater and surface waters; floodplain waters and the 100-year floodplain; changes in jurisdictional status; and sea level rise on coastal ecosystems. Four approaches are discussed for handling these implications: (1) "Wait and see"; (2) changes to the rule; (3) use guidance documents; (4) Congress statutorily defining "waters of the United States." The approach chosen should be legally defensible and achieved in a timely fashion to provide protection to "waters of the United States" in proactive consideration of scientifically documented effects of climate change on aquatic ecosystems.
Cho, Youngsoo; Cattrall, Robert W; Kolev, Spas D
2018-01-05
Thiocyanate is present in gold mine tailings waters in concentrations up to 1000mgL -1 and this has a serious environmental impact by not allowing water reuse in the flotation of gold ore. This significantly increases the consumption of fresh water and the amount of wastewater discharged in tailings dams. At the same time thiocyanate in tailings waters often leads to groundwater contamination. A novel continuous membrane-based method for the complete clean-up of thiocyanate in concentrations as high as 1000mgL -1 from its aqueous solutions has been developed. It employs a flat sheet polymer inclusion membrane (PIM) of composition 70wt% PVC, 20wt% Aliquat 336 and 10wt% 1-tetradecanol which separates counter-current streams of a feed thiocyanate solution and a 1M NaNO 3 receiving solution. The PIM-based system has been operated continuously for 45days with 99% separation efficiency. The volume of the receiving solution has been drastically reduced by recirculating it and continuously removing thiocyanate by precipitating it with in-situ generated Cu(I). The newly developed PIM-based thiocyanate clean-up method is environmentally friendly in terms of reagent use and inexpensive with respect to both equipment and running costs. Copyright © 2017 Elsevier B.V. All rights reserved.
Chong, Andrea D; Mayer, K Ulrich
2017-09-01
Historical heavy use of chlorinated solvents in conjunction with improper disposal practices and accidental releases has resulted in widespread contamination of soils and groundwater in North America and worldwide. As a result, remediation of chlorinated solvents is required at many sites. For source zone treatment, common remediation strategies include in-situ chemical oxidation (ISCO) using potassium or sodium permanganate, and the enhancement of biodegradation by primary substrate addition. It is well known that these remediation methods tend to generate gas (carbon dioxide (CO 2 ) in the case of ISCO using permanganate, CO 2 and methane (CH 4 ) in the case of bioremediation). Vigorous gas generation in the presence of chlorinated solvents, which are categorized as volatile organic contaminants (VOCs), may cause gas exsolution, ebullition and stripping of the contaminants from the treatment zone. This process may lead to unintentional 'compartment transfer', whereby VOCs are transported away from the contaminated zone into overlying clean sediments and into the vadose zone. To this extent, benchtop column experiments were conducted to quantify the effect of gas generation during remediation of the common chlorinated solvent trichloroethylene (TCE/C 2 Cl 3 H). Both ISCO and enhanced bioremediation were considered as treatment methods. Results show that gas exsolution and ebullition occurs for both remediation technologies. Facilitated by ebullition, TCE was transported from the source zone into overlying clean groundwater and was subsequently released into the column headspace. For the case of enhanced bioremediation, the intermediate degradation product vinyl chloride (VC) was also stripped from the treatment zone. The concentrations measured in the headspace of the columns (TCE ∼300ppm in the ISCO column, TCE ∼500ppm and VC ∼1380ppm in the bioremediation column) indicate that substantial transfer of VOCs to the vadose zone is possible. These findings provide direct evidence for the unintended spreading of contaminants as a result of remediation efforts, which can, under some circumstances, result in enhanced risks for soil vapour intrusion. Copyright © 2017 Elsevier B.V. All rights reserved.
Urbanization effect on groundwater quality (Paleohydrogeological study)
NASA Astrophysics Data System (ADS)
Sabri, Raghid; Merkel, Broder; Tichomirowa, Marion
2015-04-01
Speleothem growing in caves usually contain hydrological information. Carbonates precipitation growing in tunnels under cities contain information about anthropological influence on water system. Carbonate samples were taken from Roman tunnels in rural and urban area in Nablus district- Palestine. These laminated samples were analyzed for rare earth elements (REE), 13C and 18O. For REE, five samples were examined, each lamination was extracted and diluted with 0.1 ml 65% HNO3 and measured using ICP-MS. Yet, limited number of lamination was used for isotope analysis using Isotope ratio mass spectrometry. Total concentration of rare earth elements were calculated for each of the five samples. In all examined samples, the newer laminations show higher peaks than the older one of each sample. On the other hand, one sample (8 measurements) of 13C show values between -31.6° and -36°. These values mean that the carbonate is from organic origin. In an urban area, wastewater infiltration into groundwater system can be the source of organic matter. 18O measurements show continues enrichments within the growth of the carbonate. This increase of the 18O values reflects drier weather. Our results can be explained by the increase of water consumption in the household in the recent 100 years, rather than the increase of using detergents and cleaning products which have influenced groundwater quality as appeared in the carbonate samples. On the other hand, 18O results could be linked with the expansion of the building up area in the city and subsequently reduction of groundwater recharge
Potential groundwater contribution to Amazon evapotranspiration
NASA Astrophysics Data System (ADS)
Fan, Y.; Miguez-Macho, G.
2010-07-01
Climate and land ecosystem models simulate a dry-season vegetation stress in the Amazon forest, but observations show enhanced growth in response to higher radiation under less cloudy skies, indicating an adequate water supply. Proposed mechanisms include larger soil water store and deeper roots in nature and the ability of roots to move water up and down (hydraulic redistribution). Here we assess the importance of the upward soil water flux from the groundwater driven by capillarity. We present a map of water table depth from observations and groundwater modeling, and a map of potential capillary flux these water table depths can sustain. The maps show that the water table beneath the Amazon can be quite shallow in lowlands and river valleys (<5 m in 36% and <10 m in 60% of Amazonia). The water table can potentially sustain a capillary flux of >2.1 mm day-1 to the land surface averaged over Amazonia, but varies from 0.6 to 3.7 mm day-1 across nine study sites. Current models simulate a large-scale reduction in dry-season photosynthesis under today's climate and a possible dieback under projected future climate with a longer dry season, converting the Amazon from a net carbon sink to a source and accelerating warming. The inclusion of groundwater and capillary flux may modify the model results.
Chiang, Kai-Wei; Lin, Cheng-An; Kuo, Chung-Yen
2015-01-01
The integration of the Strapdown Inertial Navigation System and Global Navigation Satellite System (SINS/GNSS) has been implemented for land-based gravimetry and has been proven to perform well in estimating gravity. Based on the mGal-level gravimetry results, this research aims to construct and develop a land-based SINS/GNSS gravimetry device containing a navigation-grade Inertial Measurement Unit. This research also presents a feasibility analysis for groundwater resource detection. A preliminary comparison of the kinematic velocities and accelerations using multi-combination of GNSS data including Global Positioning System, Global Navigation Satellite System, and BeiDou Navigation Satellite System, indicates that three-system observations performed better than two-system data in the computation. A comparison of gravity derived from SINS/GNSS and measured using a relative gravimeter also shows that both agree reasonably well with a mean difference of 2.30 mGal. The mean difference between repeat measurements of gravity disturbance using SINS/GNSS is 2.46 mGal with a standard deviation of 1.32 mGal. The gravity variation because of the groundwater at Pingtung Plain, Taiwan could reach 2.72 mGal. Hence, the developed land-based SINS/GNSS gravimetry can sufficiently and effectively detect groundwater resources. PMID:26426019
Chiang, Kai-Wei; Lin, Cheng-An; Kuo, Chung-Yen
2015-09-29
The integration of the Strapdown Inertial Navigation System and Global Navigation Satellite System (SINS/GNSS) has been implemented for land-based gravimetry and has been proven to perform well in estimating gravity. Based on the mGal-level gravimetry results, this research aims to construct and develop a land-based SINS/GNSS gravimetry device containing a navigation-grade Inertial Measurement Unit. This research also presents a feasibility analysis for groundwater resource detection. A preliminary comparison of the kinematic velocities and accelerations using multi-combination of GNSS data including Global Positioning System, Global Navigation Satellite System, and BeiDou Navigation Satellite System, indicates that three-system observations performed better than two-system data in the computation. A comparison of gravity derived from SINS/GNSS and measured using a relative gravimeter also shows that both agree reasonably well with a mean difference of 2.30 mGal. The mean difference between repeat measurements of gravity disturbance using SINS/GNSS is 2.46 mGal with a standard deviation of 1.32 mGal. The gravity variation because of the groundwater at Pingtung Plain, Taiwan could reach 2.72 mGal. Hence, the developed land-based SINS/GNSS gravimetry can sufficiently and effectively detect groundwater resources.
Potential contribution of groundwater to dry-season ET in the Amazon
NASA Astrophysics Data System (ADS)
Miguez-Macho, Gonzalo; Fan, Ying
2010-05-01
Climate and land ecosystem models simulate vegetation stress in the Amazon forest in the dry season, but observations show enhanced growth in response to higher radiation under less cloudy skies indicating an adequate water supply. The question is: how does the vegetation obtain sufficient water, and what is missing in the models? Shallow model soil and rooting depth is a factor; the ability of roots to move water up and down (hydraulic redistribution) may be another, but another cause may lie in the buffering effect of the groundwater found in nature but absent in models. We present observational and modeling evidence that the vast groundwater store, consequence of high annual rainfall combined with poor drainage in the Amazon, may provide a stable source for dry-season photosynthesis. The water table beneath the Amazon is sufficiently shallow (38% area <5m and 63% area <10m deep) as to contribute >2mm/day to dry-season evapotranspiration, a non-negligible portion of tower-observed flux of 3-4mm/day, the latter including canopy-interception loss and open-water evaporation. This may have important implications to our understanding of Amazonia ecosystem response and feedback to climate change. Current models, lacking groundwater, predict a significant reduction in dry-season photosynthesis under current climate and large-scale dieback under projected future climate converting the Amazon from a net carbon sink to a net source and accelerating warming. If groundwater is considered in the models, the magnitude of the responses and feedbacks may be reduced.
Introduction to Superconducting RF Structures and the Effect of High Pressure Rinsing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tajima, Tsuyoshi
2016-06-30
This presentation begins by describing RF superconductivity and SRF accelerating structures. Then the use of superconducting RF structures in a number of accelerators around the world is reviewed; for example, the International Linear Collider (ILC) will use ~16,000 SRF cavities with ~2,000 cryomodules to get 500 GeV e⁺/e⁻ colliding energy. Field emission control was (and still is) a very important practical issue for SRF cavity development. It has been found that high-pressure ultrapure water rinsing as a final cleaning step after chemical surface treatment resulted in consistent performance of single- and multicell superconducting cavities.
Commentary: The Materials Project: A materials genome approach to accelerating materials innovation
NASA Astrophysics Data System (ADS)
Jain, Anubhav; Ong, Shyue Ping; Hautier, Geoffroy; Chen, Wei; Richards, William Davidson; Dacek, Stephen; Cholia, Shreyas; Gunter, Dan; Skinner, David; Ceder, Gerbrand; Persson, Kristin A.
2013-07-01
Accelerating the discovery of advanced materials is essential for human welfare and sustainable, clean energy. In this paper, we introduce the Materials Project (www.materialsproject.org), a core program of the Materials Genome Initiative that uses high-throughput computing to uncover the properties of all known inorganic materials. This open dataset can be accessed through multiple channels for both interactive exploration and data mining. The Materials Project also seeks to create open-source platforms for developing robust, sophisticated materials analyses. Future efforts will enable users to perform ``rapid-prototyping'' of new materials in silico, and provide researchers with new avenues for cost-effective, data-driven materials design.
NASA Technical Reports Server (NTRS)
Barile, Ronald G.; Fogarty, Chris; Cantrell, Chris; Melton, Gregory S.
1994-01-01
NASA personnel at Kennedy Space Center's Material Science Laboratory have developed new environmentally sound precision cleaning and verification techniques for systems and components found at the center. This technology is required to replace existing methods traditionally employing CFC-113. The new patent-pending technique of precision cleaning verification is for large components of cryogenic fluid systems. These are stainless steel, sand cast valve bodies with internal surface areas ranging from 0.2 to 0.9 sq m. Extrapolation of this technique to components of even larger sizes (by orders of magnitude) is planned. Currently, the verification process is completely manual. In the new technique, a high velocity, low volume water stream impacts the part to be verified. This process is referred to as Breathing Air/Water Impingement and forms the basis for the Impingement Verification System (IVS). The system is unique in that a gas stream is used to accelerate the water droplets to high speeds. Water is injected into the gas stream in a small, continuous amount. The air/water mixture is then passed through a converging/diverging nozzle where the gas is accelerated to supersonic velocities. These droplets impart sufficient energy to the precision cleaned surface to place non-volatile residue (NVR) contaminants into suspension in the water. The sample water is collected and its NVR level is determined by total organic carbon (TOC) analysis at 880 C. The TOC, in ppm carbon, is used to establish the NVR level. A correlation between the present gravimetric CFC113 NVR and the IVS NVR is found from experimental sensitivity factors measured for various contaminants. The sensitivity has the units of ppm of carbon per mg/sq ft of contaminant. In this paper, the equipment is described and data are presented showing the development of the sensitivity factors from a test set including four NVRs impinged from witness plates of 0.05 to 0.75 sq m.
NASA Technical Reports Server (NTRS)
Barile, Ronald G.; Fogarty, Chris; Cantrell, Chris; Melton, Gregory S.
1995-01-01
NASA personnel at Kennedy Space Center's Material Science Laboratory have developed new environmentally sound precision cleaning and verification techniques for systems and components found at the center. This technology is required to replace existing methods traditionally employing CFC-113. The new patent-pending technique of precision cleaning verification is for large components of cryogenic fluid systems. These are stainless steel, sand cast valve bodies with internal surface areas ranging from 0.2 to 0.9 m(exp 2). Extrapolation of this technique to components of even larger sizes (by orders of magnitude) is planned. Currently, the verification process is completely manual. In the new technique, a high velocity, low volume water stream impacts the part to be verified. This process is referred to as Breathing Air/Water Impingement and forms the basis for the Impingement Verification System (IVS). The system is unique in that a gas stream is used to accelerate the water droplets to high speeds. Water is injected into the gas stream in a small, continuous amount. The air/water mixture is then passed through a converging-diverging nozzle where the gas is accelerated to supersonic velocities. These droplets impart sufficient energy to the precision cleaned surface to place non-volatile residue (NVR) contaminants into suspension in the water. The sample water is collected and its NVR level is determined by total organic carbon (TOC) analysis at 880 C. The TOC, in ppm carbon, is used to establish the NVR level. A correlation between the present gravimetric CFC-113 NVR and the IVS NVR is found from experimental sensitivity factors measured for various contaminants. The sensitivity has the units of ppm of carbon per mg-ft(exp 2) of contaminant. In this paper, the equipment is described and data are presented showing the development of the sensitivity factors from a test set including four NVR's impinged from witness plates of 0.05 to 0.75 m(exp 2).
In Situ Oxalic Acid Injection to Accelerate Arsenic Remediation at a Superfund Site in New Jersey.
Wovkulich, Karen; Stute, Martin; Mailloux, Brian J; Keimowitz, Alison R; Ross, James; Bostick, Benjamin; Sun, Jing; Chillrud, Steven N
2014-09-25
Arsenic is a prevalent contaminant at a large number of US Superfund sites; establishing techniques that accelerate As remediation could benefit many sites. Hundreds of tons of As were released into the environment by the Vineland Chemical Co. in southern New Jersey during its manufacturing lifetime (1949-1994), resulting in extensive contamination of surface and subsurface soils and sediments, groundwater, and the downstream watershed. Despite substantial intervention at this Superfund site, sufficient aquifer cleanup could require many decades if based on traditional pump and treat technologies only. Laboratory column experiments have suggested that oxalic acid addition to contaminated aquifer solids could promote significant As release from the solid phase. To evaluate the potential of chemical additions to increase As release in situ and boost treatment efficiency, a forced gradient pilot scale study was conducted on the Vineland site. During spring/summer 2009, oxalic acid and bromide tracer were injected into a small portion (~50 m 2 ) of the site for 3 months. Groundwater samples indicate that introduction of oxalic acid led to increased As release. Between 2.9 and 3.6 kg of As were removed from the sampled wells as a result of the oxalic acid treatment during the 3-month injection. A comparison of As concentrations on sediment cores collected before and after treatment and analyzed using X-ray fluorescence spectroscopy suggested reduction in As concentrations of ~36% (median difference) to 48% (mean difference). While further study is necessary, the addition of oxalic acid shows potential for accelerating treatment of a highly contaminated site and decreasing the As remediation time-scale.
Shallow, non-pumped wells: a low-energy alternative for cleaning polluted groundwater.
Hudak, Paul F
2013-07-01
This modeling study evaluated the capability of non-pumped wells with filter media for preventing contaminant plumes from migrating offsite. Linear configurations of non-pumped wells were compared to permeable reactive barriers in simulated shallow homogeneous and heterogeneous aquifers. While permeable reactive barriers enabled faster contaminant removal and shorter distances of contaminant travel, non-pumped wells also prevented offsite contaminant migration. Overall, results of this study suggest that discontinuous, linear configurations of non-pumped wells may be a viable alternative to much more costly permeable reactive barriers for preventing offsite contaminant travel in some shallow aquifers.
Management of Munitions Constituents in Soil Using Alkaline Hydrolysis: A Practical Guide
2011-05-12
to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202...Induced Transformation of Explosives Dissolved Hydroxide Clean water to groundwater Lime Addition W at er M ov em en t Soluble lime moving with...0.995 Ti m e Reaction Time (hr) 0 5 10 15 20 25 TN T C on ce nt ra tio n (m g/ L) 0 1 2 3 4 5 6 7 Time 0 2 4 6 8 10 12 14 16 D et ec to r R es po
1988-11-01
paint chips at the sampling site. 0 Clean water tanks, pumps, mud pans, hoses, including hoses and tanks used to transfer water from source to drill rig...TO’ LCA , Filll I F’APCr,;I~- € C/ " rKL2PIrlA , ATTFNrIGN TO SMOKING. ALCOHOLF MFDrICATIONP AND FXPOSI.RE TO CARCINOGENS.1 ENERAL MEDICAl. HISTORY...A. General: 1. Place samples in core trough for visual inspection. After logging, place selected samples in sample jars or wood core boxes. 2. Seal
Tandem accelerators in Romania: Multi-tools for science, education and technology
NASA Astrophysics Data System (ADS)
Burducea, I.; GhiÅ£ǎ, D. G.; Sava, T. B.; Straticiuc, M.
2017-06-01
An educated selection of the main beam parameters - particle type, velocity and intensity, can result in a cutting-edge scalpel to remove tumors, sanitize sewage, act as a nuclear forensics detective, date an artefact, clean up air, improve a microprocessor, transmute nuclear waste, detect a counterfeit or even look into the stars. Nowadays more than particle accelerators operate worldwide in medicine, industry and basic research. For example the proton therapy market is expected to attain 1 billion US per year in 2019 with almost 330 proton therapy rooms, while the annual market for the ion implantation industry already reached 1.5 G in revenue [1,2]. A brief history of the Tandem Accelerators Complex at IFIN-HH [3] emphasizing on their applications and the physics behind the scenes, is also presented [4-6].
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cuneo, M.E.; Menge, P.R.; Hanson, D.L.
Application of ion beams to Inertial Confinement Fusion requires efficient production, transport and focusing of an intense, low microdivergence beam of an appropriate range ion. At Sandia, the authors are studying the production of lithium ion beams in extraction applied-B ion diodes on the SABRE accelerator (5 MV, 250 kA). Evidence on both SABRE (1 TW) and PBFA-II (20 TW) indicates that the lithium beam turns off and is replaced by a beam of mostly protons and carbon, possibly due to electron thermal and stimulated desorption of hydrocarbon surface contamination with subsequent avalanche ionization. Turn-off of the lithium beam ismore » accompanied by rapid impedance collapse. Surface cleaning techniques are being developed to reduce beam contamination, increase the total lithium energy and reduce the rate of diode impedance collapse. Application of surface cleaning techniques has increased the production of lithium from passive LiF sources by a factor of 2. Improved diode electric and magnetic field profiles have increased the diode efficiency and production of lithium by a factor of 5, without surface cleaning. Work is ongoing to combine these two advances which are discussed here.« less
The accelerated site technology deployment program presents the segmented gate system
DOE Office of Scientific and Technical Information (OSTI.GOV)
PATTESON,RAYMOND; MAYNOR,DOUG; CALLAN,CONNIE
2000-02-24
The Department of Energy (DOE) is working to accelerate the acceptance and application of innovative technologies that improve the way the nation manages its environmental remediation problems. The DOE Office of Science and Technology established the Accelerated Site Technology Deployment Program (ASTD) to help accelerate the acceptance and implementation of new and innovative soil and ground water remediation technologies. Coordinated by the Department of Energy's Idaho Office, the ASTD Program reduces many of the classic barriers to the deployment of new technologies by involving government, industry, and regulatory agencies in the assessment, implementation, and validation of innovative technologies. The papermore » uses the example of the Segmented Gate System (SGS) to illustrate how the ASTD program works. The SGS was used to cost effectively separate clean and contaminated soil for four different radionuclides: plutonium, uranium, thorium, and cesium. Based on those results, it has been proposed to use the SGS at seven other DOE sites across the country.« less
Land subsidence in the San Joaquin Valley, California, USA, 2007-14
Sneed, Michelle; Brandt, Justin
2015-01-01
Rapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater pumping, groundwater-level declines, and land subsidence. Differential land subsidence has reduced the flow capacity of water-conveyance systems in these areas, exacerbating flood hazards and affecting the delivery of irrigation water. Vertical land-surface changes during 2007–2014 were determined by using Interferometric Synthetic Aperture Radar (InSAR), Continuous Global Positioning System (CGPS), and extensometer data. Results of the InSAR analysis indicate that about 7600 km2 subsided 50–540 mm during 2008–2010; CGPS and extensometer data indicate that these rates continued or accelerated through December 2014. The maximum InSAR-measured rate of 270 mm yr−1 occurred in the El Nido area, and is among the largest rates ever measured in the SJV. In the Pixley area, the maximum InSAR-measured rate during 2008–2010 was 90 mm yr−1. Groundwater was an important part of the water supply in both areas, and pumping increased when land use changed or when surface water was less available. This increased pumping caused groundwater-level declines to near or below historical lows during the drought periods 2007–2009 and 2012–present. Long-term groundwater-level and land-subsidence monitoring in the SJV is critical for understanding the interconnection of land use, groundwater levels, and subsidence, and evaluating management strategies that help mitigate subsidence hazards to infrastructure while optimizing water supplies.
NASA Astrophysics Data System (ADS)
Siebert, Christian; Broder, Merkel; Thomas, Pohl; Yossi, Yechieli; Eldat, Hazan; Danny, Ionescu; Ulf, Mallast
2017-04-01
Along the coastline of the hyper-saline and dramatically dropping Dead Sea, fresh to highly saline groundwaters discharge abundantly from dry falling lakebed. During its history, the level and hence salinity of the lake strongly fluctuated, resulting in the deposition of an alternating sequence of clayey and chemical sediments (mainly halite, carbonates and sulfates), intercalated by thick beds of halite and of coarse clastics around wadi outlets, respectively. Due to the asymmetrical shape of the lake's basin, these strata are deposited unequally along the eastern and western flank, why only groundwaters coming from the west have to pass thick layers of these sediments on their way into the lake. On the base of trace elements (REE), element ratios, stable and radioisotopes and microbiological findings, the observed onshore and offshore springs revealed, freshwaters discharge from both Cretaceous limestone aquifers and efficiently dissolve the easily soluble halite and flush the interstitial brines from the saliferous clay formation, immediately after entering the sedimentary strata. Abundant microbial activity result in the widespread production of sulfuric acid, accelerating erosion of carbonates and sulfates. These processes result in a fast and striking karstification of the strata, enabling groundwaters to transcendent the fresh/saltwater interface trough open pipes. As results, submarine groundwater discharge (SGD) occurs randomly and in addition to terrestrial, submarine sinkholes develop very quickly too. Due to the variable maturity of the flow paths, salinity and chemical composition of SGD shows an extremely wide range, from potable water to TDS of >250 g/l. Submarine emerging groundwaters with salinities even higher then that of the Dead Sea and distinctly different chemical and isotopic composition form outlets, which are not known elsewhere and represent a novel and unique type of SGD, only observed in the Dead Sea yet.
Farooq, S H; Chandrasekharam, D; Berner, Z; Norra, S; Stüben, D
2010-11-01
In the wake of the idea that surface derived dissolved organic carbon (DOC) plays an important role in the mobilization of arsenic (As) from sediments to groundwater and may provide a vital tool in understanding the mechanism of As contamination (mobilization/fixation) in Bengal delta; a study has been carried out. Agricultural fields that mainly cultivate rice (paddy fields) leave significantly large quantities of organic matter/organic carbon on the surface of Bengal delta which during monsoon starts decomposing and produces DOC. The DOC thus produced percolates down with rain water and mobilizes As from the sediments. Investigations on sediment samples collected from a paddy field clearly indicate that As coming on to the surface along with the irrigation water accumulates itself in the top few meters of sediment profile. The column experiments carried out on a 9 m deep sediment profile demonstrates that DOC has a strong potential to mobilize As from the paddy fields and the water recharging the aquifer through such agricultural fields contain As well above the WHO limit thus contaminating the shallow groundwater. Experiment also demonstrates that decay of organic matter induces reducing condition in the sediments. Progressively increasing reducing conditions not only prevent the adsorption of As on mineral surfaces but also cause mobilization of previously sorbed arsenic. There seems to be a cyclic pattern where As from deeper levels comes to the surface with irrigational water, accumulates itself in the sediments, and ultimately moves down to the shallow groundwater. The extensive and continual exploitation of intermediate/deep groundwater accelerates this cyclic process and helps in the movement of shallow contaminated groundwater to the deeper levels. Copyright © 2010 Elsevier Ltd. All rights reserved.
Energy by the Numbers: An Energy Revolution
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
The U.S. Department of Energy (DOE) today released a new report that highlights the accelerated deployment of five clean energy technologies: wind turbines, solar technologies for both utility-scale and distributed photovoltaic (PV), electric vehicles (EVs) and light-emitting diodes (LEDs). The report, Revolution…Now, was announced by Energy Secretary Ernest Moniz during a discussion at The Atlantic’s Washington Ideas Forum.
Ultrasonic Mastering of Filter Flow and Antifouling of Renewable Resources.
Radziuk, Darya; Möhwald, Helmuth
2016-04-04
Inadequate access to pure water and sanitation requires new cost-effective, ergonomic methods with less consumption of energy and chemicals, leaving the environment cleaner and sustainable. Among such methods, ultrasound is a unique means to control the physics and chemistry of complex fluids (wastewater) with excellent performance regarding mass transfer, cleaning, and disinfection. In membrane filtration processes, it overcomes diffusion limits and can accelerate the fluid flow towards the filter preventing antifouling. Here, we outline the current state of knowledge and technological design, with a focus on physicochemical strategies of ultrasound for water cleaning. We highlight important parameters of ultrasound for the delivery of a fluid flow from a technical perspective employing principles of physics and chemistry. By introducing various ultrasonic methods, involving bubbles or cavitation in combination with external fields, we show advancements in flow acceleration and mass transportation to the filter. In most cases we emphasize the main role of streaming and the impact of cavitation with a perspective to prevent and remove fouling deposits during the flow. We also elaborate on the deficiencies of present technologies and on problems to be solved to achieve a wide-spread application. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zhu, Minghua; Zhao, Hongxia; Xia, Deming; Du, Juan; Xie, Huaijun; Chen, Jingwen
2018-08-30
An accelerated solvent extraction (ASE) with in-cell clean-up method coupled to ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to determine 21 antibiotics in sea cucumber. The analytes include 10 sulfonamides, 4 fluoroquinolones, 3 amphenicols, 2 beta-lactams, 1 lincosamide and trimethoprim. Optimal parameters of ASE method were obtained at 80 °C, 1 static cycle of 5 min with methanol/acetonitrile (1/1, v/v) using 2 g of C18 as adsorbent. Recoveries at 50.1-129.2% were achieved with RSD under 20%. Method detection limits ranged from 0.03 to 2.9 μg kg -1 . Compared to the reported ultrasound-assisted extraction method, the proposed method offered comparable extraction efficiency for sulfonamides from sea cucumber, but higher for other categories of antibiotics. This validated method was then successfully applied to sea cucumber samples and 9 antibiotics were detected with the highest concentration up to 57.7 μg kg -1 for norfloxacin. Copyright © 2018 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zurek, A. J.; Witczak, S.; Dulinski, M.; Wachniew, P.; Rozanski, K.; Kania, J.; Postawa, A.; Karczewski, J.; Moscicki, W. J.
2015-02-01
Groundwater-dependent ecosystems (GDEs) have important functions in all climatic zones as they contribute to biological and landscape diversity and provide important economic and social services. Steadily growing anthropogenic pressure on groundwater resources creates a conflict situation between nature and man which are competing for clean and safe sources of water. Such conflicts are particularly noticeable in GDEs located in densely populated regions. A dedicated study was launched in 2010 with the main aim to better understand the functioning of a groundwater-dependent terrestrial ecosystem (GDTE) located in southern Poland. The GDTE consists of a valuable forest stand (Niepolomice Forest) and associated wetland (Wielkie Błoto fen). It relies mostly on groundwater from the shallow Quaternary aquifer and possibly from the deeper Neogene (Bogucice Sands) aquifer. In July 2009 a cluster of new pumping wells abstracting water from the Neogene aquifer was set up 1 km to the northern border of the fen. A conceptual model of the Wielkie Błoto fen area for the natural, pre-exploitation state and for the envisaged future status resulting from intense abstraction of groundwater through the new well field was developed. The main aim of the reported study was to probe the validity of the conceptual model and to quantify the expected anthropogenic impact on the studied GDTE. A wide range of research tools was used. The results obtained through combined geologic, geophysical, geochemical, hydrometric and isotope investigations provide strong evidence for the existence of upward seepage of groundwater from the deeper Neogene aquifer to the shallow Quaternary aquifer supporting the studied GDTE. Simulations of the groundwater flow field in the study area with the aid of a 3-D flow and transport model developed for Bogucice Sands (Neogene) aquifer and calibrated using environmental tracer data and observations of hydraulic head in three different locations on the study area, allowed us to quantify the transient response of the aquifer to operation of the newly established Wola Batorska well field. The model runs reveal the presence of upward groundwater seepage to the shallow Quaternary aquifer of the order of 440 m3 d-1. By the end of the simulation period (2029), with continuous operation of the Wola Batorska well field at maximum permissible capacity (ca. 10 000 m3 d-1), the direction of groundwater seepage will change sign (total change of the order of 900 m3 d-1). The water table drawdown in the study area will reach ca. 30 cm. This may have significant adverse effects on functioning of the studied GDTE.
Innovative Commercialization Efforts Underway at the National Renewable Energy Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheesbrough, Kate; Bader, Meghan
New clean energy and energy efficiency technology solutions hold the promise of significant reductions in energy consumption. However, proven barriers for these technologies, including the technological and commercialization valleys of death, result in promising technologies falling to the wayside. To address these gaps, NREL's Innovation & Entrepreneurship Center designs and manages advanced programs aimed at supporting the development and commercialization of early stage clean energy technologies with the goal of accelerating new technologies to market. These include: Innovation Incubator (IN2) in partnership with Wells Fargo: this technology incubator supports energy efficiency building-related startups to overcome market gaps by providing accessmore » to technical support at NREL; Small Business Voucher Pilot: this program offers paid vouchers for applicants to access a unique skill, capability, or facility at any of the 17 DOE National Laboratories to bring next-generation clean energy technologies to market; Energy Innovation Portal: NREL designed and developed the Energy Innovation Portal, providing access to EERE focused intellectual property available for licensing from all of the DOE National Laboratories; Lab-Corps: Lab-Corps aims to better train and empower national lab researchers to understand market drivers and successfully transition their discoveries into high-impact, real world technologies in the private sector; Incubatenergy Network: the Network provides nationwide coordination of clean energy business incubators, share best practices, support clean energy entrepreneurs, and help facilitate a smoother transition to a more sustainable clean energy economy; Industry Growth Forum: the Forum is the perfect venue for clean energy innovators to maximize their exposure to receptive capital and strategic partners. Since 2003, presenting companies have collectively raised more than $5 billion in growth financing.« less
Landslide triggering by rain infiltration
Iverson, Richard M.
2000-01-01
Landsliding in response to rainfall involves physical processes that operate on disparate timescales. Relationships between these timescales guide development of a mathematical model that uses reduced forms of Richards equation to evaluate effects of rainfall infiltration on landslide occurrence, timing, depth, and acceleration in diverse situations. The longest pertinent timescale is A/D0, where D0 is the maximum hydraulic diffusivity of the soil and A is the catchment area that potentially affects groundwater pressures at a prospective landslide slip surface location with areal coordinates x, y and depth H. Times greater than A/D0 are necessary for establishment of steady background water pressures that develop at (x, y, H) in response to rainfall averaged over periods that commonly range from days to many decades. These steady groundwater pressures influence the propensity for landsliding at (x, y, H), but they do not trigger slope failure. Failure results from rainfall over a typically shorter timescale H2/D0 associated with transient pore pressure transmission during and following storms. Commonly, this timescale ranges from minutes to months. The shortest timescale affecting landslide responses to rainfall is √(H/g), where g is the magnitude of gravitational acceleration. Postfailure landslide motion occurs on this timescale, which indicates that the thinnest landslides accelerate most quickly if all other factors are constant. Effects of hydrologic processes on landslide processes across these diverse timescales are encapsulated by a response function, R(t*) = √(t*/π) exp (-1/t*) - erfc (1/√t*), which depends only on normalized time, t*. Use of R(t*) in conjunction with topographic data, rainfall intensity and duration information, an infinite-slope failure criterion, and Newton's second law predicts the timing, depth, and acceleration of rainfall-triggered landslides. Data from contrasting landslides that exhibit rapid, shallow motion and slow, deep-seated motion corroborate these predictions.
Peter Caldwell; Chelcy F. Miniat; Doug Aubrey; Rhett Jackson; Jeff McDonnell; Ken W. Krauss; James S. Latimer
2016-01-01
The southern United States is a potential leader in producing biofuels from intensively managed, short rotation (8â12 years) woody crops such as southern pines, and native and non-native hardwoods. However, their accelerated development under intensive management has raised concerns that fast-growing bioenergy crops could reduce recharge to stream flows and groundwater...
NASA Astrophysics Data System (ADS)
Zachara, J. M.
2009-12-01
The Hanford Integrated Field Research Challenge (IFRC) site is a DOE/BER-supported experimental and monitoring facility focused on multi-scale mass transfer processes (hanfordifc@pnl.gov). It is located within the footprint of a historic uranium (U) waste disposal pond that overlies a contaminated vadose zone and a 1 km+ groundwater U plume. The plume is under a regulatory clean-up mandate. The site is in hydraulic connectivity with the Columbia River that is located approximately 300 m distant. Dramatic seasonal variations in Columbia River stage cause 2m+ variations in water table and associated changes in groundwater flow directions and composition that are believed to recharge contaminant U to the plume through lower vadose zone pumping. The 60 m triangular shaped facility contains 37 monitoring wells equipped with down-hole electrical resistance tomography electrode and thermistor arrays, pressure transducers for continual water level monitoring, and specific conductance electrodes. Well spacings allow cross-hole geophysical interrogation and dynamic plume monitoring. Various geophysical and hydrologic field characterizations were performed during and after well installation, and retrieved sediments are being subjected to a hierarchal laboratory characterization process to support geostatistical models of hydrologic properties, U(VI) distribution and speciation, and equilibrium and kinetic reaction parameters for robust but tractable field-scale reactive transport calculations. Three large scale (10,000 gal+), non-reactive tracer experiments have been performed to evaluate groundwater flowpaths and velocities, facies scale mass transfer, and subsurface heterogeneity effects under different hydrologic conditions (e.g., flow vectors toward or away from the river). A passive monitoring experiment was completed during spring and summer of 2009 that documents spatially variable U(VI) release and plume recharge from the contaminated lower vadose zone during oscillating rising and falling water table events. A large scale injection experiment to evaluate in situ U(VI) desorption kinetics controlled by mass transfer is planned for the fall of 2009. The presentation will summarize key results from these different activities, and discuss their implications to improved plume forecasting and development of an effective groundwater remedy.
NASA Astrophysics Data System (ADS)
Clapp, L. W.; Cabezas, J.; Gamboa, Y.; Fernandez, W.
2011-12-01
State and federal regulations require that groundwater at in-situ recovery (ISR) uranium mining operations be restored to pre-mining conditions. Reverse osmosis (RO) filtration of several pore volumes of the post-leached groundwater and reinjection of the clean permeate is the most common technology currently used for restoring groundwater at uranium ISR sites. However, this approach does not revert the formation back to its initial reducing conditions, which can potentially impede timely groundwater restoration. In-situ biostimulation of indigenous iron- and sulfate reducing bacteria by injection of organic electron donors (e.g., ethanol, acetate, and lactate) to promote soluble uranium reduction and immobilization has been the subject of previous studies. However, injection of organic substrates has been observed to cause aquifer clogging near the injection point. In addition, U(VI) solubility may be enhanced through complexation with carbonate generated by organic carbon oxidation. An alternative approach that may overcome these problems involves the use of hydrogen as a reductant to promote microbial reduction and immobilization of U(VI) in situ. To test this approach, approximately 100,000 scf of compressed hydrogen gas was injected into a leached unconsolidated sand zone over two months at an ISR mining site. During this time groundwater was recirculated between injection and extraction wells (separated by 130 ft) at a rate of about 40 gpm and bromide was coinjected as a conservative tracer. A well monitoring program has been executed since June 2009 to evaluate the performance of the hydrogen injection. Current results show that U(VI) has been reduced from 4.2 to 0.05 ppm in the area surrounding the injection well and to 2.0 ± 0.3 ppm in the area surrounding the extraction well and two intermediate monitoring wells. Other water quality changes near the injection well include significant decreases in concentrations of Mo, sulfate, Fe, Mn, bicarbonate, Ca, and Eh, and increases in pH, methane, and sulfide. No significant rebound of soluble uranium concentrations was observed, but significant rebounds in molybdenum and sulfate have been observed. Ongoing studies are evaluating the effective zone of influence of the hydrogen injection.
NASA Astrophysics Data System (ADS)
Pierce, S. A.
2017-12-01
Decision making for groundwater systems is becoming increasingly important, as shifting water demands increasingly impact aquifers. As buffer systems, aquifers provide room for resilient responses and augment the actual timeframe for hydrological response. Yet the pace impacts, climate shifts, and degradation of water resources is accelerating. To meet these new drivers, groundwater science is transitioning toward the emerging field of Integrated Water Resources Management, or IWRM. IWRM incorporates a broad array of dimensions, methods, and tools to address problems that tend to be complex. Computational tools and accessible cyberinfrastructure (CI) are needed to cross the chasm between science and society. Fortunately cloud computing environments, such as the new Jetstream system, are evolving rapidly. While still targeting scientific user groups systems such as, Jetstream, offer configurable cyberinfrastructure to enable interactive computing and data analysis resources on demand. The web-based interfaces allow researchers to rapidly customize virtual machines, modify computing architecture and increase the usability and access for broader audiences to advanced compute environments. The result enables dexterous configurations and opening up opportunities for IWRM modelers to expand the reach of analyses, number of case studies, and quality of engagement with stakeholders and decision makers. The acute need to identify improved IWRM solutions paired with advanced computational resources refocuses the attention of IWRM researchers on applications, workflows, and intelligent systems that are capable of accelerating progress. IWRM must address key drivers of community concern, implement transdisciplinary methodologies, adapt and apply decision support tools in order to effectively support decisions about groundwater resource management. This presentation will provide an overview of advanced computing services in the cloud using integrated groundwater management case studies to highlight how Cloud CI streamlines the process for setting up an interactive decision support system. Moreover, advances in artificial intelligence offer new techniques for old problems from integrating data to adaptive sensing or from interactive dashboards to optimizing multi-attribute problems. The combination of scientific expertise, flexible cloud computing solutions, and intelligent systems opens new research horizons.
Spatial and temporal variation of denitrification in the riparian zone during the hydrological year
NASA Astrophysics Data System (ADS)
Trauth, Nico; Musolff, Andreas; Knöller, Kay; Fleckenstein, Jan H.
2017-04-01
In the riparian zone, where stream water mixes with groundwater, biogeochemical reactions and solute transformations occur which may enhance the self-cleaning mechanisms of aquatic ecosystems. The water exchange and solute transport through the riparian zone is controlled by hydraulic gradients between stream and groundwater and thus varies seasonally and during stream discharge events. In this study, we focus on transport, mixing and the distribution of nitrate in the riparian zone of a gravelly alluvial aquifer with the aim to quantify its denitrification potential during the hydrological year. For this purpose, 25 groundwater wells were drilled along a 2 km stream section of the Selke river, a third-order stream in Germany. From the stream and the wells, water samples were taken 4-weekly over a period of 2 years. Water samples were analyzed to field parameters, major ions, dissolved organic carbon, and N-O isotopes. Results show a strong influence of the stream on the adjacent groundwater, which varies both in time and space. In general, we can distinguish between two endmembers: a) the stream water with low chloride (<30 mg/L) and nitrate (<10 mg/L) concentrations and b) the groundwater in 100m distance to the stream with high chloride (>70 mg/L) and nitrate (>50 mg/L) concentrations. Based on conservatively transported chloride, the mixing of the endmembers can be determined in the riparian zone. Deviations in nitrate concentrations from this mixing model may indicate nitrate degradation by e.g. denitrification. By combining this chloride-nitrate-ratio method with dissolved oxygen data and the isotopic signature of the nitrate molecule, we are able to determine the timing and the location of high denitrification patterns in the riparian aquifer. Highest variability of denitrification occurs over the year in terms of seasonality (temperature-driven) and is temporally fueled by additional organic carbon supply during discharge events.
Seasonal arsenic accumulation in stream sediments at a groundwater discharge zone.
MacKay, Allison A; Gan, Ping; Yu, Ran; Smets, Barth F
2014-01-21
Seasonal changes in arsenic and iron accumulation rates were examined in the sediments of a brook that receives groundwater discharges of arsenic and reduced iron. Clean glass bead columns were deployed in sediments for known periods over the annual hydrologic cycle to monitor changes in arsenic and iron concentrations in bead coatings. The highest accumulation rates occurred during the dry summer period (July-October) when groundwater discharges were likely greatest at the sample locations. The intermediate flow period (October-March), with higher surface water levels, was associated with losses of arsenic and iron from bead column coatings at depths below 2-6 cm. Batch incubations indicated iron releases from solids to be induced by biological reduction of iron (oxy)hydroxide solids. Congruent arsenic releases during incubation were limited by the high arsenic sorption capacity (0.536 mg(As)/mg(Fe)) of unreacted iron oxide solids. The flooded spring (March-June) with high surface water flows showed the lowest arsenic and iron accumulation rates in the sediments. Comparisons of accumulation rates across a shoreline transect were consistent with greater rates at regions exposed above surface water levels for longer times and greater losses at locations submerged below surface water. Iron (oxy)hydroxide solids in the shallowest sediments likely serve as a passive barrier to sorb arsenic released to pore water at depth by biological iron reduction.
Key NASA, USAF and federal officials sign a Memorandum of Agreement on groundwater cleanup
NASA Technical Reports Server (NTRS)
1999-01-01
Key participants in the signing of a Memorandum of Agreement, formalizing cooperative efforts of NASA, the U.S. Air Force, and federal agencies in ground-water cleanup initiatives, gather on top of the block house at Launch Complex 34. Motioning at right is Skip Chamberlain, program manager, Office of Science and Technology, U.S. Department of Energy. Others on the tour include Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; Roy Bridges Jr., director of John F. Kennedy Space Center; Walter Kovalick Jr., Ph.D., director, Technology Innovation Office, U.S. Environmental Protection Agency. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally.
Bacterial Diversity in Submarine Groundwater along the Coasts of the Yellow Sea
Ye, Qi; Liu, Jianan; Du, Jinzhou; Zhang, Jing
2016-01-01
Submarine groundwater (SGD) is one of the most significant pathways for the exchange of groundwater and/or source of nutrients, metals and carbon to the ocean, subsequently cause deleterious impacts on the coastal ecosystems. Microorganisms have been recognized as the important participators in the biogeochemical processes in the SGD. In this study, by utilizing 16S rRNA-based Illumina Miseq sequencing technology, we investigated bacterial diversity and distribution in both fresh well water and brackish recirculated porewater along the coasts in the Yellow Sea. The results showed that Actinobacteria and Betaproteobacteria, especially Comamonas spp. and Limnohabitans spp. were dominated in fresh well samples. Distinct patterns of bacterial communities were found among the porewater samples due to different locations, for examples, Cyanbacteria was the most abundant in the porewater samples far from the algal bloomed areas. The analysis of correlation between representative bacterial taxonomic groups and the contexture environmental parameters showed that fresh well water and brackish porewater might provide different nutrients to the coastal waters. Potential key bacterial groups such as Comamonas spp. may be excellent candidates for the bioremediation of the natural pollutants in the SGD. Our comprehensive understanding of bacterial diversity in the SGD along the coasts of the Yellow Sea will create a basis for designing the effective clean-up approach in-situ, and provide valuable information for the coastal management. PMID:26779172
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
Hazardous chemicals in the environment have received ever increasing attention in recent years. In response to ongoing problems with hazardous waste management, Congress enacted the Resource Conservation and Recovery Act (RCRA) in 1976. In 1980, Congress adopted the Comprehensive Environmental Response Compensation, and Liability Act (CERCLA), commonly called Superfund to provide for emergency spill response and to clean up closed or inactive hazardous waste sites. Scientists and engineers have begun to respond to the hazardous waste challenge with research and development on treatment of waste streams as well as cleanup of polluted areas. The magnitude of the problem is justmore » now beginning to be understood. The U.S. Environmental Protection Agency (USEPA) National Priorities List as of September 13 1985, contained 318 proposed sites and 541 final sites (USEPA, 1985). Estimates of up to 30,000 sites containing hazardous wastes (1,200 to 2,000 of which present a serious threat to public health) have been made (Public Law 96-150). In addition to the large number of sites, the costs of cleanup using available technology are phenomenal. For example, a 10-acre toxic waste site in Ohio is to be cleaned up by removing chemicals from the site and treating the contaminated groundwater. The federal government has already spent more than $7 million to remove the most hazardous wastes and the groundwater decontamination alone is expected to take at least 10 years and cost $12 million. Another example of cleanup costs comes from the State of California Commission for Economic Development which predicts a bright economic future for the state except for the potential outlay of $40 billion for hazardous waste cleanup mandated by federal and state laws.« less
Programming and Runtime Support to Blaze FPGA Accelerator Deployment at Datacenter Scale
Huang, Muhuan; Wu, Di; Yu, Cody Hao; Fang, Zhenman; Interlandi, Matteo; Condie, Tyson; Cong, Jason
2017-01-01
With the end of CPU core scaling due to dark silicon limitations, customized accelerators on FPGAs have gained increased attention in modern datacenters due to their lower power, high performance and energy efficiency. Evidenced by Microsoft’s FPGA deployment in its Bing search engine and Intel’s 16.7 billion acquisition of Altera, integrating FPGAs into datacenters is considered one of the most promising approaches to sustain future datacenter growth. However, it is quite challenging for existing big data computing systems—like Apache Spark and Hadoop—to access the performance and energy benefits of FPGA accelerators. In this paper we design and implement Blaze to provide programming and runtime support for enabling easy and efficient deployments of FPGA accelerators in datacenters. In particular, Blaze abstracts FPGA accelerators as a service (FaaS) and provides a set of clean programming APIs for big data processing applications to easily utilize those accelerators. Our Blaze runtime implements an FaaS framework to efficiently share FPGA accelerators among multiple heterogeneous threads on a single node, and extends Hadoop YARN with accelerator-centric scheduling to efficiently share them among multiple computing tasks in the cluster. Experimental results using four representative big data applications demonstrate that Blaze greatly reduces the programming efforts to access FPGA accelerators in systems like Apache Spark and YARN, and improves the system throughput by 1.7 × to 3× (and energy efficiency by 1.5× to 2.7×) compared to a conventional CPU-only cluster. PMID:28317049
Programming and Runtime Support to Blaze FPGA Accelerator Deployment at Datacenter Scale.
Huang, Muhuan; Wu, Di; Yu, Cody Hao; Fang, Zhenman; Interlandi, Matteo; Condie, Tyson; Cong, Jason
2016-10-01
With the end of CPU core scaling due to dark silicon limitations, customized accelerators on FPGAs have gained increased attention in modern datacenters due to their lower power, high performance and energy efficiency. Evidenced by Microsoft's FPGA deployment in its Bing search engine and Intel's 16.7 billion acquisition of Altera, integrating FPGAs into datacenters is considered one of the most promising approaches to sustain future datacenter growth. However, it is quite challenging for existing big data computing systems-like Apache Spark and Hadoop-to access the performance and energy benefits of FPGA accelerators. In this paper we design and implement Blaze to provide programming and runtime support for enabling easy and efficient deployments of FPGA accelerators in datacenters. In particular, Blaze abstracts FPGA accelerators as a service (FaaS) and provides a set of clean programming APIs for big data processing applications to easily utilize those accelerators. Our Blaze runtime implements an FaaS framework to efficiently share FPGA accelerators among multiple heterogeneous threads on a single node, and extends Hadoop YARN with accelerator-centric scheduling to efficiently share them among multiple computing tasks in the cluster. Experimental results using four representative big data applications demonstrate that Blaze greatly reduces the programming efforts to access FPGA accelerators in systems like Apache Spark and YARN, and improves the system throughput by 1.7 × to 3× (and energy efficiency by 1.5× to 2.7×) compared to a conventional CPU-only cluster.
NASA Astrophysics Data System (ADS)
Edwards, E.; Harter, T.; Fogg, G. E.; Washburn, B.; Bryson, R.; Meirovitz, C.; Fawcett, J.; Kretsinger Grabert, V. J.; Bowles, C.; Carr, M.; Nelson, C.
2014-12-01
Dry wells are gravity-fed, excavated pits with perforated casings used to facilitate stormwater infiltration and groundwater recharge in areas comprised primarily of impermeable surfaces or low permeability soils. Stormwater runoff that would otherwise be routed to streams or drains in urban areas is used as a source of aquifer recharge. However, the potential for groundwater contamination caused by urban runoff bypassing surface soil filtration has prevented more widespread use of dry wells as a recharge mechanism. We present the results of a literature survey to assess the potential of dry wells for safe stormwater recharge. Dry wells have been inculpated in groundwater contamination events, although accusations were typically not backed by scientific data. In 1989 groundwater in Modesto, CA, was contaminated with tetrachloroethylene from a dry cleaning facility. The city had been using dry wells to manage stormwater for more than 50 years without detrimental impacts before the contamination. A USGS monitoring study proved that the contamination was from sewer system leakage, and did not involve the dry wells. Some areas of the country have used dry wells with positive results. The Underground Injection Control system (UICs) study in Portland, OR, has been active for ten years, and currently operates over 9,000 UICs. Initially, a ten foot separation distance was enforced between the seasonal high water table and the bottom perforation of the UIC; however, due to monitoring and modeling results that indicate the protectiveness of groundwater, this distance has been reduced to zero feet. Future work will include a comparative pilot study involving a residential and an industrial site in Elk Grove, CA. The study will use modeling tools to assess the recharge potential and groundwater protectiveness of dry wells. Both sites are outfitted with four monitoring wells each: an upgradient monitoring well, two downgradient monitoring wells, and a vadose zone monitoring well. The results of water quality sampling will determine the contaminants of interest, and a model of the fate and transport of these contaminants in the vadose zone will be coupled with hydraulic models to estimate the response of the hydrogeologic system to dry well recharge, with the goal of creating a tool that can be used to evaluate future dry well locations.
NASA Astrophysics Data System (ADS)
Belitz, K.
2015-12-01
What is the value of clean groundwater? Might one aquifer be considered more valuable than another? To help address these, and similar, questions, we propose that aquifers be assessed by two metrics: 1) the contaminated area of an aquifer, defined by high concentrations (km2 or proportion); and 2) equivalent-population potentially impacted by that contamination (number of people or proportion). Concentrations are considered high if they are above a human health benchmark. The two metrics provide a quantitative basis for assessment at the aquifer scale, rather than the well scale. This approach has been applied to groundwater used for public supply in California (Belitz and others, 2015). The assessment distinguishes between population (34 million, 2000 census) and equivalent-population (11 million) because public drinking water supplies can be a mix of surface water and groundwater. The assessment was conducted in 87 study areas which account for nearly 100% of the groundwater used for public supply. The area-metric, when expressed as a proportion, is useful for identifying where a particular contaminant or class of contaminants might be a cause for concern. In CA, there are 38 study where the area-metric ≥ 25% for one or more contaminants; in 7 of these, the area-metric ≥ 50%. Naturally-occurring trace elements, such as arsenic and uranium, are the most prevalent contaminant class in 72 study areas. Nitrate is most prevalent at high concentrations in 11 study areas, and organic compounds in 4. By the area-metric, 23% of the groundwater used for public supply in CA has high concentrations of one or more contaminants (20,000 of 89,000 km2 assessed). The population-metric, when expressed as a number of people, identifies the potential impact of groundwater contamination. There are 33 CA study areas where the population-metric exceeds 10,000 people (equivalent population multiplied by detection frequency of wells with high concentrations). The population-metric exceeds 50,000 people in 10 study areas. On a statewide basis, the population metric is 2 million people (18% of 11 million equivalent-people). The proposed assessment approach is independent of scale, allows for consistent comparison across regions, and provides a foundation for subsequent economic or health assessments.
Compliance Groundwater Monitoring of Nonpoint Sources - Emerging Approaches
NASA Astrophysics Data System (ADS)
Harter, T.
2008-12-01
Groundwater monitoring networks are typically designed for regulatory compliance of discharges from industrial sites. There, the quality of first encountered (shallow-most) groundwater is of key importance. Network design criteria have been developed for purposes of determining whether an actual or potential, permitted or incidental waste discharge has had or will have a degrading effect on groundwater quality. The fundamental underlying paradigm is that such discharge (if it occurs) will form a distinct contamination plume. Networks that guide (post-contamination) mitigation efforts are designed to capture the shape and dynamics of existing, finite-scale plumes. In general, these networks extend over areas less than one to ten hectare. In recent years, regulatory programs such as the EU Nitrate Directive and the U.S. Clean Water Act have forced regulatory agencies to also control groundwater contamination from non-incidental, recharging, non-point sources, particularly agricultural sources (fertilizer, pesticides, animal waste application, biosolids application). Sources and contamination from these sources can stretch over several tens, hundreds, or even thousands of square kilometers with no distinct plumes. A key question in implementing monitoring programs at the local, regional, and national level is, whether groundwater monitoring can be effectively used as a landowner compliance tool, as is currently done at point-source sites. We compare the efficiency of such traditional site-specific compliance networks in nonpoint source regulation with various designs of regional nonpoint source monitoring networks that could be used for compliance monitoring. We discuss advantages and disadvantages of the site vs. regional monitoring approaches with respect to effectively protecting groundwater resources impacted by nonpoint sources: Site-networks provide a tool to enforce compliance by an individual landowner. But the nonpoint source character of the contamination and its typically large spatial extend requires extensive networks at an individual site to accurately and fairly monitor individual compliance. In contrast, regional networks seemingly fail to hold individual landowners accountable. But regional networks can effectively monitor large-scale impacts and water quality trends; and thus inform regulatory programs that enforce management practices tied to nonpoint source pollution. Regional monitoring networks for compliance purposes can face significant challenges in the implementation due to a regulatory and legal landscape that is exclusively structured to address point sources and individual liability, and due to the non-intensive nature of a regional monitoring program (lack of control of hot spots; lack of accountability of individual landowners).
Wycisk, P; Weiss, H; Kaschl, A; Heidrich, S; Sommerwerk, K
2003-04-11
Large-scale contaminated megasites like Bitterfeld/Wolfen in the eastern part of Germany are characterized by a regional pollution of soil, surface water and groundwater due to the long and varied history of the chemical industry on location. The pollutants in groundwater may spread to uncontaminated areas and endanger receptors like surface water and drinking water wells according to the site-specific hydrologic regime. In addition, the sheer extension of the contamination at megasites as well as the existence of large densely populated areas and land of high-reuse value prevent a simple risk management strategy of use restriction for the whole area. Since a complete clean-up of the groundwater on a megasite is neither economically feasible nor technically possible within a reasonable time-frame, a multi-approach remediation strategy is needed, taking into account the immediate risks for human health, ecosystem and so-called "protectable goods". Moreover, the contaminants at megasites typically represent a dangerous cocktail of multiple harmful substances stemming from a variety of sources, which may interact with each other and complicate the search for an appropriate remediation strategy. At the SAFIRA-project site in Bitterfeld approaches for in situ remediation of multiple contaminants in groundwater are being tested. Alternatives in local implementation strategies as well as consequences of long-term restrictions for megasites like Bitterfeld need an independent evaluation of the situation using a risk-based approach. For this reason, a GIS-based 3D model of the area including geology, contaminants, hydrogeology, land-use and protected areas has been built. The regional groundwater pollution is characterized by contamination profiles of all monitored substances. In the area of investigation, e.g. threefold and fourfold threshold levels of chlorinated methane, ethane and ethene as well as HCH-isomers, mono-, di- and tetrachlorobenzene, DDT-isomers and benzene are frequently detected in groundwater, that means in at least 60% of the wells that were sampled. High median values of more than 10 microg/l were calculated for cis/trans-1,2-dichloroethene, 1,2-dichloroethane, chloroethene and monochlorobenzene. In general, the regional distribution of contaminants reflect the different sources and pathways, and give first results from a regional point of view, depending on a land-use classification of specific areas.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hooten, Gwendolyn; Cato, Rebecca; Looney, Brian
At the US Department of Energy (DOE), Office of Legacy Management, Mound, Ohio, Site, chlorinated organic contaminants (cVOCs) originating from the former solid-waste landfill have impacted groundwater in Operable Unit 1 (OU-1). The baseline groundwater remedy was groundwater pump and treat (P&T). Since the source materials have been removed from the landfill, the Mound core team, which consists of DOE, US Environmental Protection Agency (US EPA), Ohio EPA, and other stakeholders, is assessing the feasibility of switching from the active P&T remedy to a passive attenuation-based remedy. Toward this end, an enhanced attenuation (EA) strategy based on the creation ofmore » structured geochemical zones was developed. This EA strategy addresses the residual areas of elevated cVOCs in soil and groundwater while minimizing the rebound of groundwater concentrations above regulatory targets (e.g., maximum contaminant levels [MCLs]) and avoiding plume expansion while the P&T system is turned off. The EA strategy has improved confidence and reduced risk on the OU-1 groundwater transition path to monitored natural attenuation (MNA). To better evaluate the EA strategy, DOE is conducting a field demonstration to evaluate the use of edible oils to enhance the natural attenuation processes. The field demonstration is designed to determine whether structured geochemical zones can be established that expedite the attenuation of cVOCs in the OU-1 groundwater. The EA approach at OU-1 was designed based on “structured geochemical zones” and relies on groundwater flow through a succession of anaerobic and aerobic zones. The anaerobic zones stimulate relatively rapid degradation of the original solvent source compounds (e.g., cVOCs such as tetrachloroethene [PCE] and trichloroethene [TCE]). The surrounding aerobic areas encourage relatively rapid degradation of daughter products (such as dichloroethene [DCE] and vinyl chloride [VC]) as well as enhanced cometabolism of TCE resulting from the utilization of methane and other reduced hydrocarbons that are formed and released from the anaerobic zones.« less
Superconductive radiofrequency window assembly
Phillips, Harry Lawrence; Elliott, Thomas S.
1998-01-01
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.
Superconductive radiofrequency window assembly
Phillips, H.L.; Elliott, T.S.
1998-05-19
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The SRF window assembly has a superconducting metal-ceramic design. The SRF window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the SRF window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.
Superconducting radiofrequency window assembly
Phillips, Harry L.; Elliott, Thomas S.
1997-01-01
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly (20) has a superconducting metal-ceramic design. The srf window assembly (20) comprises a superconducting frame (30), a ceramic plate (40) having a superconducting metallized area, and a superconducting eyelet (50) for sealing plate (40) into frame (30). The plate (40) is brazed to eyelet (50) which is then electron beam welded to frame (30). A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator.
Superconducting radiofrequency window assembly
Phillips, H.L.; Elliott, T.S.
1997-03-11
The present invention is a superconducting radiofrequency window assembly for use in an electron beam accelerator. The srf window assembly has a superconducting metal-ceramic design. The srf window assembly comprises a superconducting frame, a ceramic plate having a superconducting metallized area, and a superconducting eyelet for sealing plate into frame. The plate is brazed to eyelet which is then electron beam welded to frame. A method for providing a ceramic object mounted in a metal member to withstand cryogenic temperatures is also provided. The method involves a new metallization process for coating a selected area of a ceramic object with a thin film of a superconducting material. Finally, a method for assembling an electron beam accelerator cavity utilizing the srf window assembly is provided. The procedure is carried out within an ultra clean room to minimize exposure to particulates which adversely affect the performance of the cavity within the electron beam accelerator. 11 figs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Isakson, K.; Vessell, A.L.
1994-07-01
Fermilab is presently phasing out all solvents containing Freon-113 (CFC-113) as part of the continuing Waste Minimization Program. These solvents are used primarily in cleaning the flux off of electronic circuit boards after soldering, specifically in bench type work. Title VI of the Clean Air Act mandates a production phase-out for ozone depleting substances, like CFC-113, by the year 2000. Our study addresses this issue by evaluating and choosing alternative non-CFC solvents to replace the CFC-1 13 solvents at Fermilab. Several potential non-CFC cleaning solvents were tested. The evaluation took place in three parts: controlled experimental evaluation, chemical composition evaluation,more » and employee performed evaluation. First, we performed a controlled nine-step procedure with the potential solvents where each was evaluated in categories such as cleaning effectiveness, odor, residue, type of output and drying time. Next, we listed the chemical composition of each solvent. We noted which solvents contained hydrochlorofluorocarbons because they are targeted for phase-out in the future and will be recognized as interim solutions only. Finally, after preliminary testing, five solvents were chosen as the best options. These solvents were sent to be tested by Fermilab employees who use such materials. Their opinions are valuable not only because they are knowledgeable in this field, but also because they will be using the solvents chosen to replace the CFC-113 solvents. The results favored two ``best alternatives``: Safezone Solvent Flux Remover by Miller-Stephenson and E-Series CFC Free Flux-Off 2000 by Chemtech. Another possible solution also pursued is the no-clean solder option. In our study, we were not able to thoroughly investigate the many types of no-clean solders because of time and financial constraints. The testing that was done, however, showed that no-clean solder was a viable alternative in many cases.« less
Quiet Clean Short-haul Experimental Engine (QCSEE) under-the-wing engine simulation report
NASA Technical Reports Server (NTRS)
1977-01-01
Hybrid computer simulations of the under-the-wing engine were constructed to develop the dynamic design of the controls. The engine and control system includes a variable pitch fan and a digital electronic control. Simulation results for throttle bursts from 62 to 100 percent net thrust predict that the engine will accelerate 62 to 95 percent net thrust in one second.
Sinkhole formation and subsidence along the Dead Sea coast, Israel
NASA Astrophysics Data System (ADS)
Yechieli, Yoseph; Abelson, Meir; Baer, Gideon
2016-05-01
More than 4,000 sinkholes have formed since the 1980s within a 60-km-long and 1-km-wide strip along the western coast of the Dead Sea (DS) in Israel. Their formation rate accelerated in recent years to >400 sinkholes per year. They cluster mostly in specific sites up to 1,000 m long and 200 m wide, which align parallel to the general direction of the fault systems associated with the DS Rift. The abrupt appearance of the sinkholes reflects changes to the groundwater regime around the shrinking DS. The eastward retreat of the shoreline and the lake-level drop (1 m/year in recent years) cause an eastward and downward migration of the fresh/saline groundwater interface. Consequently, a subsurface salt layer, which was previously enveloped by saline groundwater, is gradually being invaded and submerged by relatively fresh groundwater, and cavities form due to the rapid dissolution of the salt. Collapse of the overlying sediments into these cavities results in sinkholes at the surface. An association between sinkhole sites and land subsidence is revealed by interferometric synthetic aperture radar (InSAR) measurements. On a broad scale (hundreds of meters), subsidence occurs due to compaction of fine-grained sediments as groundwater levels decline along the retreating DS shoreline. At smaller scales (tens of meters), subsidence appears above subsurface cavities in association with the sinkholes, serving in many cases as sinkhole precursors, a few weeks to more than a year before their actual appearance at the surface. This paper overviews the processes of sinkhole formation and their relation to land subsidence.
Watanabe, Naoko; Bergamaschi, Brian A.; Loftin, Keith A.; Meyer, Michael T.; Harter, Thomas
2010-01-01
Environmental releases of antibiotics from concentrated animal feeding operations (CAFOs) are of increasing regulatory concern. This study investigates the use and occurrence of antibiotics in dairy CAFOs and their potential transport into first-encountered groundwater. On two dairies we conducted four seasonal sampling campaigns, each across 13 animal production and waste management systems and associated environmental pathways: application to animals, excretion to surfaces, manure collection systems, soils, and shallow groundwater. Concentrations of antibiotics were determined using on line solid phase extraction (OLSPE) and liquid chromatography-tandem mass spectrometry (LC/MS/MS) with electrospray ionization (ESI) for water samples, and accelerated solvent extraction (ASE) LC/MS/MS with ESI for solid samples. A variety of antibiotics were applied at both farms leading to antibiotics excretion of several hundred grams per farm per day. Sulfonamides, tetracyclines, and their epimers/isomers, and lincomycin were most frequently detected. Yet, despite decades of use, antibiotic occurrence appeared constrained to within farm boundaries. The most frequent antibiotic detections were associated with lagoons, hospital pens, and calf hutches. When detected below ground, tetracyclines were mainly found in soils, whereas sulfonamides were found in shallow groundwater reflecting key differences in their physicochemical properties. In manure lagoons, 10 compounds were detected including tetracyclines and trimethoprim. Of these 10, sulfadimethoxine, sulfamethazine, and lincomycin were found in shallow groundwater directly downgradient from the lagoons. Antibiotics were sporadically detected in field surface samples on fields with manure applications, but not in underlying sandy soils. Sulfadimethoxine and sulfamethazine were detected in shallow groundwater near field flood irrigation gates, but at highly attenuated levels.
Use and environmental occurrence of antibiotics in freestall dairy farms with manured forage fields.
Watanabe, Naoko; Bergamaschi, Brian A; Loftin, Keith A; Meyer, Michael T; Harter, Thomas
2010-09-01
Environmental releases of antibiotics from concentrated animal feeding operations (CAFOs) are of increasing regulatory concern. This study investigates the use and occurrence of antibiotics in dairy CAFOs and their potential transport into first-encountered groundwater. On two dairies we conducted four seasonal sampling campaigns, each across 13 animal production and waste management systems and associated environmental pathways: application to animals, excretion to surfaces, manure collection systems, soils, and shallow groundwater. Concentrations of antibiotics were determined using on line solid phase extraction (OLSPE) and liquid chromatography-tandem mass spectrometry (LC/MS/MS) with electrospray ionization (ESI) for water samples, and accelerated solvent extraction (ASE) LC/MS/MS with ESI for solid samples. A variety of antibiotics were applied at both farms leading to antibiotics excretion of several hundred grams per farm per day. Sulfonamides, tetracyclines, and their epimers/isomers, and lincomycin were most frequently detected. Yet, despite decades of use, antibiotic occurrence appeared constrained to within farm boundaries. The most frequent antibiotic detections were associated with lagoons, hospital pens, and calf hutches. When detected below ground, tetracyclines were mainly found in soils, whereas sulfonamides were found in shallow groundwater reflecting key differences in their physicochemical properties. In manure lagoons, 10 compounds were detected including tetracyclines and trimethoprim. Of these 10, sulfadimethoxine, sulfamethazine, and lincomycin were found in shallow groundwater directly downgradient from the lagoons. Antibiotics were sporadically detected in field surface samples on fields with manure applications, but not in underlying sandy soils. Sulfadimethoxine and sulfamethazine were detected in shallow groundwater near field flood irrigation gates, but at highly attenuated levels.
Use and Environmental Occurrence of Antibiotics in Freestall Dairy Farms with Manured Forage Fields
2010-01-01
Environmental releases of antibiotics from concentrated animal feeding operations (CAFOs) are of increasing regulatory concern. This study investigates the use and occurrence of antibiotics in dairy CAFOs and their potential transport into first-encountered groundwater. On two dairies we conducted four seasonal sampling campaigns, each across 13 animal production and waste management systems and associated environmental pathways: application to animals, excretion to surfaces, manure collection systems, soils, and shallow groundwater. Concentrations of antibiotics were determined using on line solid phase extraction (OLSPE) and liquid chromatography-tandem mass spectrometry (LC/MS/MS) with electrospray ionization (ESI) for water samples, and accelerated solvent extraction (ASE) LC/MS/MS with ESI for solid samples. A variety of antibiotics were applied at both farms leading to antibiotics excretion of several hundred grams per farm per day. Sulfonamides, tetracyclines, and their epimers/isomers, and lincomycin were most frequently detected. Yet, despite decades of use, antibiotic occurrence appeared constrained to within farm boundaries. The most frequent antibiotic detections were associated with lagoons, hospital pens, and calf hutches. When detected below ground, tetracyclines were mainly found in soils, whereas sulfonamides were found in shallow groundwater reflecting key differences in their physicochemical properties. In manure lagoons, 10 compounds were detected including tetracyclines and trimethoprim. Of these 10, sulfadimethoxine, sulfamethazine, and lincomycin were found in shallow groundwater directly downgradient from the lagoons. Antibiotics were sporadically detected in field surface samples on fields with manure applications, but not in underlying sandy soils. Sulfadimethoxine and sulfamethazine were detected in shallow groundwater near field flood irrigation gates, but at highly attenuated levels. PMID:20698525
NASA Astrophysics Data System (ADS)
Atlabachew, Abunu; Shu, Longcang; Wu, Peipeng; Zhang, Yongjie; Xu, Yang
2018-03-01
This laboratory study improves the understanding of the impacts of horizontal hydraulic gradient, artificial recharge, and groundwater pumping on solute transport through aquifers. Nine experiments and numerical simulations were carried out using a sand tank. The variable-density groundwater flow and sodium chloride transport were simulated using the three-dimensional numerical model SEAWAT. Numerical modelling results successfully reproduced heads and concentrations observed in the sand tank. A higher horizontal hydraulic gradient enhanced the migration of sodium chloride, particularly in the groundwater flow direction. The application of constant artificial recharge increased the spread of the sodium chloride plume in both the longitudinal and lateral directions. In addition, groundwater pumping accelerated spreading of the sodium chloride plume towards the pumping well. Both higher hydraulic gradient and pumping rate generated oval-shaped plumes in the horizontal plane. However, the artificial recharge process produced stretched plumes. These effects of artificial recharge and groundwater pumping were greater under higher hydraulic gradient. The concentration breakthrough curves indicated that emerging solutions never attained the concentration of the originally injected solution. This is probably because of sorption of sodium chloride onto the silica sand and/or the exchange of sodium chloride between the mobile and immobile liquid domains. The fingering and protruding plume shapes in the numerical models constitute instability zones produced by buoyancy-driven flow. Overall, the results have substantiated the influences of hydraulic gradient, boundary condition, artificial recharge, pumping rate and density differences on solute transport through a homogeneous unconfined aquifer. The implications of these findings are important for managing liquid wastes.
NASA Astrophysics Data System (ADS)
Kennedy, C. D.; Gall, H.; Jafvert, C. T.; Bowen, G. J.
2010-12-01
Subsurface (‘tile’) drainage, consisting of buried grids of perforated pipe, has provided a means of converting millions of acres of poorly drained soils in the Midwestern U.S. into fertile cropland. However, by altering pathways and rates of soil water and groundwater movement through agricultural lands, this practice may accelerate the loss of nitrate and other agrochemicals. To better understand the hydrological controls on nitrogen dynamics in artificially drained agricultural watersheds, a field sampling program has been established at the Animal Science Research and Education Center (ASREC) at Purdue University (West Lafayette, Indiana) to (1) measure precipitation amount, tile flow, and water-table elevation, and (2) collect water samples for analysis of nitrate, major ions, and oxygen isotope ratios in precipitation, tile drainage, shallow (1 m) and deep (3 m) groundwater, and soil water during storm events. Preliminary physical, chemical, and isotopic data collected at the ASREC show a coincident timing of peak storm ‘event water’ and peak nitrate flux in tile drainage, suggesting significant routing of infiltrating event water. In this work, we aim to refine our understanding of tile drainage at the ASREC by developing a mixing model for partitioning contributions of soil water and groundwater in tile drainage during several storm runoff events ranging in precipitation intensity and coinciding with varying antecedent soil moisture conditions. The results of our model will describe tile drainage in terms of its hydrological components, soil water and groundwater, which in turn will provide a means of incorporating the effects of tile drainage in surface/subsurface hydrological transport models.
Rise and Fall of one of World's largest deltas; the Mekong delta in Vietnam
NASA Astrophysics Data System (ADS)
Minderhoud, P. S. J.; Eslami Arab, S.; Pham, H. V.; Erkens, G.; van der Vegt, M.; Oude Essink, G.; Stouthamer, E.; Hoekstra, P.
2017-12-01
The Mekong delta is the third's largest delta in the world. It is home to almost 20 million people and an important region for the food security in South East Asia. As most deltas, the Mekong delta is the dynamic result of a balance of sediment supply, sea level rise and subsidence, hosting a system of fresh and salt water dynamics. Ongoing urbanization, industrialization and intensification of agricultural practices in the delta, during the past decades, resulted in growing domestic, agricultural and industrial demands, and have led to a dramatic increase of fresh water use. Since the year 2000, the amount of fresh groundwater extracted from the subsurface increased by 500%. This accelerated delta subsidence as the groundwater system compacts, with current sinking rates exceeding global sea level rise up to an order of magnitude. These high sinking rates have greatly altered the sediment budget of the delta and, with over 50% of the Mekong delta surface elevated less than 1 meter above sea level, greatly increase vulnerability to flooding and storm surges and ultimately, permanent inundation. Furthermore, as the increasingly larger extractions rapidly reduce the fresh groundwater reserves, groundwater salinization subsequently increases. On top of that, dry season low-flows by the Mekong river cause record salt water intrusion in the delta's estuarine system, creating major problems for rice irrigation. We present the work of three years research by the Dutch-Vietnamese `Rise and Fall' project on land subsidence and salinization in both groundwater and surface water in the Vietnamese Mekong delta.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ferris, F. Grant; Fujita, Yoshiko; Smith, Robert W.
2004-06-15
Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) weapons complex. In situ containment and stabilization of these contaminants in vadose zones or groundwater is a cost-effective treatment strategy. Our facilitated approach relies upon the hydrolysis of introduced urea to cause the acceleration of calcium carbonate precipitation (and trace metal coprecipitation) by increasing groundwater pH and alkalinity (Fujita et al., 2000; Warren et al., 2001). Subsurface urea hydrolysis is catalyzed by the urease enzyme, which may be either introduced with the urea or produced in situ by ubiquitous subsurface ureamore » hydrolyzing microorganisms. Because the precipitation processes are irreversible and many western aquifers are saturated with respect to calcite, the co-precipitated metals and radionuclides will be effectively removed from groundwater. The rate at which trace metals are incorporated into calcite is a function of calcite precipitation kinetics, adsorption interactions between the calcite surface and the trace metal in solution (Zachara et al., 1991), solid solution properties of the trace metal in calcite (Tesoriero and Pankow, 1996), and also the surfaces upon which the calcite is precipitating. A fundamental understanding of the coupling of calcite precipitation and trace metal partitioning, and how this occurs in aquifers and vadose environments is lacking. This report summarizes work undertaken during the second year of this project.« less
NASA Astrophysics Data System (ADS)
Penny, G.; Srinivasan, V.; Thompson, S. E.
2017-12-01
Rapid acceleration of human-water interactions have been identified in many regions of the world, often resulting in reduced water security. In the Arkavathy watershed adjacent to Bangalore, India, environmental and human systems have collectively experienced major transformations since the initiation of sustainable agriculture near the beginning of the Holocene. We reconstruct a narrative history of water security in the Arkavathy, focusing on quantitative metrics of productivity, equity, and resilience. Over this time period, the system can be separated into multiple distinct eras characterized by the dominant practices of agriculture and water management, including the unmanaged (natural) plant ecology of the region, followed by subsistence farming, tank irrigation, construction of large reservoirs, groundwater depletion, and decentralized adaptation. Each of these eras was initiated by a combination of external drivers (e.g., climate, technology) and internal drivers (e.g., demand for food and water). The last fifty years have been characterized by rapid increase in productivity largely sustained by expansion of groundwater irrigation and increasing demand from the rapidly urbanizing Bangalore. Equity initially increased with the introduction of groundwater irrigation and the increased access to irrigation supply. As the water table declined and groundwater irrigation became less affordable, resilience of the system decreased and was followed by a decrease in equity and productivity, with wealthier farmers reaping the benefits and poorer farmers unable to afford access to groundwater. Absent meaningful changes to water rights policy, the system appears to be trending towards a new, undesirable equilibrium characterized by high inequality, moderate productivity (concentrated among the wealthiest farmers), and low resilience.
García-Gil, Alejandro; Gasco-Cavero, Samanta; Garrido, Eduardo; Mejías, Miguel; Epting, Jannis; Navarro-Elipe, Mercedes; Alejandre, Carmen; Sevilla-Alcaine, Elena
2018-08-15
The implications of intensive use of shallow geothermal energy resources in shallow urban aquifers are still not known for waterborne pathogens relevant to human health. Firstly, we hypothesized that waterborne enteric pathogens would be relatively increased in heated groundwater plumes. To prove this, microbiological sampling of 31 piezometers covering the domain of an urban groundwater body affected by microbiological contamination and energetically exploited by 70 groundwater heat pump systems was performed. Mean differences of pathogenic bacteria contents between impacted and non-impacted monitoring points were assessed with a two-tailed independent Student's t-test or Mann-Whitney U and correlation coefficients were also calculated. Surprisingly, the results obtained revealed a significant and generalized decrease in waterborne pathogen contents in thermally impacted piezometers compared to that of non-impacted piezometers. This decrease is hypothesized to be caused by a heat shock to bacteria within the heat exchangers. The statistically significant negative correlations obtained between waterborne pathogen counts and temperature could be explained by the spatial distribution of the bacteria, finding that bacteria start to recover with increasing distance from the injection point. Also, different behavior groups fitting exponential regression models were found for the bacteria species studied, justified by the different presence and influence of several aquifer parameters and major, minor and trace elements studied, as well as the coexistence with other bacteria species. The results obtained from this work reinforce the concept of shallow geothermal resources as a clean energy source, as they could also provide the basis to control the pathogenic bacteria contents in groundwater bodies. Copyright © 2018 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dorr, Kent A.; Freeman-Pollard, Jhivaun R.; Ostrom, Michael J.
CH2M Hill Plateau Remediation Company (CHPRC) designed, constructed, commissioned, and began operation of the largest groundwater pump and treatment facility in the U.S. Department of Energy's (DOE) nationwide complex. This one-of-a-kind groundwater pump and treatment facility, located at the Hanford Nuclear Reservation Site (Hanford Site) in Washington State, was built to an accelerated schedule with American Recovery and Reinvestment Act (ARRA) funds. There were many contractual, technical, configuration management, quality, safety, and Leadership in Energy and Environmental Design (LEED) challenges associated with the design, procurement, construction, and commissioning of this $95 million, 52,000 ft groundwater pump and treatment facility tomore » meet DOE's mission objective of treating contaminated groundwater at the Hanford Site with a new facility by June 28, 2012. The project team's successful integration of the project's core values and green energy technology throughout design, procurement, construction, and start-up of this complex, first-of-its-kind Bio Process facility resulted in successful achievement of DOE's mission objective, as well as attainment of LEED GOLD certification (Figure 1), which makes this Bio Process facility the first non-administrative building in the DOE Office of Environmental Management complex to earn such an award. (authors)« less
Yuan, Songhu; Liao, Peng; Alshawabkeh, Akram N.
2014-01-01
Activated persulfate oxidation is an effective in situ chemical oxidation process for groundwater remediation. However, reactivity of persulfate is difficult to manipulate or control in the subsurface causing activation before reaching the contaminated zone and leading to a loss of chemicals. Furthermore, mobilization of heavy metals by the process is a potential risk. An effective approach using iron electrodes is thus developed to manipulate the reactivity of persulfate in situ for trichloroethylene (TCE) degradation in groundwater, and to limit heavy metals mobilization. TCE degradation is quantitatively accelerated or inhibited by adjusting the current applied to the iron electrode, following k1 = 0.00053•Iv + 0.059 (−122 A/m3 ≤ Iv ≤ 244 A/m3) where k1 and Iv are the pseudo first-order rate constant (min−1) and volume normalized current (A/m3), respectively. Persulfate is mainly decomposed by Fe2+ produced from the electrochemical and chemical corrosion of iron followed by the regeneration via Fe3+ reduction on the cathode. SO4•− and •OH co-contribute to TCE degradation, but •OH contribution is more significant. Groundwater pH and oxidation-reduction potential can be restored to natural levels by the continuation of electrolysis after the disappearance of contaminants and persulfate, thus decreasing adverse impacts such as the mobility of heavy metals in the subsurface. PMID:24328192
HANFORD SITE RIVER CORRIDOR CLEANUP
DOE Office of Scientific and Technical Information (OSTI.GOV)
BAZZELL, K.D.
2006-02-01
In 2005, the US Department of Energy (DOE) launched the third generation of closure contracts, including the River Corridor Closure (RCC) Contract at Hanford. Over the past decade, significant progress has been made on cleaning up the river shore that bordes Hanford. However, the most important cleanup challenges lie ahead. In March 2005, DOE awarded the Hanford River Corridor Closure Contract to Washington Closure Hanford (WCH), a limited liability company owned by Washington Group International, Bechtel National and CH2M HILL. It is a single-purpose company whose goal is to safely and efficiently accelerate cleanup in the 544 km{sup 2} Hanfordmore » river corridor and reduce or eliminate future obligations to DOE for maintaining long-term stewardship over the site. The RCC Contract is a cost-plus-incentive-fee closure contract, which incentivizes the contractor to reduce cost and accelerate the schedule. At $1.9 billion and seven years, WCH has accelerated cleaning up Hanford's river corridor significantly compared to the $3.2 billion and 10 years originally estimated by the US Army Corps of Engineers. Predictable funding is one of the key features of the new contract, with funding set by contract at $183 million in fiscal year (FY) 2006 and peaking at $387 million in FY2012. Another feature of the contract allows for Washington Closure to perform up to 40% of the value of the contract and subcontract the balance. One of the major challenges in the next few years will be to identify and qualify sufficient subcontractors to meet the goal.« less
NASA Astrophysics Data System (ADS)
Zhang, M.; Yoshikawa, M.; Takeuchi, M.; Komai, T.
2011-12-01
Chlorinated ethenes, like perchloroethene (PCE) and trichloroethene (TCE), have been widely used by many industries, especially in developed countries like Japan. Because of their wide applications, lack of proper regulation, poor handing, storage and disposal practices in the past, chlorinated ethenes have become a type of the most prevalent contaminants for soils and groundwater pollution. For the sake of their degradability, bioremediation has been considered as a potentially cost-effective and environmentally friendly approach for cleanup of chlorinated ethenes in situ. In this presentation, we briefly overview the status of soil and groundwater pollution, the recent amendment of the Soil Contamination Countermeasures Act in Japan, comparison between the bioremediation and other techniques like pump and treat, and the mechanisms of reductive dechlorination, direct oxidation and co-metabolism of chlorinated ethenes. We then introduce and discuss some recent challenges and advancements in in-situ bioremediation including technologies for accelerating bio-degradation of chlorinated ethenes, technologies for assessing diffusive properties of dissolved hydrogen in hydraulically-tight soil samples, and combination of bioremediation with other techniques like electro-kinetic approach. Limiting factors that may cause incomplete remediation and/or ineffectiveness of bioremediation are examined from biochemical, geochemical and hydro-geological aspects. This study reconfirmed and illustrated that: 1) The key factor for an effective bioremediation is how to disperse a proper accelerating agent throughout the polluted strata, 2) The effective diffusion coefficient of dissolved hydrogen in geologic media is relatively big and is almost independent on their permeability, and 3) To effectively design and perform an accelerated bioremediation, a combination of natural migration with pressurized injection and/or other approaches, like electro-migration, for stimulating mass transport could be necessary depending on the hydraulic properties, like porosity and permeability of a stratum.
In Situ Oxalic Acid Injection to Accelerate Arsenic Remediation at a Superfund Site in New Jersey
Wovkulich, Karen; Stute, Martin; Mailloux, Brian J.; Keimowitz, Alison R.; Ross, James; Bostick, Benjamin; Sun, Jing; Chillrud, Steven N.
2015-01-01
Arsenic is a prevalent contaminant at a large number of US Superfund sites; establishing techniques that accelerate As remediation could benefit many sites. Hundreds of tons of As were released into the environment by the Vineland Chemical Co. in southern New Jersey during its manufacturing lifetime (1949–1994), resulting in extensive contamination of surface and subsurface soils and sediments, groundwater, and the downstream watershed. Despite substantial intervention at this Superfund site, sufficient aquifer cleanup could require many decades if based on traditional pump and treat technologies only. Laboratory column experiments have suggested that oxalic acid addition to contaminated aquifer solids could promote significant As release from the solid phase. To evaluate the potential of chemical additions to increase As release in situ and boost treatment efficiency, a forced gradient pilot scale study was conducted on the Vineland site. During spring/summer 2009, oxalic acid and bromide tracer were injected into a small portion (~50 m2) of the site for 3 months. Groundwater samples indicate that introduction of oxalic acid led to increased As release. Between 2.9 and 3.6 kg of As were removed from the sampled wells as a result of the oxalic acid treatment during the 3-month injection. A comparison of As concentrations on sediment cores collected before and after treatment and analyzed using X-ray fluorescence spectroscopy suggested reduction in As concentrations of ~36% (median difference) to 48% (mean difference). While further study is necessary, the addition of oxalic acid shows potential for accelerating treatment of a highly contaminated site and decreasing the As remediation time-scale. PMID:25598701
Tenbus, F.J.; Fleck, W.B.
1996-01-01
Ground water in the east-central part of Graces Quarters, a former open-air chemical-agent test facility at Aberdeen Proving Ground, Maryland, is contaminated with chlorinated volatile organic compounds. The U.S. Geological Survey's finite- difference model was used to help understand ground-water flow and simulate the effects of alternative remedial actions to clean up the ground water. Scenarios to simulate unstressed conditions and three extraction well con- figurations were used to compare alternative remedial actions on the contaminant plume. The scenarios indicate that contaminants could migrate from their present location to wetland areas within 10 years under unstressed conditions. Pumping 7 gal/min (gallons per minute) from one well upgradient of the plume will not result in containment or removal of the highest contaminant concentrations. Pumping 7 gal/min from three wells along the central axis of the plume should result in containment and removal of dissolved contami- nants, as should pumping 7 gal/min from three wells at the leading edge of the plume while injecting 7 gal/min back into an upgradient well.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1990-09-28
The Garden State Cleaners Company is a dry cleaning establishment located in Buena Borough, New Jersey. Contaminated wastewater from on-site operations was routinely discharged to on-site soils. Analytical data has described significant soil and ground-water contamination from tetrachloroethylene (PCE) and other volatile organic compounds. Ground-water contamination downgradient (to the south) of the site has required the recommended closing of private wells and the installation of a municipal water supply system. An Administrative Order and Notice of Civil Administrative Penalty Assessment (AO and PSO) were issued to Garden State Cleaners in December 1985, requiring GSC to perform a full RI/FS. Municipalmore » water supplies have been made available to affected residens, but utilization is elective. The site was included on the NPL list in March 1989 and is currently ranked 105 of 108 sites in New Jersey. ATSDR and NJDOH consider the Garden State Cleaners site to be of public health concern. The site is being considered for follow-up health study or evaluation.« less
1999-04-06
On the site of Launch Complex 34, key participants sign a Memorandum of Agreement, formalizing cooperative efforts of NASA, the U.S. Air Force, and federal agencies in ground-water cleanup initiatives. Seated from left to right are Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; Roy Bridges Jr., director of John F. Kennedy Space Center; Walter Kovalick Jr., Ph.D., director, Technology Innovation Office, U.S. Environmental Protection Agency. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The Tyler Refrigeration Pit site from 1952 until 1969 was used to dispose of metal cleaning solvents and paint room wastes. On-site contamination consists of toluene (25 ppm), 1,1-dichloroethane (10 ppm), and 1,1,1-trichloroethane (15 ppm) in soil. Off-site contamination consists of trichloroethylene (70 ppb) in groundwater. The presence of trichloroethylene in the public water supply, exceeding the Safe Drinking Water Act's Maximum Contaminant Level of 5 ppb, is considered to be a public health threat. From the information available, ATSDR cannot comment on the public health implications of the Tyler Refrigeration Pit.
Xie, X S; Qi, C; Du, X Y; Shi, W W; Zhang, M
2016-02-20
To investigate the features of hand-transmitted vibration of common vibration tools in the workplace for automobile casting and assembly. From September to October, 2014, measurement and spectral analysis were performed for 16 typical hand tools(including percussion drill, pneumatic wrench, grinding machine, internal grinder, and arc welding machine) in 6 workplaces for automobile casting and assembly according to ISO 5349-1-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-part 1: General requirements and ISO 5349-2-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 2: Practical guidance for measurement in the workplace. The vibration acceleration waveforms of shearing machine, arc welding machine, and pneumatic wrench were mainly impact wave and random wave, while those of internal grinder, angle grinder, percussion drill, and grinding machine were mainly long-and short-period waves. The daily exposure duration to vibration of electric wrench, pneumatic wrench, shearing machine, percussion drill, and internal grinder was about 150 minutes, while that of plasma cutting machine, angle grinder, grinding machine, bench grinder, and arc welding machine was about 400 minutes. The range of vibration total value(ahv) was as follows: pneumatic wrench 0.30~11.04 m/s(2), grinding wheel 1.61~8.97 m/s(2), internal grinder 1.46~8.70 m/s(2), percussion drill 11.10~14.50 m/s(2), and arc welding machine 0.21~2.18 m/s(2). The workers engaged in cleaning had the longest daily exposure duration to vibration, and the effective value of 8-hour energy-equivalent frequency-weighted acceleration for them[A(8)] was 8.03 m/s(2), while this value for workers engaged in assembly was 4.78 m/s(2). The frequency spectrogram with an 1/3-time frequency interval showed that grinding machine, angle grinder, and percussion drill had a high vibration acceleration, and the vibration limit curve was recommended for those with a frequency higher than 400 min/d. The workers who are engaged in cleaning, grinding, and a few positions of assembly and use grinding machine, angle grinder, internal grinder, and percussion drill are exposed to vibrations with a high vibration acceleration and at a high position of the frequency spectrum. The hand-transmitted vibration in the positions of cutting, polishing, and cleaning in automobile casting has great harm, and the harm caused by pneumatic wrench in automobile assembly should be taken seriously.
Aoki, Jun-ya; Hatsuyama, Ayaka; Hiramatsu, Naoshi; Soyano, Kiyoshi
2011-11-01
We investigated the continuing effects of exposure to ethynylestradiol (EE(2)) in juvenile grey mullet after transfer to a clean environment. Eleven-month-old juvenile fish containing immature phenotype gonad were fed dry diets; the low and high EE(2)-treated groups were fed diets with 0.04 and 4 μg EE(2)/g body weight for 4 weeks, respectively. After treatment, they were transferred to clean seawater, and reared with an EE(2) free diet for 350 days. Vitellogenin (VTG) was not detected in the serum of the control group throughout the experimental period. However, in both treatment groups, abnormal values of serum VTG were detected until approximately 100 days after transfer to a clean environment. In the control group, sex differentiation was not confirmed until 206 days after transfer to a clean environment. However, some of the fish in the 0.04 μg EE(2)-treated group had ovarian cavity and oocytes at 26 days. In most of the fish in the 4 μg EE(2)-treated group, the ovarian cavity had already appeared at the end of EE(2) treatment (0 day), and oocytes were observed at 26 days, suggesting that EE(2) accelerates ovarian differentiation. These results suggest that previous exposure to EE(2) has long-term effects on VTG synthesis and gonadal development. Copyright © 2011 Elsevier Inc. All rights reserved.
Apparatus and method for in-situ cleaning of resist outgassing windows
Klebanoff, Leonard E.; Haney, Steven J.
2001-01-01
An apparatus and method for in-situ cleaning of resist outgassing windows. The apparatus includes a chamber located in a structure, with the chamber having an outgassing window to be cleaned positioned in alignment with a slot in the chamber, whereby radiation energy passes through the window, the chamber, and the slot onto a resist-coated wafer mounted in the structure. The chamber is connected to a gas supply and the structure is connected to a vacuum pump. Within the chamber are two cylindrical sector electrodes and a filament is electrically connected to one sector electrode and a power supply. In a first cleaning method the sector electrodes are maintained at the same voltage, the filament is unheated, the chamber is filled with argon (Ar) gas under pressure, and the window is maintained at a zero voltage, whereby Ar ions are accelerated onto the window surface, sputtering away carbon deposits that build up as a result of resist outgassing. A second cleaning method is similar except oxygen gas (O.sub.2) is admitted to the chamber instead of Ar. These two methods can be carried out during lithographic operation. A third method, carried out during a maintenance period, involves admitting CO.sub.2 into the chamber, heating the filament to a point of thermionic emission, the sector electrodes are at different voltages, excited CO.sub.2 gas molecules are created which impact the carbon contamination on the window, and gasify it, producing CO gaseous products that are pumped away.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-09-28
The 200-acre Kin-Buc Landfill consists of several inactive disposal areas and is located in Edison Township, Middlesex County, New Jersey. Land use in the area is predominantly industrial and commercial, with some residences within 2 miles north of the site. No drinking water supply wells are located within a 2-mile radius of the site. As a result of an oil spill in 1976, EPA conducted an investigation of the property. In 1980, clean-up activities were initiated under the Clean Water Act and included removal, treatment, and disposal of leachate and drummed waste. The ROD addresses a final remedy for OU2more » consisting of the sediment and groundwater in the Edmonds Creek wetlands area, Mill Brook/Martins Creek, Mound B, and the low-lying area. The primary contaminants of concern affecting the sediment and ground water are VOCs, including benzene and xylenes; other organics, including PAHs, PCBs, and pesticides; and metals, including arsenic and lead. The selected remedy for the site are included.« less
Tang, Li; Iddya, Arpita; Zhu, Xiaobo; Dudchenko, Alexander V; Duan, Wenyan; Turchi, Craig; Vanneste, Johann; Cath, Tzahi Y; Jassby, David
2017-11-08
The desalination of inland brackish groundwater offers the opportunity to provide potable drinking water to residents and industrial cooling water to industries located in arid regions. Geothermal brines are used to generate electricity, but often contain high concentrations of dissolved salt. Here, we demonstrate how the residual heat left in spent geothermal brines can be used to drive a membrane distillation (MD) process and recover desalinated water. Porous polypropylene membranes were coated with a carbon nanotube (CNT)/poly(vinyl alcohol) layer, resulting in composite membranes having a binary structure that combines the hydrophobic properties critical for MD with the hydrophilic and conductive properties of the CNTs. We demonstrate that the addition of the CNT layer increases membrane flux due to enhanced heat transport from the bulk feed to the membrane surface, a result of CNT's high thermal transport properties. Furthermore, we show how hydroxide ion generation, driven by water electrolysis on the electrically conducting membrane surface, can be used to efficiently dissolve silicate scaling that developed during the process of desalinating the geothermal brine, negating the need for chemical cleaning.
Advanced Photon Source accelerator ultrahigh vacuum guide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, C.; Noonan, J.
1994-03-01
In this document the authors summarize the following: (1) an overview of basic concepts of ultrahigh vacuum needed for the APS project, (2) a description of vacuum design and calculations for major parts of APS, including linac, linac waveguide, low energy undulator test line, positron accumulator ring (PAR), booster synchrotron ring, storage ring, and insertion devices, and (3) cleaning procedures of ultrahigh vacuum (UHV) components presently used at APS.
NASA Helps Build Colorado Economy
2010-12-13
NASA Deputy Administrator Lori Garver delivers remarks at the Colorado State Capitol in Denver on Monday, Dec. 13, 2010, prior to signing an agreement that creates a Technology Acceleration Program and Regional Innovation Cluster for Aerospace and Clean Energy. A manufacturing park focused on rapid new product development and production will be developed to assist growing Colorado businesses while promoting the commercialization of technology developed for the space program. Photo Credit: (NASA/Bill Ingalls)
Proceeding of the 1999 Particle Accelerator Conference. Volume 2
1999-04-02
anill repron the enorag cat manufacturing costs for such devices are significant and a pefnces acd after vari ouroeing steps drastic reduction in...cleanroom contractors, to find one that could meet our needs. Clean Air Technology 4 THEORY OF OPERATION ( CAT ) was able to provide a modular cleanroom...that would accommodate our unusual building geometry. CAT The facility improvements were designed to be used in provided the cleanroom, a local
NASA Astrophysics Data System (ADS)
Tyagi, P. V.; Moss, Andrew; Goudket, Philippe; Pattalwar, Shrikant; Herbert, Joe; Valizadeh, Reza; McIntosh, Peter
2018-06-01
Field emission is one of the critical issues in the superconducting radio frequency (SRF) cavities and can degrade their accelerating gradient during operation. The contamination present at top surface of the SRF cavity is one of the foremost reasons for field emission. Plasma based surface processing can be a viable option to eliminate such surface contaminants and enhance performance of the SRF cavity especially for in-situ applications. These days, 1.3 GHz nine-cell SRF cavity has become baseline standard for many particle accelerators, it is of interest to develop plasma cleaning technique for such SRF cavities. In the development of the plasma processing technique for SRF cavities, the most challenging task is to ignite and tune the plasma in different cells of the SRF cavity. At Daresbury laboratory, UK, we have successfully achieved plasma ignition in different cells of a 1.3 GHz nine-cell SRF cavity. The plasma ignition in different cells of the cavity was accomplished at room temperature towards room temperature plasma cleaning of the SRF cavity surface. Here, we report the successful demonstration of the plasma ignition in different cells of a 1.3 GHz nine-cell SRF cavity.
Yucca Mountain Area Saturated Zone Dissolved Organic Carbon Isotopic Data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomas, James; Decker, David; Patterson, Gary
2007-06-25
Groundwater samples in the Yucca Mountain area were collected for chemical and isotopic analyses and measurements of water temperature, pH, specific conductivity, and alkalinity were obtained at the well or spring at the time of sampling. For this project, groundwater samples were analyzed for major-ion chemistry, deuterium, oxygen-18, and carbon isotopes of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC). The U.S. Geological Survey (USGS) performed all the fieldwork on this project including measurement of water chemistry field parameters and sample collection. The major ions dissolved in the groundwater, deuterium, oxygen-18, and carbon isotopes of dissolved inorganic carbon (DIC)more » were analyzed by the USGS. All preparation and processing of samples for DOC carbon isotopic analyses and geochemical modeling were performed by the Desert Research Institute (DRI). Analysis of the DOC carbon dioxide gas produced at DRI to obtain carbon-13 and carbon-14 values was conducted at the University of Arizona Accelerator Facility (a NSHE Yucca Mountain project QA qualified contract facility). The major-ion chemistry, deuterium, oxygen-18, and carbon isotopes of DIC were used in geochemical modeling (NETPATH) to determine groundwater sources, flow paths, mixing, and ages. The carbon isotopes of DOC were used to calculate groundwater ages that are independent of DIC model corrected carbon-14 ages. The DIC model corrected carbon-14 calculated ages were used to evaluate groundwater travel times for mixtures of water including water beneath Yucca Mountain. When possible, groundwater travel times were calculated for groundwater flow from beneath Yucca Mountain to down gradient sample sites. DOC carbon-14 groundwater ages were also calculated for groundwaters in the Yucca Mountain area. When possible, groundwater travel times were estimated for groundwater flow from beneath Yucca Mountain to down gradient groundwater sample sites using the DOC calculated groundwater ages. The DIC calculated groundwater ages were compared with DOC calculated groundwater ages and both of these ages were compared to travel times developed in ground-water flow and transport models. If nuclear waste is stored in Yucca Mountain, the saturated zone is the final barrier against the release of radionuclides to the environment. The most recent rendition of the TSPA takes little credit for the presence of the saturated zone and is a testament to the inadequate understanding of this important barrier. If radionuclides reach the saturated zone beneath Yucca Mountain, then there is a travel time before they would leave the Yucca Mountain area and flow down gradient to the Amargosa Valley area. Knowing how long it takes groundwater in the saturated zone to flow from beneath Yucca Mountain to down gradient areas is critical information for potential radionuclide transport. Radionuclide transport in groundwater may be the quickest pathway for radionuclides in the proposed Yucca Mountain repository to reach land surface by way of groundwater pumped in Amargosa Valley. An alternative approach to ground-water flow and transport models to determine the travel time of radionuclides from beneath Yucca Mountain to down gradient areas in the saturated zone is by carbon-14 dating of both inorganic and organic carbon dissolved in the groundwater. A standard method of determining ground-water ages is to measure the carbon-13 and carbon-14 of DIC in the groundwater and then correct the measured carbon-14 along a flow path for geochemical reactions that involve carbon containing phases. These geochemical reactions are constrained by carbon-13 and isotopic fractionations. Without correcting for geochemical reactions, the ground-water ages calculated from only the differences in carbon-14 measured along a flow path (assuming the decrease in carbon-14 is due strictly to radioactive decay) could be tens of thousands of years too old. The computer program NETPATH, developed by the USGS, is the best geochemical program for correcting carbon-14 activities for geochemical reactions. The DIC carbon-14 corrected ages can be further constrained by measuring the carbon isotopes of DOC. Because the only source of organic carbon in aquifers is almost always greater than 40,000 years old, any organic carbon that may be added to the groundwater would contain no carbon-14. Thus, ground-water ages determined by carbon isotopes of DOC should be maximum ages that can be used to constrain DIC corrected ages.« less
Alloy Corrosion Considerations in Low-Cost, Clean Biomass Cookstoves for the Developing World
Brady, Michael P.; Banta, Kelly; Mizia, John; ...
2017-04-01
In nearly 40% of the world cooks on open fires or inefficient biomass-fueled cookstoves. The resulting smoke is a health hazard, contributing to an estimated 4 million premature deaths per year, as well as a major source of black carbon emissions. One solution is the introduction of improved, clean-burning biomass cookstoves. One of the most challenging components is the combustor, which must operate at high temperatures (often ≥ 600 °C) in the presence of highly corrosive species released from biomass fuel combustion, yet be sufficiently low cost to permit widespread adoption. In our present work we report the development ofmore » accelerated corrosion test screening protocols employing highly corrosive salt and water vapor species, specifically designed to evaluate alloys for clean biomass cookstove combustors, and corrosion findings for a range of commercial and developmental alloys. Lastly, a new Fe-Cr-Si base alloy that offers promise for improved corrosion resistance at lower cost than state-of the art FeCrAl and stainless steel alloys is also reported.« less
Corrosion Behavior of Cu40Zn in Sulfide-Polluted 3.5% NaCl Solution
NASA Astrophysics Data System (ADS)
Song, Q. N.; Xu, N.; Bao, Y. F.; Jiang, Y. F.; Gu, W.; Yang, Z.; Zheng, Y. G.; Qiao, Y. X.
2017-10-01
The corrosion behavior of a duplex-phase brass Cu40Zn in clean and sulfide-polluted 3.5% NaCl solutions was investigated by conducting electrochemical and gravimetric measurements. The corrosion product films were analyzed by scanning electron microscopy, energy-dispersive spectroscopy and x-ray diffraction. The presence of sulfide shifted the corrosion potential of Cu40Zn toward a more negative value by 100 mV and increased the mass loss rate by a factor of 1.257 compared with the result in the clean solution. The corrosion product film in the clean solution was thin and compact; it mainly consisted of oxides, such as ZnO and Cu2O. By contrast, the film in the sulfide-polluted solution was thick and porous. It mainly contained sulfides and zinc hydroxide chloride (i.e., Zn5(OH)8Cl2·H2O). The presence of sulfide ions accelerated the corrosion damage of Cu40Zn by hindering the formation of protective oxides and promoting the formation of a defective film which consisted of sulfides and hydroxide chlorides.
RECENT DEVELOPMENTS IN SRF CAVITY SCIENCE AND PERFORMANCE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gianluigi Ciovati
A recipe based on centrifugal barrel polishing (CBP) and electropolishing (EP), applied on newly designed single-cells, led to the achievement of B{sub p} values close to the thermodynamic critical field of Nb and to new records in terms of accelerating gradients The fabrication of cavities made of large-grain Nb is emerging as a viable option to reduce the material cost without sacrificing the performance. The Q-drop is not caused exclusively by losses at grain boundaries in Nb. Baking is the only known remedy against the Q-drop and its effect seems to be related to a change of the properties ofmore » the Nb up to a depth of about 20 nm. 120 C is the optimum temperature and the baking time can be reduced to 12 h. Cleaning techniques such as high-pressure rinse (HPR) are being studied in detail in order to be optimized for mass-production. Dry-ice cleaning may become a complementary cleaning method. Work is being done to better understand and to improve the EP process.« less
NASA Astrophysics Data System (ADS)
Carmona-Quiroga, P. M.; Martínez-Ramírez, S.; Viles, H. A.
2018-03-01
This study aimed to test the performance under long-term working conditions of a commercial self-cleaning coating, a water-based TiO2 sol, on three building materials important in recent and older European heritage; Portland limestone, Woodkirk sandstone and concrete. First, the compatibility of the coating (effect on petrophysical properties) with the substrates was demonstrated by examining aesthetic properties and water vapour permeability of the building materials and secondly, the self-cleaning ability of the TiO2 nanoparticles in degrading artificial stain (rhodamine B) under UV light was evaluated. Finally, the durability (lasting performance) of photocatalytic activity was assessed during one year of outdoor exposure trial and 2000 h of accelerated ageing in a chamber with UV radiation and condensation cycles. Results showed that photocatalytic activity was unaltered on concrete, whereas on sandstone, particularly after artificial ageing, it was reduced due to the removal of nanoparticles from the surface. On limestone, a decrease of TiO2 content was observed but photodegradation efficiency (ability to perform as self-cleaner) seemed not to be affected.
Technical specification for vacuum systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khaw, J.
The vacuum systems at the Stanford Linear Accelerator Center (SLAC) are primarily of all-metal construction and operate at pressures from 10/sup -5/ to 10/sup -11/ Torr. The primary gas loads during operation result from thermal desorption and beam-induced desorption from the vacuum chamber walls. These desorption rates can be extremely high in the case of hydrocarbons and other contaminants. These specifications place a major emphasis on eliminating contamination sources. The specifications and procedures have been written to insure the cleanliness and vacuum integrity of all SLAC vacuum systems, and to assist personnel involved with SLAC vacuum systems in choosing andmore » designing components that are compatible with existing systems and meet the quality and reliability of SLAC vacuum standards. The specification includes requirements on design, procurement, fabrication, chemical cleaning, clean room practices, welding and brazing, helium leak testing, residual gas analyzer testing, bakeout, venting, and pumpdown. Also appended are specifications regarding acceptable vendors, isopropyl alcohol, bakeable valve cleaning procedure, mechanical engineering safety inspection, notes on synchrotron radiation, and specifications of numerous individual components. (LEW)« less
Alloy Corrosion Considerations in Low-Cost, Clean Biomass Cookstoves for the Developing World
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brady, Michael P.; Banta, Kelly; Mizia, John
In nearly 40% of the world cooks on open fires or inefficient biomass-fueled cookstoves. The resulting smoke is a health hazard, contributing to an estimated 4 million premature deaths per year, as well as a major source of black carbon emissions. One solution is the introduction of improved, clean-burning biomass cookstoves. One of the most challenging components is the combustor, which must operate at high temperatures (often ≥ 600 °C) in the presence of highly corrosive species released from biomass fuel combustion, yet be sufficiently low cost to permit widespread adoption. In our present work we report the development ofmore » accelerated corrosion test screening protocols employing highly corrosive salt and water vapor species, specifically designed to evaluate alloys for clean biomass cookstove combustors, and corrosion findings for a range of commercial and developmental alloys. Lastly, a new Fe-Cr-Si base alloy that offers promise for improved corrosion resistance at lower cost than state-of the art FeCrAl and stainless steel alloys is also reported.« less
The hydrological consequences of human impact in the Lublin Region
NASA Astrophysics Data System (ADS)
Michalczyk, Zdzisław; Mięsiak-Wójcik, Katarzyna; Sposób, Joanna; Turczyński, Marek
2012-01-01
The Lublin Region is an area where local transformations in the natural environment, including the hydrosphere, occur. They result from the impact of agriculture, industry as well as water supply and sewage disposal. These activities lead to changes in the water network resulting from land improvement works, channel straightening and water runoff acceleration, as well as to the formation of local, both point and diffuse sources, of water pollution. The consequences of human impact are manifested in local transformations of the quality or quantity of water resources. As a result of intense groundwater draw-off, hydrogeological conditions are transformed, which is reflected in the persistence of depression cones of varied size and depth, noticeable in the vicinity of water intakes for Lublin, Chełm, Zamość and Kraśnik. The lowering of the first-level groundwater table also occurs as a consequence of the drainage of chalk and marl mine workings in Chełm and Rejowiec, whereas in the area of the hard coal mine both shallow and deep groundwater was transformed. It is important to indicate the consequences of human impact changes of water conditions as the hydrosphere resources should be used according to the principles of sustainable development.
Radio frequency multicusp ion source development (invited)
NASA Astrophysics Data System (ADS)
Leung, K. N.
1996-03-01
The radio-frequency (rf) driven multicusp source was originally developed for use in the Superconducting Super Collider injector. It has been demonstrated that the source can meet the H- beam current and emittance requirements for this application. By employing a porcelain-coated antenna, a clean plasma discharge with very long-life operation can be achieved. Today, the rf source is used to generate both positive and negative hydrogen ion beams and has been tested in various particle accelerator laboratories throughout the world. Applications of this ion source have been extended to other fields such as ion beam lithography, oil-well logging, ion implantation, accelerator mass spectrometry and medical therapy machines. This paper summarizes the latest rf ion source technology and development at the Lawrence Berkeley National Laboratory.
NASA Astrophysics Data System (ADS)
Gibson, J. Murray
2009-05-01
Probably the most prolific use of large accelerators today is in the creation of bright beams of x-ray photons or neutrons. The number of scientific users of such sources in the US alone is approaching 10,000. I will describe the some of the major applications of synchrotron and neutron radiation and their impact on society. If you have AIDS, need a better IPOD or a more efficient car, or want to clean up a superfund site, you are benefitting from these accelerators. The design of new materials is becoming more and more dependent on structural information from these sources. I will identify the trends in applications which are demanding new sources with greater capabilities.
Fabrication Technologies of the High Gradient Accelerator Structures at 100MV/M Range
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Juwen; /SLAC; Lewandowski, James
A CERN-SLAC-KEK collaboration on high gradient X-band structure research has been established in order to demonstrate the feasibility of the CLIC baseline design for the main linac stably operating at more than 100 MV/m loaded accelerating gradient. Several prototype CLIC structures were successfully fabricated and high power tested. They operated at 105 MV/m with a breakdown rate that meets the CLIC linear collider specifications of < 5 x 10{sup -7}/pulse/m. This paper summarizes the fabrication technologies including the mechanical design, precision machining, chemical cleaning, diffusion bonding as well as vacuum baking and all related assembly technologies. Also, the tolerances control,more » tuning and RF characterization will be discussed.« less
NASA Technical Reports Server (NTRS)
Bilwakesh, K. R.; Clemons, A.; Stimpert, D. L.
1979-01-01
Tests were run both in forward and in reverse thrust modes with a bellmouth inlet, five accelerating inlets (one hard wall and four treated) with a design throat Mach number of 0.79 at the takeoff condition, and four low Mach inlets (one hard wall and three treated) with a design throat Mach number of 0.6 at the takeoff condition. Unsuppressed and suppressed inlet radiated noise levels were measured at conditions representative of QCSEE takeoff, approach, and reverse thrust operations. Measured aerodynamic performance of the accelerating inlet is also included. The test objectives, facility, configurations, are described as well as the data analysis, results, and comparisons.
Pore Water PAH Transport in Amended Sediment Caps
NASA Astrophysics Data System (ADS)
Gidley, P. T.; Kwon, S.; Ghosh, U.
2009-05-01
Capping is a common remediation strategy for contaminated sediments that creates a physical barrier between contaminated sediments and the water column. Diffusive flux of contaminants through a sediment cap is small. However, under certain hydrodynamic conditions such as groundwater potential and tidal pumping, groundwater advection can accelerate contaminant transport. Hydrophobic organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) could be transported through the cap under advective conditions. To better understand PAH migration under these conditions, physical models of sediment caps were evaluated in the laboratory through direct measurement of pore water using solid phase micro-extraction with gas chromatography and mass spectrometry. Contaminated sediment and capping material was obtained from an existing Superfund site that was capped at Eagle Harbor, Washington. A PAH dissolution model linked to an advection-dispersion equation with retardation using published organic carbon-water partitioning coefficients (Koc) was compared to measured PAHs in the sediment and cap porewater of the physical model.
Effects of suburban development on runoff generation in the Croton River basin, New York, USA
Burns, D.; Vitvar, T.; McDonnell, J.; Hassett, J.; Duncan, J.; Kendall, C.
2005-01-01
The effects of impervious area, septic leach-field effluent, and a riparian wetland on runoff generation were studied in three small (0.38-0.56 km 2) headwater catchments that represent a range of suburban development (high density residential, medium density residential, and undeveloped) within the Croton River basin, 70 km north of New York City. Precipitation, stream discharge, and groundwater levels were monitored at 10-30 min intervals for 1 year, and stream water and groundwater samples were collected biweekly for ??18O, NO3-, and SO42- analysis for more than 2 years during an overlapping period in 2000-2002. Data from 27 storms confirmed that peak magnitudes increased and recession time decreased with increasing development, but lags in peak arrival and peak discharge/mean discharge were greatest in the medium density residential catchment, which contains a wetland in which storm runoff is retained before entering the stream. Baseflow during a dry period from Aug. 2001-Feb. 2002 was greatest in the high-density residential catchment, presumably from the discharge of septic effluent through the shallow groundwater system and into the stream. In contrast, moderate flows during a wet period from Mar.-Aug. 2002 were greatest in the undeveloped catchment, possibly as a result of greater subsurface storage or greater hydraulic conductivity at this site. The mean residence time of baseflow was about 30 weeks at all three catchments, indicating that human influence was insufficient to greatly affect the groundwater recharge and discharge properties that determine catchment residence time. These results suggest that while suburban development and its associated impervious surfaces and storm drains accelerate the transport of storm runoff into streams, the combined effects of remnant natural landscape features such as wetlands and human alterations such as deep groundwater supply and septic systems can change the expected effects of human development on storm runoff and groundwater recharge. ?? 2005 Elsevier B.V. All rights reserved.
Modeling rock weathering in small watersheds
NASA Astrophysics Data System (ADS)
Pacheco, Fernando A. L.; Van der Weijden, Cornelis H.
2014-05-01
Many mountainous watersheds are conceived as aquifer media where multiple groundwater flow systems have developed (Tóth, 1963), and as bimodal landscapes where differential weathering of bare and soil-mantled rock has occurred (Wahrhaftig, 1965). The results of a weathering algorithm (Pacheco and Van der Weijden, 2012a, 2014), which integrates topographic, hydrologic, rock structure and chemical data to calculate weathering rates at the watershed scale, validated the conceptual models in the River Sordo basin, a small watershed located in the Marão cordillera (North of Portugal). The coupling of weathering, groundwater flow and landscape evolution analyses, as accomplished in this study, is innovative and represents a remarkable achievement towards regionalization of rock weathering at the watershed scale. The River Sordo basin occupies an area of approximately 51.2 km2 and was shaped on granite and metassediment terrains between the altitudes 185-1300 m. The groundwater flow system is composed of recharge areas located at elevations >700 m, identified on the basis of δ18O data. Discharge cells comprehend terminations of local, intermediate and regional flow systems, identified on the basis of spring density patterns, infiltration depth estimates based on 87Sr/86Sr data, and spatial distributions of groundwater pH and natural mineralization. Intermediate and regional flow systems, defined where infiltration depths >125 m, develop solely along the contact zone between granites and metassediments, because fractures in this region are profound and their density is very large. Weathering is accelerated where rocks are covered by thick soils, being five times faster relative to sectors of the basin where rocks are covered by thin soils. Differential weathering of bare and soil-mantled rock is also revealed by the spatial distribution of calculated aquifer hydraulic diffusivities and groundwater travel times.
The EM SSAB Annual Work Plan Process: Focusing Board Efforts and Resources - 13667
DOE Office of Scientific and Technical Information (OSTI.GOV)
Young, Ralph
One of the most daunting tasks for any new member of a local board of the Environmental Management Site Specific Advisory Board (EM SSAB) is to try to understand the scope of the clean-up activities going on at the site. In most cases, there are at least two or three major cleanup activities in progress as well as monitoring of past projects. When planning for future projects is added to the mix, the list of projects can be long. With the clean-up activities involving all major environmental media - air, water, soils, and groundwater, new EM SSAB members can findmore » themselves totally overwhelmed and ineffective. Helping new members get over this initial hurdle is a major objective of EM and all local boards of the EM SSAB. Even as members start to understand the size and scope of the projects at a site, they can still be frustrated at the length of time it takes to see results and get projects completed. Many project and clean-up timelines for most of the sites go beyond 10 years, so it's not unusual for an EM SSAB member to see the completion of only 1 or 2 projects over the course of their 6-year term on the board. This paper explores the annual work planning process of the EM SSAB local boards, one tool that can be used to educate EM SSAB members into seeing the broader picture for the site. EM SSAB local work plans divide the site into projects focused on a specific environmental issue or media such as groundwater and/or waste disposal options. Projects are further broken down into smaller segments by highlighting major milestones. Using these metrics, local boards of the EM SSAB can start to quantify the effectiveness of the project in achieving the ultimate goal of site clean-up. These metrics can also trigger board advice and recommendations for EM. At the beginning of each fiscal year, the EM SSAB work plan provides a road map with quantifiable checkpoints for activities throughout the year. When the work plans are integrated with site-specific, enforceable regulatory milestones, they can provide a comprehensive work plan for not only the board, but also regulators, site contractors, and DOE. Because the work plans are reviewed and approved by DOE, they carry some weight in holding local boards of the EM SSAB accountable. This structure provides the basis for local boards to achieve their primary function, to provide DOE with information, advice, and recommendations concerning issues affecting the EM program at the site. (authors)« less
NASA Technical Reports Server (NTRS)
Predmore, Roamer; LeBoeuf, Claudia; Hovanec, Andrew
1997-01-01
In response to the elimination of production of several Ozone Depleting Chemicals (ODC's) which have been widely used in successful space flight mechanism cleaning and lubricating procedures, GSFC developed and implemented an overall philosophy of mitigating the risks to flight hardware during the transition phase to ODC-free cleaning procedures. The short term leg of the philosophy was the stockpiling of an appropriate amount of ODC solvents such that all short term GSFC missions will be able to stay with or revert to heritage cleaning and lubricating procedures in the face of life issues. The long-term leg of that philosophy was the initiation of a several tier testing program that will deliver increasing amounts of information over the next few years, starting with accelerated lubricant life tests that compare lubricant life on surfaces cleaned with ODC solvents with lubricant life on surfaces cleaned with ODC-free solvents. While tribological testing, mechanism life testing and space-flight experience will ultimately bring us into the 21st century with environmentally friendly means of cleaning long-life precision mechanism components, many satellites will be launched over the next few years before a number of important tribological questions can be answered. In order to prepare for this challenge, the Materials Engineering Branch in cooperation with the Electromechanical Branch launched an intensive review of all ongoing missions. The failure risk was determined for each long-life lubricated mechanism based on a number of parameters, including 4 comparison of flight solvents used to clean the heritage/life test hardware. Also studied was the ability of the mechanism manufacturers to stockpile ODC's based on state laws and company policies. A stockpiling strategy was constructed based on this information and subsequently implemented. This paper provides an overview of the GSFC ODC elimination risk mitigation philosophy as well as a detailed examination of the development of the ODC stockpiling plan.
Nickels, Janet S.; Bobbie, Ronald J.; Lott, Dan F.; Martz, Robert F.; Benson, Peter H.; White, David C.
1981-01-01
Metals exposed to rapidly flowing seawater are fouled by microbes that increase heat transfer resistance. In this study, results of biochemical test methods quantitatively relating the biomass and community structure of the microfouling film on aluminum and titanium to heat transfer resistance across the metal surface during three cycles of free fouling and manual brushing showed that cleaning accelerates the rate of fouling measured as the loss of heat transfer efficiency and as microfouling film biomass. The results also showed that the rate of fouling, measured as an increase in heat transfer resistance, is faster on titanium than on aluminum but that the titanium surface is more readily cleaned. In three cycles of free fouling and cleaning with a stiff-bristle nylon brush, the free-fouling communities re-forming on aluminum became enriched in bacteria containing short-branched fatty acids as the cycling progressed. The free-fouling community on titanium revealed an increasingly diverse morphology under scanning electron microscopy that was enriched in a portion of the microeucaryotes. Brushing removed most of the biomass, but left a residual community that was relatively enriched in a portion of the bacterial assembly containing cyclopropane fatty acids on aluminum and in a more diverse community on the titanium surface. The residual communities left after cleaning of titanium revealed an increase in bacteria with short-branched fatty acids and in microeucaryotes as cleaning continued. No significant changes occurred in the residual microbial community structure left on aluminum with cleaning; it was, again, less diverse than that remaining on titanium. The residual communities secreted a twofold-larger amount of extracellular polymer, measured as the ratio of total organic carbon to lipid phosphate, than did the free-fouling community on both surfaces. Images PMID:16345798
NASA Astrophysics Data System (ADS)
Brusseau, Mark L.; Guo, Zhilin
2018-01-01
It is evident based on historical data that groundwater contaminant plumes persist at many sites, requiring costly long-term management. High-resolution site-characterization methods are needed to support accurate risk assessments and to select, design, and operate effective remediation operations. Most subsurface characterization methods are generally limited in their ability to provide unambiguous, real-time delineation of specific processes affecting mass-transfer, transformation, and mass removal, and accurate estimation of associated rates. An integrated contaminant elution and tracer test toolkit, comprising a set of local-scale groundwater extraction-and injection tests, was developed to ameliorate the primary limitations associated with standard characterization methods. The test employs extended groundwater extraction to stress the system and induce hydraulic and concentration gradients. Clean water can be injected, which removes the resident aqueous contaminant mass present in the higher-permeability zones and isolates the test zone from the surrounding plume. This ensures that the concentrations and fluxes measured within the isolated area are directly and predominantly influenced by the local mass-transfer and transformation processes controlling mass removal. A suite of standard and novel tracers can be used to delineate specific mass-transfer and attenuation processes that are active at a given site, and to quantify the associated mass-transfer and transformation rates. The conceptual basis for the test is first presented, followed by an illustrative application based on simulations produced with a 3-D mathematical model and a brief case study application.
NASA Astrophysics Data System (ADS)
Legowo, Budi; Darsono; Wahyuningsih, Daru
2016-11-01
Changes in land use for housing indirectly disturb the hydrology balance of the area. Groundwater conservation efforts can be done by keeping the function the catchment area. One of the housing developer's obligations is providing open spaces (the playground) to play or activity of the residents. Playground in Bumi Graha Indah Housing, Jaten village, Karanganyar district, Central Java, Indonesia has a fundamental issue, that is, in the rainy season the water is difficult to seep due landfill process are not well planned. It causes the playground become in muddy conditions with tall grass, so that reduces the function as a playground and or activity the residents. In the dry season, the soil dry of landfill caused dust scattering and disrupt the activities of people around the playground. Lack of water resources lead watering process for solving the problem of dust during the dry season was considered ineffective. Structuring drainage combined with modified recharge wells can be used to catch water runoff housing. This modification of water catchment areas can make playground dry quickly after rain so the activities of people are not bothered when utilizing the open space provided. Surface runoff water absorbed in open aquifer so that the hydrological balance always be maintained. Adequacy groundwater in the area playground can be used to sprinkler dust and backup needs clean water residents by creating wells and reservoir stocks.
NASA Astrophysics Data System (ADS)
Park, C.; Lee, J.; Koo, M.
2011-12-01
Climate is the most critical driving force of the hydrologic system of the Earth. Since the industrial revolution, the impacts of anthropogenic activities to the Earth environment have been expanded and accelerated. Especially, the global emission of carbon dioxide into the atmosphere is known to have significantly increased temperature and affected the hydrologic system. Many hydrologists have contributed to the studies regarding the climate change on the hydrologic system since the Intergovernmental Panel on Climate Change (IPCC) was created in 1988. Among many components in the hydrologic system groundwater and its response to the climate change and anthropogenic activities are not fully understood due to the complexity of subsurface conditions between the surface and the groundwater table. A new spatio-temporal hydrologic model has been developed to estimate the impacts of climate change and land use dynamics on the groundwater. The model consists of two sub-models: a surface model and a subsurface model. The surface model involves three surface processes: interception, runoff, and evapotranspiration, and the subsurface model does also three subsurface processes: soil moisture balance, recharge, and groundwater flow. The surface model requires various input data including land use, soil types, vegetation types, topographical elevations, and meteorological data. The surface model simulates daily hydrological processes for rainfall interception, surface runoff varied by land use change and crop growth, and evapotranspiration controlled by soil moisture balance. The daily soil moisture balance is a key element to link two sub-models as it calculates infiltration and groundwater recharge by considering a time delay routing through a vadose zone down to the groundwater table. MODFLOW is adopted to simulate groundwater flow and interaction with surface water components as well. The model is technically flexible to add new model or modify existing model as it is developed with an object-oriented language - Python. The model also can easily be localized by simple modification of soil and crop properties. The actual application of the model after calibration was successful and results showed reliable water balance and interaction between the surface and subsurface hydrologic systems.
Monirul Islam, Md; Kanungoe, P
2005-01-01
This paper presents the results of water balance study and aquifer simulation modeling for preliminary estimation of the recharge rate and sustainable yield for the semi arid Barind Tract region of Bangladesh. The outcomes of the study are likely to be useful for planning purposes. It is found from detailed water balance study for the area that natural recharge rates in the Barind Tract vary widely year to year. It may have resulted from the method used for the calculation. If the considered time interval had been smaller than the monthly rainfall, the results could have been different. Aquifer Simulation Modeling (ASM) for the Barind aquifer is used to estimate long-term sustainable yield of the groundwater considering limiting drawdown from the standpoint of economic pumping cost. In managing a groundwater basin efficiently and effectively, evaluation of the maximum annual groundwater yield of the basin that can be withdrawn and used without producing any undesirable effect is one of the most important issues. In investigating such recharge rate, introduction of certain terms such as sustainable yield and safe yield has been accompanied. Development of this area involves proper utilization of this vast land, which is possible only through ensured irrigation for agriculture. The Government of Bangladesh has a plan to develop irrigation facilities by optimum utilization of available ground and surface water. It is believed that the groundwater table is lowering rapidly and the whole region is in an acute state of deforestation. Indiscriminate groundwater development may accelerate deforestation trend. In this context estimation of actual natural recharge rate to the aquifer and determination of sustainable yield will assist in proper management and planning of environmentally viable abstraction schemes. It is revealed from the study that the sustainable yield of ground water (204 mm/y) is somewhat higher than the long-term annual average recharge (152.7 mm) to the groundwater reservoir. The reason behind this is that the rivers within and around the Barind Tract might have played the role of influent rivers.
NASA Astrophysics Data System (ADS)
Glas, R. L.; Lautz, L.; McKenzie, J. M.; Moucha, R.; Mark, B. G.
2017-12-01
Geological and depositional conditions of the glaciated Cordillera Blanca in Peru have given way to proglacial aquifer systems that contribute substantially to regional streams and rivers, particularly during the dry season. As glacial retreat accelerates, the dry season water budget will be increasingly dominated by groundwater inputs, although predictions of future groundwater quantities require estimations of groundwater storage capacity, aquifer extents, and groundwater residence time. We present a characterization of the sediment structure in a prototypical proglacial valley in the central portion of the range, the Quilcayhuanca Valley. Northern and Central valleys of the Cordillera Blanca feature ubiquitous talus deposits that line the steep granite walls, and have become partially buried beneath lacustrine sediments deposited in proglacial lake beds. The portion of the talus still exposed near the valley walls provides recharge to deeper portions of the valley aquifers that underlie lacustrine clay, resulting in a confined aquifer system that is connected to the surface via perennial springs. Seismic refraction surveys reveal an interface separating relatively slow ( 400-800 m/s) and fast ( 2500 m/s) p-wave velocities. The depth of this refractor coincides with the depth to buried talus observed in drilling records. Electrical resistivity tomography profiles of the same transect show depths near the buried talus to be relatively conductive (10-100 Ωm). At these depths, we hypothesize that electrical conductance is elevated by saturated clay particles in the sediment matrix of the talus deposit. The resistivity models all show a more resistive ( 700 Ω m) region at depth, likely corresponding to a more hydraulically conductive material. The resistive zone is interpreted to be a deeper portion of a buried talus deposit that did not accumulate clay in the matrix. Other possibilities include a thick deposit of gravelly glacial outwash, or a relatively clay-poor glacial till. We present a groundwater modeling framework to resolve the nature of the sediments in deeper layers, where geophysical data become less certain. Sediment permeability estimates will allow for more refined predictions of groundwater storage volume in buried talus aquifers, which are likely prevalent throughout the range.
Factors limiting sulfolane biodegradation in contaminated subarctic aquifer substrate.
Kasanke, Christopher P; Leigh, Mary Beth
2017-01-01
Sulfolane, a water-soluble organosulfur compound, is used industrially worldwide and is associated with one of the largest contaminated groundwater plumes in the state of Alaska. Despite being widely used, little is understood about the degradation of sulfolane in the environment, especially in cold regions. We conducted aerobic and anaerobic microcosm studies to assess the biological and abiotic sulfolane degradation potential of contaminated subarctic aquifer groundwater and sediment from Interior Alaska. We also investigated the impacts of nutrient limitations and hydrocarbon co-contamination on sulfolane degradation. We found that sulfolane underwent biodegradation aerobically but not anaerobically under nitrate, sulfate, or iron-reducing conditions. No abiotic degradation activity was detectable under either oxic or anoxic conditions. Nutrient addition stimulated sulfolane biodegradation in sediment slurries at high sulfolane concentrations (100 mg L-1), but not at low sulfolane concentrations (500 μg L-1), and nutrient amendments were necessary to stimulate sulfolane biodegradation in incubations containing groundwater only. Hydrocarbon co-contamination retarded aerobic sulfolane biodegradation rates by ~30%. Our study is the first to investigate the sulfolane biodegradation potential of subarctic aquifer substrate and identifies several important factors limiting biodegradation rates. We concluded that oxygen is an important factor limiting natural attenuation of this sulfolane plume, and that nutrient amendments are unlikely to accelerate biodegradation within in the plume, although they may biostimulate degradation in ex situ groundwater treatment applications. Future work should be directed at elucidating the identity of indigenous sulfolane-degrading microorganisms and determining their distribution and potential activity in the environment.
NASA Astrophysics Data System (ADS)
Tavakoly, A. A.; Habets, F.; Saleh, F.; Yang, Z. L.
2017-12-01
Human activities such as the cultivation of N-fixing crops, burning of fossil fuels, discharging of industrial and domestic effluents, and extensive usage of fertilizers have recently accelerated the nitrogen loading to watersheds worldwide. Increasing nitrate concentration in surface water and groundwater is a major concern in watersheds with extensive agricultural activities. Nutrient enrichment is one of the major environmental problems in the French coastal zone. To understand and predict interactions between agriculture, surface water and groundwater nitrate contaminants, this study presents a modeling framework that couples the agronomic STICS model with Eau-Dyssée, a distributed hydrologic modeling system to simulate groundwater-surface water interaction. The coupled system is implemented on the Seine River Basin with an area of 88,000 km2 to compute daily nitrate contaminants. Representing a sophisticated hydrosystem with several aquifers and including the megalopolis of Paris, the Seine River Basin is well-known as one of the most productive agricultural areas in France. The STICS-EauDyssée framework is evaluated for a long-term simulation covering 39 years (1971-2010). Model results show that the simulated nitrate highly depends on the inflow produced by surface and subsurface waters. Daily simulation shows that the model captures the seasonal variation of observations and that the overall long-term simulation of nitrate contaminant is satisfactory at the regional scale.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ferris, F. Grant; Fujita, Yoshiko; Smith, Robert W.
2004-06-15
Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) weapons complex. In situ containment and stabilization of these contaminants in vadose zones or groundwater is a cost-effective treatment strategy. Our facilitated approach relies upon the hydrolysis of introduced urea to cause the acceleration of calcium carbonate precipitation (and trace metal coprecipitation) by increasing groundwater pH and alkalinity (Fujita et al., 2000; Warren et al., 2001). Subsurface urea hydrolysis is catalyzed by the urease enzyme, which may be either introduced with the urea or produced in situ by ubiquitous subsurface ureamore » hydrolyzing microorganisms. Because the precipitation processes are irreversible and many western aquifers are saturated with respect to calcite, the co-precipitated metals and radionuclides will be effectively removed from groundwater. The rate at which trace metals are incorporated into calcite is a function of calcite precipitation kinetics, adsorption interactions between the calcite surface and the trace metal in solution (Zachara et al., 1991), solid solution properties of the trace metal in calcite (Tesoriero and Pankow, 1996), and also the surfaces upon which the calcite is precipitating. A fundamental understanding of the coupling of calcite precipitation and trace metal partitioning, and how this occurs in aquifers and vadose environments is lacking. This report summarizes work undertaken during the second year of this project.« less
Factors limiting sulfolane biodegradation in contaminated subarctic aquifer substrate
2017-01-01
Sulfolane, a water-soluble organosulfur compound, is used industrially worldwide and is associated with one of the largest contaminated groundwater plumes in the state of Alaska. Despite being widely used, little is understood about the degradation of sulfolane in the environment, especially in cold regions. We conducted aerobic and anaerobic microcosm studies to assess the biological and abiotic sulfolane degradation potential of contaminated subarctic aquifer groundwater and sediment from Interior Alaska. We also investigated the impacts of nutrient limitations and hydrocarbon co-contamination on sulfolane degradation. We found that sulfolane underwent biodegradation aerobically but not anaerobically under nitrate, sulfate, or iron-reducing conditions. No abiotic degradation activity was detectable under either oxic or anoxic conditions. Nutrient addition stimulated sulfolane biodegradation in sediment slurries at high sulfolane concentrations (100 mg L-1), but not at low sulfolane concentrations (500 μg L-1), and nutrient amendments were necessary to stimulate sulfolane biodegradation in incubations containing groundwater only. Hydrocarbon co-contamination retarded aerobic sulfolane biodegradation rates by ~30%. Our study is the first to investigate the sulfolane biodegradation potential of subarctic aquifer substrate and identifies several important factors limiting biodegradation rates. We concluded that oxygen is an important factor limiting natural attenuation of this sulfolane plume, and that nutrient amendments are unlikely to accelerate biodegradation within in the plume, although they may biostimulate degradation in ex situ groundwater treatment applications. Future work should be directed at elucidating the identity of indigenous sulfolane-degrading microorganisms and determining their distribution and potential activity in the environment. PMID:28727811
Schumacher, John G.; Struckhoff, Garrett C.; Burken, Joel G.
2004-01-01
Tree-core sampling has been a reliable and inexpensive tool to quickly assess the presence of shallow (less than about 30 feet deep) tetrachloroethene (PCE) and trichloroethene (TCE) contamination in soils and ground water at the Riverfront Superfund Site. This report presents the results of tree-core sampling that was successfully used to determine the presence and extent of chlorinated solvent contamination at two sites, the Front Street site (operable unit OU1) and the former dry cleaning facility, that are part of the overall Riverfront Superfund Site. Traditional soil and ground-water sampling at these two sites later confirmed the results from the tree-core sampling. Results obtained from the tree-core sampling were used to design and focus subsequent soil and ground-water investigations, resulting in substantial savings in time and site assessment costs. The Front Street site is a small (less than 1-acre) site located on the Missouri River alluvium in downtown New Haven, Missouri, about 500 feet from the south bank of the Missouri River. Tree-core sampling detected the presence of subsurface PCE contamination at the Front Street site and beneath residential property downgradient from the site. Core samples from trees at the site contained PCE concentrations as large as 3,850 mg-h/kg (micrograms in headspace per kilogram of wet core) and TCE concentrations as large as 249 mg-h/kg. Soils at the Front Street site contained PCE concentrations as large as 6,200,000 mg/kg (micrograms per kilogram) and ground-water samples contained PCE concentrations as large as 11,000 mg/L (micrograms per liter). The former dry cleaning facility is located at the base of the upland that forms the south bank of the Missouri River alluvial valley. Tree-core sampling did not indicate the presence of PCE or TCE contamination at the former dry cleaning facility, a finding that was later confirmed by the analyses of soil samples collected from the site. The lateral extent of PCE contamination in trees was in close agreement with the extent of subsurface PCE contamination determined using traditional soil and ground-water sampling methods. Trees growing in soils containing PCE concentrations of 60 to 5,700 mg/kg or larger or overlying ground water containing PCE concentrations from 5 to 11,000 mg/L generally contained detectable concentrations of PCE. The depth to contaminated ground water was about 20 to 25 feet below the land surface. Significant quantitative relations [probability (p) values of less than 0.05 and correlation coefficient (r2) values of 0.88 to 0.90] were found between PCE concentrations in trees and subsurface soils between 4 and 16 feet deep. The relation between PCE concentrations in trees and underlying ground water was less apparent (r2 value of 0.17) and the poor relation is thought to be the result of equilibrium with PCE concentrations in soil and vapor in the unsaturated zone. Based on PCE concentrations detected in trees at the Front Street site and trees growing along contaminated tributaries in other operable units, and from field hydroponic experiments using hybrid poplar cuttings, analysis of tree-core samples appears to be able to detect subsurface PCE contamination in soils at levels of several hundred micrograms per liter or less and PCE concentrations in the range of 8 to 30 mg/L in ground water in direct contact with the roots. Loss of PCE from tree trunks by diffusion resulted in an exponential decrease in PCE concentrations with increasing height above the land surface in most trees. The rate of loss also appeared to be a function of the size and growth characteristics of the tree as some trees exhibited a linear loss with increasing height. Diffusional loss of PCE in small (0.5-inch diameter) trees was observed to occur at a rate more than 10 times larger than in trees 6.5 inches in diameter. Concentrations of PCE also exhibited directional variability around the tree trunks and concentration differe
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
The 21st Century Power Partnership's program in Mexico (21CPP Mexico) is one initiative of the Clean Energy Ministerial carried out in cooperation with government and local stakeholders, drawing upon an international community of power system expertise.The overall goal of this program is to support Mexico's power system transformation by accelerating the transition to a reliable, financially robust, and low-carbon system.
NASA Helps Build Colorado Economy
2010-12-13
Colorado State Governor Bill Ritter delivers remarks at the Colorado State Capitol in Denver on Monday, Dec. 13, 2010, prior to the signing of an agreement with NASA that creates a Technology Acceleration Program and Regional Innovation Cluster for Aerospace and Clean Energy. A manufacturing park focused on rapid new product development and production will be developed to assist growing Colorado businesses while promoting the commercialization of technology developed for the space program. Photo Credit: (NASA/Bill Ingalls)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smyth, David; Roos, Gillian; Ferguson Jones, Andrea
2013-07-01
The Highland Drive South Ravine (HDSR) is the discharge area for groundwater originating from the Highland Drive Landfill, the Pine Street North Extension (PSNE) roadbed parts of the Highland Drive roadbed and the PSNE Consolidation Site that contain historical low-level radioactive waste (LLRW). The contaminant plume from these LLRW sites contains elevated concentrations of uranium and arsenic and discharges with groundwater to shallow soils in a wet discharge area within the ravine, and directly to Hunt's Pond and Highland Drive South Creek, which are immediately to the south of the wet discharge area. Remediation and environmental management plans for HDSRmore » have been developed within the framework of the Port Hope Project and the Port Hope Area Initiative. The LLRW sites will be fully remediated by excavation and relocation to a new Long-Term Waste Management Facility (LTWMF) as part of the Port Hope Project. It is projected, however, that the groundwater contaminant plume between the remediated LLRW sites and HDSR will persist for several hundreds of years. At the HDSR, sediment remediation within Hunt's Ponds and Highland Drive South Creek, excavation of the existing and placement of clean fill will be undertaken to remove current accumulations of solid-phase uranium and arsenic associated with the upper 0.75 m of soil in the wet discharge area, and permeable reactive barriers (PRBs) will be used for in situ treatment of contaminated groundwater to prevent the ongoing discharge of uranium and arsenic to the area in HDSR where shallow soil excavation and replacement has been undertaken. Bench-scale testing using groundwater from HDSR has confirmed excellent treatment characteristics for both uranium and arsenic using permeable reactive mixtures containing granular zero-valent iron (ZVI). A sequence of three PRBs containing ZVI and sand in backfilled trenches has been designed to intercept the groundwater flow system prior to its discharge to the ground surface and the creek and ponds in the HDSR. The first of the PRBs will be installed immediately up-gradient of the wet discharge area approximately 50 m from the creek, the other two will be installed across the area of shallow soil replacement, and all will extend from ground surface to the base of the water table aquifer through which the impacted groundwater flows. The PRBs have been designed to provide the removal of uranium and arsenic for decades, although the capacity of the treatment mixture for contaminant removal suggests that a longer period of treatment may be feasible. The environmental management plan includes an allowance for on-going monitoring, and replacement of a PRB(s) as might be required. (authors)« less
Investigating Groundwater Depletion and Aquifer Degradation in Central Valley California from Space
NASA Astrophysics Data System (ADS)
Ojha, C.; Shirzaei, M.; Werth, S.; Argus, D. F.
2017-12-01
The Central Valley in California includes one of the world's largest and yet most stressed aquifer systems. The large demand for groundwater, accelerated by population growth and extreme droughts, has been depleting the region's groundwater resources for decades. However, the lack of dense monitoring networks and inaccurate information on geophysical aquifer response pose serious challenges to water management efforts in the area and put the groundwater at high risk. Here, we performed a joint analysis of large SAR interferometric data sets acquired by ALOS L-band satellite in conjunction with the groundwater level observations across the Central Valley. We used 420 L-band SAR images acquired on the ascending orbit track during period Dec 24, 2006 - Jan 1, 2010, and generated more than 1600 interferograms with a pixel size of 100 m × 100 m. We also use data from 1600 observational wells providing continuous measurements of groundwater level within the study period for our analysis. We find that in the south and near Tulare Lake, north of Tule and south of Kaweah basin in San Joaquin valley, the subsidence rate is greatest at up to 20-25 cm/yr, while in Sacramento Valley the subsidence rate is lower at 1-3 cm/yr. From the characterization of the elastic and inelastic storage coefficients, we find that Kern, Tule, Tulare, Kaweah and Merced basins in the San Joaquin Valley are more susceptible to permanent compaction and aquifer storage loss. Kern County shows 0.23%-1.8% of aquifer storage loss during the study period, and has higher percentage loss than adjacent basins such as Tule and Tulare Lake with 0.15%-1.2% and 0.2 %-1.5% loss, respectively. Overall, we estimate that the aquifers across the valley lost a total of 28 km3 of groundwater and 2% of their storage capacity during the study period. Our unique observational evidence including valley-wide estimate of mechanical properties of aquifers and model results will not only facilitate monitoring water deficits and estimating water storage variations, but is also useful to water managers, policy makers, and the communities living in water-stressed regions for development and management plans. Ongoing analysis using data from Envisat, Sentinel-1 and Radarasat-1 satellites will further play a key role is characterizing the evolution of groundwater resources.
NASA Astrophysics Data System (ADS)
Aquilina, Luc; Marçais, Jean; de Dreuzy, Jean-Raynald; Labasque, Thierry; Abbott, Ben; Vergnaud, Virginie; Walter, Christian; Viville, Daniel; Chabaux, François; Pinay, Gilles
2017-04-01
Agricultural pollution is a matter of political and scientific concern throughout the world. Intensive agriculture can cause nutrient contamination of groundwater and surface water. Nutrient pollution causes eutrophication in freshwater and estuarine ecosystems. A secondary effect of agricultural intensification is river acidification. Oxidation of chemical fertilizers such as ammonium (NH4+) to nitrate (NO3-) produces H+ ions that cause leaching of cations from soil and deeper material to maintain charge balance. Monitoring of various rivers in Brittany (western France) revealed that agriculture intensification has led to increased cation export starting in the 1980s. From the cation ratios, we deduced that cation increase comes approximately equally from dissolution of carbonate added to soil (liming practices) and silicate dissolution. Cation export represented about 30% of the soil cation exchange potential. If compensated by liming, it may constitute a non-negligible source to atmospheric CO2 (Aquilina et al., 2012). We further investigated the potential for silicate dissolution through the use of groundwater dating in various sites of Brittany. Coupling chemical analyses to groundwater ages in a large range of aquifers and a large range of depths (down to 110m) allowed us to reconstruct a chronicle for the last 50 yrs of the cation concentrations of groundwater. It clearly shows a contemporaneous increase in sodium and nitrate and a decrease in calcium, with the most dramatic changes occurring during the 70s and 80s. Using groundwater dating, we were also able to determine a silica production geochronometer. A tight and linear relationship between silica concentration and groundwater age (Figure) was observed and allowed a production rate in groundwater to be determined. Except for short residence-times (Kerrien), the silica production rate for different granitic catchments was consistent, ranging from 0.3 to 0.4 mg.L-1.yr-1. To assess the role of anthropogenic activity in silica production rate, we compared production rates from Brittany with catchments in the Vosges Mountains, a relatively pristine area. Dissolution rates were much higher in the Brittany catchments, indicating the effect of human activities on chemical weathering and cation export at the catchment scale. Aquilina L. et al., 2012 - Long-term effects of high nitrogen loads on cation and carbon riverine export in agricultural catchments. Env. Sci & Technology 46-17, 9447-9455..
Antimicrobial Efficacy of Contact Lens Care Solutions Against Neutrophil-Enhanced Bacterial Biofilms
Hinojosa, Jorge A.; Patel, Naiya B.; Zhu, Meifang; Robertson, Danielle M.
2017-01-01
Purpose Neutrophil-derived extracellular debris has been shown to accelerate bacterial biofilm formation on hydrogel and silicone hydrogel contact lens surfaces compared to lenses inoculated with bacteria alone. The purpose of this study was to evaluate the disinfection efficacy of four standard commercial contact lens cleaning regimens against neutrophil-enhanced bacterial biofilms formed on silicone hydrogel contact lenses. Methods Four reference strains were used: Pseudomonas aeruginosa, Serratia marcescens, Stenotrophomonas maltophilia, and Staphylococcus aureus. Human neutrophils were isolated from peripheral blood by venipuncture. Unworn Lotrafilcon B lenses were incubated overnight in each respective strain with stimulated neutrophils. Contact lenses were then cleaned using one of four contact lens care solutions according to manufacturer instructions. Bacterial viability was assessed by colony counts and confocal microscopy. Volume of residual debris on lens surfaces after cleaning was quantified using IMARIS software. Results All four solutions tested showed effective antimicrobial activity against each bacterial strain; however, substantial amounts of nonviable bacteria and cellular debris remained on the lens surface despite concomitant digital cleaning. Conclusions Necrotic cellular debris that accumulates under the posterior lens surface during wear of an inoculated contact lens is not fully removed during routine cleaning and disinfection. Translational Relevance The accumulation of residual cellular debris on the contact lens surface may contribute to new colonization of the lens and represents a significant risk factor for a contact lens–related adverse event. Additional studies are needed to correlate these findings with risk for corneal infiltrative and/or infectious events in a standard animal model. PMID:28473944
Imbalance in Groundwater-Surface Water Interactions and its Relationship to the Coastal Zone Hazards
NASA Astrophysics Data System (ADS)
Kontar, Y. A.; Ozorovich, Y. R.; Salokhiddinov, A. T.
2011-12-01
We report here some efforts and results in studying the imbalance in groundwater-surface water interactions and processes of groundwater-surface water interactions and groundwater flooding creating hazards in the coastal zones. Hazards, hydrological and geophysical risk analysis related to imbalance in groundwater-surface water interactions and groundwater flooding have been to a large extent under-emphasized for coastal zone applications either due to economical limitations or underestimation of significance of imbalance in groundwater-surface water interactions. This is particularly true for tsunamis creating salt water intrusion to coastal aquifers, even though most tsunami hazard assessments have in the past relied on scenario or deterministic type models, and to increasing mineralization of potable water because of intensive water diversions and also the abundance of highly toxic pollutants (mainly pesticides) in water, air and food, which contribute to the deterioration of the coastal population's health. In the wake of pressing environmental and economic issues, it is of prime importance for the scientific community to shed light onto the great efforts by hydrologists and geophysicists to quantify conceptual uncertainties and to provide quality assurances of potential coastal zone hazard evaluation and prediction under conditions of imbalance in groundwater-surface water interactions. This paper proposes consideration of two case studies which are important and significant for future understanding of a concept of imbalance in groundwater-surface water interactions and development and essential for feasibility studies of hazards in the coastal zone. The territory of the Aral Sea Region in Central Asia is known as an ecological disaster coastal zone. It is now obvious that, in order to provide reasonable living conditions to the coastal zone population, it is first of all necessary to drastically improve the quality of the water dedicated to human needs. Due to their intensive pollution by industrial wastes and by drainage waters from irrigated fields, the Syr Darya and Amu Darya rivers can no longer be considered as a source of safe and sustainable water supply. In such a situation, a number of scientists consider that the population's water supply must be achieved through a more comprehensive use of fresh and even subsaline groundwater resources from the coastal aquifers. The 2004 tsunami in the Indian Ocean caused imbalance in groundwater-surface water interactions and a disaster affecting thousands of kilometers of coastal zone in SE Asia. Many coastal wetlands were affected in the short term by the large inflow of salt seawater and littoral sediment deposited during the tsunami, and in the longer-term by changes in their hydrogeology caused by changes to coastlines and damage to sea-defenses. Many water quality and associated problems were generated by the tsunami. The tsunami has created imbalance in groundwater-surface water interactions and an accelerating process of salt-water intrusion and fresh-water contaminations in affected regions that now require drastic remediation measures.
Annual Site Environmental Report: 2008 (ASER)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sabba, D.
2009-11-09
This report provides information about environmental programs during the calendar year of 2008 at the SLAC National Accelerator Laboratory (SLAC), Menlo Park, California. Activities that span the calendar year, i.e., stormwater monitoring covering the winter season of 2008/2009 (October 2008 through May 2009), are also included. Production of an annual site environmental report (ASER) is a requirement established by the United States Department of Energy (DOE) for all management and operating (M&O) contractors throughout the DOE complex. SLAC is a federally-funded research and development center with Stanford University as the M&O contractor. Under Executive Order (EO) 13423, Strengthening Federal Environmental,more » Energy, and Transportation Management, and DOE Order 450.1A, Environmental Protection Program, SLAC effectively implements and integrates the key elements of an Environmental Management System (EMS) to achieve the site's integrated safety and environmental management system goals. For normal daily activities, SLAC managers and supervisors are responsible for ensuring that policies and procedures are understood and followed so that: (1) Worker safety and health are protected; (2) The environment is protected; and (3) Compliance is ensured. Throughout 2008, SLAC continued to improve its management systems. These systems provided a structured framework for SLAC to implement 'greening of the government' initiatives such as EO 13423 and DOE Orders 450.1A and 430.2B. Overall, management systems at SLAC are effective, supporting compliance with all relevant statutory and regulatory requirements. SLAC continues to demonstrate significant progress in implementing and integrating EMS into day-to-day operations and construction activities at SLAC. The annual management review and ranking of environmental aspects were completed this year by SLAC's EMS Steering Committee, the Environmental Safety Committee (ESC), and twelve objectives and targets were established for 2008. For each objective and target, a work plan, or Environmental Management Program (EMP) was completed and progress reports were routinely provided to SLAC senior management and the DOE SLAC Site Office (SSO). During 2008, there were no reportable releases to the environment from SLAC operations. In addition, many improvements in waste minimization, recycling, stormwater management, groundwater restoration, and SLAC's chemical management system (CMS) were continued during the year. The following are amongst SLAC's environmental accomplishments for 2008: a composting program at SLAC's onsite cafeteria was initiated, greater than 800 cubic feet of legacy radioactive waste were packaged and shipped from SLAC, a chemical redistribution program was developed, SLAC reduced the number of General Services Administration leased vehicles from 221 to 164, recycling of municipal waste was increased by approximately 140 tons during 2008, and site-wide releases of sulfur hexafluoride were reduced by 50 percent. In 2008, no radiological incidents occurred that increased radiation levels or released radioactivity to the environment. In addition to managing its radioactive wastes safely and responsibly, SLAC worked to reduce the amount of waste generated. SLAC has implemented programs and systems to ensure compliance with all radiological requirements related to the environment. Specifically, the Radiation Protection Radiological Waste Management Group developed a training course to certify Radioactive Waste Generators, conducted a training pilot, and developed a list of potential radioactive waste generators to train. Twenty eight generators were trained in 2008. As a best management practice, SLAC also reduced its tritium inventory by at least 95 percent by draining one of its accelerator cooling water systems; with the cooperation of the South Bayside System Authority, the West Bay Sanitary District and the DOE, SLAC discharged the cooling water to the sanitary sewer according to federal regulations and replenished the system with clean water. In 2008, the SLAC Environmental Restoration Program personnel continued work on site characterization and evaluation of remedial alternatives at four sites with volatile organic compounds in groundwater and several areas with polychlorinated biphenyls and low concentrations of lead in soil. SLAC is regulated under a site cleanup requirements order (board order) issued by the California Regional Water Quality Control Board (RWQCB), San Francisco Bay Region in May 2005 for the investigation and remediation of impacted soil and groundwater at SLAC. The board order lists specific tasks and deadlines for completion of groundwater and soil characterization and other remediation activities. All 2008 submittals to the RWQCB were completed and submitted on time.« less
A centrifuge CO2 pellet cleaning system
NASA Technical Reports Server (NTRS)
Foster, C. A.; Fisher, P. W.; Nelson, W. D.; Schechter, D. E.
1995-01-01
An advanced turbine/CO2 pellet accelerator is being evaluated as a depaint technology at Oak Ridge National Laboratory (ORNL). The program, sponsored by Warner Robins Air Logistics Center (ALC), Robins Air Force Base, Georgia, has developed a robot-compatible apparatus that efficiently accelerates pellets of dry ice with a high-speed rotating wheel. In comparison to the more conventional compressed air 'sandblast' pellet accelerators, the turbine system can achieve higher pellet speeds, has precise speed control, and is more than ten times as efficient. A preliminary study of the apparatus as a depaint technology has been undertaken. Depaint rates of military epoxy/urethane paint systems on 2024 and 7075 aluminum panels as a function of pellet speed and throughput have been measured. In addition, methods of enhancing the strip rate by combining infra-red heat lamps with pellet blasting and by combining the use of environmentally benign solvents with the pellet blasting have also been studied. The design and operation of the apparatus will be discussed along with data obtained from the depaint studies.
LATTICES FOR HIGH-POWER PROTON BEAM ACCELERATION AND SECONDARY BEAM COLLECTION AND COOLING.
DOE Office of Scientific and Technical Information (OSTI.GOV)
WANG, S.; WEI, J.; BROWN, K.
2006-06-23
Rapid cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: (a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics (b) long straight sections for low-loss injection, extraction, and high-efficiency collimation (c) dispersion-free straights to avoid longitudinal-transverse coupling, and (d) momentum cleaning at locations of large dispersion with missing dipoles.more » Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.« less
Clean air act and acid precipitation receiving increased attention
NASA Astrophysics Data System (ADS)
Burns, Douglas A.; Lawrence, Gregory B.; Murdoch, Peter S.
In 1990 the U.S. Congress passed Title IV of the Clean Air Act Amendments, which was intended to reduce the adverse effects of acid deposition by reducing emissions of the acid precursors,sulfur dioxide (SO2) and nitrogen oxides (Nox). Passage of Title IV was a response to the findings of a decade of research performed in large part through the National Acid Precipitation Assessment Program (NAPAP), which concluded that acid deposition posed a current and future threat to vulnerable forest and aquatic ecosystems [NAPAP, 1991].Now,with reauthorization of the 1990 Clean Air Act Amendments scheduled for 2000, Congress is considering several bills that would further reduce emissions to ensure the restoration of damaged ecosystems. Title IV requires a 10 million ton per year reduction in SO2 emissions below 1980 levels by 2010 and establishes a national cap of 8.95 million tons per year on utility emissions by 2010. Atmospheric sulfur deposition began to decline in the late 1970s as a result of energy conservation and provisions of the Clean Air Act of 1980. Since implementation of Phase I of Title IV in 1995, SO2 emissions have dropped from more than 20 million tons per year in the early 1990s to 18.3 million tons in 1995 [NAPAP, 1998].Consequently, reductions in atmospheric sulfur deposition have accelerated throughout the United States since 1995.
NASA Astrophysics Data System (ADS)
Caetano, Marco Antonio Leonel; Gherardi, Douglas Francisco Marcolino; Yoneyama, Takashi
2013-11-01
Socioeconomic-driven processes such as deforestation, forest degradation, forest fires, overgrazing, overharvesting of fuelwood and slash-and-burn practices constitute the primary sources of Greenhouse Gases (GHG) emissions in developing countries. Climate policies can induce the development of clean technology and offer incentives to accelerate reforestation. The Brazilian government has already acknowledged the urgency to invest in policies to reduce anthropogenic CO2 emissions in the Legal Brazilian Amazon (BA). In this work, we propose a scheme to estimate the required investments in clean technology and reforestation to achieve a prescribed short term target value for the atmospheric CO2 emission. Initially, a mathematical model is fitted to the available data to allow forecasting the values of the short term emissions of CO2 under a combination of investments in clean technology and reforestation. The investments to reduce the emissions of CO2 below a target value (400 million tons/year, starting at the initial value of 450) in 3 years’ time are proportional to the regional GDP. Using computer simulation it is possible to generate a range of possible investment values in clean technology and reforestation, so that the prescribed emission reduction is achieved without hindering economic growth. This strategy provides the necessary investment flexibility for the implementation of realistic climate policies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hazen, T.C.; Looney, B.B.; Fliermans, C.B.
1994-06-01
The US Department of Energy, Office of Technology Development, has been sponsoring full-scale environmental restoration technology demonstrations for the past 4 years. The Savannah River Site Integrated Demonstration focuses on ``Clean-up of Soils ad Groundwater Contaminated with Chlorinated VOCs.`` Several laboratories including our own had demonstrated the ability of methanotrophic bacteria to completely degrade or mineralize chlorinated solvents, and these bacteria were naturally found in soil and aquifer material. Thus the test consisted of injection of methane mixed with air into the contaminated aquifer via a horizontal well and extraction from the vadose zone via a parallel horizontal well.
Modelling reaction front formation and oscillatory behaviour in a contaminant plume
NASA Astrophysics Data System (ADS)
Cribbin, Laura; Fowler, Andrew; Mitchell, Sarah; Winstanley, Henry
2013-04-01
Groundwater contamination is a concern in all industrialised countries that suffer countless spills and leaks of various contaminants. Often, the contaminated groundwater forms a plume that, under the influences of regional groundwater flow, could eventually migrate to streams or wells. This can have catastrophic consequences for human health and local wildlife. The process known as bioremediation removes pollutants in the contaminated groundwater through bacterial reactions. Microorganisms can transform the contaminant into less harmful metabolic products. It is important to be able to predict whether such bioremediation will be sufficient for the safe clean-up of a plume before it reaches wells or lakes. Borehole data from a contaminant plume which resulted from spillage at a coal carbonisation plant in Mansfield, England is the motivation behind modelling the properties of a contaminant plume. In the upper part of the plume, oxygen is consumed and a nitrate spike forms. Deep inside the plume, nitrate is depleted and oscillations of organic carbon and ammonium concentration profiles are observed. While there are various numerical models that predict the evolution of a contaminant plume, we aim to create a simplified model that captures the fundamental characteristics of the plume while being comparable in accuracy to the detailed numerical models that currently exist. To model the transport of a contaminant, we consider the redox reactions that occur in groundwater systems. These reactions deplete the contaminant while creating zones of dominant terminal electron accepting processes throughout the plume. The contaminant is depleted by a series of terminal electron acceptors, the order of which is typically oxygen, nitrate, manganese, iron, sulphate and carbon dioxide. We describe a reaction front, characteristic of a redox zone, by means of rapid reaction and slow diffusion. This aids in describing the depletion of oxygen in the upper part of the plume. To describe the oscillatory behaviour of the reactant concentrations deeper in the plume, we employ the dynamics of competing bacterial populations. We show that the oscillatory behaviour, characteristic of competing populations, can describe the oscillations observed among the reactants.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Evans, Charles
The energy landscape has undergone profound transformation, with dramatic shifts having an impact on U.S. productivity, global investment, manufacturing operations, and job creation. The sense of urgency for a tighter linkage between clean technologies, energy and advanced manufacturing has only grown. Prior to 2009, the tone of the nation’s energy conversation was centered on how to deal with long-standing energy security challenges and scarcity. Today, the tone is focused on seizing emerging energy growth opportunities to transform America’s industrial base and job creation outlook—centering on energy abundance and strength. In this context, the Council on Competitiveness and the Department ofmore » Energy’s Office of Energy Efficiency & Renewable Energy (EERE) teamed in the American Energy & Manufacturing Competitiveness (AEMC) Partnership to tackle two major goals via a multi-year partnership. The AEMC Partnership identified means to: • Increase U.S. competitiveness in the production of clean energy products • Increase U.S. manufacturing competitiveness across the board by increasing energy productivity The AEMC Partnership has engaged hundreds of leaders from industry, academia, labor and government in a series of 9 regional, progressive dialogues; original research; and 4 national summits. The AEMC dialogues and summits spanned the United States—taking place in our nation’s greatest manufacturing, research, technology and innovation hotspots. The goals of the AEMC Partnership have been straightforward: • State and define key barriers, challenges, and problems in U.S. competitiveness in manufacturing of clean energy products, energy efficiency products, and advanced manufacturing products. • Dive deeply into these problems and generate policies, solutions, concepts and models where the U.S. public and private sectors can work together to solve these problems. • Catalyze policy solutions—including models for public-private partnership (PPP) pilots—to increase competitive manufacturing of clean energy and energy efficiency products in the USA. • Elevate and increase awareness of the importance and benefits of competitive clean energy manufacturing. • Understand how energy game-changers, like breakthrough technologies, impact U.S. clean energy and energy efficient manufacturing. The Council on Competitiveness worked with its stakeholder network to generate potential PPP concepts and proposals to advance the goals of the AEMC Partnership. Magnify outlines 2 PPP concepts—honed by dialogues, conversations, interviews and research—that could be carried out by EERE and/or the Council to increase the competitive production of clean energy products, energy efficient products, and advanced manufacturing in the USA. Magnify’s 2 PPP concepts aim to bridge very specific gaps in the nation’s innovation ecosystem: • Clean Energy Materials Accelerator: This PPP concept focuses on reducing the risks associated with deploying newly developed materials in commercial products and processes by creating a platform to identify and address common challenges; increasing access to existing materials qualification and characterization tools; and creating standards for advanced materials with leaders in industry, academic, government, and other organizations. Why accelerate materials production? As the AEMC Partnership Dialogue and supporting research from the public and private sectors have documented, countries that lead in making next-generation materials will gain significant competitive advantage by unleashing a new wave of manufacturing innovation. • Manufacturing and Energy Technology Accelerator: This PPP concept is a new, physical and virtual collaborative resource platform designed to connect the nation’s world-class innovation institutions—SMEs, large multinational companies, universities, national laboratories, etc.—to facilitate the transition of cutting-edge clean energy technologies into products, processes, or services that are manufactured in the United States. Why should public and private sector leaders in innovation partner to co-create a scale-up platform? The United States is already a mecca for the world’s greatest minds in science and technology—drawn to our shores by world-class universities and opportunities to work with global leaders in innovation. Unfortunately, when it comes time to bring their ideas to market, technologists and entrepreneurs often choose, or are forced, to locate manufacturing overseas. The United States must regain its position in the world as a national scale-up platform for next-generation technologies. A thorough explanation of these PPP concepts and the rationale behind these recommendations is provided in Part 3 of Magnify. Magnify is an important step on the critical journey to define barriers, challenges and problems in the manufacturing of clean energy products and energy efficient products—and further honing concepts for scalable, public-private partnerships—to increase the competitive manufacturing of clean energy and energy efficient products, and the energy productivity throughout the U.S. manufactur¬ing sector. The rest of the world is waking up to the opportunities associated with a strategic focus on manufacturing and energy competitiveness. Global competition is on the rise, and the stakes are high for the United States to act now, to act decisively, and to leverage inherent strengths to ensure a more prosperous, competitive future for decades to come.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Woloshun, Keith Albert; Dale, Gregory E.; Naranjo, Angela Carol
The NorthStar Medical Technologies 99Mo production facility configuration is envisioned to be 8 accelerator pairs irradiating 7 100Mo targets (one spare accelerator pair undergoing maintenance while the other 7 pairs are irradiating targets). The required shielding in every direction for the accelerators is initially estimated to be 10 feet of concrete. With the accelerator pairs on one (ground) level and spaced with the required shielding between adjacent pairs, the only practical path for target insertion and removal while minimizing floor space is vertical. The current scheme then requires a target vertical lift of nominally 10 feet through a shield stack.more » It is envisioned that the lift will be directly into a hot cell where an activated target can be removed from its holder and a new target attached and lowered. The hot cell is on a rail system so that a single hot cell can service all active target locations, as well as deliver the ready targets to the separations lab. On this rail system, coupled to the hot cell, will be a helium recovery and clean-up system. All helium coolant equipment is located on the upper level near to the target removal point.« less
Interaction of abiotic and microbial processes in hexachloroethane reduction in groundwater
Roberts, A. Lynn; Gschwend, Philip M.
1994-01-01
In order to gain insight into mechanisms of hexachloroethane reduction, hexa- and pentachloroethane transformation rates were measured in anaerobic groundwater samples. For samples spiked with pentachloroethane, disappearance of pentachloroethane was accompanied by tetrachloroethylene production. Transformation rates were similar in unpoisoned and in HgCl2-poisoned samples, and rates were within ±20% of predictions based on measured pH and second-order dehydrochlorination rate constants determined in clean laboratory systems, indicating that the fate of pentachloroethane in this system is dominated by abiotic reactions. No hexachloroethane transformation was observed in HgCl2-poisoned samples, whereas in unpoisoned samples, hexachloroethane disappearance was accompanied by production of tetrachloroethylene as well as traces of pentachloroethane. Although only minor amounts of pentachloroethane accumulated, as much as 30% of the hexachloroethane transformation pathway proceeds via a pentachloroethane intermediate. This suggests that the microbial reduction of hexachloroethane proceeds at least in part through a free-radical mechanism. To the extent that hexachloroethane reduction to tetrachloroethylene occurs through a pentachloroethane intermediate, the first step in the sequence, the microbially-mediated step, is the slow step; the subsequent abiotic dehydrohalogenation step occurs much more rapidly.
Lara, Paloma; Morett, Enrique; Juárez, Katy
2017-11-01
Stimulation of microbial reduction of Cr(VI) to the less toxic and less soluble Cr(III) through electron donor addition has been regarded as a promising approach for the remediation of chromium-contaminated soil and groundwater sites. However, each site presents different challenges; local physicochemical characteristics and indigenous microbial communities influence the effectiveness of the biostimulation processes. Here, we show microcosm assays stimulation of microbial reduction of Cr(VI) in highly alkaline and saline soil samples from a long-term contaminated site in Guanajuato, Mexico. Acetate was effective promoting anaerobic microbial reduction of 15 mM of Cr(VI) in 25 days accompanied by an increase in pH from 9 to 10. Our analyses showed the presence of Halomonas, Herbaspirillum, Nesterenkonia/Arthrobacter, and Bacillus species in the soil sample collected. Moreover, from biostimulated soil samples, it was possible to isolate Halomonas spp. strains able to grow at 32 mM of Cr(VI). Additionally, we found that polluted groundwater has bacterial species different to those found in soil samples with the ability to resist and reduce chromate using acetate and yeast extract as electron donors.
Biocolloid transport in water saturated columns packed with sand
NASA Astrophysics Data System (ADS)
Syngouna, V. I.; Chrysikopoulos, C.
2010-12-01
Protection of groundwater supplies from microbial contamination necessitates a solid understanding of the factors controlling the migration and retention of pathogenic organisms (biocolloids) in the subsurface. The transport behavior of three waterborne pathogens (Escherichia coli, MS2, and ΦΧ174) was investigated using laboratory-scale columns packed with clean quartz sand. Various grain sizes and pore water velocities were examined. Though coliform bacteria and coliphages are used worldwide to indicate fecal pollution of groundwater, the various parameters controlling the transport of Escherichia coli MS2 and ΦΧ174 in the subsurface are not fully understood. In this study, the attachment behavior of Escherichia coli, MS2, and ΦΧ174 onto ultra-pure quartz sand were evaluated. The mass recoveries of the three biocolloids examined were found to be proportional to the sand size. The observed mass recoveries were in the order: Escherichia coli > ΦΧ174 > MS2. To assess the importance of biocolloid attachment, the single collector removal efficiency, and the collision efficiency were quantified using the classical colloid filtration theory. Our results indicate that the secondary energy minimum plays an important role in biocolloid deposition even for smaller biocolloid particles (e.g. viruses).
Assessment of groundwater quality in a typical rural settlement in southwest Nigeria.
Adekunle, I M; Adetunji, M T; Gbadebo, A M; Banjoko, O P
2007-12-01
In most rural settlements in Nigeria, access to clean and potable water is a great challenge, resulting in water borne diseases. The aim of this study was to assess the levels of some physical, chemical, biochemical and microbial water quality parameters in twelve hand - dug wells in a typical rural area (Igbora) of southwest region of the country. Seasonal variations and proximity to pollution sources (municipal waste dumps and defecation sites) were also examined. Parameters were determined using standard procedures. All parameters were detected up to 200 m from pollution source and most of them increased in concentration during the rainy season over the dry periods, pointing to infiltrations from storm water. Coliform population, Pb, NO3- and Cd in most cases, exceeded the World Health Organization recommended thresholds for potable water. Effect of distance from pollution sources was more pronounced on fecal and total coliform counts, which decreased with increasing distance from waste dumps. The qualities of the well water samples were therefore not suitable for human consumption without adequate treatment. Regular monitoring of groundwater quality, abolishment of unhealthy waste disposal practices and introduction of modern techniques are recommended.
1999-04-06
On the site of Launch Complex 34, key participants sign a Memorandum of Agreement, formalizing cooperative efforts of NASA, the U.S. Air Force, and federal agencies in ground-water cleanup initiatives. Seated at the table, from left to right, are Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; Roy Bridges Jr., director of John F. Kennedy Space Center; Walter Kovalick Jr., Ph.D., director, Technology Innovation Office, U.S. Environmental Protection Agency. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally
Kazakhstan In situ BioTransformation of Mercury ...
Our final international work on the biological decontamination of the mercury contamination of soils in the Northern outskirts of Pavlodar as a result of activity at the former PO “Khimprom” chemical plant is reported here. The plant produced chlorine and alkali from the 1970s into the 1990s using the electrolytic amalgam method entailing the use of massive amounts of mercury. Ground water became contaminated with Hg resulting in a plume 470 m wide, 1.9 km long, estimated to contain 2 million cubic meters of water. This plume could reach the River Irtysh, a source of drinking water for large cities in Kazakhstan and Russia. Significant amounts of mercuric compounds are deposited in the sediments of Lake Balkyldak, 1.5 km north of the factory. This lake occasionally received wastewater from the factory. Phase I of the PO “Kimprom” clean-up that isolated the major sources of mercury at the site was completed in 2004. However, significant amounts of mercury remain underground including groundwater contaminated with Hg in the form of HgCl2 with little to no elemental or methyl mercury (MeHg). Develop biotechnology strategies to mitigate mercury contamination in groundwater
NASA Astrophysics Data System (ADS)
Hurwitz, Shaul; Goff, Fraser; Janik, Cathy J.; Evans, William C.; Counce, Dale A.; Sorey, Michael L.; Ingebritsen, Steven E.
2003-01-01
We interpret new chemical and isotopic data from samples collected between October 1998 and March 2002 from the NSF well (also called the Keller well), the only deep well on the summit of Kilauea Volcano, Hawaii. Sample collection followed cleaning of the well, which renewed access to the hydrothermal system very close to the loci of magmatic and fumarolic activity. The chemical and isotopic compositions of the new samples differ remarkably from data published previously. On the basis of the S/Cl ratio and carbon and helium isotopes we conclude that the thermal fluids formed by condensation of magmatic gas into shallow meteoric groundwater. Gas condensation was followed by a complex pattern of basalt dissolution accompanied by an increase of fluid pH and precipitation of secondary minerals. Geochemical modeling and geothermometry imply that the fluids equilibrated with an assemblage of secondary minerals at temperatures between 90 and 140°C. The significantly different chemical composition of the NSF well fluids from that of springs along the southern coast of the island indicates that mass transport from the summit region toward the lower flanks of the volcano is limited.
Bea, Sergio A; Wainwright, Haruko; Spycher, Nicolas; Faybishenko, Boris; Hubbard, Susan S; Denham, Miles E
2013-08-01
Acidic low-level waste radioactive waste solutions were discharged to three unlined seepage basins at the F-Area of the Department of Energy (DOE) Savannah River Site (SRS), South Carolina, USA, from 1955 through 1989. Despite many years of active remediation, the groundwater remains acidic and contaminated with significant levels of U(VI) and other radionuclides. Monitored Natural Attenuation (MNA) is a desired closure strategy for the site, based on the premise that regional flow of clean background groundwater will eventually neutralize the groundwater acidity, immobilizing U(VI) through adsorption. An in situ treatment system is currently in place to accelerate this in the downgradient portion of the plume and similar measures could be taken upgradient if necessary. Understanding the long-term pH and U(VI) adsorption behavior at the site is critical to assess feasibility of MNA along with the in-situ remediation treatments. This paper presents a reactive transport (RT) model and uncertainty quantification (UQ) analyses to explore key controls on the U(VI)-plume evolution and long-term mobility at this site. Two-dimensional numerical RT simulations are run including the saturated and unsaturated (vadose) zones, U(VI) and H(+) adsorption (surface complexation) onto sediments, dissolution and precipitation of Al and Fe minerals, and key hydrodynamic processes are considered. UQ techniques are applied using a new open-source tool that is part of the developing ASCEM reactive transport modeling and analysis framework to: (1) identify the complex physical and geochemical processes that control the U(VI) plume migration in the pH range where the plume is highly mobile, (2) evaluate those physical and geochemical parameters that are most controlling, and (3) predict the future plume evolution constrained by historical, chemical and hydrological data. The RT simulation results show a good agreement with the observed historical pH and concentrations of U(VI), nitrates and Al concentrations at multiple locations. Mineral dissolution and precipitation combined with adsorption reactions on goethite and kaolinite (the main minerals present with quartz) could buffer pH at the site for long periods of time. UQ analysis using the Morris one-at-a-time (OAT) method indicates that the model/parameter is most sensitive to the pH of the waste solution, discharge rates, and the reactive surface area available for adsorption. However, as a key finding, UQ analysis also indicates that this model (and parameters) sensitivity evolves in space and time, and its understanding could be crucial to assess the temporal efficiency of a remediation strategy in contaminated sites. Results also indicate that residual U(VI) and H(+) adsorbed in the vadose zone, as well as aquifer permeability, could have a significant impact on the acidic plume long-term mobility. Copyright © 2013 Elsevier B.V. All rights reserved.
Plasmaless cleaning process of silicon surface using chlorine trifluoride
NASA Astrophysics Data System (ADS)
Saito, Yoji; Yamaoka, Osamu; Yoshida, Akira
1990-03-01
Plasmaless etching using ClF3 gas around room temperature has been investigated for the silicon substrates with the various thicknesses of native oxide. The native oxide can be removed with ClF3 gas. A specular surface is obtained by ultraviolet light irradiation which remarkably accelerates the removal of the native oxide without changing the etch rate of silicon. The etched surface is analyzed with Auger electron measurement, indicating the existence of Cl atoms on it.
1983-07-01
the decomposition reaction (Leider, 1981; Kageyama, 1973; Wolfrom, 1956), 2) Hydrolysis of linkages between glucose units (Urbanski, 1964), 3... dehydration ), 2) Acceleration period (to 50 percent decomposition ), 3) First order reaction rate period. The products of thermal decomposition of...simple mechanism to clean an entire building at once. o Depending on the contaminant, thermal decomposition and or hydrolysis may occur. o May be
Monas, Andrea; Užarević, Krunoslav; Halasz, Ivan; Kulcsár, Marina Juribašić; Ćurić, Manda
2016-10-27
Room-temperature accelerated aging in the solid state has been applied for atom- and energy-efficient activation of either one or two C-H bonds of azobenzene and methyl orange by palladium(ii) acetate. Organopalladium complexes are prepared in quantitative reactions without potentially harmful side products. Dicyclopalladated methyl orange is water-soluble and is a selective chromogenic biothiol sensor at physiologically-relevant micromolar concentrations in buffered aqueous media.
Business logic for geoprocessing of distributed geodata
NASA Astrophysics Data System (ADS)
Kiehle, Christian
2006-12-01
This paper describes the development of a business-logic component for the geoprocessing of distributed geodata. The business logic acts as a mediator between the data and the user, therefore playing a central role in any spatial information system. The component is used in service-oriented architectures to foster the reuse of existing geodata inventories. Based on a geoscientific case study of groundwater vulnerability assessment and mapping, the demands for such architectures are identified with special regard to software engineering tasks. Methods are derived from the field of applied Geosciences (Hydrogeology), Geoinformatics, and Software Engineering. In addition to the development of a business logic component, a forthcoming Open Geospatial Consortium (OGC) specification is introduced: the OGC Web Processing Service (WPS) specification. A sample application is introduced to demonstrate the potential of WPS for future information systems. The sample application Geoservice Groundwater Vulnerability is described in detail to provide insight into the business logic component, and demonstrate how information can be generated out of distributed geodata. This has the potential to significantly accelerate the assessment and mapping of groundwater vulnerability. The presented concept is easily transferable to other geoscientific use cases dealing with distributed data inventories. Potential application fields include web-based geoinformation systems operating on distributed data (e.g. environmental planning systems, cadastral information systems, and others).
Liao, Peng; Al-Ani, Yasir; Malik Ismael, Zainab; Wu, Xiaohui
2015-01-01
A recently developed Pd-based electro-Fenton (E-Fenton) process enables efficient in situ remediation of organic contaminants in groundwater. In the process, H2O2, Fe(II), and acidic conditions (~pH 3) are produced in situ to facilitate the decontamination, but the role of ubiquitous natural organic matters (NOM) remain unclear. This study investigated the effect of Aldrich humic acid (HA) on the transformation of toluene by the Pd-based E-Fenton process. At pH 3 with 50 mA current, the presence of HA promoted the efficiency of toluene transformation, with pseudo-first-order rate constants increase from 0.01 to 0.016 as the HA concentration increases from 0 to 20 mg/L. The HA-enhanced toluene transformation was attributed to the accelerated thermal reduction of Fe(III) to Fe(II), which led to production of more hydroxyl radicals. The correlation of the rate constants of toluene transformation and HA decomposition validated hydroxyl radical (·OH) as the predominant reactive species for HA decomposition. The finding of this study highlighted that application of the novel Pd-based E-Fenton process in groundwater remediation may not be concerned by the fouling from humic substances. PMID:25783864
Liao, Peng; Al-Ani, Yasir; Malik Ismael, Zainab; Wu, Xiaohui
2015-03-18
A recently developed Pd-based electro-Fenton (E-Fenton) process enables efficient in situ remediation of organic contaminants in groundwater. In the process, H₂O₂, Fe(II), and acidic conditions (~pH 3) are produced in situ to facilitate the decontamination, but the role of ubiquitous natural organic matters (NOM) remain unclear. This study investigated the effect of Aldrich humic acid (HA) on the transformation of toluene by the Pd-based E-Fenton process. At pH 3 with 50 mA current, the presence of HA promoted the efficiency of toluene transformation, with pseudo-first-order rate constants increase from 0.01 to 0.016 as the HA concentration increases from 0 to 20 mg/L. The HA-enhanced toluene transformation was attributed to the accelerated thermal reduction of Fe(III) to Fe(II), which led to production of more hydroxyl radicals. The correlation of the rate constants of toluene transformation and HA decomposition validated hydroxyl radical (·OH) as the predominant reactive species for HA decomposition. The finding of this study highlighted that application of the novel Pd-based E-Fenton process in groundwater remediation may not be concerned by the fouling from humic substances.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2008-08-09
The MIT Clean Energy Prize was established to accelerate the pace of innovation in the energy space, specifically with regard to clean energy and to reduce our dependence on foreign oil. Through a prize structure designed to incent new ideas to be brought forward coupled with a supporting infrastructure to educate, mentor, network and provide a platform for visibility, it was believed we could achieve this goal in a very efficient and effective manner. The grand prize of $200K was meant to be the highly visible and attractive carrot to achieve this and through a public-private partnership of sponsors whomore » held a long term view (i.e., they were not Venture Capitalists or law firms looking for short term business through advantaged deal flow). It was also designed to achieve this in a highly inclusive manner. Towards this end, while MIT was the platform on which the competition was run, and this brought some instant cache and differentiation, the competition was open to all teams which had at least one US citizen. Both professional teams and student teams were eligible.« less
CONTINUOUS ABORT GAP CLEANING AT RHIC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
DREES,A.FLILLER,R.III.FU,W.MICHNOFF,R.
2004-07-05
Since the RHIC Au-Au run in the year 2001 the 200 MHz cavity system was used at storage and a 28 MHz system during injection and acceleration. The rebucketing procedure potentially causes a higher debunching rate of heavy ion beams in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam can easily account for more than 50% of the total beam intensity. This effect is even stronger with the achieved high intensities of the RHIC Au-Au run in 2004. A beam abort at the presence of a lot of debunched beammore » bears the risk of magnet quenching and experimental detector damage due to uncontrolled beam losses. Thus it is desirable to avoid any accumulation of debunched beam from the beginning of each store, in particular to anticipate cases of unscheduled beam aborts due to a system failure. A combination of a fast transverse kickers and the new 2-stage copper collimator system are used to clean the abort gap continuously throughout the store with a repetition rate of 1 Hz. This report gives. an overview of the new gap cleaning procedure and the achieved performance.« less
NASA Astrophysics Data System (ADS)
Kujinga, Krasposy; Vanderpost, Cornelis; Mmopelwa, Gagoitseope; Wolski, Piotr
Globally, water security is negatively affected by factors that include climatic and hydrological conditions, population growth, rural-urban migration, increased per-capita water use, pollution and over-abstraction of groundwater. While Botswana has made strides in providing safe and clean water to its population since independence in 1966, over the years, a combination of factors have contributed to water security problems in different settlement categories of the country (i.e., primary, secondary, tertiary and ungazetted settlements) in general and in the district of Ngamiland in particular. To study water security problems differentiated by settlement category, this study employed quantitative data collection methods (i.e. household structured questionnaires) and qualitative data collection methods (i.e. key informant interviews, observation, focus group discussions and informal interviews), complemented by a review of relevant literature. Water security in all settlements is affected by status of the settlement, i.e. gazetted or ungazetted, climatic and hydrological factors and water governance challenges. In large villages such as Maun, factors threatening water security include population growth, urbanization, management challenges, old water supply and distribution infrastructure, increased demand for individual connections and changing lifestyles. Small gazetted and ungazetted settlements encounter problems related to limited sources of water supply as well as salinity of groundwater resources. In order to enhance water security in different settlement categories, Botswana has to develop a comprehensive water resources management strategy underpinned by integrated water resources management principles aimed at addressing factors contributing to water security problems. The strategy has to be settlement category specific. Large villages have to address factors related to demographic changes, urbanization, management challenges, water supply infrastructure and the introducing of water demand management activities. Households in small villages need provision of water from more sustainable sources while ungazetted settlements need better access to clean water.
Phillips, P J; Schubert, C; Argue, D; Fisher, I; Furlong, E T; Foreman, W; Gray, J; Chalmers, A
2015-04-15
Septic-system discharges can be an important source of micropollutants (including pharmaceuticals and endocrine active compounds) to adjacent groundwater and surface water systems. Groundwater samples were collected from well networks tapping glacial till in New England (NE) and sandy surficial aquifer New York (NY) during one sampling round in 2011. The NE network assesses the effect of a single large septic system that receives discharge from an extended health care facility for the elderly. The NY network assesses the effect of many small septic systems used seasonally on a densely populated portion of Fire Island. The data collected from these two networks indicate that hydrogeologic and demographic factors affect micropollutant concentrations in these systems. The highest micropollutant concentrations from the NE network were present in samples collected from below the leach beds and in a well downgradient of the leach beds. Total concentrations for personal care/domestic use compounds, pharmaceutical compounds and plasticizer compounds generally ranged from 1 to over 20 μg/L in the NE network samples. High tris(2-butoxyethyl phosphate) plasticizer concentrations in wells beneath and downgradient of the leach beds (>20 μg/L) may reflect the presence of this compound in cleaning agents at the extended health-care facility. The highest micropollutant concentrations for the NY network were present in the shoreline wells and reflect groundwater that is most affected by septic system discharges. One of the shoreline wells had personal care/domestic use, pharmaceutical, and plasticizer concentrations ranging from 0.4 to 5.7 μg/L. Estradiol equivalency quotient concentrations were also highest in a shoreline well sample (3.1 ng/L). Most micropollutant concentrations increase with increasing specific conductance and total nitrogen concentrations for shoreline well samples. These findings suggest that septic systems serving institutional settings and densely populated areas in coastal settings may be locally important sources of micropollutants to adjacent aquifer and marine systems. Published by Elsevier B.V.
Intrinsic bioremediation of MTBE-contaminated groundwater at a petroleum-hydrocarbon spill site
NASA Astrophysics Data System (ADS)
Chen, K. F.; Kao, C. M.; Chen, T. Y.; Weng, C. H.; Tsai, C. T.
2006-06-01
An oil-refining plant site located in southern Taiwan has been identified as a petroleum-hydrocarbon [mainly methyl tert-butyl ether (MTBE) and benzene, toluene, ethylbenzene, and xylenes (BTEX)] spill site. In this study, groundwater samples collected from the site were analyzed to assess the occurrence of intrinsic MTBE biodegradation. Microcosm experiments were conducted to evaluate the feasibility of biodegrading MTBE by indigenous microorganisms under aerobic, cometabolic, iron reducing, and methanogenic conditions. Results from the field investigation and microbial enumeration indicate that the intrinsic biodegradation of MTBE and BTEX is occurring and causing the decrease in MTBE and BTEX concentrations. Microcosm results show that the indigenous microorganisms were able to biodegrade MTBE under aerobic conditions using MTBE as the sole primary substrate. The detected biodegradation byproduct, tri-butyl alcohol (TBA), can also be biodegraded by the indigenous microorganisms. In addition, microcosms with site groundwater as the medium solution show higher MTBE biodegradation rate. This indicates that the site groundwater might contain some trace minerals or organics, which could enhance the MTBE biodegradation. Results show that the addition of BTEX at low levels could also enhance the MTBE removal. No MTBE removal was detected in iron reducing and methanogenic microcosms. This might be due to the effects of low dissolved oxygen (approximately 0.3 mg/L) within the plume. The low iron reducers and methanogens (<1.8×103 cell/g of soil) observed in the aquifer also indicate that the iron reduction and methanogenesis are not the dominant biodegradation patterns in the contaminant plume. Results from the microcosm study reveal that preliminary laboratory study is required to determine the appropriate substrates and oxidation-reduction conditions to enhance the biodegradation of MTBE. Results suggest that in situ or on-site aerobic bioremediation using indigenous microorganisms would be a feasible technology to clean up this MTBE-contaminated site.
[Simulation on remediation of benzene contaminated groundwater by air sparging].
Fan, Yan-Ling; Jiang, Lin; Zhang, Dan; Zhong, Mao-Sheng; Jia, Xiao-Yang
2012-11-01
Air sparging (AS) is one of the in situ remedial technologies which are used in groundwater remediation for pollutions with volatile organic compounds (VOCs). At present, the field design of air sparging system was mainly based on experience due to the lack of field data. In order to obtain rational design parameters, the TMVOC module in the Petrasim software package, combined with field test results on a coking plant in Beijing, is used to optimize the design parameters and simulate the remediation process. The pilot test showed that the optimal injection rate was 23.2 m3 x h(-1), while the optimal radius of influence (ROI) was 5 m. The simulation results revealed that the pressure response simulated by the model matched well with the field test results, which indicated a good representation of the simulation. The optimization results indicated that the optimal injection location was at the bottom of the aquifer. Furthermore, simulated at the optimized injection location, the optimal injection rate was 20 m3 x h(-1), which was in accordance with the field test result. Besides, 3 m was the optimal ROI, less than the field test results, and the main reason was that field test reflected the flow behavior at the upper space of groundwater and unsaturated area, in which the width of flow increased rapidly, and became bigger than the actual one. With the above optimized operation parameters, in addition to the hydro-geological parameters measured on site, the model simulation result revealed that 90 days were needed to remediate the benzene from 371 000 microg x L(-1) to 1 microg x L(-1) for the site, and that the opeation model in which the injection wells were progressively turned off once the groundwater around them was "clean" was better than the one in which all the wells were kept operating throughout the remediation process.
Decision support system for drinking water management
NASA Astrophysics Data System (ADS)
Janža, M.
2012-04-01
The problems in drinking water management are complex and often solutions must be reached under strict time constrains. This is especially distinct in case of environmental accidents in the catchment areas of the wells that are used for drinking water supply. The beneficial tools that can help decision makers and make program of activities more efficient are decision support systems (DSS). In general they are defined as computer-based support systems that help decision makers utilize data and models to solve unstructured problems. The presented DSS was developed in the frame of INCOME project which is focused on the long-term stable and safe drinking water supply in Ljubljana. The two main water resources Ljubljana polje and Barje alluvial aquifers are characterized by a strong interconnection of surface and groundwater, high vulnerability, high velocities of groundwater flow and pollutant transport. In case of sudden pollution, reactions should be very fast to avoid serious impact to the water supply. In the area high pressures arising from urbanization, industry, traffic, agriculture and old environmental burdens. The aim of the developed DSS is to optimize the activities in cases of emergency water management and to optimize the administrative work regarding the activities that can improve groundwater quality status. The DSS is an interactive computer system that utilizes data base, hydrological modelling, and experts' and stakeholders' knowledge. It consists of three components, tackling the different abovementioned issues in water management. The first one utilizes the work on identification, cleaning up and restoration of illegal dumpsites that are a serious threat to the qualitative status of groundwater. The other two components utilize the predictive capability of the hydrological model and scenario analysis. The user interacts with the system by a graphical interface that guides the user step-by-step to the recommended remedial measures. Consequently, the acquisition of information to support the water management's decisions is simplified and faster, thus contributing to more efficient water management and a safer supply of drinking water.
NASA Astrophysics Data System (ADS)
Torres Torres, N. I.; Padilla, I. Y.; Rivera, V. L.
2016-12-01
Eogenetic kart aquifers are characterized by well-developed conduit networks within a rock matrix having significant primary porosity and permeability. These aquifers are highly productive and serve as important source of water for multiple uses. As a consequence, eogenetic karst regions are attractive for industrial, urban, and agricultural development that can serve as contaminations sources for the aquifers. It is hypothesized that the distribution of contaminants in these aquifers are influenced by combined characteristics of source and hydrogeological features. This research assesses the spatio-temporal distribution of chlorinated volatile organic compounds (CVOCs) in the eogenetic karst aquifers of northern Puerto Rico (NPR) and studies the correlation between hydrogeological and anthropogenic variables and groundwater contamination using Geographic Information System and statistical methods. CVOCs, which are used as dry cleaning and industrial solvents, degreasers and paint or spot removers, are among the most commonly found groundwater contaminants in the world. The NPR karst aquifers have been heavily impacted by land development and groundwater contamination, particularly CVOCs, with Trichloroethylene, Tetrachloroethylene, and Carbon Tetrachloride among the most detected contaminants. The analysis shows that 62% of the samples and 78% of the sites sampled have presence of one or more CVOC, and that their concentrations vary with time. Detection and concentrations of certain CVOCs are associated with some sources of known contamination. Significant presence of CVOCs is also found near developed and agricultural land uses. The shallow aquifer shows greater presence of CVOCs (66%) than the confined aquifer (16%), with most detections occurring in areas of low and medium sinkholes coverage and medium hydraulic conductivities. Multivariate statistical analysis indicates that, indeed, the distribution of CVOCs in the karsts aquifers of NPR is influenced by a combination of contaminant source and hydrogeological factors. These factors, which facilitate the entry of contaminants into the system, and promote their transport and storage, have resulted in extensive spatial and temporal contamination of eogenetic karst groundwater systems, such as those found in northern Puerto Rico.
NASA Astrophysics Data System (ADS)
Borella, M.; Guido, Z.; Borella, P.; Ketron, T.
2009-12-01
A proliferation of potable water systems utilizing groundwater is currently underway in the Lake Titicaca region of the Bolivian Altiplano. With the aid of national and international organizations, rural communities are developing groundwater sources because the region’s surface water is highly contaminated with waterborne pathogens—the primary factor contributing to high child mortality rates in developing nations. According to UNICEF, 86 percent of Bolivian families have access to “improved” water systems, which predominantly take the form of deep groundwater wells or contained natural springs. While the water systems have worked well to reduce pathogens in drinking water systems that cause illnesses such as dysentery, the water is rarely tested for heavy metal contamination, such as arsenic and lead. While bacteria analysis is essential, it is not the only component of healthy drinking water. Testing for heavy metals is especially important in the Bolivian Altiplano because abundant volcanic deposits and massive sulfide deposits suggest that in some areas it is likely that the water contains elevated concentrations of heavy metals. In this study, Terra Resource Development International, A California-based 502(c)3 nonprofit organization, partnered with Stanford University, the Technical University of Bolivia, and the Bolivian Geologic and Mining Survey to collect water samples in 36 rural community situated in four watersheds feeding into Lake Titicaca. Water was collected from shallow, hand dug wells, deep groundwater wells, springs, and small rivers in the Tiwanku, Laja, Batallas, Achacachi watersheds and were analyzed for inorganic contaminants. Samples were analyzed at Stanford’s Environmental Measurements Facility using the Inductively Coupled Plasma (ICP) Spectrometer for major ions and heavy metals. Results will help determine which, if any, community water systems are at risk of heavy metal contamination, where more comprehensive sampling is needed, and will inform Bolivian water managers of the potential need for heavy metal analysis.
Tang, Li; Iddya, Arpita; Zhu, Xiaobo; ...
2017-10-13
The desalination of inland brackish groundwater offers the opportunity to provide potable drinking water to residents and industrial cooling water to industries located in arid regions. Geothermal brines are used to generate electricity, but often contain high concentrations of dissolved salt. Here in this paper, we demonstrate how the residual heat left in spent geothermal brines can be used to drive a membrane distillation (MD) process and recover desalinated water. Porous polypropylene membranes were coated with a carbon nanotube (CNT)/poly(vinyl alcohol) layer, resulting in composite membranes having a binary structure that combines the hydrophobic properties critical for MD with themore » hydrophilic and conductive properties of the CNTs. We demonstrate that the addition of the CNT layer increases membrane flux due to enhanced heat transport from the bulk feed to the membrane surface, a result of CNT's high thermal transport properties. Furthermore, we show how hydroxide ion generation, driven by water electrolysis on the electrically conducting membrane surface, can be used to efficiently dissolve silicate scaling that developed during the process of desalinating the geothermal brine, negating the need for chemical cleaning.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tang, Li; Iddya, Arpita; Zhu, Xiaobo
The desalination of inland brackish groundwater offers the opportunity to provide potable drinking water to residents and industrial cooling water to industries located in arid regions. Geothermal brines are used to generate electricity, but often contain high concentrations of dissolved salt. Here in this paper, we demonstrate how the residual heat left in spent geothermal brines can be used to drive a membrane distillation (MD) process and recover desalinated water. Porous polypropylene membranes were coated with a carbon nanotube (CNT)/poly(vinyl alcohol) layer, resulting in composite membranes having a binary structure that combines the hydrophobic properties critical for MD with themore » hydrophilic and conductive properties of the CNTs. We demonstrate that the addition of the CNT layer increases membrane flux due to enhanced heat transport from the bulk feed to the membrane surface, a result of CNT's high thermal transport properties. Furthermore, we show how hydroxide ion generation, driven by water electrolysis on the electrically conducting membrane surface, can be used to efficiently dissolve silicate scaling that developed during the process of desalinating the geothermal brine, negating the need for chemical cleaning.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aspuru-Guzik, Alan
2016-11-04
Clean, affordable, and renewable energy sources are urgently needed to satisfy the 10s of terawatts (TW) energy need of human beings. Solar cells are one promising choice to replace traditional energy sources. Our broad efforts have expanded the knowledge of possible donor materials for organic photovoltaics, while increasing access of our results to the world through the Clean Energy Project database (www.molecularspace.org). Machine learning techniques, including Gaussian Processes have been used to calibrate frontier molecular orbital energies, and OPV bulk properties (open-circuit voltage, percent conversion efficiencies, and short-circuit current). This grant allowed us to delve into the solid-state properties ofmore » OPVs (charge-carrier dynamics). One particular example allowed us to predict charge-carrier dynamics and make predictions about future hydrogen-bonded materials.« less
Development of a tandem-electrostatic-quadrupole accelerator facility for BNCT.
Kreiner, A J; Thatar Vento, V; Levinas, P; Bergueiro, J; Di Paolo, H; Burlon, A A; Kesque, J M; Valda, A A; Debray, M E; Somacal, H R; Minsky, D M; Estrada, L; Hazarabedian, A; Johann, F; Suarez Sandin, J C; Castell, W; Davidson, J; Davidson, M; Giboudot, Y; Repetto, M; Obligado, M; Nery, J P; Huck, H; Igarzabal, M; Fernandez Salares, A
2009-07-01
In this work we describe the present status of an ongoing project to develop a tandem-electrostatic-quadrupole (TESQ) accelerator facility for accelerator-based (AB) BNCT at the Atomic Energy Commission of Argentina in Buenos Aires. The project final goal is a machine capable of delivering 30 mA of 2.4 MeV protons to be used in conjunction with a neutron production target based on the (7)Li(p,n)(7)Be reaction slightly beyond its resonance at 2.25 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the (7)Li(p,n)(7)Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. An electrostatic machine is the technologically simplest and cheapest solution for optimized AB-BNCT. The machine being designed and constructed is a folded TESQ with a high-voltage terminal at 1.2 MV intended to work in air. Such a machine is conceptually shown to be capable of transporting and accelerating a 30 mA proton beam to 2.4 MeV. The general geometric layout, its associated electrostatic fields, and the acceleration tube are simulated using a 3D finite element procedure. The design and construction of the ESQ modules is discussed and their electrostatic fields are investigated. Beam transport calculations through the accelerator are briefly mentioned. Likewise, work related to neutron production targets, strippers, beam shaping assembly and patient treatment room is briefly described.
Kerminen, Kaisa; Le Moël, Romain; Harju, Vilhelmiina; Kontro, Merja H
2018-03-15
Pesticides leaching from soil to surface and groundwater are a global threat for drinking water safety, as no cleaning methods occur for groundwater environment. We examined whether peat, compost-peat-sand (CPS) mixture, NH 4 NO 3 , NH 4 NO 3 with sodium citrate (Na-citrate), and the surfactant methyl-β-cyclodextrin additions enhance atrazine, simazine, hexazinone, dichlobenil, and the degradate 2,6-dichlorobenzamide (BAM) dissipations in sediment slurries under aerobic and anaerobic conditions, with sterilized controls. The vadose zone sediment cores were drilled from a depth of 11.3-14.6m in an herbicide-contaminated groundwater area. The peat and CPS enhanced chemical atrazine and simazine dissipation, and the peat enhanced chemical hexazinone dissipation, all oxygen-independently. Dichlobenil dissipated under all conditions, while BAM dissipation was fairly slow and half-lives could not be calculated. The chemical dissipation rates could be associated with the chemical structures and properties of the herbicides, and additive compositions, not with pH. Microbial atrazine degradation was only observed in the Pseudomonas sp. ADP amended slurries, although the sediment slurries were known to contain atrazine-degrading microorganisms. The bioavailability of atrazine in the water phase seemed to be limited, which could be due to complex formation with organic and inorganic colloids. Atrazine degradation by indigenous microbes could not be stimulated by the surfactant methyl-β-cyclodextrin, or by the additives NH 4 NO 3 and NH 4 NO 3 with Na-citrate, although the nitrogen additives increased microbial growth. Copyright © 2017 Elsevier B.V. All rights reserved.
HIGH LEVELS OF URANIUM IN GROUNDWATER OF ULAANBAATAR, MONGOLIA
Nriagu, Jerome; Nam, Dong-Ha; Ayanwola, Titilayo A.; Dinh, Hau; Erdenechimeg, Erdenebayar; Ochir, Chimedsuren; Bolormaa, Tsend-Ayush
2011-01-01
Water samples collected from 129 wells in seven of the nine sub-divisions of Ulaanbaatar were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using Clean Lab methods. The levels of many trace elements were found to be very low with the average concentrations (ranges in brackets) being 0.9 (<0.1-7.9) μg/L for As; 7.7 (0.12-177) μg/L for Mn; 0.2 (<0.05-1.9) μg/L for Co; 16 (<0.1-686) μg/L for Zn; 0.7 (<0.1-1.8) μg/L for Se; <0.1 (<0.02-0.69) μg/L for Cd; and 1.3 (<0.02-32) μg/L for Pb. The levels of uranium were surprisingly elevated (mean, 4.6 μg/L; range <0.01-57 μg/L, with the values for many samples exceeding the World Health Organization's guideline of 15 μg/L for uranium in drinking water. Local rocks and soils appear to be the natural source of the uranium. The levels of uranium in Ulaanbaatar's groundwater are in the range that has been associated with nephrotoxicity, high blood pressure, bone dysfunction and likely reproductive impairment in human populations. We consider the risk associated with drinking the groundwater with elevated levels of uranium in Ulaanbaatar to be a matter for some public health concern and conclude that the paucity of data on chronic effects of low level exposure is a risk factor for continuing the injury to many people in this city. PMID:22142646
Hydrologic conditions in the Florida Panther National Wildlife Refuge, 2006-2007
Reese, Ronald S.
2010-01-01
Much of the surface water that flows into the Florida Panther National Wildlife Refuge (FPNWR) probably exits southward through Fakahatchee Strand as it did prior to development, because culverts and bridges constructed along I-75 allow overland flow to continue southward within the strand. During the dry season and periods of low water levels, however, much of the flow is diverted westward by the I-75 Canal into Merritt Canal at the southwestern corner of the FPNWR. Substantial drainage of groundwater from the FPNWR into the I-75 Canal is indicated by (1) greater surface-water outflows than inflows in the FPNWR, (2) flows that increase to the west along the I-75 Canal, and (3) correlation of rapid groundwater-level declines at sites close to the I-75 Canal with rapid declines in canal surface-water levels due to operation of a control structure in the Merritt Canal. This drainage of groundwater probably occurs through permeable limestone exposed in the I-75 Canal bank below a cap rock layer. Compared to predevelopment conditions, the time currently required to drain ponded water in some areas of the refuge should be less because of accelerated groundwater discharge into the I-75 Canal caused by the lowering of water levels in the canal during the peak of the wet season extending into the early dry season. This drainage probably reduces the duration of the hydroperiod in these wetlands from the wet season into the dry season, possibly reducing or limiting the extent or vitality of wildlife and plant community habitats.
Liu, Haizhou; Bruton, Thomas A; Doyle, Fiona M; Sedlak, David L
2014-09-02
Persulfate (S2O8(2-)) is being used increasingly for in situ chemical oxidation (ISCO) of organic contaminants in groundwater, despite an incomplete understanding of the mechanism through which it is converted into reactive species. In particular, the decomposition of persulfate by naturally occurring mineral surfaces has not been studied in detail. To gain insight into the reaction rates and mechanism of persulfate decomposition in the subsurface, and to identify possible approaches for improving its efficacy, the decomposition of persulfate was investigated in the presence of pure metal oxides, clays, and representative aquifer solids collected from field sites in the presence and absence of benzene. Under conditions typical of groundwater, Fe(III)- and Mn(IV)-oxides catalytically converted persulfate into sulfate radical (SO4(•-)) and hydroxyl radical (HO(•)) over time scales of several weeks at rates that were 2-20 times faster than those observed in metal-free systems. Amorphous ferrihydrite was the most reactive iron mineral with respect to persulfate decomposition, with reaction rates proportional to solid mass and surface area. As a result of radical chain reactions, the rate of persulfate decomposition increased by as much as 100 times when benzene concentrations exceeded 0.1 mM. Due to its relatively slow rate of decomposition in the subsurface, it can be advantageous to inject persulfate into groundwater, allowing it to migrate to zones of low hydraulic conductivity where clays, metal oxides, and contaminants will accelerate its conversion into reactive oxidants.
2015-01-01
Persulfate (S2O82–) is being used increasingly for in situ chemical oxidation (ISCO) of organic contaminants in groundwater, despite an incomplete understanding of the mechanism through which it is converted into reactive species. In particular, the decomposition of persulfate by naturally occurring mineral surfaces has not been studied in detail. To gain insight into the reaction rates and mechanism of persulfate decomposition in the subsurface, and to identify possible approaches for improving its efficacy, the decomposition of persulfate was investigated in the presence of pure metal oxides, clays, and representative aquifer solids collected from field sites in the presence and absence of benzene. Under conditions typical of groundwater, Fe(III)- and Mn(IV)-oxides catalytically converted persulfate into sulfate radical (SO4•–) and hydroxyl radical (HO•) over time scales of several weeks at rates that were 2–20 times faster than those observed in metal-free systems. Amorphous ferrihydrite was the most reactive iron mineral with respect to persulfate decomposition, with reaction rates proportional to solid mass and surface area. As a result of radical chain reactions, the rate of persulfate decomposition increased by as much as 100 times when benzene concentrations exceeded 0.1 mM. Due to its relatively slow rate of decomposition in the subsurface, it can be advantageous to inject persulfate into groundwater, allowing it to migrate to zones of low hydraulic conductivity where clays, metal oxides, and contaminants will accelerate its conversion into reactive oxidants. PMID:25133603
Analysis of radiation environmental safety for China's Spallation Neutron Source (CSNS)
NASA Astrophysics Data System (ADS)
Wang, Qing-Bin; Wu, Qing-Biao; Ma, Zhong-Jian; Zhang, Qing-Jiang; Li, Nan; Wu, Jing-Min; Liu, Jian; Zhang, Gang
2010-07-01
The China Spallation Neutron Source (CSNS) is going to be located in Dalang Town, Dongguan City in the Guangdong Province. In this paper we report the results of the parameters related with environment safety based on experiential calculations and Monte Carlo simulations. The main project of the accelerator is an under ground construction. On top there is a 0.5 m concrete and 5.0 m soil covering for shielding, which can reduce the dose out of the tunnel's top down to 0.2 μSv/h. For the residents on the boundary of the CSNS, the dose produced by skyshine, which is caused by the penetrated radiation leaking from the top of the accelerator, is no more than 0.68 μSv/a. When CSNS is operating normally, the maximal annual effective dose due to the emission of gas from the tunnel is 2.40×10-3 mSv/a to the public adult, and 2.29×10-3 mSv/a to a child, both values are two orders of magnitude less than the limiting value for control and management. CSNS may give rise to an activation of the soil and groundwater in the nearest tunnels, where the main productions are 3H, 7Be, 22Na, 54Mn, etc. But the specific activity is less than the exempt specific activity in the national standard GB13376-92. So it is safe to say that the environmental impact caused by the activation of soil and groundwater is insignificant. To sum up, for CSNS, as a powerful neutron source device, driven by a high-energy high-current proton accelerator, a lot of potential factors affecting the environment exist. However, as long as effective shieldings for protection are adopted and strict rules are drafted, the environmental impact can be kept under control within the limits of the national standard.
Completing the CCT mission: The challenge of change
DOE Office of Scientific and Technical Information (OSTI.GOV)
Monk, J.R.
1997-12-31
In order to complete the clean coal technology mission it will be necessary to determine CCT`s role in the restructured electricity industry and develop a strategy to promote that role. First, one must understand where the industry is headed and how clean coal technology fits into that future. Then, one needs to develop a strategy for getting from here to there, from where CCT is today to where it must be in five, ten or twenty years to be a viable option for decision-makers. Coal makes sense for the United States for several important reasons, not the least of whichmore » is its abundance here. It also makes sense in terms of its economic impact on large areas of the nation. And if coal makes sense, especially economically, then clean coal technology makes even more sense because of its potential to capitalize on this abundant resource in an environmentally friendly manner. But after nearly thirty years of involvement in the political world at all levels from Washington, D.C. to Washington, Indiana, the author has learned the hard way that ``common sense`` does not always, or even often, carry the day in the policymaking process. He believes that the future of clean coal technology hinges on the ability in the next few months and years to mobilize all those who favor that technology to move forward in a cohesive and coordinated effort to affect the policymaking and political process and thereby promote and accelerate CCT development. If this can be done, then the nation will be well on the way to completing the clean coal technology mission and meeting the challenge of change.« less
Dynamics of Nutrients Transport in Onsite Wastewater Treatment Systems
NASA Astrophysics Data System (ADS)
Toor, G.; De, M.
2013-05-01
Domestic wastewater is abundant in nutrients¬ that originate from various activities in the households. In developed countries, wastewater is largely managed by (1) centralized treatment where wastewater from large population is collected, treated, and discharged and (2) onsite treatment where wastewater is collected from an individual house, treated, and dispersed onsite; this system is commonly known as septic system or onsite wastewater treatment system (OWTS) and consist of a septic tank (collects wastewater) and drain-field (disperses wastewater in soil). In areas with porous sandy soils, the transport of nutrients from drain-field to shallow groundwater is accelerated. To overcome this limitation, elevated disposal fields (commonly called mounds) on top of the natural soil are constructed to provide unsaturated conditions for wastewater treatment. Our objective was to study the dynamics of nitrogen (N) and phosphorus (P) transport in the vadose zone and groundwater in traditional and advanced OWTS. Soil water samples were collected from the vadose zone by using suction cup lysimeters and groundwater samples were collected by using piezometers. Collected samples (wastewater, soil-water, groundwater) were analyzed for various water quality parameters. The pH (4.39-4.78) and EC (0.28-0.34 dS/m) of groundwater was much lower than both wastewater and soil-water. In contrast to >50 mg/L of ammonium-N in wastewater, concentrations in all lysimeters (0.02-0.81 mg/L) and piezometers (0.01-0.82 mg/L) were <1 mg/L; suggesting that >99% disappeared (primarily nitrified) in the vadose zone (<1.05-m soil profile depth). In the vadose zone of advanced system, heterotrophic and autrotrophic denitrification reduced nitrate-N concentrations to <0.12 mg/L, compared with >20 mg/L in the vadose zones of traditional systems (drip dispersal and gravel trench). Concentrations of chloride showed a distinct pattern of nitrate-N breakthrough in vadose zone and groundwater; the groundwater nitrate-N was elevated upto 19.2 mg/L after wastewater delivery in tradional systems. Total P in the wastewater was ~10 mg/L, but low in all lysimeters (0.046-1.72 mg/L) and piezometers (0.01-0.78 mg/L) indicating enhanced P attenuation in the vadose zone of all systems.
Submarine ground-water discharge: nutrient loading and nitrogen transformations
Kroeger, Kevin D.; Swarzenski, Peter W.; Crusius, John; Bratton, John F.; Charette, Matthew A.
2006-01-01
Eutrophication of coastal waters due to nonpoint source land-derived nitrogen (N) loads is a worldwide phenomenon and perhaps the greatest agent of change altering coastal ecology (National Research Council, 2000; Howarth and others, 2000). Within the United States, a majority of estuaries have been determined to be moderately to severely impaired by eutrophication associated with increasing nutrient loads (Bricker and others, 1999).In coastal watersheds with soils of high hydraulic conductivity and permeable coastal sediments, ground water is a major route of transport of freshwater and its solutes from land to sea. Freshwater flowing downgradient from aquifers may either discharge from a seepage face near the intertidal zone, or flow directly into the sea as submarine ground-water discharge (SGD) (fig. 1). In the coastal aquifer, entrainment of saline pore water occurs prior to discharge, producing a gradient in ground-water salinity from land to sea, referred to as a subterranean estuary (Moore, 1999). In addition, processes including density-driven flow and tidal pumping create brackish and saline ground-water circulation. Hence, submarine ground-water discharge often consists of a substantial amount of recirculating seawater. Mixing of fresh and saline ground waters in the context of coastal sediments may alter the chemical composition of the discharging fluid. Depending on the biogeochemical setting, removal of fixed N due to processes leading to N2 (dinitrogen gas) production in the nearshore aquifer and subterranean estuary may significantly attenuate land-derived N loads; or, processes such as ion exchange and tidal pumping in the subterranean estuary may substantially accelerate the transport of both land-derived and sediment re-mineralized N to estuarine water columns.As emphasized by Burnett and others (2001, 2002), a fundamental problem in evaluating the importance of ground-water discharge in marine geochemical budgets is the difficulty of collecting samples across the salinity gradients of coastal aquifers. In addition, locating and quantifying rates of submarine ground-water discharge remains a challenge due to the diffuse and spatially and temporally heterogeneous nature of discharge. As a result, with regard to the study of biogeochemical cycles and chemical loads to coastal waters, the seepage face and subterranean estuary are relatively new and under-studied zones in the aquatic cascade from watershed to sea. Processes occurring in those zones must be understood and considered for proper modeling and management of coastal water resources.
DOE Office of Scientific and Technical Information (OSTI.GOV)
2017-05-09
The 21st Century Power Partnership (21CPP) aims to accelerate the global transformation of power systems. The Power Partnership is a multilateral effort of the Clean Energy Ministerial (CEM) and serves as a platform for public-private collaboration to advance integrated policy, regulatory, financial, and technical solutions for the large-scale deployment of renewable energy in combination with deep energy efficiency and smart grid solutions. This fact sheet details the 21CPP's work in India.
NASA Helps Build Colorado Economy
2010-12-13
Representative from U.S. Senator Udall's office Jimmy Haugue reads remarks from U.S. Senator Udall at the Colorado State Capitol in Denver on Monday, Dec. 13, 2010, prior to the signing of an agreement with NASA that creates a Technology Acceleration Program and Regional Innovation Cluster for Aerospace and Clean Energy. A manufacturing park focused on rapid new product development and production will be developed to assist growing Colorado businesses while promoting the commercialization of technology developed for the space program. Photo Credit: (NASA/Bill Ingalls)
NASA Helps Build Colorado Economy
2010-12-13
Colorado Association for Manufacturing and Technology (CAMT) CEO Elaine Thorndike delivers remarks at the Colorado State Capitol in Denver on Monday, Dec. 13, 2010, prior to the signing of an agreement with NASA that creates a Technology Acceleration Program and Regional Innovation Cluster for Aerospace and Clean Energy. A manufacturing park focused on rapid new product development and production will be developed to assist growing Colorado businesses while promoting the commercialization of technology developed for the space program. Photo Credit: (NASA/Bill Ingalls)
1992-01-09
opportunity to spend eight weeks during the summer doing scientific research at the laboratory. Each student is assigned a mentor from the laboratory. During ...AAMRL) 1 A Study on Human Response to Dynamic Impact During Flight Caroline Ch,ag 2 Implementation of the Clean Air Act Relative to Toxicological Research...Crew Rest Intervals for Accelerated MAC Missions: Lessons Lori Olenick from Desert Storm 24 Air Crew Diets During Desert Storm Carol Salinas 25
Contrast Enhancement of the LOASIS CPA Laser and Effects on Electron Beam Performance of LWFA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Toth, Csaba; Gonsalves, Anthony J.; Panasenko, Dmitriy
2009-01-22
A nonlinear optical pulse cleaning technique based on cross-polarized wave (XPW) generation filtering [1] has been implemented to improve laser pulse contrast, and consequently to control pre-ionization in laser-plasma accelerator experiments. Three orders of magnitude improvement in pre-pulse contrast has been achieved, resulting in 4-fold increase in electron charge and improved stability of both the electron beam energy and THz radiation generated as a secondary process in the gas-jet-based LWFA experiments.
Geothermal Technologies Office FY 2017 Budget At-A-Glance
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2016-03-01
The Geothermal Technologies Office (GTO) accelerates deployment of clean, domestic geothermal energy by supporting innovative technologies that reduce the cost and risks of development. This abundant resource generates energy around the clock and has the potential to supply more than 100 GWe of electricity—roughly one-tenth of America’s energy demand. By optimizing the value stream for electricity production and cascaded uses, the office aims to make geothermal energy a fully cost-competitive, widely available, and geographically diverse component of the national energy mix.
Oceanographic Effects on Maritime Threats: Mines and Oil Spills in the Strait of Hormuz
2007-03-01
could potentially be used (Kreil, 2004). The full flow potential for all the pipelines together is about seven million barrels of oil a day... potential oil spills, and drift mining could mean the difference for a faster recovery from an incident at this choke point. The faster the clean...θ is potential temperature, g is the acceleration due to gravity, 1Λ is the dissipation length scale, , , and wu v′ ′ ′ denote the components
NASA Helps Build Colorado Economy
2010-12-13
NIST MEP Director Roger Kilmer delivers remarks at the Colorado State Capitol in Denver on Monday, Dec. 13, 2010, prior to the signing of an agreement between the Colorado Association for Manufacturing and Technology (CAMT) and NASA that creates a Technology Acceleration Program and Regional Innovation Cluster for Aerospace and Clean Energy. A manufacturing park focused on rapid new product development and production will be developed to assist growing Colorado businesses while promoting the commercialization of technology developed for the space program. Photo Credit: (NASA/Bill Ingalls)
DOE Office of Scientific and Technical Information (OSTI.GOV)
None, None
Established in 2012, the 21CPP South Africa Programme is a global initiative that connects South African stakeholders with an international communityof expertise. The overall goal of this program is to support South Africa's power system transformation by accelerating the transition to a reliable, financially robust, and low-carbon power system. 21CPP activities focus on achieving positive outcomes for all participants, especially addressing critical questions and challenges facing system planners, regulators, and operators.
Low-pressure RF remote plasma cleaning of carbon-contaminated B4C-coated optics
NASA Astrophysics Data System (ADS)
Moreno Fernández, H.; Thomasset, M.; Sauthier, G.; Rogler, D.; Dietsch, R.; Barrett, R.; Carlino, V.; Pellegrin, E.
2017-05-01
Boron carbide (B4C) - due to its exceptional mechanical properties - is one of the few existing materials that can withstand the extremely high brilliance of the photon beam from free electron lasers (FELs) and is thus of considerable interest for optical applications in this field. However, as in the case of many other optics operated at modern accelerator-, plasma-, or laser-based light source facilities, B4C-coated optics are subject to ubiquitous carbon contaminations. These contaminations - that are presumably produced via cracking of CHx and CO2 molecules by photoelectrons emitted from the optical components - represent a serious issue for the operation of the pertinent high performance beamlines due to a severe reduction of photon flux and beam coherence, not necessarily restricted to the photon energy range of the carbon K-edge. Thus, a variety of B4C cleaning technologies have been developed at different laboratories with varying success [1]. Here, we present a study regarding the low-pressure RF plasma cleaning of a series of carbon-contaminated B4C test samples via an inductively coupled O2/Ar and Ar/H2 remote RF plasma produced using the IBSS GV10x plasma source following previous studies using the same RF plasma source [2, 3]. Results regarding the chemistry, morphology as well as other aspects of the B4C optical coatings and surfaces before and after the plasma cleaning process are reported.
NASA Astrophysics Data System (ADS)
Ledley, T. S.; Niepold, F., III; Bozuwa, J.; Davis, A.; Fraser, J.; Kretser, J.; Poppleton, K. L. I.; Qusba, L.; Ruggiero, K.; Spitzer, W.; Stylinski, C.
2016-12-01
The Climate Literacy and Energy Awareness Network (CLEAN) was formed in 2008 to help climate and energy literacy stakeholders implement the Climate and Energy Literacy Essential Principles to enable effective and responsible decisions with regard to actions that may affect climate. The ongoing conversations of the CLEAN Network have cultivated a culture of shared resources and expertise and allowed for the development of collective impact strategies. However, it has become clear that to accelerate and scale change, effective mitigation, adaptation, and resilience strategies must be developed by a diverse network of stakeholders at the community level to deal with the local impacts of climate change and move toward decarbonized and resilient economies. A group of CLEAN Network members, experienced in establishing effective networks and representing mature climate change education programs, came together to discuss at the community level 1) how we can collectively enable larger scale efforts to 2) develop effective strategies, 3) identify gaps in the system that limit action, and 4) coordinate possible vectors for interceding to advance community level decisions related to climate. We will describe our Theory of Change, based on both the power of communities and increasing climate literacy as a key requirement for sustained progress on the crisis climate change presents. From our Theory of Change, we have begun to outline a national monitoring strategy that can provide communities a measured way to understand their local readiness to respond to the impacts of climate change and understand the magnitude of those impacts in relation to their political and ecological economies. The scale would help describe the robustness of their programs and partnerships to address those impacts, the political climate for working in advance of pending change, and the degree of citizen engagement in resilience planning and action. The goal is to provide a common tool equivalent to GDP that communities could use to see their strengths and leverage points, and where they have the local resources to build solutions or co-develop solutions with others. Though this new tool, communities may be better able to focus on mitigation, adaptation, and the building of resilience that will put into practice the identified Theory of Change.
Topography, surface features, and flooding of Rogers Lake playa, California
Dinehart, Randal L.; McPherson, Kelly R.
1998-01-01
Rogers Lake is a desert playa used as a military airport for Edwards Air Force Base in the Antelope Valley of southern California. Previous measurements of land subsidence and ground-water levels in the study area indicated that ground-water pumping induced tensional stresses in the playa, which were sporadically relieved through the formation of long cracks. Drying of the sediments beneath the playa also may have accelerated the natural formation of giant desiccation polygons. When water flows across the playa, the cracks erode into fissures of sufficient width and depth to endanger traffic on the playa. Topographic surveys of the playa were made to derive a contour map that would allow examination of erosive flow paths. Crack networks were surveyed in selected areas during 1995 and compared with cracks visible in aerial photographs taken in 1990. Crack networks remained visible in their positions following several inundations of the playa. The density of the crack networks increased in all of the selected areas.
Numerical analysis of the in-well vapor-stripping system demonstration at Edwards Air Force Base
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, M.D.; Gilmore, T.J.
1996-10-01
Numerical simulations, with the Subsurface Transport Over Multiple Phases (STOMP) simulator, were applied to the field demonstration of an in-well vapor-stripping system at Edwards Air Force Base (AFB), near Mojave, California. The demonstration field site on the Edwards AFB was previously contaminated from traversing groundwater that was contained a varied composition of volatile organic compounds (VOCs), which primarily includes trichloroethylene (TCE). Contaminant TCE originated from surface basin that had been used to collect runoff during the cleaning of experimental rocket powered planes in the 1960s and 1970s. This report documents those simulations and associated numerical analyses. A companion report documentsmore » the in- well vapor-stripping demonstration from a field perspective.« less
Fleck, W.B.; Vroblesky, D.A.
1996-01-01
Geomorphic processes and the aquatic habitat of the Redwood Creek basin were studied extensively between 1973 and 1983. This volume contains 22 separate articles by 32 investigators who studied geology, major storms, timber harvesting and its role on accelerating erosion, mass movement, fluvial erosion, sediment transport and storage, stream channel response to storms and landuse, stream habitat, and stream chemistry. This research describes a rapidly eroding landscape that is sensitive to effects of both landuse and major storms.
Schiwietz, G; Kühn, D; Föhlisch, A; Holldack, K; Kachel, T; Pontius, N
2016-09-01
A comprehensive investigation of the emission characteristics for electrons induced by X-rays of a few hundred eV at grazing-incidence angles on an atomically clean Cu(111) sample during laser excitation is presented. Electron energy spectra due to intense infrared laser irradiation are investigated at the BESSY II slicing facility. Furthermore, the influence of the corresponding high degree of target excitation (high peak current of photoemission) on the properties of Auger and photoelectrons liberated by a probe X-ray beam is investigated in time-resolved pump and probe measurements. Strong electron energy shifts have been found and assigned to space-charge acceleration. The variation of the shift with laser power and electron energy is investigated and discussed on the basis of experimental as well as new theoretical results.
NASA Astrophysics Data System (ADS)
Durham, M. C.; Milewski, A.; El Kadiri, R.
2013-12-01
The combination of natural, anthropogenic, and climate change impacts on the water resources of the Middle East and North Africa (MENA) region has devastated its water resources well beyond its current and projected populations. The increased exploitation of groundwater resources in the past half-century coupled with successive droughts has resulted in the acceleration of subsidence rates in the Souss and Massa basins in Morocco. We have completed a preliminary investigation of these impacts on the Souss and Massa basins (~27,000 km2) in the southwestern part of Morocco. This area is characterized by a semi-arid climate (annual precipitation 70-250 mm/year) with agriculture, tourism, and commercial fishing as the primary economic activities, all of which require availability of adequate freshwater resources. Additionally the primary groundwater aquifer (Plio-Quaternary Plain Aquifer), an unconfined aquifer formed mostly of sand and gravel, is being harvested by >20,000 wells at a rate of 650 MCM/yr., exceeding the rate of recharge by 260 MCM/year. Intense development over the past 50 years has exposed the aquifer to a serious risk of groundwater table drawdown (0.5m-2.5m/yr.), land subsidence, loss of artesian pressure, salinization, salt water intrusions along the coast, and deterioration of water quality across the watershed. Differential Interferometry Synthetique Aperture Radar (DInSAR) was utilized to measure ground subsidence induced by groundwater withdrawal. Land subsidence caused by excessive groundwater extraction was determined using a threefold methodology: (1) extraction of subsidence and land deformation patterns using radar interferometry, (2) correlation of the high subsidence areas within the basins to possible natural and anthropogenic factors (e.g. sea level rise, unconsolidated lithological formations distribution, urbanization, excessive groundwater extraction), and (3) forecasting the future of the Souss and Massa basins over the next century if both subsidence and groundwater extraction continue at present rates. Interferometric processing (persistent scatter and small baseline subset) was conducted using ENVI's SARscape program with 168 archived ENVISAT SLC images and 350 ERS1/2 SLC images acquired through the European Space Agency. Radar interferometry results are spatially and temporally consistent with groundwater extraction rates. This analysis has provided insight into the impacts that land subsidence will have on the infrastructure, the population, and the economy of the Souss and Massa basins. Our results could be used to develop management plans for modulating these adverse effects and could be vital to the Moroccan economy and the livelihood of the citizens that inhabit the basins. More broadly, this approach could be applied to other areas within the MENA region facing similar impacts.
Will the Arctic Land Surface become Wetter or Drier in Response to a Warming Climate
NASA Astrophysics Data System (ADS)
Hinzman, L. D.; Rawlins, M.; Serreze, M.; Vorosmarty, C. J.; Walsh, J. E.
2015-12-01
There is much concern about a potentially "accelerated" hydrologic cycle, with associated extremes in weather and climate-related phenomena. Whether this translates into wetter or drier conditions across arctic landscapes remains an open question. Arctic ecosystems differ substantially from those in temperate regions, largely due to the interactions of extremes in climate and land surface characteristics. Ice-rich permafrost prevents percolation of rainfall or snowmelt water, often maintaining a moist to saturated active layer where the permafrost table is shallow. Permafrost may also block the lateral movement of groundwater, and act as a confining unit for water in sub- or intra-permafrost aquifers. However, as permafrost degrades, profound changes in interactions between groundwater and surface water occur that affect the partitioning among the water balance components with subsequent impacts to the surface energy balance and essential ecosystem processes. Most simulations of arctic climate project sustained increases in temperature and gradual increases in precipitation over the 21st century. However, most climatic models do not correctly represent the essential controls that permafrost exerts on hydrological, ecological, and climatological processes. If warming continues as projected, we expect large-scale changes in surface hydrology as permafrost degrades. Where groundwater gradients are downward (i.e. surface water will infiltrate to subsurface groundwater), as in most cases, we may expect improved drainage and drier soils, which would result in reduced evaporation and transpiration (ET). In some special cases, where the groundwater gradient is upward (as in many wetlands or springs) surface soils may become wetter or inundated as permafrost degrades. Further, since soil moisture is a primary factor controlling ecosystem processes, interactions between ecosystems, GHG emissions, and high-latitude climate must also be considered highly uncertain. These inter-dependent processes will exert primary controls on several important feedback processes and vary across space and time in some as yet, unknown way.
Wang, Y H; Li, P; Dai, X Y; Zhang, R; Jiang, Z; Jiang, D W; Wang, Y X
2015-05-15
To investigate the community diversity and abundance of methanogens and their potential role in high arsenic groundwater, 17 groundwater samples from Hetao Plain of Inner Mongolia were investigated with an integrated method including 16S rRNA gene clone library, quantitative polymerase chain reaction and geochemistry analyses. Total arsenic (AsTot) concentrations were 82.7-1088.7 μg/L and arsenite (AsIII) mostly dominated in these samples with percentages of 0.04-0.79. CH₄ concentrations ranged from 0.01 to 292 μg/L and distinctly elevated only when AsTot were relatively high and SO₄(2-) were distinctly low. Principal component analysis indicated that these samples were divided into three groups according to the variations of AsTot, CH₄ and SO₄(2-). AsTot concentrations were distinctly high in the group with high CH₄ and low SO₄(2-) comparing to the other two groups (one with high CH₄ and high SO₄(2-), the other with low CH₄ and SO₄(2-)). The mcrA gene (methyl coenzyme-M reductase gene) based phylogenetic analysis of methanogens population showed that methanogenic archaea was diverse but mainly composed of Methanomicrobiales, Methanosarcinales, Methanobacteria and unidentified groups, with Methanomicrobiales being distinctly dominant (50.6%). The mcrA gene abundance in high arsenic groundwater ranged from 3.01 × 10(3) to 3.80 × 10(6)copies/L and accounted for 0-30.2% of total archaeal 16S rRNA genes. The abundance of mcrA genes was positively correlated with the concentrations of AsTot (R=0.59), AsIII (R=0.57) and FeII (R=0.79), while it was negatively correlated with oxidation-reduction potential (R=-0.66) and SO₄(2-) concentration (R=-0.64). These results implied that methanogenic archaea might accelerate As release in groundwater aquifers in Hetao Plain. Copyright © 2015. Published by Elsevier B.V.
Bai, Yaohui; Chang, Yangyang; Liang, Jinsong; Chen, Chen; Qu, Jiuhui
2016-12-01
High concentrations of iron (Fe(II)) and manganese (Mn(II)) often occur simultaneously in groundwater. Previously, we demonstrated that Fe(II) and Mn(II) could be oxidized to biogenic Fe-Mn oxides (BFMO) via aeration and microbial oxidation, and the formed BFMO could further oxidize and adsorb other pollutants (e.g., arsenic (As(III)) and antimony (Sb(III))). To apply this finding to groundwater remediation, we established four quartz-sand columns for treating groundwater containing Fe(II), Mn(II), As(III), and Sb(III). A Mn-oxidizing bacterium (Pseudomonas sp. QJX-1) was inoculated into two parallel bioaugmented columns. Long-term treatment (120 d) showed that bioaugmentation accelerated the formation of Fe-Mn oxides, resulting in an increase in As and Sb removal. The bioaugmented columns also exhibited higher overall treatment effect and anti-shock load capacity than that of the non-bioaugmented columns. To clarify the causal relationship between the microbial community and treatment effect, we compared the biomass of active bacteria (reverse-transcribed real-time PCR), bacterial community composition (Miseq 16S rRNA sequencing) and community function (metagenomic sequencing) between the bioaugmented and non-bioaugmented columns. Results indicated that the QJX1 strain grew steadily and attached onto the filter material surface in the bioaugmented columns. In general, the inoculated strain did not significantly alter the composition of the indigenous bacterial community, but did improve the relative abundances of xenobiotic metabolism genes and Mn oxidation gene. Thus, bioaugmentation intensified microbial degradation/utilization for the direct removal of pollutants and increased the formation of Fe-Mn oxides for the indirect removal of pollutants. Our study provides an alternative method for the treatment of groundwater containing high Fe(II), Mn(II) and As/Sb. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Vengosh, Avner; Kloppmann, Wolfram; Marei, Amer; Livshitz, Yakov; Gutierrez, Alexis; Banna, Mazen; Guerrot, Catherine; Pankratov, Irena; Raanan, Hadas
2005-01-01
Salinization in coastal aquifers is a global phenomenon resulting from the overexploitation of scarce water resources. The Gaza Strip is one of the most severe cases of salinization, as accelerated degradation of the water quality endangers the present and future water supply for over 1 million people. We investigate the chemical and isotopic (87Sr/86Sr, δ11B, δ18O, δ2H, and δ34SSO4) compositions of groundwater from the southern Mediterranean coastal aquifer (Israel) and the Gaza Strip in order to elucidate the origin of salinity and boron contamination. The original salinity in the eastern part of the aquifer is derived from discharge of saline groundwater from the adjacent Avedat aquitard (Na/Cl < 1, 87Sr/86Sr ˜ 0.7079, and δ11B ˜ 40‰). As the groundwater flows to the central part of the aquifer, a dramatic change in its composition occurs (Na/Cl > 1, high B/Cl, SO4/Cl, and HCO3, 87Sr/86Sr ˜ 0.7083; δ11B ˜ 48‰), although the δ18O-δ2H slope is identical to that of the Avedat aquitard. The geochemical data suggest that dissolution of pedogenic carbonate and gypsum minerals in the overlying loessial sequence generated the Ca-rich solution that triggered base exchange reactions and produced Na- and B-rich groundwater. The geochemical data show that most of the salinization process in the Gaza Strip is derived from the lateral flow of the Na-rich saline groundwater, superimposed with seawater intrusion and anthropogenic nitrate pollution. The methodology of identification of multiple salinity sources can be used to establish a long-term management plan for the Gaza Strip and can also be implemented to understand complex salinization processes in other similarly stressed coastal aquifers.
NASA Astrophysics Data System (ADS)
Vengosh, Avner; Kloppmann, Wolfram; Marei, Amer; Livshitz, Yakov; Gutierrez, Alexis; Banna, Mazen; Guerrot, Catherine; Pankratov, Irena; Raanan, Hadas
2005-01-01
Salinization in coastal aquifers is a global phenomenon resulting from the overexploitation of scarce water resources. The Gaza Strip is one of the most severe cases of salinization, as accelerated degradation of the water quality endangers the present and future water supply for over 1 million people. We investigate the chemical and isotopic (87Sr/86Sr, δ11B, δ18O, δ2H, and δ34SSO4) compositions of groundwater from the southern Mediterranean coastal aquifer (Israel) and the Gaza Strip in order to elucidate the origin of salinity and boron contamination. The original salinity in the eastern part of the aquifer is derived from discharge of saline groundwater from the adjacent Avedat aquitard (Na/Cl < 1, 87Sr/86Sr ~ 0.7079, and δ11B ~ 40‰). As the groundwater flows to the central part of the aquifer, a dramatic change in its composition occurs (Na/Cl > 1, high B/Cl, SO4/Cl, and HCO3, 87Sr/86Sr ~ 0.7083; δ11B ~ 48‰), although the δ18O-δ2H slope is identical to that of the Avedat aquitard. The geochemical data suggest that dissolution of pedogenic carbonate and gypsum minerals in the overlying loessial sequence generated the Ca-rich solution that triggered base exchange reactions and produced Na- and B-rich groundwater. The geochemical data show that most of the salinization process in the Gaza Strip is derived from the lateral flow of the Na-rich saline groundwater, superimposed with seawater intrusion and anthropogenic nitrate pollution. The methodology of identification of multiple salinity sources can be used to establish a long-term management plan for the Gaza Strip and can also be implemented to understand complex salinization processes in other similarly stressed coastal aquifers.
NASA Astrophysics Data System (ADS)
Rusteberg, Bernd; Azizur Rahman, M.; Abusaada, Muath; Rabi, Ayman; Rahman Tamimi, A.; Sauter, Martin
2010-05-01
The water resources in Gaza Strip are currently facing extreme over-exploitation which has led to a sharp decline of the groundwater level in this Mediterranean coastal aquifer overtime. Salinity of the groundwater is very high as a result of subsequent seawater intrusion of the aquifer. The contamination of the Gaza Strip groundwater by seawater has wide-ranging effects on the regional economy as well as agricultural productivity. In order to guarantee the sustainability of regional development, which requires the access to clean water, groundwater artificial recharge (AR) is being considered as a potential solution to this current water resources problem. The objective of the present study is to analyze several strategies for the implementation and management of AR in Gaza Strip and their potential impacts on agriculture, environment, and the socio-economy. Based on the water policy on wastewater reclamation and reuse (Yr. 2005 - 2025), six AR management strategies were developed in close cooperation with the local stakeholder community. These scenarios take into consideration the development of the new North Gaza Wastewater Treatment Plant and were also judged with respect to a base-line scenario, otherwise known as the "Do Nothing Approach." Multi-Criteria Decision Analysis (MCDA) on ranking of the AR management scenarios was used. Twenty-one criteria ranging over a wide spectrum and four categories (Environmental, Public Health, Social, and Economical) were defined to ensure sound evaluation of each of the six AR management scenarios. A detailed geo-database was prepared to analyze all the related spatial, non-spatial, and temporal data. Socio-economic studies, field surveys, mathematical modeling, and GIS analysis were used for the criteria quantification. In the MCDA, Analytical Hierarchy Method (AHP) combined with weighted Linear Combination (WLC) and Composite Programming (CP) was employed. The six AR management strategies were thus compared to the "Do Nothing Approach" based on the defined environmental, health, social, and economical criteria, the most important being related to the environment and the economy. The robustness of the achieved ranking of AR management options has been tested by changing the selected criteria, criteria importance and criteria structure. The final analysis shows that all six AR management strategies are better than "doing nothing". The implementation of groundwater artificial recharge with maximum possible infiltration of secondary treated effluent in conjunction with sustainable reuse of the recharged water for agricultural development is the most effective AR solution to the water resources problems of the Gaza Strip.
Experiments and PIC simulations on liquid crystal plasma mirrors for pulse contrast enhancement
NASA Astrophysics Data System (ADS)
Cochran, G. E.; Poole, P. L.; Krygier, A.; Foster, P. S.; Scott, G. G.; Wilson, L. A.; Bailey, J.; Bourgeois, N.; Hernandez-Gomez, C.; Heery, R.; Purcell, J.; Neely, D.; Rajeev, P. P.; Freeman, R. R.; Schumacher, D. W.
2016-10-01
High pulse contrast is crucial for performing many experiments on high intensity lasers in order to minimize modification of the target surface by pre-pulse. This is often achieved through the use of solid dielectric plasma mirrors which can limit laser shot rates. Liquid crystal films, originally developed as variable thickness ion acceleration targets, have been demonstrated as effective plasma mirrors for pulse cleaning, reaching peak reflectivities over 70%. These films were used as plasma mirrors in an ion acceleration experiment on the Scarlet laser and the resultant increase in peak proton energy and change in acceleration direction will be discussed. Also presented here are novel 2D3V, LSP particle-in-cell simulations of dielectric plasma mirror operation. By including multiphoton ionization and dimensionality corrections, an excellent match to experiment is obtained over 4 decades in intensity. Analysis of pulse shortening and plasma critical surface behavior in these simulations will be discussed. Formation of thin films at 1.5 Hz will also be presented. Performed with support from the DARPA PULSE program through AMRDEC, from NNSA, and from OSC.
Industrialization of Superconducting RF Accelerator Technology
NASA Astrophysics Data System (ADS)
Peiniger, Michael; Pekeler, Michael; Vogel, Hanspeter
2012-01-01
Superconducting RF (SRF) accelerator technology has basically existed for 50 years. It took about 20 years to conduct basic R&D and prototyping at universities and international institutes before the first superconducting accelerators were built, with industry supplying complete accelerator cavities. In parallel, the design of large scale accelerators using SRF was done worldwide. In order to build those accelerators, industry has been involved for 30 years in building the required cavities and/or accelerator modules in time and budget. To enable industry to supply these high tech components, technology transfer was made from the laboratories in the following three regions: the Americas, Asia and Europe. As will be shown, the manufacture of the SRF cavities is normally accomplished in industry whereas the cavity testing and module assembly are not performed in industry in most cases, yet. The story of industrialization is so far a story of customized projects. Therefore a real SRF accelerator product is not yet available in this market. License agreements and technology transfer between leading SRF laboratories and industry is a powerful tool for enabling industry to manufacture SRF components or turnkey superconducting accelerator modules for other laboratories and users with few or no capabilities in SRF technology. Despite all this, the SRF accelerator market today is still a small market. The manufacture and preparation of the components require a range of specialized knowledge, as well as complex and expensive manufacturing installations like for high precision machining, electron beam welding, chemical surface preparation and class ISO4 clean room assembly. Today, the involved industry in the US and Europe comprises medium-sized companies. In Japan, some big enterprises are involved. So far, roughly 2500 SRF cavities have been built by or ordered from industry worldwide. Another substantial step might come from the International Linear Collider (ILC) project currently being designed by the international collaboration GDE (`global design effort'). If the ILC will be built, about 18,000 SRF cavities need to be manufactured worldwide within about five years. The industrialization of SRF accelerator technology is analyzed and reviewed in this article in view of the main accelerator projects of the last two to three decades.
Hydrologic resources management program and underground test area FY 1999 progress report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, D K; Eaton, G F; Rose, T P
2000-07-01
This report presents the results from fiscal year (FY) 1999 technical studies conducted by Lawrence Livermore National Laboratory (LLNL) as part of the Hydrology and Radionuclide Migration Program (HRMP) and Underground Test Area (UGTA) work-for-others project. This report is the latest in a series of annual reports published by LLNL to document the migration of radionuclides and controls of radionuclide movement at the Nevada Test Site. The FY 1999 studies highlighted in this report are: (1) Chapter 1 provides the results from flow-through leaching of nuclear melt glasses at 25 C and near-neutral pH using dilute bicarbonate groundwaters. (2) Chaptermore » 2 reports on a summary of the size and concentration of colloidal material in NTS groundwaters. (3) Chapter 3 discusses the collaboration between LLNL/ANCD (Analytical and Nuclear Chemistry Division) and the Center for Accelerator Mass Spectrometry (CAMS) to develop a technique for analyzing NTS groundwater for 99-Technicium ({sup 99}Tc) using accelerator mass spectrometry (AMS). Since {sup 99}Tc is conservative like tritium in groundwater systems, and is not sorbed to geologic material, it has the potential for being an important tool for radionuclide migration studies. (4) Chapter 4 presents the results of secondary ion mass spectrometry measurements of the in-situ distribution of radionuclides in zeolitized tuffs from cores taken adjacent to nuclear test cavities and chimneys. In-situ measurements provide insight to the distribution of specific radionuclides on a micro-scale, mineralogical controls of radionuclide sorption, and identification of migration pathways (i.e., matrix diffusion, fractures). (5) Chapter 5 outlines new analytical techniques developed in LLNL/ANCD to study hydrologic problems at the NTS using inductively coupled plasma mass spectrometry (ICP-MS). With costs for thermal-ionization mass spectrometry (TIMS) increasing relative to sample preparation time and facility support, ICP-MS technology provides a means for rapidly measuring dilute concentrations of radionuclides with precision and abundance sensitivity comparable to TIMS. (6) Chapter 6 provides results of a characterization study of alluvium collected from the U-1a complex approximately 300 meters below ground surface in Yucca Flat. The purpose of this investigation was to provide information on particle size, mineralogical context, the proportion of primary and secondary minerals, and the texture of the reactive surface area that could be used to accurately model radionuclide interactions within Nevada Test Site alluvial basins (i.e., Frenchman Flat and Yucca Flat).« less
Microstructured snow targets for high energy quasi-monoenergetic proton acceleration
NASA Astrophysics Data System (ADS)
Schleifer, E.; Nahum, E.; Eisenmann, S.; Botton, M.; Baspaly, A.; Pomerantz, I.; Abricht, F.; Branzel, J.; Priebe, G.; Steinke, S.; Andreev, A.; Schnuerer, M.; Sandner, W.; Gordon, D.; Sprangle, P.; Ledingham, K. W. D.; Zigler, A.
2013-05-01
Compact size sources of high energy protons (50-200MeV) are expected to be key technology in a wide range of scientific applications 1-8. One promising approach is the Target Normal Sheath Acceleration (TNSA) scheme 9,10, holding record level of 67MeV protons generated by a peta-Watt laser 11. In general, laser intensity exceeding 1018 W/cm2 is required to produce MeV level protons. Another approach is the Break-Out Afterburner (BOA) scheme which is a more efficient acceleration scheme but requires an extremely clean pulse with contrast ratio of above 10-10. Increasing the energy of the accelerated protons using modest energy laser sources is a very attractive task nowadays. Recently, nano-scale targets were used to accelerate ions 12,13 but no significant enhancement of the accelerated proton energy was measured. Here we report on the generation of up to 20MeV by a modest (5TW) laser system interacting with a microstructured snow target deposited on a Sapphire substrate. This scheme relax also the requirement of high contrast ratio between the pulse and the pre-pulse, where the latter produces the highly structured plasma essential for the interaction process. The plasma near the tip of the snow target is subject to locally enhanced laser intensity with high spatial gradients, and enhanced charge separation is obtained. Electrostatic fields of extremely high intensities are produced, and protons are accelerated to MeV-level energies. PIC simulations of this targets reproduce the experimentally measured energy scaling and predict the generation of 150 MeV protons from laser power of 100TW laser system18.
Ottonello, Giuliana; Ferrari, Angelo; Magi, Emanuele
2014-01-01
A simple and robust method for the determination of 18 polychlorinated biphenyls (PCBs) in fish was developed and validated. A mixture of acetone/n-hexane (1:1, v/v) was selected for accelerated solvent extraction (ASE). After the digestion of fat, the clean-up was carried out using solid phase extraction silica cartridges. Samples were analysed by GC-MS in selected ion monitoring (SIM) using three fragment ions for each congener (one quantifier and two qualifiers). PCB 155 and PCB 198 were employed as internal standards. The lowest limit of detection was observed for PCB 28 (0.4ng/g lipid weight). The accuracy of the method was verified by means of the Certified Reference Material EDF-2525 and good results in terms of linearity (R(2)>0.994) and recoveries (80-110%) were also achieved. Precision was evaluated by spiking blank samples at 4, 8 and 12ng/g. Relative standard deviation values for repeatability and reproducibility were lower than 8% and 16%, respectively. The method was applied to the determination of PCBs in 80 samples belonging to four Mediterranean fish species. The proposed procedure is particularly effective because it provides good recoveries with lowered extraction time and solvent consumption; in fact, the total time of extraction is about 12min per sample and, for the clean-up step, a total solvent volume of 13ml is required. Copyright © 2013 Elsevier Ltd. All rights reserved.
Chiesa, Luca Maria; Labella, Giuseppe Federico; Panseri, Sara; Britti, Domenico; Galbiati, Fabrizio; Villa, Roberto; Arioli, Francesco
2017-05-01
The worldwide loss of honeybee colonies may be due to their exposure to several contaminants (i.e., pesticides); such contamination may also have impacts on consumers' health. Therefore, it is essential to develop quick and new methods to detect several pesticide residues in honey samples. In this study, the effectiveness of accelerated solvent extraction (ASE) was compared with QuEChERS methods for the analysis of 53 pesticides in organic honey by gas chromatography-triple quadrupole mass spectrometry. Two simple and rapid ASE methods with 'in-line' clean-up were optimised and then compared with QuEChERS. Hexane-ethyl acetate (Hex:EtAc) and Florisil were chosen as extraction solvent and retainer for the first ASE method respectively; acetonitrile and a primary-secondary amine phase (ACN-PSA) were selected for the second ASE method. The methods were validated according to the European Union SANTE/11945/2015 guidelines. The validation parameters showed that QuEChERS and ASE with PSA as retainer had better repeatability than ASE with Hex:EtAc and Florisil. In particular, QuEChERS and ASE (ACN-PSA) showed good recovery, according to the SANTE criteria, for the majority of investigated pesticides. Conversely, when ASE with Hex:EtAc and Florisil was used as the retainer, several compounds showed recoveries lower than the acceptable value of 70%. The ASE in-line method was finally applied to evaluate pesticide concentration in organic honey samples.
NASA Astrophysics Data System (ADS)
Schmitt, R. J. P.; Rubin, Z.; Kondolf, G. M.
2017-10-01
With changing climate and rising seas, proliferation of hydroelectric dams, instream sand mining, dyking of floodplains, accelerated subsidence from groundwater pumping, accelerated sea-level rise, and other anthropic impacts, it is certain that the Mekong Delta will undergo large changes in the coming decades. These changes will threaten the very existence of the landform itself. The multiplicity of compounding drivers and lack of reliable data lead to large uncertainties in forecasting changes in the sediment budget of the Mekong Delta, its morphology, and the ecosystems and human livelihoods it supports. We compile information on key drivers affecting the sediment budget of the Mekong Delta and compare them to quantify the magnitude of effects from different drivers. We develop a set of likely scenarios for the future development of these drivers and quantify implications for the future of the Mekong Delta using a simplified model of the delta's geometry. If sediment supply to the delta is nearly completely cut off, as would be the case with full buildout of planned dams and current rates of sediment mining, and with continued groundwater pumping at current rates, our model forecasts that the delta will almost completely disappear by the end of this century due to increased rates of delta subsidence and rising sea levels. While local management cannot prevent global sea level rise, model results suggest that there are important management steps that could prolong the persistence of the delta ecosystem and the livelihoods it supports, including a reduction in ground water pumping and maintaining sediment connectivity between the basin and the delta.
Natural iodine-129 as an environmental tracer
NASA Astrophysics Data System (ADS)
Fabryka-Martin, J.; Bentley, H.; Elmore, D.; Airey, P. L.
1985-02-01
Iodine-129 ( t 1/2, 16 My) is a naturally-occurring tracer which can be used to study hydrologic and geologic processes on time scales up to 100 My. The pre-bomb atmospheric ratio 129I /I should have been constant in time and space and is the starting value in ground-water recharge. Subsequent ratio changes in ground water should be determined by isotope contributions from three sources: recharge water, iodine leached from the formation, and in situ uranium fission. The mathematical expression of these time-dependent processes forms the basis for dating and tracing applications. The expected behavior of natural 129I in ground water is compared to results from field studies. Ground-water samples from the Great Artesian Basin, Australia, provide an estimate of the atmospheric equilibrium ratio, 6 × 10 -13. Down-gradient changes in water up to 1 My old suggest that subsurface production can be significant. The usefulness of 129I as an indicator of brine source and age is verified in brines collected in and around Louisiana salt domes. The method leads to ages of 7 and 9 My for two brine pockets trapped within Jurassic salt, and 32 to >40 My for oil-field brines in Miocene sands adjacent to the domes. The results demonstrate the capability of tandem accelerator mass spectrometry to measure as few as 10 7 atoms of 129I in 10 mg I with 10% precision. Although such atom sensitivity can be achieved otherwise, the accelerator technique is necessary to measure naturally low pre-1945 cosmogenic isotope ratios.
NASA Astrophysics Data System (ADS)
Corseuil, Henry Xavier; Gomez, Diego E.; Schambeck, Cássio Moraes; Ramos, Débora Toledo; Alvarez, Pedro J. J.
2015-03-01
A comparison of two controlled ethanol-blended fuel releases under monitored natural attenuation (MNA) versus nitrate biostimulation (NB) illustrates the potential benefits of augmenting the electron acceptor pool with nitrate to accelerate ethanol removal and thus mitigate its inhibitory effects on BTEX biodegradation. Groundwater concentrations of ethanol and BTEX were measured 2 m downgradient of the source zones. In both field experiments, initial source-zone BTEX concentrations represented less than 5% of the dissolved total organic carbon (TOC) associated with the release, and measurable BTEX degradation occurred only after the ethanol fraction in the multicomponent substrate mixture decreased sharply. However, ethanol removal was faster in the nitrate amended plot (1.4 years) than under natural attenuation conditions (3.0 years), which led to faster BTEX degradation. This reflects, in part, that an abundant substrate (ethanol) can dilute the metabolic flux of target pollutants (BTEX) whose biodegradation rate eventually increases with its relative abundance after ethanol is preferentially consumed. The fate and transport of ethanol and benzene were accurately simulated in both releases using RT3D with our general substrate interaction module (GSIM) that considers metabolic flux dilution. Since source zone benzene concentrations are relatively low compared to those of ethanol (or its degradation byproduct, acetate), our simulations imply that the initial focus of cleanup efforts (after free-product recovery) should be to stimulate the degradation of ethanol (e.g., by nitrate addition) to decrease its fraction in the mixture and speed up BTEX biodegradation.
Corseuil, Henry Xavier; Gomez, Diego E; Schambeck, Cássio Moraes; Ramos, Débora Toledo; Alvarez, Pedro J J
2015-03-01
A comparison of two controlled ethanol-blended fuel releases under monitored natural attenuation (MNA) versus nitrate biostimulation (NB) illustrates the potential benefits of augmenting the electron acceptor pool with nitrate to accelerate ethanol removal and thus mitigate its inhibitory effects on BTEX biodegradation. Groundwater concentrations of ethanol and BTEX were measured 2 m downgradient of the source zones. In both field experiments, initial source-zone BTEX concentrations represented less than 5% of the dissolved total organic carbon (TOC) associated with the release, and measurable BTEX degradation occurred only after the ethanol fraction in the multicomponent substrate mixture decreased sharply. However, ethanol removal was faster in the nitrate amended plot (1.4 years) than under natural attenuation conditions (3.0 years), which led to faster BTEX degradation. This reflects, in part, that an abundant substrate (ethanol) can dilute the metabolic flux of target pollutants (BTEX) whose biodegradation rate eventually increases with its relative abundance after ethanol is preferentially consumed. The fate and transport of ethanol and benzene were accurately simulated in both releases using RT3D with our general substrate interaction module (GSIM) that considers metabolic flux dilution. Since source zone benzene concentrations are relatively low compared to those of ethanol (or its degradation byproduct, acetate), our simulations imply that the initial focus of cleanup efforts (after free-product recovery) should be to stimulate the degradation of ethanol (e.g., by nitrate addition) to decrease its fraction in the mixture and speed up BTEX biodegradation. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Lee, Jin-Yong; Cheon, Jeong-Yong; Lee, Kang-Kun; Lee, Seok-Young; Lee, Min-Hyo
2001-07-01
The distributions of hydrocarbon contaminants and hydrogeochemical parameters were investigated in a shallow sand aquifer highly contaminated with petroleum hydrocarbons leaked from solvent storage tanks. For these purposes, a variety of field investigations and studies were performed, which included installation of over 100 groundwater monitoring wells and piezometers at various depths, soil logging and analyses during well and piezometer installation, chemical analysis of groundwater, pump tests, and slug tests. Continuous water level monitoring at three selected wells using automatic data-logger and manual measuring at other wells were also conducted. Based on analyses of the various investigations and tests, a number of factors were identified to explain the distribution of the hydrocarbon contaminants and hydrogeochemical parameters. These factors include indigenous biodegradation, hydrostratigraphy, preliminary pump-and-treat remedy, recharge by rainfall, and subsequent water level fluctuation. The permeable sandy layer, in which the mean water table elevation is maintained, provided a dominant pathway for contaminant transport. The preliminary pump-and-treat action accelerated the movement of the hydrocarbon contaminants and affected the redox evolution pattern. Seasonal recharge by rain, together with indigenous biodegradation, played an important role in the natural attenuation of the petroleum hydrocarbons via mixing/dilution and biodegradation. The water level fluctuations redistributed the hydrocarbon contaminants by partitioning them into the soil and groundwater. The identified factors are not independent but closely inter-correlated.
Long-term migration of iodine in sedimentary rocks based on iodine speciation and 129I/127I ratio
NASA Astrophysics Data System (ADS)
Togo, Y.; Takahashi, Y.; Amano, Y.; Matsuzaki, H.; Suzuki, Y.; Muramatsu, Y.; Iwatsuki, T.
2012-12-01
[Introduction] 129I is one of the available indexes of long-term migration of groundwater solutes, because of its long half-life (15.7 million years) and low sorption characteristics. The Horonobe underground research center (Japan Atomic Energy Agency), at which are conducted research and development of fundamental techniques on geological disposal of high-level radioactive waste, is an appropriate site for natural analogue studies, because iodine concentration in groundwater is high in this area. To predict iodine behavior in natural systems, speciation of iodine is essential because of different mobility among each species. In this study, we determined iodine speciation and129I/127I isotope ratios of rock and groundwater samples to investigate long term migration of iodine. [Methods] All rock and groundwater samples were collected at Horonobe underground research center. The region is underlain mainly by Neogene to Quaternary marine sedimentary rocks, the Wakkanai Formation (Wk Fm, siliceous mudstones), and the overlying Koetoi Formation (Kt Fm, diatomaceous mudstones). Iodine species in rock samples were determined by iodine K-edge X-ray absorption near edge structure (SPring-8 BL01B1). Thin sections of rock samples were prepared, and iodine mapping were obtained by micro-XRF analysis (SPring-8 BL37XU). Iodine species (IO3-, I-, and organic I) in groundwater were separately detected by high performance liquid chromatography connected to ICP-MS. The 129I/127I ratios in groundwater and rock samples were measured by accelerator mass spectrometry (MALT, Univ. of Tokyo). Iodine in rock samples were separated by pyrohydrolysis and water extraction. [Results and discussion] Concentration of iodine in groundwater varied widely and was much higher than that of seawater showing a high correlation with that of chlorine (R2 = 0.90). Species of iodine in groundwater was mainly I-. Iodine in rock samples decreased near the boundary between Wk and Kt Fms. Iodine K-edge XANES showed that iodine in rock was a mixture of organic and inorganic iodine. According to iodine and carbon mapping in micrometer scale, iodine was accumulated locally and correlated with carbon, suggesting that iodine existed as organic iodine. The 129I/127I isotope ratios in groundwater were lower than those in rocks and almost constant at various depths, demonstrating that iodine in groundwater was released from layers deeper than co-existing rocks. According to these results, migration of iodine in this area can be expected as follows. (i) During sedimentation of Wk and Kt Fms, iodine was accumulated as organic iodine in siliceous sediments. (ii) Iodine was released as I- from the layers deeper than Wk Fm during diagenetic processes. Subsequently, iodine rich groundwater was distributed to Wk and Kt Fms due to the compaction of the layers. (iii) During uplift and denudation processes, both iodine and chlorine were diluted by meteoric water from the surface. Iodine distribution coefficient (Kd = [I concentration in rock]/[I concentration in groundwater]) of Kt Fm is higher than that in Wk Fm. Diatomaceous mudstones might be more effective than siliceous mudstones as natural barrier for 129I released from deep underground radioactive waste repository. This suggestion should be reinforced by laboratory experiments in future studies.
Golkarian, Ali; Naghibi, Seyed Amir; Kalantar, Bahareh; Pradhan, Biswajeet
2018-02-17
Ever increasing demand for water resources for different purposes makes it essential to have better understanding and knowledge about water resources. As known, groundwater resources are one of the main water resources especially in countries with arid climatic condition. Thus, this study seeks to provide groundwater potential maps (GPMs) employing new algorithms. Accordingly, this study aims to validate the performance of C5.0, random forest (RF), and multivariate adaptive regression splines (MARS) algorithms for generating GPMs in the eastern part of Mashhad Plain, Iran. For this purpose, a dataset was produced consisting of spring locations as indicator and groundwater-conditioning factors (GCFs) as input. In this research, 13 GCFs were selected including altitude, slope aspect, slope angle, plan curvature, profile curvature, topographic wetness index (TWI), slope length, distance from rivers and faults, rivers and faults density, land use, and lithology. The mentioned dataset was divided into two classes of training and validation with 70 and 30% of the springs, respectively. Then, C5.0, RF, and MARS algorithms were employed using R statistical software, and the final values were transformed into GPMs. Finally, two evaluation criteria including Kappa and area under receiver operating characteristics curve (AUC-ROC) were calculated. According to the findings of this research, MARS had the best performance with AUC-ROC of 84.2%, followed by RF and C5.0 algorithms with AUC-ROC values of 79.7 and 77.3%, respectively. The results indicated that AUC-ROC values for the employed models are more than 70% which shows their acceptable performance. As a conclusion, the produced methodology could be used in other geographical areas. GPMs could be used by water resource managers and related organizations to accelerate and facilitate water resource exploitation.
How does natural groundwater flow affect CO2 dissolution in saline aquifers?
NASA Astrophysics Data System (ADS)
Rosenzweig, R.; Michel-Meyer, I.; Tsinober, A.; Shavit, U.
2017-12-01
The dissolution of supercritical CO2 in aquifer brine is one of the most important trapping mechanisms in CO2 geological storage. Diffusion-limited dissolution is a very slow process. However, since the CO2-rich water is slightly denser than the CO2-free water, when CO2-free water is overlaid by heavier CO2-rich water, convective instability results in fingers of dense CO2-rich water that propagate downwards, causing CO2-unsaturated water to move upwards. This convection process significantly accelerates the dissolution rate of CO2 into the aquifer water.Most previous works have neglected the effect of natural groundwater flow and assumed it has no effect on the dissolution dynamics. However, it was found that in some of the saline aquifers groundwater flow rate, although small, is not zero. In this research, we study the effect of groundwater flow on dissolution by performing laboratory experiments in a bead pack cell using a mixture of methanol and ethylene-glycol as a CO2 analog while varying the water horizontal flow rate. We find that water horizontal flow decreases the number of fingers, their wavelength and their propagation velocity. When testing high water flow rates, no fingers were developed and the dissolution process was entirely diffusive. The effect of water flow on the dissolution rate did not show a clear picture. When increasing the horizontal flow rate the convective dissolution flux slightly decreased and then increased again. It seems that the combination of density-driven flow, water horizontal flow, mechanical dispersion and molecular diffusion affect the dissolution rate in a complex and non-monotonic manner. These intriguing dynamics should be further studied to understand their effect on dissolution trapping.
Burns, Erick; Gannett, Marshall W.; Sherrod, David R.; Keith, Mackenzie K.; Curtis, Jennifer A.; Bartolino, James R.; Engott, John A.; Scandella, Benjamin P.; Stern, Michelle A.; Flint, Alan L.
2017-01-01
Sufficient temperatures to generate steam likely exist under most of the dominantly volcanic terrains of southeast Oregon, northeast California, and southeast Idaho, USA, but finding sufficient permeability to allow efficient advective heat exchange is an outstanding challenge. A new thematic interpretation of existing state-level geologic maps provides an updated and refined distribution of the composition and age of geologic units for the purposes of assessing the implications for measurement and development of geothermal resources. This interpretation has been developed to better understand geothermal and hydrologic resources of the region. Comparison of the new geologic categories with available hydrologic data shows that younger volcanogenic terrains tend to have higher primary permeability than older terrains. Decrease in primary permeability with age is attributable to weathering and hydrothermal alteration of volcanogenic deposits to pore-filling clays and deposition of secondary deposits (e.g., zeolites). Spring density as a function of geology and precipitation can be used to infer groundwater flow path length within the upper aquifers. Beneath the upper aquifers, we postulate that, due to accelerated hydrothermal alteration at temperatures ~>30 °C, primary permeability at depths of geothermal interest will be limited, and that secondary permeability is a more viable target for hydrothermal fluid withdrawal. Because open fractures resulting from tensile stresses will affect all geologic layers, regions with a significant amount of groundwater flow through shallow, structurally controlled secondary permeability may overlay zones of deep secondary permeability. Regardless of whether the shallow permeability is connected with the deep permeability, shallow groundwater flow can mask the presence of deep hydrothermal flow, resulting in blind geothermal systems. Ideally, hydraulic connectivity between shallow and deep secondary permeability is limited, so that shallow groundwater does not cool potential geothermal reservoirs.
Haines, Andy; Smith, Kirk R; Anderson, Dennis; Epstein, Paul R; McMichael, Anthony J; Roberts, Ian; Wilkinson, Paul; Woodcock, James; Woods, Jeremy
2007-10-06
The absence of reliable access to clean energy and the services it provides imposes a large disease burden on low-income populations and impedes prospects for development. Furthermore, current patterns of fossil-fuel use cause substantial ill-health from air pollution and occupational hazards. Impending climate change, mainly driven by energy use, now also threatens health. Policies to promote access to non-polluting and sustainable sources of energy have great potential both to improve public health and to mitigate (prevent) climate disruption. There are several technological options, policy levers, and economic instruments for sectors such as power generation, transport, agriculture, and the built environment. However, barriers to change include vested interests, political inertia, inability to take meaningful action, profound global inequalities, weak technology-transfer mechanisms, and knowledge gaps that must be addressed to transform global markets. The need for policies that prevent dangerous anthropogenic interference with the climate while addressing the energy needs of disadvantaged people is a central challenge of the current era. A comprehensive programme for clean energy should optimise mitigation and, simultaneously, adaption to climate change while maximising co-benefits for health--eg, through improved air, water, and food quality. Intersectoral research and concerted action, both nationally and internationally, will be required.
Comparison of culture and qPCR methods in detection of mycobacteria from drinking waters.
Räsänen, Noora H J; Rintala, Helena; Miettinen, Ilkka T; Torvinen, Eila
2013-04-01
Environmental mycobacteria are common bacteria in man-made water systems and may cause infections and hypersensitivity pneumonitis via exposure to water. We compared a generally used cultivation method and a quantitative polymerase chain reaction (qPCR) method to detect mycobacteria in 3 types of drinking waters: surface water, ozone-treated surface water, and groundwater. There was a correlation between the numbers of mycobacteria obtained by cultivation and qPCR methods, but the ratio of the counts obtained by the 2 methods varied among the types of water. The qPCR counts in the drinking waters produced from surface or groundwater were 5 to 34 times higher than culturable counts. In ozone-treated surface waters, both methods gave similar counts. The ozone-treated drinking waters had the highest concentration of assimilable organic carbon, which may explain the good culturability. In warm tap waters, qPCR gave 43 times higher counts than cultivation, but both qPCR counts and culturable counts were lower than those in the drinking waters collected from the same sites. The TaqMan qPCR method is a rapid and sensitive tool for total quantitation of mycobacteria in different types of clean waters. The raw water source and treatments affect both culturability and total numbers of mycobacteria in drinking waters.
Cold-water refuges for climate resilience in Oregon coastal ...
Many rivers and streams in the Pacific Northwest are currently listed as impaired under the Clean Water Act as a result of high summer water temperatures. Adverse effects of warm waters include impacts to salmon and steelhead populations that may already be stressed by habitat alteration, disease, predation, and fishing pressures. Thermal refuges may help mitigate the effects of increasing temperatures. In this presentation, we define cold-water refuges as areas buffered from regional climate effects by groundwater, physical habitat heterogeneity, or other watershed attributes. Processes forming these features include groundwater-surface water interactions, and hyporheic exchange at a range of spatial and temporal scales. Patterns associated with these processes may provide useful indicators for mapping and predicting the locations and extent of these features. Fish may congregate at high densities within cold-water refuges during critical periods of thermal stress, but there may be trade-offs associated with refuge use including predation, disease risk, and reduced foraging opportunities. These factors all contribute to determining refuge effectiveness. Watershed management and restoration strategies could consider these features and their potential utility to cold-water fish, and we conclude with examples of types of watershed restoration actions that might help foster cold-water refuge creation and maintenance.M Many rivers and streams in the Pacific Nort
Electro-chemical arsenic remediation: field trials in West Bengal.
Amrose, Susan E; Bandaru, Siva R S; Delaire, Caroline; van Genuchten, Case M; Dutta, Amit; DebSarkar, Anupam; Orr, Christopher; Roy, Joyashree; Das, Abhijit; Gadgil, Ashok J
2014-08-01
Millions of people in rural South Asia are exposed to high levels of arsenic through groundwater used for drinking. Many deployed arsenic remediation technologies quickly fail because they are not maintained, repaired, accepted, or affordable. It is therefore imperative that arsenic remediation technologies be evaluated for their ability to perform within a sustainable and scalable business model that addresses these challenges. We present field trial results of a 600 L Electro-Chemical Arsenic Remediation (ECAR) reactor operating over 3.5 months in West Bengal. These results are evaluated through the lens of a community scale micro-utility business model as a potential sustainable and scalable safe water solution for rural communities in South Asia. We demonstrate ECAR's ability to consistently reduce arsenic concentrations of ~266 μg/L to <5 μg/L in real groundwater, simultaneously meeting the international standards for iron and aluminum in drinking water. ECAR operating costs (amortized capital plus consumables) are estimated as $0.83-$1.04/m(3) under realistic conditions. We discuss the implications of these results against the constraints of a sustainable and scalable business model to argue that ECAR is a promising technology to help provide a clean water solution in arsenic-affected areas of South Asia. Copyright © 2013 Elsevier B.V. All rights reserved.
Argonne National Laboratory-East site environmental report for calendar year 1998.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Golchert, N.W.; Kolzow, R.G.
1999-08-26
This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL-E) for 1998. To evaluate the effects of ANL-E operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL-E site were analyzed and compared with applicable guidelines and standards. A variety of radionuclides were measured in air, surface water, on-site groundwater, and bottom sediment samples. In addition, chemical constituents in surface water, groundwater, and ANL-E effluent water were analyzed. External penetrating radiation doses were measured, and the potential for radiation exposure to off-site population groups wasmore » estimated. Results are interpreted in terms of the origin of the radioactive and chemical substances (i.e., natural, fallout, ANL-E, and other) and are compared with applicable environmental quality standards. A US Department of Energy dose calculation methodology, based on International Commission on Radiological Protection recommendations and the US Environmental Protection Agency's CAP-88 (Clean Air Act Assessment Package-1988) computer code, was used in preparing this report. The status of ANL-E environmental protection activities with respect to the various laws and regulations that govern waste handling and disposal is discussed, along with the progress of environmental corrective actions and restoration projects.« less
1999-04-06
Key participants in the signing of a Memorandum of Agreement, formalizing cooperative efforts of NASA, the U.S. Air Force, and federal agencies in ground-water cleanup initiatives, gather on top of the block house at Launch Complex 34. Motioning at right is Skip Chamberlain, program manager, Office of Science and Technology, U.S. Department of Energy. Others on the tour include Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; Roy Bridges Jr., director of John F. Kennedy Space Center; Walter Kovalick Jr., Ph.D., director, Technology Innovation Office, U.S. Environmental Protection Agency. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally
1999-04-06
Walter W. Kovalick Jr., Ph.D., director of Technology Innovation Office for the U.S. Environmental Protection Agency, addresses representatives from Kennedy Space Center, the 45th Space Wing, and various federal environmental agencies gathered to attend a Memorandum of Agreement (MOA) signing, taking place at the site of Launch Complex 34. The MOA formalizes the cooperative efforts of the federal agencies in ground-water cleanup initiatives. NASA, the U.S. Air Force and the agencies have formed a consortium and are participating in a comparative study of three innovative techniques to be used in cleaning a contaminated area of Launch Complex 34. The study will be used to help improve groundwater cleanup processes nationally. Other attendees included Timothy Oppelt, director, National Risk Management Research Laboratory, U.S. Environmental Protection Agency; Tom Heenan, assistant manager of environmental management, Savannah River Site, U.S. Department of Energy; Col. James Heald, Vice Commander, Air Force Research Laboratory, U.S. Air Force; Gerald Boyd, acting deputy assistant secretary, Office of Science and Technology, U.S. Department of Energy; James Fiore, acting deputy assistant secretary, Office of Environmental Restoration, Department of Energy; Brig. Gen. Randall R. Starbuck, Commander 45th Space Wing, U.S. Air Force; and Roy Bridges Jr., director of John F. Kennedy Space Center
Monitoring Anaerobic TCE Degradation by Evanite Cultre in Column Packed with TCE-Contaminated Soil
NASA Astrophysics Data System (ADS)
Ko, J.; Han, K.; Ahn, G.; Park, S.; Kim, N.; Ahn, H.; Kim, Y.
2011-12-01
Trichloroethylene (TCE) is a long-term common groundwater pollutant because the compound with high density is slowly released into groundwater. Physical and chemical remediation processes have been used to clean-up the contaminant, but novel remediation technology is required to overcome a low efficiency of the traditional treatment process. Many researchers focused on biological process using an anaerobic TCE degrading culture, dehalococcoides spp., but it still needs to evaluate whether the process can be applied into field scale under aerobic condition. Therefore, in this work we examined two different types (i.e., Natural attenuation and bioaugmentation) of biological remediation process in anaerobic column packed with TCE-contaminated soil. A TCE degradation by indigenous microorganisms was confirmed by monitoring TCE and the metabolites (c-DCE, VC, ETH). However, TCE was transformed and stoichiometry amount of c-DCE was produced, and VC and ETH was not detected. To test bioaugmentation of Evanite culture containing dehalococcoides spp., Evanite culture was injected into the column and TCE degradation to c-DCE, VC, ETH was monitored. We are evaluating the transport of the Evanite culture in the column by measuring TCE and VC reductases. In the result, the TCE was completely degraded to ETH using hydrogen as electron donor generate by hydrogen-production fermentation from formate.
Long-Term Oil Pollution and In Situ Microbial Response of Groundwater in Northwest China.
Sun, Yujiao; Lu, Sidan; Zhao, Xiaohui; Ding, Aizhong; Wang, Lei
2017-05-01
Potential threats exist where groundwater is polluted by high concentrations of oil compounds (980.20 mg L -1 the highest TPHs). An abandoned petrochemical plant in Lanzhou City, where long-term petrochemical products leakage contaminated the groundwater, was used as a field site in this study. To determine the extent of pollution and find an effective solution, chemical techniques combined with molecular biological techniques were used to survey the migration and decomposition of pollutants. Moreover, Illumina Sequencing was employed to reveal the microbial changes of different sites. Light-chain alkanes (mostly C6-C9), most benzene compounds, and some polycyclic aromatic hydrocarbons (naphthalene, 2-methylnaphthalene) mainly polluted the source. C29 to C36 and chlorobenzenes (hexachlorocyclohexane) polluted the secondary polluted sites. Moreover, chloralkane (trichloroethane and dichloroethane), benzene derivatives (trimethylbenzene and butylbenzene), and PAHs (fluorene and phenanthrene) were present in the other longtime-contaminated water. The bacterial genera are closely related with the chemical matters, and different groups of microorganisms gather in the sample sites that are polluted with different kinds of oil. The biodiversity and abundance of observed species change with pollution conditions. The dominant phyla (81%) of the bacterial community structure are Proteobacteria (62.2% of the total microbes), Bacteroidetes (8.85%), Actinobacteria (6.70%), and Choloroflexi (3.03%). Pseudomonadaceae is significant in the oil-polluted source and Comamonadaceae is significant in the secondary polluted (migrated oil) sample; these two genera are natural decomposers of refractory matters. Amycolatopsis, Rhodocyclaceae, Sulfurimonas, and Sulfuricurvum are the dominant genera in the long-migrated oil-polluted samples. Bioavailability of the oil-contaminated place differs with levels of pollution and cleaning the worse-polluted sites by microbes is more difficult.
Colonie Interim Storage Site annual environmental report for calendar year 1991, Colonie, New York
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-09-01
This document describes the environmental monitoring program at the Colonie Interim Storage Site (CISS) and surrounding area, implementation of the program, and monitoring results for 1991. Environmental monitoring at CISS began in 1984 when Congress added the site to the US Department of Energy's Formerly Utilized Sites Remedial Action Program. CISS property and surrounding areas were radioactively contaminated by operations conducted by National Lead Industries, which manufactured various components from uranium and thorium from 1958 to 1984. The environmental monitoring program at CISS includes sampling networks for external gamma radiation exposure and for radium-226, thorium-232, and total uranium concentrations inmore » surface water, sediment, and groundwater. Additionally, several nonradiological parameters are measured in groundwater. In 1992 the program will also include sampling networks for radioactive and chemical contaminants in stormwater to meet permit application requirements under the Clean Water Act. Monitoring results are compared with applicable Environmental Protection Agency (EPA) standards, DOE derived concentration guides (DCGs), dose limits, and other requirements in DOE.orders. Environmental standards are established to protect public health and the environment. Results of environmental monitoring during 1991 indicate that average concentrations of radioactive contaminants of concern were well below applicable standards and DCGS. Concentrations of some chemical contaminants in groundwater were above-the New York State Department of Environmental Conservation (Class GA) and EPA guidelines for drinking water. The potential annual radiation exposure (excluding background) calculated for a hypothetical maximally exposed individual is 0.23 mrem (milliroentgen equivalent man), which is less than an individual would receive while traveling in an airplane at 12,000 meters (39,000 feet) for one hour.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-09-01
This document describes the environmental monitoring program at the Colonie Interim Storage Site (CISS) and surrounding area, implementation of the program, and monitoring results for 1991. Environmental monitoring at CISS began in 1984 when Congress added the site to the US Department of Energy`s Formerly Utilized Sites Remedial Action Program. CISS property and surrounding areas were radioactively contaminated by operations conducted by National Lead Industries, which manufactured various components from uranium and thorium from 1958 to 1984. The environmental monitoring program at CISS includes sampling networks for external gamma radiation exposure and for radium-226, thorium-232, and total uranium concentrations inmore » surface water, sediment, and groundwater. Additionally, several nonradiological parameters are measured in groundwater. In 1992 the program will also include sampling networks for radioactive and chemical contaminants in stormwater to meet permit application requirements under the Clean Water Act. Monitoring results are compared with applicable Environmental Protection Agency (EPA) standards, DOE derived concentration guides (DCGs), dose limits, and other requirements in DOE.orders. Environmental standards are established to protect public health and the environment. Results of environmental monitoring during 1991 indicate that average concentrations of radioactive contaminants of concern were well below applicable standards and DCGS. Concentrations of some chemical contaminants in groundwater were above-the New York State Department of Environmental Conservation (Class GA) and EPA guidelines for drinking water. The potential annual radiation exposure (excluding background) calculated for a hypothetical maximally exposed individual is 0.23 mrem (milliroentgen equivalent man), which is less than an individual would receive while traveling in an airplane at 12,000 meters (39,000 feet) for one hour.« less
van Genuchten, Case M; Bandaru, Siva R S; Surorova, Elena; Amrose, Susan E; Gadgil, Ashok J; Peña, Jasquelin
2016-06-01
Extended field trials to remove arsenic (As) via Fe(0) electrocoagulation (EC) have demonstrated consistent As removal from groundwater to concentrations below 10 μg L(-1). However, the coulombic performance of long-term EC field operation is lower than that of laboratory-based systems. Although EC electrodes used over prolonged periods show distinct passivation layers, which have been linked to decreased treatment efficiency, the spatial distribution and mineralogy of such surface layers have not been investigated. In this work, we combine wet chemical measurements with sub-micron-scale chemical maps and selected area electron diffraction (SAED) to determine the chemical composition and mineral phase of surface layers formed during long-term Fe(0) EC treatment. We analyzed Fe(0) EC electrodes used for 3.5 months of daily treatment of As-contaminated groundwater in rural West Bengal, India. We found that the several mm thick layer that formed on cathodes and anodes consisted of primarily magnetite, with minor fractions of goethite. Spatially-resolved SAED patterns also revealed small quantities of CaCO3, Mn oxides, and SiO2, the source of which was the groundwater electrolyte. We propose that the formation of the surface layer contributes to decreased treatment performance by preventing the migration of EC-generated Fe(II) to the bulk electrolyte, where As removal occurs. The trapped Fe(II) subsequently increases the surface layer size at the expense of treatment efficiency. Based on these findings, we discuss several simple and affordable methods to prevent the efficiency loss due to the surface layer, including alternating polarity cycles and cleaning the Fe(0) surface mechanically or via electrolyte scouring. Copyright © 2016 Elsevier Ltd. All rights reserved.
Paraelectric gas flow accelerator
NASA Technical Reports Server (NTRS)
Sherman, Daniel M. (Inventor); Wilkinson, Stephen P. (Inventor); Roth, J. Reece (Inventor)
2001-01-01
A substrate is configured with first and second sets of electrodes, where the second set of electrodes is positioned asymmetrically between the first set of electrodes. When a RF voltage is applied to the electrodes sufficient to generate a discharge plasma (e.g., a one-atmosphere uniform glow discharge plasma) in the gas adjacent to the substrate, the asymmetry in the electrode configuration results in force being applied to the active species in the plasma and in turn to the neutral background gas. Depending on the relative orientation of the electrodes to the gas, the present invention can be used to accelerate or decelerate the gas. The present invention has many potential applications, including increasing or decreasing aerodynamic drag or turbulence, and controlling the flow of active and/or neutral species for such uses as flow separation, altering heat flow, plasma cleaning, sterilization, deposition, etching, or alteration in wettability, printability, and/or adhesion.
The Sun-Earth saddle point: characterization and opportunities to test general relativity
NASA Astrophysics Data System (ADS)
Topputo, Francesco; Dei Tos, Diogene A.; Rasotto, Mirco; Nakamiya, Masaki
2018-04-01
The saddle points are locations where the net gravitational accelerations balance. These regions are gathering more attention within the astrophysics community. Regions about the saddle points present clean, close-to-zero background acceleration environments where possible deviations from General Relativity can be tested and quantified. Their location suggests that flying through a saddle point can be accomplished by leveraging highly nonlinear orbits. In this paper, the geometrical and dynamical properties of the Sun-Earth saddle point are characterized. A systematic approach is devised to find ballistic orbits that experience one or multiple passages through this point. A parametric analysis is performed to consider spacecraft initially on L_{1,2} Lagrange point orbits. Sun-Earth saddle point ballistic fly-through trajectories are evaluated and classified for potential use. Results indicate an abundance of short-duration, regular solutions with a variety of characteristics.
NASA Technical Reports Server (NTRS)
Moore, J. A.
1976-01-01
Results from an experimental study of the opening characteristics of an electromagnetically opened, 15.24 cm diameter diaphragm are presented. This diaphragm consists of a polyester film bonded to a preformed wire and is opened by passing a current pulse (capacitor discharge) through the wire. The diaphragm separates the acceleration section of the expansion tunnel from the nozzle so that the nozzle may be at a lower pressure than the acceleration section prior to a test. Opening times and cleanness of the opened area were examined for dependence on diaphragm thickness, on wire diameter, on technique of bonding the wire to the diaphragm, and on voltage and energy level of the energy source. Time histories of the pitot pressure measured at the expansion-tunnel nozzle entrance location are presented for (1) no diaphragm, (2) a flow-opened diaphragm, and (3) an electromagnetically opened diaphragm.
Parikh, Alpa; van de Rijn, Jennifer; Melville, Chris; Sarkari, Marazban; Peltier, Sylvie; McKean, Robert
2018-04-01
Purpose Omacetaxine mepesuccinate ("omacetaxine") is approved by the US Food and Drug Administration for the treatment of adult patients with chronic- or accelerated-phase chronic myeloid leukemia with resistance and/or intolerance to two or more tyrosine kinase inhibitors. In May 2014, the US Food and Drug Administration approved revisions to the packaging information that included directions for home administration of reconstituted omacetaxine by patients or caregivers using syringes filled at a healthcare facility. We developed recommendations for the transport, storage, and spill-clean procedure of reconstituted omacetaxine for home and clinic administration. Methods We conducted chemical stability and microbial growth studies of reconstituted omacetaxine solution stored in vials and syringes at room temperature or refrigerated for various durations. Several shipping configurations were tested in simulated transport conditions to evaluate their ability to contain solution leakage and maintain product quality during distribution. In addition, we evaluated cleaning products and procedures for their effectiveness in removing residual omacetaxine from household surfaces after mock spills. Results Reconstituted omacetaxine showed limited degradation when refrigerated for 14 days in vials and syringes, and no microbial growth was observed for 12 days after intentional inoculation. In shipping studies, the configurations maintained prepared syringes within the recommended storage temperature range throughout transport and could contain leaks if spills occurred. In the event of an accidental spill in a home environment, effective cleaning can be achieved using household cleaning products and defined procedures. Conclusion These data provide important information regarding the safe transportation and administration of reconstituted omacetaxine in the home and clinic.
Piezo-based motion stages for heavy duty operation in clean environments
NASA Astrophysics Data System (ADS)
Karasikov, Nir; Peled, Gal; Yasinov, Roman; Gissin, Michael; Feinstein, Alan
2018-02-01
A range of heavy duty, ultra-precise motion stages had been developed for precise positioning in semiconductor manufacturing and metrology, for use in a clean room and high vacuum (HV and UHV) environments, to meet the precision requirements for 7, 5 nm nodes and beyond. These stages are powered by L1B2 direct drive ultrasonic motors, which allows combining long motion range, sub-nanometer positioning accuracy, high stiffness (in the direction of motion), low power consumption and active compensation of thermal and structural drift while holding position. The mechanical design, material selection for clean room and high vacuum preparation techniques are reviewed. Test results in a clean room are reported for a two-axis (X-Y) stage, having a load capacity of 30 kg, a motion range of 450 mm, a positioning accuracy of < 1 nm, a maximum motion speed of > 200 mm/s and a < 2 nm position stability (3 sigma). Long term drift compensation to sub-nm level, against thermal drift, has been validated for more than 10 hours. Heavy duty operation in a high vacuum is exemplified via a single axis stage operating at 5E-7 Torr, having a moving mass of 0.96 kg, oriented against gravity. The stage is operated periodically (up and down) over a travel length of 45 mm. The motion profile has a trapezoidal shape with an acceleration of 1m/s2 and a constant velocity of 100 mm/s. The operational parameters (average absolute position error during constant velocity, motor force, dead zone level) remain stable over more than 370000 passes (experiment duration).
Gaining Regulator Acceptance of Natural Attenuation as a Remediation Tool
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hughes, M.B.
Monitored natural attenuation (MNA) makes use of biological degradation, chemical reactions with natural materials, and other processes to clean up contaminated soils and groundwater. In the past, the regulatory community has been slow to accept natural attenuation due to a misperception that natural attenuation is a ''do nothing'' approach. Recently however, regulators have been more open to considering MNA as part of an overall clean-up plan that includes active treatment technologies to remove or contain the source of contamination at a site. MNA is currently being implemented at the Savannah River Site for remediation of selected contaminants. The South Carolinamore » Department of Health and Environmental Control, who has regulatory authority over these actions, has accepted this process. Significant overall cost savings are forecast. Additionally, there will be less disruption to the ecosystem, compared with engineered technologies. This paper describes the monitored natural attenuation concept as well as the process of constructive engagement with the regulators to achieve acceptance. Application to DOE, DOD, and commercial sites, as well as acceptability to other regulatory bodies, will be discussed with an emphasis on strategies to prevent false starts in the negotiation process and inventing options that result in mutual gains for all parties.« less
Prevention and management of silica scaling in membrane distillation using pH adjustment
Bush, John A.; Vanneste, Johan; Gustafson, Emily M.; ...
2018-02-27
Membrane scaling by silica is a major challenge in desalination, particularly for inland desalination of brackish groundwater or geothermal resources, which often contain high concentrations of silica and dissolved solids. Adjustment of feed pH may reduce silica scaling risk, which is important for inland facilities that operate at high water recoveries to reduce brine disposal costs. However, water recovery of reverse osmosis is also limited due to increased osmotic pressure with feed water concentration. Membrane distillation (MD) is a thermally driven membrane desalination technique that is not limited by increased osmotic pressure of the feed. In this investigation, pH adjustmentmore » was tested as a strategy to reduce silica scaling risk in the MD process. With feed water pH less than 5 or higher than 10, scaling impacts were negligible at silica concentrations up to 600 mg/L. Scaling rates were highest at neutral pH between 6 and 8. Cleaning strategies were also explored to remove silica scale from membranes. Cleaning using NaOH solutions at pH higher than 11 to induce dissolution of silica scale was effective at temporarily restoring performance; however, some silica remained on membrane surfaces and scaling upon re-exposure to supersaturated silica concentrations occurred faster than with new membranes.« less
Using stable isotopes to examine watershed connectivity to ...
Water bodies within the USA are protected by the US Clean Water Act when they have a significant nexus to downstream navigable waters. As a research scientist with the US Environmental Protection Agency, I have used water stable isotopes to examine hydrologic connectivity dynamics. I will share two case studies. In the first case, we used the isotopic evaporation signal in water to examine wetland-stream hydrologic connectivity within the Pipestem Creek watershed, North Dakota, a watershed dominated by prairie-pothole wetlands. Prairie-Pothole wetlands are a special case of wetlands whose protection needs to be determined under the Clean Water Rule. Pipestem Creek exhibited an evaporated-water signal that had approximately half the isotopic-enrichment signal found in most evaporatively enriched prairie-pothole wetlands. Groundwater measured at the water table adjacent to Pipestem Creek had isotopic values that indicated recharge from winter precipitation and had no significant evaporative enrichment. Using isotopic theory and discharge data, we estimated the area of surface water necessary to generate the evaporation signal found within Pipestem Creek over two years. Our results indicated that prairie-pothole wetlands were important sources of stream flow in Pipestem Creek throughout the summer, as well as during snowmelt. They also demonstrated that at the lowest flows, the stream itself became disconnected from headwater stream reaches. In the second ca
NASA Astrophysics Data System (ADS)
Hinić, V.; Rubinić, J.; Vučković, I.; Ružić, I.; Gržetić, A.; Volf, G.; Ljubotina, M.; Kvas, N.
2008-11-01
Sinking watercourse Trbuhovica is located at the topping karst of Gorski Kotar in Croatia, near the Slovenian border. About 900 inhabitants live in Trbuhovica catchment area. Sewage system had not been built. The project KEEP WATERS CLEAN (INTERREG III A project) was approved by EU commission and has a purpose of investigating water resources of that area, their appropriate protection and improving management of those resources. This paper presents project's 1st phase investigation results: hydrologic conditions and water quality at several locations on stream and at the springs of Trbuhovica, Mlake and Obrh. Climatologic (precipitation, air temperature and snow cover), basic hydrologic characteristics (flow and water temperature), water quality parameters (pH, electric conductivity, alkalinity, oxygen regime, nutrients and mineral oils) and microbiology indicators have been monitored. Samples of micro invertebrates and samples of periphyton have been collected in the field. Biological results have been elaborated via Saprobial Index according to Pantle-Buck. Analyses results showed a strong connection between hydrologic condition and selected water quality parameters. The groundwater quality changes are very quick. Maximum pollutions occur during the period of intensive rain. Water at the spring of Mlaka is very clean and is classified in the first to second water category, while Trbuhovica shows higher organic pollution.
Prevention and management of silica scaling in membrane distillation using pH adjustment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bush, John A.; Vanneste, Johan; Gustafson, Emily M.
Membrane scaling by silica is a major challenge in desalination, particularly for inland desalination of brackish groundwater or geothermal resources, which often contain high concentrations of silica and dissolved solids. Adjustment of feed pH may reduce silica scaling risk, which is important for inland facilities that operate at high water recoveries to reduce brine disposal costs. However, water recovery of reverse osmosis is also limited due to increased osmotic pressure with feed water concentration. Membrane distillation (MD) is a thermally driven membrane desalination technique that is not limited by increased osmotic pressure of the feed. In this investigation, pH adjustmentmore » was tested as a strategy to reduce silica scaling risk in the MD process. With feed water pH less than 5 or higher than 10, scaling impacts were negligible at silica concentrations up to 600 mg/L. Scaling rates were highest at neutral pH between 6 and 8. Cleaning strategies were also explored to remove silica scale from membranes. Cleaning using NaOH solutions at pH higher than 11 to induce dissolution of silica scale was effective at temporarily restoring performance; however, some silica remained on membrane surfaces and scaling upon re-exposure to supersaturated silica concentrations occurred faster than with new membranes.« less
2000-01-25
At Launch Complex 34, representatives from environmental and Federal agencies head for the block house during presentations about the environmental research project that involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA in a groundwater cleanup effort. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program, which used the complex, in the 60s. The group formed the Interagency NDAPL Consortium (IDC) to study three contamination cleanup technologies: Six Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. KSC hosted a two-day conference that presented information and demonstrations of the three technologies being tested at the site
2000-01-25
At Launch Complex 34, Greg Beyke, with Current Environmental Solutions, talks to representatives from environmental and federal agencies about the environmental research project that involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA in a groundwater cleanup effort. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program, which used the complex, in the 60s. The group formed the Interagency NDAPL Consortium (IDC) to study three contamination cleanup technologies: Six Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. KSC hosted a two-day conference that presented information and demonstrations of the three technologies being tested at the site
2000-01-25
At Launch Complex 34, Greg Beyke, with Current Environmental Solutions, talks to representatives from environmental and federal agencies about the environmental research project that involves the Department of Defense, Environmental Protection Agency, Department of Energy and NASA in a groundwater cleanup effort. Concentrations of trichloroethylene solvent have been identified in the soil at the complex as a result of cleaning methods for rocket parts during the Apollo Program, which used the complex, in the 60s. The group formed the Interagency NDAPL Consortium (IDC) to study three contamination cleanup technologies: Six Phase Soil Heating, Steam Injection and In Situ Oxidation with Potassium Permanganate. All three methods may offer a way to remove the contaminants in months instead of decades. KSC hosted a two-day conference that presented information and demonstrations of the three technologies being tested at the site