Science.gov

Sample records for subsurface drainage systems

  1. An analytical solution for predicting the transient seepage from a subsurface drainage system

    NASA Astrophysics Data System (ADS)

    Xin, Pei; Dan, Han-Cheng; Zhou, Tingzhang; Lu, Chunhui; Kong, Jun; Li, Ling

    2016-05-01

    Subsurface drainage systems have been widely used to deal with soil salinization and waterlogging problems around the world. In this paper, a mathematical model was introduced to quantify the transient behavior of the groundwater table and the seepage from a subsurface drainage system. Based on the assumption of a hydrostatic pressure distribution, the model considered the pore-water flow in both the phreatic and vadose soil zones. An approximate analytical solution for the model was derived to quantify the drainage of soils which were initially water-saturated. The analytical solution was validated against laboratory experiments and a 2-D Richards equation-based model, and found to predict well the transient water seepage from the subsurface drainage system. A saturated flow-based model was also tested and found to over-predict the time required for drainage and the total water seepage by nearly one order of magnitude, in comparison with the experimental results and the present analytical solution. During drainage, a vadose zone with a significant water storage capacity developed above the phreatic surface. A considerable amount of water still remained in the vadose zone at the steady state with the water table situated at the drain bottom. Sensitivity analyses demonstrated that effects of the vadose zone were intensified with an increased thickness of capillary fringe, capillary rise and/or burying depth of drains, in terms of the required drainage time and total water seepage. The analytical solution provides guidance for assessing the capillary effects on the effectiveness and efficiency of subsurface drainage systems for combating soil salinization and waterlogging problems.

  2. Effects of macro-pores on water flow in coastal subsurface drainage systems

    NASA Astrophysics Data System (ADS)

    Xin, Pei; Yu, Xiayang; Lu, Chunhui; Li, Ling

    2016-01-01

    Leaching through subsurface drainage systems has been widely adopted to ameliorate saline soils. The application of this method to remove salt from reclaimed lands in the coastal zone, however, may be impacted by macro-pores such as crab burrows, which are commonly distributed in the soils. We developed a three-dimensional model to investigate water flow in subsurface drainage systems affected by macro-pores distributed deterministically and randomly through Monte Carlo simulations. The results showed that, for subsurface drainage systems under the condition of continuous surface ponding, macro-pores increased the hydraulic head in the deep soil, which in turn reduced the hydraulic gradient between the surface and deep soil. As a consequence, water infiltration across the soil surface was inhibited. Since salt transport in the soil is dominated by advection, the flow simulation results indicated that macro-pores decreased the efficiency of salt leaching by one order of magnitude, in terms of both the elapsed time and the amount of water required to remove salt over the designed soil leaching depth (0.6 m). The reduction of the leaching efficiency was even greater in drainage systems with a layered soil stratigraphy. Sensitivity analyses demonstrated that with an increased penetration depth or density of macro-pores, the leaching efficiency decreased further. The revealed impact of macro-pores on water flow represents a significant shortcoming of the salt leaching technique when applied to coastal saline soils. Future designs of soil amelioration schemes in the coastal zone should consider and aim to minimize the bypassing effect caused by macro-pores.

  3. Subsurface Drainage Nitrate and Total Reactive Phosphorus Losses in Bioenergy-Based Prairies and Corn Systems.

    PubMed

    Daigh, Aaron L M; Zhou, Xiaobo; Helmers, Matthew J; Pederson, Carl H; Horton, Robert; Jarchow, Meghann; Liebman, Matt

    2015-09-01

    We compare subsurface-drainage NO-N and total reactive phosphorus (TRP) concentrations and yields of select bioenergy cropping systems and their rotational phases. Cropping systems evaluated were grain-harvested corn-soybean rotations, grain- and stover-harvested continuous corn systems with and without a cover crop, and annually harvested reconstructed prairies with and without the addition of N fertilizer in an Iowa field. Drainage was monitored when soils were unfrozen during 2010 through 2013. The corn-soybean rotations without residue removal and continuous corn with residue removal produced similar mean annual flow-weighted NO-N concentrations, ranging from 6 to 18.5 mg N L during the 4-yr study. In contrast, continuous corn with residue removal and with a cover crop had significantly lower NO-N concentrations of 5.6 mg N L when mean annual flow-weighted values were averaged across the 4 yr. Prairies systems with or without N fertilization produced significantly lower concentrations below <1 mg NO-N L than all the row crop systems throughout the study. Mean annual flow-weighted TRP concentrations and annual yields were generally low, with values <0.04 mg TRP L and <0.14 kg TRP ha, and were not significantly affected by any cropping systems or their rotational phases. Bioenergy-based prairies with or without N fertilization and continuous corn with stover removal and a cover crop have the potential to supply bioenergy feedstocks while minimizing NO-N losses to drainage waters. However, subsurface drainage TRP concentrations and yields in bioenergy systems will need further evaluation in areas prone to higher levels of P losses.

  4. Subsurface irrigation of potato crop (Solanum tuberosum ssp. Andigena) in Suka Kollus with different drainage systems

    NASA Astrophysics Data System (ADS)

    Serrano-Coronel, Genaro; Chipana-Rivera, René; Fátima Moreno-Pérez, María; Roldán-Cañas, José

    2016-04-01

    Among the most important hydraulic structures of pre-Hispanic ancestral technology developed in the Andean region, we find the suka kollus, aymara word, called also waru waru, en quechua or raised fields, in English. They are raised platforms surrounded by water canals that irrigate subsurface, but also have the function of draining, to deal with floods because they are surrounding Lake Titicaca. They also have the property of generating a thermoregulatory effect to crops, depending on the configuration of the channels and platforms. Such agro-ecosystems are being abandoned, however, if properly addressed crop management and some drainage canals are replaced by underground drains for increased crop area could be very useful in enabling marginal soils affected by salts and / or excess water. For these reasons, the objective of this study was to evaluate the subsurface irrigation in the potato crop in suka kollus under a system of surface drainage, and mixed drainage (surface and subsurface). The study was conducted in marginal soils of Kallutaca area, located 30 km from the city of La Paz, Bolivia, at a height of 3892 m.a.s.l. The cultivation of the potato (Solanum tuberosum ssp. Andigena) was used. Four treatments were tested with different widths of the platforms: T1 (Control) with drainage through channels; T2 (replacing a channel by a drain); T3 (replacing two channels by two drains); T4 (replacing three channels by three drains). The flow of water into the soil from the water table was predominantly upward, except during periods of high rainfall. In terms of treatments, the flow in T1 was higher, mainly at weeks 8 to 11 after seedling emergence, coinciding with the phenological phases of flowering and at the beginning of the tuber ripening. It was followed by T3, T2 and T4 treatments, respectively. Tuber yield, if one considers that the channels detract arable land, was higher in the T3 treatment,16.4 Mg / ha, followed by T2 treatment, 15.2 Mg / ha, T1

  5. Research and Development of Laser-Beam Automatic Grade-Control System on High-Speed Subsurface Drainage Equipment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface drainage methods and materials technologies were modernized more through innovative research and development between 1960 and 1975 than during the previous 100 years. By the mid-1970’s, slow, inefficient trench-installation of heavy rigid draintile materials (clay and concrete) gave way t...

  6. Subsurface recharge to the Tesuque aquifer system from selected drainage basins along the western side of the Sangre de Cristo Mountains near Santa Fe, New Mexico

    USGS Publications Warehouse

    Wasiolek, Maryann

    1995-01-01

    Water budgets developed for basins of five streams draining the western side of the Sangre de Cristo Mountains in northern New Mexico indicate that subsurface inflow along the mountain front is recharging the Tesuque aquifer system of the Espanola Basin. Approximately 14,700 acre-feet of water per year, or 12.7 percent of average annual precipitation over the mountains, is calculated to leave the mountain block and enter the basin as subsurface recharge from the drainage basins of the Rio Nambe, Rio en Medio, Tesuque Creek, Little Tesuque Creek, and Santa Fe River. About 5,520 acre- feet per year, or about 12 percent of average annual precipitation, is calculated to enter from the Rio Nambe drainage basin; about 1,710 acre- feet per year, or about 15 percent of average annual precipitation, is calculated to enter from the Rio en Medio drainage basin; about 1,530 acre- feet, or about 10 percent of average annual precipi- tation, is calculated to enter from the Tesuque Creek drainage basin; about 1,790 acre-feet, or about 19 percent of average annual precipitation, is calculated to enter from the Little Tesuque Creek drainage basin; and about 4,170 acre-feet per year, or about 12 percent average annual precipitation, is calculated to enter from the Santa Fe River drainage basin. Calculated subsurface recharge values were used to define maximum fluxes permitted along the specified-flux boundary defining the mountain front of the Sangre De Cristo Mountains in a numerical computer model of the Tesuque aquifer system near Santa Fe, New Mexico.

  7. Subsurface agricultural irrigation drainage: the need for regulation.

    PubMed

    Lemly, A D

    1993-04-01

    Subsurface drainage resulting from irrigated agriculture is a toxic threat to fish and wildlife resources throughout the western United States. Studies by the U.S. Department of the Interior show that migratory waterfowl have been poisoned by drainwater contaminants on at least six national wildlife refuges. Allowing this poisoning to continue is a violation of the Migratory Bird Treaty Act under U.S. Federal law. Critical wetlands and waterfowl populations are threatened in both the Pacific and Central flyways. The public is also at risk and health warnings have been issued in some locations. Subsurface irrigation drainage is a complex effluent containing toxic concentrations of trace elements, salts, and nitrogenous compounds. Some of the contaminants are classified by the U.S. Environmental Protection Agency (EPA) as priority pollutants and they can be present in concentrations that exceed EPA's criteria for toxic waste. The on-farm drainage systems used to collect and transport this wastewater provide point-source identification as well as a mechanism for toxics control through the National Pollutant Discharge Elimination System (NPDES) permit process. A four-step approach is presented for dealing with irrigation drainage in an environmentally sound manner. This regulatory strategy is very similar to those commonly used for industrial discharges and includes site evaluation, contaminant reduction through NPDES, and compliance monitoring. The EPA must recognize subsurface irrigation drainage as a specific class of pollution subject to regulation under the NPDES process. Active involvement by EPA is necessary to ensure that adequate controls on this wastewater are implemented.

  8. Hydrologic Impact Of Subsurface Drainage Of Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Naz, B. S.; Johannsen, C. J.; Bowling, L. C.

    2005-12-01

    Although subsurface drainage has benefited agricultural productions in many regions of the U.S., there are also concerns about the potential impacts of these systems on watershed hydrology and water quality. This study was focused on tile lines identification and hydrologic response of subsurface drainage systems for the Agronomy Center for Research and Education (ACRE), West Lafayette, Indiana and the Southeastern Purdue Agriculture Center (SEPAC) in southeastern, Indiana. The purpose of the study was to develop and evaluate a remote sensing methodology for automatic detection of tile lines from aerial photographs and to evaluate the Distributed Hydrology Soil-Vegetation Model (DHSVM) to analyze the hydrologic response of tile drained fields. A step-wise approach was developed to first use different image enhancement techniques to increase the visual distinction of tile lines from other details in the image. A new classification model was developed to identify locations of subsurface tiles using a decision tree classifier which compares the multiple data sets such as enhanced image data, land use class, soil drainage class, hydrologic group and surface slope. Accuracy assessment of the predicted tile map was done by comparing the locations of tile drains with existing historic maps and ground-truth data. The overall performance of decision tree classifier model coupled with other pre- and post- classification methods shows that this model can be a very effective tool in identifying tile lines from aerial photographs over large areas of land. Once the tile map was created, the DHSVM was applied to ACRE and SEPAC respectively to see the hydrological impact of the subsurface drainage network. Observed data for 3-years (1998-2000) at ACRE and for 6-years (1993-1998) at SEPAC were used to calibrate and validate the model. The model was simulated for three scenarios: 1) baseline scenario (no tiles), 2) with known tile lines and 3) with tile lines created through

  9. Continuous Passive Sampling of Solutes from Agricultural Subsurface Drainage Tubes

    NASA Astrophysics Data System (ADS)

    Lindblad Vendelboe, Anders; de Jonge, Hubert; Rozemeijer, Joachim; Wollesen de Jonge, Lis

    2015-04-01

    Agricultural subsurface tube drain systems play an important role in water and solute transport. One study, focusing on lowland agricultural catchments, showed that subsurface tube drainage contributed up to 80% of the annual discharge and 90% of the annual NO3 load from agricultural fields to the receiving water bodies. Knowledge of e.g. nutrient loads and drainage volumes, based on measurements and modelling, are important for adequate water quality management. Despite the importance of tube drain transport of solutes, monitoring data are scarce. This scarcity is a result of the existing monitoring techniques for flow and contaminant load from tube drains being expensive and labor-extensive. The study presented here aimed at developing a cheap, simple, and robust method to monitor solute loads from tube drains. The method is based on the newly developed Flowcap, which can be attached to existing tube drain outlets and can measure total flow, contaminant load and flow-averaged concentrations of solutes in the drainage. The Flowcap builds on the existing Sorbicell principle, a passive sampling system that measures average concentrations over longer periods of time (days to months) for various compounds. The Sorbicell consists of two compartments permeable to water. One compartment contains an adsorbent and one contains a tracer. When water passes through the Sorbicell the compound of interest is absorbed while a tracer is released. Using the tracer loss to calculate the volume of water that has passed the Sorbicell it is possible to calculate the average concentration of the compound. When mounting Sorbicells in the Flowcap, a flow-proportional part of the drainage is sampled from the main stream. To accommodate the wide range of drainage flow rates two Flowcaps with different capacities were tested in the laboratory: one with a capacity of 25 L min-1 (Q25) and one with a capacity of 256 L min-1 (Q256). In addition, Sorbicells with two different hydraulic

  10. Comparison of the performances of DRAINMOD-NII and ADAPT models in simulating nitrate losses from subsurface drainage systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adequate knowledge on the movement of nitrate under different subsurface (tile) drain configurations and management practices in the U.S. Midwest, is essential for developing remedial measures for reducing hypoxic conditions in the Gulf of Mexico. In this study, DRAINMOD-NII, a daily time-step soil ...

  11. Mitigating nutrient leaching with a sub-surface drainage layer of granulated tires.

    PubMed

    Lisi, R D; Park, J K; Stier, J C

    2004-01-01

    Markets for scrap tires have expanded since the early 1990s with the development of value-added applications such as tire-derived fuel and crumb-rubber-amended asphalt. Granulated tires have also displayed the ability to adsorb volatile organic compounds, indicating that the rubber material can be a useful filter media. Sand-based root zones, typically used for golf course putting green and athletic field construction, lack sufficient cation exchange capacity to restrict nitrogen and phosphorus migration through the root zone and into sub-surface drainage systems. Therefore, the adsorptive properties of tire rubber for retaining nitrogen and phosphorus were studied when applied as a distinct sub-surface drainage or intermediate layer in golf course putting greens. A statistically significant reduction in the concentration of nitrate in leachate was achieved by replacing traditional pea gravel with equally sized granulated tires for the drainage layer media, although the mechanism of nitrate mitigation remains unclear. The results indicate that using granulated tires as a drainage layer or fill material beneath sand-based root zones does not compromise the function of the profile or quality of the vegetation while creating an environmentally beneficial and value-added option for scrap tire reuse.

  12. Effects of soil type upon metolachlor losses in subsurface drainage.

    PubMed

    Novak, S M; Portal, J M; Schiavon, M

    2001-01-01

    A field experiment at La Bouzule (Lorraine, France) investigated metolachlor movement to subsurface drains in two soil types, a silt loam and a heavy clay soil, under identical agricultural management practices and climatic conditions. Drainage volumes and concentrations of metolachlor in the soil plough layer and drainwater were monitored after herbicide application from May 1996 to February 1997, and from May to August 1998. Total losses in drainwater were 0.08% and 0.18% of the amount applied to the silt loam compared with 0.59% and 0.41% for the clay soil, in 1996/97 and 1998, respectively. In 1996/97, 32% of total metolachlor loss from the silt loam and 91% from the clay soil occurred during the spring/summer period following treatment. Peak concentrations were 18.5 and 171.6 microg l(-1) for the silt loam and 130.6 and 395.3 microg l(-1) for the clay soil during the spring/summer periods of 1996/97 and 1998, respectively. During the autumn/winter period, concentrations did not exceed 2.2 microg l(-1) for the silt loam and 2.6 microg l(-1) for the clay soil. The experimental results indicate that metolachlor losses in drainwater were primarily caused by preferential flow (macropore flow) which was greater in the clay soil than in the silt loam, and occurring mainly during the spring/summer periods.

  13. PASSIVE TREATMENT OF ACID ROCK DRAINAGE FROM A SUBSURFACE MINE

    EPA Science Inventory

    Acidic, metal-contaminated drainages are a critical problem facing many areas of the world. Acid rock drainage results when metal sulfide minerals, particularly pyrite, are oxidized by exposure to oxygen and water. The deleterious effects of these drainages on receiving streams a...

  14. Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

  15. Nitrate-nitrogen losses through subsurface drainage under various agricultural land covers.

    PubMed

    Qi, Zhiming; Helmers, Matthew J; Christianson, Reid D; Pederson, Carl H

    2011-01-01

    Nitrate-nitrogen (NO₃-N) loading to surface water bodies from subsurface drainage is an environmental concern in the midwestern United States. The objective of this study was to investigate the effect of various land covers on NO₃-N loss through subsurface drainage. Land-cover treatments included (i) conventional corn ( L.) (C) and soybean [ (L.) Merr.] (S); (ii) winter rye ( L.) cover crop before corn (rC) and before soybean (rS); (iii) kura clover ( M. Bieb.) as a living mulch for corn (kC); and (iv) perennial forage of orchardgrass ( L.) mixed with clovers (PF). In spring, total N uptake by aboveground biomass of rye in rC, rye in rS, kura clover in kC, and grasses in PF were 14.2, 31.8, 87.0, and 46.3 kg N ha, respectively. Effect of land covers on subsurface drainage was not significant. The NO₃-N loss was significantly lower for kC and PF than C and S treatments (p < 0.05); rye cover crop did not reduce NO₃-N loss, but NO₃-N concentration was significantly reduced in rC during March to June and in rS during July to November (p < 0.05). Moreover, the increase of soil NO₃-N from early to late spring in rS was significantly lower than the S treatment (p < 0.05). This study suggests that kC and PF are effective in reducing NO₃-N loss, but these systems could lead to concerns relative to grain yield loss and change in farming practices. Management strategies for kC need further study to achieve reasonable corn yield. The effectiveness of rye cover crop on NO-N loss reduction needs further investigation under conditions of different N rates, wider weather patterns, and fall tillage.

  16. Subsurface drainage volume reduction with drainage water management: Case studies in Ohio, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the main contributors to poor water quality in the Mississippi River and aeral increase in the hypoxic zone in the Gulf of Mexico is intensive drainage of the cropland within the watershed. Controlled drainage has been demonstrated as an approach to curb totla drainage outflow and nutrient di...

  17. Subsurface Drainage of Pavement Structures: Current Corps of Engineers and Industry Practice

    DTIC Science & Technology

    1991-12-01

    few decades. General material on drainage an emphasis on subsurface drainage. The topics dis- issues can be found in the work of Cedergren (1974, cussed...the sides of the United States. bottom of the pavement layers. The assumptions made Cedergren (1974) bases his infiltration estimates on about these...temperature, but also whetheror all water falling on the pavement area will infiltrate. I Alternatively. Cedergren (1974) assumes that bitu- The FHWA

  18. Phosphorus transport in agricultural subsurface drainage: A review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) loss from agricultural fields and watersheds has been an important water quality issue for decades because of the critical role P plays in eutrophication. Historically, most research focused on P losses by surface runoff and erosion because subsurface P losses were often deemed to be ...

  19. Detecting Subsurface Agricultural Tile Drainage using GIS and Remote Sensing Technique

    NASA Astrophysics Data System (ADS)

    Budhathoki, M.; Gokkaya, K.; Tank, J. L.; Christopher, S. F.; Hanrahan, B.

    2015-12-01

    Subsurface tile drainage is a common practice in many of the row crop dominated agricultural lands in the Upper Midwest, which increases yield by making the soil more productive. It is reported that nearly half of all cropland in Indiana benefits from some sort of artificial drainage. However, subsurface tile has a significant negative impact on surface water quality by providing a fast means of transport for nutrients from fertilizers. Therefore, generating spatial data of tile drainage in the field is important and useful for agricultural landscape and hydrological studies. Subsurface tile drains in Indiana's croplands are not widely mapped. In this study, we will delineate subsurface tile drainage in agricultural land in Shatto Ditch watershed, located in Kosciusko County, Indiana. We will use geo-spatial methodology, which was purposed by earlier researchers to detect tile drainage. We will use aerial color-infrared and satellite imagery along with Light Detection and Ranging (LiDAR) data. In order to map tile lines with possible accuracy, we will use GIS-based analysis in combination with remotely sensed data. This research will be comprised of three stages: 1) masking out the potential drainage area using a decision tree rule based on land cover information, soil drainage category, surface slope, and satellite image differencing technique, 2) delineate tile lines using image processing techniques, and 3) check the accuracy of mapped tile lines with ground control points. To our knowledge, this study will be the first to check the accuracy of mapping with ground truth data. Based on the accuracy of results, we will extend the methodology to greater spatial scales. The results are expected to contribute to better characterizing and controlling water pollution sources in Indiana, which is a major environmental problem.

  20. Relative importance of impervious area, drainage density, width function, and subsurface storm drainage on flood runoff from an urbanized catchment

    NASA Astrophysics Data System (ADS)

    Ogden, Fred L.; Raj Pradhan, Nawa; Downer, Charles W.; Zahner, Jon A.

    2011-12-01

    The literature contains contradictory conclusions regarding the relative effects of urbanization on peak flood flows due to increases in impervious area, drainage density and width function, and the addition of subsurface storm drains. We used data from an urbanized catchment, the 14.3 km2 Dead Run watershed near Baltimore, Maryland, USA, and the physics-based gridded surface/subsurface hydrologic analysis (GSSHA) model to examine the relative effect of each of these factors on flood peaks, runoff volumes, and runoff production efficiencies. GSSHA was used because the model explicitly includes the spatial variability of land-surface and hydrodynamic parameters, including subsurface storm drains. Results indicate that increases in drainage density, particularly increases in density from low values, produce significant increases in the flood peaks. For a fixed land-use and rainfall input, the flood magnitude approaches an upper limit regardless of the increase in the channel drainage density. Changes in imperviousness can have a significant effect on flood peaks for both moderately extreme and extreme storms. For an extreme rainfall event with a recurrence interval in excess of 100 years, imperviousness is relatively unimportant in terms of runoff efficiency and volume, but can affect the peak flow depending on rainfall rate. Changes to the width function affect flood peaks much more than runoff efficiency, primarily in the case of lower density drainage networks with less impermeable area. Storm drains increase flood peaks, but are overwhelmed during extreme rainfall events when they have a negligible effect. Runoff in urbanized watersheds with considerable impervious area shows a marked sensitivity to rainfall rate. This sensitivity explains some of the contradictory findings in the literature.

  1. Influence of alternative and conventional farming practices on subsurface drainage and water quality.

    PubMed

    Oquist, K A; Strock, J S; Mulla, D J

    2007-01-01

    Agricultural runoff contributes nutrients to nonpoint-source pollution of surface waters. This study was conducted to investigate the potential use of alternative farming practices to improve water quality. The study examined the effects of both alternative and conventional farming practices on subsurface drainage and nitrogen and phosphorus loss through subsurface drainage from glacial till soils (i.e., Calciaquolls, Endoaquolls, Eutrudepts, Hapludolls) in southwest Minnesota. Alternative farming practices included organic management practices, species biodiversity, and/or practices that include reduced inputs of synthetic fertilizer and pesticides. Conventional farming practices include corn-soybean (Zea mays L.-Glycine max L., respectively) rotations and their associated recommended fertilizer rates as well as pesticide usage. Precipitation was highly variable during the 3-yr study period including a below-average year (2003), an average year (2002), and an above-average year (2004). Results indicate that alternative farming practices reduced subsurface drainage discharge by 41% compared with conventional practices. Flow-weighted mean nitrate-nitrogen (nitrate N) concentrations during tile flow were 8.2 and 17.2 mg L(-1) under alternative and conventional farming practices, respectively. Alternative farming practices reduced nitrate N losses by between 59 and 62% in 2002 and 2004 compared with conventional practices. Ammonium-nitrogen (ammonium N), orthophosphorus, and total phosphorus losses in subsurface drainage were very low and did not pose a substantial risk of pollution. Results suggest that alternative farming practices have the potential to reduce agricultural impacts on water quality.

  2. Development, testing and application of DrainFlow: A fully distributed integrated surface-subsurface flow model for drainage study

    NASA Astrophysics Data System (ADS)

    Shokri, Ali; Bardsley, William Earl

    2016-06-01

    Hydrological and hydrogeological investigation of drained land is a complex and integrated procedure. The scale of drainage studies may vary from a high-resolution small scale project through to comprehensive catchment or regional scale investigations. This wide range of scales and integrated system behaviour poses a significant challenge for the development of suitable drainage models. Toward meeting these requirements, a fully distributed coupled surface-subsurface flow model titled DrainFlow has been developed and is described. DrainFlow includes both the diffusive wave equation for surface flow components (overland flow, open drain, tile drain) and Richard's equation for saturated/unsaturated zones. To overcome the non-linearity problem created from switching between wet and dry boundaries, a smooth transitioning technique is introduced to buffer the model at tile drains and at interfaces between surface and subsurface flow boundaries. This gives a continuous transition between Dirichlet and Neumann boundary conditions. DrainFlow is tested against five well-known integrated surface-subsurface flow benchmarks. DrainFlow as applied to some synthetic drainage study examples is quite flexible for changing all or part of the model dimensions as required by problem complexity, problem scale, and data availability. This flexibility enables DrainFlow to be modified to allow for changes in both scale and boundary conditions, as often encountered in real-world drainage studies. Compared to existing drainage models, DrainFlow has the advantage of estimating actual infiltration directly from the partial differential form of Richard's equation rather than through analytical or empirical infiltration approaches like the Green and Ampt equation.

  3. SUBSURFACE VISUAL ALARM SYSTEM ANALYSIS

    SciTech Connect

    D.W. Markman

    2001-08-06

    The ''Subsurface Fire Hazard Analysis'' (CRWMS M&O 1998, page 61), and the document, ''Title III Evaluation Report for the Surface and Subsurface Communication System'', (CRWMS M&O 1999a, pages 21 and 23), both indicate the installed communication system is adequate to support Exploratory Studies Facility (ESF) activities with the exception of the mine phone system for emergency notification purposes. They recommend the installation of a visual alarm system to supplement the page/party phone system The purpose of this analysis is to identify data communication highway design approaches, and provide justification for the selected or recommended alternatives for the data communication of the subsurface visual alarm system. This analysis is being prepared to document a basis for the design selection of the data communication method. This analysis will briefly describe existing data or voice communication or monitoring systems within the ESF, and look at how these may be revised or adapted to support the needed data highway of the subsurface visual alarm. system. The existing PLC communication system installed in subsurface is providing data communication for alcove No.5 ventilation fans, south portal ventilation fans, bulkhead doors and generator monitoring system. It is given that the data communication of the subsurface visual alarm system will be a digital based system. It is also given that it is most feasible to take advantage of existing systems and equipment and not consider an entirely new data communication system design and installation. The scope and primary objectives of this analysis are to: (1) Briefly review and describe existing available data communication highways or systems within the ESF. (2) Examine technical characteristics of an existing system to disqualify a design alternative is paramount in minimizing the number of and depth of a system review. (3) Apply general engineering design practices or criteria such as relative cost, and degree of

  4. Isotopic mixing model for quantifying contributions of soil water and groundwater in subsurface ('tile') drainage

    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.

  5. Evaluation on the Efficiency of Subsurface Drainage in Chiu-Fen Landslide at Northern Taiwan

    NASA Astrophysics Data System (ADS)

    Ying, L. Y.; Lin, D. G.

    2015-12-01

    For administrative district, the Chiu-Fen landslide is situated at northern Taiwan and comes within the jurisdiction of Ruei-Fang district, New Taipei City Government. Chiu-Fen village is a famous spot for sightseeing and tourism in Southeast Asia. In the last decade, for economic purpose, a vast area of slope land in Chiu-Fen area was reclaimed into business and commercial districts. However, due to the complicated geological and hydrological conditions, improper reclamation, and lack of appropriate soil and water conservation facilities, large scale landslides are frequently triggered by typhoon rainfall and causes damages to the transportation and residential building in the community. As a consequence, the government initiated a comprehensive field investigations and remediation plans to stabilize the landslide from 1997 and the remediation works were concentrated on subsurface drainages, namely the application of drainage well (a vertical shaft with multi-level horizontal drainage boreholes). To investigate the efficiency of drainage wells on the landslide, the A1-profile in the landslide which covers the drainage wells W2 and W4 was selected for a series of rainfall seepage and slope stability analyses. In addition, a 48-hrs design rainfall with return period of 25, 50 and 100 years based on the local meteorological data bank was adopted for the analyses. The numerical results indicate the factor safety FS of the three potential sliding surfaces within A1-profile are constantly keeping greater than one (FS > 1.0) and without decreasing with the elapsed time during rainfall. This implies that the subsurface drainage works can drain off the infiltrated rainwater from a high intensity and long duration rainfall and preserve the slope stability of landslides from deterioration. Finally, the efficiency of the drainage wells can be evaluated quantitatively in terms of the time-dependent factor of safety and the pore water pressure distribution on several potential

  6. Seasonal Patterns in Microbial Community Composition in Denitrifying Bioreactors Treating Subsurface Agricultural Drainage.

    PubMed

    Porter, Matthew D; Andrus, J Malia; Bartolerio, Nicholas A; Rodriguez, Luis F; Zhang, Yuanhui; Zilles, Julie L; Kent, Angela D

    2015-10-01

    Denitrifying bioreactors, consisting of water flow control structures and a woodchip-filled trench, are a promising approach for removing nitrate from agricultural subsurface or tile drainage systems. To better understand the seasonal dynamics and the ecological drivers of the microbial communities responsible for denitrification in these bioreactors, we employed microbial community "fingerprinting" techniques in a time-series examination of three denitrifying bioreactors over 2 years, looking at bacteria, fungi, and the denitrifier functional group responsible for the final step of complete denitrification. Our analysis revealed that microbial community composition responds to depth and seasonal variation in moisture content and inundation of the bioreactor media, as well as temperature. Using a geostatistical analysis approach, we observed recurring temporal patterns in bacterial and denitrifying bacterial community composition in these bioreactors, consistent with annual cycling. The fungal communities were more stable, having longer temporal autocorrelations, and did not show significant annual cycling. These results suggest a recurring seasonal cycle in the denitrifying bioreactor microbial community, likely due to seasonal variation in moisture content.

  7. Improving subsurface hydrology in Earth System Models

    NASA Astrophysics Data System (ADS)

    Volk, J. M.; Clark, M. P.; Swenson, S. C.; Lawrence, D. M.; Tyler, S. W.

    2015-12-01

    Hydrologic processes that govern storage and transport of soil water and groundwater can have strong dynamic relationships with biogeochemical and atmospheric processes. This understanding has lead to a push to improve subsurface hydrologic parametrization in Earth System Models. Here we present results related to improving the implementation of soil moisture distribution, groundwater recharge/discharge, and subsurface drainage in the Community Land Model (CLM) which is the land surface model in the Community Earth System Model. First we identified geo-climatically different locations around the world to develop test cases. For each case we compare the vertical soil moisture distribution from the different implementations of 1D Richards equation, considering the boundary conditions, the treatment of the groundwater sink term, the vertical discretization, and the time stepping schemes. Generally, large errors in the hydrologic mass balance within the soil column occur when there is a large vertical gradient in soil moisture or when there is a shallow water table within a soil column. We then test the sensitivity of the algorithmic parameters that control temporal discretization and error tolerance of the adaptive time-stepping scheme to help optimize its computational efficiency. In addition, we vary the spatial discretization of soil layers (i.e. quantity of layers and their thicknesses) to better understand the sensitivity of vertical discretization of soil columns on soil moisture variability in ESMs. We present multivariate and multi-scale evaluation for the different model options and suggest ways to move forward with future model improvements.

  8. 24 CFR 3285.604 - Drainage system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... § 3285.604 Drainage system. (a) Crossovers. Multi-section homes with plumbing in more than one section require drainage system crossover connections to join all sections of the home. The crossover design requirements are located in, and must be designed in accordance with, § 3280.610 of this chapter. (b)...

  9. Climate, Landscape, and Management Effects on Nitrate and Soluble Phosphorus concentrations in subsurface drainage discharge in the western Lake Erie basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface drainage, while an important and necessary agricultural production practice in the Midwest, contributes nitrate (NO3) and soluble phosphorus (P) to surface waters. The magnitude of NO3 and soluble P losses in subsurface drainage varies greatly by landscape, climate, and field management f...

  10. Evaluation of revised subsurface tile drainage algorithms in SWAT for a cold climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface tile drains in agricultural systems of the Mid-west U.S. are a major contributor of nitrate loadings to the Mississippi River Basin and contribute to hypoxic conditions in the northern Gulf of Mexico. Development of strategies to reduce nitrate loadings from these agricultural systems req...

  11. Antibiotic resistance and community analysis of surface and subsurface drainage waters in the South Fork Iowa River watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Midwest is a center for swine production leading to application of swine manure onto lands that have artificial subsurface drainage. Previous reports have indicated elevated levels of antibiotic resistance genes (ARGs) in surface water and groundwater around confined animal feeding operations w...

  12. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    SciTech Connect

    D.C. Randle

    2000-01-07

    The primary purpose of this document is to develop a preliminary high-level functional and physical control system architecture for the potential repository at Yucca Mountain. This document outlines an overall control system concept that encompasses and integrates the many diverse process and communication systems being developed for the subsurface repository design. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The Subsurface Repository Integrated Control System design will be composed of a series of diverse process systems and communication networks. The subsurface repository design contains many systems related to instrumentation and control (I&C) for both repository development and waste emplacement operations. These systems include waste emplacement, waste retrieval, ventilation, radiological and air monitoring, rail transportation, construction development, utility systems (electrical, lighting, water, compressed air, etc.), fire protection, backfill emplacement, and performance confirmation. Each of these systems involves some level of I&C and will typically be integrated over a data communications network throughout the subsurface facility. The subsurface I&C systems will also interface with multiple surface-based systems such as site operations, rail transportation, security and safeguards, and electrical/piped utilities. In addition to the I&C systems, the subsurface repository design also contains systems related to voice and video communications. The components for each of these systems will be distributed and linked over voice and video communication networks throughout the subsurface facility. The scope and primary objectives of this design analysis are to: (1) Identify preliminary system-level functions and interfaces (Section 6.2). (2) Examine the overall system complexity and determine how and on what levels the engineered process systems will be monitored, controlled, and

  13. Socially optimal drainage system and agricultural biodiversity: a case study for Finnish landscape.

    PubMed

    Saikkonen, Liisa; Herzon, Irina; Ollikainen, Markku; Lankoski, Jussi

    2014-12-15

    This paper examines the socially optimal drainage choice (surface/subsurface) for agricultural crop cultivation in a landscape with different land qualities (fertilities) when private profits and nutrient runoff damages are taken into account. We also study the measurable social costs to increase biodiversity by surface drainage when the locations of the surface-drained areas in a landscape affect the provided biodiversity. We develop a general theoretical model and apply it to empirical data from Finnish agriculture. We find that for low land qualities the measurable social returns are higher to surface drainage than to subsurface drainage, and that the profitability of subsurface drainage increases along with land quality. The measurable social costs to increase biodiversity by surface drainage under low land qualities are negative. For higher land qualities, these costs depend on the land quality and on the biodiversity impacts. Biodiversity conservation plans for agricultural landscapes should focus on supporting surface drainage systems in areas where the measurable social costs to increase biodiversity are negative or lowest.

  14. Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses.

    PubMed

    Feyereisen, Gary W; Francesconi, Wendy; Smith, Douglas R; Papiernik, Sharon K; Krueger, Erik S; Wente, Christopher D

    2015-03-01

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for movement of sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine the reduction in drainage effluent total suspended sediment (TSS) and phosphorus (P) concentrations and loads when open surface inlets were replaced with blind (in gravel capped with 30 cm of soil) or gravel (in very coarse sand/fine gravel) inlets. In Indiana, a pair of closed depressions in adjacent fields was fitted with open inlet tile risers and blind inlets in 2005 and monitored for flow and water chemistry. Paired comparisons on a storm event basis during the growing season for years 2006 to 2013 showed that TSS loads were 40.4 and 14.4 kg ha event for tile risers and blind inlets, respectively. Total P (TP) and soluble reactive P (SRP) loads were 66 and 50% less for the blind inlets, respectively. In Minnesota, TSS and SRP concentrations were monitored for 3 yr before and after modification of 24 open inlets to gravel inlets in an unreplicated large-field on-farm study. Median TSS concentrations were 97 and 8.3 mg L and median SRP concentrations were 0.099 and 0.064 mg L for the open inlet and gravel inlet periods, respectively. Median TSS and SRP concentrations were elevated for snowmelt vs. non-snowmelt seasons for open and gravel inlets. Both replacement designs reduced suspended sediment and P concentrations and loads. The Indiana study suggests blind inlets will be effective beyond a 10-yr service life.

  15. Occurrence of atrazine and degradates as contaminants of subsurface drainage and shallow groundwater

    SciTech Connect

    Jayachandran, K.; Steinheimer, T.R.; Moorman, T.B.

    1994-03-01

    Atrazine is a commonly used herbicide in corn (Zea mays L.) growing areas of the USA. Because of its heavy usage, moderate persistence, and mobility in soil, monitoring of atrazine movement under field conditions is essential to assess its potential to contaminate groundwater. Concentrations of atrazine, deisopropylatrazine (DIA), and deethlatraaine (DEA) were measured in subsurface drainage and shallow groundwater beneath continuous, no-till corn. Water samples were collected from the subsurface drain (tile) outlets and suction lysimeters in the growing seasons of 1990 and 1991, and analyzed for atrazine and two principle degradates won solid-phase extraction and HPLC. In 1990, atrazine concentration ranged from 1.3 to 5.1{mu}g L{sup -1} in tile-drain water and from 0.5 to 20.5 {mu}g L{sup -1} in lysimeter water. In general, concentrations of parent and degradates in solution were atrazine > DEA > DIA. Lesser levels of atrazine were measured in 1991 from Plots 2 and 4; however, greater concentrations of atrazine (6.0-8.4 {mu}g L{sup -1}) were measured from plot 5. Throughout the two growing seasons, atrazine concentration in Plot 5 tile-drain water was greater than that of Plots 2 and 4, suggesting a preferential movement of atrazine. Concentrations of DIA and DEA ranged from 0.1 to 2.2 and 0.9 to 3.2 {mu}g L{sup -1} respectively, indicating that the degradation products by themselves or in combination with parent atrazine can exceed the maximum contaminant level (mcl) of 3 {mu}g L{sup -1} even though atrazine by itself may be <3 {mu}g L{sup -1}. The deethylatrazine-to-atrazine ratio (DAR) is an indicator of residence time in soil during transport of atrazine to groundwater. In Plots 2 and 4, DAR values for tile-drain water ranged from 0.43 to 2.70 and 0.50 to 2.66 respectively. By comparison, a DAR of 0.38 to 0.60 was observed in Plot 5, suggesting less residence time in the soil. 38 refs., 5 figs., 4 tabs.

  16. Impacts of drainage water management on subsurface drain flow, nitrate concentration, and nitrate loads in Indiana

    EPA Science Inventory

    Drainage water management is a conservation practice that has the potential to reduce drainage outflow and nitrate (NO3) loss from agricultural fields while maintaining or improving crop yields. The goal of this study was to quantify the impact of drainage water management on dra...

  17. Systemic venous drainage: can we help Newton?

    PubMed

    Corno, Antonio F

    2007-06-01

    In recent years substantial progress occurred in the techniques of cardiopulmonary bypass, but the factor potentially limiting the flexibility of cardiopulmonary bypass remains the drainage of the systemic venous return. In the daily clinical practice of cardiac surgery, the amount of systemic venous return on cardiopulmonary bypass is directly correlated with the amount of the pump flow. As a consequence, the pump flow is limited by the amount of venous return that the pump is receiving. On cardiopulmonary bypass the amount of venous drainage depends upon the central venous pressure, the height differential between patient and inlet of the venous line into the venous reservoir, and the resistance in the venous cannula(s) and circuit. The factors determining the venous return to be taken into consideration in cardiac surgery are the following: (a) characteristics of the individual patient; (b) type of planned surgical procedure; (c) type of venous cannula(s); (d) type of circuit for cardiopulmonary bypass; (e) strategy of cardiopulmonary bypass; (f) use of accessory mechanical systems to increased the systemic venous return. The careful pre-operative evaluation of all the elements affecting the systemic venous drainage, including the characteristics of the individual patient and the type of required surgical procedure, the choice of the best strategy of cardiopulmonary bypass, and the use of the most advanced materials and tools, can provide a systemic venous drainage substantially better than what it would be allowed by the simple "Law of universal gravitation" by Isaac Newton.

  18. Late Pleistocene drainage systems beneath Delaware Bay

    USGS Publications Warehouse

    Knebel, H. J.; Circe, R.C.

    1988-01-01

    Analyses of an extensive grid of seismic-reflection profiles, along with previously published sedimentary data and geologic information from surrounding coastal areas, outline the ancestral drainage systems of the Delaware River beneath lower Delaware Bay. Major paleovalleys within these systems have southeast trends, relief of 10-35 m, widths of 1-8 km, and axial depths of 31-57 m below present sea level. The oldest drainage system was carved into Miocene sands, probably during the late Illinoian lowstand of sea level. It followed a course under the northern half of the bay, continued beneath the Cape May peninsula, and extended onto the present continental shelf. This system was buried by a transgressive sequence of fluvial, estuarine, and shallow-marine sediments during Sangamonian time. At the height of the Sangamonian sea-level transgression, littoral and nearshore processes built the Cape May peninsula southward over the northern drainage system and formed a contiguous submarine sedimentary ridge that extended partway across the present entrance to the bay. When sea level fell during late Wisconsinan time, a second drainage system was eroded beneath the southern half of the bay in response to the southerly shift of the bay mouth. This system, which continued across the shelf, was cut into Coastal Plain deposits of Miocene and younger age and included not only the trunk valley of the Delaware River but a large tributary valley formed by the convergence of secondary streams that drained the Delaware coastal area. During the Holocene rise of sea level, the southern drainage system was covered by a transgressive sequence of fluvial, estuarine, and paralic deposits that accumulated due to the passage of the estuarine circulation cell and to the landward and upward migration of coastal sedimentary environments. Some Holocene deposits have been scoured subsequently by strong tidal currents. The southward migration of the ancestral drainage systems beneath Delaware

  19. Preliminary results from agricultural drainage water management CIG projects on Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field demonstrations were monitored to compare the crop yields, drainage discharge, and nutrient loadings to streams from managed and unmanaged subsurface drainage systems. Paired drainage systems within the same field, under similar soil, area, cropping, and management conditions, were identified. ...

  20. 24 CFR 3280.610 - Drainage systems.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... water seal trap (§ 3280.606(a)). (2) The drainage system shall be designed to provide an adequate circulation of air in all piping with no danger of siphonage, aspiration, or forcing of trap seals under... equipped with a water-tight cap or plug matching the drain outlet. The cap or plug shall be...

  1. 24 CFR 3280.610 - Drainage systems.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... water seal trap (§ 3280.606(a)). (2) The drainage system shall be designed to provide an adequate circulation of air in all piping with no danger of siphonage, aspiration, or forcing of trap seals under... equipped with a water-tight cap or plug matching the drain outlet. The cap or plug shall be...

  2. Autonomous microexplosives subsurface tracing system final report.

    SciTech Connect

    Engler, Bruce Phillip; Nogan, John; Melof, Brian Matthew; Uhl, James Eugene; Dulleck, George R., Jr.; Ingram, Brian V.; Grubelich, Mark Charles; Rivas, Raul R.; Cooper, Paul W.; Warpinski, Norman Raymond; Kravitz, Stanley H.

    2004-04-01

    The objective of the autonomous micro-explosive subsurface tracing system is to image the location and geometry of hydraulically induced fractures in subsurface petroleum reservoirs. This system is based on the insertion of a swarm of autonomous micro-explosive packages during the fracturing process, with subsequent triggering of the energetic material to create an array of micro-seismic sources that can be detected and analyzed using existing seismic receiver arrays and analysis software. The project included investigations of energetic mixtures, triggering systems, package size and shape, and seismic output. Given the current absence of any technology capable of such high resolution mapping of subsurface structures, this technology has the potential for major impact on petroleum industry, which spends approximately $1 billion dollar per year on hydraulic fracturing operations in the United States alone.

  3. Heating systems for heating subsurface formations

    SciTech Connect

    Nguyen, Scott Vinh; Vinegar, Harold J.

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  4. Constructed wetland attenuation of nitrogen exported in subsurface drainage from irrigated and rain-fed dairy pastures.

    PubMed

    Tanner, C C; Nguyen, M L; Sukias, J P S

    2005-01-01

    Nitrogen removal performance is reported for constructed wetlands treating subsurface drainage from irrigated and rain-fed dairy pastures in North Island, New Zealand. Flow-proportional sampling of inflow and outflow concentrations were combined with continuous flow records to calculate mass balances for the wetlands. Drainage flows from the irrigated catchment were 2.5-4 fold higher and N exports up to 5 fold higher per unit area than for the rain-fed catchment. Hydraulic and associated N loadings to the wetlands were highly pulsed, associated with rainfall, soil water status, and irrigation events. Transient pulses of organic nitrogen were an important form of N loss from the rain-fed landscape in the first year, and were very effectively removed in the wetland (> 90%). Median nitrate concentrations of approximately 10 g m(-3) in the drainage inflows were reduced by 15-67% during passage through the wetlands and annual nitrate-N loads by 16-61% (38-31 7 g N m(-2)y(-1)). Generation in the wetlands of net ammoniacal-N and organic-N (irrigated site) partially negated reduction in nitrate-N loads. The results show that constructed wetlands comprising 1-2% of catchment area can provide moderate reductions in TN export via pastoral drainage, but performance is markedly influenced by variations in seasonal loading and establishment/maturation factors.

  5. Chest drainage systems in use

    PubMed Central

    Zisis, Charalambos; Tsirgogianni, Katerina; Lazaridis, George; Lampaki, Sofia; Baka, Sofia; Mpoukovinas, Ioannis; Karavasilis, Vasilis; Kioumis, Ioannis; Pitsiou, Georgia; Katsikogiannis, Nikolaos; Tsakiridis, Kosmas; Rapti, Aggeliki; Trakada, Georgia; Karapantzos, Ilias; Karapantzou, Chrysanthi; Zissimopoulos, Athanasios; Zarogoulidis, Konstantinos

    2015-01-01

    A chest tube is a flexible plastic tube that is inserted through the chest wall and into the pleural space or mediastinum. It is used to remove air in the case of pneumothorax or fluid such as in the case of pleural effusion, blood, chyle, or pus when empyema occurs from the intrathoracic space. It is also known as a Bülau drain or an intercostal catheter. Insertion of chest tubes is widely performed by radiologists, pulmonary physicians and thoracic surgeons. Large catheters or small catheters are used based on each situation that the medical doctor encounters. In the current review we will focus on the chest drain systems that are in use. PMID:25815304

  6. Variability of Near-stream, Sub-surface Major-ion and Tracer Concentrations in an Acid Mine Drainage Environment

    NASA Astrophysics Data System (ADS)

    Bencala, K. E.; Kimball, B. A.; Runkel, R. L.

    2006-12-01

    In acid mine drainage environments, tracer-injection and synoptic sampling approaches provide tools for making operational estimates of solute loading within a stream segment. Identifying sub-surface contaminant sources remains a challenge both for characterization of in-stream metal loading and hydrological process research. There is a need to quantitatively define the character and source of contaminants entering streams from ground-water pathways, as well as the potential for changes in water chemistry and contaminant concentrations along these flow paths crossing the sediment-water interface. Complicating the identification of inflows is the mixing of solute sources which may occur in the `near-stream' subsurface areas and specifically along hyporheic exchange flows (HEFs). In Mineral Creek (Silverton, Colorado), major-ion (SO42-, Cl-, Na+, Ca2+, Mg2+) meter-scale sampling shows that subsurface inflows and likely HEFs occur in a hydro- geochemical setting of significant, one order-of-magnitude, spatial variation in the solute concentrations. Transient Storage Models (TSMs) are a tool for interpreting the in-stream responses of solute transport in streams influenced by hyporheic exchange flows. Simulations using the USGS TSM code OTIS are interpreted as suggesting that in Mineral Creek the strong concentration `tailing' of bromide following the tracer injection occurred, at least in part, from HEFs in a hydro - solute transport setting of likely multiple, dispersed and mixed sources of water along a 64 m sub-reach of the nominally gaining stream. In acid mine drainage environments, the ability to distinguish between local and deep solute sources is critical in modeling reactive transport along the stream, as well as in identifying the geochemical evolution of dispersed, subsurface inflows thorough the catchment.

  7. Subsurface materials management and containment system

    DOEpatents

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2006-10-17

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  8. Subsurface materials management and containment system

    DOEpatents

    Nickelson, Reva A.; Richardson, John G.; Kosteinik, Kevin M.; Sloan, Paul A.

    2004-07-06

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  9. Use of Continuous Specific Conductance to Differentiate the Sources of Water to an Agricultural Stream With Subsurface Drainage Networks

    NASA Astrophysics Data System (ADS)

    Smith, E. A.; Thornburg, J.; Capel, P. D.

    2008-12-01

    The sources of water to natural streams include direct precipitation, overland flow, and ground-water inflow. In glaciated areas, the presence of artificial surface and subsurface drainage networks, a common practice for removing excess water from agricultural fields, provides additional pathways of water movement to the stream. The artificial drainage of agricultural fields allows rainfall to move quickly through the catchment to the stream transporting nutrients, pesticides and other agricultural-related constituents. A largely agricultural (about 90%), 31 km2 subcatchment of the South Fork of the Iowa River in north-central Iowa was studied for two years. Discharge and specific conductance (SC) were measured continuously and discreet water samples were obtained for analyses of nutrients and other constituents. SC is an electrical measurement of the total ion content in the water. The SC of the rain and ground-water is about 10 microS/cm and 800-1,200 microS/cm, respectively. The typical, base-flow SC of the stream is 700-800 microS/cm. Within minutes after a substantial rain event, the stream discharge increases and the SC decreases (often times below 200"nmicroS/cm). The rain water is processed through the catchment before it reaches the stream via direct overland flow, preferential flow to subsurface drains, vertical drains attached to subsurface drains in ponded areas, and/or soil infiltration to ground-water. Water moving through each of these pathways has different characteristic time scales and different degrees of interactions with the soil yielding different ionic content, thus different SC. Both the discharge and SC concurrently return to the typical base-flow values over the following days and weeks. This strong relation between rainfall, discharge and SC is used to calculate the relative importance and time scale of the various hydrologic pathways. In addition to the two-year stream record, complementary discharge and SC data were collected in two

  10. Representing natural and manmade drainage systems in an earth system modeling framework

    SciTech Connect

    Li, Hongyi; Wu, Huan; Huang, Maoyi; Leung, Lai-Yung R.

    2012-08-27

    Drainage systems can be categorized into natural or geomorphological drainage systems, agricultural drainage systems and urban drainage systems. They interact closely among themselves and with climate and human society, particularly under extreme climate and hydrological events such as floods. This editorial articulates the need to holistically understand and model drainage systems in the context of climate change and human influence, and discusses the requirements and examples of feasible approaches to representing natural and manmade drainage systems in an earth system modeling framework.

  11. Transport of tylosin and tylosin-resistance genes in subsurface drainage water from manured fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal agriculture appears to contribute to the spread of antibiotic resistance genes, but few studies have quantified gene transport in agricultural fields. The transport of tylosin, tylosin-resistance genes (erm B, F, A) and tylosin-resistant Enterococcus were measured in tile drainage water from ...

  12. Parallel heater system for subsurface formations

    DOEpatents

    Harris, Christopher Kelvin; Karanikas, John Michael; Nguyen, Scott Vinh

    2011-10-25

    A heating system for a subsurface formation is disclosed. The system includes a plurality of substantially horizontally oriented or inclined heater sections located in a hydrocarbon containing layer in the formation. At least a portion of two of the heater sections are substantially parallel to each other. The ends of at least two of the heater sections in the layer are electrically coupled to a substantially horizontal, or inclined, electrical conductor oriented substantially perpendicular to the ends of the at least two heater sections.

  13. Low temperature monitoring system for subsurface barriers

    DOEpatents

    Vinegar, Harold J.; McKinzie, II. Billy John

    2009-08-18

    A system for monitoring temperature of a subsurface low temperature zone is described. The system includes a plurality of freeze wells configured to form the low temperature zone, one or more lasers, and a fiber optic cable coupled to at least one laser. A portion of the fiber optic cable is positioned in at least one freeze well. At least one laser is configured to transmit light pulses into a first end of the fiber optic cable. An analyzer is coupled to the fiber optic cable. The analyzer is configured to receive return signals from the light pulses.

  14. A Physically-based Model for Surface and Subsurface Drainage from Porous Pavement Overlays

    NASA Astrophysics Data System (ADS)

    Eck, B. J.; Barrett, M.; Charbeneau, R. J.

    2010-12-01

    A thin layer of porous asphalt is commonly overlain on regular impermeable pavement to reduce splash and spray and improve visibility in wet weather. The porous layer often has a large hydraulic conductivity (>1cm/s) to encourage infiltration and drainage and therefore contains runoff when the rainfall intensity is low. However, under high rainfall intensity, the layer’s capacity is exceeded and drainage occurs both within and on top of the porous pavement. The problem is analogous to hill-slope hydrology of a thin aquifer where infiltration occurs rapidly and sheet flow is generated only when the aquifer is full. Common roadway features such as slope transitions and curvature make the drainage two-dimensional. A computer model was developed to study this coupled, unsteady process. The porous layer is modeled using the Boussinesq equation. The diffusion wave model is used for sheet flow over the pavement surface. This presentation summarizes the model’s development, shows that model results compare favorably to field measurements, and gives a case study in which the porous layer reduces the maximum sheet flow depth by 25% compared to conventional pavement.

  15. Multiobjective Statistical Method for Interior Drainage Systems

    NASA Astrophysics Data System (ADS)

    Haimes, Y. Y.; Loparo, K. A.; Olenik, S. C.; Nanda, S. K.

    1980-06-01

    In this paper the design of a levee drainage system is formulated as a multiobjective optimization problem in a probabilistic framework. The statistical nature of the problem is reflected by the probabilistic behavior of rainfall and river stage events in any given month. The multiobjective approach allows for the incorporation of noncommensurable objectives such as aesthetics, economics, and social issues into the optimization problem, providing a more realistic quantification of the impact of a flood or high water situation in an interior basin. A new method referred to as the multiobjective statistical method, which integrates statistical attributes with multiobjective optimization methodologies such as the surrogate worth trade-off method, is developed in this paper. A case study using data from the Moline area in Illinois suggests the use of the procedure.

  16. Air-water flow in subsurface systems

    NASA Astrophysics Data System (ADS)

    Hansen, A.; Mishra, P.

    2013-12-01

    Groundwater traces its roots to tackle challenges of safe and reliable drinking water and food production. When the groundwater level rises, air pressure in the unsaturated Vadose zone increases, forcing air to escape from the ground surface. Abnormally high and low subsurface air pressure can be generated when the groundwater system, rainfall, and sea level fluctuation are favorably combined [Jiao and Li, 2004]. Through this process, contamination in the form of volatile gases may diffuse from the ground surface into residential areas, or possibly move into groundwater from industrial waste sites. It is therefore crucial to understand the combined effects of air-water flow in groundwater system. Here we investigate theoretically and experimentally the effects of air and water flow in groundwater system.

  17. 24 CFR 3280.610 - Drainage systems.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... siphonage, aspiration, or forcing of trap seals under conditions of ordinary use. (b) Materials—(1) Pipe... iron, or other listed or approved materials. (2) Fittings. Drainage fittings shall be recessed drainage pattern with smooth interior waterways of the same diameter as the piping and shall be of a...

  18. Switching between hydrophobic and wettable conditions in soil: experiments to assess the influence of cracks, roots and subsurface drainage impedance

    NASA Astrophysics Data System (ADS)

    Urbanek, E.; Walsh, R. P. D.; Shakesby, R. A.

    2012-04-01

    Although much is known about soil hydrophobicity, assessments of the overall hydrological and erosional significance of the soil property in areas affected by it are greatly hampered by a lack of knowledge on switching between hydrophobic and hydrophilic states. This arises mainly because of (1) the destructive nature of methods of assessing hydrophobicity, (2) its often high local spatial variability and (3) difficulties of relating hydrophobicity results to meaningful soil moisture values. Also, very little is known about the influence which cracks and holes through hydrophobic soil and the presence or absence of subsurface impeding layers have on the 3D pattern and speed of hydrophobicity change during wetting and drying cycles. These issues form the focus of the present paper, which was carried out as part of the EU DESIRE Project. A laboratory experimental approach was adopted. Three different soils of equal initial hydrophibicity class when dry (18 % MED), but of contrasting texture and total carbon content, were investigated: (1) from the scrub-covered (dominated by Erica umbellata, Calluna vulgaris and Pterospartum tridentatum) Vale Torto catchment in Gois municipality, central Portugal (an area where the impacts of prescribed fire were being assessed); (2) soil around a Chamaecyparis lawsonia tree in South Wales; and (3) a vegetated coastal sand-dune location at Nicholaston, Gower Peninsula, South Wales. For the experiments, 106 samples of sieved (< 2 mm), dried soil were placed to a depth of 10 cm in standardized transparent pots (16.5 cm high, top diameter 16 cm, basal diameter 11 cm). Equal numbers of samples were prepared with either (i) five simulated holes, (ii) two simulated linear cracks (in both cases extending downwards to the sample base) and (iii) control soil samples without cracks or holes). Samples were also either (i) sealed at the base to create subsurface impeded drainage or (ii) provided with unimpeded basal drainage by insertion of

  19. Airport Pavement Drainage

    DTIC Science & Technology

    1990-06-01

    drainage layer and trench drains can be found in Cedergren (10). 4.2 COMPONENTS OF SUBSURFACE DRAINAGE SYSTEM 4.2.1 Outflow Once the water has found...According to Cedergren (10) the open graded aggregate can replace the normally used dense graded materials on an inch-for-inch basis. A main problem in...the perforated pipe to prevent fines from entering, Figure 4.24 (11). Cedergren (10) suggests that collector pipes should be 42 laid with the

  20. DEMONSTRATION BULLETIN: SUBSURFACE VOLATILIZATION AND VENTILATION SYSTEM - BROWN & ROOT ENVIRONMENTAL

    EPA Science Inventory

    The Subsurface Volatilization and Ventilation System (SVVS*) is an in-situ vacuum extraction/air sparging and bioremediation technology for the treatment of subsurface organic contamination in soil and groundwater. The technology, developed by Billings and Associates, Inc., and o...

  1. VIEW OF DRAINAGE SYSTEM AND WALL OF WELL AT CLOSER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF DRAINAGE SYSTEM AND WALL OF WELL AT CLOSER RANGE SHOWING VAULTED BRICK DRAIN AS IT ARCHED OUT FROM THE FOUNDATION (TO CENTER) - Belair, Tulip Grove Drive, Belair-at-Bowie, Bowie, Prince George's County, MD

  2. EXCAVATION OF EAST (FRONT) BASEMENT WELL AND DRAINAGE SYSTEM, WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXCAVATION OF EAST (FRONT) BASEMENT WELL AND DRAINAGE SYSTEM, WITH ARCHED ENTRY INTO BASEMENT UNDER FRONT ENTRY IN BACKGROUND, LOOKING NORTH (NOTE GALLETING IN BRICK FOUNDATION) - Belair, Tulip Grove Drive, Belair-at-Bowie, Bowie, Prince George's County, MD

  3. SITE TECHNOLOGY CAPSULE: SUBSURFACE VOLATILIZATION AND VENTILATION SYSTEM (SVVS)

    EPA Science Inventory

    The Subsurface Volatilization and Ventilation System is an integrated technology used for attacking all phases of volatile organic compound (VOC) contamination in soil and groundwater. The SVVS technology promotes insitu remediation of soil and groundwater contaminated with or-ga...

  4. SUBSURFACE VOLATIZATION AND VENTILATION SYSTEM (SVVS) - INNOVATIVE TECHNOLOGY REPORT

    EPA Science Inventory

    This report summarizes the findings associated with a Demonstration Test of Environmental Improvement Technologies’ (EIT) Subsurface Volatilization and Ventilation System (SVVS) process. The technology was evaluated under the EPA Superfund Innovative Technology Evaluation (SITE) ...

  5. Filter Fabrics for Airport Drainage.

    DTIC Science & Technology

    1979-09-01

    Systems for *r- field Pavements," Harry R. Cedergren . d. "Development of Guidelines for the Design of Subsurfac( Drainage Systems for Highway Pavement...Structural 4Sectic s," H. R. Cedergren , J. A. Arman, and K. H. O’Brien. e. Drainage of Highway and Airfield Pavements, Harry R. Cedergren .> Five...by Cedergren (974).5 Additionally, several references were used, particularly those describing experimental anu construction prolects using filter

  6. Analysis and modeling of flooding in urban drainage systems

    NASA Astrophysics Data System (ADS)

    Schmitt, Theo G.; Thomas, Martin; Ettrich, Norman

    2004-12-01

    The European research project in the EUREKA framework, RisUrSim (Σ!2255) is presented. The project consortium includes industrial mathematics and water engineering research institutes, municipal drainage works as well as an insurance company. The overall objective has been the development of an integrated planning and management tool to allow cost effective management for urban drainage systems. The paper outlines the regulatory background of European Standard EN 752 defining flood frequency as the one hydraulic performance criterion. The phenomenon of urban flooding caused by surcharged sewer systems in urban drainage systems is analyzed leading to the necessity of dual drainage modeling. A detailed dual drainage simulation model is described based upon hydraulic flow routing procedures for surface flow and pipe flow. Special consideration is given to the interaction between surface and sewer flow in order to most accurately compute water levels above ground as a basis for further assessment of possible damage costs. The model application is presented for small case study in terms of data needs, model verification and first simulation results.

  7. Crop yield summary for three wetland reservoir subirrigation systems in northwest Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wetland Reservoir Subirrigation Systems (WRSIS) are innovative agricultural water management and recycling systems comprised of three main components; a constructed wetland, a water storage reservoir, and cropland containing subsurface drainage pipe systems. Surface runoff and subsurface drainage f...

  8. Quaternary Reorganization of North American Mid-continent Drainage Systems

    NASA Astrophysics Data System (ADS)

    Carson, E. C.; Rawling, J. E., III; Attig, J. W.; Bates, B. R.

    2013-12-01

    Identification of ancestral drainage systems in the North American mid-continent has been a topic of research and debate among geologists since the middle of the 19th Century. Over time our understanding of the significance of Quaternary glaciations in reshaping drainage patterns has grown. The ancestral Teays River, which drained large areas of the central Appalachians and flowed westward across Indiana and western Illinois, was dammed multiple times by Quaternary glaciers before finally being rerouted to the course of the modern central Ohio River. Similarly, the northward-flowing ancestral Pittsburgh River was dammed by pre-Illinoian glaciers; subsequent stream piracy converted this river system into the modern Allegheny, Monongahela and uppermost Ohio Rivers. Deposits and geomorphic features along the westward-flowing lower Wisconsin River indicate that the modern upper Mississippi River and Wisconsin River may have experienced a similar history of ice blockage, stream piracy, and radical rerouting. Coring into the Bridgeport strath terrace along the lower Wisconsin River reveals that the bedrock surface dips to the east, indicating the valley was cut by an eastward-flowing river. We believe the most likely scenario following this interpretation is that an ancestral river flowing along the modern upper Mississippi River valley made a sharp bend at Prairie du Chien, WI, and flowed eastward along the valley occupied by the modern lower Wisconsin River. This river, referred to here as the Wyalusing River, likely flowed northeastward into the Great Lakes (St. Lawrence) drainage until that path was blocked by ice advancing from the northwest. Subsequent stream piracy immediately south of the modern confluence of the Mississippi and Wisconsin Rivers rerouted these streams, converting them to the headwaters of the greater Mississippi drainage. The combined rerouting of these river systems into entirely different drainage basins necessitates significant fundamental

  9. Effect of dripline flushing on subsurface drip irrigation systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The velocity of dripline flushing in subsurface drip irrigation (SDI) systems affects system design, cost, management, performance, and longevity. A 30-day field study was conducted at Kansas State University to analyze the effect of four targeted flushing velocities (0.23, 0.30, 0.46, and 0.61 m/s)...

  10. Effects of dripline flushing on subsurface drip irrigation systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The velocity of dripline flushing in subsurface drip irrigation (SDI) systems affects system design, cost, management, performance, and longevity. A 30-day field study was conducted at Kansas State University to analyze the effect of four targeted flushing velocities (0.23, 0.30, 0.46, and 0.61 m/s)...

  11. Condensed research overview of agricultural drainage pipe detection and assessment using ground penetrating radar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural subsurface drainage practices are employed in many places throughout the world to remove excess water from soil, thereby improving crop production. In order to improve and evaluate the efficiency of these subsurface drainage systems, non-destructive methods are needed to not only locate...

  12. Yield Response and Economics of Shallow Subsurface Drip Irrigation Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field tests were conducted using shallow subsurface drip irrigation (S3DI) on cotton (Gossypium hirsutum, L.), corn (Zea mays, L.), and peanut (Arachis hypogeae, L.) in rotation to investigate yield potential and economic sustainability of this irrigation system technique over a six year period. Dri...

  13. EXCAVATION OF EAST (FRONT) BASEMENT WELL AND DRAINAGE SYSTEM, WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXCAVATION OF EAST (FRONT) BASEMENT WELL AND DRAINAGE SYSTEM, WITH ARCHED ENTRY INTO BASEMENT UNDER FRONT ENTRY IN BACKGROUND, LOOKING NORTH (NOTE GALLETING IN BRICK FOUNDATION) BUT CLOSER RANGE SHOWING BRICK STRUCTURE WHICH CARRIED WATER FROM THE GUTTER DRAIN PIPE INTO THE BRICK DRAIN ALONG THE GROUND AND AWAY FROM THE FOUNDATION OF THE HOUSE - Belair, Tulip Grove Drive, Belair-at-Bowie, Bowie, Prince George's County, MD

  14. Approach for evaluating inundation risks in urban drainage systems.

    PubMed

    Zhu, Zhihua; Chen, Zhihe; Chen, Xiaohong; He, Peiying

    2016-05-15

    Urban inundation is a serious challenge that increasingly confronts the residents of many cities, as well as policymakers. Hence, inundation evaluation is becoming increasingly important around the world. This comprehensive assessment involves numerous indices in urban catchments, but the high-dimensional and non-linear relationship between the indices and the risk presents an enormous challenge for accurate evaluation. Therefore, an approach is hereby proposed to qualitatively and quantitatively evaluate inundation risks in urban drainage systems based on a storm water management model, the projection pursuit method, the ordinary kriging method and the K-means clustering method. This approach is tested using a residential district in Guangzhou, China. Seven evaluation indices were selected and twenty rainfall-runoff events were used to calibrate and validate the parameters of the rainfall-runoff model. The inundation risks in the study area drainage system were evaluated under different rainfall scenarios. The following conclusions are reached. (1) The proposed approach, without subjective factors, can identify the main driving factors, i.e., inundation duration, largest water flow and total flood amount in this study area. (2) The inundation risk of each manhole can be qualitatively analyzed and quantitatively calculated. There are 1, 8, 11, 14, 21, and 21 manholes at risk under the return periods of 1-year, 5-years, 10-years, 20-years, 50-years and 100-years, respectively. (3) The areas of levels III, IV and V increase with increasing rainfall return period based on analyzing the inundation risks for a variety of characteristics. (4) The relationships between rainfall intensity and inundation-affected areas are revealed by a logarithmic model. This study proposes a novel and successful approach to assessing risk in urban drainage systems and provides guidance for improving urban drainage systems and inundation preparedness.

  15. Drilling systems for extraterrestrial subsurface exploration.

    PubMed

    Zacny, K; Bar-Cohen, Y; Brennan, M; Briggs, G; Cooper, G; Davis, K; Dolgin, B; Glaser, D; Glass, B; Gorevan, S; Guerrero, J; McKay, C; Paulsen, G; Stanley, S; Stoker, C

    2008-06-01

    Drilling consists of 2 processes: breaking the formation with a bit and removing the drilled cuttings. In rotary drilling, rotational speed and weight on bit are used to control drilling, and the optimization of these parameters can markedly improve drilling performance. Although fluids are used for cuttings removal in terrestrial drilling, most planetary drilling systems conduct dry drilling with an auger. Chip removal via water-ice sublimation (when excavating water-ice-bound formations at pressure below the triple point of water) and pneumatic systems are also possible. Pneumatic systems use the gas or vaporization products of a high-density liquid brought from Earth, gas provided by an in situ compressor, or combustion products of a monopropellant. Drill bits can be divided into coring bits, which excavate an annular shaped hole, and full-faced bits. While cylindrical cores are generally superior as scientific samples, and coring drills have better performance characteristics, full-faced bits are simpler systems because the handling of a core requires a very complex robotic mechanism. The greatest constraints to extraterrestrial drilling are (1) the extreme environmental conditions, such as temperature, dust, and pressure; (2) the light-time communications delay, which necessitates highly autonomous systems; and (3) the mission and science constraints, such as mass and power budgets and the types of drilled samples needed for scientific analysis. A classification scheme based on drilling depth is proposed. Each of the 4 depth categories (surface drills, 1-meter class drills, 10-meter class drills, and deep drills) has distinct technological profiles and scientific ramifications.

  16. Modeling leakage pathways in subsurface formations. Fluid drainage through multiple fractures in porous media: Insights from Hele Shaw cell experiments

    NASA Astrophysics Data System (ADS)

    Ray, Sujata

    2017-04-01

    Arresting the recent observed warming of the earth's climate is a challenge requiring the reduction of anthropogenic emissions of carbon dioxide. One option for reducing emissions into the atmosphere is to capture and sequester the released carbon dioxide in geological formations. However, potential geological storage first requires a risk assessment of carbon dioxide escaping to overlying layers and back to the atmosphere through leakage pathways in the formation. This, in turn, requires an understanding of fluid flow through the leakage pathways. In this study, the effect of leakage pathways on the flow of a gravity current was investigated, using an analogue system, a Hele-Shaw cell. Fluid was introduced through the top edge of the cell and flowed out through one or more holes in its impermeable base. The height of the accumulated fluid above the base of the cell at various points along its length and the outflow rate of fluid through the holes was measured. This measurement was conducted with varying conditions of the location, number and strength of source as well as the location and number of holes. At steady state, the fluid motion was in accordance with Darcy's law for horizontal flow in a long thin current. In another set of experiments, in which inflow was stopped and the fluid was allowed to drain out of a single open hole, the outflow rate was in accordance with Darcy's law for one-dimensional flow in the vertical direction until the fluid height above the hole fell below a certain limit. This threshold height was found to be 1.3 cm, which was similar in magnitude to the length of the hole. A time series of photographs tracked the flow of colored dye. The photographs demonstrated that at steady state the fluid traveled for some distance beyond the hole before draining through it. This implies that contaminants may be transported in a formation even beyond an outlet before finally draining out through it. The photographs also documented the shape of the

  17. Numeric Modeling of Valley Networks and Drainage Systems on Mars

    NASA Astrophysics Data System (ADS)

    Vidal, A.

    2006-12-01

    Valley networks observed on Mars are often invoked to support the historical presence of water on the surface of Mars. There is a need for quantification of these networks and the drainage processes associated with them. Numerical modeling of these streams and drainage basins within a GIS environment allows for rapid assessment of hydrologic surface processes. In this study, several areas of valley networks which had been previously mapped visually using Viking, MOC, and MOLA datasets were re-examined using numeric processes and tools available in ArcGIS. Specifically, stream length and drainage density were quantified using the MOLA gridded DEM and ArcGIS tools. This process is significantly faster than the visual identification and delineation techniques used in the past. The project sought to test whether or not computer-assisted techniques were comparable in accuracy and precision to previous studies using visual techniques. To do this, two quadrangles previously visually mapped by Carr (1995) and Hynek and Phillips (2003) were analyzed. Total valley network length at the first site was found to be 18,300 km, compared to previous estimates of 1,308 km (Carr) and 11,100 km (Hynek and Phillips). Drainage density was calculated to be 0.0605/km, compared to previous estimates of 0.0076/km (Carr) and 0.065/km (Hynek and Phillips). The highest stream order found was 5th, compared to 3rd (Carr) and 6th (Hynek and Phillips). In the second quadrangle, total valley network length was measured at 4,010 km, compared to 453 km and 3,496 km. The drainage density was calculated to be 0.068/km, compared to 0.011/km and 0.082/km. The highest stream order found was 4th, compared to 2nd and 5th. Results were very similar to those using visual interpretation of MOC shaded relief by Hynek and Phillips. A difference in stream order, however, suggests that the computer-aided technique may not connect systems that visually have been connected. Still, automated results offer an

  18. Transient age distributions in subsurface hydrologic systems

    NASA Astrophysics Data System (ADS)

    Engdahl, Nicholas B.; McCallum, James L.; Massoudieh, Arash

    2016-12-01

    Transient age distributions have received relatively little attention in the literature over the years compared to their steady-state counterparts. All natural systems are transient given enough time and it is becoming increasingly clear that understanding these effects and how they deviate from steady conditions will be important in the future. This article provides a high-level overview of the equations, techniques, and challenges encountered when considering transient age distributions. The age distribution represents the amount of water in a sample belonging to a particular age and the transient case implies that sampling the same location at two different times will result in different age distributions. These changes may be caused by transience in the boundary conditions, forcings (inputs), or physical changes in the geometry of the flow system. The governing equation for these problems contains separate dimensions for age and time and its solutions are more involved than the solute transport or steady-state age equations. Despite the complexity, many solutions have been derived for simplified, but transient, approximations and several numerical techniques exist for modeling more complex transient age distributions. This paper presents an overview of the existing solutions and contributes new examples of transient characteristic solutions and transient particle tracking simulations. The limitations for applying the techniques described herein are no longer theoretical or technological, but are now dominated by uncertainty in the physical properties of the flow systems and the lack of data for the historic inputs.

  19. SUBSURFACE BARRIER VALIDATION WITH THE SEAFACE SYSTEM

    SciTech Connect

    Sandra Dalvit Dunn

    1997-11-30

    The overall objective of the effort was to develop and demonstrate an integrated methodology and field system to evaluate the integrity of in situ, impermeable barriers constructed in the vadose zone. An autonomous, remotely accessible, automatic monitoring and analysis system was designed and fabricated. It was thoroughly tested under field conditions, and was able to function as designed throughout the test period. Data inversion software was developed with enhanced capabilities over the previous prototype version, and integrated with the monitoring system for real time operation. Analytical simulations were performed to determine the inversion code's sensitivity to model parameters. Numerical simulations were performed to better understand how typical field conditions differ from the ideal model(s) which are used (or have been developed for use) in the inversion code and to further validate the flux limited forward model developed for use with the system. Results from the analytical and numerical assessment of the inversion code showed that the SEAtrace{trademark} approach could locate leaks within 0.4 to 1.2 m. Leak size determination was less accurate, but produced results within a factor of 3 to 8 for leaks in the 2.5 to 10 cm diameter range. The smallest engineered leak in the test 1.1 cm diameter, could be located but its size estimate was high by a factor of 30. Data analysis was performed automatically after each gas scan was completed, yielding results in less than thirty minutes, although the bulk of the results reported required post test data analysis to remove effects of high background concentrations. The field test of the integrated system was problematic, primarily due to unanticipated, unintentional leaks formed in the impermeable liner. The test facility constructed to proof the system was ambitious, initially having 11 engineered leaks of various dimensions that could be independently operated. While a great deal of care went into the

  20. Hormones, sterols, and fecal indicator bacteria in groundwater, soil, and subsurface drainage following a high single application of municipal biosolids to a field.

    PubMed

    Gottschall, N; Topp, E; Edwards, M; Payne, M; Kleywegt, S; Russell, P; Lapen, D R

    2013-04-01

    A land application of dewatered municipal biosolids (DMB) was conducted on an agricultural field in fall 2008 at a rate of 22Mg dry weight (dw) ha(-1). Pre- and post- application, hormone, sterol and fecal indicator bacteria concentrations were measured in tile drainage water, groundwater (2, 4, 6m depth), surface soil cores, and DMB aggregates incorporated in the soil (∼0.2m depth) for a period of roughly 1year post-application. Hormones and sterols were detected up to 1year post-application in soil and in DMB aggregates. Hormone (androsterone, desogestrel, estrone) contamination was detected briefly in tile water samples (22d and ∼2months post-app), at lowngL(-1) concentrations (2-34ngL(-1)). Hormones were not detected in groundwater. Sterols were detected in tile water throughout the study period post-application, and multiple fecal sterol ratios suggested biosolids as the source. Coprostanol concentrations in tile water peaked at >1000ngL(-1) (22d post-app) and were still >100ngL(-1) at 6months post-application. Fecal indicator bacteria were detected throughout the study period in tile water, groundwater (⩽2m depth), soil and DMB aggregate samples. These bacteria were strongly linearly related to coprostanol in tile water (R(2)>0.92, p<0.05). The limited transport of hormones and sterols to tile drainage networks may be attributed to a combination of the hydrophobicity of these compounds and limited macroporosity of the field soil. This transitory contamination from hormones and sterols is unlikely to result in any significant pulse exposure risk in subsurface drainage and groundwater.

  1. Method of sealing casings of subsurface materials management system

    DOEpatents

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2007-02-06

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  2. Methods and system for subsurface stabilization using jet grouting

    DOEpatents

    Loomis, Guy G.; Weidner, Jerry R.; Farnsworth, Richard K.; Gardner, Bradley M.; Jessmore, James J.

    1999-01-01

    Methods and systems are provided for stabilizing a subsurface area such as a buried waste pit for either long term storage, or interim storage and retrieval. A plurality of holes are drilled into the subsurface area with a high pressure drilling system provided with a drill stem having jet grouting nozzles. A grouting material is injected at high pressure through the jet grouting nozzles into a formed hole while the drill stem is withdrawn from the hole at a predetermined rate of rotation and translation. A grout-filled column is thereby formed with minimal grout returns, which when overlapped with other adjacent grout-filled columns encapsulates and binds the entire waste pit area to form a subsurface agglomeration or monolith of grout, soil, and waste. The formed monolith stabilizes the buried waste site against subsidence while simultaneously providing a barrier against contaminate migration. The stabilized monolith can be left permanently in place or can be retrieved if desired by using appropriate excavation equipment. The jet grouting technique can also be utilized in a pretreatment approach prior to in situ vitrification of a buried waste site. The waste encapsulation methods and systems are applicable to buried waste materials such as mixed waste, hazardous waste, or radioactive waste.

  3. IMPACT OF REDOX DISEQUILIBRIA ON CONTAMINANT TRANSPORT AND REMEDIATION IN SUBSURFACE SYSTEMS

    EPA Science Inventory

    Partitioning to mineral surfaces exerts significant control on inorganic contaminant transport in subsurface systems. Remedial technologies for in-situ treatment of subsurface contamination are frequently designed to optimize the efficiency of contaminant partitioning to solid s...

  4. Site Recommendation Subsurface Layout

    SciTech Connect

    C.L. Linden

    2000-06-28

    The purpose of this analysis is to develop a Subsurface Facility layout that is capable of accommodating the statutory capacity of 70,000 metric tons of uranium (MTU), as well as an option to expand the inventory capacity, if authorized, to 97,000 MTU. The layout configuration also requires a degree of flexibility to accommodate potential changes in site conditions or program requirements. The objective of this analysis is to provide a conceptual design of the Subsurface Facility sufficient to support the development of the Subsurface Facility System Description Document (CRWMS M&O 2000e) and the ''Emplacement Drift System Description Document'' (CRWMS M&O 2000i). As well, this analysis provides input to the Site Recommendation Consideration Report. The scope of this analysis includes: (1) Evaluation of the existing facilities and their integration into the Subsurface Facility design. (2) Identification and incorporation of factors influencing Subsurface Facility design, such as geological constraints, thermal loading, constructibility, subsurface ventilation, drainage control, radiological considerations, and the Test and Evaluation Facilities. (3) Development of a layout showing an available area in the primary area sufficient to support both the waste inventories and individual layouts showing the emplacement area required for 70,000 MTU and, if authorized, 97,000 MTU.

  5. Agricultural drainage pipe detection using ground penetrating radar: Effects of antenna orientation relative to drainage pipe directional trend

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Locating buried agricultural drainage pipes is a difficult problem confronting farmers and land improvement contractors, especially in the Midwest U.S., where the removal of excess soil water using subsurface drainage systems is a common farm practice. Enhancing the efficiency of soil water removal ...

  6. A GPR agricultural drainage pipe detection case study: Effects of antenna orientation relative to drainage pipe directional trend

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Locating buried drainage pipes is a difficult task confronting farmers and land improvement contractors, especially in the Midwest U.S., where the removal of excess soil water using subsurface drainage systems is a common farm practice. Enhancing the efficiency of soil water removal on land containi...

  7. Regional view of a Trans-African Drainage System

    PubMed Central

    Abdelkareem, Mohamed; El-Baz, Farouk

    2014-01-01

    Despite the arid to hyperarid climate of the Great Sahara of North Africa, pluvial climates dominated the region. Radar data shed some light on the postulated Trans-African Drainage System and its relationship to active and inactive tributaries of the Nile basin. Interpretations of recent elevation data confirm a source of the river water from the Red Sea highlands did not connect the Atlantic Ocean across Tushka basin, highlands of Uwinate and Darfur, and Chad basin, but northward to the ancestral Nile Delta. Elements of topography and climate were considered. They show that the former segments of the Nile closely mirror present-day tributaries of the Nile basin in drainage geometry, landscape, and climate. A rainfall data interpolation scenario revealed that this basin received concurrent runoff from both flanks such as Gabgaba-Allaqi to the east and Tushka basin to the west, similar to present-day Sobat and White Nile tributaries, respectively. Overall the western tributaries such as those of Tushka basin and Howar lead to the Nile, which was (and still is) the biggest river system in Africa. PMID:26257941

  8. Subsurface barrier validation with the SEAtrace{trademark} system

    SciTech Connect

    Sandra Dalvit Dunn; William Lowry; Veraun Chipman

    1999-09-01

    Under contract to the Department of Energy, Science and Engineering Associates has completed development and testing of a subsurface barrier verification and monitoring system. This system, called SEAtrace{trademark}, is able to locate and size leaks with a high degree of accuracy in subsurface barriers that are emplaced in an unsaturated medium. It uses gaseous tracer injection, in-field real-time monitoring, and real time data analysis to evaluate barrier integrity. The approach is: Conservative as it measures vapor leaks in a containment system whose greatest risk is posed by liquid leaks; Applicable to any impermeable type of barrier emplacement technology in the unsaturated zone; Inexpensive as it uses readily available, non-toxic, nonhazardous gaseous tracers, does not require an inordinately large number of sampling points, and injection and sampling points can be emplaced by direct push techniques; Capable of assessing not only a barrier's initial integrity, but can also provide long-term monitoring. To date, six demonstrations of the system have been completed. Results from two of the demonstrations are detailed in this report. They include the final developmental demonstration of the SEAtrace system and a comparison demonstration of two tracer based verification technologies. The final developmental demonstration of SEAtrace was completed at a naval facility in Brunswick, Maine. The demonstration was funded solely by the DOE and was performed in cooperation with the US Navy, the Environmental Protection Agency, and the Maine Department of Environmental Protection.

  9. Modeling Subsurface Storm and Tile Drain Systems in GSSHA with SUPERLINK

    DTIC Science & Technology

    2014-09-01

    ER D C/ CH L TR -1 4- 11 System-Wide Water Resources Program (SWWRP) Modeling Subsurface Storm and Tile Drain Systems in GSSHA with...System-Wide Water Resources Program (SWWRP) ERDC/CHL TR-14-11 September 2014 Modeling Subsurface Storm and Tile Drain Systems in GSSHA with...loadings and pollution abatement. A subsurface storm drain model, called SUPERLINK, has been incorporated into GSSHA to allow the model to

  10. Illinois drainage water management demonstration project

    USGS Publications Warehouse

    Pitts, D.J.; Cooke, R.; Terrio, P.J.; ,

    2004-01-01

    Due to naturally high water tables and flat topography, there are approximately 4 million ha (10 million ac) of farmland artificially drained with subsurface (tile) systems in Illinois. Subsurface drainage is practiced to insure trafficable field conditions for farm equipment and to reduce crop stress from excess water within the root zone. Although drainage is essential for economic crop production, there have been some significant environmental costs. Tile drainage systems tend to intercept nutrient (nitrate) rich soil-water and shunt it to surface water. Data from numerous monitoring studies have shown that a significant amount of the total nitrate load in Illinois is being delivered to surface water from tile drainage systems. In Illinois, these drainage systems are typically installed without control mechanisms and allow the soil to drain whenever the water table is above the elevation of the tile outlet. An assessment of water quality in the tile drained areas of Illinois showed that approximately 50 percent of the nitrate load was being delivered through the tile systems during the fallow period when there was no production need for drainage to occur. In 1998, a demonstration project to introduce drainage water management to producers in Illinois was initiated by NRCS4 An initial aspect of the project was to identify producers that were willing to manage their drainage system to create a raised water table during the fallow (November-March) period. Financial assistance from two federal programs was used to assist producers in retrofitting the existing drainage systems with control structures. Growers were also provided guidance on the management of the structures for both water quality and production benefits. Some of the retrofitted systems were monitored to determine the effect of the practice on water quality. This paper provides background on the water quality impacts of tile drainage in Illinois, the status of the demonstration project, preliminary

  11. TITLE III EVALUATION REPORT FOR THE SUBSURFACE LIGHTING SYSTEM

    SciTech Connect

    L.J. Fernandez

    1998-09-09

    The objective of this evaluation is to provide recommendations to ensure consistency between the technical baseline requirements, baseline design, and the as-constructed Subsurface Lighting System. Recommendations for resolving discrepancies between the as-constructed system, and the technical baseline requirements are included in this report. Cost and Schedule estimates are provided for all recommended modifications. This report does not address items which do not meet current safety or code requirements. These items are identified to the CMO and immediate action is taken to correct the situation. The report does identify safety and code items for which the A/E is recommending improvements. The recommended improvements will exceed the minimum requirements of applicable code and safety guide lines. These recommendations are intended to improve and enhance the operation and maintenance of the facility.

  12. The evolution of cave systems from the surface to subsurface

    SciTech Connect

    Loucks, R.G.; Handford, C.R.

    1996-12-31

    Many carbonate reservoirs are the result of cave-forming processes. The origin and recognition of fractures, breccias, and sediment fills associated with paleocaves were determined through the study of modern and paleocaves systems. Cave formation and destruction are the products of near-surface processes. Near-surface processes include solutional excavation, clastic and chemical sedimentation, and collapse of cave walls and ceilings. Cave sediment is derived from inside and/or outside the system. Depositional mechanisms include suspension, tractional, mass-flow and rock-fall. Collapse of ceilings and walls from chaotic breakdown breccias. These piles can be tens of meters thick and contain large voids and variable amounts of matrix. Cave-roof crackle breccia forms from stress-and tension-related fractures in cave-roof strata. As the cave-bearing strata subside into the subsurface, mechanical compaction increases and restructures the existing breccias and remaining cavities. Fracture porosity increases and breccia and vug porosity decreases. Large cavities collapse forming burial chaotic breakdown breccias. Differentially compacted strata over the collapsed chamber fracture and form burial cave-roof crackle breccias. Continued burial leads to more extensive mechanical compaction causing previously formed clasts to fracture and pack closer together. The resulting product is a rebrecciated chaotic breakdown breccia composed predominantly of small clasts. Rebrecciated blocks are often overprinted by crackling. Subsurface paleocave systems commonly have a complex history with several episodes of fracturing and brecciation. The resulting collapsed-paleocave reservoir targets are not single collapsed passages of tens of feet across, but are homogenized collapsed-cave systems hundreds to several thousand feet across.

  13. The evolution of cave systems from the surface to subsurface

    SciTech Connect

    Loucks, R.G. ); Handford, C.R. )

    1996-01-01

    Many carbonate reservoirs are the result of cave-forming processes. The origin and recognition of fractures, breccias, and sediment fills associated with paleocaves were determined through the study of modern and paleocaves systems. Cave formation and destruction are the products of near-surface processes. Near-surface processes include solutional excavation, clastic and chemical sedimentation, and collapse of cave walls and ceilings. Cave sediment is derived from inside and/or outside the system. Depositional mechanisms include suspension, tractional, mass-flow and rock-fall. Collapse of ceilings and walls from chaotic breakdown breccias. These piles can be tens of meters thick and contain large voids and variable amounts of matrix. Cave-roof crackle breccia forms from stress-and tension-related fractures in cave-roof strata. As the cave-bearing strata subside into the subsurface, mechanical compaction increases and restructures the existing breccias and remaining cavities. Fracture porosity increases and breccia and vug porosity decreases. Large cavities collapse forming burial chaotic breakdown breccias. Differentially compacted strata over the collapsed chamber fracture and form burial cave-roof crackle breccias. Continued burial leads to more extensive mechanical compaction causing previously formed clasts to fracture and pack closer together. The resulting product is a rebrecciated chaotic breakdown breccia composed predominantly of small clasts. Rebrecciated blocks are often overprinted by crackling. Subsurface paleocave systems commonly have a complex history with several episodes of fracturing and brecciation. The resulting collapsed-paleocave reservoir targets are not single collapsed passages of tens of feet across, but are homogenized collapsed-cave systems hundreds to several thousand feet across.

  14. Feasibility study of a self-remediation system for mine drainage using its thermal energy

    NASA Astrophysics Data System (ADS)

    Oh, Chamteut; Cheong, Youngwook; Yim, Giljae; Ji, Sangwoo

    2016-04-01

    Mine drainage is defined as the water which is discharged to the ground surface through shafts and/or cracks formed by mining activities. Typically, mine drainage features high concentration of acidity and metals since it passes through the underground. Therefore, for the purpose of protecting the surrounding natural environment, mine drainage should be remediated before being discharged to nature. Mine drainage, due to its nature of being retained underground, shows constant temperature which is independent from the temperature of the atmosphere above ground. This condition allows mine drainage to become a promising renewable energy source since energy can be recovered from water with constant temperature. In this research, a self-remediation system is proposed which remediates the mine drainage through electrochemical reactions powered by the thermal energy of mine drainage. High energy efficiency is able to be achieved by shortening the distance between the energy source and consumption, and therefore, this system has a strong advantage to be actualized. A feasibility study for the system was conducted in this research where the thermal energy of mine drainage over time and depth was calculated as energy supply and the required electrical energy for remediating the mine drainage was measured as energy consumption. While the technology of converting thermal energy directly into electrical energy is yet to be developed, energy balance analysis results showed that the proposed self-remediation system is theoretically possible.

  15. Comparative analysis of the outflow water quality of two sustainable linear drainage systems.

    PubMed

    Andrés-Valeri, V C; Castro-Fresno, D; Sañudo-Fontaneda, L A; Rodriguez-Hernandez, J

    2014-01-01

    Three different drainage systems were built in a roadside car park located on the outskirts of Oviedo (Spain): two sustainable urban drainage systems (SUDS), a swale and a filter drain; and one conventional drainage system, a concrete ditch, which is representative of the most frequently used roadside drainage system in Spain. The concentrations of pollutants were analyzed in the outflow of all three systems in order to compare their capacity to improve water quality. Physicochemical water quality parameters such as dissolved oxygen, total suspended solids, pH, electrical conductivity, turbidity and total petroleum hydrocarbons were monitored and analyzed for 25 months. Results are presented in detail showing significantly smaller amounts of outflow pollutants in SUDS than in conventional drainage systems, especially in the filter drain which provided the best performance.

  16. INVESTIGATION OF DRY-WEATHER POLLUTANT ENTRIES INTO STORM-DRAINAGE SYSTEMS

    EPA Science Inventory

    This article describes the results of a series of research tasks to develop a procedure to investigate non-stormwater (dry-weather) entries into storm drainage systems. Dry-weather flows discharging from storm drainage systems can contribute significant pollutant loadings to rece...

  17. INVESTIGATION OF INAPPROPRIATE POLLUTANTS ENTRIES INTO STORM DRAINAGE SYSTEMS: A USER'S GUIDE

    EPA Science Inventory

    This User's Guide is the result of a series of EPA sponsored research tasks to develop a procedure to investigate non-stormwater entries into storm drainage systems. A number of past projects have found that dry-weather flows discharging from storm drainage systems can contribu...

  18. Hydrodynamic model of cells for designing systems of urban groundwater drainage

    NASA Astrophysics Data System (ADS)

    Zimmermann, Eric; Riccardi, Gerardo

    2000-08-01

    An improved mathematical hydrodynamic quasi-two-dimensional model of cells, CELSUB3, is presented for simulating drainage systems that consist of pumping well fields or subsurface drains. The CELSUB3 model is composed of an assemblage of algorithms that have been developed and tested previously and that simulate saturated flow in porous media, closed conduit flow, and flow through pumping stations. A new type of link between aquifer cells and drainage conduits is proposed. This link is verified in simple problems with well known analytical solutions. The correlation between results from analytical and mathematical solutions was considered satisfactory in all cases. To simulate more complex situations, the new proposed version, CELSUB3, was applied in a project designed to control the water-table level within a sewer system in Chañar Ladeado Town, Santa Fe Province, Argentina. Alternative drainage designs, which were evaluated under conditions of dynamic recharge caused by rainfall in a critical year (wettest year for the period of record) and a typical year, are briefly described. After analyzing ten alternative designs, the best technical-economic solution is a subsurface drainage system of closed conduits with pumping stations and evacuation channels. Résumé. Un modèle hydrodynamique perfectionné de cellules en quasi 2D, CELSUB3, est présenté dans le but de simuler des systèmes de drainage qui consistent en des champs de puits de pompage ou de drains souterrains. Le modèle CELSUB3 est composé d'un assemblage d'algorithmes développés et testés précédemment et qui simulent des écoulements en milieu poreux saturé, en conduites et dans des stations de pompage. Un nouveau type de lien entre des cellules d'aquifères et des drains est proposé. Ce lien est vérifié dans des problèmes simples dont les solutions analytiques sont bien connues. La corrélation entre les résultats des solutions analytiques et des solutions mathématiques a été consid

  19. Assessment of the service performance of drainage system and transformation of pipeline network based on urban combined sewer system model.

    PubMed

    Peng, Hai-Qin; Liu, Yan; Wang, Hong-Wu; Ma, Lu-Ming

    2015-10-01

    In recent years, due to global climate change and rapid urbanization, extreme weather events occur to the city at an increasing frequency. Waterlogging is common because of heavy rains. In this case, the urban drainage system can no longer meet the original design requirements, resulting in traffic jams and even paralysis and post a threat to urban safety. Therefore, it provides a necessary foundation for urban drainage planning and design to accurately assess the capacity of the drainage system and correctly simulate the transport effect of drainage network and the carrying capacity of drainage facilities. This study adopts InfoWorks Integrated Catchment Management (ICM) to present the two combined sewer drainage systems in Yangpu District, Shanghai (China). The model can assist the design of the drainage system. Model calibration is performed based on the historical rainfall events. The calibrated model is used for the assessment of the outlet drainage and pipe loads for the storm scenario currently existing or possibly occurring in the future. The study found that the simulation and analysis results of the drainage system model were reliable. They could fully reflect the service performance of the drainage system in the study area and provide decision-making support for regional flood control and transformation of pipeline network.

  20. Adaptation Options for Land Drainage Systems Towards Sustainable Agriculture and Environment: A Czech Perspective

    NASA Astrophysics Data System (ADS)

    Kulhavý, Zbyněk; Fučík, Petr

    2015-04-01

    In this paper, issues of agricultural drainage systems are introduced and discussed from the views of their former, current and future roles and functioning in the Czech Republic (CR). A methodologically disparate survey was done on thirty-nine model localities in CR with different intensity and state of land drainage systems, aimed at description of commonly occurred problems and possible adaptations of agricultural drainage as perceived by farmers, land owners, landscape managers or by protective water management. The survey was focused on technical state of drainage, fragmentation of land ownership within drained areas as well as on possible conflicts between agricultural and environmental interests in a landscape. Achieved results confirmed that there is obviously an increasing need to reassess some functions of prevailingly single-purpose agricultural drainage systems. Drainage intensity and detected unfavourable technical state of drainage systems as well as the risks connected with the anticipated climate change from the view of possible water scarcity claims for a complex solution. An array of adaptation options for agricultural drainage systems is presented, aiming at enhancement of water retention time and improvement of water quality. It encompasses additional flow-controlling measures on tiles or ditches, or facilities for making selected parts of a drainage system inoperable in order to retain or slow down the drainage runoff, to establish water accumulation zones and to enhance water self-cleaning processes. However, it was revealed that the question of landowner parcels fragmentation on drained land in CR would dramatically complicate design and realization of these measures. Presented solutions and findings are propounded with a respect to contemporary and future state policies and international strategies for sustainable agriculture, water management and environment.

  1. Low Frequency Radio-wave System for subsurface investigation

    NASA Astrophysics Data System (ADS)

    Soldovieri, Francesco; Gennarelli, Gianluca; Kudelya, Anatoliy; Denisov, Alexander

    2015-04-01

    Low frequency radio-wave methods (RWM) allow subsurface investigations in terms of lithological structure characterization, detection of filtration flows of ground water, anthropogenic and natural cavities. In this contribution, we present a RWM that exploits two coils working at frequencies of few MHz as transmitting and receiving antennas. The basic principle of this inductive method is as follows. The primary alternating electromagnetic field radiated by the transmitting coil induces eddy currents in the subsurface mainly due to the conductivity anomalies. These eddy currents generate a secondary (scattered) magnetic field which overlaps to the incident magnetic field and is detected by the receiving coil. Despite the simple operation of the system, the complexity of the electromagnetic scattering phenomenon at hand must be properly modeled to achieve adequate performance. Therefore, an advanced data processing technique, belonging to the class of the inverse scattering approaches, has been developed by the authors in a full 3D geometry. The proposed method allows to deal with data collected on a scanning surface under a dipole inductive profiling (DIP) modality, where the transmitting/receiving coils are moved simultaneously with fixed offset (multi-bistatic configuration). The hardware, called Dipole Inductive Radio-wave System (DIRS), is composed by an electronic unit and transmitting and receiving loop antennas radiating at frequencies of few MHz (2-4 MHz), which are installed on theodolite supports. The compactness of DIRS and its robustness to external electromagnetic interference offers the possibility to perform geophysical research up to the depth of some tens of meters and under several types of ground and water surfaces, vegetation, and weather conditions. The light weight and small size of system (the single antenna with support weights about 5 kg and has a diameter of 0.5m) allows two operators to perform geophysical research without disturbing the

  2. Managing selenium-contaminated agricultural drainage water by the integrated on-farm drainage management system: role of selenium volatilization.

    PubMed

    Lin, Z Q; Cervinka, V; Pickering, I J; Zayed, A; Terry, N

    2002-07-01

    The Integrated on-Farm Drainage Management (IFDM) system was designed to dispose of selenium (Se)-contaminated agricultural irrigation drainage water through the sequential reuse of saline drainage water to grow crops having different salt tolerance. This study quantified the extent of biological volatilization in Se removal from the IFDM system located in the western San Joaquin Valley, California. Selenium volatilization from selected treatment areas, including pickleweed (Salicornia bigelovii Torr.), saltgrass (Distichlis spicata L.), bare soil, and the solar evaporator, was monitored biweekly using an open-flow sampling chamber system during the pickleweed growing season from February to September 1997, and monthly from September 1997 to January 1998. Biological volatilization from the pickleweed section removed 62.0 +/- 3.6 mg Se m(-2) y(-1) to the atmosphere, which was 5.5-fold greater than the Se accumulated in pickleweed tissues (i.e., phytoextraction). The total Se removed by volatilization from the bare soil, saltgrass, and the solar evaporator was 16.7 +/- 1.1, 4.8 +/- 0.3, and 4.3 +/- 0.9mg Se m(-2) y(-1), respectively. Selenium removal by volatilization accounted for 6.5% of the annual total Se input (957.7mg Sem(-2) y(-1)) in the pickleweed field, and about 1% of the total Se input (432.7 mg Se m(-2) y(-1)) in the solar evaporator. We concluded that Se volatilization under naturally occurring field conditions represented a relatively minor, but environmentally important pathway of Se removal from the IFDM system.

  3. Discharge characteristics of four highway drainage systems in Ohio

    USGS Publications Warehouse

    Straub, D.E.

    1995-01-01

    Excessive water in the subbase of high-way combined with large traffic volumes and heavy loads is a major cause of road deterioration. Prompt removal of any excess water in a subbase will decrease the road deterioration and extend the effective life of a highway. This study presents discharge characteristics of four highway subbase drainage systems. These systems consisted of shallow, longitudal trenches with geocomposite drain materials (edge drains made from a polyethylene core surrounded by a geotextile filter fabric) that underline the joint between the shoulder and the traffic lane of State Route 16, approximately 1.0 mile southeast of Granville, Ohio. For selected rainfall-runoff events the maximum discharge, discharge characteristics from April 1991 through November 1993 were computed for three geocomposite products- a post type, an oblong-pipe type, and a cusp type-and a conventional perforated pipe edge drain. In general, the discharge characteristics of the conventional edge drain and that of the oblong-pipe edge drain were similar for most of the rainfall-runoff event characteristics. Both produced most of the highest maximum discharges and largest discharge volumes among the four longitudal edge drains. The post edge drain produced smaller maximum discharge and volumes than the conventional and oblong-pipe edge drains, but it had the shortest lag times for most of the event characteristics. The cusp edge drain produced small maximum discharges and small volumes similar to those from the post edge drain, but it had the longest lag times of all the edge drains for most of the event characteristics. The cusp edge drain may have also had some problems during installation which could have affected the discharge characteristics.

  4. Computed tomography-anatomy of the normal feline nasolacrimal drainage system.

    PubMed

    Nöller, Claudia; Henninger, Wolfgang; Grönemeyer, Dietrich H W; Hirschberg, Ruth M; Budras, Klaus D

    2006-01-01

    Computed tomography (CT) of the nasolacrimal drainage system with and without contrast medium (barium sulfate) was used to create an anatomic basis for clinical evaluation in domestic cats. To evaluate and compare the anatomical findings, three casts were carried out and were followed by CT examinations. These CT series were also used for a three-dimensional (3D) reconstruction of the nasolacrimal drainage system within surrounding structures. In noncontrast CT images, osseous structures limiting the nasolacrimal drainage system are easily recognizable. In most cats, this allows the identification of the nasolacrimal drainage system even without contrast enhancement. A distal part of the lacrimal sac adjoins directly to the respiratory mucosa of the nasal cavity without an osseous protection. Thus, this may represent a predilection site for infiltration of adjacent pathologic processes from the nasal cavity onto the lacrimal sac. The nasolacrimal duct begins on level with the maxillary third premolar tooth. The apex of the root of the canine tooth is situated very close to the nasolacrimal duct. This close topographic relation may lead to problems with the nasolacrimal drainage system. In domestic cats the nasolacrimal drainage system consists of a descending and a horizontal part, which form an angle of approximately 90 degrees for unhindered drainage of the lacrimal fluid.

  5. DEVELOPMENT OF SRB TREATMENT SYSTEMS FOR ACID MINE DRAINAGE

    EPA Science Inventory

    Over the past decade, significant advances have been made in the development of sulfate- reducing bacteria (SRB) technology to treat acid mine drainage (AMD), Bench-scale testing, field demonstrations, and engineered applications of SRBs for the treatment of AMD will be presented...

  6. Shallow Aquifer Connectivity and Early Season Water Supply of Seasonal Wetlands and Drainages Leading to Regional Drainage Systems

    NASA Astrophysics Data System (ADS)

    McCarten, N. F.; Harter, T.

    2009-12-01

    The Sacramento and San Joaquin Rivers in the Central Valley, California are recognized being seasonally supplied by early season direct surface water runoff and later season snow melt runoff from their tributaries. In addition, early season water supply to these rivers is derived from precipitation (PPT) that has infiltrated into soils underlain by a near surface aquitard, typically at less than 2 m depth. These shallow perched groundwater systems contribute a potentially substantial amount of water from more than 500,000 hectares of landforms associated with geomorphic terraces underlain by these aquitards. Early season water input to seasonal and perennial drainages is regulated by the hydraulic conductivity of the (clay-) loamy soils and by surface and aquitard slope of the local catchments associated with these old alluvial landforms. Research on these landforms and shallow aquifers has identified a complex PPT and evapotranspiration (ET) sensitive system that includes shallow depressions that seasonally produce water table derived wetlands (“vernal pools”). These wetlands have been recognized for a very high level of plant and invertebrate species diversity including endangered species. In addition, these seasonal wetlands provide migratory feeding areas of birds. Our work on these seasonal perched systems shows that as much as 80 percent of the soil column above the aquitard is saturated, during average to high rainfall years, for up to 90 to 120 days. Where the water table of this perched system intercepts the land surface, vernal pools develop. The perched groundwater drains into seasonal surface drainages that ultimately supply the Sacramento and San Joaquin rivers. At the end of the rainy season, both the vernal pools and the perched aquifer rapidly and synchronously disappear. Once the soil is unsaturated, water flow is vertically upward due to ET. Variably saturated modeling of this system was conducted using HYDRUS 2D/3D. Climate inputs were from

  7. The Martain drainage system and the origin of valley networks and fretted channels

    NASA Astrophysics Data System (ADS)

    Carr, Michael H.

    1995-04-01

    Outflow channels provide strong evidence for abundant water near the Martian surface and an extensive groundwater system. Collapse of the surface into some channels suggests massive subsurface erosion and/or solution in addition to erosion by flow across the surface. Flat floors, steep walls, longitudinal striae and ridges, downstream deflection of striae from channel walls, and lack of river channels suggest that fretted channels form dominantly by mass wasting. A two-stage process is proposed. In the first stage, extension of valleys heads is favored by seepage of groundwater into debris shed from slopes. The debris moves downstream, aided by interstitial groundwater at the base of the debris, possibly with high pore pressures. In the second stage, because of climate change or a lower heat flow, groundwater can no longer seep into the debris flows in the valleys, their movement almost stops, and more viscous ice-lubricated debris aprons form. Almost all uplands at elevations greater than +1 km are dissected by valley networks, although the drainage densities are orders of magnitude less than is typical for the Earth. The valley networks resemble terrestrial river systems in planimetric shape, but U-shaped and rectangular-shaped cross sections, levee- like peripheral ridges, median ridges, patterns of branching and rejoining, and flat floors without river channels suggest that the networks may not be true analogs to terrestrial river valleys. It is proposed that they, like the fretted channels, formed mainly by mass wasting, aided by groundwater seepage into the mass-wasted debris. Movements of only millimeters to centimeters per year are needed to explain the channel lengths. Most valley formation ceased early at low latitudes because of progressive dehydration of the near surface, the result of sublimation of water and/or drainage of groundwater to regions of lower elevations. Valley formation persisted to later dates where aided by steep slopes, as on crater

  8. Analyzing subsurface drain network performance in an agricultural monitoring site with a three-dimensional hydrological model

    NASA Astrophysics Data System (ADS)

    Nousiainen, Riikka; Warsta, Lassi; Turunen, Mika; Huitu, Hanna; Koivusalo, Harri; Pesonen, Liisa

    2015-10-01

    Effectiveness of a subsurface drainage system decreases with time, leading to a need to restore the drainage efficiency by installing new drain pipes in problem areas. The drainage performance of the resulting system varies spatially and complicates runoff and nutrient load generation within the fields. We presented a method to estimate the drainage performance of a heterogeneous subsurface drainage system by simulating the area with the three-dimensional hydrological FLUSH model. A GIS analysis was used to delineate the surface runoff contributing area in the field. We applied the method to reproduce the water balance and to investigate the effectiveness of a subsurface drainage network of a clayey field located in southern Finland. The subsurface drainage system was originally installed in the area in 1971 and the drainage efficiency was improved in 1995 and 2005 by installing new drains. FLUSH was calibrated against total runoff and drain discharge data from 2010 to 2011 and validated against total runoff in 2012. The model supported quantification of runoff fractions via the three installed drainage networks. Model realisations were produced to investigate the extent of the runoff contributing areas and the effect of the drainage parameters on subsurface drain discharge. The analysis showed that better model performance was achieved when the efficiency of the oldest drainage network (installed in 1971) was decreased. Our analysis method can reveal the drainage system performance but not the reason for the deterioration of the drainage performance. Tillage layer runoff from the field was originally computed by subtracting drain discharge from the total runoff. The drains installed in 1995 bypass the measurement system, which renders the tillage layer runoff calculation procedure invalid after 1995. Therefore, this article suggests use of a local correction coefficient based on the simulations for further research utilizing data from the study area.

  9. Design and implementation of a new low-cost subsurface mooring system for efficient data recovery

    SciTech Connect

    Tian, Chuan; Deng, Zhiqun; Tian, Jiwei; Zhao, Wei; Song, Dalei; Xu, Ming; Xu, Xiaoyang; Lu, Jun

    2013-09-23

    Mooring systems are the most effective method for making sustained time series observations in the oceans. Generally there are two types of ocean mooring systems: surface and subsurface. Subsurface mooring system is less likely to be damaged after deployment than surface system. However, subsurface system usually needs to be retrieved from the ocean for data recovery. This paper describes the design and implementation of a new low-cost subsurface mooring system for efficient data recovery: Timed Communication Buoy System (TCBS). TCBS is usually integrated in the main float and the designated data is downloaded from the control system. After data retrieval, TCBS will separate from main float, rise up to the sea surface, and transmit data by satellite communication.

  10. Numerical evaluation of the groundwater drainage system for underground storage caverns

    NASA Astrophysics Data System (ADS)

    Park, Eui Seob; Chae, Byung Gon

    2015-04-01

    A novel concept storing cryogenic liquefied natural gas in a hard rock lined cavern has been developed and tested for several years as an alternative. In this concept, groundwater in rock mass around cavern has to be fully drained until the early stage of construction and operation to avoid possible adverse effect of groundwater near cavern. And then rock mass should be re-saturated to form an ice ring, which is the zone around cavern including ice instead of water in several joints within the frozen rock mass. The drainage system is composed of the drainage tunnel excavated beneath the cavern and drain holes drilled on rock surface of the drainage tunnel. In order to de-saturate sufficiently rock mass around the cavern, the position and horizontal spacing of drain holes should be designed efficiently. In this paper, a series of numerical study results related to the drainage system of the full-scale cavern are presented. The rock type in the study area consists mainly of banded gneiss and mica schist. Gneiss is in slightly weathered state and contains a little joint and fractures. Schist contains several well-developed schistosities that mainly stand vertically, so that vertical joints are better developed than the horizontals in the area. Lugeon tests revealed that upper aquifer and bedrock are divided in the depth of 40-50m under the surface. Groundwater level was observed in twenty monitoring wells and interpolated in the whole area. Numerical study using Visual Modflow and Seep/W has been performed to evaluate the efficiency of drainage system for underground liquefied natural gas storage cavern in two hypothetically designed layouts and determine the design parameters. In Modflow analysis, groundwater flow change in an unconfined aquifer was simulated during excavation of cavern and operation of drainage system. In Seep/W analysis, amount of seepage and drainage was also estimated in a representative vertical section of each cavern. From the results

  11. Urban drainage system planning and design--challenges with climate change and urbanization: a review.

    PubMed

    Yazdanfar, Zeinab; Sharma, Ashok

    2015-01-01

    Urban drainage systems are in general failing in their functions mainly due to non-stationary climate and rapid urbanization. As these systems are becoming less efficient, issues such as sewer overflows and increase in urban flooding leading to surge in pollutant loads to receiving water bodies are becoming pervasive rapidly. A comprehensive investigation is required to understand these factors impacting the functioning of urban drainage, which vary spatially and temporally and are more complex when weaving together. It is necessary to establish a cost-effective, integrated planning and design framework for every local area by incorporating fit for purpose alternatives. Carefully selected adaptive measures are required for the provision of sustainable drainage systems to meet combined challenges of climate change and urbanization. This paper reviews challenges associated with urban drainage systems and explores limitations and potentials of different adaptation alternatives. It is hoped that the paper would provide drainage engineers, water planners, and decision makers with the state of the art information and technologies regarding adaptation options to increase drainage systems efficiency under changing climate and urbanization.

  12. Comparison of subgaleal and subdural closed drainage system in the surgical treatment of chronic subdural hematoma

    PubMed Central

    Oral, Sukru; Borklu, Resul Emin; Kucuk, Ahmet; Ulutabanca, Halil; Selcuklu, Ahmet

    2015-01-01

    OBJECTIVE: One or two burr-hole craniostomies with subgaleal or subdural drainage system and irrigation are the most common methods for surgical treatment of CSDH. The aim of this study is to compare the advantages or disadvantages of these techniques used for CSDH. METHODS: Seventy patients were treated by burr-hole subdural drainage or subgaleal drainage system with irrigation. Our patients were classified into two groups according to the operative procedure as follows: Group I, one or two burr-hole craniostomy with subgaleal closed system drainage and irrigation (n=36), Group II, one or two burr-hole craniostomies with subdural closed drainage system and irrigation (n=38). We compared male and female ratios, complication rates, and age distribution between groups. RESULTS: There was no remarkable difference between recurrence rates of the two groups. Recurrence rate was 6.25% in Group I and 7.8% in Group II. Subdural empyema occurred in one of the patients in Group II. Symptomatic pneumocephalus did not develop in patients. Four patients were reoperated for recurrence at an average of 12–20 days after the operation with the same methods. CONCLUSION: Both of the techniques have a higher cure rate and a lower risk of recurrence. However, subgaleal drainage system is relatively less invasive, safe, and technically easy. So it is applicable for aged and higher risk patients. PMID:28058351

  13. A novel high vacuum chest drainage system – a pilot study*

    PubMed Central

    Tille, Jean-Christophe; Khabiri, Ebrahim; Giliberto, Jean-Pierre; Courvoisier, Delphine S.; Kalangos, Afksendiyos; Walpoth, Beat H.

    2014-01-01

    Aim To assess the safety and feasibility of use of a novel high vacuum chest drainage system (HVCDS) and its influence on the cardiovascular system compared to a conventional system (CCDS). Material and methods Five anesthetized pigs underwent a median sternotomy. Three drains were placed in retrocardiac, retrosternal and left pleural positions. The animals received a HVCDS (22 Fr with 180 2-mm holes, n = 2) or a CCDS (n = 2). In the fifth animal off pump coronary artery bypass graft (OPCABG) stabilizers were tested. After chest closure animals had three 30 min runs of artificial bleeding (5 ml/min) under different negative aspiration pressures (–2, –20, –40 kPa) for both groups, followed by standardized surgical bleeding (–40 kPa – HVCDS, – 2 kPa – CCDS). Hemodynamic parameters and each drain's output were registered every 5 minutes and the residual blood was assessed. All catheters, the heart and left lung underwent macroscopic and histopathological examination. Results The application of the different pressures showed neither hemodynamic changes nor differences in blood drainage with both systems in two bleeding models. The HVCDS enabled drainage comparable to the CCDS but showed relevant clotting. Application of –20 kPa and –40 kPa caused macroscopic epicardial and pulmonary lesions in all tested devices including OPCABG stabilizers consisting of sub-epicardial or sub-pleural hemorrhage without myocyte or alveolar damage. Conclusions The novel and conventional chest drainage systems used at pressures up to 40 kPa induced no hemodynamic instability. Both systems showed adequate equal drainage, despite major HVCDS clotting. High negative pressure drainage with both systems showed focal sub-epicardial and subpleural hemorrhage. Thus, long-term assessment of high pressure drainage and potential interaction with fragile structures (coronary bypass graft) should be carried out. PMID:26336441

  14. Downhole burner systems and methods for heating subsurface formations

    DOEpatents

    Farmayan, Walter Farman; Giles, Steven Paul; Brignac, Jr., Joseph Phillip; Munshi, Abdul Wahid; Abbasi, Faraz; Clomburg, Lloyd Anthony; Anderson, Karl Gregory; Tsai, Kuochen; Siddoway, Mark Alan

    2011-05-31

    A gas burner assembly for heating a subsurface formation includes an oxidant conduit, a fuel conduit, and a plurality of oxidizers coupled to the oxidant conduit. At least one of the oxidizers includes a mix chamber for mixing fuel from the fuel conduit with oxidant from the oxidant conduit, an igniter, and a shield. The shield includes a plurality of openings in communication with the oxidant conduit. At least one flame stabilizer is coupled to the shield.

  15. A Geographic Information System procedure to quantify drainage-basin characteristics

    USGS Publications Warehouse

    Eash, David A.

    1993-01-01

    The Basin Characteristics System (BCS) has been developed to quantify characteristics of a drainage basin. The first of four main BCS processing steps creates four geographic information system (GIS) digital maps representing the drainage divide, the drainage network, elevation contours, and the basin length. The drainage divide and basin length are manually digitized from 1:250,000-scale topographic maps. The drainage network is extracted using GIS software from 1:100,000-scale digital line graph data. The elevation contours are generated using GIS software from 1:250,000-scale digital elevation model data. The second and third steps use software developed to assign attributes to specific features in three of the four digital maps and analyze the four maps to quantify 24 morphometric basin characteristics. The fourth step quantifies two climatic characteristics from digitized State maps of precipitation data. Compared to manual methods of measurement, the BCS provides a reduction in the time required to quantify the 26 basin characteristics. Comparison tests indicate the BCS measurements are not significantly different from manual topographic-map measurements for 11 of 12 primary drainage-basin characteristics. Tests indicate the BCS significantly underestimates basin slope. Comparison-measurement differences for basin slope, main channel slope, and basin relief appear to be due to limitations in the digital elevation model data.

  16. The Effectiveness of the Methane Drainage of Rock-Mass with a U Ventilation System

    NASA Astrophysics Data System (ADS)

    Szlązak, Nikodem; Swolkień, Justyna

    2016-09-01

    Methane drainage is used in Polish coal mines in order to reduce mine methane emission as well as to keep methane concentration in mine workings at safe levels. The article describes the method of methane drainage used in longwall D-2 in seam 410. In Poland, coal seams are frequently mined under difficult geological conditions in the roof and in the presence of very high methane hazard. In such situations, mines usually use a system with roof caving and a U ventilation system, which means that methane is drawn off from a tail entry behind the longwall front. In this system, boreholes are drilled from a tailgate and methane is drawn off from behind longwall face. The article shows the influence of a specific ventilation system on the drainage efficiency at longwall D-2 in seam 410. At this longwall, measurements of methane emission and the efficiency of methane capture were conducted. They consisted in gauging methane concentration, air velocity, absolute air pressure and the amount of methane captured by the drainage system. Experimental data were used to estimate the variations in absolute methane-bearing capacity and ventilation methane, and - most importantly - to gauge the efficiency of methane drainage.

  17. Percutaneous Transhepatic Endobiliary Drainage of Hepatic Hydatid Cyst with Rupture into the Biliary System: An Unusual Route for Drainage

    SciTech Connect

    Inal, Mehmet; Soyupak, Suereyya; Akguel, Erol; Ezici, Hueseyin

    2002-10-15

    The most common and serious complication of hydatid cyst of the liver is rupture into the biliary tract causing obstructive jaundice, cholangitis and abscess. The traditional treatment of biliary-cystic fistula is surgery and recently endoscopic sphincterotomy. We report a case of complex heterogeneous cyst rupture into the biliary tract causing biliary obstruction in which the obstruction and cyst were treated successfully by percutaneous transhepatic endobiliary drainage. Our case is the second report of percutaneous transbiliary internal drainage of hydatid cyst with rupture into the biliary duct in which the puncture and drainage were not performed through the cyst cavity.

  18. Laboratory evaluation of zero valent iron and sulfur modified iron filter materials for agricultural drainage water treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On site filter treatment systems have the potential to remove nutrients and pesticides from agricultural subsurface drainage waters. The effectiveness and efficiency of this type of drainage water treatment will depend on the actual filter materials utilized. Two promising filter materials that coul...

  19. Location and assessment of drainage pipes beneath farm fields and golf course greens using ground penetrating radar: A research summary

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enhancing the efficiency of soil water removal, and in turn crop productivity, on farmland already containing a subsurface drainage system, typically involves installing new drain lines between the old ones. However, before this approach can be attempted, the older drainage pipes need to be located...

  20. Balance mass flux and ice velocity across the equilibrium line in drainage systems of Greenland

    NASA Astrophysics Data System (ADS)

    Zwally, H. Jay; Giovinetto, Mario B.

    2001-12-01

    Estimates of balance mass flux and depth-averaged ice velocity through the cross section aligned with the equilibrium line are produced for each of six drainage systems in Greenland. The estimates are based on a model equilibrium line fitted to field data and on a revised distribution of surface mass balance for the conterminous ice sheet. Ice drainage divides and six major drainage systems are delineated using surface topography from ERS radar altimeter data. Ice thicknesses at the equilibrium line and throughout each drainage system are based on the latest compilation of airborne radar sounding data described elsewhere. The net accumulation rate in the area bounded by the equilibrium line is 399 Gt a-1, and net ablation rate in the remaining area is 231 Gt a-1. Excluding an east central coastal ridge reduces the net accumulation rate to 397 Gt a-1, with a range from 42 to 121 Gt a-1 for the individual drainage systems. The mean balance mass flux and depth-averaged ice velocity at the cross-section aligned with the modeled equilibrium line are 0.1011 Gt km-2 a-1 and 0.111 km a-1, respectively, with little variation in these values from system to system. In contrast, the mean mass discharge per unit length along the equilibrium line ranges from one half to double the overall mean rate of 0.0468 Gt km-1 a-1. The ratio of the ice mass in the area bounded by the equilibrium line to the rate of mass output implies an effective exchange time of approximately 6 ka for total mass exchange. The range of exchange times, from a low of 3 ka in the SE drainage system to 14 ka in the NE, suggests a rank as to which regions of the ice sheet may respond more rapidly to climate fluctuations.

  1. Complex Systems Science for Subsurface Fate and Transport Report from the August 2009 Workshop

    SciTech Connect

    2010-03-01

    The subsurface environment, which encompasses the vadose and saturated zones, is a heterogeneous, geologically complex domain. Believed to contain a large percentage of Earth's biomass in the form of microorganisms, the subsurface is a dynamic zone where important biogeochemical cycles work to sustain life. Actively linked to the atmosphere and biosphere through the hydrologic and carbon cycles, the subsurface serves as a storage location for much of Earth's fresh water. Coupled hydrological, microbiological, and geochemical processes occurring within the subsurface environment cause the local and regional natural chemical fluxes that govern water quality. These processes play a vital role in the formation of soil, economically important fossil fuels, mineral deposits, and other natural resources. Cleaning up Department of Energy (DOE) lands impacted by legacy wastes and using the subsurface for carbon sequestration or nuclear waste isolation require a firm understanding of these processes and the documented means to characterize the vertical and spatial distribution of subsurface properties directing water, nutrient, and contaminant flows. This information, along with credible, predictive models that integrate hydrological, microbiological, and geochemical knowledge over a range of scales, is needed to forecast the sustainability of subsurface water systems and to devise ways to manage and manipulate dynamic in situ processes for beneficial outcomes. Predictive models provide the context for knowledge integration. They are the primary tools for forecasting the evolving geochemistry or microbial ecology of groundwater under various scenarios and for assessing and optimizing the potential effectiveness of proposed approaches to carbon sequestration, waste isolation, or environmental remediation. An iterative approach of modeling and experimentation can reveal powerful insights into the behavior of subsurface systems. State-of-science understanding codified in models

  2. Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

    DOEpatents

    Anderson, R.N.; Boulanger, A.; Bagdonas, E.P.; Xu, L.; He, W.

    1996-12-17

    The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells. 22 figs.

  3. Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

    DOEpatents

    Anderson, Roger N.; Boulanger, Albert; Bagdonas, Edward P.; Xu, Liqing; He, Wei

    1996-01-01

    The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells.

  4. Contributions of systematic tile drainage to watershed scale phosphorus transport

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) transport from agricultural fields continues be a focal point for addressing harmful algal blooms (HABs) and nuisance algae in freshwater systems throughout the world. In humid, poorly drained regions, attention has turned to P delivery through subsurface tile drainage. Research on th...

  5. Identifying weak points of urban drainage systems by means of VulNetUD.

    PubMed

    Möderl, M; Kleidorfer, M; Sitzenfrei, R; Rauch, W

    2009-01-01

    This article presents the development and application of the software tool VulNetUD. VulNetUD is a tool for GIS-based identification of vulnerable sites of urban drainage systems (UDS) using hydrodynamic simulations undertaken using EPA SWMM. The benefit of the tool is the output of different vulnerability maps rating sewer surcharging, sewer flooding, combined sewer overflow (CSO) efficiency and CSO emissions. For this, seven predefined performance indicators are used to evaluate urban drainage systems under abnormal, critical and future conditions. The application on a case study highlights the capability of the tool to identify weak points of the urban drainage systems. Thereby it is possible to identify urban drainage system components which cause the highest performance decrease across the entire system. The application of the method on a real world case study shows for instance that a reduction of catchment areas which are located upstream of CSOs with relatively less capacity in the downstream sewers achieves the highest increases efficiency of the system. Finally, the application of VulNetUD is seen as a valuable tool for managers and operators of waste water utilities to improve the efficiency of their systems. Additionally vulnerability maps generated by VulNetUD support risk management e.g. decision making in urban development planning or the development of rehabilitation strategies.

  6. Effect of subsurface drip irrigation system uniformity on cotton production in the Texas High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Planned reductions in subsurface drip irrigation (SDI) system uniformity in the semi-arid environment of West Texas could reduce installation costs. A SDI system was installed and cotton production experiment conducted from 2001 to 2006 to evaluate irrigation system water distribution uniformities h...

  7. Re-engineering the urban drainage system for resource recovery and protection of drinking water supplies.

    PubMed

    Gumbo, B

    2000-01-01

    The Harare metropolis in Zimbabwe, extending upstream from Manyame Dam in the Upper Manyame River Basin, consists of the City of Harare and its satellite towns: Chitungwiza, Norton, Epworth and Ruwa. The existing urban drainage system is typically a single-use-mixing system: water is used and discharged to "waste", excreta are flushed to sewers and eventually, after "treatment", the effluent is discharged to a drinking water supply source. Polluted urban storm water is evacuated as fast as possible. This system not only ignores the substantial value in "waste" materials, but it also exports problems to downstream communities and to vulnerable fresh-water sources. The question is how can the harare metropolis urban drainage system, which is complex and has evolved over time, be rearranged to achieve sustainability (i.e. water conservation, pollution prevention at source, protection of the vulnerable drinking water sources and recovery of valuable materials)? This paper reviews current concepts regarding the future development of the urban drainage system in line with the new vision of "Sustainable Cities of the Future". The Harare Metropolis in Zimbabwe is taken as a case, and philosophical options for re-engineering the drainage system are discussed.

  8. Utility of 222Rn as a passive tracer of subglacial distributed system drainage

    NASA Astrophysics Data System (ADS)

    Linhoff, Benjamin S.; Charette, Matthew A.; Nienow, Peter W.; Wadham, Jemma L.; Tedstone, Andrew J.; Cowton, Thomas

    2017-03-01

    Water flow beneath the Greenland Ice Sheet (GrIS) has been shown to include slow-inefficient (distributed) and fast-efficient (channelized) drainage systems, in response to meltwater delivery to the bed via both moulins and surface lake drainage. This partitioning between channelized and distributed drainage systems is difficult to quantify yet it plays an important role in bulk meltwater chemistry and glacial velocity, and thus subglacial erosion. Radon-222, which is continuously produced via the decay of 226Ra, accumulates in meltwater that has interacted with rock and sediment. Hence, elevated concentrations of 222Rn should be indicative of meltwater that has flowed through a distributed drainage system network. In the spring and summer of 2011 and 2012, we made hourly 222Rn measurements in the proglacial river of a large outlet glacier of the GrIS (Leverett Glacier, SW Greenland). Radon-222 activities were highest in the early melt season (10-15 dpm L-1), decreasing by a factor of 2-5 (3-5 dpm L-1) following the onset of widespread surface melt. Using a 222Rn mass balance model, we estimate that, on average, greater than 90% of the river 222Rn was sourced from distributed system meltwater. The distributed system 222Rn flux varied on diurnal, weekly, and seasonal time scales with highest fluxes generally occurring on the falling limb of the hydrograph and during expansion of the channelized drainage system. Using laboratory based estimates of distributed system 222Rn, the distributed system water flux generally ranged between 1-5% of the total proglacial river discharge for both seasons. This study provides a promising new method for hydrograph separation in glacial watersheds and for estimating the timing and magnitude of distributed system fluxes expelled at ice sheet margins.

  9. An initial experience with a digital drainage system during the postoperative period of pediatric thoracic surgery

    PubMed Central

    Costa, Altair da Silva; Bachichi, Thiago; Holanda, Caio; Rizzo, Luiz Augusto Lucas Martins De

    2016-01-01

    ABSTRACT Objective: To report an initial experience with a digital drainage system during the postoperative period of pediatric thoracic surgery. Methods: This was a prospective observational study involving consecutive patients, ≤ 14 years of age, treated at a pediatric thoracic surgery outpatient clinic, for whom pulmonary resection (lobectomy or segmentectomy via muscle-sparing thoracotomy) was indicated. The parameters evaluated were air leak (as quantified with the digital system), biosafety, duration of drainage, length of hospital stay, and complications. The digital system was used in 11 children (mean age, 5.9 ± 3.3 years). The mean length of hospital stay was 4.9 ± 2.6 days, the mean duration of drainage was 2.5 ± 0.7 days, and the mean drainage volume was 270.4 ± 166.7 mL. The mean maximum air leak flow was 92.78 ± 95.83 mL/min (range, 18-338 mL/min). Two patients developed postoperative complications (atelectasis and pneumonia, respectively). The use of this digital system facilitated the decision-making process during the postoperative period, reducing the risk of errors in the interpretation and management of air leaks. PMID:28117476

  10. INVESTIGATION OF INAPPROPRIATE POLLUTANT ENTRIES INTO STORM DRAINAGE SYSTEMS: A USER'S GUIDE

    EPA Science Inventory

    This User's Guide, summarized here, is the result of a series of research tasks (sponsored by the U.S. Environmental Protection Agency) to develop a procedure to investigate non-stormwater entries into storm drainage systems. Past projects have found that dry-weather flows disc...

  11. Phosphorus losses from drainage systems: breaking the surface tile riser connection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In freshwater ecosystems, phosphorus is generally the nutrient most limiting algal growth. Agricultural drainage systems in the upper Midwestern US are generally designed to drain water as quickly as possible, in order to ensure trafficability and minimize crop damage due to flooding. An unintended ...

  12. EPA Seeks Public Comments on Addition of Subsurface Intrusion Component to the Superfund Hazard Ranking System

    EPA Pesticide Factsheets

    WASHINGTON -- The U.S. Environmental Protection Agency (EPA) is seeking public comment on the proposed addition of a subsurface intrusion (SsI) component to the Superfund Hazard Ranking System (HRS). The HRS is a scoring system EPA uses to identify

  13. The Influence of Plant Root Systems on Subsurface Flow: Implications for Slope Stability

    EPA Science Inventory

    Although research has explained how plant roots mechanically stabilize soils, in this article we explore how root systems create networks of preferential flow and thus influence water pressures in soils to trigger landslides. Root systems may alter subsurface flow: Hydrological m...

  14. The Inchworm Deep Drilling System for Kilometer Scale Subsurface Exploration of Europa (IDDS)

    NASA Astrophysics Data System (ADS)

    Rafeek, S.; Gorevan, S. P.; Bartlett, P. W.; Kong, K. Y.

    2001-01-01

    The Inchworm Deep Drilling System (IDDS) is a compact subsurface transport system capable of accessing regions of astrobiological interest deep below the surface of Jupiter's moon, Europa. The IDDS answers Focus Investigation Area 1 as an innovative concept for implementing subsurface exploration of Europa. The concept is being developed at Honeybee Robotics to reach depths on the order of one kilometer with no tether or umbilical of any kind. The device's unique, inchworm-burrowing method appears capable of achieving this near-term depth goal and it is foreseeable that the IDDS will be capable of autonomously drilling to tens of kilometers below the surface. Logical applications of the concept also include accessing the proposed subsurface oceans on Ganymede and Callisto, subsurface water ice on Mars, and Lake Vostok on Earth. The conference presentation will communicate the IDDS concept and how it can enable the search for prebiotic and biotic chemical processes on Europa by bringing proper instrumentation to the subsurface ocean for in-situ investigation and/or returning samples to the surface. Currently, a proposal for breadboarding the IDDS is pending for the Research Opportunities for Space Science's Astrobiology Science and Technology Instrument Development NRA. Additional information is contained in the original extended abstract.

  15. Structural adjustment for accurate conditioning in large-scale subsurface systems

    NASA Astrophysics Data System (ADS)

    Tahmasebi, Pejman

    2017-03-01

    Most of the current subsurface simulation approaches consider a priority list for honoring the well and any other auxiliary data, and eventually adopt a middle ground between the quality of the model and conditioning it to hard data. However, as the number of datasets increases, such methods often produce undesirable features in the subsurface model. Due to their high flexibility, subsurface modeling based on training images (TIs) is becoming popular. Providing comprehensive TIs remains, however, an outstanding problem. In addition, identifying a pattern similar to those in the TI that honors the well and other conditioning data is often difficult. Moreover, the current subsurface modeling approaches do not account for small perturbations that may occur in a subsurface system. Such perturbations are active in most of the depositional systems. In this paper, a new methodology is presented that is based on an irregular gridding scheme that accounts for incomplete TIs and minor offsets. Use of the methodology enables one to use a small or incomplete TI and adaptively change the patterns in the simulation grid in order to simultaneously honor the well data and take into account the effect of the local offsets. Furthermore, the proposed method was used on various complex process-based models and their structures are deformed for matching with the conditioning point data. The accuracy and robustness of the proposed algorithm are successfully demonstrated by applying it to models of several complex examples.

  16. Calibrated Methodology for Assessing Adaptation Costs for Urban Drainage Systems

    EPA Science Inventory

    Changes in precipitation patterns associated with climate change may pose significant challenges for storm water management systems across much of the U.S. In particular, adapting these systems to more intense rainfall events will require significant investment. The assessment ...

  17. A generalised Dynamic Overflow Risk Assessment (DORA) for Real Time Control of urban drainage systems

    NASA Astrophysics Data System (ADS)

    Vezzaro, Luca; Grum, Morten

    2014-07-01

    An innovative and generalised approach to the integrated Real Time Control of urban drainage systems is presented. The Dynamic Overflow Risk Assessment (DORA) strategy aims to minimise the expected Combined Sewer Overflow (CSO) risk by considering (i) the water volume presently stored in the drainage network, (ii) the expected runoff volume (calculated by radar-based nowcast models) and - most important - (iii) the estimated uncertainty of the runoff forecasts. The inclusion of uncertainty allows for a more confident use of Real Time Control (RTC). Overflow risk is calculated by a flexible function which allows for the prioritisation of the discharge points according to their sensitivity and intended use. DORA was tested on a hypothetical example inspired by the main catchment in the city of Aarhus (Denmark). An analysis of DORA’s performance over a range of events with different return periods, using a simple conceptual model, is presented. Compared to a traditional local control approach, DORA contributed to reduce CSO volumes from the most sensitive points while reducing total CSO volumes discharged from the catchment. Additionally, the results show that the inclusion of forecasts and their uncertainty contributed to further improving the performance of drainage systems. The results of this paper will contribute to the wider usage of global RTC methods in the management of urban drainage networks.

  18. Rapid assessment system based on ecosystem services for retrofitting of sustainable drainage systems.

    PubMed

    Scholz, Miklas

    2014-01-01

    Sustainable drainage systems (SuDS) design and retrofitting is predominantly based on expert opinion supported by descriptive guidance documents. The aim of this paper is to develop an innovative rapid decision support tool based on novel ecosystem service variables for retrofitting of key SuDS techniques. This unique tool proposes the retrofitting of a SuDS technique that obtained the highest ecosystem service score for a specific urban site. This approach contrasts with methods based on traditional civil engineering judgement linked to standard variables based on community and environment studies. For a case study area (Greater Manchester), a comparison with the traditional approach of determining community and environment variables indicates that permeable pavements, filter strips, swales, ponds, constructed wetlands and below-ground storage tanks are generally less preferred than infiltration trenches, soakaways and infiltration basins. However, permeable pavements and belowground storage tanks also received relatively high scores, because of their great potential impact in terms of water quality improvement and flood control, respectively. The application of the proposed methodology will lead to changes of the sustainable drainage infrastructure in the urban landscape.

  19. Hygienic drainage for healthcare.

    PubMed

    Jennings, Peter

    2012-08-01

    Peter Jennings, technical director for ACO Building Drainage, which specialises in the development of corrosion-resistant drainage systems and building products, looks at the key issues to consider when specifying and installing pipework and drainage for hygiene-critical environments such as hospitals and other healthcare facilities.

  20. Nonlinear analysis of drainage systems to examine surface deformation: an example from Potwar Plateau (Northern Pakistan)

    NASA Astrophysics Data System (ADS)

    Shahzad, F.; Mahmood, S. A.; Gloaguen, R.

    2010-03-01

    We devise a procedure in order to characterize the relative vulnerability of the Earth's surface to tectonic deformation using the geometrical characteristics of drainage systems. The present study focuses on the nonlinear analysis of drainage networks extracted from Digital Elevation Models in order to localize areas strongly influenced by tectonics. We test this approach on the Potwar Plateau in northern Pakistan. This area is regularly affected by damaging earthquakes. Conventional studies cannot pinpoint the zones at risk, as the whole region is characterized by a sparse and diffuse seismicity. Our approach is based on the fact that rivers tend to linearize under tectonic forcing. Thus, the low fractal dimensions of the Swan, Indus and Jehlum Rivers are attributed to neotectonic activity. A detailed textural analysis is carried out to investigate the linearization, heterogeneity and connectivity of the drainage patterns. These textural aspects are quantified using the fractal dimension, as well as lacunarity and succolarity analysis. These three methods are complimentary in nature, i.e. objects with similar fractal dimensions can be distinguished further with lacunarity and/or succolarity analysis. We generate maps of fractal dimensions, lacunarity and succolarity values using a sliding window of 2.5 arc minutes by 2.5 arc minutes (2.5'×2.5'). These maps are then interpreted in terms of land surface vulnerability to tectonics. This approach allowed us to localize several zones where the drainage system is highly structurally controlled on the Potwar Plateau. The region located between Muree and Muzaffarabad is found to be prone to destructive events whereas the area westward from the Indus seems relatively unaffected. We conclude that a nonlinear analysis of the drainage system is an efficient additional tool to locate areas likely to be affected by massive destructing events affecting the Earth's surface and therefore threaten human activities.

  1. Performance assessment of a street-drainage bioretention system.

    PubMed

    Chapman, Cameron; Horner, Richard R

    2010-02-01

    Event-based, flow-paced composite sampling was carried out at the inlet and outlet of a street-side bioretention facility in Seattle, Washington, to assess its ability to reduce street runoff quantity and pollutants. Over 2.5 years, 48 to 74% of the incoming runoff was lost to infiltration and evaporation. Outlet pollutant concentrations were significantly lower than those at the inlet for nearly all monitored constituents. In terms of mass, the system retained most of the incoming pollutants. Besides soluble reactive phosphorus (the mass of which possibly increased), dissolved copper was the least effectively retained; at least 58% of dissolved copper (and potentially as much as 79%) was captured by the system. Motor oil was removed most effectively, with 92 to 96% of the incoming motor oil not leaving the system. The results indicate that bioretention systems can achieve a high level of runoff retention and treatment in real-weather conditions.

  2. A Mobile Acoustic Subsurface Sensing (MASS) System for Rapid Roadway Assessment

    PubMed Central

    Lu, Yifeng; Zhang, Yi; Cao, Yinghong; McDaniel, J. Gregory; Wang, Ming L.

    2013-01-01

    Surface waves are commonly used for vibration-based nondestructive testing for infrastructure. Spectral Analysis of Surface Waves (SASW) has been used to detect subsurface properties for geologic inspections. Recently, efforts were made to scale down these subsurface detection approaches to see how they perform on small-scale structures such as concrete slabs and pavements. Additional efforts have been made to replace the traditional surface-mounted transducers with non-contact acoustic transducers. Though some success has been achieved, most of these new approaches are inefficient because they require point-to-point measurements or off-line signal analysis. This article introduces a Mobile Acoustic Subsurface Sensing system as MASS, which is an improved surface wave based implementation for measuring the subsurface profile of roadways. The compact MASS system is a 3-wheeled cart outfitted with an electromagnetic impact source, distance register, non-contact acoustic sensors and data acquisition/processing equipment. The key advantage of the MASS system is the capability to collect measurements continuously at walking speed in an automatic way. The fast scan and real-time analysis advantages are based upon the non-contact acoustic sensing and fast air-coupled surface wave analysis program. This integration of hardware and software makes the MASS system an efficient mobile prototype for the field test. PMID:23698266

  3. Modeling and real-time control of urban drainage systems: A review

    NASA Astrophysics Data System (ADS)

    García, L.; Barreiro-Gomez, J.; Escobar, E.; Téllez, D.; Quijano, N.; Ocampo-Martinez, C.

    2015-11-01

    Urban drainage systems (UDS) may be considered large-scale systems given their large number of associated states and decision actions, making challenging their real-time control (RTC) design. Moreover, the complexity of the dynamics of the UDS makes necessary the development of strategies for the control design. This paper reviews and discusses several techniques and strategies commonly used for the control of UDS. Moreover, the models to describe, simulate, and control the transport of wastewater in UDS are also reviewed.

  4. The usefulness of Wi-Fi based digital chest drainage system in the post-operative care of pneumothorax

    PubMed Central

    Cho, Hyun Min; Hong, Yoon Joo; Byun, Chun Sung

    2016-01-01

    Background Chest drainage systems are usually composed of chest tube and underwater-seal bottle. But this conventional system may restrict patients doing exercise and give clinicians obscure data about when to remove tubes because there is no objective indicator. Recently developed digital chest drainage systems may facilitate interpretation of the grade of air leak and make it easy for clinicians to decide when to remove chest tubes. In addition, with combination of wireless internet devices, monitoring and managing of drainage system distant from the patient is possible. Methods Sixty patients of primary pneumothorax were included in a prospective randomized study and divided into two groups. Group I (study) consisted of digital chest drainage system while in group II (control), conventional underwater-seal chest bottle system was used. Data was collected from January, 2012 to September, 2013 in Eulji University Hospital, Daejeon, Korea. Results There was no difference in age, sex, smoking history and postoperative pain between two groups. But the average length of drainage was 2.2 days in group I and 3.1 days in group II (P<0.006). And more, about 90% of the patients in group I was satisfied with using new device for convenience. Conclusions Digital system was beneficial on reducing the length of tube drainage by real time monitoring. It also had advantage in portability, loudness and gave more satisfaction than conventional system. Moreover, internet based digital drainage system will be a good method in thoracic telemedicine area in the near future. PMID:27076934

  5. Subsurface sounders

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Airborne or spaceborne electromagnetic systems used to detect subsurface features are discussed. Data are given as a function of resistivity of ground material, magnetic permeability of free space, and angular frequency. It was noted that resistivities vary with the water content and temperature.

  6. An Automated, Gravity-driven CSF Drainage System Decreases Complications and Lowers Costs

    PubMed Central

    Lieberson, Robert E; Meyer, William; Trang, Tung

    2017-01-01

    Background: FlowSafeTM (BeckerSmith Medical, Irvine, CA, USA) is a novel, robotic, external lumbar drainage (ELD) system, which was designed to control cerebrospinal fluid (CSF) drainage, reduce complications, and decrease treatment costs. Methods: Forty-seven consecutive neurosurgical patients requiring ELD were treated using the FlowSafe system. Results: In 39 of 40 patients with traumatic and surgical dural openings, potential CSF leaks were avoided. In seven patients with suspected normal pressure hydrocephalus, post-infectious ventriculomegaly, or pseudotumor cerebrum, we were able to assess the likelihood of improvement with shunting. The system, therefore, produced what we considered to be the “desired result” in 46 of 47 patients (98%). Our one treatment failure (2%) involved a patient with unrecognized hydrocephalus who, following a Chiari repair with a dural patch graft, was drained for six days. A persistent CSF leak eventually required a reoperation. Two patients (4%) described low-pressure headaches during treatment. Both responded to temporarily suspending or reducing the drainage rate. We saw no complications. Required nursing interventions were minimal.  Conclusions: The FlowSafe system was safe and effective. In our experience, there were fewer complications compared to currently available ELD systems. The FlowSafe was well tolerated by our patients. The near elimination of nursing interventions should allow lumbar drainage to be delivered in less costly, non-intensive care unit settings. Larger trials will be needed. PMID:28331772

  7. Balance Mass Flux and Velocity Across the Equilibrium Line in Ice Drainage Systems of Greenland

    NASA Technical Reports Server (NTRS)

    Zwally, H. Jay; Giovinetto, Mario B.; Koblinsky, Chester J. (Technical Monitor)

    2001-01-01

    Estimates of balance mass flux and the depth-averaged ice velocity through the cross-section aligned with the equilibrium line are produced for each of six drainage systems in Greenland. (The equilibrium line, which lies at approximately 1200 m elevation on the ice sheet, is the boundary between the area of net snow accumulation at higher elevations and the areas of net melting at lower elevations around the ice sheet.) Ice drainage divides and six major drainage systems are delineated using surface topography from ERS (European Remote Sensing) radar altimeter data. The net accumulation rate in the accumulation zone bounded by the equilibrium line is 399 Gt/yr and net ablation rate in the remaining area is 231 Gt/yr. (1 GigaTon of ice is 1090 kM(exp 3). The mean balance mass flux and depth-averaged ice velocity at the cross-section aligned with the modeled equilibrium line are 0.1011 Gt kM(exp -2)/yr and 0.111 km/yr, respectively, with little variation in these values from system to system. The ratio of the ice mass above the equilibrium line to the rate of mass output implies an effective exchange time of approximately 6000 years for total mass exchange. The range of exchange times, from a low of 3 ka in the SE drainage system to 14 ka in the NE, suggests a rank as to which regions of the ice sheet may respond more rapidly to climate fluctuations.

  8. Fractal characterization of subsurface fracture network for geothermal energy extraction system

    SciTech Connect

    Watanabe; Takahashi, H.

    1993-01-28

    As a new modeling procedure of geothermal energy extraction systems, the authors present two dimensional and three dimensional modeling techniques of subsurface fracture network, based on fractal geometry. Fluid flow in fractured rock occurs primarily through a connected network of discrete fractures. The fracture network approach, therefore, seeks to model fluid flow and heat transfer through such rocks directly. Recent geophysical investigations have revealed that subsurface fracture networks can be described by "fractal geometry". In this paper, a modeling procedure of subsurface fracture network is proposed based on fractal geometry. Models of fracture networks are generated by distributing fractures randomly, following the fractal relation between fracture length r and the number of fractures N expressed with fractal dimension D as N =C·r-D, where C is a constant to signify the fracture density of the rock mass. This procedure makes it possible to characterize geothermal reservoirs by the parameters measured from field data, such as core sampling. In this characterization, the fractal dimension D and the fracture density parameter C of a geothermal reservoir are used as parameters to model the subsurface fracture network. Using this model, the transmissivities between boreholes are also obtained as a function of the fracture density parameter C, and a parameter study of system performances, such as heat extraction, is performed. The results show the dependence of thermal recovery of geothermal reservoir on fracture density parameter C.

  9. Surface water drainage system. Environmental assessment and finding of no significant impact

    SciTech Connect

    1996-05-01

    This Environmental Assessment (EA) is written pursuant to the National Environmental Policy Act (NEPA). The document identifies and evaluates the action proposed to correct deficiencies in, and then to maintain, the surface water drainage system serving the Department of Energy`s Rocky Flats Environmental Technology Site (Site), located north of Golden, Colorado. Many of the activities proposed would not normally be subject to this level of NEPA documentation. However, in many cases, maintenance of the system has been deferred to the point that wetlands vegetation has become established in some ditches and culverts, creating wetlands. The proposed activities would damage or remove some of these wetlands in order to return the drainage system to the point that it would be able to fully serve its intended function - stormwater control. The Department of Energy (DOE) regulations require that activities affecting environmentally sensitive areas like wetlands be the subject of an EA. Most portions of the surface water drainage system are presently inadequate to convey the runoff from a 100-year storm event. As a result, such an event would cause flooding across much of the Site and possibly threaten the integrity of the dams at the terminal ponds. Severe flooding would not only cause damage to facilities and equipment, but could also facilitate the transport of contaminants from individual hazardous substance sites (IHSSs). Uncontrolled flow through the A- and B-series ponds could cause contaminated sediments to become suspended and carried downstream. Additionally, high velocity flood flows significantly increase erosion losses.

  10. The co-genetic evolution of metamorphic core complexes and drainage systems

    NASA Astrophysics Data System (ADS)

    Trost, Georg; Neubauer, Franz; Robl, Jörg

    2016-04-01

    Metamorphic core complexes (MCCs) are large scale geological features that globally occur in high strain zones where rocks from lower crustal levels are rapidly exhumed along discrete fault zones, basically ductile-low-angle normal faults recognizable by a metamorphic break between the cool upper plate and hot lower plate. Standard methods, structural analysis and geochronology, are applied to reveal the geodynamic setting of MCCs and to constrain timing and rates of their exhumation. Exhumation is abundantly accompanied by spatially and temporally variable vertical (uplift) and horizontal motions (lateral advection) representing the tectonic driver of topography formation that forces drainage systems and related hillslopes to adjust. The drainage pattern commonly develops in the final stage of exhumation and contributes to the decay of the forming topography. Astonishingly, drainage systems and their characteristic metrics (e.g. normalized steepness index) in regions coined by MCCs have only been sparsely investigated to determine distinctions between different MCC-types (A- and B-type MCCs according to Le Pourhiet et al., 2012). They however, should significantly differ in their topographic expression that evolves by the interplay of tectonic forcing and erosional surface processes. A-type MCCs develop in an overall extensional regime and are bounded partly by strike-slip faults showing transtensional or transpressional components. B-type MCCs are influenced by extensional dynamics only. Here, we introduce C-type MCCs that are updoming along oversteps of crustal-scale, often orogen-parallel strike-slip shear zones. In this study, we analyze drainage systems of several prominent MCCs, and compare their drainage patterns and channel metrics to constrain their geodynamic setting. The Naxos MCC represents an A-type MCC. The Dayman Dome located in Papua New Guinea a B-type MCC, whereas MCCs of the Red River Shear Zone, the Diancang, Ailao-Shan and Day Nui Con Voi

  11. Polymers and drugs suitable for the development of a drug delivery drainage system in glaucoma surgery.

    PubMed

    Löbler, Marian; Sternberg, Katrin; Stachs, Oliver; Allemann, Reto; Grabow, Niels; Roock, Anne; Kreiner, Christine F; Streufert, Detlef; Neffe, Axel T; Hanh, Bui Duc; Lendlein, Andreas; Schmitz, Klaus-Peter; Guthoff, Rudolf

    2011-05-01

    Implantation of a glaucoma drainage system is an appropriate therapeutic intervention in some glaucoma patients. However, one drawback with this approach is the fibrotic tissue response to the implant material, leading to reduced flow of aqueous liquid or complete blockage of the drainage system. As a basis for developing an aqueous shunt we report here investigations with poly(3-hydroxybutyrate) (P(3HB)) and poly(4-hydroxybutyrate) (P(4HB)) as polymer matrices and with paclitaxel (PTX) and triamcinolone acetonide (TA) as drugs that might, in combination, delay or prevent the process of fibrosis by reducing fibroblast activity. P(3HB) and P(4HB) were fabricated into test prototypes with 500 μm outer and 200 μm inner diameter and ∼1 cm length. The antiproliferative agent PTX and the anti-inflammatory agent TA were incorporated into the polymer matrices and were released by diffusion. In vitro cell assays demonstrated that the polymers have the potential to reduce fibroblast viability, while TA showed differential inhibition of Tenon fibroblasts, but not cornea keratocytes. Implantation of polymer disks and prototype devices into rabbit eyes confirmed the good biocompatibility of the materials. The combined use of a poly(hydroxybutyrate) polymer with PTX or TA has the potential to reduce the fibrosis associated with conventional glaucoma drainage systems.

  12. Intelligent real-time operation of a pumping station for an urban drainage system

    NASA Astrophysics Data System (ADS)

    Hsu, Nien-Sheng; Huang, Chien-Lin; Wei, Chih-Chiang

    2013-05-01

    SummaryIn this study, we apply artificial intelligence techniques to the development of two real-time pumping station operation models, namely, a historical and an optimized adaptive network-based fuzzy inference system (ANFIS-His and ANFIS-Opt, respectively). The functions of these two models are the determination of the real-time operation criteria of various pumping machines for controlling flood in an urban drainage system during periods when the drainage gate is closed. The ANFIS-His is constructed from an adaptive network-based fuzzy inference system (ANFIS) using historical operation records. The ANFIS-Opt is constructed from an ANFIS using the best operation series, which are optimized by a tabu search of historical flood events. We use the Chung-Kong drainage basin, New Taipei City, Taiwan, as the study area. The operational comparison variables are the highest water level (WL) and the absolute difference between the final WL and target WL of a pumping front-pool. The results show that the ANFIS-Opt is better than the ANFIS-His and historical operation models, based on the operation simulations of two flood events using the two operation models.

  13. Agricultural Drainage Water Management in the Upper Mississippi River Basin: Potential Impact and Implementation Strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Drainage practices alter the ...

  14. A Remote Characterization System for subsurface mapping of buried waste sites

    SciTech Connect

    Sandness, G.A.; Bennett, D.W.; Martinson, L.

    1992-06-01

    This paper describes a development project that will provide new technology for characterizing hazardous waste burial sites. The project is a collaborative effort by five of the national laboratories, involving the development and demonstration of a remotely controlled site characterization system. The Remote Characterization System (RCS) includes a unique low-signature survey vehicle, a base station, radio telemetry data links, satellite-based vehicle tracking, stereo vision, and sensors for non-invasive inspection of the surface and subsurface.

  15. The role of recharge zones, discharge zones, springs and tile drainage systems in peneplains of Central European highlands with regard to water quality generation processes

    NASA Astrophysics Data System (ADS)

    Dolezal, F.; Kvitek, T.

    2003-04-01

    Large areas of ploughed lands in old peneplains of Central Europe (such as the Bohemo-Moravian Highland) are located on flat tops of hills. Their soils, mostly Cambisols on weathered acid crystalline rocks (e.g., granite and gneiss) are permeable and shallow or medium-deep. These are the zones of groundwater recharge and it is through them that the local water-bearing formations (weathered rocks, colluvia and quaternary sediments in valleys) receive their portions of nitrate and other pollutants. The groundwater exfiltrates on the lower parts of slopes and in narrow valleys, creating dispersed springs and waterlogged areas. The latter were traditionally used, if at all, as forests or meadows. Since about 1960, many of the former meadows in foothill zones of Czech highlands have been drained by subsurface tile drainage systems and turned into arable lands. Field measurements in several small experimental catchments in this area proved that the water which is being discharged into the main stream either by small surface tributaries collecting water from subsurface drainage systems or by the subsurface drainage systems themselves reveals high concentrations of nitrate. Strong intraseasonal variation of water quality and the results of runoff separation suggest that the overall turnover of groundwater is fast. It is hypothesised that the redox status of the formerly waterlogged sites has been shifted toward the oxidation side due to drainage and tillage, rendering the removal of nitrogen from groundwater by denitrification less efficient. Hence, it is mainly the combination of diffuse pollution by nitrate in the recharge zones and the lack of opportunity for denitrification in the transitional and discharge zones which makes the stream water polluted. The ploughed lands in the recharge zones represent an established basis for local agriculture and cannot be set aside. Many of them have however been declared as vulnerable zones in terms of the nitrate pollution risk

  16. Development of an in situ thermal conductivity measurement system for exploration of the shallow subsurface

    NASA Astrophysics Data System (ADS)

    Chirila, Marian Andrei; Christoph, Benjamin; Vienken, Thomas; Dietrich, Peter; Bumberger, Jan

    2016-06-01

    In this study, we attempted to develop an in situ thermal conductivity measurement system that can be used for subsurface thermal exploration. A new thermal probe was developed for mapping both the spatial and temporal variability of thermal conductivity, via direct push methods in the unconsolidated shallow subsurface. A robust, hollow cylindrical probe was constructed and its performance was tested by carrying out thermal conductivity measurements on materials with known properties. The thermal conductivity of the investigated materials can be worked out by measuring the active power consumption (in alternating current system) and temperature of the probe over fixed time intervals. A calibration method was used to eliminate any undesired thermal effects regarding the size of the probe, based on mobile thermal analyzer thermal conductivity values. Using the hollow cylindrical probe, the thermal conductivity results obtained had an error of less than 2.5% for solid samples (such as Teflon, Agar Jelly and Nylatron).

  17. Modulation of the antioxidant system in Citrus under waterlogging and subsequent drainage.

    PubMed

    Hossain, Zahed; López-Climent, María F; Arbona, Vicent; Pérez-Clemente, Rosa M; Gómez-Cadenas, Aurelio

    2009-09-01

    Soil flooding induces an impairment of the photosynthetic system that often leads to an accumulation of reactive oxygen species (ROS) in plant tissues. Moreover, flooding release by drainage can cause a sudden oxygen burst that exacerbates oxidative damage. To examine the influence of different anoxic and post-anoxic periods on citrus physiology, citrumelo CPB4475, a moderate flood-tolerant genotype, was subjected to three different periods of soil flooding followed by drainage. Plant performance in terms of visible damage, photosynthetic activity, malondialdehyde (MDA) and hydrogen peroxide accumulation was examined together with the plant antioxidant response. The results indicated that coordinated antioxidant activity, involving increased activities of superoxide dismutase (SOD) (EC 1.15.1.1) and catalase (CAT) (EC 1.11.1.6), together with a modulation of the ascorbate-glutathione cycle, allowed plants to cope with flooding-induced oxidative stress up to a certain point. Elevated ascorbate peroxidase (APX) (EC 1.11.1.11) activity or discrete increases in AsA or glutathione concentrations seemed inefficient in maintaining low levels of oxidative damage. Waterlogging stress release by soil drainage did not improve plant performance but, on the contrary, enhanced oxidative stress and even accelerated plant injury. This appears to be the result of sudden oxygen burst soon after release of water.

  18. Subsurface materials management and containment system, components thereof and methods relating thereto

    DOEpatents

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2006-04-18

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  19. An optimization model to design and manage subsurface drip irrigation system for alfalfa

    NASA Astrophysics Data System (ADS)

    Kandelous, M.; Kamai, T.; Vrugt, J. A.; Simunek, J.; Hanson, B.; Hopmans, J. W.

    2010-12-01

    Subsurface drip irrigation (SDI) is one of the most efficient and cost-effective methods for watering alfalfa plants. Lateral installation depth and distance, emitter discharge, and irrigation time and frequency of SDI, in addition to soil and climatic conditions affect alfalfa’s root water uptake and yield. Here we use a multi-objective optimization approach to find optimal SDI strategies. Our approach uses the AMALGAM evolutionary search method, in combination with the HYDRUS-2D unsaturated flow model to maximize water uptake by alfalfa’s plant roots, and minimize loss of irrigation and drainage water to the atmosphere or groundwater. We use a variety of different objective functions to analyze SDI. These criteria include the lateral installation depth and distance, the lateral discharge, irrigation duration, and irrigation frequency. Our framework includes explicit recognition of the soil moisture status during the simulation period to make sure that the top soil is dry for harvesting during the growing season. Initial results show a wide spectrum of optimized SDI strategies for different root distributions, soil textures and climate conditions. The developed tool should be useful in helping farmers optimize their irrigation strategy and design.

  20. Biosphere frontiers of subsurface life in the sedimented hydrothermal system of Guaymas Basin

    PubMed Central

    Teske, Andreas; Callaghan, Amy V.; LaRowe, Douglas E.

    2014-01-01

    Temperature is one of the key constraints on the spatial extent, physiological and phylogenetic diversity, and biogeochemical function of subsurface life. A model system to explore these interrelationships should offer a suitable range of geochemical regimes, carbon substrates and temperature gradients under which microbial life can generate energy and sustain itself. In this theory and hypothesis article, we make the case for the hydrothermally heated sediments of Guaymas Basin in the Gulf of California as a suitable model system where extensive temperature and geochemical gradients create distinct niches for active microbial populations in the hydrothermally influenced sedimentary subsurface that in turn intercept and process hydrothermally generated carbon sources. We synthesize the evidence for high-temperature microbial methane cycling and sulfate reduction at Guaymas Basin – with an eye on sulfate-dependent oxidation of abundant alkanes – and demonstrate the energetic feasibility of these latter types of deep subsurface life in previously drilled Guaymas Basin locations of Deep-Sea Drilling Project 64. PMID:25132832

  1. Reduction of acid rock drainage using steel slag in cover systems over sulfide rock waste piles.

    PubMed

    de Almeida, Rodrigo Pereira; Leite, Adilson do Lago; Borghetti Soares, Anderson

    2015-04-01

    The extraction of gold, coal, nickel, uranium, copper and other earth-moving activities almost always leads to environmental damage. In metal and coal extraction, exposure of sulfide minerals to the atmosphere leads to generation of acid rock drainage (ARD) and in underground mining to acid mine drainage (AMD) due to contamination of infiltrating groundwater. This study proposes to develop a reactive cover system that inhibits infiltration of oxygen and also releases alkalinity to increase the pH of generated ARD and attenuate metal contaminants at the same time. The reactive cover system is constructed using steel slag, a waste product generated from steel industries. This study shows that this type of cover system has the potential to reduce some of the adverse effects of sulfide mine waste disposal on land. Geochemical and geotechnical characterization tests were carried out. Different proportions of sulfide mine waste and steel slag were studied in leachate extraction tests. The best proportion was 33% of steel slag in dry weight. Other tests were conducted as follows: soil consolidation, saturated permeability and soil water characteristic curve. The cover system was numerically modeled through unsaturated flux analysis using Vadose/w. The solution proposed is an oxygen transport barrier that allows rain water percolation to treat the ARD in the waste rock pile. The results showed that the waste pile slope is an important factor and the cover system must have 5 m thickness to achieve an acceptable effectiveness.

  2. A Cloud Based Framework For Monitoring And Predicting Subsurface System Behaviour

    NASA Astrophysics Data System (ADS)

    Versteeg, R. J.; Rodzianko, A.; Johnson, D. V.; Soltanian, M. R.; Dwivedi, D.; Dafflon, B.; Tran, A. P.; Versteeg, O. J.

    2015-12-01

    Subsurface system behavior is driven and controlled by the interplay of physical, chemical, and biological processes which occur at multiple temporal and spatial scales. Capabilities to monitor, understand and predict this behavior in an effective and timely manner are needed for both scientific purposes and for effective subsurface system management. Such capabilities require three elements: Models, Data and an enabling cyberinfrastructure, which allow users to use these models and data in an effective manner. Under a DOE Office of Science funded STTR award Subsurface Insights and LBNL have designed and implemented a cloud based predictive assimilation framework (PAF) which automatically ingests, controls quality and stores heterogeneous physical and chemical subsurface data and processes these data using different inversion and modeling codes to provide information on the current state and evolution of subsurface systems. PAF is implemented as a modular cloud based software application with five components: (1) data acquisition, (2) data management, (3) data assimilation and processing, (4) visualization and result delivery and (5) orchestration. Serverside PAF uses ZF2 (a PHP web application framework) and Python and both open source (ODM2) and in house developed data models. Clientside PAF uses CSS and JS to allow for interactive data visualization and analysis. Client side modularity (which allows for a responsive interface) of the system is achieved by implementing each core capability of PAF (such as data visualization, user configuration and control, electrical geophysical monitoring and email/SMS alerts on data streams) as a SPA (Single Page Application). One of the recent enhancements is the full integration of a number of flow and mass transport and parameter estimation codes (e.g., MODFLOW, MT3DMS, PHT3D, TOUGH, PFLOTRAN) in this framework. This integration allows for autonomous and user controlled modeling of hydrological and geochemical processes. In

  3. Evaluating Potential Exposures to Ecological Receptors Due to Transport of Hydrophobic Organic Contaminants in Subsurface Systems (Final Report)

    EPA Science Inventory

    EPA's Ecological Risk Assessment Support Center (ERASC) announced the release of the final report, Evaluating Potential Exposures to Ecological Receptors Due to Transport of Hydrophobic Organic Contaminants in Subsurface Systems. This technical paper recommends several ty...

  4. Partition behaviour of alkylphenols in crude oil/brine systems under subsurface conditions

    NASA Astrophysics Data System (ADS)

    Bennett, B.; Larter, S. R.

    1997-10-01

    Partition of organic solutes between oils and water in the subsurface is an important geochemical process occurring during petroleum migration and reservoiring, during water washing, and during petroleum production. Currently no data exists on the quantitative aspects of the partition process at subsurface conditions for solutes such as phenols and aromatic hydrocarbons which are major components of both oils and waters. We have constructed an equilibration device for oils and waters based on flow injection analysis principles to measure partition coefficients of alkylphenols in crude oil/brine systems under reservoir conditions. Concentrations of C 0C 2 alkylphenols in waters and solid phase extracts of crude oils produced in the device were determined by reverse phase high performance liquid chromatography with electrochemical detection (RP-HPLC-ED), partition coefficients being measured as a function of pressure (25-340 bar), temperature (25-150°C), and water salinity (0-100,000 mg/L sodium chloride) for a variety of oils. Partition coefficients for all compounds decreased with increasing temperature, increased with water salinity and crude oil bulk NSO content, and showed little change with varying pressure. These laboratory measurements, determined under conditions close to those typically encountered in petroleum reservoirs, suggest temperature, water salinity, and crude oil bulk NSO content will have important influence on oil-water partition processes in the subsurface during migration and water washing.

  5. Some ecological mechanisms to generate habitability in planetary subsurface areas by chemolithotrophic communities: the Río Tinto subsurface ecosystem as a model system.

    PubMed

    Fernández-Remolar, David C; Gómez, Felipe; Prieto-Ballesteros, Olga; Schelble, Rachel T; Rodríguez, Nuria; Amils, Ricardo

    2008-02-01

    Chemolithotrophic communities that colonize subsurface habitats have great relevance for the astrobiological exploration of our Solar System. We hypothesize that the chemical and thermal stabilization of an environment through microbial activity could make a given planetary region habitable. The MARTE project ground-truth drilling campaigns that sampled cryptic subsurface microbial communities in the basement of the Río Tinto headwaters have shown that acidic surficial habitats are the result of the microbial oxidation of pyritic ores. The oxidation process is exothermic and releases heat under both aerobic and anaerobic conditions. These microbial communities can maintain the subsurface habitat temperature through storage heat if the subsurface temperature does not exceed their maximum growth temperature. In the acidic solutions of the Río Tinto, ferric iron acts as an effective buffer for controlling water pH. Under anaerobic conditions, ferric iron is the oxidant used by microbes to decompose pyrite through the production of sulfate, ferrous iron, and protons. The integration between the physical and chemical processes mediated by microorganisms with those driven by the local geology and hydrology have led us to hypothesize that thermal and chemical regulation mechanisms exist in this environment and that these homeostatic mechanisms could play an essential role in creating habitable areas for other types of microorganisms. Therefore, searching for the physicochemical expression of extinct and extant homeostatic mechanisms through physical and chemical anomalies in the Mars crust (i.e., local thermal gradient or high concentration of unusual products such as ferric sulfates precipitated out from acidic solutions produced by hypothetical microbial communities) could be a first step in the search for biological traces of a putative extant or extinct Mars biosphere.

  6. Some Ecological Mechanisms to Generate Habitability in Planetary Subsurface Areas by Chemolithotrophic Communities: The Ro Tinto Subsurface Ecosystem as a Model System

    NASA Astrophysics Data System (ADS)

    Fernández-Remolar, David C.; Gómez, Felipe; Prieto-Ballesteros, Olga; Schelble, Rachel T.; Rodríguez, Nuria; Amiols, Ricardo

    2008-02-01

    Chemolithotrophic communities that colonize subsurface habitats have great relevance for the astrobiological exploration of our Solar System. We hypothesize that the chemical and thermal stabilization of an environment through microbial activity could make a given planetary region habitable. The MARTE project ground-truth drilling campaigns that sampled cryptic subsurface microbial communities in the basement of the Ro Tinto headwaters have shown that acidic surficial habitats are the result of the microbial oxidation of pyritic ores. The oxidation process is exothermic and releases heat under both aerobic and anaerobic conditions. These microbial communities can maintain the subsurface habitat temperature through storage heat if the subsurface temperature does not exceed their maximum growth temperature. In the acidic solutions of the Ro Tinto, ferric iron acts as an effective buffer for controlling water pH. Under anaerobic conditions, ferric iron is the oxidant used by microbes to decompose pyrite through the production of sulfate, ferrous iron, and protons. The integration between the physical and chemical processes mediated by microorganisms with those driven by the local geology and hydrology have led us to hypothesize that thermal and chemical regulation mechanisms exist in this environment and that these homeostatic mechanisms could play an essential role in creating habitable areas for other types of microorganisms. Therefore, searching for the physicochemical expression of extinct and extant homeostatic mechanisms through physical and chemical anomalies in the Mars crust (i.e., local thermal gradient or high concentration of unusual products such as ferric sulfates precipitated out from acidic solutions produced by hypothetical microbial communities) could be a first step in the search for biological traces of a putative extant or extinct Mars biosphere.

  7. Performance of stormwater detention tanks for urban drainage systems in northern Italy.

    PubMed

    Todeschini, Sara; Papiri, Sergio; Ciaponi, Carlo

    2012-06-30

    The performance of stormwater detention tanks with alternative design configurations (insertion in the storm sewer network; volume per impervious hectare) and operating conditions (continuous and intermittent emptying rules) have been evaluated according to an integrated approach. Various performance indices have been adopted to describe the mitigation of the pollution impact to the natural environment, the reduction of the management and maintenance charges for the urban drainage system, the preservation of the normal purification efficiency, and the limitation of the costs at the treatment plant. The US EPA Storm Water Management Model has been used to simulate the rainfall-runoff process and the pollutant dynamics on theoretical catchments and storm sewer networks for an individual event, as well as for a continuous run of events and inter event periods of one year recorded at the rain gauge of Cascina Scala (Pavia, northern Italy). Also the influence of the main characteristics of the urban catchment and the drainage system (area of the catchment and slope of the network) on the performance of alternative design and operating solutions has been examined. Stormwater detention tanks combined with flow regulators demonstrated good performance with respect to environmental pollution: satisfactory performance indicators can be obtained with fairly low flow rates of flow regulators (0.5-1 L/s per hectare of impervious area) and tank volumes of about 35-50 m(3) per impervious hectare. Continuous emptying guaranteed the lowest number and duration of overflows, while an intermittent operation minimised the volume sent for purification reducing the costs and the risks of impairment in the normal treatment efficiency of the plant. Overall, simulation outcomes revealed that the performance indexes are scarcely affected by the area of the catchment and the slope of the drainage network. The result of this study represents a key issue for the implementation of

  8. Fluvial responses to late Quaternary climate change in the Shiyang River drainage system, western China

    NASA Astrophysics Data System (ADS)

    Gao, Hongshan; Li, Zongmeng; Pan, Baotian; Liu, Fenliang; Liu, Xiaopeng

    2016-04-01

    As a drainage system located in arid western China, the Shiyang River, combined with considerable fluvial strata and landform information, provides an environmental context within which to investigate fluvial responses to late Quaternary climate change. Sedimentological analysis and optically stimulated luminescence (OSL) dating enabled us to reconstruct the processes and fluvial styles of three sedimentary sequences of the Shagou and Hongshui rivers in the Shiyang drainage system. Our results present a variety of river behaviors during the late Quaternary in these areas. In the upstream Shiyang River, Zhangjiadazhuang (ZJDZ) profile of the Shagou was dominated by aggradation and a meandering channel pattern at 10.6-4.2 ka, while a noticeable channel incision occurred at ~ 4.2 ka followed by lateral channel migration. In the downstream Shiyang River, Datugou (DTG) profile of the Hongshui was an aggrading meandering river from 39.7 to 7.2 ka while channel incision occurred at 7.2 ka. Another downstream profile, Wudunwan (WDW) of the Hongshui was also characterized by aggradation from 22.4 to 4.8 ka; however, its channel pattern shifted from braided to meandering at ~ 13 ka. A discernable downcutting event occurred at ~ 4.8 ka, followed by three channel aggradation and incision episodes prior to 1.8 ka. The last 1.8 ka has been characterized by modern channel and floodplain development. The fluvial processes and styles investigated have a close correlation with late Quaternary climate change in the Shiyang River drainage. During cold phases, the WDW reach was dominated by aggradation with a braided channel pattern. During warm phases, the rivers that we investigated were also characterized by aggradation but with meandering channel patterns. Channel incision events and changes of fluvial style occurred mainly during climate transitions.

  9. Roles of dextrans on improving lymphatic drainage for liposomal drug delivery system.

    PubMed

    Feng, Linglin; Zhang, Lei; Liu, Min; Yan, Zhiqiang; Wang, Chenyu; Gu, Bing; Liu, Yu; Wei, Gang; Zhong, Gaoren; Lu, Weiyue

    2010-04-01

    Our aim was to develop a novel liposomal drug delivery system containing dextrans to reduce undesirable retention of antineoplastic agents and thus alleviate local tissue damage. At the cell level, diethylaminoethyl-dextran (DEAE-Dx) showed the strongest inhibiting effect on liposome uptake by macrophages among tested dextrans. The distribution of radiolabeled liposomes mixed with dextrans in injection site and draining lymph node was investigated in rats after subcutaneous injection. DEAE-Dx substantially reduced the undesired local retention and promoted the draining of liposome into lymphatics, which was further confirmed by confocal microscopy images revealing the substantial prevention of rhodamine B-labelled liposome sequestration by macrophages in normal lymph node in rats. Pharmacokinetic data indicated the accelerated drainage of liposome through lymphatics back to systemic circulation by mixing with DEAE-Dx. In the toxicological study in rabbits, DEAE-Dx alleviated the local tissue damage caused by liposomal doxorubicin. In conclusion, dextrans, particularly DEAE-Dx, could efficiently enhanced liposomes drainage into lymphatics, which proves themselves as promising adjuvants for lymphatic-targeted liposomal drug delivery system.

  10. An Evaluation of ENSO Asymmetry in the Community Climate System Models: A View from the Subsurface

    SciTech Connect

    Zhang, Tao; Sun, De-Zheng; Neale, Richard; Rasch, Philip J.

    2009-12-11

    The asymmetry between El Nino and La Nina is a key aspect of ENSO, and needs to be simulated well by models in order to fully capture the role of ENSO in the climate system. Here we evaluate the asymmetry between the two phases of ENSO in five successive versions of Community Climate System Model (CCSM1, CCSM2, CCSM3 at T42 resolution, CCSM3 at T85 resolution, and the latest CCSM3+NR with Neale and Richter convection scheme). Different from the previous studies, we not only examine the surface signature of ENSO asymmetry, but also its subsurface signature. We attempt to understand the causes of the ENSO asymmetry by comparing the differences among these models as well as the differences between models and the observations. An underestimate of the ENSO asymmetry is noted in all the models, but the latest version with the Neale and Richter scheme (CCSM3+NR) is getting much closer to the observations than the earlier versions. The net surface heat flux is found to damp the asymmetry in the SST field in both models and observations, but the damping effect in the models is weaker than in observations, thus excluding a role of the surface heat fluxe in contributing to the weaker asymmetry in the SST anomalies associated with ENSO. Examining the subsurface signatures of ENSO - the thermocline depth and the associated subsurface temperature for the western and eastern Pacific - reveals the same 3 bias - the asymmetry in the models is weaker than in the observations. The weaker asymmetry in the subsurface signatures in the models is related to the lack of asymmetry in the zonal wind stress over the central Pacific which is in turn due to a lack of sufficient asymmetry in deep convection (i.e., the nonlinear dependence of the deep convection on SST). CCSM3+NR has the best simulation of ENSO asymmetry among the five models. It is suggested that the better performance of CCSM3+NR is linked to an enhanced convection over the eastern Pacific during the warm phase of ENSO. An

  11. WATER DRAINAGE MODEL

    SciTech Connect

    J.B. Case

    2000-05-30

    The drainage of water from the emplacement drift is essential for the performance of the EBS. The unsaturated flow properties of the surrounding rock matrix and fractures determine how well the water will be naturally drained. To enhance natural drainage, it may be necessary to introduce engineered drainage features (e.g. drilled holes in the drifts), that will ensure communication of the flow into the fracture system. The purpose of the Water Drainage Model is to quantify and evaluate the capability of the drift to remove water naturally, using the selected conceptual repository design as a basis (CRWMS M&O, 1999d). The analysis will provide input to the Water Distribution and Removal Model of the EBS. The model is intended to be used to provide postclosure analysis of temperatures and drainage from the EBS. It has been determined that drainage from the EBS is a factor important to the postclosure safety case.

  12. Effect of alternative surface inlet designs on sediment and phosphorus drainage losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

  13. Guidelines for Design, Construction, and Evaluation of Airport Pavement Drainage

    DTIC Science & Technology

    1990-10-01

    Cedergren et. al. (11) have indicated that subsurface drainage may not be needed in pavement systems where the average annual precipitation is less...contributes water flow to each crack or joint (2). These are several ways in which the surface infiltration rate can be determined. Cedergren (3,4) has...Calculation Modules The program performs the following calculations: 5.5.7.1 Water Sources Surface infiltration (user selectable) Ridgeway procedure Cedergren

  14. Effects of tillage and application rate on atrazine transport to subsurface drainage: Evaluation of RZWQM using a six-year field study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Well-tested agricultural system models can improve our understanding of the water quality effects of management practices under different conditions. The Root Zone Water Quality Model (RZWQM) has been tested under a variety of conditions. However, the current model’s ability to simulate pesticide tr...

  15. Geochemistry of rare earth elements in a passive treatment system built for acid mine drainage remediation.

    PubMed

    Prudêncio, Maria Isabel; Valente, Teresa; Marques, Rosa; Sequeira Braga, Maria Amália; Pamplona, Jorge

    2015-11-01

    Rare earth elements (REE) were used to assess attenuation processes in a passive system for acid mine drainage treatment (Jales, Portugal). Hydrochemical parameters and REE contents in water, soils and sediments were obtained along the treatment system, after summer and winter. A decrease of REE contents in the water resulting from the interaction with limestone after summer occurs; in the wetlands REE are significantly released by the soil particles to the water. After winter, a higher water dynamics favors the AMD treatment effectiveness and performance since REE contents decrease along the system; La and Ce are preferentially sequestered by ochre sludge but released to the water in the wetlands, influencing the REE pattern of the creek water. Thus, REE fractionation occurs in the passive treatment systems and can be used as tracer to follow up and understand the geochemical processes that promote the remediation of AMD.

  16. Geomorphological analysis of the drainage system on the active convergent system in Azerbaijan, NW Iran

    NASA Astrophysics Data System (ADS)

    Kaveh Firouz, Amaneh; Burg, Jean-Pierre; Giachetta, Emanuele

    2016-04-01

    Rivers are important landforms to reconstruct recent tectonic history because they are sensitive to surface movements, especially uplift and tilting. The most important drainage basins of NW Iran are, from north to south, the Arax River, the Urmia Lake and the Ghezel Ozan River catchment. The morphology of the two adjacent catchments draining into the Caspian Sea, the Arax and Ghezel Ozan were studied to better understand the active tectonics and the effect of fault activity on morphology and erosion rate of NW Iran. We performed a quantitative analysis of channel steepness and concavity, from slope-area plots calculated from digital elevation model. This information has been combined with GPS velocity vectors and seismicity. Both catchments developed under uniform climate conditions. Results show that the two rivers are in morphological disequilibrium; they exhibit profiles with prominent convexities and knickpoints. The Arax River shows higher channel steepness and concavity index in downstream part of the profile. Distribution of knickpoints show scattered elevation between 700m and 3000m. GPS rates display shortening 10 ± 2 mma-1 and 14 ± 2 mma-1 in upstream and downstream, respectively. The river profiles of Ghezel Ozan River and its tributaries reveal more disequilibrium downstream where channel steepness and concavity index are higher than upstream. Most knickpoints occur between 1000m and 2000m. The amount of shortening by GPS measurement changes from upstream 13 ± 2 mma-1to downstream 14 ± 2 mma-1. Recorded earthquakes, such as Rudbar earthquake (Mw=7.3, 1990), are more frequent downstream. The Urmia Lake is surrounded by many small and large catchments. Only major catchments were considered for the analysis. One of the most active faults, the north Tabriz fault, corresponds to a major knickpoints on the Talkhe rud River. Concordance between river profile analysis, GPS and seismotectonic records suggests that the characteristics of the river profiles

  17. Digital reconstruction of the Song Dynasty Ganzhou drainage system based on AR technology and its’ application in the new urban area planning and revision

    NASA Astrophysics Data System (ADS)

    Cao, H. L.; Chen, Y. L.; Tao, T. H.

    2017-02-01

    Water-logging problem is a common problem in modern city. The urban built-up area of Zhangjiang new district in Ganzhou has the same water-logging problem, however, the old urban area of Ganzhou was praised as “Millennium no flood”. The drainage system of the old urban area of Ganzhou—Fushougou, which is not flooded for hundreds years because of the perfect drainage system. It’s valuable to be referenced to the modern city drainage and waterproof comprehensive planning. In order to explore the mystery of “Millennium no flood” of old urban area of Ganzhou, at the same time to provide directive opinion to the sustainability of Zhangjiang new urban area drainage system, this paper attempts to digital reconstruct the drainage system in old urban area of Ganzhou by augmented reality(AR). It will provide a new technological means and ways to evaluate the sustainability of urban underground drainage system under the surface feature changes in the landscape. On the basis of digital reconstruction of the drainage system in the old urban area of Ganzhou, the sustainability evaluation index of drainage system is studied by analyzing and contrasting with Zhangjiang new urban area drainage system, to guide the revision of comprehensive planning about city drainage and water-logging in the new urban area of Zhangjiang.

  18. Experimental validation of a sub-surface model of solar power for distributed marine sensor systems

    NASA Astrophysics Data System (ADS)

    Hahn, Gregory G.; Cantin, Heather P.; Shafer, Michael W.

    2016-04-01

    The capabilities of distributed sensor systems such as marine wildlife telemetry tags could be significantly enhanced through the integration of photovoltaic modules. Photovoltaic cells could be used to supplement the primary batteries for wildlife telemetry tags to allow for extended tag deployments, wherein larger amounts of data could be collected and transmitted in near real time. In this article, we present experimental results used to validate and improve key aspects of our original model for sub-surface solar power. We discuss the test methods and results, comparing analytic predictions to experimental results. In a previous work, we introduced a model for sub-surface solar power that used analytic models and empirical data to predict the solar irradiance available for harvest at any depth under the ocean's surface over the course of a year. This model presented underwater photovoltaic transduction as a viable means of supplementing energy for marine wildlife telemetry tags. The additional data provided by improvements in daily energy budgets would enhance the temporal and spatial comprehension of the host's activities and/or environments. Photovoltaic transduction is one method that has not been widely deployed in the sub-surface marine environments despite widespread use on terrestrial and avian species wildlife tag systems. Until now, the use of photovoltaic cells for underwater energy harvesting has generally been disregarded as a viable energy source in this arena. In addition to marine telemetry systems, photovoltaic energy harvesting systems could also serve as a means of energy supply for autonomous underwater vehicles (AUVs), as well as submersible buoys for oceanographic data collection.

  19. Analysing connectivity through landslide-channel geomorphic coupling in a large drainage system of Southern Romania

    NASA Astrophysics Data System (ADS)

    Jurchescu, Marta

    2014-05-01

    Unlike creep, splash erosion and linear erosion which sometimes are called "continuous" slope processes, since they are perceived as causing relatively continuous erosion on slopes and a rather rapid transport towards river channels, mass movement processes, excepting flows, have a discontinuous behavior, manifesting stochastically on time intervals ranging from one year to tens of years, while the displaced material can remain suspended in different parts of the slope forming sediment stores. It is obviously why estimating the sediment delivered to the river network by landslides becomes a difficult task. Landslide control on channel dynamics is just one of the several forms of hillslope-channel coupling. Landslide-channel connectivity is relevant for understanding the way landslides are contributing to the sediment flux within catchments and how their study should be integrated in the estimation of sediment budgets. This paper explores the geomorphic coupling of landslides with river channels based on an extensive landslide inventory. The study area is a large drainage basin (> 2400 km2) in southern Romania encompassing four different geomorphic units (mountains, hills, piedmont and plain). The region is highly affected by a wide range of geomorphic processes which contribute to supplying sediments to the drainage network. The presence of a reservoir at the river outlet emphasizes the importance of estimating sediment budgets, the first stage of which consists in studying sediment sources. High sediment transport is associated to flash floods, a fraction of which is due to the slope failures occurring in response to the undercutting of river channels. Nominal classification systems as well as quantitative measures available in the connectivity literature are adopted here to describe the landslides-channels contact zones. Characteristics of the geomorphic coupling interfaces are further linked to the resulting geomorphic effects of landslides on the drainage

  20. [Evaluation index system of swamp degradation in Zoige Plateau of Sichuan, Southwest China under drainage stress].

    PubMed

    Yang, Yong-Xing; Li, Kei; Yang, Yang

    2013-07-01

    The evaluation index system of swamp degradation is one of the key scientific issues in the frontier field of international wetland science research. On the basis of long-term swamp field reconnaissance, and according to the fixed position ecological investigation of plant communities and the analysis of soil samples in 20 swamp plots in three belt transects of swamp degradation research under the stress of drainage in 2009, the swamps in the Zoige Plateau of Sichuan were classified into three groups with seven swamp communities, i. e., undisturbed (A type), disturbed by long-term and weak drainage (B-D type), and disturbed by short-term and strong drainage (E-G type), according to the species importance value and by Two-Way Indicator Species Analysis (TWINSPAN). The degradation degree of the swamps was graded by the method of Principal Components Analysis (PCA), and the swamp vegetation evaluation index (SVEI) and soil evaluation index (SSEI) were developed. Based on the SVEI, the swamps were classified as pristine swamp, lightly degraded swamp, moderately degraded swamp, and severely degraded swamp. Based on the SSEI, the swamps in Hongyuan County were divided into three grades, i. e. pristine swamp, lightly degraded swamp, and severely degraded swamp, while those in Ruoergai County were divided into lightly degraded swamp, moderately degraded swamp, and severely degraded swamp. The similarity of TWINSPAN classification results and SVEI/SSEI evaluation results was above 70%, indicating that both SVEI and SSEI were effective for the swamp degradation grading, and different classification methods should be combined to comprehensively evaluate the swamps in the Plateau.

  1. Lunar and Planetary Science XXXV: Mars: Hydrology, Drainage, and Valley Systems

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The titles in this section include: 1) Analysis of Orientation Dependence of Martian Gullies; 2) A Preliminary Relationship between the Depth of Martian Gullies and the Abundance of Hydrogen on Near-Surface Mars; 3) Water Indicators in Sirenum Terra and around the Argyre Impact Basin, Mars; 4) The Distribution of Gullies and Tounge-shaped Ridges and Their Role in the Degradation of Martian Craters; 5) A Critical Evaluation of Crater Lake Systems in Memnonia Quadrangle, Mars; 6) Impact-generated Hydrothermal Activity at Gusev Crater: Implications for the Spirit Mission; 7) Characterization of the Distributary Fan in Holden NE Crater using Stereo Analysis; 8) Computational Analysis of Drainage Basins on Mars: Appraising the Drainage Density; 9) Hypsometric Analyses of Martian Basins: A Comparison to Terrestrial, Lunar, and Venusian Hypsometry; 10) Morphologic Development of Harmakhis Vallis, Mars; 11) Mangala Valles, Mars: Investigations of the source of Flood Water and Early Stages of Flooding; 12) The Formation of Aromatum Chaos and the Water Discharge Rate at Ravi Vallis; 13) Inferring Hydraulics from Geomorphology for Athabasca Valles, Mars; 14) The Origin and Evolution of Dao Vallis: Formation and Modification of Martian Channels by Structural Collapse and Glaciation; 15) Snowmelt and the Formation of Valley Networks on Martian Volcanoes; 16) Extent of Floating Ice in an Ancient Echus Chasma/Kasei Valley System, Mars.

  2. Water balance: case study of a constructed wetland as part of the bio-ecological drainage system (BIOECODS).

    PubMed

    Ayub, Khairul Rahmah; Zakaria, Nor Azazi; Abdullah, Rozi; Ramli, Rosmaliza

    2010-01-01

    The Bio-ecological Drainage System, or BIOECODS, is an urban drainage system located at the Engineering Campus, Universiti Sains Malaysia. It consists of a constructed wetland as a part of the urban drainage system to carry storm water in a closed system. In this closed system, the constructed wetland was designed particularly for further treatment of storm water. For the purpose of studying the water balance of the constructed wetland, data collection was carried out for two years (2007 and 2009). The results show that the constructed wetland has a consistent volume of water storage compared to the outflow for both years with correlation coefficients (R(2)) of 0.99 in 2007 and 0.86 in 2009.

  3. Subsurface Feature Mapping of Mars using a High Resolution Ground Penetrating Radar System

    NASA Astrophysics Data System (ADS)

    Wu, T. S.; Persaud, D. M.; Preudhomme, M. A.; Jurg, M.; Smith, M. K.; Buckley, H.; Tarnas, J.; Chalumeau, C.; Lombard-Poirot, N.; Mann, B.

    2015-12-01

    As the closest Earth-like, potentially life-sustaining planet in the solar system, Mars' future of human exploration is more a question of timing than possibility. The Martian surface remains hostile, but its subsurface geology holds promise for present or ancient astrobiology and future habitation, specifically lava tube (pyroduct) systems, whose presence has been confirmed by HiRISE imagery.The location and characterization of these systems could provide a basis for understanding the evolution of the red planet and long-term shelters for future manned missions on Mars. To detect and analyze the subsurface geology of terrestrial bodies from orbit, a novel compact (smallsat-scale) and cost-effective approach called the High-resolution Orbiter for Mapping gEology by Radar (HOMER) has been proposed. Adapting interferometry techniques with synthetic aperture radar (SAR) to a ground penetrating radar system, a small satellite constellation is able to achieve a theoretical resolution of 50m from low-Mars orbit (LMO). Alongside this initial prototype design of HOMER, proposed data processing methodology and software and a Mars mission design are presented. This project was developed as part of the 2015 NASA Ames Academy for Space Exploration.

  4. Final Environmental Assessment Airfield Storm Drainage System Repair Joint Base Andrews-Naval Air Facility Washington, MD

    DTIC Science & Technology

    2015-06-01

    heating -ventilating- cooling systems , lawn maintenance, and general maintenance of streets and sidewalks. Existing noise levels (Leq and DNL) were...effort to rehabilitate JBA facilities including runway demolition and reconstruction. Please consider using solar geothermal systems to utilize...Final Environmental Assessment Airfield Storm Drainage System Repair Joint Base Andrews–Naval Air Facility Washington, Maryland Prepared for

  5. Review of operation of urban drainage systems in cold weather: water quality considerations.

    PubMed

    Marsalek, J; Oberts, G; Exall, K; Viklander, M

    2003-01-01

    Cold climate imposes special requirements on urban drainage systems, arising from extended storage of precipitation and pollutants in the catchment snowpack, processes occurring in the snowpack, and changes in catchment surface and transport network by snow and ice. Consequently, the resulting catchment response and runoff quantity differ from those experienced in snow- and ice-free seasons. Sources of pollutants entering urban snowpacks include airborne fallout, pavement and roadside deposits, and applications of de-icing and anti-skid agents. In the snowpack, snow, water and chemicals are subject to various processes, which affect their movement through the pack and eventual release during the melting process. Soluble constituents are flushed from the snowpack early during the melt; hydrophobic substances generally stay in the pack until the very end of melt and coarse solids with adsorbed pollutants stay on the ground after the melt is finished. The impacts of snowmelt on receiving waters have been measured mostly by the snowmelt chemical composition and inferences about its environmental significance. Recently, snowmelt has been tested by standard bioassays and often found toxic. Toxicity was attributed mostly to chloride and trace metals, and contributed to reduced diversity of benthic and plant communities. Thus, snowmelt and winter runoff discharged from urban drainage threaten aquatic ecosystems in many locations and require further studies with respect to advancing their understanding and development of best management practices.

  6. Drainage Studies Using Pore-Scale Approaches

    NASA Astrophysics Data System (ADS)

    Liu, E. B.; Reed, A. H.; Hilpert, M.

    2007-12-01

    The process of drainage has wide spread applications in soil hydrology, irrigation, and the remediation of contaminants in the subsurface. In this paper, we present the comparison of experimental and pore-scale modeling results for drainage. Using a HD-500 microCT system, X-ray tomographic images (21 micron voxels) of saturation during a drainage experiment were obtained in a porous medium consisting of 20/30 mesh (590- 840 microns) Accusand. Utilizing the segmented microtomographic images of the pore space, we modeled drainage using two pore-scale approaches: (1) the pore-morphology-based simulator (PMBS) developed by Hilpert and Miller (2001), and (2) a Lattice Boltzmann (LB) model. Invasion pathways and pressure-saturation relations obtained from both the PMBS and the LB model were compared with those obtained from experiments. The results of PMBS modeling displayed good agreement with experimental observations, except at high suction and low water saturation values, where both CT resolution and model assumptions become an issue. The LB model is currently being refined, and the results of these simulations will also be presented.

  7. Passive treatment of acid mine drainage in down-flow limestone systems

    SciTech Connect

    Watzlaf, G.R.

    1997-12-31

    Passive down-flow systems, consisting of compost and/or limestone layers, may be well suited for treatment of acidic mine drainage containing ferric iron and/or aluminum. Two columns were constructed and operated in the laboratory. The first column simulated a downward, vertical-flow anaerobic wetland, also referred to as successive alkalinity-producing systems (SAPS), and has received mine drainage for 97 weeks. The 0.16-m diameter column was vertically oriented and (from bottom to top) consisted of a 0.30-m thick layer of limestone, a 0.76-m thick layer of spent mushroom compost, and 0.91 m of free standing water. Water flowed vertically downward through the system. A second column, filled with only limestone, received water from the same source as the first column. This limestone column contained a 1.06-m thick layer of limestone and 0.91 m of free standing water and has received water for 55 weeks. Actual acid mine drainage (pH = 3.1, acidity = 200 mg/L (as CaCO{sub 3}), SO{sub 4}{sup 2-} = 600 mg/L, Total Fe = 10 mg/L, Mn = 14 mg/L, and Al = 18 mg/L) was collected every two weeks from a nearby abandoned deep mine and applied to these columns at a rate of 3.8 mL/min. For the compost/limestone column, effluent pH remained above 6.2 (6.2-7.9); however, pH at a depth of 0.38 m in the compost (halfway) dropped to < 4 after 28 weeks (net acidic). At the bottom of the compost pH remained > 4.5 for all 97 weeks. Alkalinity was generated by a combination of limestone dissolution and sulfate reduction. Over the 97 week period, the column generated an average of 330 mg/L of alkalinity, mostly due to limestone dissolution. Bacterial sulfate reduction displayed an ever decreasing trend, initially accounting for more than 200 mg/L of alkalinity and after 40 weeks only accounting for about 50 mg/L.

  8. A remote characterization system for subsurface mapping of buried waste sites

    SciTech Connect

    Sandness, G.A.; Bennett, D.W.

    1992-10-01

    Mapping of buried objects and regions of chemical and radiological contamination is required at US Department of Energy (DOE) buried waste sites. The DOE Office of Technology Development Robotics Integrated Program has initiated a project to develop and demonstrate a remotely controlled subsurface sensing system, called the Remote Characterization System (RCS). This project, a collaborative effort by five of the National Laboratories, involves the development of a unique low-signature survey vehicle, a base station, radio telemetry data links, satellite-based vehicle tracking, stereo vision, and sensors for non-invasive inspection of the surface and subsurface. To minimize interference with on-board sensors, the survey vehicle has been constructed predominatantly of non-metallic materials. The vehicle is self-propelled and will be guided by an operator located at a remote base station. The RCS sensors will be environmentally sealed and internally cooled to preclude contamination during use. Ground-penetrating radar, magnetometers, and conductivity devices are planned for geophysical surveys. Chemical and radiological sensors will be provided to locate hot spots and to provide isotopic concentration data.

  9. Fate of nitrogen for subsurface drip dispersal of effluent from small wastewater systems

    NASA Astrophysics Data System (ADS)

    Beggs, R. A.; Hills, D. J.; Tchobanoglous, G.; Hopmans, J. W.

    2011-09-01

    Subsurface drip irrigation systems apply effluent from onsite wastewater systems in a more uniform manner at a lower rate than has been possible with other effluent dispersal methods. The effluent is dispersed in a biologically active part of the soil profile for optimal treatment and where the water and nutrients can be utilized by landscape plants. Container tests were performed to determine the fate of water and nitrogen compounds applied to packed loamy sand, sandy loam, and silt loam soils. Nitrogen removal rates measured in the container tests ranged from 63 to 95% despite relatively low levels of available carbon. A Hydrus 2D vadose zone model with nitrification and denitrification rate coefficients calculated as a function of soil moisture content fit the container test results reasonably well. Model results were sensitive to the denitrification rate moisture content function. Two-phase transport parameters were needed to model the preferential flow conditions in the finer soils. Applying the model to generic soil types, the greatest nitrogen losses (30 to 70%) were predicted for medium to fine texture soils and soils with restrictive layers or capillary breaks. The slow transport with subsurface drip irrigation enhanced total nitrogen losses and plant nitrogen uptake opportunity.

  10. Fate of nitrogen for subsurface drip dispersal of effluent from small wastewater systems.

    PubMed

    Beggs, R A; Hills, D J; Tchobanoglous, G; Hopmans, J W

    2011-09-25

    Subsurface drip irrigation systems apply effluent from onsite wastewater systems in a more uniform manner at a lower rate than has been possible with other effluent dispersal methods. The effluent is dispersed in a biologically active part of the soil profile for optimal treatment and where the water and nutrients can be utilized by landscape plants. Container tests were performed to determine the fate of water and nitrogen compounds applied to packed loamy sand, sandy loam, and silt loam soils. Nitrogen removal rates measured in the container tests ranged from 63 to 95% despite relatively low levels of available carbon. A Hydrus 2D vadose zone model with nitrification and denitrification rate coefficients calculated as a function of soil moisture content fit the container test results reasonably well. Model results were sensitive to the denitrification rate moisture content function. Two-phase transport parameters were needed to model the preferential flow conditions in the finer soils. Applying the model to generic soil types, the greatest nitrogen losses (30 to 70%) were predicted for medium to fine texture soils and soils with restrictive layers or capillary breaks. The slow transport with subsurface drip irrigation enhanced total nitrogen losses and plant nitrogen uptake opportunity.

  11. The impacts of climate change and urbanisation on drainage in Helsingborg, Sweden: Combined sewer system

    NASA Astrophysics Data System (ADS)

    Semadeni-Davies, Annette; Hernebring, Claes; Svensson, Gilbert; Gustafsson, Lars-Göran

    2008-02-01

    SummaryAssessment of the potential impact of climate change on water systems has been an essential part of hydrological research over the last couple of decades. However, the notion that such assessments should also include technological, demographic and land use changes is relatively recent. In this study, the potential impacts of climate change and continued urbanisation on waste and stormwater flows in the combined sewer of central Helsingborg, South Sweden, have been assessed using a series of DHI MOUSE simulations run with present conditions as well as two climate change scenarios and three progressive urbanisation storylines. At present, overflows of untreated wastewater following heavy rainfalls are a major source of pollution to the coastal receiving waters and there is a worry that increased rainfall could exacerbate the problem. Sewer flows resulting from different urbanisation storylines were simulated for two 10-year periods corresponding to present (1994-2003) and future climates (nominally 2081-2090). In all, 12 simulations were made. Climate change was simulated by altering a high-resolution rainfall record according to the climate-change signal derived from a regional climate model. Urbanisation was simulated by altering model parameters to reflect current trends in demographics and water management. It was found that city growth and projected increases in precipitation, both together and alone, are set to worsen the current drainage problems. Conversely, system renovation and installation of sustainable urban drainage systems (SUDS) has a positive effect on the urban environment in general and can largely allay the adverse impacts of both urbanisation and climate change.

  12. Fiber optic/cone penetrometer system for subsurface heavy metals detection

    SciTech Connect

    Saggese, S.; Greenwell, R.

    1995-10-01

    The objective of this project is to develop an integrated fiber optic sensor/cone penetrometer system to analyze the heavy metals content of the subsurface. This site characterization tool will use an optical fiber cable assembly which delivers high power laser energy to vaporize and excite a sample in-situ and return the emission spectrum from the plasma produced for chemical analysis. The chemical analysis technique, often referred to as laser induced breakdown spectroscopy (LIBS), has recently shown to be an effective method for the quantitative analysis of contaminants soils. By integrating the fiber optic sensor with the cone penetrometer, we anticipate that the resultant system will enable in-situ, low cost, high resolution, real-time subsurface characterization of numerous heavy metal soil contaminants simultaneously. There are several challenges associated with the integration of the LIBS sensor and cone penetrometer. One challenge is to design an effective means of optically accessing the soil via the fiber probe in the penetrometer. A second challenge is to develop the fiber probe system such that the resultant emission signal is adequate for quantitative analysis. Laboratory techniques typically use free space delivery of the laser to the sample. The high laser powers used in the laboratory cannot be used with optical fibers, therefore, the effectiveness of the LIBS system at the laser powers acceptable to fiber delivery must be evaluated. The primary objectives for this project are: (1) Establish that a fiber optic LIBS technique can be used to detect heavy metals to the required concentration levels; (2) Design and fabricate a fiber optic probe for integration with the penetrometer system for the analysis of heavy metals in soil samples; (3) Design, fabricate, and test an integrated fiber/penetrometer system; (4) Fabricate a rugged, field deployable laser source and detection hardware system; and (6) Demonstrate the prototype in field deployments.

  13. Shallow subsurface storm flow in a forested headwater catchment: Observations and modeling using a modified TOPMODEL

    USGS Publications Warehouse

    Scanlon, T.M.; Raffensperger, J.P.; Hornberger, G.M.; Clapp, R.B.

    2000-01-01

    Transient, perched water tables in the shallow subsurface are observed at the South Fork Brokenback Run catchment in Shenandoah National Park, Virginia. Crest piezometers installed along a hillslope transect show that the development of saturated conditions in the upper 1.5 m of the subsurface is controlled by total precipitation and antecedent conditions, not precipitation intensity, although soil heterogeneities strongly influence local response. The macroporous subsurface storm flow zone provides a hydrological pathway for rapid runoff generation apart from the underlying groundwater zone, a conceptualization supported by the two-storage system exhibited by hydrograph recession analysis. A modified version of TOPMODEL is used to simulate the observed catchment dynamics. In this model, generalized topographic index theory is applied to the subsurface storm flow zone to account for logarithmic storm flow recessions, indicative of linearly decreasing transmissivity with depth. Vertical drainage to the groundwater zone is required, and both subsurface reservoirs are considered to contribute to surface saturation.

  14. Carbon dioxide insufflation for chronic subdural haematoma: a simple addition to burr-hole irrigation and closed-system drainage.

    PubMed

    Kubo, S; Takimoto, H; Nakata, H; Yoshimine, T

    2003-12-01

    Burr-hole irrigation with closed-system drainage is a common surgical method used for chronic subdural haematoma. However, the subdural space with air that entered during surgery sometimes remains for a prolonged period after surgery and may hamper uncomplicated healing of the subdural space. We combined a simple procedure, insufflation of carbon dioxide (CO2) into the subdural space through a drainage catheter, with conventional burr-hole irrigation and closed-system drainage. By this additional procedure, both the subdural space and the gas within the space decreased rapidly, and the subdural drain could be removed within 24 h. By promoting obliteration of the subdural space, this simple combined technique may contribute to early recovery and discharge of patients, and to a reduction in the recurrence rate of the disease.

  15. Tile Drainage Density Reduces Groundwater Travel Times and Compromises Riparian Buffer Effectiveness.

    PubMed

    Schilling, Keith E; Wolter, Calvin F; Isenhart, Thomas M; Schultz, Richard C

    2015-11-01

    Strategies to reduce nitrate-nitrogen (nitrate) pollution delivered to streams often seek to increase groundwater residence time to achieve measureable results, yet the effects of tile drainage on residence time have not been well documented. In this study, we used a geographic information system groundwater travel time model to quantify the effects of artificial subsurface drainage on groundwater travel times in the 7443-ha Bear Creek watershed in north-central Iowa. Our objectives were to evaluate how mean groundwater travel times changed with increasing drainage intensity and to assess how tile drainage density reduces groundwater contributions to riparian buffers. Results indicate that mean groundwater travel times are reduced with increasing degrees of tile drainage. Mean groundwater travel times decreased from 5.6 to 1.1 yr, with drainage densities ranging from 0.005 m (7.6 mi) to 0.04 m (62 mi), respectively. Model simulations indicate that mean travel times with tile drainage are more than 150 times faster than those that existed before settlement. With intensive drainage, less than 2% of the groundwater in the basin appears to flow through a perennial stream buffer, thereby reducing the effectiveness of this practice to reduce stream nitrate loads. Hence, strategies, such as reconnecting tile drainage to buffers, are promising because they increase groundwater residence times in tile-drained watersheds.

  16. Decision support for sustainable urban drainage system management: a case study of Jijel, Algeria.

    PubMed

    Benzerra, Abbas; Cherrared, Marzouk; Chocat, Bernard; Cherqui, Frédéric; Zekiouk, Tarik

    2012-06-30

    This paper aims to develop a methodology to support the sustainable management of Urban Drainage Systems (UDSs) in Algeria. This research is motivated by the various difficulties that the National Sanitation Office (ONA) has in managing this complex infrastructure. The method mainly consists of two approaches: the top-down approach and the bottom-up approach. The former facilitates the identification of factors related to a sustainable UDS, the development priorities and the criteria available to managers. The latter assesses UDS performance using the weighted sum method to aggregate indicators or criteria weighted using the Analytical Hierarchy Process (AHP). The method is demonstrated through its application to the UDS in the city of Jijel, Algeria.

  17. Basal drainage system response to increasing surface melt on the Greenland ice sheet.

    PubMed

    Meierbachtol, T; Harper, J; Humphrey, N

    2013-08-16

    Surface meltwater reaching the bed of the Greenland ice sheet imparts a fundamental control on basal motion. Sliding speed depends on ice/bed coupling, dictated by the configuration and pressure of the hydrologic drainage system. In situ observations in a four-site transect containing 23 boreholes drilled to Greenland's bed reveal basal water pressures unfavorable to water-draining conduit development extending inland beneath deep ice. This finding is supported by numerical analysis based on realistic ice sheet geometry. Slow meltback of ice walls limits conduit growth, inhibiting their capacity to transport increased discharge. Key aspects of current conceptual models for Greenland basal hydrology, derived primarily from the study of mountain glaciers, appear to be limited to a portion of the ablation zone near the ice sheet margin.

  18. Evaluation of layered and mixed passive treatment systems for acid mine drainage.

    PubMed

    Jeen, Sung-Wook; Mattson, Bruce

    2016-11-01

    Laboratory column tests for passive treatment systems for mine drainage from a waste rock storage area were conducted to evaluate suitable reactive mixture, system configuration, effects of influent water chemistry, and required residence time. Five columns containing straw, chicken manure, mushroom compost, and limestone (LS), in either layered or mixed configurations, were set up to simulate the treatment system. The results showed that all of the five columns removed metals of concern (i.e. Al, Cd, Co, Cu, Fe, Ni, and Zn) with a residence time of 15 h and greater. Reaction mechanisms responsible for the removal of metals may include sulfate reduction and subsequent sulfide precipitation, precipitation of secondary carbonates and hydroxides, co-precipitation, and sorption on organic substrates and secondary precipitates. The results suggest that the mixed systems containing organic materials and LS perform better than the layered systems, sequentially treated by organic and LS layers, due to the enhanced pH adjustment, which is beneficial to bacterial activity and precipitation of secondary minerals. The column tests provide a basis for the design of a field-scale passive treatment system, such as a reducing and alkalinity producing system or a permeable reactive barrier.

  19. Impact of thawing ground on subsurface water flow and transport in a modelled permafrost system

    NASA Astrophysics Data System (ADS)

    Frampton, Andrew

    2015-04-01

    Long-term simulations representing warming temperature trends in cold regions indicate that the temporal and seasonal variability characteristics of groundwater and its discharges into surface waters is expected to decrease in a warming climate. A compelling question for waterborne transport of substances relevant for climate feedbacks, biogeochemical cycling and/or water pollution is how different scenarios of hydro-climatic change influence permafrost formation and degradation dynamics and through that also the residence times of subsurface water, from land surface recharge to surface water discharge. In this contribution, heat transport and water flow in permafrost systems which include the active layer are simulated and changes in water fluxes and associated travel times of water parcels through the subsurface are investigated. Initial results indicate that the geological setting can notably impact the spread and change in travel time distributions during warming. Also, for all cases investigated the median and minimum travel times of solute transport consistently increase, indicating longer flow pathways and greater attenuation potential as permafrost thaws. Possible related effects on carbon transport and subsequent climatic feedbacks are highlighted.

  20. Separation of drainage runoff during rainfall-runoff episodes using the stable isotope method and drainage water temperature

    NASA Astrophysics Data System (ADS)

    Zajíček, Antonín; Kvítek, Tomáš; Pomije, Tomáš

    2014-05-01

    Stabile isotopes of 2H 18O and drainage water temperature were used as natural tracers for separation rainfall-runoff event hydrograph on several tile drained catchments located in Bohemian-Moravian Highland, Czech Republic. Small agricultural catchments with drainage systems built in slopes are typical for foothill areas in the Czech and Moravian highland. Often without permanent surface runoff, the drainage systems represent an important portion of runoff and nitrogen leaching out of the catchment. The knowledge of the drainage runoff formation and the origin of its components are prerequisites for formulation of measures leading to improvement of the drainage water quality and reduction of nutrient leaching from the drained catchments. The results have proved presence of event water in the drainage runoff during rainfall-runoff events. The proportion of event water observed in the drainage runoff varied between 15 - 60 % in the summer events and 0 - 50 % in winter events, while the sudden water temperature change was between 0,1 - 4,2 °C (2 - 35 %). The comparison of isotope separation of the drainage runoff and monitoring the drainage water temperature have demonstrated that in all cases of event water detected in the runoff, a rapid change in the drainage water temperature was observed as well. The portion of event water in the runoff grows with the growing change in water temperature. Using component mixing model, it was demonstrated that water temperature can be successfully used at least as a qualitative and with some degree of inaccuracy as a quantitative tracer as well. The drawback of the non-conservative character of this tracer is compensated by both its economic and technical accessibility. The separation results also resemble results of separations at small streams. Together with a similarly high speed of the discharge reaction to beginning of precipitation, it is obvious that the mechanism of surface runoff formation and drainage runoff formation

  1. Mars penetrator: Subsurface science mission

    NASA Technical Reports Server (NTRS)

    Lumpkin, C. K.

    1974-01-01

    A penetrator system to emplace subsurface science on the planet Mars is described. The need for subsurface science is discussed, and the technologies for achieving successful atmospheric entry, Mars penetration, and data retrieval are presented.

  2. Treatment and prevention systems for acid mine drainage and halogenated contaminants

    DOEpatents

    Jin, Song [Fort Collins, CO; Fallgren, Paul H [Laramie, WY; Morris, Jeffrey M [Laramie, WY

    2012-01-31

    Embodiments include treatments for acid mine drainage generation sources (10 perhaps by injection of at least one substrate (11) and biologically constructing a protective biofilm (13) on acid mine drainage generation source materials (14). Further embodiments include treatments for degradation of contaminated water environments (17) with substrates such as returned milk and the like.

  3. Evaluation of a low-cost and accurate ocean temperature logger on subsurface mooring systems

    SciTech Connect

    Tian, Chuan; Deng, Zhiqun; Lu, Jun; Xu, Xiaoyang; Zhao, Wei; Xu, Ming

    2014-06-23

    Monitoring seawater temperature is important to understanding evolving ocean processes. To monitor internal waves or ocean mixing, a large number of temperature loggers are typically mounted on subsurface mooring systems to obtain high-resolution temperature data at different water depths. In this study, we redesigned and evaluated a compact, low-cost, self-contained, high-resolution and high-accuracy ocean temperature logger, TC-1121. The newly designed TC-1121 loggers are smaller, more robust, and their sampling intervals can be automatically changed by indicated events. They have been widely used in many mooring systems to study internal wave and ocean mixing. The logger’s fundamental design, noise analysis, calibration, drift test, and a long-term sea trial are discussed in this paper.

  4. Review of habitat classification schemes appropriate to streams, rivers, and connecting channels in the Great Lakes drainage system

    USGS Publications Warehouse

    Hudson, Patrick L.; Griffiths, R.W.; Wheaton, T.J.; Busch, W.-Dieter N.; Sly, Peter G.

    1992-01-01

    Studies of lotic classification, zonation, and distribution carried out since the turn of the century were reviewed for their use in developing a habitat classification scheme for flowing water in the Great Lakes drainage basin. Seventy papers, dealing mainly with fish but including benthos, were organized into four somewhat distinct groups. A heirarchical scale of habitat measurements is suggested, and sources of data and inventory methods, including statistical treatment, are reviewed. An outline is also provided for developing a classification system for riverine habitat in the Great Lakes drainage basin.

  5. Modelling Napl Dissolution from Lens and Pools Under Varying Flowfields in Heterogeneous Subsurface Systems

    NASA Astrophysics Data System (ADS)

    Prakash, P.; Nambi, I. M.

    2011-12-01

    Non- Aqueous Phase Liquids (NAPLs) such as chlorinated organic solvents are major sources of groundwater contamination throughout the world. The non-uniform distribution of these contaminants as NAPL pools and residual NAPL zones introduce additional spatial heterogeneity in the hydrological parameters such as porosity and permeability. Bench scale dissolution studies were carried out and a conceptual contaminant transport model was developed to predict the downstream NAPL concentrations in aqueous phase. The dissolution studies were carried out in a bench scale 2-D sand tank reactor for multiple NAPL configurations and various initial NAPL saturations. A complex heterogeneous subsurface system mimicking NAPL as residuals, NAPL as lens and NAPL as pools was created by embedding more than one NAPL contaminated zone of coarse sand within a clean NAPL free zone of fine sand. Dissolved NAPL concentrations were measured along the downstream of NAPL source zone. A 2-D conceptual contaminant transport model was developed and validated which successfully accounts for NAPL interphase mass transfer limitation under varying flow fields in a saturated heterogeneous subsurface systems. The analysis of multiple lens experimental data revealed that initial NAPL saturations and relative permeability have significant effect in altering mass transfer characteristics which affects the efficacy of any remedial effort to decontaminate groundwater. Non equilibrium concentrations of NAPL were observed near the source zone during dissolution from high initial NAPL saturations, whereas tailing concentrations with steep decline from equilibrium state were seen at later times. The rate limited conditions occurred much earlier under heterogeneous soil conditions when compared to those observed by researchers under homogeneous soil conditions. This behavior was attributed to the large changes in aqueous permeability fields occurring with the progress of dissolution process. Mathematical

  6. Minimizing contamination hazards to waterbirds using agricultural drainage evaporation ponds

    NASA Astrophysics Data System (ADS)

    Bradford, David F.; Smith, Lynda A.; Drezner, Deborah S.; Shoemaker, J. David

    1991-11-01

    In much of the San Joaquin Valley, California, USA, inadequate drainage of applied irrigation water and accumulating salts in the soil have necessitated the installation of subsurface tile drainage systems to preserve crop productivity. At present, these subsurface drainage waters are disposed of by means of evaporation ponds or discharges into the San Joaquin River. Unfortunately, most of these agricultural drainage waters contain high concentrations of salts and naturally occurring trace elements, such as selenium, and recent evidence indicates that substantial numbers of waterbirds are exposed to contamination by selenium in the evaporation ponds. In order to avoid, minimize, or mitigate the adverse impacts on wildlife using the ponds, alternative pond management methods must be identified and evaluated for implementation. A number of methods have the potential to be cost-effective in significantly reducing the contamination hazard to birds using agricultural evaporation ponds. Twenty general methods were evaluated in this study, and four methods are recommended for implementation: remove levee vegetation, remove windbreaks, deepen the ponds, and haze birds. A number of other methods are recommended for further consideration because they appear to have good prospects for reducing the contamination hazard: steepen interior levee slopes, apply herbicides and insecticides, place netting on pond shorelines, and provide freshwater habitat adjacent to evaporation ponds. It may be necessary to use a combination of methods to effectively control selenium contamination of aquatic birds because it is unlikely that a single affordable pond management method will be able to entirely eliminate the contamination hazard.

  7. Electrical Subsurface Grounding Analysis

    SciTech Connect

    J.M. Calle

    2000-11-01

    The purpose and objective of this analysis is to determine the present grounding requirements of the Exploratory Studies Facility (ESF) subsurface electrical system and to verify that the actual grounding system and devices satisfy the requirements.

  8. System analysis to estimate subsurface flow: From global level to the State of Minnesota

    USGS Publications Warehouse

    Shmagin, B.A.; Kanivetsky, R.

    2002-01-01

    Stream runoff data globally and in the state of Minnesota were used to estimate subsurface water flow. This system approach is based, in principal, on unity of groundwater and surface water systems, and it is in stark contrast to the traditional deterministic approach based on modeling. In coordination with methodology of system analysis, two levels of study were used to estimate subsurface flow. First, the global stream runoff data were assessed to estimate the temporal-spatial variability of surface water runoff. Factor analysis was used to study the temporal-spatial variability of global runoff for the period from 1918 to 1967. Results of these analysis demonstrate that the variability of global runoff could be represented by seven major components (factor scores) that could be grouped into seven distinct independent grouping from the total of 18 continental slopes on the Earth. Computed variance value in this analysis is 76% and supports such analysis. The global stream runoff for this period is stationary, and is more closely connected with the stream flow of Asia to the Pacific Ocean as well as with the stream runoff of North America towards the Arctic and Pacific Oceans. The second level examines the distribution of river runoff (annual and for February) for various landscapes and the hydrogeological conditions in the State of Minnesota (218,000 km2). The annual and minimal monthly rate of stream runoff for 115 gauging stations with a period of observation of 47 years (1935-1981) were used to characterize the spatio-temporal distribution of stream runoff in Minnesota. Results of this analysis demonstrate that the annual stream runoff rate changes from 6.3, towards 3.95, and then to 2.09 1 s-1 km-2 (the difference is significant based on Student's criteria). These values in Minnesota correspond to ecological provinces from a mixed forest province towards the broadleaf forest and to prairie province, respectively. The distribution of minimal monthly stream

  9. DEMONSTRATiON OF A SUBSURFACE CONTAINMENT SYSTEM FOR INSTALLATION AT DOE WASTE SITES

    SciTech Connect

    Thomas J. Crocker; Verna M. Carpenter

    2003-05-21

    Between 1952 and 1970, DOE buried mixed waste in pits and trenches that now have special cleanup needs. The disposal practices used decades ago left these landfills and other trenches, pits, and disposal sites filled with three million cubic meters of buried waste. This waste is becoming harmful to human safety and health. Today's cleanup and waste removal is time-consuming and expensive with some sites scheduled to complete cleanup by 2006 or later. An interim solution to the DOE buried waste problem is to encapsulate and hydraulically isolate the waste with a geomembrane barrier and monitor the performance of the barrier over its 50-yr lifetime. The installed containment barriers would isolate the buried waste and protect groundwater from pollutants until final remediations are completed. The DOE has awarded a contract to RAHCO International, Inc.; of Spokane, Washington; to design, develop, and test a novel subsurface barrier installation system, referred to as a Subsurface Containment System (SCS). The installed containment barrier consists of commercially available geomembrane materials that isolates the underground waste, similar to the way a swimming pools hold water, without disrupting hazardous material that was buried decades ago. The barrier protects soil and groundwater from contamination and effectively meets environmental cleanup standards while reducing risks, schedules, and costs. Constructing the subsurface containment barrier uses a combination of conventional and specialized equipment and a unique continuous construction process. This innovative equipment and construction method can construct a 1000-ft-long X 34-ft-wide X 30-ft-deep barrier at construction rates to 12 Wday (8 hr/day operation). Life cycle costs including RCRA cover and long-term monitoring range from approximately $380 to $590/cu yd of waste contained or $100 to $160/sq ft of placed barrier based upon the subsurface geology surrounding the waste. Project objectives for Phase I

  10. Microbiological monitoring of acid mine drainage treatment systems and aquatic surroundings using real-time PCR.

    PubMed

    Han, J S; Kim, C G

    2009-01-01

    In general, acid mine drainage (AMD) causes low pH and high metal concentrations in mining areas and surroundings. The aim of this research was to achieve microbiological monitoring for AMD and to assess whether mine water outflows have any ecological effects on the aqueous ecosystem receiving effluents from different types of treatment system. The water quality of aquatic sample was analyzed and the molecular biological diversity of the samples was assessed using 16S rRNA methods, which were implemented to determine which bacteria existed throughout various unit processes for different AMD treatment systems and their receiving water environments. Acidiphilium cryptum, a heterotrophic acidophile, was found at the AMD sites, and Rhodoferax ferrireducens, which can reduce iron using insoluble Fe(III) as an electron acceptor, was detected at many AMD treatment facilities and downstream of the treatment processes. Subsequently, quantitative real-time PCR was conducted on specific genes of selected bacteria. Surprisingly, obvious trends were observed in the relative abundance of the various bacteria that corresponded to the water quality analytical results. The copy number of Desulfosporosinus orientus, a sulfate reducing bacteria, was also observed to decrease in response to decreases in metals according to the downstream flow of the AMD treatment system.

  11. Fate of hydrocarbon pollutants in source and non-source control sustainable drainage systems.

    PubMed

    Roinas, Georgios; Mant, Cath; Williams, John B

    2014-01-01

    Sustainable drainage (SuDs) is an established method for managing runoff from developments, and source control is part of accepted design philosophy. However, there are limited studies into the contribution source control makes to pollutant removal, especially for roads. This study examines organic pollutants, total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs), in paired source and non-source control full-scale SuDs systems. Sites were selected to cover local roads, trunk roads and housing developments, with a range of SuDs, including porous asphalt, swales, detention basins and ponds. Soil and water samples were taken bi-monthly over 12 months to assess pollutant loads. Results show first flush patterns in storm events for solids, but not for TPH. The patterns of removal for specific PAHs were also different, reflecting varying physico-chemical properties. The potential of trunk roads for pollution was illustrated by peak runoff for TPH of > 17,000 μg/l. Overall there was no significant difference between pollutant loads from source and non-source control systems, but the dynamic nature of runoff means that longer-term data are required. The outcomes of this project will increase understanding of organic pollutants behaviour in SuDs. This will provide design guidance about the most appropriate systems for treating these pollutants.

  12. Role of sulfur-reducing bacteria in a wetland system treating acid mine drainage.

    PubMed

    Riefler, R Guy; Krohn, Jeremy; Stuart, Ben; Socotch, Cheryl

    2008-05-15

    This report describes a twenty month case study of a successive alkalinity producing system (SAPS) treating a strong acid mine drainage (AMD) source in Coshocton County, Ohio. Prior to the commencement of the project, a large volume of black amorphous sludge had accumulated in several of the constructed wetlands. The sludge was found to be 43% organic, with very high concentrations of sulfur, iron, aluminum, and acidity. Based on several biological, physical, and chemical analyses, the sludge was determined to be an anaerobic biofilm with a large population of sulfur-reducing bacteria and a high mineral content due to the formation of iron sulfide and aluminum precipitates. On average the system performed well, generating 26 kg CaCO3/d of alkalinity and capturing 5.0 kg/d of iron and 1.7 kg/d of aluminum. Several simple performance analysis tools were presented in this work. By comparing the pollutant influent and effluent loading, it was determined that the SAPS was performing at capacity and over the past year increased effluent concentrations were due to increased influent loadings and not system deterioration. Further, by performing a detailed cell-by-cell loading analysis of multiple chemical components, the alkalinity generated by limestone dissolution and by sulfate reduction was determined. Interestingly, 61% of the alkalinity generation in the vertical flow wetlands was due to sulfur-reducing bacteria activity, indicating that sulfur-reducing bacteria may play a more significant role in SAPS than expected.

  13. A study of subsurface wastewater infiltration systems for distributed rural sewage treatment.

    PubMed

    Qin, Wei; Dou, Junfeng; Ding, Aizhong; Xie, En; Zheng, Lei

    2014-08-01

    Three types of subsurface wastewater infiltration systems (SWIS) were developed to study the efficiency of organic pollutant removal from distributed rural sewage under various conditions. Of the three different layered substrate systems, the one with the greatest amount of decomposed cow dung (5%) and soil (DCDS) showed the highest removal efficiency with respect to total nitrogen (TN), where the others showed no significant difference. The TN removal efficiency was increased with an increasing filling height of DCDS. Compared with the TN removal efficiency of 25% in the system without DCDS, the removal efficiency of the systems in which DCDS filled half and one fourth of the height was increased by 72% and 31%, respectively. Based on seasonal variations in the discharge of the typical rural family, the SWIS were run at three different hydraulic loads of 6.5, 13 and 20 cm/d. These results illustrated that SWIS could perform well at any of the given hydraulic loads. The results of trials using different inlet configurations showed that the effluent concentration of the contaminants in the system operating a multiple-inlet mode was much lower compared with the system operated under single-inlet conditions. The effluent concentration ofa pilot-scale plant achieved the level III criteria specified by the Surface Water Quality Standard at the initial stage.

  14. Implementation of an Expert System for Design of Single-Point Subsurface Oceanographic Moorings

    DTIC Science & Technology

    1988-12-01

    POINT SUBSURFACE OCEANOGRAPHIC MOORINGS by Santhosh Kumaran and Richard A. Skop December 1988 Approved for public release. Distribution unlimited...Single-(PltSubsurface Oceanographic Moorings !Z. PERSONAL ALITHOR(S) i Santhosh Kuraran and Richard A. Skop 13a. TYPE OF REPORT 13b. TIME COVERED 1i4

  15. Paleotopographic Reconstruction of the Tharsis Magmatic Complex Reveals Potential Ancient Drainage Basin/Aquifer System

    NASA Technical Reports Server (NTRS)

    Dohm, J. M.; Ferris, J.; Anderson, R. C.; Baker, V.; Hare, T.; Barlow, N. G.; Strom, R. G.; Tanaka, K. L.; Scott, D. H.

    2001-01-01

    Paleotopographic reconstructions reveal the potential existence of an enormous Noachian drainage basin in the eastern part of the Tharsis region of significant geologic and paleohydrologic implications. Additional information is contained in the original extended abstract.

  16. Complex response of a midcontinent north America drainage system to late Wisconsinan sedimentation

    USGS Publications Warehouse

    Bettis, E. Arthur; Autin, W.J.

    1997-01-01

    The geomorphic evolution of Mud Creek basin in eastern Iowa, U.S.A. serves to illustrate how geomorphic influences such as sediment supply, valley gradient, climate, and vegetation are recorded in the alluvial stratigraphic record. Sediment supply to the fluvial system increased significantly during the late Wisconsinan through a combination of periglacial erosion and loess accumulation. Subsequent evolution of the Holocene alluvial stratigraphic record reflects long-term routing of the late Wisconsinan sediment through the drainage basin in a series of cut-and-fill cycles whose timing was influenced by hydrologic response to change in climate and vegetation. When viewed in a regional context, the alluvial stratigraphic record appears to reflect a long-term complex response of the fluvial system to increased sediment supply during the late Wisconsinan. Hydrologic and sediment-supply changes accompanying the spread of Euroamerican agriculture to the basin in the 180Os dramatically upset trends in sedimentation and channel behavior established during the Holocene. Copyright ?? 1997, SEPM (Society for Sedimentary Geology).

  17. Corrosion control when using passively treated abandoned mine drainage as alternative makeup water for cooling systems.

    PubMed

    Hsieh, Ming-Kai; Chien, Shih-Hsiang; Li, Heng; Monnell, Jason D; Dzombak, David A; Vidic, Radisav D

    2011-09-01

    Passively treated abandoned mine drainage (AMD) is a promising alternative to fresh water as power plant cooling water system makeup water in mining regions where such water is abundant. Passive treatment and reuse of AMD can avoid the contamination of surface water caused by discharge of abandoned mine water, which typically is acidic and contains high concentrations of metals, especially iron. The purpose of this study was to evaluate the feasibility of reusing passively treated AMD in cooling systems with respect to corrosion control through laboratory experiments and pilot-scale field testing. The results showed that, with the addition of the inhibitor mixture orthophosphate and tolyltriazole, mild steel and copper corrosion rates were reduced to acceptable levels (< 0.127 mm/y and < 0.0076 mm/y, respectively). Aluminum had pitting corrosion problems in every condition tested, while cupronickel showed that, even in the absence of any inhibitor and in the presence of the biocide monochloramine, its corrosion rate was still very low (0.018 mm/y).

  18. Baffled duck weed pond system for treatment of agricultural drainage water containing pharmaceuticals.

    PubMed

    Bassuney, Doaa; Tawfik, Ahmed

    2017-02-03

    The aim of the study is to assess the efficiency of a novel bioremediation system namely baffled duck weed pond (BDWP) system for treatment of agricultural drainage water containing pharmaceuticals at different hydraulic retention times (HRTs). The removal efficiencies of acetaminophen (ACT), amoxicillin (AMX) and ampicillin (AMP) increased from 69.3±8.6 to 87.3 ±3.5%, from 52.9±9.4 to 82.9±5.2% and from 55.3±7.9 to 90.6±2.8% at increasing the HRT from 6 to 8 d., respectively. However, ACT, AMX and AMP removal efficiencies were slightly improved at increasing the HRT from 8 to 12 d. Diclofenac (DFC) removal efficiencies amounted to 56.6 ±11.6, 55.7±11.9 and 28.3 ±12.9% at an HRTs of 12, 8 and 6d., respectively. The results showed no relationship between the uptake / absorption of pharmaceuticals fractions and BOD5/COD ratio except ACT where R(2) was 0.84. The effect of COD/ N ratio on the removal efficiency of pharmaceuticals fractions was slight. Additional removal of pharmaceuticals fractions and nitrification was occurred in carrier sponge media situated in the last compartment of the BDWP.

  19. A Tower-based Prototype VHF/UHF Radar for Subsurface Sensing: System Description and Data Inversion Results

    NASA Technical Reports Server (NTRS)

    Moghaddam, Mahta; Pierce, Leland; Tabatabaeenejad, Alireza; Rodriguez, Ernesto

    2005-01-01

    Knowledge of subsurface characteristics such as permittivity variations and layering structure could provide a breakthrough in many terrestrial and planetary science disciplines. For Earth science, knowledge of subsurface and subcanopy soil moisture layers can enable the estimation of vertical flow in the soil column linking surface hydrologic processes with that in the subsurface. For planetary science, determining the existence of subsurface water and ice is regarded as one of the most critical information needs for the study of the origins of the solar system. The subsurface in general can be described as several near-parallel layers with rough interfaces. Each homogenous rough layer can be defined by its average thickness, permittivity, and rms interface roughness assuming a known surface spectral distribution. As the number and depth of layers increase, the number of measurements needed to invert for the layer unknowns also increases, and deeper penetration capability would be required. To nondestructively calculate the characteristics of the rough layers, a multifrequency polarimetric radar backscattering approach can be used. One such system is that we have developed for data prototyping of the Microwave Observatory of Subcanopy and Subsurface (MOSS) mission concept. A tower-mounted radar makes backscattering measurements at VHF, UHF, and L-band frequencies. The radar is a pulsed CW system, which uses the same wideband antenna to transmit and receive the signals at all three frequencies. To focus the beam at various incidence angles within the beamwidth of the antenna, the tower is moved vertically and measurements made at each position. The signals are coherently summed to achieve focusing and image formation in the subsurface. This requires an estimate of wave velocity profiles. To solve the inverse scattering problem for subsurface velocity profile simultaneously with radar focusing, we use an iterative technique based on a forward numerical solution of

  20. Foam drainage

    SciTech Connect

    Kraynik, A.M.

    1983-11-01

    Transient drainage from a column of persistent foam has been analyzed theoretically. Gravity-driven flow was assumed to occur through an interconnected network of Plateau borders that define the edges of foam cells taken to be regular pentagonal dodecahedrons. A small liquid volume fraction and monodisperse cell size distribution were assumed. In the basic model, it is assumed that all liquid is contained in Plateau borders that are bounded by rigid gas-liquid interfaces. The predicted half life, the time required for one half of the liquid to drain from the foam, is inversely proportional to the square of the cell diameter, illustrating the importance of foam structure in drainage. Liquid hold up in the films separating adjacent cells, nonuniform initial liquid volume fraction distribution and interfacial mobility are explored. Border suction due to reduced pressure in the Plateau borders provides a mechanism for film drainage. Simultaneous film drainage and flow through the Plateau borders are analyzed. Sufficient conditions for neglecting film drainage kinetics are obtained. The results indicate that improved foam stability is related to small cells, liquid hold up in the films and slow film drainage kinetics.

  1. Root system stabilization of sugarcane fertigated by subsurface drip using a minirhizotron

    NASA Astrophysics Data System (ADS)

    Yukitaka Pessinatti Ohashi, Augusto; Célia de Matos Pires, Regina; Barros de Oliveira Silva, Andre Luiz; Vasconcelos Ribeiro, Rafael

    2013-04-01

    To improve the efficiency of water use in irrigation practices and to provide information for modeling the knowledge of plants root system becomes necessary. The use of subsurface drip irrigation (SDI) in sugarcane cultivation is an interesting cultural practice to improve production and allow cultivation in marginal lands due to water deficits conditions. The SDI provides better water use efficiency, due to the water and nutrients application in root zone plants. However, despite of the agronomic importance, few studies about the root system of sugarcane were performed. The use of root scanner is an alternative to the evaluation of the root system, which enables the continuous study of the roots throughout the cycle and for many years, but data about the use of this method for sugarcane are still scarce. The aim of this study was to determine the time required for stabilization of the root system growth of sugarcane cultivar IACSP-5000 around the access tube in which images were captured. The field experiment was carried out in Campinas, São Paulo State, Brazil. The fertigation was applied by a subsurface drip system.. The soil moisture was monitored by capacitance probes. The pH and electrical conductivity of the soil solution were monitored through solution extractor. Two access tubes with 1.05 m length were used, with 7 days difference between installations. The images were captured at 110, 128, 136, 143 and 151 days after harvest cane-plant, in the second cycle (1st cane ratoon), with the Root Scanner CI-600 ™ and were analyzed the number of roots and root length in each layer in different depths in the soil profile by software RootSnap! ™. The results show that the highest rates of increase in the number and length of roots were observed in the first 27 days. Absolute growth rates of up to 81 mm day-1 and 38 mm day-1 were presented in 0-20 and 20-40 cm layer respectively. The number of roots stabilized from 27 days after installation of the tube, while

  2. Can subsurface drip irrigation (SDI) be a competitive irrigation system in the Great Plains region for commodity crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface drip irrigation (SDI) as with all microirrigation systems is typically only used on crops with greater value. In the U.S. Great Plains region, the typical irrigated crops are the cereal and oil seed crops and cotton. These crops have less economic revenue than typical microirrigated cro...

  3. Subsurface storage of liquids in the Floridan aquifer system in south Florida

    USGS Publications Warehouse

    Meyer, Frederick W.

    1989-01-01

    The Floridan aquifer system in south Florida is composed chiefly of carbonate rocks that range in age from early Miocene to Paleocene. The top of the Floridian aquifer system generally occurs at depths ranging from 500 to 1,000 ft, and the average thickness is about 3,000 ft. It is divided into three general hydrogeologic units that include Upper Floridan aquifer, the middle confining unit, and the Lower Floridan aquifer. Groundwater movement in the Upper Floridan aquifer is generally from the area of highest head in central Florida, eastward to the Straits of Florida, westward to the Gulf of Mexico, and, to a much lesser extent, southward. Injection of nontoxic liquid wastes into deep, saline parts of the Floridan aquifer system as a pollution-control measure began in 1943 with injection of oilfield brine in southwest Florida. Since then, the practice has quickly expanded, and many high capacity municipal and industrial injection wells are now in operation in southeast Florida. The principal use of the Floridan aquifer system in south Florida is for subsurface storage of liquid waste. The Boulder Zone of the Lower Floridan aquifer is extensively used as a receptacle for injected treated municipal wastewater, oilfield brine and, to a lesser extent, industrial wastewater. Pilot studies indicate a potential for cyclic storage of freshwater in the Upper Floridan aquifer in south Florida. (USGS)

  4. Integration of the Gila River drainage system through the Basin and Range province of southern Arizona and southwestern New Mexico (USA)

    NASA Astrophysics Data System (ADS)

    Dickinson, William R.

    2015-05-01

    The Gila River and its tributaries in southern Arizona and adjoining states incorporate several dozen individual extensional basins of the central Basin and Range province into a single integrated drainage network. Forty basins in the Gila domain contain more than 1000 m (maximum ~ 3500 m) of post-12 Ma basin fill. Subsurface evaporites in many basins document internal drainages terminating in isolated playa lakes during early phases of basin history. The nature of intrabasinal and interbasinal divides and of eroded or sedimented stream passages through mountain ranges intervening between the basins reveal the geomorphic mechanisms that achieved drainage integration over late Miocene to early Pleistocene time. Drainage integration accompanied by headward erosion eastward toward Gila headwaters was a response to Miocene opening of the Gulf of California, into which the Gila River debouched directly before the Pliocene (< 5 Ma) lower course of the Colorado River was established. Residual basins of internal drainage where headward erosion has not yet penetrated into basin fill are most common in the easternmost Gila domain but also persist locally farther west. Most basin fill was dissected during drainage integration within the upstream Gila domain but continued accumulation of undissected basin fill by sediment aggradation is dominant in the downstream Gila domain. Basin dissection was initiated by Pliocene time in the central Gila domain but was delayed until Pleistocene time farther east. In the westernmost Gila domain, interaction with erosional and depositional episodes along the Colorado River influenced the development of Quaternary landscapes along the tributary Gila River. The sedimentary history of the Gila drainage network illustrates the means by which trunk rivers can establish courses across corrugated topography produced by the extensional rupture of continental blocks.

  5. Characterization of Manganese Oxide Precipitates from Appalachian Coal Mine Mine Drainage Treatment Systems

    SciTech Connect

    Tan, H.; Zhang, G; Heaney, P; Webb, S; Burgos, W

    2010-01-01

    The removal of Mn(II) from coal mine drainage (CMD) by chemical addition/active treatment can significantly increase treatment costs. Passive treatment for Mn removal involves promotion of biological oxidative precipitation of manganese oxides (MnO{sub x}). Manganese(II) removal was studied in three passive treatment systems in western Pennsylvania that differed based on their influent Mn(II) concentrations (20-150 mg/L), system construction ({+-}inoculation with patented Mn(II)-oxidizing bacteria), and bed materials (limestone vs. sandstone). Manganese(II) removal occurred at pH values as low as 5.0 and temperatures as low as 2 C, but was enhanced at circumneutral pH and warmer temperatures. Trace metals such as Zn, Ni and Co were removed effectively, in most cases preferentially, into the MnO{sub x} precipitates. Based on synchrotron radiation X-ray diffraction and Mn K-edge extended X-ray absorption fine structure spectroscopy, the predominant Mn oxides at all sites were poorly crystalline hexagonal birnessite, triclinic birnessite and todorokite. The surface morphology of the MnOx precipitates from all sites was coarse and 'sponge-like' composed of nm-sized lathes and thin sheets. Based on scanning electron microscopy (SEM), MnO{sub x} precipitates were found in close proximity to both prokaryotic and eukaryotic organisms. The greatest removal efficiency of Mn(II) occurred at the one site with a higher pH in the bed and a higher influent total organic C (TOC) concentration (provided by an upstream wetland). Biological oxidation of Mn(II) driven by heterotrophic activity was most likely the predominant Mn removal mechanism in these systems. Influent water chemistry and Mn(II) oxidation kinetics affected the relative distribution of MnOx mineral assemblages in CMD treatment systems.

  6. Spectral masking of goethite in abandoned mine drainage systems: implications for Mars

    USGS Publications Warehouse

    Cull, Selby; Cravotta, Charles A.; Klinges, Julia Grace; Weeks, Chloe

    2014-01-01

    Remote sensing studies of the surface of Mars use visible- to near-infrared (VNIR) spectroscopy to identify hydrated and hydroxylated minerals, which can be used to constrain past environmental conditions on the surface of Mars. However, due to differences in optical properties, some hydrated phases can mask others in VNIR spectra, complicating environmental interpretations. Here, we examine the role of masking in VNIR spectra of natural precipitates of ferrihydrite, schwertmannite, and goethite from abandoned mine drainage (AMD) systems in southeastern Pennsylvania. Mixtures of ferrihydrite, schwertmannite, and goethite were identified in four AMD sites by using X-ray diffractometry (XRD), and their XRD patterns compared to their VNIR spectra. We find that both ferrihydrite and schwertmannite can mask goethite in VNIR spectra of natural AMD precipitates. These findings suggest that care should be taken in interpreting environments on Mars where ferrihydrite, schwertmannite, or goethite are found, as the former two may be masking the latter. Additionally, our findings suggest that outcrops on Mars with both goethite and ferrihydrite/schwertmannite VNIR signatures may have high relative abundances of goethite, or the goethite may exist in a coarsely crystalline phase.

  7. Hydrochemical data for the Truckee River drainage system, California and Nevada

    SciTech Connect

    Benson, L.V.

    1984-01-01

    Surface-water samples were collected from the Truckee River drainage system during 1975, 1976, and 1981. Data resulting from chemical analyses of these samples, as well as certain other previously unpublished data, are tabulated in this report. The report contains the following hydrochemical data: (1) chemical composition of 21 tributaries to Lake Tahoe and the Truckee River upstream from Farad, California (May and October 1971, and June 1972); (2) chemical composition of the Truckee River at Tahoe City (January 1968 to January 1975) and at Farad, California (January 1968 to June 1980), and of the Little Truckee River upstream from Stampede Reservoir, California (January 1968 to April 1980); (3) chemical composition of the Truckee River at 11 sites from Tahoe City, California, to Nixon, Nevada (June 4 and September 3, 1975); (4) historical chemical analyses of water from Pyramid Lake, Nevada (1882 to 1973); (5) chemical composition (November 1975 to December 1976), water temperature (January 1976 to November 1977), and dissolved oxygen (January 1976 to November 1977) at various depths in Pyramid Lake, Nevada; (6) chemical composition of pore fluids from and carbonate mineralogy of sediment greater than 2 micrometers in five cores, Pyramid Lake, Nevada; (7) chemical composition of the Truckee River at Farad, California (January to July 1981); and (8) chemical composition of tufa from the Pyramid Lake basin. 9 references, 3 figures, 14 tables.

  8. Local effects of global climate change on the urban drainage system of Hamburg.

    PubMed

    Krieger, Klaus; Kuchenbecker, Andreas; Hüffmeyer, Nina; Verworn, Hans-Reinhard

    2013-01-01

    The Hamburg Water Group owns and operates a sewer network with a total length of more than 5,700 km. There has been increasing attention paid to the possible impacts of predicted changes in precipitation patterns on the sewer network infrastructure. The primary objective of the work presented in this paper is an estimation of the hydraulic impacts of climate change on the Hamburg drainage system. As a first step, simulated rainfalls based on the regional climate model REMO were compared and validated with long-term precipitation measurements. In the second step, the hydraulic effects on the sewer network of Hamburg have been analyzed based on simulated long-term rainfall series for the period of 2000-2100. Simulation results show a significant increase in combined sewer overflows by 50% as well as an increase in surcharges of storm sewer manholes. However, there is still a substantial amount of uncertainty resulting from model uncertainty and unknown development of future greenhouse gas emissions. So far, there seems to be no sound basis for the implementation of an overall climate factor for sewer dimensioning for the Hamburg region. Nevertheless, possible effects of climate change should be taken into account within the planning process for major sewer extensions or modifications.

  9. Influence of biofilms on heavy metal immobilization in sustainable urban drainage systems (SuDS).

    PubMed

    Feder, Marnie; Phoenix, Vernon; Haig, Sarah; Sloan, William; Dorea, Caetano; Haynes, Heather

    2015-01-01

    This paper physically and numerically models the influence of biofilms on heavy metal removal in a gravel filter. Experimental flow columns were constructed to determine the removal of Cu, Pb and Zn by gabbro and dolomite gravel lithologies with and without natural biofilm from sustainable urban drainage systems (SuDS). Breakthrough experiments showed that, whilst abiotic gravel filters removed up to 51% of metals, those with biofilms enhanced heavy metal removal by up to a further 29%, with Cu removal illustrating the greatest response to biofilm growth. An advection-diffusion equation successfully modelled metal tracer transport within biofilm columns. This model yielded a permanent loss term (k) for metal tracers of between 0.01 and 1.05, correlating well with measured data from breakthrough experiments. Additional 16S rRNA clone library analysis of the biofilm indicated strong sensitivity of bacterial community composition to the lithology of the filter medium, with gabbro filters displaying Proteobacteria dominance (54%) and dolomite columns showing Cyanobacteria dominance (47%).

  10. Accounting for sensor calibration, data validation, measurement and sampling uncertainties in monitoring urban drainage systems.

    PubMed

    Bertrand-Krajewski, J L; Bardin, J P; Mourad, M; Béranger, Y

    2003-01-01

    Assessing the functioning and the performance of urban drainage systems on both rainfall event and yearly time scales is usually based on online measurements of flow rates and on samples of influent effluent for some rainfall events per year. In order to draw pertinent scientific and operational conclusions from the measurement results, it is absolutely necessary to use appropriate methods and techniques in order to i) calibrate sensors and analytical methods, ii) validate raw data, iii) evaluate measurement uncertainties, iv) evaluate the number of rainfall events to sample per year in order to determine performance indicator with a given uncertainty. Based an previous work, the paper gives a synthetic review of required and techniques, and illustrates their application to storage and settling tanks. Experiments show that, controlled and careful experimental conditions, relative uncertainties are about 20% for flow rates in sewer pipes, 6-10% for volumes, 25-35% for TSS concentrations and loads, and 18-276% for TSS removal rates. In order to evaluate the annual pollutant interception efficiency of storage and settling tanks with a given uncertainty, efforts should first be devoted to decrease the sampling uncertainty by increasing the number of sampled events.

  11. An Investigation of Water Level Prediction in Urban Drainage System Using Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Chang, F.; Chiang, Y.; Chiu, Y.; Ho, Y.; Chang, L.; Wang, Y.

    2008-12-01

    The pumping stations are the major hydraulic facilities for the elimination of flood in highly developed cities and therefore play an important role in flood mitigation in metropolitan area. Accurate predictions of inner water level in urban drainage systems are necessary and important for successful operation of pumping stations. In view of the characteristics of artificial neural networks (ANNs), the model was introduced in this study for extracting rainfall-water level patterns from torrential rain events. The Yu-Cheng pumping station, Taipei city, is used as a case study, where historical records which contain information of rainfall amounts and inner water levels are used to train and verify the ANN's performance. First, we directly construct the ANN for multistep ahead water level predictions by using 11 storm events at gauging sites. The optimal structure and parameters are then tested via 3 different events. Second, the storm water management model (SWMM) was utilized for the purpose of generating data at un-gauged sites. Data generated from SWMM were further used to train the ANN. Finally, a comparison of water level prediction between SWMM and ANN are given. Our preliminary results show that the ANN is capable of constructing accurate and reliable water level prediction. The results also exemplify the need for a detailed investigation on SWMM-derived error that could propagate the input error into the ANN models.

  12. Residence times in subsurface hydrological systems, introduction to the Special Issue

    NASA Astrophysics Data System (ADS)

    de Dreuzy, J.-R.; Ginn, T. R.

    2016-12-01

    Interest in the residence time distribution (RTD) as a comprehensive measure of subsurface hydrologic systems is growing. This focus is resulting from recognition that diverse vadose zone, groundwater flows, and transfer between hydrological compartments, are fundamentally related to the system RTD. Furthermore, transport of chemical or biological species and the biogeochemical activities that govern their fate, is principally reflected by the system RTD. Thus the RTD is used in geochemical interpretation of environmental tracers, in direct reactive transport approaches, and ultimately for sustainability and protection assessments in the consideration of transient boundary flows due to climate change or other causes, anthropogenic and/or natural. The RTD has been handled in the past primarily as a byproduct of models. It is now increasingly viewed as an integrative characteristic for which shape-free and generic distributions are developed, that links conceptual hydrology, characterization data, and mathematical models. Intermediary between mechanistic modeling, geochemical data and predictions, the role for residence time distribution is to represent consistently the flow, transport and reactivity processes while reaching the objective of biogeochemical interpretation and sustainability assessment. After some outline of the scientific context, we introduce the contributions of this special issue and conclude with the emerging challenges.

  13. Performance of a vertical subsurface flow (VSF) wetland treatment system using woodchips to treat livestock stormwater.

    PubMed

    Niu, Siping; Guerra, Heidi B; Chen, Yaoping; Park, Kisoo; Kim, Youngchul

    2013-08-01

    This study was conducted to develop a vertical subsurface flow (VSF) wetland remediation system packed with woodchips to control stormwater pollution arising from livestock agriculture. Three lab-scale VSF wetlands were operated with recirculation during the interval (Δ) between storms as 2, 4 and 8 days, respectively. The fed water was 100% recirculated one time per 24 h; the recirculation frequency was 1, 3 and 7 times at Δ of 2, 4 and 8 days, respectively. The constructed wetland systems proved to be effective in reducing total suspended solid (TSS), but also had potential for increasing TSS in the effluent due to the properties of the woodchips. The release of organic matter, especially in the dissolved form, occurred during the initial 60 days. The removal efficiencies of total nitrogen (TN) were 26.2%, 34.1% and 50.0% at Δ of 2, 4 and 8 days, respectively. Nitrification was promoted by the abundant oxygen supplied when the water in wetland was recirculated and fed into the wetland. Denitrification was stable and effective due to the availability of carbon sources. The influent total phosphorus (TP) was reduced from an average of 2.05 mg L(-1) to 1.79 mg L(-1), 1.36 mg L(-1) and 0.86 mg L(-1) at Δ as 2, 4 and 8 days, respectively. The result shows that woodchips can be used as substrate material for VSF wetland treatment systems to control nutrient influx from livestock stormwater.

  14. Comparison of short-term rainfall forecasts for model-based flow prediction in urban drainage systems.

    PubMed

    Thorndahl, Søren; Poulsen, Troels Sander; Bøvith, Thomas; Borup, Morten; Ahm, Malte; Nielsen, Jesper Ellerbæk; Grum, Morten; Rasmussen, Michael R; Gill, Rasphall; Mikkelsen, Peter Steen

    2013-01-01

    Forecast-based flow prediction in drainage systems can be used to implement real-time control of drainage systems. This study compares two different types of rainfall forecast - a radar rainfall extrapolation-based nowcast model and a numerical weather prediction model. The models are applied as input to an urban runoff model predicting the inlet flow to a waste water treatment plant. The modelled flows are auto-calibrated against real-time flow observations in order to certify the best possible forecast. Results show that it is possible to forecast flows with a lead time of 24 h. The best performance of the system is found using the radar nowcast for the short lead times and the weather model for larger lead times.

  15. A Remote Characterization System and a fault-tolerant tracking system for subsurface mapping of buried waste sites

    SciTech Connect

    Sandness, G.A.; Bennett, D.W. ); Martinson, L. ); Bingham, D.N.; Anderson, A.A. )

    1992-08-01

    This paper describes two closely related projects that will provide new technology for characterizing hazardous waste burial sites. The first project, a collaborative effort by five of the national laboratories, involves the development and demonstration of a remotely controlled site characterization system. The Remote Characterization System (RCS) includes a unique low-signature survey vehicle, a base station, radio telemetry data links, satellite-based vehicle tracking, stereo vision, and sensors for noninvasive inspection of the surface and subsurface. The second project, conducted by the Idaho National Engineering Laboratory (INEL), involves the development of a position sensing system that can track a survey vehicle or instrument in the field. This system can coordinate updates at a rate of 200/s with an accuracy better than 0.1% of the distance separating the target and the sensor. It can employ acoustic or electromagnetic signals in a wide range of frequencies and can be operated as a passive or active device.

  16. Influences of specific ions in groundwater on concrete degradation in subsurface engineered barrier system.

    PubMed

    Lin, Wen-Sheng; Liu, Chen-Wuing; Li, Ming-Hsu

    2016-01-01

    Many disposal concepts currently show that concrete is an effective confinement material used in engineered barrier systems (EBS) at a number of low-level radioactive waste (LLW) disposal sites. Cement-based materials have properties for the encapsulation, isolation, or retardation of a variety of hazardous contaminants. The reactive chemical transport model of HYDROGEOCHEM 5.0 was applied to simulate the effect of hydrogeochemical processes on concrete barrier degradation in an EBS which has been proposed to use in the LLW disposal site in Taiwan. The simulated results indicated that the main processes that are responsible for concrete degradation are the species induced from hydrogen ion, sulfate, and chloride. The EBS with the side ditch drainage system effectively discharges the infiltrated water and lowers the solute concentrations that may induce concrete degradation. The redox processes markedly influence the formations of the degradation materials. The reductive environment in the EBS reduces the formation of ettringite in concrete degradation processes. Moreover, the chemical conditions in the concrete barriers maintain an alkaline condition after 300 years in the proposed LLW repository. This study provides a detailed picture of the long-term evolution of the hydrogeochemical environment in the proposed LLW disposal site in Taiwan.

  17. DEVELOPMENT OF A DATA EVALUATION/DECISION SUPPORT SYSTEM FOR REMEDIATION OF SUBSURFACE CONTAMINATION

    EPA Science Inventory

    Subsurface contamination frequently originates from spatially distributed sources of multi-component nonaqueous phase liquids (NAPLs). Such chemicals are typically persistent sources of ground-water contamination that are difficult to characterize. This work addresses the feasi...

  18. A Wide-Band Electromagnetic Impedance Profiling System forNon-Invasive Subsurface Characterization

    SciTech Connect

    Tseng, Hung-Wen; Lee, Ki Ha; Becker, Alex

    2004-12-17

    A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical simulations will be presented to verify this new approach. A set of the impedance difference data acquired at the University of California's Richmond Field Station compares reasonably well with simulation results based on a model obtained with the resistivity method and in situ TDR (time domain reflectometry)measurements.

  19. A preliminary study of a Mars penetrator system for subsurface exobiological exploration

    NASA Technical Reports Server (NTRS)

    Swenson, Byron L.; Mckay, Christopher P.; Carle, Glenn C.

    1987-01-01

    The earth seems to stand alone among the planets of the solar system in that its surface, atmosphere, and hydrosphere provide an environment conducive to the maintenance of life. At one time, Mars was also considered to have the potential to harbor life. However, the absence of detectable organic molecules at the two Viking landing sites and the absence of liquid water anywhere on the surface seems to indicate that life is not present on Mars now. There are, however, many indications that the surface of Mars was less hostile in the distant past and the possibility that life may have existed on primordial Mars or that prebiotic chemistry may have occurred can not be excluded. The search for the organic evidence of this prebiotic or biotic activity will require a subsurface study of possible sediments at several sites. The purpose of this paper is to propose and describe a device termed a penetrator to emplant the required instrumentation beneath the surface (2-4 m) at likely sites to search for the evidence of biogenic organic material. The paper examines, in detail, the rationale for the scientific activity, any issues of technical feasibility, and describes the associated system requirements.

  20. Final Report: A Model Management System for Numerical Simulations of Subsurface Processes

    SciTech Connect

    Zachmann, David

    2013-10-07

    The DOE and several other Federal agencies have committed significant resources to support the development of a large number of mathematical models for studying subsurface science problems such as groundwater flow, fate of contaminants and carbon sequestration, to mention only a few. This project provides new tools to help decision makers and stakeholders in subsurface science related problems to select an appropriate set of simulation models for a given field application.

  1. Multisensor monitoring system for assessment of locust hazard risk in the Lake Balkhash drainage basin.

    PubMed

    Propastin, Pavel

    2012-12-01

    Satellite and ground-based data were combined in a monitoring system to quantify the link between climate conditions and the risk of locust infestations in the southern part of Lake Balkhash's drainage basin in the Republic of Kazakhstan. In this monitoring system, the Normalized Difference Vegetation Index (NDVI), derived from the SPOT-VGT satellite, was used for mapping potential locust habitats and monitoring their area throughout 1998 to 2007. TOPEX/Poseidon and Jason 1 altimeter data were used to track the interannual dynamics of water level in Balkhash Lake. Climate conditions were represented by weather records for air temperature and precipitation during the same period. The classification procedure, based on an analysis of multitemporal dynamics of SPOT-VGT NDVI values observed by individual vegetation classes, generated annual areas of ten land-cover types, which were then categorized as areas with low, medium, and high risk for locust infestation. Statistical analyses showed significant influences of the climatic parameters and the Balkhash Lake hydrological regime on the spatial extend of annual areas of potential locust habitats. The results also indicate that the linkages between locust infestation risk and environmental factors are characterized by time lags. The expansion of locust risk areas are usually preceded by dry, hot years and lower water levels in Balkhash Lake when larger areas of reed grass are free from seasonal flooding. Years with such conditions are favourable for locust outbreaks due to expansion of the habitat areas suitable for locust oviposition and nymphal development. In contrast, years with higher water levels in Balkhash Lake and lower temperature decrease the potential locust habitat area.

  2. Ancient drainage basin of the Tharsis region, Mars: Potential source for outflow channel systems and putative oceans or paleolakes

    USGS Publications Warehouse

    Dohm, J.M.; Ferris, J.C.; Baker, V.R.; Anderson, R.C.; Hare, T.M.; Strom, R.G.; Barlow, N.G.; Tanaka, K.L.; Klemaszewski, J.E.; Scott, D.H.

    2001-01-01

    Paleotopographic reconstructions based on a synthesis of published geologic information and high-resolution topography, including topographic profiles, reveal the potential existence of an enormous drainage basin/aquifer system in the eastern part of the Tharsis region during the Noachian Period. Large topographic highs formed the margin of the gigantic drainage basin. Subsequently, lavas, sediments, and volatiles partly infilled the basin, resulting in an enormous and productive regional aquifer. The stacked sequences of water-bearing strata were then deformed locally and, in places, exposed by magmatic-driven uplifts, tectonic deformation, and erosion. This basin model provides a potential source of water necessary to carve the large outflow channel systems of the Tharsis and surrounding regions and to contribute to the formation of putative northern-plains ocean(s) and/or paleolakes. Copyright 2001 by the American Geophysical Union.

  3. Evolution of closed urinary drainage systems use and associated factors in Spanish hospitals.

    PubMed

    Allepuz-Palau, A; Rosselló-Urgell, J; Vaqué-Rafart, J; Hermosilla-Pérez, E; Arribas-Llorente, J L; Sánchez-Payá, J; Lizán-García, M

    2004-08-01

    Although closed urinary drainage systems (CUDS) reduce the risk of catheter-associated urinary tract infection (CAUTI), open systems are still used in Spain. The object of this work was to describe the progress of CUDS use and factors associated with the drainage system type used in Spanish hospitals. The databases of the EPINE study (Study of Prevalence of Nosocomial Infections in Spain) from 1990 to 2000 were used. The EPINE study includes hospitalized patients of all ages in acute-care Spanish hospitals. Seventy-six thousand, seven hundred and eighty-eight catheterized patients were studied, and the whole database was used for the trend analysis of global hospital-acquired infection (HAI). The patient and the hospital were the two units of observation used in the analysis. Full implementation was defined as 90% CUDS use. A logistic regression model was applied to study factors influencing the use of CUDS and to determine prevalence trend. An odds ratio (OR) >1 indicates an incremental trend. The Pearson correlation coefficient between annual percentage of CUDS use and CAUTI prevalence was calculated. Variables for the year 2000 were compared using the Mann-Whitney U test between hospitals with and without full implementation. The prevalence of urinary catheterized patients in Spain increased from 12.4% in 1990 to 15.2% in 2000 (OR 1.019, 95% CI 1.016-1.021). The proportion of CUDS used increased from 50.6% in 1990 to 70% in 2000 (OR 1.1, 95% CI 1.095-1.104) and correlated with a significant decrease of UTIs (r = 0.65, P = 0.03). In 1990, 28.5% of hospitals had full implementation of CUDS and by 2000 this had risen to 40.3% (OR 1.093, 95% CI 1.06-1.127). Patients in medium (200-500 beds) and large (>500 beds) hospitals, as well as those with three of more diagnoses and two or more intrinsic risk factors had an increased probability of having a CUDS, whereas being hospitalized in areas other than intensive care, being male and less than 65 years old were

  4. Drainage beneath ice sheets: groundwater-channel coupling, and the origin of esker systems from former ice sheets

    NASA Astrophysics Data System (ADS)

    Boulton, G. S.; Hagdorn, M.; Maillot, P. B.; Zatsepin, S.

    2009-04-01

    The nature of the drainage system beneath ice sheets is crucial to their dynamic behaviour but remains problematic. An experimentally based theory of coupling between groundwater and major channel systems is applied to the esker systems in the area occupied the last ice sheet in Europe, which we regard as a fossil imprint of major longitudinal drainage channels. We conclude that the large-scale distribution and spacing of major eskers is consistent with the theory of groundwater control, in which esker spacing is partly controlled by the transmissivity of the bed. It is concluded that esker patterns reflect the large-scale organisation of the subglacial drainage pattern in which channel development is coupled to groundwater flow and to the ice sheet's dynamic regime. The theory is then used to deduce: basal meltwater recharge rates and their spatial variability from esker spacing in an area in which the ice sheet was actively streaming during its final retreat; patterns of palaeo-groundwater flow and head distribution; and the seasonally varying magnitude of discharge from stream tunnels at the retreating ice sheet margin. Major channel/esker systems appear to have been stable at least over several hundred of years during the retreat of the ice sheet, although major dynamic events are demonstrably associated with major shifts in the hydraulic regime. Modelling suggests: that glaciation can stimulate deep groundwater circulation cells that are spatially linked to channel locations, with groundwater flow predominantly transverse to ice flow; that the circulation pattern has the potential to create large-scale anomalies in groundwater chemistry; and that the spacing of channels will change through the glacial cycle, influencing water pressures in stream tunnels, subglacial hydraulic gradients and effective pressure. If the latter is reduced sufficiently, it could trigger enhanced bed deformation, thus coupling drainage to ice sheet movement. It suggests the

  5. Passive treatment of acid mine drainage in systems containing compost and limestone: Laboratory and field results

    SciTech Connect

    Watzlaf, G.R.; Pappas, D.M.

    1996-12-31

    Passive, down-flow systems, consisting of compost and limestone layers, termed successive alkalinity producing systems (SAPS), may be well suited for treatment of mine drainage containing ferric iron and/or aluminum. A column, simulating a SAPS, has been operated in the laboratory for 52 weeks. The 0.16-m diameter column consisted of a 0.30-m thick layer of limestone, a 0.76-m thick layer of spent mushroom compost thick layer of limestone, a 0.76-m thick layer of spent mushroom compost and 0.91 m of free standing water. Actual AMD (pH = 3.02, acidity = 218 mg/L (as CaCO{sub 3}), SO{sub 4} = 600 mg/L, Fe = 16.0 mg/L, Mn = 12.1 mg/L, and Al = 17.1 mg/L) was applied to the column at a rate of 3.8 mL/min. Effluent pH has remained above 6.2 (6.2-7.9) in the column system. A SAPS located in Jefferson County, PA has been monitored for the past 4.5 years. The SAPS has an approximate area of 1000 m{sup 2} and contains a 0.4-m thick layer of limestone, a 0.2-m thick layer of spent mushroom compost, and 1.5 m of free standing water. Mine water (acidity = 335 mg/L (as CaCO{sub 3}), SO{sub 4} = 1270 mg/L, Fe = 246 mg/L, Mn = 38.4 mg/L, and Al = <0.2 mg/L) flowed into the SAPS at a rate of 140 L/min. Water samples from the field and laboratory systems have been collected at strategic locations on a regular basis and analyzed for pH, alkalinity, acidity, Fe{sup 2+}, total Fe, Mn, Al, SO{sub 4}, Ca, Mg, Na, Co, Ni, and Zn. Alkalinity has been generated in both field and laboratory systems by a combination of limestone dissolution and sulfate reduction. The column generated an average of 378 mg/L of alkalinity; 74% due to limestone dissolution and 26% due to bacterial reduction of sulfate. The field SAPS generated an average of 231 mg/L of alkalinity and exhibited seasonal trends.

  6. Impact of Acid Mine Drainage on the hydrogeological system at Sia, Cyprus

    NASA Astrophysics Data System (ADS)

    Ng, Stephen; Malpas, John

    2013-04-01

    Discontinued mining of the volcanogenic massive sulphide ore bodies of Cyprus has left significant environmental concerns including Acid Mine Drainage. Remnant sulphide ore and tailings in waste dumps react with oxygenated rainwater to produce sulphuric acid, a process which is multiplied when metal-loving acidophilic bacteria are present. Given that Cyprus has a Mediterranean climate, characterized by its warm and dry summers and cool and wet winters, the low pH effluent with high levels of trace elements, particularly metals, is leached out of the waste tips particularly during the wet season. The Sia site includes an open mine-pit lake, waste rock and tailings dumps, a river leading to a downstream dam-lake, and a localised groundwater system. The study intends to: identify the point source and nature of contamination; analyze the mechanism and results of local acid generation; and understand how the hydrogeological system responds to seasonal variations. During two sampling campaigns, in the wet and dry seasons of 2011, water samples were collected from the mine pit lake, from upstream of the adjacent river down to the dam catchment, and from various boreholes close to the sulphide mine. The concentration of ions in waters varies between wet and dry seasons but, in both, relative amounts are directly related to pH. In the mine-pit lake, Fe, Mn, Mg, Cu, Pb, Zn, Ni, Co and Cd are found in higher concentrations in the dry season, as a result of substantial evaporation of water. The Sia River runs continuously in the wet season, and waters collected close to the waste tips have pH as low as 2.5 and higher concentrations of Al, Cu, Fe and Zn. Further downstream there is a significant decrease in trace metal contents with a concomitant rise of pH. Al and Fe dominate total cation content when pH is lower than 4. Al is derived from the weathering of clay minerals, especially during the wet season. Fe is derived from the oxidation of pyrite. Once pH's exceed 4, a white

  7. Effect of COD/N ratio on removal performances in two subsurface wastewater infiltration systems.

    PubMed

    Fei Jing Pan Deli Tong Linli Huang Long Yu Yafei Sun Shiyue Qi Yaoyao Huang, Hexin

    2017-01-24

    Dissolved oxygen (DO), removal of COD, TP and nitrogen in subsurface wastewater infiltration systems (SWISs)with/without intermittent aeration under different influent COD/N ratios were investigated. Aerobic conditions were effectively developed in 50 cm depth of the matrix and anoxic or anaerobic conditions were not changed in 80 and 110 cm depth by intermittent aeration, which encouraged nitrification. Increased influent COD/N ratio led to lower COD and nitrogen removal in conventional SWISs. Sufficient carbon source in high COD/N ratio influent promoted denitrification with intermittent aeration. High removal rates of COD (95.68±0.21%), TP (92.02±0.28%), NH4+-N (99.33±0.05%) and TN (89.65±0.6%) were obtained with influent COD/N ratio of 12 in aerated SWISs. Under the COD/N ratio of 12 and 18, intermittent aeration boosted the growth and reproduction of nitrifying bacteria and denitrifying bacteria. Meanwhile, nitrate and nitrite reductase activities with intermittent aeration were higher than that without aeration in 80 and 110 cm depth.

  8. Water use efficiency of different sugarcane genotypes irrigated by a subsurface drip irrigation system

    NASA Astrophysics Data System (ADS)

    Silva, A. L. B. O.; Pires, R. C. M.; Ribeiro, R. V.; Machado, E. C.; Rolim, G. S.; Magalhães Filho, J. R.; Marchiori, P. E. R.

    2012-04-01

    The biofuel production is a growing concern on modern society due to the agricultural sustainability, in which both food and energy supplying should be take into account. The agroclimatic zoning indicates that sugarcane expansion in Brazil can only take place in marginal lands, where water deficit occurs and irrigation is necessary. The aim of this work was to evaluate water consumption and the water use efficiency of two sugarcane genotypes irrigated by a subsurface drip irrigation system. The field experiment was carried out in Campinas SP Brazil, with IACSP95-5000 and SP79-1011 varieties. Those varieties have different canopy characteristics and development, with IACSP95-5000 being more responsive to soil water availability and presenting higher light interception when compared to SP79-1011. Crop evapotranspiration (ETc) was calculated through field water balance from August 2010 to March 2011. Soil water content was evaluated by using a capacitance probe, sampling different depths in soil profile until 1-m. IACSP95-5000 had higher water consumption than SP79-1011. The mean ETc value of IACSP95-5000 was 5.0 mm day-1, whereas SP79-1011 showed 3.7 mm day-1. ETc values were positively correlated to biomass production, with IACSP95-5000 exhibiting higher growth and water use efficiency than SP79-1011.

  9. Depositional systems and Karst geology of the Ellenburger group (lower ordovician), subsurface West Texas

    SciTech Connect

    Kerans, C.

    1990-01-01

    The Ellenburger Group of Texas contains estimated reserves of 1.15 billion barrels of oil and 2.2 billion barrels of oil equivalent. Despite its economic significance, comparatively little is known about the subsurface Ellenburger in West Texas; thus, this book presents a regional model of Ellenburger deposition and diagenesis. Using associations of lithologies and sedimentary structures observed in core, the author identified six depositional systems in the Ellenburger: fan delta-marginal marine, lower tidal flat, high-energy restricted shelf, low-energy restricted shelf, upper tidal flat, and open shallow water shelf. Diagenesis was dominated by three major styles of dolomitization: very fine crystalline dolomite (5-20 {mu}m), in tidal-flat facies; fine to medium crystalline dolomite (20-100 {mu}m), widespread in all facies; and coarse crystalline replacement mosaic dolomite and saddle dolomite cement, which formed in a burial setting after pre-Simpson karst formation and before Pennsylvanian faulting, uplift, and erosion. Other diagenetic events were karst-related dissolution episodes associated with repeated uplift and exposure and subsequent dedolomitization of the Ellenburger platform.

  10. Drainage systems of Lonar Crater, India: Contributions to Lonar Lake hydrology and crater degradation

    NASA Astrophysics Data System (ADS)

    Komatsu, Goro; Senthil Kumar, P.; Goto, Kazuhisa; Sekine, Yasuhito; Giri, Chaitanya; Matsui, Takafumi

    2014-05-01

    Lonar, a 1.8-km-diameter impact crater in India, is a rare example of terrestrial impact craters formed in basaltic bedrock. The estimated age of the crater ranges widely from less than 12 ka to over 600 ka, but the crater preserves a relatively pristine morphology. We conducted a study of various drainage systems of Lonar Crater. The crater floor hosts a shallow 5-m-deep lake, which fluctuates seasonally. Our investigation reveals that the lake level is influenced by surface runoff that is active during the monsoon and groundwater input effective during both the rainy and the dry seasons. The groundwater discharge is observed as springs on the inner rim walls corresponding to weathered vesicular basalt and/or proximal ejecta, which are underlain by thick massive basalt layers. This observation indicates that groundwater movement is lithologically controlled: it passes preferentially through permeable vesicular basalt or proximal ejecta but is hindered in less permeable massive basalt. It is hypothesized that groundwater is also structurally controlled by dipping of basalt layers, interconnectivity of the permeable lithologic units through fractures, and preferential pathways such as fractures within the permeable lithologic units. Investigation on hydrological processes at Lonar Crater and its lake could provide useful insights into purported paleo-crater lakes presumably formed in the basaltic crust of Mars. The Lonar Crater interior shows signs of degradation in the forms of gullies and debris flows, and the Dhar valley incising in the rim leading to form a fan delta. The ejecta surface is characterized by the presence of channels, originating from the rim area and extending radially away from the crater center. The channels probably resulted from surface runoff, and its erosion contributes to the removal of the ejecta. Lonar Crater is a valuable analog site for studying degradation processes with potential application to impact craters occurring on

  11. Decision making for urban drainage systems under uncertainty caused by weather radar rainfall measurement

    NASA Astrophysics Data System (ADS)

    Dai, Qiang; Zhuo, Lu; Han, Dawei

    2015-04-01

    With the rapidly growth of urbanization and population, the decision making for managing urban flood risk has been a significant issue for most large cities in China. A high-quality measurement of rainfall at small temporal but large spatial scales is of great importance to urban flood risk management. Weather radar rainfall, with its advantage of short-term predictability and high spatial and temporal resolutions, has been widely applied in the urban drainage system modeling. It is recognized that weather radar is subjected to many uncertainties and many studies have been carried out to quantify these uncertainties in order to improve the quality of the rainfall and the corresponding outlet flow. However, considering the final action in urban flood risk management is the decision making such as flood warning and whether to build or how to operate a hydraulics structure, some uncertainties of weather radar may have little or significant influence to the final results. For this reason, in this study, we aim to investigate which characteristics of the radar rainfall are the significant ones for decision making in urban flood risk management. A radar probabilistic quantitative rainfall estimated scheme is integrated with an urban flood model (Storm Water Management Model, SWMM) to make a decision on whether to warn or not according to the decision criterions. A number of scenarios with different storm types, synoptic regime and spatial and temporal correlation are designed to analyze the relationship between these affected factors and the final decision. Based on this, parameterized radar probabilistic rainfall estimation model is established which reflects the most important elements in the decision making for urban flood risk management.

  12. Improved regional groundwater flow modeling using drainage features: a case study of the central northern karst aquifer system of Puerto Rico (USA)

    NASA Astrophysics Data System (ADS)

    Ghasemizadeh, Reza; Yu, Xue; Butscher, Christoph; Padilla, Ingrid Y.; Alshawabkeh, Akram

    2016-09-01

    In northern Puerto Rico (USA), subsurface conduit networks with unknown characteristics, and surface features such as springs, rivers, lagoons and wetlands, drain the coastal karst aquifers. In this study, drain lines connecting sinkholes and springs are used to improve the developed regional model by simulating the drainage effects of conduit networks. Implemented in an equivalent porous media (EPM) approach, the model with drains is able to roughly reproduce the spring discharge hydrographs in response to rainfall. Hydraulic conductivities are found to be scale dependent and significantly increase with higher test radius, indicating scale dependency of the EPM approach. Similar to other karst regions in the world, hydraulic gradients are steeper where the transmissivity is lower approaching the coastline. This study enhances current understanding of the complex flow patterns in karst aquifers and suggests that using a drainage feature improves modeling results where available data on conduit characteristics are minimal.

  13. VALUING ACID MINE DRAINAGE REMEDIATION IN WEST VIRGINIA: A HEDONIC MODELING APPROACH INCORPORATING GEOGRAPHIC INFORMATION SYSTEMS

    EPA Science Inventory

    States with active and abandoned mines face large private and public costs to remediate damage to streams and rivers from acid mine drainage (AMD). Appalachian states have an especially large number of contaminated streams and rivers, and the USGS places AMD as the primary source...

  14. Investigation of denitrifying microbe communities within an agricultural drainage system fitted with low-grade weirs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enhancing wetland characteristics in agricultural drainage ditches with the use of low-grade weirs, has been identified as a potential best management practice (BMP) to mitigate nutrient runoff from agriculture landscapes. This study examined microbe community abundance and diversity involved in den...

  15. Process-Based Characterizations of Subsurface Fluid Pressures for a Devil's Slide-like System

    NASA Astrophysics Data System (ADS)

    Thomas, M.; Loague, K.

    2014-12-01

    Coastal margins commonly host slope stability hazards that are influenced by hydrologic, geologic, and / or anthropogenic perturbations. A firm foundation for rigorously understanding the component contributions and process-based linkages among hydrologic and geomorphic response is comprehensive physics-based simulation. This study is motivated by the hydrologically-driven, creeping and episodic deep-seated bedrock slides that intersect a former section of the Pacific Coast Highway in the active landslide zone at Devil's Slide near Pacifica, California. For this study, deterministic-conceptual hydrogeologic simulation was employed to estimate fluid pressures for saturated three-dimensional (3D) subsurface systems. One-dimensional (1D) vertical, transient, variably-saturated simulations were conducted to establish the position of the water table (i.e., the upper boundary condition) for the 3D steady-state saturated problems which encode the geologic information for heterogeneous and anisotropic systems. The concept-development effort undertaken here demonstrates that, for a Devil's Slide-like system: (i) specific climatic conditions facilitate variable lag times associated with water-table dynamics, (ii) recharge is the most sensitive parameter to establish risk-averse estimates of fluid pressure, (iii) nuances in the 3D flow field related to fault zone characteristics markedly influence fluid pressures, and (iv) it is unlikely that seasonal fluctuations in the regional water table account for severe failure modes. The simulated fluid pressures encourage new interdisciplinary data discovery to investigate the spatial and temporal persistence of perched water in the study area. To capture event-driven failures for the Devil's Slide site, future efforts should develop characterizations of the unsaturated near surface with a rigor similar to the treatment of the saturated zone demonstrated by this study.

  16. Use of natural and applied tracers to guide targeted remediation efforts in an acid mine drainage system, Colorado Rockies, USA

    USGS Publications Warehouse

    Cowie, Rory; Williams, Mark W.; Wireman, Mike; Runkel, Robert L.

    2014-01-01

    Stream water quality in areas of the western United States continues to be degraded by acid mine drainage (AMD), a legacy of hard-rock mining. The Rico-Argentine Mine in southwestern Colorado consists of complex multiple-level mine workings connected to a drainage tunnel discharging AMD to passive treatment ponds that discharge to the Dolores River. The mine workings are excavated into the hillslope on either side of a tributary stream with workings passing directly under the stream channel. There is a need to define hydrologic connections between surface water, groundwater, and mine workings to understand the source of both water and contaminants in the drainage tunnel discharge. Source identification will allow targeted remediation strategies to be developed. To identify hydrologic connections we employed a combination of natural and applied tracers including isotopes, ionic tracers, and fluorescent dyes. Stable water isotopes (δ18O/δD) show a well-mixed hydrological system, while tritium levels in mine waters indicate a fast flow-through system with mean residence times of years not decades or longer. Addition of multiple independent tracers indicated that water is traveling through mine workings with minimal obstructions. The results from a simultaneous salt and dye tracer application demonstrated that both tracer types can be successfully used in acidic mine water conditions.

  17. Combination of Successive Alkalinity Producing System (SAPS) and Aeration for Passive Treatment of Highly Acidic Mine Drainage

    NASA Astrophysics Data System (ADS)

    Oh, C.; Ji, S.

    2015-12-01

    Passive treatment system has been widely used for remediation of mine drainage since its advantage of low installation and maintenance cost. The system, however, has also a disadvantage in assuring remediation and management efficiency if the drainage is highly acidic mine drainage. To remediate acid mine drainage (AMD) especially showing high acidity, passive treatment system which consists of successive alkalinity producing system (SAPS) and subsequent aeration pond was proposed and its mechanisms and efficiency was evaluated in this research. Target AMD was obtained from Waryong coal mine and showed typical characteristics of AMD having high metal concentration and low pH (acidity > 300 mg/L as CaCO3). Four experimental cases were conducted; untreated, treated with SAPS, treated with aeration, treated with SAPS and aeration to compare role and mechanism of each unit. Between organic matter and limestone layer which constitute SAPS, the former eliminated most of Fe(III) and Al in the AMD so that the latter was kept from being clogged by precipitates. Net acidity of the AMD rapidly decreased by supplement of alkalinity at the limestone layer. A primary function of SAPS, producing alkalinity constantly without clogging, was attained due to addition a portion of limestone particle into the organic matter layer. The discharge from SAPS had low ORP and DO values because of an anaerobic environment formed at the organic matter layer although its alkalinity was increased. This water quality was unfavorable for Fe(II) to be oxidized. Installation of aeration pond after SAPS, therefore, could be effective way of enhancing oxidation rate of Fe(II). Among the experimental cases, the combination of SAPS and aeration pond was only able to remediate the AMD. This concluded that to remediate highly acidic mine drainage with passive treatment system, three critical conditions were required; pre-precipitation of Fe(III) and Al at organic matter layer in SAPS, constant alkalinity

  18. Drainage systems associated with mid-ocean channels and submarine Yazoos: Alternative to submarine fan depositional systems

    SciTech Connect

    Hesse, R. )

    1989-12-01

    Submarine drainage systems associated with mid-ocean channels and Yazoo River-type tributaries in small ocean basins represent a contrast to deep-sea fan depositional systems. Deep-sea fans are diverging sediment-dispersal systems of distributary fan valleys. Deep-sea channel-submarine-yazoo systems, on the other hand, form centripetally converging patterns of tributaries and yazoo-type satellite channels that join a major basin-draining (mid-ocean) channel. The facies model for such systems is characterized by randomly stacked fining-upward, gravelly, and sandy channel-fill and submarine point-bar sequences of the main channel encased in fine-grained overbank deposits. Second-order channels contain sandy proximal overbank deposits, whereas the levees of the main channel are predominantly composed of silt and clay. Second-order channels may be braided and may broaden into braid plains. Morphology and surficial sediment distribution have been studied within the Northwest Atlantic Mid-Ocean Channel of the Labrador Sea and its associated levees and yazoo-type (and other) tributaries.

  19. Implementation of a multi-modal mobile sensor system for surface and subsurface assessment of roadways

    NASA Astrophysics Data System (ADS)

    Wang, Ming; Birken, Ralf; Shahini Shamsabadi, Salar

    2015-03-01

    There are more than 4 million miles of roads and 600,000 bridges in the United States alone. On-going investments are required to maintain the physical and operational quality of these assets to ensure public's safety and prosperity of the economy. Planning efficient maintenance and repair (M&R) operations must be armed with a meticulous pavement inspection method that is non-disruptive, is affordable and requires minimum manual effort. The Versatile Onboard Traffic Embedded Roaming Sensors (VOTERS) project developed a technology able to cost- effectively monitor the condition of roadway systems to plan for the right repairs, in the right place, at the right time. VOTERS technology consists of an affordable, lightweight package of multi-modal sensor systems including acoustic, optical, electromagnetic, and GPS sensors. Vehicles outfitted with this technology would be capable of collecting information on a variety of pavement-related characteristics at both surface and subsurface levels as they are driven. By correlating the sensors' outputs with the positioning data collected in tight time synchronization, a GIS-based control center attaches a spatial component to all the sensors' measurements and delivers multiple ratings of the pavement every meter. These spatially indexed ratings are then leveraged by VOTERS decision making modules to plan the optimum M&R operations and predict the future budget needs. In 2014, VOTERS inspection results were validated by comparing them to the outputs of recent professionally done condition surveys of a local engineering firm for 300 miles of Massachusetts roads. Success of the VOTERS project portrays rapid, intelligent, and comprehensive evaluation of tomorrow's transportation infrastructure to increase public's safety, vitalize the economy, and deter catastrophic failures.

  20. The role of the lymphatic system in drainage of cerebrospinal fluid and aqueous humour.

    PubMed

    Bradbury, M W; Cole, D F

    1980-02-01

    1. The jugular lymphatic trunks were cannulated in anaesthetized rabbits and cats. Over 6-8 hr, the mean lymph flow was 2.3 microliters min-1 in the rabbit (one side only) and 5.0 microliters min-1 in the cat (sum of both sides). 2. After a single injection of radio-iodinated albumin into a lateral cerebral ventricle without significant rise in pressure, a mean of 14.4% of the radioactivity was recovered in deep cervical lymph of one side in the rabbit and of 12.9% in that of both sides in the cat. 3. During slow infusion of [125I]albumin and fluorescent dextran of 150,000 mol. wt. into a lateral ventricle of the cat at 20 microliters min-1, radioactivity and fluorescence reached plateaus in deep cervical lymph at 47.4 and 50.0% of their concentrations in cisternal c.s.f. respectively. 4. No significant radioactivity, other than from blood, was detected in superficial cervical lymph after intraventricular injection of radio-iodinated albumin in the cat. 5. No significant radioactivity, other than from blood, was detected in deep cervical lymph of the rabbit or in deep and superficial cervical lymph of the cat within 6 hr after injection of radio-iodinated albumin into the aqueous humour or orbital fat. 6. Gradients of radioactivity in tissues within the orbit suggested that there is a small flow of c.s.f., 0.05-0.15 microliters min-1 in the rabbit, passing centrifugally along the subarachnoid space of the optic nerve, through the posterior part of the globe and into the orbital tissue. Also a small proportion of aqueous humour, 1-2% or more, drains through the anterior sclera into the surrounding tissue. 7. A substantial quantity of cerebrospinal fluid drains into the deep cervical lymphatic system of the rabbit, 30% or more, and of the cat, 10-15% or more. The small component of aqueous humour drainage passing through the wall of the glove does not enter cervical lymph within 6 hr, if at all.

  1. Hydrogeology, ground-water movement, and subsurface storage in the Floridan aquifer system in southern Florida

    USGS Publications Warehouse

    Meyer, Frederick W.

    1989-01-01

    saltwater in the Floridan aquifer system probably is connate or unflushed seawater from high stands of sea level. The principal use of the Floridan aquifer system in southern Florida is for subsurface storage of liquid waste. The Boulder Zone of the Lower Floridan aquifer is extensively used as a receptacle for injected treated municipal wastewater, oil field brine, and, to a lesser extent, industrial wastewater. Pilot studies indicate a potential for cyclic storage of freshwater in the Upper Floridan aquifer in southern Florida.

  2. Insights into the ancient Mississippi drainage system from detrital zircons analyses of the modern Mississippi deep-sea fan

    NASA Astrophysics Data System (ADS)

    Fildani, A.; McKay, M. P.; Stockli, D. F.; Clark, J. D.; Weislogel, A. L.; Dykstra, M.; Hessler, A. M.

    2014-12-01

    The modern Mississippi deep-sea fan is a large-scale accumulation of Quaternary sediment deposited in the Gulf of Mexico by the modern Mississippi River via the Mississippi delta. The Mississippi River has a well-characterized drainage system extending across North America from the western Rocky Mountains to the Appalachians in the east. Deep-water sand samples of buried channel-fill and lobe deposits of the Mississippi fan from selected Sites of Leg 96 of the Deep Sea Drilling Project (DSDP) and were integrated with USGS piston core samples from the most recent lobe for detrital zircon U-Pb isotopic analysis. Since the modern Mississippi River has a well-known catchment, the detrital zircon age 'signal' observed in the deep-water sediments can therefore be used as an actualistic study of the detrital zircon provenance signatures resulting from modern drainage patterns. Based on this approach, we compare this dataset with published data and observe minor variability in the detrital zircon signature through time. Populations sourced from the Western North American Cordillera are consistent through time in terms of ages, however Paleocene sediments are slightly enriched in Yavapai-Mazatzal zircons sourced from southwestern continental U.S.. Grenville- and Appalachian-derived zircons reflect minor variation in sediment input from the Appalachian Mountains and related deposits in the eastern Mississippi River catchment. When compared to published Upper Jurassic Norphlet formation detrital zircon data, the Paleocene published dataset and the newly acquired modern sands are partly depleted of Appalachian-derived zircons. This paucity in Appalachian age zircon in Paleocene-to-modern sediments suggests a reconfiguration of the Mississippi River drainage prior to Tertiary time. Since this realignment, the Mississippi River drainage has remained relatively unchanged. Piston core samples from the most recent lobe yielded zircons indicating a recent influx of Appalachian

  3. Drainage basins and channel incision on Mars.

    PubMed

    Aharonson, Oded; Zuber, Maria T; Rothman, Daniel H; Schorghofer, Norbert; Whipple, Kelin X

    2002-02-19

    Measurements acquired by the Mars Orbiter Laser Altimeter on board the Mars Global Surveyor indicate that large drainage systems on Mars have geomorphic characteristics inconsistent with prolonged erosion by surface runoff. We find the topography has not evolved to an expected equilibrium terrain form, even in areas where runoff incision has been previously interpreted. By analogy with terrestrial examples, groundwater sapping may have played an important role in the incision. Longitudinally flat floor segments may provide a direct indication of lithologic layers in the bedrock, altering subsurface hydrology. However, it is unlikely that floor levels are entirely due to inherited structures due to their planar cross-cutting relations. These conclusions are based on previously unavailable observations, including extensive piece-wise linear longitudinal profiles, frequent knickpoints, hanging valleys, and small basin concavity exponents.

  4. Drainage discharge impacts on hydrology and water quality of receiving streams in the wheatbelt of Western Australia.

    PubMed

    Ali, Riasat; Silberstein, Richard; Byrne, John; Hodgson, Geoff

    2013-11-01

    The use of surface and subsurface drainage to manage waterlogging and salinity in dryland (rainfed) and irrigated agricultural systems is common throughout the world. The drainage systems often discharge into natural streams. The same is true for the wheatbelt drainage systems in south-western Australia, where 11,000 km (ABS 2003) of artificial drains have been constructed within the last two decades. Prior to this study, the likely impacts of this discharge on the streambed chemistry and water quality of receiving streams were largely unknown. The study evaluated these impacts in creeks receiving the drainage discharge from engineering options in four river systems in south-western Australia. This study clearly showed elevated levels of metals ions, EC and pH in the stream water at treated sites relative to their levels at untreated sites. At most sites, impacts of drainage discharge were observed on the streambed electrical conductivity (EC) and pH (both in 1:5 extract) in the receiving streams; however, there was little evidence of impact on metal ion content in the streambed soil. The study found no clear differences in the dynamics of the watertable adjacent to streams whether they received drainage discharge or not, irrespective of the size of the artificial drainage systems.

  5. Effect of surface inlet type on suspended sediment transported through a subsurface drain tile system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Throughout the Prairie Pothole Region, subsurface tile and surface inlets are used to remove water from low-lying or poorly-drained soils. Open inlets are being increasingly converted to buried inlets in which perforated tile is placed in a trench of rock (i.e., a French drain) and buried below a la...

  6. Surface and subsurface inspection of food safety and quality using a line-scan Raman system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper presents a line-scan Raman platform for food safety and quality research, which can be configured for Raman chemical imaging (RCI) mode for surface inspection and spatially offset Raman spectroscopy (SORS) mode for subsurface inspection. In the RCI mode, macro-scale imaging was achieved u...

  7. Reconnecting tile drainage to riparian buffer hydrology for enhanced nitrate removal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian buffers are a proven practice for removing NO3 from both overland flow and shallow groundwater. However, in landscapes with artificial subsurface (tile) drainage most of the subsurface flow leaving fields is passed through the buffers in drainage pipes leaving little opportunity for NO3 rem...

  8. Numerical modelling on fate and transport of petroleum hydrocarbons in an unsaturated subsurface system for varying source scenario

    NASA Astrophysics Data System (ADS)

    Berlin, M.; Vasudevan, M.; Kumar, G. Suresh; Nambi, Indumathi M.

    2015-04-01

    The vertical transport of petroleum hydrocarbons from a surface spill through an unsaturated subsurface system is of major concern in assessing the vulnerability of groundwater contamination. A realistic representation on fate and transport of volatile organic compounds at different periods after spill is quite challenging due to the variation in the source behaviour at the surface of spill as well as the variation in the hydrodynamic parameters and the associated inter-phase partitioning coefficients within the subsurface. In the present study, a one dimensional numerical model is developed to simulate the transport of benzene in an unsaturated subsurface system considering the effect of volatilization, dissolution, adsorption and microbial degradation of benzene for (i) constant continuous source, (ii) continuous decaying source, and (iii) residual source. The numerical results suggest that volatilization is the important sink for contaminant removal considering the soil air migration within the unsaturated zone. It is also observed that the coupled effect of dissolution and volatilization is important for the decaying source at the surface immediately after the spill, whereas rate-limited dissolution from residually entrapped source is responsible for the extended contamination towards later period.

  9. Metabolic Strategies in Energy-Limited Microbial Communities in the Anoxic Subsurface (Frasassi Cave System, Italy)

    NASA Astrophysics Data System (ADS)

    McCauley, R. L.; Jones, D. S.; Schaperdoth, I.; Steinberg, L.; Macalady, J. L.

    2010-12-01

    Two major sources of energy, light and chemical potential, are available to microorganisms. However, energy is not always abundant and is often a limiting factor in microbial survival and replication. The anoxic, terrestrial subsurface offers a unique opportunity to study microorganisms and their potentially novel metabolic strategies that are relevant for understanding biogeochemistry and biosignatures as related to the non-photosynthetic, energy-limited environments on the modern and ancient Earth and elsewhere in the solar system. Geochemical data collected in a remote stratified lake 600 m below ground surface in the sulfidic Frasassi cave system (Italy) suggest that little redox energy is available for life, consistent with low signal from domain-specific FISH probes. The carbon isotope signatures of biofilms (-33‰) and DIC (-9‰) in the anoxic water suggest in situ production by lithoautotrophs using RuBisCO. 16S rDNA libraries constructed from the biofilm are dominated by diverse sulfate reducing bacteria. The remaining bacterial and archaeal clones affiliate with more than 11 major uncultivated or novel prokaryotic lineages. Diverse dsrAB gene sequences are consistent with high sulfate concentrations and undetectable or extremely low oxygen, nitrate, and iron concentrations. However, the electron donor for sulfate reduction is unclear. Methane is detectable in the anoxic water although no 16S rDNA sequences associated with known methanogens or anaerobic methane oxidizers were retrieved. mcrA gene sequences retrieved from the biofilm by cloning are not related to cultivated methanogens or to known anaerobic methane oxidizers. Non-purgable organic carbon (NPOC) is below detection limits (i.e. <42 μM acetate) suggesting that alternative electron donors or novel metabolisms may be important. A sample collected by cave divers in October 2009 was pyrosequenced at the Pennsylvania State University Genomics Core Facility using Titanium chemistry (454 Life

  10. Agricultural drainage water management: Potential impact and implementation strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin (and the Lake Erie Basin) area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Dra...

  11. A geographic information system screening tool to tackle diffuse pollution through the use of sustainable drainage systems.

    PubMed

    Todorovic, Zorica; Breton, Neil P

    2014-01-01

    Sustainable drainage systems (SUDS) offer many benefits that traditional solutions do not. Traditional approaches are unable to offer a solution to problems of flood management and water quality. Holistic consideration of the wide range of benefits from SUDS can result in advantages such as improved flood resilience and water quality enhancement through consideration of diffuse pollution sources. Using a geographical information system (GIS) approach, diffuse pollutant sources and opportunities for SUDS are easily identified. Consideration of potential SUDS locations results in source, site and regional controls, leading to improved water quality (to meet Water Framework Directive targets). The paper will discuss two different applications of the tool, the first of which is where the pollutant of interest is known. In this case the outputs of the tool highlight and isolate the areas contributing the pollutants and suggest the adequate SUDS measures to meet the required criteria. The second application is where the tool identifies likely pollutants at a receiving location, and SUDS measures are proposed to reduce pollution with assessed efficiencies.

  12. Morphotectonic evolution of the Alhama de Murcia strike-slip fault overprinting drainage systems inherited from Late Miocene extension (Western Mediterranean-Eastern Betics)

    NASA Astrophysics Data System (ADS)

    Ferrater Gómez, Marta; Booth Rea, Guillermo; Azañón, José Miguel; Pérez Peña, José Vicente; Masana, Eulàlia

    2013-04-01

    The adaptation of drainage systems to the evolution of tectonic structures offers important clues to the tectonic regime present in an area and to the tectonic changes that have occurred. The development of new mountain fronts can produce the abandonment of earlier drainage networks by way of fluvial captures. He we analyse the response of a drainage network inherited from late Miocene extension to tectonic forcing associated to the growth and activity of the Alhama de Murcia sinistral strike-slip in a new transpressive tectonic setting. Rock uplift related to the Alhama de Murcia strike-slip fault and associated structures are conditioning the recent drainage network; overprinting the previous extensional related drainage. We carried out a structural and a qualitative and quantitative relief analysis to understand how the relief has evolved and which are the main active structures that currently control the drainage configuration. We identify river capture sites and we present a geomorphic index analysis using SLk anomalies, hypsometric curves, mountain front sinuosity, the comparison between longitudinal and projected river profiles with the SLk values and the position of active faults and folds, and a slope analysis of the area. The results show: 1) the reactivation of the ending part of the main basins by the current uplift of the Sierra de la Tercia, 2) progressive capture processes related to the growth of the Rambla de Lebor and Totana transverse drainages upon the previous drainage, evidenced by the presence of wind gaps, abrupt changes in flow direction, oblique relationship between current river direction and paleosurfaces maximum slope direction and changes in the lithologic composition of terraces, and 3) basin shapes controlled by the interference between an old NE-SW-directed drainage network controlled by extensional structures and another NW-SE one controlled by the sinistral Alhama de Murcia Fault.

  13. Selenium stable isotope ratios in California agricultural drainage water management systems

    USGS Publications Warehouse

    Herbel, M.J.; Johnson, T.M.; Tanji, K.K.; Gao, S.; Bullen, T.D.

    2002-01-01

    Selenium stable isotope ratios are known to shift in predictable ways during various microbial, chemical, and biological processes, and can be used to better understand Se cycling in contaminated environments. In this study we used Se stable isotopes to discern the mechanisms controlling the transformation of oxidized, aqueous forms of Se to reduced, insoluble forms in sediments of Se-affected environments. We measured 80Se/76Se in surface waters, shallow ground waters, evaporites, digested plants and sediments, and sequential extracts from several sites where agricultural drainage water is processed in the San Joaquin Valley of California. Selenium isotope analyses of samples obtained from the Tulare Lake Drainage District flow-through wetland reveal small isotopic contrasts (mean difference 0.7%o) between surface water and reduced Se species in the underlying sediments. Selenium in aquatic macrophytes was very similar isotopically to the NaOH and Na2SO3 sediment extracts designed to recover soluble organic Se and Se(O), respectively. For the integrated on-farm drainage management sites, evaporite salts were slightly (approximately 0.6%o) enriched in the heavier isotope relative to the inferred parent waters, whereas surface soils were slightly (approximately 1.4%o) depleted. Bacterial or chemical reduction of Se(VI) or Se(IV) may be occurring at these sites, but the small isotopic contrasts suggest that other, less isotopically fractionating mechanisms are responsible for accumulation of reduced forms in the sediments. These findings provide evidence that Se assimilation by plants and algae followed by deposition and mineralization is the dominant transformation pathway responsible for accumulation of reduced forms of Se in the wetland sediments.

  14. Selenium stable isotope ratios in California agricultural drainage water management systems.

    PubMed

    Herbel, Mitchell J; Johnson, Thomas M; Tanji, Kenneth K; Gao, Suduan; Bullen, Thomas D

    2002-01-01

    Selenium stable isotope ratios are known to shift in predictable ways during various microbial, chemical, and biological processes, and can be used to better understand Se cycling in contaminated environments. In this study we used Se stable isotopes to discern the mechanisms controlling the transformation of oxidized, aqueous forms of Se to reduced, insoluble forms in sediments of Se-affected environments. We measured 80Se/76Se in surface waters, shallow ground waters, evaporites, digested plants and sediments, and sequential extracts from several sites where agricultural drainage water is processed in the San Joaquin Valley of California. Selenium isotope analyses of samples obtained from the Tulare Lake Drainage District flow-through wetland reveal small isotopic contrasts (mean difference 0.7%) between surface water and reduced Se species in the underlying sediments. Selenium in aquatic macrophytes was very similar isotopically to the NaOH and Na2SO3 sediment extracts designed to recover soluble organic Se and Se(0), respectively. For the integrated on-farm drainage management sites, evaporite salts were slightly (approximately 0.6%) enriched in the heavier isotope relative to the inferred parent waters, whereas surface soils were slightly (approximately 1.4%) depleted. Bacterial or chemical reduction of Se(VI) or Se(IV) may be occurring at these sites, but the small isotopic contrasts suggest that other, less isotopically fractionating mechanisms are responsible for accumulation of reduced forms in the sediments. These findings provide evidence that Se assimilation by plants and algae followed by deposition and mineralization is the dominant transformation pathway responsible for accumulation of reduced forms of Se in the wetland sediments.

  15. Subsurface Contamination Control

    SciTech Connect

    Y. Yuan

    2001-12-12

    table of derived LRCL for nuclides of radiological importance; (3) Provides an as low as is reasonably achievable (ALARA) evaluation of the derived LRCL by comparing potential onsite and offsite doses to documented ALARA requirements; (4) Provides a method for estimating potential releases from a defective WP; (5) Provides an evaluation of potential radioactive releases from a defective WP that may become airborne and result in contamination of the subsurface facility; and (6) Provides a preliminary analysis of the detectability of a potential WP leak to support the design of an airborne release monitoring system.

  16. Subsurface Contamination Control

    SciTech Connect

    Y. Yuan

    2001-11-16

    table of derived LRCL for nuclides of radiological importance; (3) Provides an as low as is reasonably achievable (ALARA) evaluation of the derived LRCL by comparing potential onsite and offsite doses to documented ALARA requirements; (4) Provides a method for estimating potential releases from a defective WP; (5) Provides an evaluation of potential radioactive releases from a defective WP that may become airborne and result in contamination of the subsurface facility; and (6) Provides a preliminary analysis of the detectability of a potential WP leak to support the design of an airborne release monitoring system.

  17. Genomic comparisons of a bacterial lineage that inhabits both marine and terrestrial deep subsurface systems

    PubMed Central

    Glavina del Rio, Tijana; Tringe, Susannah G.; Stepanauskas, Ramunas

    2017-01-01

    It is generally accepted that diverse, poorly characterized microorganisms reside deep within Earth’s crust. One such lineage of deep subsurface-dwelling bacteria is an uncultivated member of the Firmicutes phylum that can dominate molecular surveys from both marine and continental rock fracture fluids, sometimes forming the sole member of a single-species microbiome. Here, we reconstructed a genome from basalt-hosted fluids of the deep subseafloor along the eastern Juan de Fuca Ridge flank and used a phylogenomic analysis to show that, despite vast differences in geographic origin and habitat, it forms a monophyletic clade with the terrestrial deep subsurface genome of “Candidatus Desulforudis audaxviator” MP104C. While a limited number of differences were observed between the marine genome of “Candidatus Desulfopertinax cowenii” modA32 and its terrestrial relative that may be of potential adaptive importance, here it is revealed that the two are remarkably similar thermophiles possessing the genetic capacity for motility, sporulation, hydrogenotrophy, chemoorganotrophy, dissimilatory sulfate reduction, and the ability to fix inorganic carbon via the Wood-Ljungdahl pathway for chemoautotrophic growth. Our results provide insights into the genetic repertoire within marine and terrestrial members of a bacterial lineage that is widespread in the global deep subsurface biosphere, and provides a natural means to investigate adaptations specific to these two environments.

  18. Phosphorus fate, management, and modeling in artificially drained systems.

    PubMed

    Kleinman, Peter J A; Smith, Douglas R; Bolster, Carl H; Easton, Zachary M

    2015-03-01

    Phosphorus (P) losses in agricultural drainage waters, both surface and subsurface, are among the most difficult form of nonpoint source pollution to mitigate. This special collection of papers on P in drainage waters documents the range of field conditions leading to P loss in drainage water, the potential for drainage and nutrient management practices to control drainage losses of P, and the ability of models to represent P loss to drainage systems. A review of P in tile drainage and case studies from North America, Europe, and New Zealand highlight the potential for artificial drainage to exacerbate watershed loads of dissolved and particulate P via rapid, bypass flow and shorter flow path distances. Trade-offs are identified in association with drainage intensification, tillage, cover crops, and manure management. While P in drainage waters tends to be tied to surface sources of P (soil, amendments or vegetation) that are in highest concentration, legacy sources of P may occur at deeper depths or other points along drainage flow paths. Most startling, none of the major fate-and-transport models used to predict management impacts on watershed P losses simulate the dominant processes of P loss to drainage waters. Because P losses to drainage waters can be so difficult to manage and to model, major investment are needed (i) in systems that can provide necessary drainage for agronomic production while detaining peak flows and promoting P retention and (ii) in models that can adequately describe P loss to drainage waters.

  19. [Treatment of marine-aquaculture effluent by the multi-soil-layer (MSL) system and subsurface flow constructed wetland].

    PubMed

    Song, Ying; Huang, Yu-ting; Ge, Chuan; Zhang, Hao; Chen, Xin; Zhang, Zhi-jianz; Luo, An-cheng

    2014-09-01

    To evaluate the feasibility of using multi-soil-layer (MSL) system and subsurface flow constructed wetland to treat the wastewater of marine cultured Penaeus vannamei and to determine the suitable process for the local aquaculture wastewater pollution characteristics. In this study, MSL system and four constructed wetland systems with Spartina anglica, Phragmites australis, Typha latifolia and unplanted system were evaluated for their potentials of pollutants removal capacity. The results showed the average removal rates of chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), ammonia nitrogen (NH(4)+ -N) and nitrate (NO-(3) -N) by MSL system were 80. 38% ± 2. 14% , 68. 14% ± 3.51% , 40.79% ± 3. 10% , 42. 68% ± 2.90% and 54. 19% ± 5. 15% , respectively. Additionally, the ability of pollutants removal of other four wetland systems decreased in the order: Spartina anglica, Phragmites australis, Typha latifolia and unplanted system.

  20. Study on nitrogen removal enhanced by shunt distributing wastewater in a constructed subsurface infiltration system under intermittent operation mode.

    PubMed

    Li, Yinghua; Li, Haibo; Sun, Tieheng; Wang, Xin

    2011-05-15

    Subsurface wastewater infiltration system is an efficient and economic technology in treating small scattered sewage. The removal rates are generally satisfactory in terms of COD, BOD(5), TP and SS removal; while nitrogen removal is deficient in most of the present operating SWIS due to the different requirements for the presence of oxygen for nitrification and denitrification processes. To study the enhanced nitrogen removal technologies, two pilot subsurface wastewater infiltration systems were constructed in a village in Shenyang, China. The filled matrix was a mixture of 5% activated sludge, 65% brown soil and 30% coal slag in volume ratio for both systems. Intermittent operation mode was applied in to supply sufficient oxygen to accomplish the nitrification; meanwhile sewage was supplemented as the carbon source to the lower part in to denitrify. The constructed subsurface wastewater infiltration systems worked successfully under wetting-drying ratio of 1:1 with hydraulic loading of 0.081 m(3)/(m(2)d) for over 4 months. Carbon source was supplemented with shunt ratio of 1:1 and shunt position at the depth of 0.5m. The experimental results showed that intermittent operation mode and carbon source supplementation could significantly enhance the nitrogen removal efficiency with little influence on COD and TP removal. The average removal efficiencies for NH(3)-N and TN were 87.7 ± 1.4 and 70.1 ± 1.0%, increased by 12.5 ± 1.0 and 8.6 ± 0.7%, respectively.

  1. Enhanced Geothermal Systems Research and Development: Models of Subsurface Chemical Processes Affecting Fluid Flow

    SciTech Connect

    Moller, Nancy; Weare J. H.

    2008-05-29

    Successful exploitation of the vast amount of heat stored beneath the earth’s surface in hydrothermal and fluid-limited, low permeability geothermal resources would greatly expand the Nation’s domestic energy inventory and thereby promote a more secure energy supply, a stronger economy and a cleaner environment. However, a major factor limiting the expanded development of current hydrothermal resources as well as the production of enhanced geothermal systems (EGS) is insufficient knowledge about the chemical processes controlling subsurface fluid flow. With funding from past grants from the DOE geothermal program and other agencies, we successfully developed advanced equation of state (EOS) and simulation technologies that accurately describe the chemistry of geothermal reservoirs and energy production processes via their free energies for wide XTP ranges. Using the specific interaction equations of Pitzer, we showed that our TEQUIL chemical models can correctly simulate behavior (e.g., mineral scaling and saturation ratios, gas break out, brine mixing effects, down hole temperatures and fluid chemical composition, spent brine incompatibilities) within the compositional range (Na-K-Ca-Cl-SO4-CO3-H2O-SiO2-CO2(g)) and temperature range (T < 350°C) associated with many current geothermal energy production sites that produce brines with temperatures below the critical point of water. The goal of research carried out under DOE grant DE-FG36-04GO14300 (10/1/2004-12/31/2007) was to expand the compositional range of our Pitzer-based TEQUIL fluid/rock interaction models to include the important aluminum and silica interactions (T < 350°C). Aluminum is the third most abundant element in the earth’s crust; and, as a constituent of aluminosilicate minerals, it is found in two thirds of the minerals in the earth’s crust. The ability to accurately characterize effects of temperature, fluid mixing and interactions between major rock-forming minerals and hydrothermal and

  2. Best Practice -- Subsurface Investigations

    SciTech Connect

    Clark Scott

    2010-03-01

    These best practices for Subsurface Survey processes were developed at the Idaho National Laboratory (INL) and later shared and formalized by a sub-committee, under the Electrical Safety Committee of EFCOG. The developed best practice is best characterized as a Tier II (enhanced) survey process for subsurface investigations. A result of this process has been an increase in the safety and lowering of overall cost, when utility hits and their related costs are factored in. The process involves improving the methodology and thoroughness of the survey and reporting processes; or improvement in tool use rather than in the tools themselves. It is hoped that the process described here can be implemented at other sites seeking to improve their Subsurface Investigation results with little upheaval to their existing system.

  3. A computational-grid based system for continental drainage network extraction using SRTM digital elevation models

    NASA Technical Reports Server (NTRS)

    Curkendall, David W.; Fielding, Eric J.; Pohl, Josef M.; Cheng, Tsan-Huei

    2003-01-01

    We describe a new effort for the computation of elevation derivatives using the Shuttle Radar Topography Mission (SRTM) results. Jet Propulsion Laboratory's (JPL) SRTM has produced a near global database of highly accurate elevation data. The scope of this database enables computing precise stream drainage maps and other derivatives on Continental scales. We describe a computing architecture for this computationally very complex task based on NASA's Information Power Grid (IPG), a distributed high performance computing network based on the GLOBUS infrastructure. The SRTM data characteristics and unique problems they present are discussed. A new algorithm for organizing the conventional extraction algorithms [1] into a cooperating parallel grid is presented as an essential component to adapt to the IPG computing structure. Preliminary results are presented for a Southern California test area, established for comparing SRTM and its results against those produced using the USGS National Elevation Data (NED) model.

  4. Characterization of Microbial Communities in Coal Mine Drainage Treatment Systems With Elevated Manganese

    NASA Astrophysics Data System (ADS)

    Tan, H.; Zhang, G.; Burgos, W.

    2007-12-01

    Sediment samples were collected from two coal mine drainage treatment sites in western Pennsylvania. Both of the sites use constructed limestone beds to passively treat acidic coal mine drainage containing elevated manganese (Mn). Site #1 has influent manganese of 150 mg/L and effluent manganese between 40-100 mg/L. Site #2 has influent manganese of 20 mg/L and effluent manganese of less than 0.5 mg/L. Large quantities of black crusts were deposited throughout the beds at both sites. X-ray diffraction showed these crusts constituted of buserite, which is a layered structure manganese oxide mineral. Both culture-dependent and nucleic acid- based techniques were used to characterize the bacterial and fungal communities in these beds. 16S rRNA gene analysis showed that bacterial communities were very diverse and included Cyanobacter, Proteobacteria, Bacteroidete, Planctomyceta, Acidobacter, Actinobacter and Gemmatimonade taxa. The archaeal diversity was lower and most sequences were related to uncultivated species. Two Mn-oxidizing fungi strains were isolated from one of the sites. One of the fungi is capable of oxidizing Mn(II) at both low and netural pH (3-7) while the other fungi can only oxidze Mn(II) at circumneutral pH. 18S rRNA gene analysis showed the low pH Mn-oxidizing fungus was closely related to Menispora tortuosa, Chaetosphaeria curvispora and Kionochaeta spissa, and the circumneutral Mn-oxidizing fungus was closely related to Myrothecium verrucaria, Didymostilbe echinofibrosa and Myrothecium roridum.

  5. Laboratory Evaluation of Sulfur Modified Iron for Use as a Filter Material to Treat Agricultural Drainage Waters

    NASA Astrophysics Data System (ADS)

    Allred, B. J.

    2009-12-01

    Where subsurface drainage practices are employed, fertilizer nutrients and pesticides applied on farm fields and municipal locations are commonly intercepted by the buried drainage pipes and then discharged into local streams and lakes, oftentimes producing adverse environmental impacts on these surface water bodies. On-site water filter treatment systems can be employed to prevent the release of agricultural nutrients/pesticides into adjacent waterways. Sulfur modified iron is a relatively unknown industrial product that may have promise for use as a filter material to remove contaminants from subsurface drainage waters. Sulfur modified iron (SMI) is a high surface area iron powder (zero valent iron) that has been altered via chemical reaction with pure sulfur to produce a sulfur/iron surface coating on the iron particles. A laboratory investigation was conducted with contaminant removal batch tests, saturated falling-head hydraulic conductivity tests, and saturated solute transport column experiments to evaluate the feasibility for using SMI to treat subsurface drainage waters. Contaminant removal batch tests showed that three SMI samples were much more effective removing nitrate (> 94% nitrate removed) than three zero valent iron samples (< 10% nitrate removed). Batch test results additionally showed that SMI removed greater that 94% of dissolved phosphate, but was not particularly effective removing the pesticide, atrazine (< 37% atrazine removed). Hydraulic conductivity tests indicated that all three SMI samples that were evaluated had sufficient hydraulic conductivity, much greater than the 1 x 10-3 cm/s standard used for stormwater sand filters. The saturated solute transport tests confirmed that SMI can be effective removing nitrate and phosphate from drainage waters. Analysis of column effluent also showed that the large majority of nitrate removed by SMI was converted to ammonium. Consequently, these laboratory findings support the use of SMI in

  6. Subsurface Electromagnetic Target Characterization and Identification

    DTIC Science & Technology

    1979-06-01

    B. Subsurface Electromagnetic Video Pulse Radar System 5 C. The Subsurface Targets 11 D. Raw Measured Waveforms 14 E. Processed Waveforms 15 III...259 r i. I .. . . .... .. . . . . .;. . . . .. .. o _ • v . . • • • -• -. . .. -"... .. . II II LIST OF FIGURES Figure Page 1 The subsurface pulse ...7 3 Typical raw waveform received by the pulse radar system ..... ................... .i..... 9 4 Physical characteristics of the subsurface

  7. Impact of a real-time controlled wastewater subsurface drip disposal system on the selected chemical properties of a vertisol.

    PubMed

    Hea, Jiajie; Dougherty, Mark; Arriaga, Francisco J; AbdelGadir, Abdelaziz H

    2013-01-01

    The operation of onsite septic effluent disposal without considering seasonal moisture changes in drain field conditions can be a major cause of the failure of conventional septic systems. This study addressed this issue from a soil hydraulic perspective by using real-time drain field soil moisture levels to limit septic effluent disposal in a vertisol via subsurface drip irrigation. A prototype system was field-tested in a Houston clay soil and results describe the subsequent impact on selected soil chemical properties. After one year of hydraulic dosing with a synthetic wastewater, soil total carbon and nitrogen concentrations increased, but no increase in soil total phosphorus concentration was observed. Soil NO3-N leaching potential was noted, but soil NH4-N concentrations decreased, which could be ascribed to NH4-N nitrification, fixation within clay sheets and NH3 volatilization. Soil K+, Mg2+ and Na+ concentrations increased in soil layers above the drip lines, but decreased in soil layers below drip lines. Soil electrical conductivity accordingly increased in soil layers above drip lines, but the range was significantly lower than the threshold for soil salinity. Although the moisture-controlled effluent disposal strategy successfully avoided hydraulic dosing during unfavourable wet drain field conditions and prevented accumulation of soil salts in the soil profile beneath the drip lines, soil salts tended to accumulate in top soil layers. These adverse effects warrant system corrections before large-scale implementation of subsurface drip irrigation of effluent in similar vertisols.

  8. Surface, Subsurface and Atmosphere Exchanges on the Satellites of the Outer Solar System

    NASA Astrophysics Data System (ADS)

    Tobie, G.; Giese, B.; Hurford, T. A.; Lopes, R. M.; Nimmo, F.; Postberg, F.; Retherford, K. D.; Schmidt, J.; Spencer, J. R.; Tokano, T.; Turtle, E. P.

    2010-06-01

    The surface morphology of icy moons is affected by several processes implicating exchanges between their subsurfaces and atmospheres (if any). The possible exchange of material between the subsurface and the surface is mainly determined by the mechanical properties of the lithosphere, which isolates the deep, warm and ductile ice material from the cold surface conditions. Exchanges through this layer occur only if it is sufficiently thin and/or if it is fractured owing to tectonic stresses, melt intrusion or impact cratering. If such conditions are met, cryomagma can be released, erupting fresh volatile-rich materials onto the surface. For a very few icy moons (Titan, Triton, Enceladus), the emission of gas associated with cryovolcanic activity is sufficiently large to generate an atmosphere, either long-lived or transient. For those moons, atmosphere-driven processes such as cryovolcanic plume deposition, phase transitions of condensable materials and wind interactions continuously re-shape their surfaces, and are able to transport cryovolcanically generated materials on a global scale. In this chapter, we discuss the physics of these different exchange processes and how they affect the evolution of the satellites’ surfaces.

  9. Acid Mine Drainage Research in Gauteng Highlighting Impacts on Infrastructure and Innovation of Concrete-Based Remedial Systems

    NASA Astrophysics Data System (ADS)

    Diop, S.; Ekolu, S.; Azene, F.

    2013-12-01

    Acid mine drainage (AMD) is presently one of the most important environmental problems in in the densely populated Gauteng Province, South Africa. The threat of acid mine drainage has demanded short-term interventions (some of which are being implemented by government) but more importantly sustainable long-term innovative solutions. There have been moments of public apprehension with some media reports dubbing the current scenario as a future 'nightmare of biblical proportions' and 'South Africa's own Chernobyl' that could cause dissolving of concrete foundations of buildings and reinforcement steel, leading to collapse of structures. In response to the needs of local and provincial authorities, this research was conducted to (1) generate scientific understanding of the effects of AMD on infrastructure materials and structures, and (2) propose innovative long-term remedial systems based on cementitious materials for potential AMD treatment applications of engineering scale. Two AMD solutions from the goldfields and two others from the coalfields were used to conduct corrosion immersion tests on mild steel, stainless steel, mortars, pastes and concretes. Results show that AMD water from the gold mines is more corrosive than that from the coal mines, the corrosion rate of the former being about twice that of the latter. The functionality of metal components of mild steel can be expected to fail within one month of exposure to the mine water. The investigation has also led to development of a pervious concrete filter system of water-cement ratio = 0.27 and cement content = 360 kg/m3, to be used as a permeable reactive barrier for AMD treatment. Early results show that the system was effective in removing heavy metal contaminants with removal levels of 30% SO4, 99% Fe, 50-83% Mn, 85% Ca, and 30% TDS. Further work is on-going to improve and optimise the system prior to field demonstration studies.

  10. Subsurface thermal regime to delineate the paleo-groundwater flow system in an arid area, Al Kufra, Libya

    NASA Astrophysics Data System (ADS)

    Salem, Zenhom El-Said

    2016-12-01

    The purpose of this study was to understand the groundwater flow system in Al Kufra basin, Libya, as a case study of arid areas using subsurface temperature. The temperature-depth profiles and water levels were measured in eight boreholes in the area. Well 6 is considered a recharge type profile with low geothermal gradient (0.0068 °C/m) and an estimated paleo-temperature around 19.5 °C. The other profiles are of discharge type with higher geothermal gradient (0.0133 to 0.0166 °C/m). The constructed horizontal 2D distribution maps of the hydraulic heads and the subsurface temperature measurements reveal that the main recharge area is located to the south with low temperature while the main discharge area is located to the north with higher temperature. Vertical 2D distribution maps show that location of well 4 has low hydraulic heads and higher temperature indicating that the fault defined in the area may have affected the groundwater flow system. The estimated groundwater flux ranges from 0.001 to 0.1 mm/day for the recharge area and from -0.3 to -0.7 mm/day in average in the discharge area.

  11. USGS develops a drainage-based system to track ANS introductions

    USGS Publications Warehouse

    Fuller, Pam L.

    1999-01-01

    The U.S. Geological Survey (USGS) Nonindigenous Aquatic Species (NAS) Program has tracked the distribution of introduced species for more than 20 years. This effort began with foreign fishes in Florida and later expanded to include aquatic nuisance species nationwide. The tracking database contains locational and temporal data for introductions and spread. This data is generally derived from literature, museum collections, state monitoring programs, and reports from professionals at state and federal agencies. Analysis of this data can be helpful in displaying any patterns that may be present in introductions of aquatic nuisance species and developing a management plan to prevent spread. To produce maps and perform analysis, all data are referenced geographically at the finest scale possible (state, county, drainage, waterbody, point). Data reported in the literature range from state or regional lists of introduced species to exact time, date, and location of collections or releases. Often, vague locality reports make it difficult to obtain accurate answers in fine-scale analysis.

  12. Reactive Transport Modeling of Subsurface Arsenic Removal Systems in Rural Bangladesh

    NASA Astrophysics Data System (ADS)

    Bakker, M.; Rahman, M. M.; van Breukelen, B. M.; Ahmed, K. M.

    2014-12-01

    Elevated concentrations of arsenic (As) in the groundwater of the shallow aquifers of Bangladesh are a major public health concern. Subsurface Arsenic Removal (SAR) is a relatively new treatment option that can potentially be a cost effective method for arsenic removal for community-based drinking water supplies. The basic idea of SAR is to extract water, aerate it, and re-inject it, after which groundwater with reduced arsenic concentrations may be extracted. The main process for As reduction is sorption to Hydrous Ferric Oxides (HFO) that forms after injection of the aerated water. The purpose of this poster is to investigate the major geochemical processes responsible for the (im)mobilization of As during SAR operation. SAR was applied at a test site in Muradnagar upazila in Comilla district about 100 km southeast of Dhaka in Bangladesh. Multiple extraction/aeration/re-injection cycles were performed and water samples were analyzed. A PHREEQC reactive transport model (RTM) was used in a radial flow setting to try to reproduce the measurements. Kinetic oxidation/dissolution reactions, cation exchange, and surface complexation were simulated. The simulation of different reactions enables the possibility to discern the reaction parameters involved in the im(mobilization) of As. The model fit has reasonable agreement with the observed data for major ions and trace elements. The model suggests an increasing sorption capacity due to the gradual development of HFO precipitates resulting from the injection phases. Modeled breakthrough curves of As, Fe(II), and Mn, match the measured increase of As, Fe(II), and Mn removal with successive cycles. The model illustrates that the pH of groundwater during SAR operation has a great impact on As sorption in the subsurface. The surface complexation modeling suggests that competitive displacement of As by H4SiO4 is an important factor limiting As removal during SAR operation.

  13. EOS7CA Version 1.0: TOUGH2 Module for Gas Migration in Shallow Subsurface Porous Media Systems

    SciTech Connect

    Oldenburg, Curtis M.

    2015-06-22

    EOS7CA is a TOUGH2 module for mixtures of a non-condensible gas (NCG) and air (with or without a gas tracer), an aqueous phase, and water vapor. The user can select the NCG as being CO2, N2, or CH4. EOS7CA uses a cubic equation of state with a multiphase version of Darcy’s Law to model flow and transport of gas and aqueous phase mixtures over a range of pressures and temperatures appropriate to shallow subsurface porous media systems. The limitation to shallow systems arises from the use of Henry’s Law for gas solubility which is appropriate for low pressures but begins to over-predict solubility starting at pressures greater than approximately 1 MPa (10 bar). The components modeled in EOS7CA are water, brine, NCG, gas tracer, air, and optional heat.

  14. Acid mine drainage

    USGS Publications Warehouse

    Bigham, Jerry M.; Cravotta, Charles A.

    2016-01-01

    Acid mine drainage (AMD) consists of metal-laden solutions produced by the oxidative dissolution of iron sulfide minerals exposed to air, moisture, and acidophilic microbes during the mining of coal and metal deposits. The pH of AMD is usually in the range of 2–6, but mine-impacted waters at circumneutral pH (5–8) are also common. Mine drainage usually contains elevated concentrations of sulfate, iron, aluminum, and other potentially toxic metals leached from rock that hydrolyze and coprecipitate to form rust-colored encrustations or sediments. When AMD is discharged into surface waters or groundwaters, degradation of water quality, injury to aquatic life, and corrosion or encrustation of engineered structures can occur for substantial distances. Prevention and remediation strategies should consider the biogeochemical complexity of the system, the longevity of AMD pollution, the predictive power of geochemical modeling, and the full range of available field technologies for problem mitigation.

  15. Testing Novel CR-39 Detector Deployment System For Identification of Subsurface Fractures, Soda Springs, ID

    SciTech Connect

    McLing, Travis; Carpenter, Michael; Brandon, William; Zavala, Bernie

    2015-06-01

    The Environmental Protection Agency (EPA) has teamed with Battelle Energy Alliance, LLC (BEA) at Idaho National Laboratory (INL) to facilitate further testing of geologic-fracture-identification methodology at a field site near the Monsanto Superfund Site located in Soda Springs, Idaho. INL has the necessary testing and technological expertise to perform this work. Battelle Memorial Institute (BMI) has engaged INL to perform this work through a Work for Others (WFO) Agreement. This study continues a multi-year collaborative effort between INL and EPA to test the efficacy of using field deployed Cr-39 radon in soil portals. This research enables identification of active fractures capable of transporting contaminants at sites where fractures are suspected pathways into the subsurface. Current state of the art methods for mapping fracture networks are exceedingly expensive and notoriously inaccurate. The proposed WFO will evaluate the applicability of using cheap, readily available, passive radon detectors to identify conductive geologic structures (i.e. fractures, and fracture networks) in the subsurface that control the transport of contaminants at fracture-dominated sites. The proposed WFO utilizes proven off-the-shelf technology in the form of CR-39 radon detectors, which have been widely deployed to detect radon levels in homes and businesses. In an existing collaborative EPA/INL study outside of this workscope,. CR-39 detectors are being utilized to determine the location of active transport fractures in a fractured granitic upland adjacent to a landfill site at the Fort Devens, MA that EPA-designated as National Priorities List (NPL) site. The innovative concept of using an easily deployed port that allows the CR-39 to measure the Rn-222 in the soil or alluvium above the fractured rock, while restricting atmospheric Rn-222 and soil sourced Ra from contaminating the detector is unique to INL and EPA approach previously developed. By deploying a series of these

  16. Hydrological Modeling of Storm Water Drainage System due to Frequent and Intense Precipitation of Dhaka city using Storm Water Management Model (SWMM)

    NASA Astrophysics Data System (ADS)

    Hossain, S., Jr.

    2015-12-01

    Rainfall induced flooding during rainy season is a regular phenomenon in Dhaka City. Almost every year a significant part of the city suffers badly with drainage congestion. There are some highly dense areas with lower ground elevation which submerge under water even with an intense precipitation of few hours. The higher areas also suffer with the drainage problem due to inadequate maintenance of the system and encroachment or illegal filling up of the drainage canals and lakes. Most part of the city suffered from long term urban flooding during historical extreme rainfall events in September 2004, 2007 and July 2009. The situation is likely to worsen in the future due to Climate Change, which may lead to more frequent and intense precipitation. To assess the major and minor drainage systems and elements of the urban basins using the hydrodynamic modelling and, through this, identifying the flooding events and areas, taking into account the current situation and future flood or drainage scenarios. Stormwater modeling has a major role in preventing issues such as flash floods and urban water-quality problems. Stormwater models of a lowered spatial resolution would thus appear valuable if only their ability to provide realistic results could be proved. The present scenario of urban morphology of Dhaka city and existing drainage system is complex for hydrological and hydrodynamic modeling. Furthermore limitations of background data and uncertain future urban scenarios may confine the potential outputs of a model. Although several studies were carried out including modeling for drainage master planning, a detail model for whole DAP (Detaile Area Plan) of Dhaka city area is not available. The model developed under this study is covering the existing drainage system in the study area as well as natural flows in the fringe area. A good number of models are available for hydrological and hydraulic analysis of urban areas. These are MIKE 11, MOUSE, HEC-RAS, HEC HMS and EPA

  17. Fluid Flow along Venous Adventitia in Rabbits: Is It a Potential Drainage System Complementary to Vascular Circulations?

    PubMed Central

    Li, Hong-yi; Chen, Min; Yang, Jie-fu; Yang, Chong-qing; Xu, Liang; Wang, Fang; Tong, Jia-bin; Lv, You; Suonan, Caidan

    2012-01-01

    Background Our previous research and other studies with radiotracers showed evidence of a centripetal drainage pathway, separate from blood or lymphatic vessels, that can be visualized when a small amount of low molecular weight tracer is injected subcutaneously into a given region on skin of humans. In order to further characterize this interesting biological phenomenon, animal experiments are designed to elucidate histological and physiologic characteristics of these visualized pathways. Methods Multiple tracers are injected subcutaneously into an acupuncture point of KI3 to visualize centripetal pathways by magnetic resonance imaging or fluorescein photography in 85 healthy rabbits. The pathways are compared with venography and indirect lymphangiography. Fluid flow through the pathways is observed by methods of altering their hydrated state, hydrolyzing by different collagenases, and histology is elucidated by optical, fluorescein and electron microscopy. Results Histological and magnetic imaging examinations of these visualized pathways show they consist of perivenous loose connective tissues. As evidenced by examinations of tracers’ uptake, they appear to function as a draining pathway for free interstitial fluid. Fluorescein sodium from KI3 is found in the pathways of hind limbs and segments of the small intestines, partial pulmonary veins and results in pericardial effusion, suggesting systematical involvement of this perivenous pathway. The hydraulic conductivity of these pathways can be compromised by the collapse of their fiber-rich beds hydrolyzed by either of collagenase type I, III, IV or V. Conclusions The identification of pathways comprising perivenous loose connective tissues with a high hydraulic conductivity draining interstitial fluid in hind limbs of a mammal suggests a potential drainage system complementary to vascular circulations. These findings may provide new insights into a systematically distributed collagenous connective tissue with

  18. Nanoscale study of As biomineralization in an acid mine drainage system

    NASA Astrophysics Data System (ADS)

    Benzerara, K.; Morin, G.; Yoon, T. H.; Miot, J.; Tyliszczak, T.; Casiot, C.; Bruneel, O.; Farges, F.; Brown, G. E.

    2008-08-01

    Spatial and seasonal variations of the oxidation of Fe(II) and As(III) have been previously documented in the Carnoulès (Gard, France) Acid Mine Drainage (AMD) by bulk analyses. These variations may be correlated with the variations in the activity of indigenous As(III)- and Fe(II)-oxidizing bacteria living in the As-rich Carnoulès water. The activity of these bacteria indeed plays an important role in the nature and composition of the solid phases that sequester arsenic at this site. In order to better understand the interactions of microbes with Fe and As in the Carnoulès AMD, we combined Transmission Electron Microscopy (TEM) and Scanning Transmission X-ray Microscopy (STXM) to collect near-edge X-ray absorption fine structure (NEXAFS) spectra at high spatial and energy resolution and to perform high spatial resolution imaging at the 30-50 nm scale. Spectromicroscopy was performed at the C K-edge, Fe L 2,3-edge, and As L 2,3-edge, which allowed us to locate living and/or mineralized bacterial cells and to characterize Fe and As oxidation states in the vicinity of those cells. TEM was used to image the same areas, providing higher resolution images and complementary crystallographic and compositional information through electron diffraction and EDXS analysis. This approach provides unique information on heterogeneous geochemical processes that occur in a complex microbial community in an AMD environment at the micrometer and submicrometer-scale. Bacterial cells in the Carnoulès AMD were frequently associated with mineral precipitates, and a variety of biomineralization patterns were observed. While many mineral precipitates were not associated with bacterial cells, they were associated with pervasive organic carbon. Finally, abundant biomineralized organic vesicles were observed in the Carnoulès AMD. Such vesicles may have been overlooked in highly mineralized extreme environments in the past and may represent an important component in a common

  19. Drainage Areas of Selected Streams in Virginia

    USGS Publications Warehouse

    Hayes, Donald C.; Wiegand, Ute

    2006-01-01

    Drainage areas were determined for more than 1,600 basins in the three major river basins of Virginia -- the North Atlantic Slope, South Atlantic Slope, and Ohio River Basins. Drainage areas range from 0.004 square mile to 7,866 square miles. A geographic information system was used to digitize and store data associated with the drainage basins. Drainage divides were digitized from digital U.S. Geological Survey 7.5-minute, 1:24,000-scale, topographic quadrangles using procedures recommended by the Subcommittee on Hydrology, Federal Interagency River Basin Committee. Digital drainage basins were quality assured, polygons of the closed drainage basins were generated, and drainage areas were computed.

  20. Shallow subsurface morpho-tectonics at the Northern offshore Sumatra subduction system using high resolution reflection and refraction seismics

    NASA Astrophysics Data System (ADS)

    Ghosal, D.; Dibakar Ghosal*, S. C. Singh, A. P. S. Chauhan, H. Carton, N. D. Hananto

    2011-12-01

    The oblique subduction of Indo-Australian plate below the Eurosian plate regulates the subsurface geology of the Sumatra subduction system from south to north. Although many geological, geophysical and geodetic studies have been carried over since several decades nevertheless a high resolution subsurface image describing the detailed structural features over the Northern Sumatra is still missing. To scrutinize the northern part of this subduction system we had carried out a multi channel seismic (MCS) and OBS survey using a 12 km long streamer and 56 ocean bottom seismometers in 2006 and procured a high resolution deep seismic reflection and refraction data over a 500 km long profile mapping the whole subduction setting from the subduction front, forearc high and basin, Sumatra platform, Sumatra fault and volcanic arc. The acoustic basement along the profile is very complex because of its extremities lies in a range of 300 m to 5000 m. In order to overcome the imaging-intricacies caused due to the abrupt changes of water depth, we have downward continued the 12 km streamer data to the seafloor, which provides refraction arrivals from near zero offsets to 12 km, and subsequently a high-resolution travel time tomography keeping node spacing of 50m x 50m has accomplished to procure a detail velocity structure along the profile. We have conducted our analysis in two important areas at northern offshore Sumatra: (1) subduction front and accretionary settings and (2) forearc high and West Anadman Fault. Our main goal lies to observe the nature of shallow subsurface velocity distribution over these regions. Tomographic result of the subduction front demonstrates the changes in velocity gradient along up-dip. The 1D velocity gradients become shallower toward the subduction trench inferring the fact of lithification of accreted sediments around the accretionary wedge. At the forearc high adjacent to the Aceh basin a pile of 1 km thick low velocity sediments is underlain by

  1. Plant development and yield of four sugarcane varieties irrigated by a subsurface drip irrigation system in Campinas, Brazil

    NASA Astrophysics Data System (ADS)

    Silva, André Luiz Barros de O.; Célia de Matos Pires, Regina; Yukitaka Pessinati Ohashi, Augusto; Vasconcelos Ribeiro, Rafael; Landell, Marcos Guimarães de Andrade; Aparecida Creste Dias de Souza, Silvana

    2013-04-01

    The biofuel production is a growing concern on modern society due to the agricultural sustainability, in which both food and energy supply should be taken into account. The agroclimatic zoning indicates that sugarcane expansion in Brazil can only take place in marginal lands, where water deficit occurs and irrigation is necessary. The use of subsurface drip irrigation (SDI) in sugarcane cultivation is an interesting cultural practice to improve production and allow cultivation in marginal lands due to water deficit conditions or to attain high yield and to increase longevity of plants. In this context it is necessary to investigate responses of different varieties to water supply. The aim of this work was to evaluate the plant development and yield of four sugarcane varieties irrigated by a subsurface drip irrigation system in Campinas, Brazil in the 1st cane ratoon cycle. The field experiment was carried out in Campinas SP Brazil, with IACSP95-5000, IACSP94-2094, IACSP94-2101 and SP79-1011 cultivars in the 1st cane ratoon cycle, from January (after the harvest of cane plant cycle) to October (harvest the 1st cane ratoon cycle). The plant spacing was 1.5 m between rows. Each cultivar was planted in an area of 0.4 hectares. The irrigation was done by a subsuperficial drip system with one drip line in each plant row installed at 0.25 m deep. During the 1st cane ratoon cycle the parameters were analysed on the 33rd, 123rd, 185th and 277th day. The analysed parameters were: plant yield (m), leaf area index (LAI) and yield (tons per hectare). According to the results from the second sampling (123rd day) the varieties IACSP95-5000 and IACSP94-2101 showed higher plant height when compared to the other varieties. However, from the third sampling (185th day) on the IACSP95-5000 variety grew considerably taller than the other varieties. The varieties SP79-1011and IACSP94-2101 presented lower values of LAI throughout the crop cycle when compared to other varieties. But on the

  2. Effectiveness of highway-drainage systems in preventing contamination of ground water by road salt, Route 25, southeastern Massachusetts; description of study area, data collection programs, and methodology

    USGS Publications Warehouse

    Church, P.E.; Armstrong, D.S.; Granato, G.E.; Stone, V.J.; Smith, K.P.; Provencher, P.L.

    1996-01-01

    Four test sites along a 7-mile section of Route 25 in southeastern Massachusetts, each representing a specific highway-drainage system, were instrumented to determine the effectiveness of the drainage systems in preventing contamination of ground water by road salt. One of the systems discharges highway runoff onsite through local drainpipes. The other systems use trunkline drainpipes through which runoff from highway surfaces, shoulders, and median strips is diverted and discharged into either a local stream or a coastal waterway. Route 25 was completed and opened to traffic in the summer of 1987. Road salt was first applied to the highway in the winter of 1987-88. The study area is on a thick outwash plain composed primarily of sand and gravel. Water-table depths range from 15 to 60 feet below land surface at the four test sites. Ground-water flow is in a general southerly direction, approximately perpendicular to the highway. Streamflow in the study area is controlled primarily by ground-water discharge. Background concentrations of dissolved chloride, sodium, and calcium-the primary constituents of road salt-are similar in ground water and surface water and range from 5 to 20, 5 to 10, and 1 to 5 milligrams per liter, respectively. Data-collection programs were developed for monitoring the application of road salt to the highway, the quantity of road-salt water entering the ground water, diverted through the highway-drainage systems, and entering a local stream. The Massachusetts Highway Department monitored road salt applied to the highway and reported these data to the U.S. Geological Survey. The U.S. Geological Survey designed and operated the ground-water, highway- drainage, and surface-water data-collection programs. A road-salt budget will be calculated for each test site so that the effectiveness of the different highway-drainage systems in preventing contamination of ground water by road salt can be determined.

  3. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system.

    PubMed

    Ohtomo, Yoko; Ijiri, Akira; Ikegawa, Yojiro; Tsutsumi, Masazumi; Imachi, Hiroyuki; Uramoto, Go-Ichiro; Hoshino, Tatsuhiko; Morono, Yuki; Sakai, Sanae; Saito, Yumi; Tanikawa, Wataru; Hirose, Takehiro; Inagaki, Fumio

    2013-01-01

    Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ(13)Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate.

  4. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system

    PubMed Central

    Ohtomo, Yoko; Ijiri, Akira; Ikegawa, Yojiro; Tsutsumi, Masazumi; Imachi, Hiroyuki; Uramoto, Go-Ichiro; Hoshino, Tatsuhiko; Morono, Yuki; Sakai, Sanae; Saito, Yumi; Tanikawa, Wataru; Hirose, Takehiro; Inagaki, Fumio

    2013-01-01

    Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0–100 MPa) and temperature (0–70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ13Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate. PMID

  5. Results of a Conceptual Systems Analysis of Systems for 200 m Deep Sampling of the Martian Subsurface

    NASA Astrophysics Data System (ADS)

    Blacic, J.; Dreesen, D.; Mockler, T.

    2000-01-01

    Recent robotic orbital and lander missions at Mars are part of a renewed campaign of exploration that seeks to build on the early successes of the Viking program. Current plans feature a vigorous series of orbital, surface and subsurface robotic missions with a probable return of a small number of atmosphere, rock and soil samples to Earth, and culminate in human exploration before the end of the second decade of the new millennium. The latest discoveries of this program are lending increasing support to models of a water-rich Martian history in which most of the remaining water is now thought to reside in the subsurface. Furthermore, the top-level goal of seeking evidence of extant or fossil life on Mars has evolved a strategy of "follow the water", since experience shows that life on Earth seems to require the presence of liquid water. In addition, water, if found, would be the most valuable in situ resource that could be developed to support manned exploration of Mars. These developments have led to a compelling argument for deep subsurface in situ measurements and sampling on Mars, a challenge never faced by planetary science on any body other than the Earth.

  6. Brine migration resulting from pressure increases in a layered subsurface system

    NASA Astrophysics Data System (ADS)

    Delfs, Jens-Olaf; Nordbeck, Johannes; Bauer, Sebastian

    2016-04-01

    Brine originating from the deep subsurface impairs parts of the freshwater resources in the North German Basin. Some of the deep porous formations (esp. Trias and Jurassic) exhibit considerable storage capacities for waste fluids (CO2, brine from oil production or cavern leaching), raising concerns among water providers that this type of deep subsurface utilization might impair drinking water supplies. On the one hand, overpressures induced by fluid injections and the geothermal gradient support brine migration from deep into shallow formations. On the other hand, the rising brine is denser than the surrounding less-saline formation waters and, therefore, tends to settle down. Aim of this work is to investigate the conditions under which pressurized formation brine from deep formations can reach shallow freshwater resources. Especially, the role of intermediate porous formations between the storage formation and the groundwater is studied. For this, complex thermohaline simulations using a coupled numerical process model are necessary and performed in this study, in which fluid density depends on fluid pressure, temperature and salt content and the governing partial differential equations are coupled. The model setup is 2D and contains a hypothetic series of aquifers and barriers, each with a thickness of 200 m. Formation pressure is increased at depths of about 2000 m in proximity to a salt wall and a permeable fault. The domain size reaches up to tens of kilometers horizontally to the salt wall. The fault connects the injection formation and the freshwater aquifer such that conditions can be considered as extremely favorable for induced brine migration (worst case scenarios). Brine, heat, and salt fluxes are quantified with reference to hydraulic permeabilities, storage capacities (in terms of domain size), initial salt and heat distribution, and operation pressures. The simulations reveal the development of a stagnation point in the fault region in each

  7. Reactive transport modeling of subsurface arsenic removal systems in rural Bangladesh.

    PubMed

    Rahman, M M; Bakker, M; Patty, C H L; Hassan, Z; Röling, W F M; Ahmed, K M; van Breukelen, B M

    2015-12-15

    Subsurface Arsenic Removal (SAR) is a technique for in-situ removal of arsenic from groundwater. Extracted groundwater is aerated and re-injected into an anoxic aquifer, where the oxygen in the injected water reacts with ferrous iron in the aquifer to form hydrous ferric oxide (HFO). Subsequent extraction of groundwater contains temporarily lower As concentrations, because As sorbs onto the HFO. Injection, storage, and extraction together is called a cycle. A reactive transport model (RTM) was developed in PHREEQC to determine the hydrogeochemical processes responsible for As (im)mobilization during experimental SAR operation performed in Bangladesh. Oxidation of Fe(II) and As(III) were modeled using kinetic-rate expressions. Cation exchange, precipitation of HFO, and surface complexation, were modeled as equilibrium processes. A best set of surface complexation reactions and corresponding equilibrium constants was adopted from previous studies to simulate all 20 cycles of a SAR experiment. The model gives a reasonable match with observed concentrations of different elements in the extracted water (e.g., the r(2) value of As was 0.59 or higher). As concentrations in the extracted water are governed by four major processes. First, As concentration decreases in response to the elevated pH of injection water and likewise increases when native neutral pH groundwater flows in. Second, the sorption capacity for As increases due to the gradual buildup of HFO. Third, As sorption is enhanced by preferential removal of As(V). Fourth, competitive sorption of Si limits the capacity of freshly precipitated HFO for As sorption. Transferability of the developed reactive transport model was demonstrated through successful application of the model, without further calibration, to two additional SAR sites in Bangladesh. This gives confidence that the model could be useful to assess potential SAR performance at locations in Bangladesh based on local hydrogeochemical conditions.

  8. Drainage-system development in consecutive melt seasons at a polythermal, Arctic glacier, evaluated by flow-recession analysis and linear-reservoir simulation.

    PubMed

    Hodgkins, Richard; Cooper, Richard; Tranter, Martyn; Wadham, Jemma

    2013-07-26

    [1] The drainage systems of polythermal glaciers play an important role in high-latitude hydrology, and are determinants of ice flow rate. Flow-recession analysis and linear-reservoir simulation of runoff time series are here used to evaluate seasonal and inter-annual variability in the drainage system of the polythermal Finsterwalderbreen, Svalbard, in 1999 and 2000. Linear-flow recessions are pervasive, with mean coefficients of a fast reservoir varying from 16 (1999) to 41 h (2000), and mean coefficients of an intermittent, slow reservoir varying from 54 (1999) to 114 h (2000). Drainage-system efficiency is greater overall in the first of the two seasons, the simplest explanation of which is more rapid depletion of the snow cover. Reservoir coefficients generally decline during each season (at 0.22 h d(-1) in 1999 and 0.52 h d(-1) in 2000), denoting an increase in drainage efficiency. However, coefficients do not exhibit a consistent relationship with discharge. Finsterwalderbreen therefore appears to behave as an intermediate case between temperate glaciers and other polythermal glaciers with smaller proportions of temperate ice. Linear-reservoir runoff simulations exhibit limited sensitivity to a relatively wide range of reservoir coefficients, although the use of fixed coefficients in a spatially lumped model can generate significant subseasonal error. At Finsterwalderbreen, an ice-marginal channel with the characteristics of a fast reservoir, and a subglacial upwelling with the characteristics of a slow reservoir, both route meltwater to the terminus. This suggests that drainage-system components of significantly contrasting efficiencies can coexist spatially and temporally at polythermal glaciers.

  9. Drainage-system development in consecutive melt seasons at a polythermal, Arctic glacier, evaluated by flow-recession analysis and linear-reservoir simulation

    PubMed Central

    Hodgkins, Richard; Cooper, Richard; Tranter, Martyn; Wadham, Jemma

    2013-01-01

    [1] The drainage systems of polythermal glaciers play an important role in high-latitude hydrology, and are determinants of ice flow rate. Flow-recession analysis and linear-reservoir simulation of runoff time series are here used to evaluate seasonal and inter-annual variability in the drainage system of the polythermal Finsterwalderbreen, Svalbard, in 1999 and 2000. Linear-flow recessions are pervasive, with mean coefficients of a fast reservoir varying from 16 (1999) to 41 h (2000), and mean coefficients of an intermittent, slow reservoir varying from 54 (1999) to 114 h (2000). Drainage-system efficiency is greater overall in the first of the two seasons, the simplest explanation of which is more rapid depletion of the snow cover. Reservoir coefficients generally decline during each season (at 0.22 h d−1 in 1999 and 0.52 h d−1 in 2000), denoting an increase in drainage efficiency. However, coefficients do not exhibit a consistent relationship with discharge. Finsterwalderbreen therefore appears to behave as an intermediate case between temperate glaciers and other polythermal glaciers with smaller proportions of temperate ice. Linear-reservoir runoff simulations exhibit limited sensitivity to a relatively wide range of reservoir coefficients, although the use of fixed coefficients in a spatially lumped model can generate significant subseasonal error. At Finsterwalderbreen, an ice-marginal channel with the characteristics of a fast reservoir, and a subglacial upwelling with the characteristics of a slow reservoir, both route meltwater to the terminus. This suggests that drainage-system components of significantly contrasting efficiencies can coexist spatially and temporally at polythermal glaciers. PMID:25598557

  10. A New Automatic Subsurface Gas Monitoring System for Seismogeochemical Studies, Installed in Haruno Borehole, Shizuoka Prefecture, Central Japan

    NASA Astrophysics Data System (ADS)

    Miyakawa, Kazuya; Takama, Ruka; Kawabe, Iwao; Kariya, Shinnichi; Yamauchi, Tsuneo

    2010-12-01

    The results of subsurface gas monitoring by application of gas chromatography (GC) to the gas composition of bubbles associated with groundwater for seismogeochemical studies are reported. An automated gas monitoring system was used to determine gas compositions in a 500-m borehole at the Haruno Crustal Movement Observation Site (HOS), central Japan during period 1, from December 1999 to December 2000. The average ± two standard deviation (2SD) compositions of gases in this period were He = 82 ± 29 ppmV, H2 = 170 ± 62 ppmV, Ar = 0.05 ± 0.07%, N2 = 50 ± 8%, and CH4 = 45 ± 6%. A new automated gas monitoring system equipped with a micro-GC was installed in the borehole at the HOS, and gas bubbles from the borehole were monitored during period 2, from December 2006 to March 2007. The average ± two standard deviation (2SD) compositions of gases in this period were He = 8 ± 7 ppmV, H2 = 13 ± 15 ppmV, Ar = 0.6 ± 0.3%, N2 = 66 ± 7%, and CH4 = 14 ± 14%. The gas concentration ratios (He/Ar, H2/Ar, N2/Ar, and CH4/Ar) fluctuated significantly over time and repeatedly showed abrupt spike-like increases during period 2. The gas compositions obtained in period 1 and 2 were markedly different. Over the period from 2006 to 2007, the gas bubbles were depleted in He, H2, and CH4 of deep origin, but enriched in Ar and N2 of atmospheric origin. This difference can be interpreted as being due to an irreversible change of the aquifer/gas system. The present deep component in the HOS gas is estimated to have composition He = 63 ppmV, H2 = 37 ppmV, Ar = 0.17%, N2 = 63%, and CH4 = 37%. The new monitoring system is able to analyze the gas composition using a smaller volume of sample gas and with greater precision than the previous system. During the 3-month monitoring period 2, the separation capacity of the capillary column of the micro-GC was sufficiently maintained to determine gas-chromatographic peak areas for the five gaseous species examined. This study confirms that the

  11. Subsurface Ice Probe

    NASA Technical Reports Server (NTRS)

    Hecht, Michael; Carsey, Frank

    2005-01-01

    The subsurface ice probe (SIPR) is a proposed apparatus that would bore into ice to depths as great as hundreds of meters by melting the ice and pumping the samples of meltwater to the surface. Originally intended for use in exploration of subsurface ice on Mars and other remote planets, the SIPR could also be used on Earth as an alternative to coring, drilling, and melting apparatuses heretofore used to sample Arctic and Antarctic ice sheets. The SIPR would include an assembly of instrumentation and electronic control equipment at the surface, connected via a tether to a compact assembly of boring, sampling, and sensor equipment in the borehole (see figure). Placing as much equipment as possible at the surface would help to attain primary objectives of minimizing power consumption, sampling with high depth resolution, and unobstructed imaging of the borehole wall. To the degree to which these requirements would be satisfied, the SIPR would offer advantages over the aforementioned ice-probing systems.

  12. Abandoned mine drainage in the Swatara Creek Basin, southern anthracite coalfield, Pennsylvania, USA: 2. performance of treatment systems

    USGS Publications Warehouse

    Cravotta, Charles A.

    2010-01-01

    A variety of passive and semi-passive treatment systems were constructed by state and local agencies to neutralize acidic mine drainage (AMD) and reduce the transport of dissolved metals in the upper Swatara Creek Basin in the Southern Anthracite Coalfield in eastern Pennsylvania. To evaluate the effectiveness of selected treatment systems installed during 1995–2001, the US Geological Survey collected water-quality data at upstream and downstream locations relative to each system eight or more times annually for a minimum of 3 years at each site during 1996–2007. Performance was normalized among treatment types by dividing the acid load removed by the size of the treatment system. For the limestone sand, open limestone channel, oxic limestone drain, anoxic limestone drain (ALD), and limestone diversion well treatment systems, the size was indicated by the total mass of limestone; for the aerobic wetland systems, the size was indicated by the total surface area of ponds and wetlands. Additionally, the approximate cost per tonne of acid treated over an assumed service life of 20 years was computed. On the basis of these performance metrics, the limestone sand, ALD, oxic limestone drain, and limestone diversion wells had similar ranges of acid-removal efficiency and cost efficiency. However, the open limestone channel had lower removal efficiency and higher cost per ton of acid treated. The wetlands effectively attenuated metals transport but were relatively expensive considering metrics that evaluated acid removal and cost efficiency. Although the water-quality data indicated that all treatments reduced the acidity load from AMD, the ALD was most effective at producing near-neutral pH and attenuating acidity and dissolved metals. The diversion wells were effective at removing acidity and increasing pH of downstream water and exhibited unique potential to treat moderate to high flows associated with storm flow conditions.

  13. Final Report DE-EE0005380: Assessment of Offshore Wind Farm Effects on Sea Surface, Subsurface and Airborne Electronic Systems

    SciTech Connect

    Ling, Hao; Hamilton, Mark F.; Bhalla, Rajan; Brown, Walter E.; Hay, Todd A.; Whitelonis, Nicholas J.; Yang, Shang-Te; Naqvi, Aale R.

    2013-09-30

    Offshore wind energy is a valuable resource that can provide a significant boost to the US renewable energy portfolio. A current constraint to the development of offshore wind farms is the potential for interference to be caused by large wind farms on existing electronic and acoustical equipment such as radar and sonar systems for surveillance, navigation and communications. The US Department of Energy funded this study as an objective assessment of possible interference to various types of equipment operating in the marine environment where offshore wind farms could be installed. The objective of this project was to conduct a baseline evaluation of electromagnetic and acoustical challenges to sea surface, subsurface and airborne electronic systems presented by offshore wind farms. To accomplish this goal, the following tasks were carried out: (1) survey electronic systems that can potentially be impacted by large offshore wind farms, and identify impact assessment studies and research and development activities both within and outside the US, (2) engage key stakeholders to identify their possible concerns and operating requirements, (3) conduct first-principle modeling on the interactions of electromagnetic signals with, and the radiation of underwater acoustic signals from, offshore wind farms to evaluate the effect of such interactions on electronic systems, and (4) provide impact assessments, recommend mitigation methods, prioritize future research directions, and disseminate project findings. This report provides a detailed description of the methodologies used to carry out the study, key findings of the study, and a list of recommendations derived based the findings.

  14. Subsurface connection methods for subsurface heaters

    DOEpatents

    Vinegar, Harold J.; Bass, Ronald Marshall; Kim, Dong Sub; Mason, Stanley Leroy; Stegemeier, George Leo; Keltner, Thomas Joseph; Carl, Jr., Frederick Gordon

    2010-12-28

    A system for heating a subsurface formation is described. The system includes a first elongated heater in a first opening in the formation. The first elongated heater includes an exposed metal section in a portion of the first opening. The portion is below a layer of the formation to be heated. The exposed metal section is exposed to the formation. A second elongated heater is in a second opening in the formation. The second opening connects to the first opening at or near the portion of the first opening below the layer to be heated. At least a portion of an exposed metal section of the second elongated heater is electrically coupled to at least a portion of the exposed metal section of the first elongated heater in the portion of the first opening below the layer to be heated.

  15. A web accessible scientific workflow system for transparent and reproducible generation of information on subsurface processes from autonomously sensed data

    NASA Astrophysics Data System (ADS)

    Versteeg, R.; Richardson, A.; Thomas, S.; Lu, B.; Neto, J.; Wheeler, M.; Rowe, T.; Parashar, M.; Ankeny, M.

    2005-12-01

    Information on subsurface processes is required for a broad range of applications, including site remediation, groundwater management, fossil fuel production and CO2 sequestration. Data on these processes is obtained from diverse sensor networks, includes physical, hydrological and chemical sensors and semi permanent geophysical sensors (mainly seismic and resistivity). Currently, processing is done by specialists through the use of commercial and research software packages such as numerical inverse and forward models, statistical data analysis software and visualization and data presentation packages. Information is presented to stakeholders as tables, images and reports. Processing steps, data and assumptions used for information generation are mostly opaque to endusers. As data migrates between applications the steps taken in each application (e.g. in data reduction)are often only partly documented, resulting in irreproducible results. In this approach, interactive tuning of data processing in a systematic way (e.g. changing model parameters, visualization parameters or data used) or using data processing as a discovery tool is de facto impossible. We implemented a web accessible scientific workflow system for subsurface performance monitoring. This system integrates distributed, automated data acquisition from autonomous sensor networks with server side data management and information visualization through flexible browser based data access tools. Webservices are used for communication with the sensor networks and interaction with applications. This system was originally developed for a monitoring network at the Gilt Edge Mine Superfund site, but has now been implemented for a range of different sensor networks of different complexity. The workflow framework allows for rapid and easy integration in a modular, transparent and reproducible manner of a multitude of existing applications for data analysis and processes. By embedding applications in webservice

  16. Assessment of drainage nitrogen losses on a yield-scaled basis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface nitrogen (N) losses represent a major environmental concern in agriculture, particularly from fields containing artificial drainage to prevent saturated soil conditions and increase crop production. To develop sustainable intensification strategies and achieve high yields with minimal en...

  17. Stormwater Drainage Wells

    EPA Pesticide Factsheets

    Provides information for identifying stormwater drainage wells, learn how to comply with regulations for storm water drainage wells, and how to reduce the threat to ground water from stormwater injection wells.

  18. Urine drainage bags

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000142.htm Urine drainage bags To use the sharing features on this page, please enable JavaScript. Urine drainage bags collect urine. Your bag will attach ...

  19. Submental Perforator Flap Design with a Near-Infrared Fluorescence Imaging System: The Relation between Number of Perforators, Flap Perfusion, and Venous Drainage

    PubMed Central

    Matsui, Aya; Lee, Bernard T.; Winer, Joshua H.; Laurence, Rita G.; Frangioni, John V.

    2009-01-01

    Background The submental flap is a reliable alternative to microsurgical reconstruction of facial deformities, providing an excellent cosmetic match with the contour and color of the face. In this study, we evaluated submental flap design by employing near-infrared (NIR) fluorescence angiography to identify perforator arteries (PAs). The impact of the number of preserved PAs on flap perfusion and venous drainage were quantified. Methods Indocyanine green was injected intravenously into n = 18 pigs. Three groups of 6 animals each had one, two, or three PAs preserved. The FLARE™ NIR fluorescence imaging system was employed for image acquisition. Images were recorded before and after flap creation, and every h, for 6 h. The time to maximum perfusion, the drainage ratio (an indicator of venous drainage), and the percentage of perfused flap area were analyzed statistically at each time point. Results Flaps with a single dominant PA had an initial mean perfused area of 80%, which improved to 97% at 6 h. For flaps with two and three preserved PAs, perfused area at 6 h was 99.8% and 100%, respectively. A significant increase was observed in all three metrics as more vessels were preserved. Regardless of the number of PAs preserved, though, all three metrics improved over 6 h. Conclusions NIR fluorescence angiography can reliably identify submental PAs for flap design, and can be used to assess flap perfusion and venous drainage in real-time. Flap metrics at 6 h were equivalent when either one, or multiple PAs, were preserved. PMID:19935293

  20. Use Of The Gpr To Characterize Sedimentary Structures Of Lakes In Sub-Humid Drainage System, Southeast Brazil

    NASA Astrophysics Data System (ADS)

    Aranha, P. A.; Augustin, C. H.

    2012-12-01

    PAULO ROBERTO ANTUNES ARANHA IGC - UNIVERSIDADE FEDERAL DE MINAS GERAIS - AV ANTONIO CARLOS 6.627 - CEP: 31270901-BELO HORIZONTE- MG - BRAZIL CRISTINA ROCHA AUGUSTIN - IGC - UNIVERSIDADE FEDERAL DE MINAS GERAIS - AV ANTONIO CARLOS 6.627 - CEP: 31270901-BELO HORIZONTE- MG - BRAZIL System of lakes located in the sandstones domains of Supergrupo Urucuia, in the State Park Veredas do Peruaçu, north of the State of Minas Gerais, Brazil, are common features in ecosystems of the Veredas, a biome of the Cerrado (Savanna-Open pasture). The linearity of these lakes suggests that they could have, in the past, belonged to the same drainage system, that would have been disconnected throughout the evolution of the Vereda system. The objective of this research is with the help of the GPR and using 100 MHz antennaes to obtain radargram images that could assist in the interpretation of the structures occurring at the bottom of these lakes. It is possible do identify on the radargrams reflectors that can be correlated with depositional system. These reflectore have the concave form. The results of these radargrames indicate great conformity between the concave form of the sediments and that of the bottom of the lake, allowing to assume that this deposition has been occurring since a long time ago. Therefore, if there was a connection between the study lake and those located in its proximity it has occurred a long time, before the deposition of the sedimentary sequences had been deposited. The thickness of the sediments, that varies since 2m until 5m, indicates that or either this deposition was either a very rapid one so that could generate a fast deposition, or it has been taking place during a considerable geologic long time.; Data acquisitiont;

  1. Environmental assessment and management of metal-rich wastes generated in acid mine drainage passive remediation systems.

    PubMed

    Macías, Francisco; Caraballo, Manuel A; Nieto, José Miguel

    2012-08-30

    As acid mine drainage (AMD) remediation is increasingly faced by governments and mining industries worldwide, the generation of metal-rich solid residues from the treatments plants is concomitantly raising. A proper environmental management of these metal-rich wastes requires a detailed characterization of the metal mobility as well as an assessment of this new residues stability. The European standard leaching test EN 12457-2, the US EPA TCLP test and the BCR sequential extraction procedure were selected to address the environmental assessment of dispersed alkaline substrate (DAS) residues generated in AMD passive treatment systems. Significant discrepancies were observed in the hazardousness classification of the residues according to the TCLP or EN 12457-2 test. Furthermore, the absence of some important metals (like Fe or Al) in the regulatory limits employed in both leaching tests severely restricts their applicability for metal-rich wastes. The results obtained in the BCR sequential extraction suggest an important influence of the landfill environmental conditions on the metals released from the wastes. To ensure a complete stability of the pollutants in the studied DAS-wastes the contact with water or any other leaching solutions must be avoided and a dry environment needs to be provided in the landfill disposal selected.

  2. Transient drainage summary report

    SciTech Connect

    1996-09-01

    This report summarizes the history of transient drainage issues on the Uranium Mill Tailings Remedial Action (UMTRA) Project. It defines and describes the UMTRA Project disposal cell transient drainage process and chronicles UMTRA Project treatment of the transient drainage phenomenon. Section 4.0 includes a conceptual cross section of each UMTRA Project disposal site and summarizes design and construction information, the ground water protection strategy, and the potential for transient drainage.

  3. Applications of subsurface microscopy.

    PubMed

    Tetard, Laurene; Passian, Ali; Farahi, Rubye H; Voy, Brynn H; Thundat, Thomas

    2012-01-01

    Exploring the interior of a cell is of tremendous importance in order to assess the effects of nanomaterials on biological systems. Outside of a controlled laboratory environment, nanomaterials will most likely not be conveniently labeled or tagged so that their translocation within a biological system cannot be easily identified and quantified. Ideally, the characterization of nanomaterials within a cell requires a nondestructive, label-free, and subsurface approach. Subsurface nanoscale imaging represents a real challenge for instrumentation. Indeed the tools available for high resolution characterization, including optical, electron or scanning probe microscopies, mainly provide topography images or require taggants that fluoresce. Although the intercellular environment holds a great deal of information, subsurface visualization remains a poorly explored area. Recently, it was discovered that by mechanically perturbing a sample, it was possible to observe its response in time with nanoscale resolution by probing the surface with a micro-resonator such as a microcantilever probe. Microcantilevers are used as the force-sensing probes in atomic force microscopy (AFM), where the nanometer-scale probe tip on the microcantilever interacts with the sample in a highly controlled manner to produce high-resolution raster-scanned information of the sample surface. Taking advantage of the existing capabilities of AFM, we present a novel technique, mode synthesizing atomic force microscopy (MSAFM), which has the ability to probe subsurface structures such as non-labeled nanoparticles embedded in a cell. In MSAFM mechanical actuators (PZTs) excite the probe and the sample at different frequencies as depicted in the first figure of this chapter. The nonlinear nature of the tip-sample interaction, at the point of contact of the probe and the surface of the sample, in the contact mode AFM configuration permits the mixing of the elastic waves. The new dynamic system comprises new

  4. Olfactory route for cerebrospinal fluid drainage into the cervical lymphatic system in a rabbit experimental model☆

    PubMed Central

    Liu, Haisheng; Ni, Zhili; Chen, Yetao; Wang, Dong; Qi, Yan; Zhang, Qiuhang; Wang, Shijie

    2012-01-01

    The present study analyzed the anatomical association between intracranial subarachnoid space and the cervical lymphatic system. X-ray contrast medium and Microfil® (Microfil compounds fill and opacify microvascular and other spaces of non-surviving animals and post-mortem tissue under physiological injection pressure) were injected into the cisterna magna of the rabbit, and perineural routes of cerebrospinal fluid outflow into the lymphatic system were visualized. Under a surgical operating microscope, Microfil was found within the subarachnoid space and along the olfactory nerves. At the nasal mucosa, a lymphatic network was identified near the olfactory nerves, which crossed the nasopharyngeal region and finally emptied into the superficial and deep cervical lymph nodes. Under a light microscope, Microfil was visible around the olfactory nerves and within lymphatic vessels. These results suggested that cerebrospinal fluid drained from the subarachnoid space along the olfactory nerves to nasal lymphatic vessels, which in turn, emptied into the cervical lymph nodes. This anatomical route, therefore, allowed connection between the central nervous system and the lymphatic system. PMID:25737700

  5. Comparison of analogous terrestrial and Martian drainage systems: a remote sensing based study

    NASA Astrophysics Data System (ADS)

    Vaishali, R.; Sujita, G.; Sanjeevi, S.

    2014-11-01

    With more and more missions being launched to explore the Mars, the fact that water must have once flown it is no more a mere speculation. Keeping this is mind, this paper attempts to interpret Martian and terrestrial images and provides an insight into the conditions that must have prevailed on Mars when water flowed on it. This is achieved by comparing regions selected on Mars that have evidences of a fluvial past, with regions of the Earth having similar geologic, geomorphic and physiographic characteristics. The Martian images and DEM were obtained from HiRISE onboard MRO of NASA. For the terrestrial regions, LandSat 8 (OLI) images and SRTM DEMs were used. This study has brought out many similarities in the fluvial geomorphic regime of the two planets. The presence of lobate structures, mouth bars and bifurcated channels in the Eberswalde Delta system on Mars is an indication of the interaction of the fluvial system with a large standing body of water, similar to the Mississippi Delta system on Earth. Also, the presence of braided pattern, streamlined bars and palaeochannels observed in the channels to the south of Ascraeus Mons on Mars indicates a prominent flow of water through time, similar to the Yellowstone River system present on Earth. This study thus aids in better understanding of the Martian fluvial processes and landforms.

  6. Aquifer-System Characterization by Integrating Data from the Subsurface and from Space, San Joaquin Valley, California, USA

    NASA Astrophysics Data System (ADS)

    Sneed, M.; Brandt, J. T.

    2014-12-01

    Extensive groundwater pumping from the aquifer system in the San Joaquin Valley, California, between 1926 and 1970 caused widespread aquifer-system compaction and resultant land subsidence that locally exceeded 8 m. The importation of surface water in the early 1970s resulted in decreased pumping, recovery of water levels, and a reduced rate of subsidence in some areas. Recently, land-use changes and reductions in surface-water availability have caused pumping to increase, water levels to decline, and subsidence to recur. Reduced freeboard and flow capacity of several Federal, State, and local canals have resulted from this subsidence. Vertical land-surface changes during 2005-14 in the San Joaquin Valley were determined by using space-based [Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS)] and subsurface (extensometer) data; groundwater-level and lithologic data were used to understand and estimate properties that partly control the stress/strain response of the aquifer system. Results of the InSAR analysis indicate that two areas covering about 7,200 km2 subsided 20-540 mm during 2008-10; GPS data indicate that these rates continued through 2014. Groundwater levels (stress) and vertical land-surface changes (strain) were used to estimate preconsolidation head and aquifer system storage coefficients. Integrating lithology into the analysis indicates that in some parts of the valley, the compaction occurred primarily within quickly-equilibrating fine-grained deposits in deeper parts of the aquifer system. In other parts of the valley, anomalously fine-grained alluvial-fan deposits underlie one of the most rapidly subsiding areas, indicating the shallow sediments may also contribute to total subsidence. This information helps improve hydrologic and aquifer-system compaction models, which in turn can be used to consider land subsidence as a constraint in evaluating water-resource management options.

  7. Practical application of drainage system control by using MPC in Noorderzijlvest

    NASA Astrophysics Data System (ADS)

    van Heeringen, Klaas-Jan; Gooijer, Jan; Schwanenberg, Dirk

    2013-04-01

    We discuss the implementation of a Model Predictive Control (MPC) approach for the control of the pump stations and tidal spilling sluices in the district of the regional water authority Noorderzijlvest in the north of the Netherlands. The RTC component is integrated in a Delft-FEWS application that connects to the SCADA system of the waterboard and also 17 aggregated structures including 127 individual pumps and gates The approach consists of a Nonlinear MPC in combination with a low-pass filter for state updating. The MPC runs hourly for a 5-day forecast horizon. One main objective of the control is flood mitigation during extreme taken into account by anticipating approaching rainfall events by flow forecasting. Another objective has is the reduction of pumping costs by taking advantage of gravity flow through gates during low tide conditions and the exploitation of cheaper electricity at night, both in combination with tactical usage of the available storage in the water system. Firstly the approach is tested in a closed-loop setting in combination with a detailed one-dimensional hydraulic model as the real-world replacement. A performance comparison of the approach against the existing feedback control shows pumping cost reductions in the range of 7-35% for different sub-systems or total annual cost savings in the order of 150-200 thousand Euros as well as significantly reduced peak water levels during flood events.

  8. Viral Predation and Host Immunity Structure Microbial Communities in a Terrestrial Deep Subsurface, Hydraulically Fractured Shale System

    NASA Astrophysics Data System (ADS)

    Daly, R. A.; Mouser, P. J.; Trexler, R.; Wrighton, K. C.

    2014-12-01

    Despite a growing appreciation for the ecological role of viruses in marine and gut systems, little is known about their role in the terrestrial deep (> 2000 m) subsurface. We used assembly-based metagenomics to examine the viral component in fluids from hydraulically fractured Marcellus shale gas wells. Here we reconstructed microbial and viral genomes from samples collected 7, 82, and 328 days post fracturing. Viruses accounted for 4.14%, 0.92% and 0.59% of the sample reads that mapped to the assembly. We identified 6 complete, circularized viral genomes and an additional 92 viral contigs > 5 kb with a maximum contig size of 73.6 kb. A BLAST comparison to NCBI viral genomes revealed that 85% of viral contigs had significant hits to the viral order Caudovirales, with 43% of sequences belonging to the family Siphoviridae, 38% to Myoviridae, and 12% to Podoviridae. Enrichment of Caudovirales viruses was supported by a large number of predicted proteins characteristic of tailed viruses including terminases (TerL), tape measure, tail formation, and baseplate related proteins. The viral contigs included evidence of lytic and temperate lifestyles, with the 7 day sample having the greatest number of detected lytic viruses. Notably in this sample, the most abundant virus was lytic and its inferred host, a member of the Vibrionaceae, was not detected at later time points. Analyses of CRISPR sequences (a viral and foreign DNA immune system in bacteria and archaea), linked 18 viral contigs to hosts. CRISPR linkages increased through time and all bacterial and archaeal genomes recovered in the final time point had genes for CRISPR-mediated viral defense. The majority of CRISPR sequences linked phage genomes to several Halanaerobium strains, which are the dominant and persisting members of the community inferred to be responsible for carbon and sulfur cycling in these shales. Network analysis revealed that several viruses were present in the 82 and 328 day samples; this viral

  9. Laboratory Feasibility Evaluation of a New Modified Iron Product for Use as a Filter Material to Treat Agricultural Drainage Waters

    NASA Astrophysics Data System (ADS)

    Allred, B. J.

    2010-12-01

    The removal of excess soil water with a subsurface drainage pipe system is a common agricultural practice employed to improve crop yields, especially in the Midwest U.S. However, fertilizer nutrients (nitrate and phosphate) and pesticides applied on farm fields will frequently leach downwards through the soil profile to be intercepted by the buried drainage pipes and then discharged with drainage water into neighboring streams and lakes, oftentimes producing adverse environmental impacts on local, regional, and national scales. On-site drainage water filter treatment systems can potentially be employed to prevent the release of agricultural nutrients/pesticides into adjacent waterways. A recently developed modified iron product may have promise as a filter material used within this type of drainage water treatment system. Therefore, a laboratory study was initiated to directly evaluate the feasibility of employing this new modified iron product as a filter material to treat drainage waters. Laboratory research included saturated falling-head hydraulic conductivity tests, contaminant (nutrient/pesticide) removal batch tests, and saturated solute transport column experiments. The saturated falling-head hydraulic conductivity tests indicate that the unaltered modified iron product by itself has a high enough hydraulic conductivity (> 1.0 x 10-3 cm/s) to normally allow sufficient water flow rates that are needed to make this material hydraulically practical for use in drainage water filter treatment systems. Modified iron hydraulic conductivity can be improved substantially (> 1 x 10-2 cm/s) by using only the portion of this material that is retained on a 100 mesh sieve (particle size > 0.15 mm). Batch test results carried out with spiked drainage water and either unaltered or 100 mesh sieved modified iron showed nitrate reductions of greater than 30% and 100% removal of the pesticide, atrazine. Saturated solute transport columns tests with spiked drainage water

  10. Treatment of Acid Mine Drainage By A Semipassive Barrier System, The Kristineberg Mine Site, Northern Sweden.

    NASA Astrophysics Data System (ADS)

    Morales, T. A.; Herbert, R.; Hallberg, R.

    The production of acidic mine waters containing high concentrations of sulphate and metals are of great environmental concern. One method for removing metals from leachate waters is by stimulating sulphate reduction in a treatment system, thereby producing alkalinity and hydrogen sulphide. Dissolved metals and hydrogen sulphide may then precipitate as metal sulphides. Laboratory and field studies have been con- ducted for the evaluation of the removal processes in a groundwater treatment system, in which both inorganic and organic materials have been used to neutralize acidity and to promote the growth of sulphate reducing bacteria (SRB). Dissolution of olivine and dolomite was found to be successful in neutralizing acidity, since a continuous pH buffering was obtained from pH 2-3 to pH 5-6. Column studies with olivine indi- cate higher dissolution rates obtained with higher flow rates, where Mg is released at a higher rate than Si. The rate of dolomite dissolution also shows a correlation with acid- ity flux at lower fluxes. At higher acidity fluxes, the Ca release rate appears to reach a constant level, suggesting that there are factors limiting the removal of Ca from the dolomite surface. Electron microscopy studies suggest that gypsum has formed in the columns. Field sampling during two years and laboratory results indicate that at most a limited development of sulphate reducing bacteria is obtained in the organic leaf com- post. The SRB are probably present at near neutral pH that is measured in the system, but they are not very active. One main reason for this may be the complexity of the organic substrate used. In the column studies using unamended compost, sulphate and iron removal is obtained in the organic matter at a range of flow rates, initially due to adsorption and precipitation. After the addition of an easily degradable organic carbon source, a full development of SRB was obtained with an effective removal of both iron and sulphate. Iron sulphide

  11. Integrated system for investigating sub-surface features of a rock formation

    DOEpatents

    Vu, Cung Khac; Skelt, Christopher; Nihei, Kurt; Johnson, Paul A.; Guyer, Robert; Ten Cate, James A.; Le Bas, Pierre -Yves; Larmat, Carene S.

    2015-08-18

    A system for investigating non-linear properties of a rock formation around a borehole is provided. The system includes a first sub-system configured to perform data acquisition, control and recording of data; a second subsystem in communication with the first sub-system and configured to perform non-linearity and velocity preliminary imaging; a third subsystem in communication with the first subsystem and configured to emit controlled acoustic broadcasts and receive acoustic energy; a fourth subsystem in communication with the first subsystem and the third subsystem and configured to generate a source signal directed towards the rock formation; and a fifth subsystem in communication with the third subsystem and the fourth subsystem and configured to perform detection of signals representative of the non-linear properties of the rock formation.

  12. Subsurface Remediation: Improving Long-Term Monitoring and Remedial Systems Performance Conference Proceedings

    EPA Pesticide Factsheets

    This document summarizes the presentations and workshops of a conference on improving long-term monitoring (LTM) and remedial systems performance that was held in St. Louis, Missouri between June 8th to 11th, 1999.

  13. Treatment of heavy metals by iron oxide coated and natural gravel media in Sustainable urban Drainage Systems.

    PubMed

    Norris, M J; Pulford, I D; Haynes, H; Dorea, C C; Phoenix, V R

    2013-01-01

    Sustainable urban Drainage Systems (SuDS) filter drains are simple, low-cost systems utilized as a first defence to treat road runoff by employing biogeochemical processes to reduce pollutants. However, the mechanisms involved in pollution attenuation are poorly understood. This work aims to develop a better understanding of these mechanisms to facilitate improved SuDS design. Since heavy metals are a large fraction of pollution in road runoff, this study aimed to enhance heavy metal removal of filter drain gravel with an iron oxide mineral amendment to increase surface area for heavy metal scavenging. Experiments showed that amendment-coated and uncoated (control) gravel removed similar quantities of heavy metals. Moreover, when normalized to surface area, iron oxide coated gravels (IOCGs) showed poorer metal removal capacities than uncoated gravel. Inspection of the uncoated microgabbro gravel indicated that clay particulates on the surface (a natural product of weathering of this material) augmented heavy metal removal, generating metal sequestration capacities that were competitive compared with IOCGs. Furthermore, when the weathered surface was scrubbed and removed, metal removal capacities were reduced by 20%. When compared with other lithologies, adsorption of heavy metals by microgabbro was 10-70% higher, indicating that both the lithology of the gravel, and the presence of a weathered surface, considerably influence its ability to immobilize heavy metals. These results contradict previous assumptions which suggest that gravel lithology is not a significant factor in SuDS design. Based upon these results, weathered microgabbro is suggested to be an ideal lithology for use in SuDS.

  14. Projecting the impact of climate change on the effectiveness of Controlled Drainage in the U.S. Corn Belt

    NASA Astrophysics Data System (ADS)

    Lee, C.; Bowling, L. C.; Cherkauer, K. A.

    2015-12-01

    Subsurface tile drainage systems are used to create arable conditions for agriculture in low-gradient regions with poorly drained soils, such as the U.S. Corn Belt. Traditionally these systems allow excess water to continually drain from the landscape until the water table underlying the field drops below the depth of the tile drain. These 'free draining' systems increase the volume of subsurface water, and thus increase the amount of nutrients, leaving fields. Controlled Drainage (CD) is a water conservation practice that allows farmers to decrease the volume of water leaving their field by using a control structure to manually raise the resting water table above the tile drains. In order to better understand the potential impacts of climate change on agricultural drainage in the Corn Belt, this study focuses on evaluating differences in the simulated effectiveness of CD under different climate change scenarios. The Variable Infiltration Capacity (VIC) macroscale hydrology model, with a subsurface drainage algorithm, was calibrated to nine sites across the Midwest with drainflow records from 1987 to 2012. It is used to simulate drainflow from 1980-2010 and 2035-2064 using projections for the A1B, A2 and B1 emissions scenarios from the GFDL, PCM and HadCM3 models to represent variation in the severity of projected climate change. Simulated drainflow volume, timing, and variability for both freely-drained and controlled scenarios is used to quantify projected changes in drainflow and calculate metrics of CD effectiveness in mitigating negative water quality impacts, spatially under different climate scenarios. Assessing potential changes in effectiveness of CD due to climate change is necessary to investigate potential long-term benefits and drawbacks of this best management practice.

  15. Clinical application of three-dimensional printing to the management of complex univentricular hearts with abnormal systemic or pulmonary venous drainage.

    PubMed

    McGovern, Eimear; Kelleher, Eoin; Snow, Aisling; Walsh, Kevin; Gadallah, Bassem; Kutty, Shelby; Redmond, John M; McMahon, Colin J

    2017-02-06

    In recent years, three-dimensional printing has demonstrated reliable reproducibility of several organs including hearts with complex congenital cardiac anomalies. This represents the next step in advanced image processing and can be used to plan surgical repair. In this study, we describe three children with complex univentricular hearts and abnormal systemic or pulmonary venous drainage, in whom three-dimensional printed models based on CT data assisted with preoperative planning. For two children, after group discussion and examination of the models, a decision was made not to proceed with surgery. We extend the current clinical experience with three-dimensional printed modelling and discuss the benefits of such models in the setting of managing complex surgical problems in children with univentricular circulation and abnormal systemic or pulmonary venous drainage.

  16. The use of a portable digital thoracic suction Thopaz drainage system for the management of a persistent spontaneous secondary pneumothorax in a patient with underlying interstitial lung disease.

    PubMed

    Jenkins, William S A; Hall, David P; Dhaliwal, Kev; Hill, Adam T; Hirani, Nik

    2012-06-08

    We present the case of a 68-year-old woman who presented in extremis with a secondary pneumothorax with a past history of severe idiopathic pulmonary fibrosis. Following insertion of a 32F intercostal drain, she developed a persistent broncho-pleural fistula and became dependent on negative-pressure wall-mounted suction to prevent respiratory compromise. She declined definitive surgical intervention and was therefore managed conservatively. After adhering to the wall-mounted suction method for 49 days, we obtained for use a portable digital thoracic drainage system previously used only in the cardiothoracic postoperative patient. This electronically delivered, negative-pressure drainage system induced radiographic improvement within 24 h, and allowed the patient to mobilise for the first time since admission. The patient was discharged home with the Thopaz drain in situ 8 weeks after placing it, and the drain was removed successfully with a resolved pneumothorax 20 weeks after her initial presentation.

  17. Profiling Microbial Communities in Manganese Remediation Systems Treating Coal Mine Drainage

    PubMed Central

    Hansel, Colleen M.; Burgos, William D.

    2015-01-01

    Water discharging from abandoned coal mines can contain extremely high manganese levels. Removing this metal is an ongoing challenge. Passive Mn(II) removal beds (MRBs) contain microorganisms that oxidize soluble Mn(II) to insoluble Mn(III/IV) minerals, but system performance is unpredictable. Using amplicon pyrosequencing, we profiled the bacterial, fungal, algal, and archaeal communities in four MRBs, performing at different levels, in Pennsylvania to determine whether they differed among MRBs and from surrounding soil and to establish the relative abundance of known Mn(II) oxidizers. Archaea were not detected; PCRs with archaeal primers returned only nontarget bacterial sequences. Fungal taxonomic profiles differed starkly between sites that remove the majority of influent Mn and those that do not, with the former being dominated by Ascomycota (mostly Dothideomycetes) and the latter by Basidiomycota (almost entirely Agaricomycetes). Taxonomic profiles for the other groups did not differ significantly between MRBs, but operational taxonomic unit-based analyses showed significant clustering by MRB with all three groups (P < 0.05). Soil samples clustered separately from MRBs in all groups except fungi, whose soil samples clustered loosely with their respective MRB. Known Mn(II) oxidizers accounted for a minor proportion of bacterial sequences (up to 0.20%) but a greater proportion of fungal sequences (up to 14.78%). MRB communities are more diverse than previously thought, and more organisms may be capable of Mn(II) oxidation than are currently known. PMID:25595765

  18. Evidence of traffic-related pollutant control in soil-based sustainable urban drainage systems (SUDS).

    PubMed

    Napier, F; Jefferies, C; Heal, K V; Fogg, P; Arcy, B J D; Clarke, R

    2009-01-01

    SUDS are being increasingly employed to control highway runoff and have the potential to protect groundwater and surface water quality by minimising the risks of both point and diffuse sources of pollution. While these systems are effective at retaining polluted solids by filtration and sedimentation processes, less is known of the detail of pollutant behaviour within SUDS structures. This paper reports on investigations carried out as part of a co-ordinated programme of controlled studies and field measurements at soft-engineered SUDS undertaken in the UK, observing the accumulation and behaviour of traffic-related heavy metals, oil and PAHs. The field data presented were collected from two extended detention basins serving the M74 motorway in the south-west of Scotland. Additional data were supplied from an experimental lysimeter soil core leaching study. Results show that basin design influences pollutant accumulation and behaviour in the basins. Management and/or control strategies are discussed for reducing the impact of traffic-related pollutants on the aqueous environment.

  19. The influence of precipitation intensity growth on the urban drainage systems designing

    NASA Astrophysics Data System (ADS)

    Kaźmierczak, Bartosz; Kotowski, Andrzej

    2014-10-01

    For 50 years of long observation period (1960-2009), on a high level of statistical significance (95 %), a decreasing trend of annual precipitation amounts and an increasing trend of the number of rainy days during the year (64 %) were found. For the seasonal changes (V-X), similarly, there was found a statistically significant (94 %) decreasing precipitation amount trend and an increasing trend of the number of rainy days (50 %). As far as the intensity of maximum precipitation is concerned, a very statistically significant increasing trend (95 %) was found. Taking as the basis, the model for a trend, defined for the period of 1960-2009, the increase of weighted average interval values of maximum precipitation amounts ( h ≥ 0.75 t 0.5) in the year 2059 was estimated to be about 26 %, in comparison with the starting year 1960. An increasing trend of maximum precipitation frequency in Wrocław was also proved. To a safe sewerage systems designing in Wrocław according to current standards (EN 752 2008; DWA-A118 2006), the precipitation frequency to the simulations of excessive accumulation occurrences to the land level should be changed.

  20. Evaluation of a limestone channel and wetland system for treating acid mine drainage

    SciTech Connect

    Brenner, F.J.; Pruent, P.

    1999-07-01

    The Carpentertown Coal and Coke Company operated two drift mines on the site for 17 years closing in December 1987, but the company continued to operate a cleaning plant and coal refuse disposal site until the company declared bankruptcy in June 1989. In summer of 1993, eight acid seeps developed from the 2 ha coal refuse site with a combined flow of 36 1/min with iron and manganese loading rates of 419 and 576 gm/day. In 1995, a 212 m (700 ft) open limestone channel (OLC) and a 344 m{sup 2} (1,142 ft{sup 2}) and a 2,110 m{sup 2}(43,750 ft{sup 2}) aerobic wetland was constructed as a passive treatment system. over the 34-month monitoring period, the acid loading to the receiving stream was reduced by 88% with a corresponding increase of 111% in alkalinity. The iron and manganese loading to the receiving stream was reduced by 91% and 57%, respectively.

  1. Profiling microbial communities in manganese remediation systems treating coal mine drainage.

    PubMed

    Chaput, Dominique L; Hansel, Colleen M; Burgos, William D; Santelli, Cara M

    2015-03-01

    Water discharging from abandoned coal mines can contain extremely high manganese levels. Removing this metal is an ongoing challenge. Passive Mn(II) removal beds (MRBs) contain microorganisms that oxidize soluble Mn(II) to insoluble Mn(III/IV) minerals, but system performance is unpredictable. Using amplicon pyrosequencing, we profiled the bacterial, fungal, algal, and archaeal communities in four MRBs, performing at different levels, in Pennsylvania to determine whether they differed among MRBs and from surrounding soil and to establish the relative abundance of known Mn(II) oxidizers. Archaea were not detected; PCRs with archaeal primers returned only nontarget bacterial sequences. Fungal taxonomic profiles differed starkly between sites that remove the majority of influent Mn and those that do not, with the former being dominated by Ascomycota (mostly Dothideomycetes) and the latter by Basidiomycota (almost entirely Agaricomycetes). Taxonomic profiles for the other groups did not differ significantly between MRBs, but operational taxonomic unit-based analyses showed significant clustering by MRB with all three groups (P < 0.05). Soil samples clustered separately from MRBs in all groups except fungi, whose soil samples clustered loosely with their respective MRB. Known Mn(II) oxidizers accounted for a minor proportion of bacterial sequences (up to 0.20%) but a greater proportion of fungal sequences (up to 14.78%). MRB communities are more diverse than previously thought, and more organisms may be capable of Mn(II) oxidation than are currently known.

  2. Field-scale modeling of subsurface tile-drained soils using an equivalent-medium approach

    NASA Astrophysics Data System (ADS)

    Carlier, Jean Philippe; Kao, Cyril; Ginzburg, Irina

    2007-07-01

    SummaryResearch conducted for the last 35 years has shown that subsurface drainage has a significant impact on hydrology and contaminant transport. This can be observed at the field-scale and also at the watershed scale. Impacts are always associated with modifying otherwise natural flow paths. Most computer model representations of drainage have been drawn at the field-scale. These models require relatively precise data that are usually unavailable when simulating hydrology and water quality in large watersheds. We believe that in this case drainage representation should be simplified and yet closely match observations. As a first step towards incorporating drainage systems into large-scale hydrological models, we propose an equivalent representation of drains buried in a soil profile by using a homogeneous anisotropic porous medium without drains. This representation is based on a "self-consistent" approach and on geometrical considerations. Simplification is such that calculating the equivalent hydraulic conductivity requires only information on the main length and spacing of the tile drains and not on their precise location. This approach also provides a much simpler discretisation of the domain because of the absence of internal boundary conditions on the drainage pipes. Compared to other methods that have simplified drainage representation in existing watershed models, it requires no parameter fitting. Two alternatives to the method are presented: in the first one, the soil profile equipped with the actual drain pipes is represented by an equivalent, horizontally layered system with no pipes; in the second, the layered system has been replaced with an equivalent homogeneous profile. The efficiency of these approaches was tested against a classical representation of tile drains using the SWMS 3D code, which solves the Richards equation for a typical drained plot configuration. The equivalent-medium approach appears to give satisfying results for global water

  3. A diagnosis of sub-surface water table dynamics in low hydraulic conductivity soils in the sugar cane fields of Pongola, South Africa

    NASA Astrophysics Data System (ADS)

    Malota, Mphatso; Senzanje, Aidan

    2016-04-01

    Water and land are the two natural resources restraining crop production in South Africa. With the increasing demand for food, emphasis has shifted from the sole reliance on rain fed crop production, to irrigation. The deterioration in irrigation water quality from surface water sources is, however, posing a big challenge to the sustainability of irrigated crop production. This is because more water is required for leaching, resulting in shallow water tables in agricultural lands. The installation of well designed subsurface drainage systems alone is not enough; the provision of timely maintenance is also necessary. In this study, the extent and severity of problems as a consequence of shallow water tables and their possible causes were investigated at three sugarcane fields in Pongola, South Africa, having low hydraulic conductivity soils. Also investigated were soil salinity levels and the temporal variation in the salinity of the irrigation water. A water table map of a 32 ha sugarcane field was generated, using observed water table depth (WTD) data from 36 piezometers monitored from September 2011 to February 2012. Out of the total 32 ha under cultivation, 12% was found to be affected by shallow WTDs of less than the 1.0 m design WTD. The inability of natural drainage to cope with subsurface drainage needs and the poor maintenance of subsurface drainage systems contributed to the shallow water tables in the area. Furthermore, the currently adopted drainage design criteria also proved unsatisfactory with mean observed water table depth and drainage discharge (DD) of 20% and 50%, respectively, less than their respective design levels. The salinity of the irrigation water was, on average, 32% higher than threshold tolerance level of sugarcane. The root zone soil salinity levels at the three study sites were greater than the 1.7 dS m-1 threshold for sugar cane. The subsurface drainage design criteria adopted at the site needs to be revisited by ensuring that the

  4. Land drainage system detection using IR and visual imagery taken from autonomous mapping airship and evaluation of physical and spatial parameters of suggested method

    NASA Astrophysics Data System (ADS)

    Koska, Bronislav; Křemen, Tomáš; Štroner, Martin; Pospíšil, Jiří; Jirka, Vladimír.

    2014-10-01

    An experimental approach to the land drainage system detection and its physical and spatial parameters evaluation by the form of pilot project is presented in this paper. The novelty of the approach is partly based on using of unique unmanned aerial vehicle - airship with some specific properties. The most important parameters are carrying capacity (15 kg) and long flight time (3 hours). A special instrumentation was installed for physical characteristic testing in the locality too. The most important is 30 meter high mast with 3 meter length bracket at the top with sensors recording absolute and comparative temperature, humidity and wind speed and direction in several heights of the mast. There were also installed several measuring units recording local condition in the area. Recorded data were compared with IR images taken from airship platform. The locality is situated around village Domanín in the Czech Republic and has size about 1.8 x 1.5 km. There was build a land drainage system during the 70-ties of the last century which is made from burnt ceramic blocks placed about 70 cm below surface. The project documentation of the land drainage system exists but real state surveying haveńt been never realized. The aim of the project was land surveying of land drainage system based on infrared, visual and its combination high resolution orthophotos (10 cm for VIS and 30 cm for IR) and spatial and physical parameters evaluation of the presented procedure. The orthophoto in VIS and IR spectrum and its combination seems to be suitable for the task.

  5. Mathematical modeling of diffuse flow in seafloor hydrothermal systems: The potential extent of the subsurface biosphere at mid-ocean ridges

    NASA Astrophysics Data System (ADS)

    Lowell, R. P.; Houghton, J. L.; Farough, A.; Craft, K. L.; Larson, B. I.; Meile, C. D.

    2015-09-01

    We describe a variety of one- and two-dimensional mathematical modeling approaches to characterizing diffuse flow circulation at mid-ocean ridge hydrothermal systems. The goal is to estimate the potential extent of the sub-seafloor microbial biosphere based on subsurface contours of the 120 °C isotherm as determined from the various models. The models suggest that the sub-seafloor depth for microbial life may range from less than 1 m in some places to the thickness of crustal layer 2A of ∼ 500 m in others. This depth depends primarily on how diffuse flow is driven. The 120 °C isotherm tends to be much deeper if diffuse flow is induced as boundary layer flow near high-temperature plumes, than if it results from conductive cooling or mixing near the seafloor. Because the heat flow alone may not allow identification of the flow regime in the subsurface, we highlight the use of chemical tracers as an additional constraint that sheds light into the flow and reaction patterns associated with vents. We use thermodynamic modeling, which connects the temperature of the diffuse fluid to its chemical composition. As the temperature-composition relationships differ for mixing versus conductive heating and cooling, the fluid geochemistry can shed light on subsurface transport. Using methane as an example, the geochemical models indicate subsurface microbial methane production and consumption in different regions of the vent field near EPR 9 °50‧ N.

  6. Earthquake hypocenters and focal mechanisms in central Oklahoma reveal a complex system of reactivated subsurface strike-slip faulting

    USGS Publications Warehouse

    McNamara, Daniel E.; Benz, Harley M.; Herrmann, Robert B.; Bergman, Eric A.; Earle, Paul S.; Holland, Austin F.; Baldwin, Randy W.; Gassner, A.

    2015-01-01

    The sharp increase in seismicity over a broad region of central Oklahoma has raised concern regarding the source of the activity and its potential hazard to local communities and energy industry infrastructure. Since early 2010, numerous organizations have deployed temporary portable seismic stations in central Oklahoma in order to record the evolving seismicity. In this study, we apply a multiple-event relocation method to produce a catalog of 3,639 central Oklahoma earthquakes from late 2009 through 2014. RMT source parameters were determined for 195 of the largest and best-recorded earthquakes. Combining RMT results with relocated seismicity enabled us to determine the length, depth and style-of-faulting occurring on reactivated subsurface fault systems. Results show that the majority of earthquakes occur on near vertical, optimally oriented (NE-SW and NW-SE), strike-slip faults in the shallow crystalline basement. These are necessary first order observations required to assess the potential hazards of individual faults in Oklahoma.

  7. Earthquake hypocenters and focal mechanisms in central Oklahoma reveal a complex system of reactivated subsurface strike-slip faulting

    NASA Astrophysics Data System (ADS)

    McNamara, D. E.; Benz, H. M.; Herrmann, R. B.; Bergman, E. A.; Earle, P.; Holland, A.; Baldwin, R.; Gassner, A.

    2015-04-01

    The sharp increase in seismicity over a broad region of central Oklahoma has raised concern regarding the source of the activity and its potential hazard to local communities and energy industry infrastructure. Since early 2010, numerous organizations have deployed temporary portable seismic stations in central Oklahoma in order to record the evolving seismicity. In this study, we apply a multiple-event relocation method to produce a catalog of 3639 central Oklahoma earthquakes from late 2009 through 2014. Regional moment tensor (RMT) source parameters were determined for 195 of the largest and best recorded earthquakes. Combining RMT results with relocated seismicity enabled us to determine the length, depth, and style of faulting occurring on reactivated subsurface fault systems. Results show that the majority of earthquakes occur on near-vertical, optimally oriented (NE-SW and NW-SE), strike-slip faults in the shallow crystalline basement. These are necessary first-order observations required to assess the potential hazards of individual faults in Oklahoma.

  8. Optimizing groundwater monitoring systems for landfills with random leaks under heterogeneous subsurface conditions

    NASA Astrophysics Data System (ADS)

    Yenigül, N. B.; Elfeki, A. M. M.; van den Akker, C.; Dekking, F. M.

    2013-12-01

    Landfills are one of the most common human activities threatening the natural groundwater quality. The landfill may leak, and the corresponding plumes may contaminate an area, entailing costly remediation measures. The objective of the installation of monitoring systems at landfill sites is to detect the contaminant plumes before they reach the regulatory compliance boundary in order to enable cost-effective counter measures. In this study, a classical decision analysis approach is linked to a stochastic simulation model to determine the optimal groundwater monitoring system given uncertainties due to the hydrogeological conditions and contaminant source characteristics. A Monte Carlo approach is used to incorporate uncertainties. Hydraulic conductivity and the leak location are the random inputs of the simulation model. The design objectives are to: (1) maximize the detection probability, (2) minimize the area of contamination at the time of detection, and (3) minimize the total cost of the monitoring system. A synthetic test case based on a real-world case in the Netherlands is analyzed. The results show that monitoring systems located close to the source are optimal except for the cases with very high unit installation and sampling cost and/or very cheap unit remediation.

  9. [Eye and lymph drainage].

    PubMed

    Grüntzig, J; Schicha, H; Huth, F

    1979-06-01

    Up to now lymphatics in the eye could not be pointed out. An ocular lymph drainage is denied. Földi succeeded in producing experimentally the syndrome of "lymphostatic encephalopathy and ophthalmopathy" by operative blockade of the cervical lymphatics in animals. In the first part of the present paper a historical view considering the subject "Eye and lymphatic system" is given. In the second part it is entered into the particulars of own experimental studies. As to our own investigations, rabbits have been injected 99mTc-sulfur-colloid, 99mTc-microcolloid, 99mTc-Albumin and 198Au-colloid into the retrobulbar space, anterior chamber, vitreous body and subconjuctival space of one eye. Measurements of the activity's distribution have been made in vivo with an Anger type camera (pho-Gamma-IV Hp, Searle Nuclear Chicago) and in vitro after section with a sodium iodine crystal well counter (Clinimat-200, Picker). In some animals the investigation has been combined with a bilateral dissection of the cervical lymph nodes. After injection in the retrobulbar space a significant concentration of the activity could be observed for the most part in the equilateral Lymphonodulus cervicalis profundus. By the cervical lymph blockade the removal of lymphoctopic substances from the retrobulbar space was largely inhibited. After injection in the anterior chamber a significant concentration could be observed for the most part in the equilateral Lymphonodulus cervicalis superficialis. After intravitreal injection a drainage to the bilateral deep cervical lymph nodes could be observed. After injection into the subconjunctival space a significant accumulation of activity could be registered in the equilateral Lymphonoduli mandibulares and cervicales superficiales. The data substantiate a segmental lymph drainage from the eye: vitreous body and retrobulbar space for the most part into the Lymphonoduli cervicales profundi, anterior chamber and subconjunctival space for the most part into

  10. Wastewater drainage system as an occult reservoir in a protracted clonal outbreak due to metallo-β-lactamase-producing Klebsiella oxytoca.

    PubMed

    Vergara-López, S; Domínguez, M C; Conejo, M C; Pascual, Á; Rodríguez-Baño, J

    2013-11-01

    We describe the epidemiology of a protracted nosocomial clonal outbreak due to multidrug-resistant IMP-8 producing Klebsiella oxytoca (MDRKO) that was finally eradicated by removing an environmental reservoir. The outbreak occurred in the ICU of a Spanish hospital from March 2009 to November 2011 and evolved over four waves. Forty-two patients were affected. First basic (active surveillance, contact precautions and reinforcement of surface cleaning) and later additional control measures (nurse cohorting and establishment of a minimum patient/nurse ratio) were implemented. Screening of ICU staff was repeatedly negative. Initial environmental cultures, including dry surfaces, were also negative. The above measures temporarily controlled cross-transmission but failed to eradicate the epidemic MDRKO strain that reappeared two weeks after the last colonized patients in waves 2 and 3 had been discharged. Therefore, an occult environmental reservoir was suspected. Samples from the drainpipes and traps of a sink were positive; removal of the sink reduced the rate number but did not stop new cases that clustered in a cubicle whose horizontal drainage system was connected with the eliminated sink. The elimination of the horizontal drainage system finally eradicated the outbreak. In conclusion, damp environmental reservoirs (mainly sink drains, traps and the horizontal drainage system) could explain why standard cross-transmission control measures failed to control the outbreak; such reservoirs should be considered even when environmental cultures of surfaces are negative.

  11. Wireless Subsurface Microsensors for Health Monitoring of Thermal Protection Systems on Hypersonic Vehicles

    NASA Technical Reports Server (NTRS)

    Milos, Frank S.; Watters, David G.; Pallix, Joan B.; Bahr, Alfred J.; Huestis, David L.; Arnold, Jim (Technical Monitor)

    2001-01-01

    Health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles in order to reduce life cycle costs, to increase safety margins, and to improve mission reliability. NASA Ames is leading the effort to develop inspection and health management technologies for thermal protection systems. This paper summarizes a joint project between NASA Ames and SRI International to develop 'SensorTags,' radio frequency identification devices coupled with event-recording sensors, that can be embedded in the thermal protection system to monitor temperature or other quantities of interest. Two prototype SensorTag designs containing thermal fuses to indicate a temperature overlimit are presented and discussed.

  12. Agricultural Drainage Water Management: Potential Impact and Implementation Strategies for Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin (and the Lake Erie Basin) area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Dra...

  13. Control of impact crater fracture systems on subsurface hydrology, ground subsidence, and collapse, Mars

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Sasaki, S.; Dohm, J.M.; Tanaka, K.L.; Strom, B.; Kargel, J.; Kuzmin, R.; Miyamoto, H.; Spray, J.G.; Fairen, A.G.; Komatsu, G.; Kurita, K.; Baker, V.

    2005-01-01

    Noachian layered materials are pervasively exposed throughout the highlands of Mars. The layered deposits, in places many kilometers thick, exhibit impact craters of diverse morphologic characteristics, ranging from highly degraded to pristine, most of which formed during the period of heavy bombardment. In addition, exhumed impact craters, ancient channels, and fluvial and alluvial fans are visible in the layered deposits through MOC imagery. These features are more abundant in Noachian terrains, which indicates relatively high erosion rates during ancient Mars that competed with heavy meteoritic bombardment. The Noachian layered materials are thus expected to contain numerous buried impact craters in various states of preservation. Here, we propose that impact craters (buried and exposed) and associated fracture systems dominate the basement structural fabric of the ancient highlands and that they have significantly influenced the hydrogeology. Diversity in the occurrence of high and low densities of impact craters and associated fracture systems controls the magnitude of the local effects of magmatic-driven hydrothermal activity. In and surrounding the Tharsis region, for example, the formation of chaotic terrains (the source regions of the circum-Chryse outflow channel system) and a large diversity of collapse structures, including impact crater moats and pit chains, appear to be the result of enhanced hydrothermal activity. Copyright 2005 by the American Geophysical Union.

  14. The distribution and growth of roots for four sugarcane cultivars irrigated by a subsurface drip irrigation system

    NASA Astrophysics Data System (ADS)

    Yukitaka Pessinatti Ohashi, Augusto; Barros de Oliveira Silva, André Luiz; Célia de Matos Pires, Regina; Vasconcelos Ribeiro, Rafael

    2013-04-01

    The use of subsurface drip irrigation (SDI) in sugarcane cultivation is an interesting cultural practice to improve production and allow cultivation in marginal lands due to water deficit conditions or to reach high yield and to increase longevity of plants. The SDI allows improving the water use efficiency, due to the application of water and nutrients in the root zone plants. It is necessary knowledge of soil and plant parameters, such as root system to improve irrigation system use efficiency. However, despite of the agronomic importance, few studies of sugarcane roots have been performed. The use of root scanner is an alternative to the evaluation of the root system. The mentioned equipment enables the continuous study of the roots throughout the cycle and for many years, but data about the use of this method for sugarcane are scarce. The aim of this study was to determine the distribution and growth of roots for four sugarcane cultivars root system. The field experiment was carried out in Campinas SP Brazil, with IACSP95-5000, IACSP94-2094, IACSP94-2101 and SP79-1011 cultivars. The irrigation was performed by subsurface drip system and the soil moisture was monitored by capacitance probes. Three access tubes with 1.05 m-length were used for each cultivar. The images were caught with Root Scanner CI-600™ in two dates, 38 and 58 days after harvest (DAH) of cane-plant, in the second cycle (1st cane ratoon) in five depths and were analyzed by the software RootSnap! ™. The results show that, except for cultivar IACSP94-2094, more than 80% of root length was found in the first 0.40 m of soil profile. Until 38 DAH the root growth of cultivar IACSP94-2101 were approximately fourfold higher than other three ones in the 0 to 0.20 m layer, sevenfold higher to 0.20 to 0.40 m layer and threefold to 0.40 to 0.60 m soil profile layer. However, between 38 and 58 DAH the cultivar SP79-1011 presented higher growth taxes, being almost twofold higher than IACSP94-2101 at 0 to

  15. Heimlich valve for chest drainage.

    PubMed

    Heimlich, H J

    1983-01-01

    The Heimlich chest drainage valve was developed so that the process of draining the pleural cavity could be accomplished in a safe, relatively simple, and efficient manner. Replacing the cumbersome underwater drainage bottle system, the Heimlich valve connects to chest tubing and allows fluid and air to pass in one direction only. The valve, which functions in any position, need never be clamped, and regulated suction can be attached to it if necessary. The valve drains into a plastic bag that can be held at any level, allowing the patient undergoing chest drainage to be ambulatory simply by carrying the bag. The construction and function of the valve is easily understood by medical and nursing staffs. It is presterilized, stored in a sterile package, and readily utilized on emergency vehicles and in the operating room.

  16. Modeling coastal plain drainage ditches with SWAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the low-relief Eastern Shore region of Maryland, extensive land areas used for crop production require drainage systems either as tile drains or open ditches. The prevalence of drainage ditches in the region is being linked to increased nutrient loading of the Chesapeake Bay. Process-based water ...

  17. ADVANCES IN BIOTREATMENT OF ACID MINE DRAINAGE AND BIORECOVERY OF METALS: 2. MEMBRANE BIOREACTOR SYSTEM FOR SULFATE REDUCTION

    EPA Science Inventory

    Acid-mine drainage (AMD) is a severe pollution problem attributed to past mining activities. AMD is an acidic, metal-bearing wastewater generated by the oxidation of metal sulfides to sulfates by Thiobacillus bacteria in both the active and abandoned mining operations. The wastew...

  18. The course of chronic subdural hematomas after burr-hole craniostomy with and without closed-system drainage.

    PubMed

    Markwalder, T M

    2000-07-01

    The author provides a comprehensive review of the results of surgical treatment of chronic subdural hematomas (CSHs). The postoperative clinical course of CSH is studied with respect to the influence of neomembranous organization, cortical expansion, and subdural pressure. The importance of subdural drainage is emphasized.

  19. Wireless Subsurface Sensors for Health Monitoring of Thermal Protection Systems on Hypersonic Vehicles

    NASA Technical Reports Server (NTRS)

    Milos, Frank S.; Arnold, Jim (Technical Monitor)

    2001-01-01

    Health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles (RLVs) in order to reduce life cycle costs, to increase safety margins, and to improve mission reliability. NASA Ames is leading the effort to develop inspection and health management technologies for thermal protection systems. This paper summarizes a joint project between NASA Ames and industry partners to develop "wireless" devices that can be embedded in the thermal protection system to monitor temperature or other quantities of interest. These devices are sensors integrated with radio-frequency identification (RFID) microchips to enable non-contact communication of sensor data to an external reader that may be a hand-held scanner or a large portal. Both passive and active prototype devices have been developed. The passive device uses a thermal fuse to indicate the occurrence of excessive temperature. This device has a diameter under 0.13 cm. (suitable for placement in gaps between ceramic TPS tiles on an RLV) and can withstand 370 C for 15 minutes. The active device contains a small battery to provide power to a thermocouple for recording a temperature history during flight. The bulk of the device must be placed beneath the TPS for protection from high temperature, but the thermocouple can be placed in a hot location such as near the external surface.

  20. TITLE III EVALUATION REPORT FOR THE SURFACE AND SUBSURFACE POWER SYSTEM

    SciTech Connect

    W.J. REED

    1999-08-16

    The objective of this evaluation is to provide recommendations to ensure consistency between the technical baseline requirements, baseline design, and the alternate constructed power system. Recommendations for resolving discrepancies between the alternate constructed power system, the technical baseline requirements, and the baseline design are included in this report. Cost and schedule estimates are provided for all recommended modifications. This report does not address items which do not meet current safety or code requirements. These items are identified to the CMO and immediate action is taken to correct the situation. The report does identify safety and code items for which the A/E is recommending improvements. The recommended improvements will exceed the minimum requirements of applicable code and safety guidelines. These recommendations are intended to improve and enhance the operation and maintenance of the facility. This Title III Evaluation Report (TER) does not include evaluation of surface electrical construction support facilities used to provide temporary construction power where the intent to remove such facilities when construction is completed such as tent storage buildings, shop buildings, fuel storage area etc. Furthermore, this TER does not include the extension of the existing overhead power lines to the booster pump station that was designed, installed, and is maintained by Nevada Test Site (NTS).

  1. Nutrient export in tile drainage: Comparing manure injection to fertigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface tile drainage of agricultural land is implicated as a major source of nutrients to the Mississippi River. To protect water quality, land application of manure should maximize crop nutrient use and minimize nutrient loss. Weather constraints and regulations restrict the period during which...

  2. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  3. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  4. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  5. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  6. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  7. Modeling of pyrite oxidation in saturated and unsaturated subsurface flow systems

    SciTech Connect

    Xu, Tianfu; White, Stephen P.; Pruess, Karsten; Brimhall, George H.

    2000-02-10

    Pyrite oxidation (FeS2) causes acidification and mobilization of metals. Mathematical modeling of pyrite oxidation in variably saturated reactive flow systems is challenging because (1) it occurs through a complex interplay of multi-phase flow and transport processes, and (2) aqueous concentrations of key species vary over tens orders of magnitude in different redox conditions. Here we present a general multi-phase reactive transport model for redox processes. Two alternative implementations were made in the TOUGHREACT and TOUGH2-CHEM simulation codes which use sequential iteration and simultaneous solution, respectively. Both codes are used to simulate a fully and a variably-saturated pyrite oxidation problem with simple 1-D flow and reaction conditions. Results from both codes indicates that the effects of oxygen partial pressure reduction due to reactions on the fluid flow is not significant under ambient conditions. However, it must be noted that when fluid flow and chemical reactions are strongly coupled, such as when boiling takes place in geothermal reservoirs, this could be essential. The fully simultaneous approach has a complete process description. The sequential iteration approach is found to be more efficient computationally. The oxygen gas diffusion process plays a dominant role in the chemical evolution for pyrite oxidation in unsaturated conditions. An example in 2-D fractured rock is presented to demonstrate pyrite oxidation under complex flow and geochemical conditions. This example shows that pyrite oxidation exerts strong influence on hydrogeochemical evolution in variably saturated flow systems. The alteration of primary rock minerals and the development of secondary mineral assemblages predicted are consistent with field observations. This example serves as a prototype for oxidative weathering processes with broad significance for geoscientific, engineering, and environmental applications.

  8. Managing tile drainage, subirrigation, and nitrogen fertilization to enhance crop yields and reduce nitrate loss.

    PubMed

    Drury, C F; Tan, C S; Reynolds, W D; Welacky, T W; Oloya, T O; Gaynor, J D

    2009-01-01

    Improving field-crop use of fertilizer nitrogen is essential for protecting water quality and increasing crop yields. The objective of this study was to determine the effectiveness of controlled tile drainage (CD) and controlled tile drainage with subsurface irrigation (CDS) for mitigating off-field nitrate losses and enhancing crop yields. The CD and CDS systems were compared on a clay loam soil to traditional unrestricted tile drainage (UTD) under a corn (Zea Mays L.)-soybean (Glycine Max. (L.) Merr.) rotation at two nitrogen (N) fertilization rates (N1: 150 kg N ha(-1) applied to corn, no N applied to soybean; N2: 200 kg N ha(-1) applied to corn, 50 kg N ha(-1) applied to soybean). The N concentrations in tile flow events with the UTD treatment exceeded the provisional long-term aquatic life limit (LT-ALL) for freshwater (4.7 mg N L(-1)) 72% of the time at the N1 rate and 78% at the N2 rate, whereas only 24% of tile flow events at N1 and 40% at N2 exceeded the LT-ALL for the CDS treatment. Exceedances in N concentration for surface runoff and tile drainage were greater during the growing season than the non-growing season. At the N1 rate, CD and CDS reduced average annual N losses via tile drainage by 44 and 66%, respectively, relative to UTD. At the N2 rate, the average annual decreases in N loss were 31 and 68%, respectively. Crop yields from CDS were increased by an average of 2.8% relative to UTD at the N2 rate but were reduced by an average of 6.5% at the N1 rate. Hence, CD and CDS were effective for reducing average nitrate losses in tile drainage, but CDS increased average crop yields only when additional N fertilizer was applied.

  9. An integrated, subsurface characterization system for real-time, in-situ field analysis

    SciTech Connect

    Baumgart, C.W.; Creager, J.; Mathes, J.; Pounds, T.; VanDeusen, A.; Warthen, B.

    1996-02-01

    This paper describes current efforts at AlliedSignal Federal Manufacturing and Technologies (FM and T) to develop and field an in-situ, data analysis platform to acquire, process, and display site survey data in near real-time. In past years, FM and T has performed a number of site survey tasks. Each of these surveys was unique in application as well as in the type of data processing and analysis that was required to extract and visualize useful site characterization information. However, common to each of these surveys were the following specific computational and operational requirements: (1) a capability to acquire, process, and visualize the site survey data in the field; (2) a capability to perform all processing in a timely fashion (ideally real-time); and (3) a technique for correlating (or fusing) data streams from multiple sensors. Two more general, but no less important, requirements include system architecture modularity and positioning capability. Potential applications include: survey, evaluation, and remediation of numerous Department of Defense and Department of Energy waste sites; real-time detection and characterization of unexploded ordnance and landmines; survey, evaluation, and remediation of industrial waste sites; location of underground utility lines; and providing law enforcement agencies with real-time surveys of crime scenes. The paper describes an integrated data acquisition, processing, and visualization platform that is capable of performing in-situ data processing, interpretation, and visualization in real-time.

  10. Preliminary subsurface hydrologic considerations: Columbia River Plateau Physiographic Province. Assessment of effectiveness of geologic isolation systems

    SciTech Connect

    Veatch, M.D.

    1980-04-01

    This report contains a discussion of the hydrologic conditions of the Columbia River Plateau physiographic province. The Columbia River Plateau is underlain by a thick basalt sequence. The Columbia River basalt sequence contains both basalt flows and sedimentary interbeds. These sedimentary interbeds, which are layers of sedimentary rock between lava flows, are the main aquifer zones in the basalt sequence. Permeable interflow zones, involving the permeable top and/or rubble bottom of a flow, are also water-transmitting zones. A number of stratigraphic units are present in the Pasco Basin, which is in the central part of the Columbia River Plateau. At a conceptual level, the stratigraphic sequence from the surface downward can be separated into four hydrostratigraphic systems. These are: (1) the unsaturated zone, (2) the unconfined aquifer, (3) the uppermost confined aquifers, and (4) the lower Yakima basalt hydrologic sequence. A conceptual layered earth model (LEM) has been developed. The LEM represents the major types of porous media (LEM units) that may be encountered at a number of places on the Columbia Plateau, and specifically in the Pasco Basin. The conceptual LEM is not representative of the actual three-dimensional hydrostratigraphic sequence and hydrologic conditions existing at any specific site within the Columbia Plateau physiographic province. However, the LEM may be useful for gaining a better understanding of how the hydrologic regime may change as a result of disruptive events that may interact with a waste repository in geologic media.

  11. The Use of Near-Surface Geophysics in the Design of a Subsurface Water Management System

    NASA Astrophysics Data System (ADS)

    Fogwell, T. W.; Rymer, M.

    2008-12-01

    The buildings on a college campus have frequently been flooded at various times of the year. The existence of several springs on the campus, including at least one immediately adjacent to one of the buildings, suggested that a high water table was the cause of some of the problems. The groundwater enters the campus from the direction of the hills east of the campus. We carried out investigations of the hydrology of the campus in order to an engineer a solution to the water intrusion problem. In the process of evaluating the hydrology, we instigated a monitoring plan, installed the necessary wells for this plan, and carried out monitoring over both wet and dry seasons. The information from this monitoring has been combined with geophysical information derived from seismic surveys, core samples, and bore hole logging in order to achieve a complete picture of the hydrology of the campus. Geophysical logs have been produced for the same wells from which we took the core samples. This information has then been combined with seismic p-wave and s-wave velocity data derived from a total of four intersecting lines on the campus in order to produce a comprehensive understanding of both the hydrology and the governing geological features. The exact location of a fault running through the campus was determined, as well as any effect that it might have on the hydrology. In the effort to save the campus buildings from flooding, a method of diverting the groundwater has been proposed. Since the campus has expressed interest in keeping the project relatively eco-friendly, the design option presented has resulted in minimum energy costs and maximum resource conservation. The overall system design consists of interception and infiltration.

  12. Remote forcing of subsurface currents and temperatures near the northern limit of the California Current System

    NASA Astrophysics Data System (ADS)

    Engida, Zelalem; Monahan, Adam; Ianson, Debby; Thomson, Richard E.

    2016-10-01

    Local and remote wind forcing of upwelling along continental shelves of coastal upwelling regions play key roles in driving biogeochemical fluxes, including vertical net fluxes of carbon and nutrients. These fluxes are responsible for high primary productivity, which in turn supports a lucrative fishery in these regions. However, the relative contributions of local versus remote wind forcing are not well quantified or understood. We present results of coherence analyses between currents at a single mooring site (48.5°N, 126°W) in the northern portion of the California Current System (CalCS) from 1989 to 2008 and coincident time series of North America Regional Reanalysis (NARR) 10 m wind stress within the CalCS (36-54°N, 120-132°W). The two-decade-long current records from the three shallowest depths (35, 100, and 175 m) show a remote response to winds from south as far as 36°N. In contrast, only temperatures at the deepest depth (400 m) show strong coherences with remote winds. Weaker local wind influence is observed in both the currents and 400 m temperatures but is mostly due to the large spatial coherence within the wind field itself. Lack of coherence between distal winds and the 400 m currents suggests that the temperature variations at that depth are driven by vertical motion resulting from poleward travelling coastal trapped waves (CTWs). Understanding the effects of remote forcing in coastal upwelling regions is necessary for determining the occurrence and timing of extreme conditions in coastal oceans, and their subsequent impact on marine ecosystems.

  13. Nonintrusive subsurface surveying capability

    SciTech Connect

    Tunnell, T.W.; Cave, S.P.

    1994-06-01

    This presentation describes the capabilities of a ground-pentrating radar (GPR) system developed by EG&G Energy Measurements (EM), a prime contractor to the Department of Energy (DOE). The focus of the presentation will be on the subsurface survey of DOE site TA-21 in Los Alamos, New Mexico. EG&G EM developed the system for the Department of Defense. The system is owned by the Department of the Army and currently resides at KO in Albuquerque. EM is pursuing efforts to transfer this technology to environmental applications such as waste-site characterization with DOE encouragement. The Army has already granted permission to use the system for the waste-site characterization activities.

  14. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system

    NASA Astrophysics Data System (ADS)

    Ohtomo, Y.; Ijiri, A.; Ikegawa, Y.; Tsutsumi, M.; Imachi, H.; Uramoto, G.; Hoshino, T.; Morono, Y.; Tanikawa, W.; Hirose, T.; Inagaki, F.

    2013-12-01

    The geological CO2 sequestration into subsurface unmineable oil/gas fields and coal formations has been considered as one of the possible ways to reduce dispersal of anthropogenic greenhouse gasses into the atmosphere. However, feasibility of CO2 injection largely depends on a variety of geological and economical settings, and its ecological consequences have remained largely unpredictable. To address these issues, we developed a new flow-through-type CO2 injection system designated as the 'geobio-reactor system' to examine possible geophysical, geochemical and microbiological impact caused by CO2 injection under in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. In this study, we investigated Eocene bituminous coal-sandstones in the northwestern Pacific coast, Hokkaido, Japan, using the geobio-reactor system. Anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 mL/min, respectively) were continuously supplemented into the coal-sand column under the pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. Molecular analysis of bacterial 16S rRNA genes showed that predominant bacterial components were physically dispersed from coal to sand as the intact form during experiment. Cultivation experiments from sub-sampling fluids indicated that some terrestrial microbes could preserve their survival in subsurface condition. Molecular analysis of archaeal 16S rRNA genes also showed that no methanogens were activated during experiment. We also anaerobically incubated the coal sample using conventional batch-type cultivation technique with a medium for methanogens. After one year of the batch incubation at 20°C, methane could be detected from the cultures except for the acetate-fed culture. The sequence of archaeal 16S rRNA genes via PCR amplification obtained from the H2 plus formate-fed culture was affiliated with a hydrogenotrophic methanogen within the genus Methanobacterium, whereas the methanol plus trimethylamine culture

  15. Review of Constructed Subsurface Flow vs. Surface Flow Wetlands

    SciTech Connect

    HALVERSON, NANCY

    2004-09-01

    The purpose of this document is to use existing documentation to review the effectiveness of subsurface flow and surface flow constructed wetlands in treating wastewater and to demonstrate the viability of treating effluent from Savannah River Site outfalls H-02 and H-04 with a subsurface flow constructed wetland to lower copper, lead and zinc concentrations to within National Pollutant Discharge Elimination System (NPDES) Permit limits. Constructed treatment wetlands are engineered systems that have been designed and constructed to use the natural functions of wetlands for wastewater treatment. Constructed wetlands have significantly lower total lifetime costs and often lower capital costs than conventional treatment systems. The two main types of constructed wetlands are surface flow and subsurface flow. In surface flow constructed wetlands, water flows above ground. Subsurface flow constructed wetlands are designed to keep the water level below the top of the rock or gravel media, thus minimizing human and ecological exposure. Subsurface flow wetlands demonstrate higher rates of contaminant removal per unit of land than surface flow (free water surface) wetlands, therefore subsurface flow wetlands can be smaller while achieving the same level of contaminant removal. Wetlands remove metals using a variety of processes including filtration of solids, sorption onto organic matter, oxidation and hydrolysis, formation of carbonates, formation of insoluble sulfides, binding to iron and manganese oxides, reduction to immobile forms by bacterial activity, and uptake by plants and bacteria. Metal removal rates in both subsurface flow and surface flow wetlands can be high, but can vary greatly depending upon the influent concentrations and the mass loading rate. Removal rates of greater than 90 per cent for copper, lead and zinc have been demonstrated in operating surface flow and subsurface flow wetlands. The constituents that exceed NPDES limits at outfalls H-02 a nd H

  16. Characteristics of Young Rhyolites at Taupo, New Zealand: Implications for the Sub-Surface Plutonic System

    NASA Astrophysics Data System (ADS)

    Wilson, C. J.; Charlier, B. L.

    2007-12-01

    The young history of Taupo volcano captures the growth and destruction in the 26.5 ka ca. 530 km3 Oruanui eruption of a large rhyolitic magma body, together with the subsequent rejuvenation of magma sources below the volcano. Integration of field information with petrological and isotopic studies at the whole-pumice and single- crystal scales provide a picture of this history. Several important contrasts are inferred to exist between Taupo and comparably-sized, long-lived silicic foci such at Long Valley and in the Bishop Tuff. At Taupo the following are demonstrable. 1. Even in crystal-poor rhyolites like the Oruanui, many grains are inherited antecrysts or xenocrysts. The Oruanui crystal-poor rhyolite body was an open system, with influxes of crystals (plus melt) from remobilised older crystal mush, melted metasedimentary country rocks and plutonics, and crystal-poor basaltic to andesitic magmas. 2. All the Taupo rhyolites were well mixed prior to eruption, and there are no gradients in the eruption products to suggest that the holding chamber(s) were stratified to any extent. 3. Mafic magmas rose into, interacted with, and ponded on the floors of crystal-poor rhyolite in the Oruanui and Waimihia (3.5 ka) examples, again implying that the chamber floor was sharply defined, not a gradual progression down into a more crystal- rich root zone. 4. Pre-Oruanui activity involved contrasting magma types being generated simultaneously, but erupting from geographically separated vents. Post-Oruanui activity has seen (subtly) contrasting magma groups being erupted from vents in the same geographic area, but separated in time. The Oruanui and post-Oruanui magmas are different and do not appear to be related by consanguinity or by mixing - the Oruanui eruption effectively destroyed its magma body. These features are consistent with rhyolite magma generation at Taupo that is exceptionally fast, driven by high fluxes of mafic magmas into a highly heterogeneous crustal melange

  17. Drainage subsidence associated with Arctic permafrost degradation

    NASA Astrophysics Data System (ADS)

    Lewis, K. C.; Zyvoloski, G. A.; Travis, B.; Wilson, C.; Rowland, J.

    2012-12-01

    Arctic sources of greenhouse gas associated with permafrost degradation constitute a large uncertainty in existing climate models. Greenhouse gas release from the Arctic subsurface is mediated by numerous interconnected physical processes; one facet of these is the interplay between surface deformation and melting of subsurface ice. First, we construct analytic solutions describing fluid drainage and soil subsidence subsequent to thawing of a 1-D permafrost column. These solutions lead to formulas giving the total amount of subsidence as well as the time over which subsidence occurs. We give an example application of the analytic model to peat plateau degradation in the Canadian Hudson Bay Lowland and show that the degree of subsidence predicted from our model is consistent with recorded subsidence of peat in western Norway that was drained for cultivation purposes. Second, we numerically model an initially frozen, fluid-saturated, 2-D soil matrix with a thaw zone advancing from the surface downward. With the surface temperature fixed at 5°C, a thaw front propagates to ˜10 m depth within 20 years, and due primarily to drainage of fluid from the pore space, a region of soil depressed by ˜3 m forms above an initially ice-rich subsurface zone. Soil underlying this depressed zone may have its permeability reduced by between 1 and 2 orders of magnitude; this reduction in permeability can act as a negative feedback to thawing.

  18. Sediment delivery from agricultural land to rivers via subsurface drainage

    NASA Astrophysics Data System (ADS)

    Chapman, A. S.; Foster, I. D. L.; Lees, J. A.; Hodgkinson, R. A.

    2005-10-01

    Diffuse sources of sediment and sediment-associated nutrients are of increasing environmental concern because of their impacts on receiving water courses. The aim of the research reported here was to monitor the outflow from four field (land) drains at two farms in the English Midlands in order to estimate the quantity of sediment delivered to the local rivers and the most likely sources and processes involved. A multiparameter sediment unmixing model was employed, using environmental magnetic, geochemical and radionuclide tracers in order to determine the most likely origin of sediments transported through the drains. Results demonstrated that there was a generally linear relationship between drainflow sediment loss and drainflow volume and that the majority (>70%) of the sediment exported from the drains was derived from topsoil. Macropore flow through heavily cracked soils is supported by the data to be the most likely means of sediment delivery to the drains. In one catchment, drains contributed over 50% of the annual sediment budget. Spatial and temporal variations in the sources of sediment reaching one drain outlet were investigated in detail. A link between soil moisture deficit (SMD) and the frequency of high-intensity rainfall events was used to explain the appearance and persistence of a new sediment source in this drain after October 1998. It is concluded that field drains have the potential to be significant conduits of sediment and agrochemicals in a wide variety of environments in the UK. It is also suggested that this potential may increase if projected climate change leads to more intense rainfall events and increases in SMD across a greater area of the UK.

  19. Martian drainage densities

    USGS Publications Warehouse

    Carr, M.H.; Chuang, F.C.

    1997-01-01

    Drainage densities on Mars range from zero over large areas of volcanic plains to 0.3-0.5 km-1 locally on some volcanoes. These values refer to geologic units, not to drainage basins, as is normal for terrestrial drainage densities. The highest values are close to the lowest terrestrial values derived by similar techniques. Drainage densities were determined for every geologic unit portrayed on the 1:15,000,000 geologic map of Mars. Except for volcanoes the geologic unit with the highest drainage density is the dissected Noachian plains with a drainage density of 0.0074 km-1. The average drainage density for Noachian units is 0.0032 km-1, for Hesperian units is 0.00047 km-1, and for Amazonian units is 0.00007 km-1, excluding the volcanoes. These values are 2-3 orders of magnitude lower than typical terrestrial densities as determined by similar techniques from Landsat images. The low drainage densities, despite a cumulative record that spans billions of years, indicate that compared with the Earth, the channel-forming processes have been very inefficient or have operated only rarely or that the surface is extremely permeable. The high drainage density on volcanoes is attributed to a local cause, such as hydrothermal activity, rather than to a global cause such as climate change. Copyright. Published in 1997 by the American Geophysical Union.

  20. Tangible Exploration of Subsurface Data

    NASA Astrophysics Data System (ADS)

    Petrasova, A.; Harmon, B.; Mitasova, H.; White, J.

    2014-12-01

    Since traditional subsurface visualizations using 2D maps, profiles or charts can be difficult to interpret and often do not convey information in an engaging form, scientists are interested in developing alternative visualization techniques which would help them communicate the subsurface volume data with students and general public. We would like to present new technique for interactive visualization of subsurface using Tangible geospatial modeling and visualization system (Tangeoms). It couples a physical, three-dimensional model with geospatial modeling and analysis through a cycle of scanning and projection. Previous applications of Tangeoms were exploring the impact of terrain modifications on surface-based geophysical processes, such as overland water flow, sediment transport, and also on viewsheds, cast shadows or solar energy potential. However, Tangeoms can serve as a tool for exploring subsurface as well. By creating a physical sand model of a study area, removing the sand from different parts of the model and projecting the computed cross-sections, we can look under the ground as if we were at an excavation site, and see the actual data represented as a 3D raster in that particular part of the model. Depending on data availability, we can also incorporate temporal dimension. Our method is an intuitive and natural way of exploring subsurface data and for users, it represents an alternative to more abstract 3D computer visualization tools, by offering direct, tangible interface.

  1. Subsurface Intrusion Detection System

    DTIC Science & Technology

    2014-02-25

    vibrations with a first sensor positioned at a first depth relative to a surface of the earth to generate a first signal and receiving vibrations...with a second sensor positioned at a second depth relative to the surface of the earth to generate a second signal. The second depth is greater than...to measure vibrations of the earth . The plurality of vibration sensors comprise at least an upper sensor and lower sensor at a location. Each signal

  2. Flow-band modeling of glacial erosion with a multi-morphology subglacial drainage system and process-based erosion laws

    NASA Astrophysics Data System (ADS)

    Beaud, F.; Flowers, G. E.

    2013-12-01

    Both field data and numerical modeling show that glaciations have the potential either to enhance relief or to dampen topography. While the processes by which glaciers erode have been recognized (i.e. abrasion, plucking, subglacial fluvial action), quantitative erosion models with predictive capability demand a better understanding of the processes themselves. We aim to model the effect of the subglacial hydraulic system on spatio-temporal patterns of glacial erosion, first on timescales commensurate with drainage system fluctuations (e.g. seasonal to interannual) and ultimately on timescales relevant to landscape evolution. We use a numerical model that incorporates a multi-morphology subglacial drainage system coupled to a higher-order ice-flow model and process-specific erosion laws for abrasion and quarrying. Ice flow is represented by a first-order approximation of the Stokes equations in two dimensions, while basal sliding is modeled using a Coulomb friction law. The subglacial drainage system allows for a dynamic transition between two morphologies: the distributed system characterized by an increase in basal water pressure with discharge, and the channelized system, which exhibits a decrease in equilibrium water pressure with increasing discharge. The resulting water pressure field is fed to the ice-flow model and both water pressure and sliding speed are used to calculate instantaneous erosion rates. Seasonal-scale simulations generally show that when subglacial hydrology is incorporated, modeled subglacial erosion rates peak where water input is significant, i.e. down-glacier from the equilibrium line. When both the distributed and channelized systems are integrated, the abrasion and sliding maxima migrate ~ 20% up-glacier compared to simulations with distributed drainage only. Once established, the channelized system evacuates water efficiently and reduces both water pressure and sliding rates across the lower reaches of the glacier; maximum rates of

  3. Using ground based geophysics to evaluate hydrogeologic effects of subsurface drip irrigation systems used to manage produced water in the Powder River Basin, Wyoming

    SciTech Connect

    Sams, J.I.; Lipinski, B.A.; Veloski, G.A.

    2008-04-01

    The U.S Department of Energy’s National Energy Technology Laboratory has been evaluating various geophysical methods for site characterization regarding environmental issues associated with fossil fuels including produced water management. A relatively new method of managing produced water from coal bed natural gas production is through subsurface drip irrigation. This system involves disposing the produced water near the bottom of the root zone in agricultural fields, which would provide a beneficial use of this resource. The focus of this paper is to present results from a pre-injection geophysical survey for site assessment and background data. A pre-construction survey of approximately 1.2 km2 was completed in June 2007 using a Geophex GEM-2 broadband sensor over six fields along the Powder River floodplain. Quality assurance measures included drift checks, duplicate line surveys, and repeat field surveys using the Geometrics OhmMapper instrument. Subsequent surveys will be completed once the system is installed and operational. Geophysical inversion models were completed to provide a detailed cross-section of the subsurface geoelectrical structure along each line. Preliminary interpretations reveal that the subsurface conductivity distribution correlates to geomorphologic features.

  4. Drainage water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article introduces a series of papers that report results of field studies to determine the effectiveness of drainage water management (DWM) on conserving drainage water and reducing losses of nitrogen (N) to surface waters. The series is focused on the performance of the DWM (also called contr...

  5. Percutaneous Abscess Drainage

    MedlinePlus

    ... the local anesthetic is injected. Most of the sensation is at the skin incision site which is numbed using local anesthetic. ... open surgical drainage. Risks Any procedure where the skin is penetrated ... organ may be damaged by percutaneous abscess drainage. Occasionally ...

  6. Biotreatment of mine drainage

    SciTech Connect

    Bender, J.; Phillips, R.

    1996-12-31

    Several experiments and field tests of microbial mats are described. One study determined the removal rate of Uranium 238 and metals from groundwater by microbial mats. Free floating mats, immobilized mats, excised mats, and pond treatment were examined. Field tests of acid coal mine drainage and precious metal mine drainage are also summarized. The mechanisms of metal removal are briefly described.

  7. Surface-to-subsurface temperature variations during the last century in a western boundary upwelling system (Southeastern, Brazil)

    NASA Astrophysics Data System (ADS)

    Venancio, Igor M.; Gomes, Vitor P.; Belem, Andre L.; Albuquerque, Ana Luiza S.

    2016-08-01

    The upper thermal gradient of a western boundary upwelling system was reconstructed for the last 100 years. The reconstruction was based on oxygen isotopic composition (δ18O) of four planktonic foraminifera species derived from two boxcores (BCCF10-01 and BCCF10-04) located in the southeastern Brazilian shelf. Calcification depths of the four planktonic foraminifera species were estimated in order to understand which layer of the water column was assessed. Changes in the upper thermal gradient were evaluated by using the δ18O difference from the surface-dwelling species Globigerinoides ruber (pink) and the deep-dwelling Neogloboquadrina dutertrei. The relative abundance of cold-water species and the δ13C of G. ruber (pink) were also used to evaluate changes on the surface layer. Our results demonstrate a trend to reduction on the temperature difference (∆T) between the surface and the thermocline layer towards the present for both cores, together with an increase on the relative abundance of cold-water species for the mid-shelf core (BCCF10-04) and a decrease in δ13C values of G. ruber (pink) for both cores. Despite the observable trend on the proxies, only the relative abundance of Turborotalita quinqueloba and the δ13C of G. ruber (pink) for the mid-shelf core presented statistically significant trends. These results were related to an increase in South Atlantic Central Water (SACW) intrusions in the sub-surface layer, especially on the middle shelf region. The SACW intrusions would lower the sea surface temperature and would bring a depleted δ13C of the dissolved inorganic carbon signature to the surface, which would be in agreement with our findings. Moreover, these mid-shelf SACW intrusions in the region were attributed to the Ekman pumping (wind stress curl-driven), which was previously reported to be an important mechanism in this upwelling system. The major outcomes to this western boundary current ecosystem from an intensification of the mid

  8. Structural and Paleoseismologic Characterization of Shallow, Subsurface Folding Above Segmented Blind-Thrust Systems Beneath Los Angeles, California

    NASA Astrophysics Data System (ADS)

    Leon, L. A.; Dolan, J. F.; Shaw, J. H.; Pratt, T. L.; Benesh, N. P.

    2008-12-01

    Over the past nine years we have been developing methodologies to understand the structural evolution and paleoearthquake history of blind thrust faults and their associated folds. To comprehend these issues our studies focused on two major blind thrust systems beneath metropolitan Los Angeles; the Puente Hills thrust fault (PHT) and the Compton fault. We acquired data from multiple study sites in order to analyze shallow subsurface folding for individual thrust ramps, as well as segmented thrust systems. Our research demonstrated that both the Puente Hills and Compton blind thrust faults have generated multiple, large- magnitude (Mw >7) earthquakes during the past 14 ka. In order to resolve how folds grow in response to slip on the underlying thrust ramps, we utilized a multidisciplinary approach, combining the acquisition of high-resolution seismic reflection profiles and borehole excavations across the overlying growth folds of major blind thrust faults. High-resolution seismic reflection profiles were acquired across the updip projection of the active axial fold surfaces located from petroleum industry seismic reflection profiles. These shallow seismic data allowed us to observe folding at multiple depths and identify discrete buried fold scarps at study sites above individual thrust ramps of both the PHT and Compton fault. The results of this research provided insights into the detailed kinematics of earthquake-by-earthquake fold growth above the underlying blind thrust ramps. At all our study sites, folds are well expressed as classic fault-bend folds growing predominantly by kink-band migration, generally as predicted by folding theory. In all examples, however, the borehole data show that the folded strata within the kink bands acquired their dips incrementally, suggesting that fold kinematics involves components of both kink-band migration and limb rotation. Based on discrete element models of this folding process, we suggest that these fold kinematics

  9. Foam consolidation and drainage.

    PubMed

    Jun, S; Pelot, D D; Yarin, A L

    2012-03-27

    A theoretical model of foam as a consolidating continuum is proposed. The general model is applied to foam in a gravity settler. It is predicted that liquid drainage from foam in a gravity settler begins with a slow drainage stage. Next, a stage with faster drainage occurs where the drainage rate doubles compared to the initial stage. The experiments conducted within the framework of this work confirmed the theoretical predictions and allowed measurements of foam characteristics. Foams of three different concentrations of Pantene Pro-V Classic Care Solutions shampoo were studied, as well as the addition of polyethylene oxide (PEO) in one case. The shampoo's main foaming components are sodium lauryl sulfate and sodium laureth sulfate. It is shown to what extent foam drainage is slowed down by using higher shampoo concentrations and how it is further decreased by adding polymer (PEO).

  10. Modeling of subglacial hydrological development following rapid supraglacial lake drainage

    PubMed Central

    Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

    2015-01-01

    The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Key Points Model for subglacial hydrological analysis of rapid lake drainage events Limited subglacial channel growth during and following rapid lake drainage Persistence of distributed drainage in inland areas where channel growth is limited PMID:26640746

  11. Modeling spatially and temporally varied hydraulic behavior of a folded karst system with dominant conduit drainage at catchment scale, Hochifen-Gottesacker, Alps

    NASA Astrophysics Data System (ADS)

    Chen, Zhao; Goldscheider, Nico

    2014-06-01

    Karst aquifers are important for freshwater supply, but difficult to manage, due to highly variable water levels and spring discharge rates. Conduits are crucial for groundwater flow in karst aquifers, but their location is often unknown, thus limiting the applicability and validity of numerical models. We have applied a conduit model (SWMM) to simulate highly variable flow in a folded alpine karst aquifer system, where the underground drainage pattern is comparatively well-known from previous tracer studies. The conduit model was coupled with a reservoir model representing recharge, storage and transfer of water in the epikarst and unsaturated zone. The global optimization approach (GA) was applied to achieve an efficient model calibration. It was possible to simultaneously simulate the highly variable discharge characteristics of an estavelle, and overflow spring and a permanent spring draining the conduit system. The model allowed for the collection of spatially differentiated information on recharge, rapid flow and slow flow in four individual sub-catchments. The formation of backwater upgradient from conduit restrictions turned out to be a key process in activating overflow springs. The proposed modeling approach appears to be transferrable to other karst systems with predominant conduit drainage, but requires previous knowledge of the configuration of the conduit system.

  12. Sedimentary record of a Scandinavian Ice Sheet drainage system and till deposition over subglacial obstacles promoting basal sliding (an example from southern Poland)

    NASA Astrophysics Data System (ADS)

    Salamon, Tomasz

    2015-12-01

    Subglacial obstacles occurring in the path of advancing ice sheets generally generate higher longitudinal compression and higher frictional drag than a flat substrate. However, in the case of a soft sediment substratum, they can have a very different effect on ice sheet behaviour. This study concerns a substrate composed of very fine-grained sediments with low permeability. The relationship between subglacial obstacles and the overriding Scandinavian Ice Sheet was studied in an area of southern Poland where a small intervalley Neogene clay ridge (40 m high) was present. Based on sedimentological and structural analysis of subglacial till and gravelly-sandy sediments, the basal depositional processes and subglacial conditions and their influence on ice sheet behaviour were analysed. The till and related deposits within the ridge reflecting high water pressure conditions and lack of glacitectonic deformations indicate that the clay ridge did not generate much resistance against the advancing ice sheet, but instead favoured basal slip: the impermeable substratum weakened the ice/bed coupling and promoted ice detachment from the substratum. Gravelly sandy inclusions at the till/clay contact indicate that during the first stage of ice sheet overriding, a canal drainage system developed at the ice/substrate interface. Varied geometry, size and location of inclusions of sorted sediments suggest periodic instability of the canal system, which could lead to its transformation from initially uniform to being composed of conduits of different sizes. During later stages of ice sheet overriding, a traction till was deposited and occasional drainage through a water film was sufficient to evacuate basal meltwater. The resulting change in the character of subglacial drainage was probably related to variations in water pressure gradient during progressive ice sheet advance.

  13. Containment of subsurface contaminants

    DOEpatents

    Corey, J.C.

    1994-09-06

    A barrier is disclosed for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates. 5 figs.

  14. Containment of subsurface contaminants

    DOEpatents

    Corey, John C.

    1994-01-01

    A barrier for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates.

  15. Drainage reorganization during mountain building in the river system of the Eastern Cordillera of the Colombian Andes

    NASA Astrophysics Data System (ADS)

    Struth, Lucía; Babault, Julien; Teixell, Antonio

    2015-12-01

    The Eastern Cordillera of Colombia is a thick-skinned thrust-fold belt that is characterized by two topographic domains: (1) the axial zone, a high altitude plateau (the Sabana de Bogotá, 2500 masl) with low local relief and dominated by longitudinal rivers, and (2) the Cordillera flanks, where local relief exceeds 1000 m and transverse rivers dominate. On the basis of an analysis of digital topography and river parameters combined with a review of paleodrainage data, we show that the accumulation of shortening and crustal thickening during the Andean orogeny triggered a process of fluvial reorganization in the Cordillera. Owing to a progressive increase of the regional slope, the drainage network evolves from longitudinal to transverse-dominated, a process that is still active at present. This study provides the idea of progressive divide migration toward the inner part of the mountain belt, by which the area of the Sabana de Bogotá plateau is decreasing, the flanks increase in area, and ultimately transverse rivers will probably dominate the drainage of the Cordillera.

  16. Ear drainage culture

    MedlinePlus

    ... needed. Your health care provider will use a cotton swab to collect the sample from inside the ... Using a cotton swab to take a sample of drainage from the outer ear is not painful. However, ear pain may ...

  17. Subsurface fluids screening by an analytical system employing a diffusion-limited and implantable sampling module deployable with a cone penetrometer

    SciTech Connect

    Lucero, D.P.; Ilgner, R.H.; Smith, R.R.; Jenkins, R.A.

    1997-03-01

    An analytical system employing a diffusion-limited sampling module and a direct sampling ion trap for quantitative assessment of subsurface fluids was developed and field tested. The sampling module is deployable with a cone penetrometer. It can be retrieved and/or remain as an implant for an indefinite time period. The device geometry, comprised of two planar membranes enclosing a diffusion cell, provides good implant ruggedness and reliable service in the field. Also, the sampling module is protected within a push pipe housing to extend implant service life. Subsurface volatile organic compound (VOC) vapors, in nanoliter amounts, diffuse through the sampler membrane wall by a diffusion-limited process that is independent of the soil permeability. Sample vapors are transported to the surface for analysis by direct sampling ion trap, or other analytical devices. Metered pressurized or reduced pressure transport (carrier) gas is utilized for sample transport to the surface. The vapors obtained are a function only of the fluid partial pressure and the vapor conductance of the sampler. Thus, quantitative analytical data is obtained regardless of soil conditions. The sampling module was deployed in the field at Dover Air Force Base at depths of 5 to 8.5 feet by the US Army Site Characterization and Analysis Penetrometer System (SCAPS). Relatively small 1.75 inch diameter push pipe and the relatively small vapor samples extracted cause minimal soil disturbance which preserves the integrity of the sampler subsurface surroundings. Analytical results were obtained for the system sampler operating in real time and as an implant where equilibrium was obtained between sampler interior and the external surroundings.

  18. Simulating the Effects of Drainage and Agriculture on Hydrology and Sediment in the Minnesota River Basin

    NASA Astrophysics Data System (ADS)

    Downer, C. W.; Pradhan, N. R.; Skahill, B. E.; Banitt, A. M.; Eggers, G.; Pickett, R. E.

    2014-12-01

    Throughout the Midwest region of the United States, slopes are relatively flat, soils tend to have low permeability, and local water tables are high. In order to make the region suitable for agriculture, farmers have installed extensive networks of ditches to drain off excess surface water and subsurface tiles to lower the water table and remove excess soil water in the root zone that can stress common row crops, such as corn and soybeans. The combination of tiles, ditches, and intensive agricultural land practices radically alters the landscape and hydrology. Within the watershed, tiles have outlets to both the ditch/stream network as well as overland locations, where the tile discharge appears to initiate gullies and exacerbate overland erosion. As part of the Minnesota River Basin Integrated Study we are explicitly simulating the tile and drainage systems in the watershed at multiple scales using the physics-based watershed model GSSHA (Gridded Surface Subsurface Hydrologic Analysis). The tile drainage system is simulated as a network of pipes that collect water from the local water table. Within the watershed, testing of the methods on smaller basins shows the ability of the model to simulate tile flow, however, application at the larger scale is hampered by the computational burden of simulating the flow in the complex tile drain networks that drain the agricultural fields. Modeling indicates the subsurface drains account for approximately 40% of the stream flow in the Seven Mile Creek sub-basin account in the late spring and early summer when the tile is flowing. Preliminary results indicate that agricultural tile drains increase overland erosion in the Seven Mile Creek watershed.

  19. Paleohydrology of meandering systems: a new approach for the reconstruction of ancient drainage areas and the quantification of the controlling factors

    NASA Astrophysics Data System (ADS)

    Held, A.; Cojan, I.

    2009-12-01

    In meandering system fluvial sedimentology, studying infill geometries and sedimentary structures of channelized sandstone bodies, gives information about the sedimentary dynamic and the depositional environment. Associated with such a sedimentary approach, paleohydrology enables the reconstruction of hydrological parameters such as discharge, drainage area or stream length. Although fluvial systems are known to be influenced by allogenic and/or autogenic processes, climate or structural evolution were not taken into account in previous paleohydrological studies. Therefore, the present study attempts to develop a new method of paleohydrological reconstitution, based on the geometry of fluvial sandstone bodies and constrained by the controlling factors (climate and tectonic). We selected two meandering systems of the same age, developed under different climatic setting: the first one is located in the Alpine Foreland Basin (SE France) and was associated to a subtropical humid realm; the second one is situated in the Loranca Basin (Central Spain) and was related to subtropical semi-arid conditions. Dealing with the uniformitarianism concept, we developed a new method to determine the paleohydrological parameters of the two different systems. For each of these two climatic setting we have constructed an equivalent modern rivers database taking into account their respective climatic conditions. By defining empirical relations, we translated the point-bar thickness (the only data available in the field) into paleohydrological parameters, such as channel geometry, water discharge and basin geometry. Because fluvial members studied are composed of several channelized sequences; each of them gives a specific drainage area depending on discharge value and climatic coefficient. But assuming a constant basin area all along the river evolution, we can quantify the spatiotemporal impact of the climate on the development of an alluvial system. Furthermore, granulometry

  20. Geochemical behavior of an acid drainage system: the case of the Amarillo River, Famatina (La Rioja, Argentina).

    PubMed

    Lecomte, K L; Maza, S N; Collo, G; Sarmiento, A M; Depetris, P J

    2017-01-01

    The Amarillo River (Famatina range, Argentina, ~29° S and ~67° W) is unusual because acid mine drainage (AMD) is superimposed on the previously existing acid rock drainage (ARD) scenario, as a Holocene paleolake sedimentary sequence shows. In a markedly oxidizing environment, its water is currently ferrous and of the sulfate-magnesium type with high electrical conductivity (>10 mS cm(-1) in uppermost catchments). At the time of sampling, the interaction of the mineralized zone with the remnants of mining labors determined an increase in some elements (e.g., Cu ~3 to ~45 mg L(-1); As ~0.2 to ~0.5 mg L(-1)). Dissolved concentrations were controlled by pH, decreasing significantly by precipitation of neoformed minerals (jarosite and schwertmannite) and subsequent metal sorption (~700 mg kg(-1) As, 320 mg kg(-1) Zn). Dilution also played a significant role (i.e., by the mixing with circumneutral waters which reduces the dissolved concentration and also enhances mineral precipitation). Downstream, most metals exhibited a significant attenuation (As 100 %, Fe 100 %, Zn 99 %). PHREEQC-calculated saturation indices (SI) indicated that Fe-bearing minerals, especially schwertmannite, were supersaturated throughout the basin. All positive SI increased through the input of circumneutral water. PHREEQC inverse geochemical models showed throughout the upper and middle basin, that about 1.5 mmol L(-1) of Fe-bearing minerals were precipitated. The modeling exercise of mixing different waters yielded results with a >99 % of correlation between observed and modeled data.

  1. Data on quantity and quality of water flowing in drainage systems of dry docks at Puget Sound Naval Shipyard, Bremerton, Washington, 1994

    USGS Publications Warehouse

    Prych, E.A.

    1995-01-01

    Ground-water discharges into dry docks no. 1, 2, 3, 4, 5 and 6 of Puget Sound Naval Shipyard in Bremerton, Washington equalled 0.07, 0.30, 0.29, 0.61, 1.18 and 6.2 cubic feet per second during one set of measurements in the summer of 1994. Total drainage-water discharges from the dry docks equalled 0.07, 0.30, 0.33, 0.61, 1.36 and 11.7 cubic feet per second. Differences between the two sets of discharges were cofferdam and floodgate leakages into the dry docks, and in dry dock no. 6, cooling- water discharge from a ship in dry dock. Concen- trations of total copper and total lead at 36 sampling sites in the drainage systems ranged from less than 1 to 71 micrograms per liter and less than 1 to 44 micrograms per liter, respectively. Concen- trations of all 43 semi-volatile organic compounds analyzed for in samples from 19 sites were less than the laboratory minimum reporting level (5 or 10 micrograms per liter). Trichloroethene and at least three other volatile organic compounds were found at concentrations greater than 0.2 micrograms per liter in samples from all eight sites that were analyzed for 63 volatile organic compounds.

  2. Effect of glacial drainage water on the CO2 system and ocean acidification state in an Arctic tidewater-glacier fjord during two contrasting years

    NASA Astrophysics Data System (ADS)

    Fransson, Agneta; Chierici, Melissa; Nomura, Daiki; Granskog, Mats A.; Kristiansen, Svein; Martma, Tõnu; Nehrke, Gernot

    2015-04-01

    In order to investigate the effect of glacial water on the CO2 system in the fjord, we studied the variability of the total alkalinity (AT), total dissolved inorganic carbon (CT), dissolved inorganic nutrients, oxygen isotopic ratio (δ18O), and freshwater fractions from the glacier front to the outer Tempelfjorden on Spitsbergen in winter 2012 (January, March, and April) and 2013 (April) and summer/fall 2013 (September). The two contrasting years clearly showed that the influence of freshwater, mixing, and haline convection affected the chemical and physical characteristics of the fjord. The seasonal variability showed the lowest calcium carbonate saturation state (Ω) and pH values in March 2012 coinciding with the highest freshwater fractions. The highest Ω and pH were found in September 2013, mostly due to CO2 uptake during primary production. Overall, we found that increased freshwater supply decreased Ω, pH, and AT. On the other hand, we observed higher AT relative to salinity in the freshwater end-member in the mild and rainy winter of 2012 (1142 μmol kg-1) compared to AT in 2013 (526 μmol kg-1). Observations of calcite and dolomite crystals in the glacial ice suggested supply of carbonate-rich glacial drainage water to the fjord. This implies that winters with a large amount of glacial drainage water partly provide a lessening of further ocean acidification, which will also affect the air-sea CO2 exchange.

  3. Title III Evaluation Report for the Subsurface Fire Water System and Subsurrface Portion of the Non-Portable Water System

    SciTech Connect

    R.E. Flye

    1998-09-29

    The objective of this evaluation is to provide recommendations to ensure consistency between the technical baseline requirements, baseline design, and the as-constructed SFWS/SNPWS. Recommendations for resolving discrepancies between the as-constructed systems, the technical baseline requirements, and the baseline design are included in this report. Cost and schedule estimates are provided for all recommended modifications. This report does not address items which do not meet current safety or code requirements. These items are identified to the CMO and immediate action is taken to correct the situation. The report does identify safety and code items for which the A/E is recommending improvements. The recommended improvements will exceed the minimum requirements of applicable code and safety guidelines. These recommendations are intended to improve and enhance the operation and maintenance of the facility.

  4. Tile drainage as karst: Conduit flow and diffuse flow in a tile-drained watershed

    USGS Publications Warehouse

    Schilling, K.E.; Helmers, M.

    2008-01-01

    The similarity of tiled-drained watersheds to karst drainage basins can be used to improve understanding of watershed-scale nutrient losses from subsurface tile drainage networks. In this study, short-term variations in discharge and chemistry were examined from a tile outlet collecting subsurface tile flow from a 963 ha agricultural watershed. Study objectives were to apply analytical techniques from karst springs to tile discharge to evaluate water sources and estimate the loads of agricultural pollutants discharged from the tile with conduit, intermediate and diffuse flow regimes. A two-member mixing model using nitrate, chloride and specific conductance was used to distinguish rainwater versus groundwater inputs. Results indicated that groundwater comprised 75% of the discharge for a three-day storm period and rainwater was primarily concentrated during the hydrograph peak. A contrasting pattern of solute concentrations and export loads was observed in tile flow. During base flow periods, tile flow consisted of diffuse flow from groundwater sources and contained elevated levels of nitrate, chloride and specific conductance. During storm events, suspended solids and pollutants adhered to soil surfaces (phosphorus, ammonium and organic nitrogen) were concentrated and discharged during the rapid, conduit flow portion of the hydrograph. During a three-day period, conduit flow occurred for 5.6% of the time but accounted for 16.5% of the total flow. Nitrate and chloride were delivered primarily with diffuse flow (more than 70%), whereas 80-94% of total suspended sediment, phosphorus and ammonium were exported with conduit and intermediate flow regimes. Understanding the water sources contributing to tile drainage and the manner by which pollutant discharge occurs from these systems (conduit, intermediate or diffuse flow) may be useful for designing, implementing and evaluating non-point source reduction strategies in tile-drained landscapes. ?? 2007 Elsevier B.V. All

  5. Hydrologic budget of the late Oligocene Lake Creede and the evolution of the upper Rio Grande drainage system

    USGS Publications Warehouse

    Barton, Paul B.; Steven, Thomas A.; Hayba, Daniel O.

    2000-01-01

    drilling) formed in an euxinic environment. This argues against a persistent early playa, although evaporative accumulation of brine was inevitable. When the rate of resurgance was rapid relative to sedimentary infilling, the lake would have been deep (i.e., bordered by bedrock rather than sedimentary fans). The geomorphic evolution of the Creede caldera and its watershed tracks a two-phase topographic history, the first the Oligocene through Miocene, and the second for Pliocene to the recent. In Oligocene time, the San Juan volcanic field was a hydrologically immature, gently undulating, and outward sloping, constructional volcanic plateau straddling the ancient Continental Divide. West of the Creede caldera, a dendritic drainage discharged northeastward into ancestral Cebolla Creek (a tributary of the ancestral Gunnison River) through an early stage of the Clear Creek graben in the vicinity of Spring Creek Pass. Miocene basalt choked, but did not reconstruct, the drainage. By the end of Miocene time a mature topography of moderate relief developed, exposing some of the higher ores in the Creede district to weathering. In the late Miocene-early Pliocene time the San Juan Mountains were uplifted and titled eastward; the ancestral Rio Grande was revitalized and cut deeply into the older terrain, excavating much of the accessible sediment from the moat of the Creede caldera and exposing successively lowe levels in the Creede district to oxidation. Simultaneously, the southeast end of the Clear Creek graben was reactivated and breached the southwest wall of the Creede caldera. The rejuvenated Rio Grande captured the formerly northeast-directed headwaters of ancestral Cebolla Creek, shifting more than 1000 km2 from the Pacific-directed drainage to the Atlantic. The water budget for ancient Lake Creede was strictly limited by the early stages of the fist geomorphic cycle; the modern water budget is the product of the second cycle.

  6. Method of installing subsurface barrier

    SciTech Connect

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2007-10-09

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  7. Subsurface Microbiology and Biogeochemistry

    SciTech Connect

    Fredrickson, Jim K.; Fletcher, Madilyn

    2001-05-01

    Jim contributed a chapter to this book, in addition to co-editing it with Madilyn Fletcher. Fredrickson, J. K., and M. Fletcher. (eds.) 2001 Subsurface Microbiology and Biogeochemistry. Wiley-Liss, Inc., New York.

  8. Ceramic subsurface marker prototypes

    SciTech Connect

    Lukens, C.E.

    1985-05-02

    The client submitted 5 sets of porcelain and stoneware subsurface (radioactive site) marker prototypes (31 markers each set). The following were determined: compressive strength, thermal shock resistance, thermal crazing resistance, alkali resistance, color retention, and chemical resistance.

  9. Deep subsurface microbial processes

    USGS Publications Warehouse

    Lovley, D.R.; Chapelle, F.H.

    1995-01-01

    Information on the microbiology of the deep subsurface is necessary in order to understand the factors controlling the rate and extent of the microbially catalyzed redox reactions that influence the geophysical properties of these environments. Furthermore, there is an increasing threat that deep aquifers, an important drinking water resource, may be contaminated by man's activities, and there is a need to predict the extent to which microbial activity may remediate such contamination. Metabolically active microorganisms can be recovered from a diversity of deep subsurface environments. The available evidence suggests that these microorganisms are responsible for catalyzing the oxidation of organic matter coupled to a variety of electron acceptors just as microorganisms do in surface sediments, but at much slower rates. The technical difficulties in aseptically sampling deep subsurface sediments and the fact that microbial processes in laboratory incubations of deep subsurface material often do not mimic in situ processes frequently necessitate that microbial activity in the deep subsurface be inferred through nonmicrobiological analyses of ground water. These approaches include measurements of dissolved H2, which can predict the predominant microbially catalyzed redox reactions in aquifers, as well as geochemical and groundwater flow modeling, which can be used to estimate the rates of microbial processes. Microorganisms recovered from the deep subsurface have the potential to affect the fate of toxic organics and inorganic contaminants in groundwater. Microbial activity also greatly influences 1 the chemistry of many pristine groundwaters and contributes to such phenomena as porosity development in carbonate aquifers, accumulation of undesirably high concentrations of dissolved iron, and production of methane and hydrogen sulfide. Although the last decade has seen a dramatic increase in interest in deep subsurface microbiology, in comparison with the study of

  10. Phase diagram and density of fluids in the water-methanol system: experiments and implications for the crystallization and dynamics of subsurface oceans in icy moons

    NASA Astrophysics Data System (ADS)

    Yao, C.; Mantegazzi, D.; Deschamps, F.; Sanchez-Valle, C.

    2013-12-01

    Methanol, CH3OH, has been recently observed in several comets and at the surface of Saturn's icy moon Enceladus, [Hodyss et al., 2009]. Its plausible presence in the subsurface ocean could significantly affect the thermal and structural evolution of the satellite [Deschamps et al., 2010]. Methanol lowers the melting temperature of water ice [Vuillard & Sanchez, 1961; Miller & Carpenter, 1964], hence decreasing the efficiency of convective heat transfer through the outer ice Ih shell, and affects the subsurface ocean density and thermo-chemical evolution. However, the phase diagram and the fluid density of the H2O - CH3OH system remains largely unknown at the high pressures and low temperature conditions relevant for the icy moon interiors. In this study, we determined experimentally the liquidus temperature of Ice Ih and Ice VI and the fluid density in the binary water-methanol system (5, 10 and 20 w% CH3OH) from sound velocity measurments by Brillouin scattering spectroscopy over the P-T range 230 - 300 K and 10-4 - 1.2 GPa. The experiments were conducted using a membrane-type diamond anvil cell (mDAC) and an in-house designed Peltier cooling system to achieve the low temperatures of interest. Melting and crystallization in the system was visually monitored and confirmed from changes in the Brillouin spectra and in the pressure dependence of the measured sound velocities. The density of fluids ρ(P, T,x) in the binary system weas determined from the inversion of sound velocities measured in the fluids as a function of pressure along isotherms from 230 to 300 K. The results are used to propose a thermodynamic model for the CH3OH-H2O system over the investigated P-T range and further used to examine the effect of the methanol on the crystallization and thermo-chemical evolution of the subsurface ocean. The implications of these results for the thermal and structural evolution of icy moons, with particular applications to Titan, will be further discussed. References

  11. Analysis of effects of climate change on runoff in an urban drainage system: a case study from Seoul, Korea.

    PubMed

    Jung, M; Kim, H; Mallari, K J B; Pak, G; Yoon, J

    2015-01-01

    Both water quantity and quality are impacted by climate change. In addition, rapid urbanization has also brought an immeasurable loss of life and property resulting from floods. Hence, there is a need to predict changes in rainfall events to effectively design stormwater infrastructure to protect urban areas from disaster. This study develops a framework for predicting future short duration rainfall intensity and examining the effects of climate change on urban runoff in the Gunja Drainage Basin. Non-stationarities in rainfall records are first analysed using trend analysis to extrapolate future climate change scenarios. The US Environmental Protection Agency Storm Water Management Model (SWMM) was used for single event simulation of runoff quantity from the study area. For the 1-hour and 24-hour durations, statistically significant upward trends were observed. Although the 10-minute duration was only nearly significant at the 90% level, the steepest slope was observed for this short duration. Moreover, it was observed that the simulated peak discharge from SWMM increases as the short duration rainfall intensity increases. The proposed framework is thought to provide a means to review the current design of stormwater infrastructures to determine their capacity, along with consideration of climate change impact.

  12. A Comparison of "Ice-House" (Modern) and "Hot-House" (Maastrichtian) Drainage Systems: the Implications of Large-Scale Changes in the Surface Hydrological Scheme

    NASA Astrophysics Data System (ADS)

    Markwick, P. J.; Crossley, R.; Valdes, P. J.

    2002-12-01

    A GIS analysis of modern and Maastrichtian (Late Cretaceous) drainage systems has been made in order to investigate the potential differences between the surface hydrology of "ice-house" and "hot-house" worlds and how this might be reflected in the geological record. Because of the importance of CO2 concentrations for generating "hot-house" climates this study also has implications for potential future changes in the climate system. For the modern system we have utilized global maps of observed river systems, the Hydro1K digital dataset, observations of freshwater and sediment fluxes from recording stations, and modern day climate models and observations. For the Maastrichtian we have compiled a detailed global paleogeographic map and geological database (based on earlier work by the Paleogeographic Atlas Project, University of Chicago) that has been used to generate a paleo-DEM using the suite of hydrological tools in ArcGIS, complete with reconstructed river systems and drainage basins. This forms the primary boundary condition for a coupled ocean-atmosphere experiment using the HadCM3 model, with atmospheric CO2 set at 4 x pre-industrial levels. The results indicate a Maastrichtian world dominated by high sea surface temperatures (as high as 30-35 C in the tropics), and a consequently greatly enhanced hydrological cycle when compared with the Present. Globally, modeled Maastrichtian precipitation and evaporation are 1.5x that for the Present, with a 2.5x increase in total runoff. These changes are not evenly distributed, either spatially or seasonally, and therefore a detailed consideration of the paleogeography and paleo-drainage is essential, as these changes have a major influence on the distribution of vegetation and freshwater and sediment fluxes. For example, the Maastrichtian Tethyan monsoon, though less intense than noted for other modeled Mesozoic intervals, nonetheless dominates the seasonal distribution of precipitation and runoff over Saharan and

  13. Drainage networks after wildfire

    USGS Publications Warehouse

    Kinner, D.A.; Moody, J.A.

    2005-01-01

    Predicting runoff and erosion from watersheds burned by wildfires requires an understanding of the three-dimensional structure of both hillslope and channel drainage networks. We investigate the small-and large-scale structures of drainage networks using field studies and computer analysis of 30-m digital elevation model. Topologic variables were derived from a composite 30-m DEM, which included 14 order 6 watersheds within the Pikes Peak batholith. Both topologic and hydraulic variables were measured in the field in two smaller burned watersheds (3.7 and 7.0 hectares) located within one of the order 6 watersheds burned by the 1996 Buffalo Creek Fire in Central Colorado. Horton ratios of topologic variables (stream number, drainage area, stream length, and stream slope) for small-scale and large-scale watersheds are shown to scale geometrically with stream order (i.e., to be scale invariant). However, the ratios derived for the large-scale drainage networks could not be used to predict the rill and gully drainage network structure. Hydraulic variables (width, depth, cross-sectional area, and bed roughness) for small-scale drainage networks were found to be scale invariant across 3 to 4 stream orders. The relation between hydraulic radius and cross-sectional area is similar for rills and gullies, suggesting that their geometry can be treated similarly in hydraulic modeling. Additionally, the rills and gullies have relatively small width-to-depth ratios, implying sidewall friction may be important to the erosion and evolutionary process relative to main stem channels.

  14. Integration of Ground Penetrating Radar with Real Time Kinematic - Global Positioning System Receivers for Efficient Mapping of Drainage Pipe Systems Beneath Golf Course Greens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The U.S. alone has over 16,000 golf course facilities. The upkeep of these facilities requires continual maintenance and occasional remodeling. The superintendents and architects responsible for golf course maintenance and remodeling efforts need non-destructive tools for obtaining shallow subsurfac...

  15. Floating insulated conductors for heating subsurface formations

    DOEpatents

    Burns, David; Goodwin, Charles R.

    2014-07-29

    A heating system for a subsurface formation includes a conduit located in a first opening in the subsurface formation. Three electrical conductors are located in the conduit. A return conductor is located inside the conduit. The return conductor is electrically coupled to the ends of the electrical conductors distal from the surface of the formation. Insulation is located inside the conduit. The insulation electrically insulates the three electrical conductors, the return conductor, and the conduit from each other.

  16. Potential hydrologic effects of a drainage system in McMillan delta and water impoundment in Brantley Reservoir, Eddy County, New Mexico

    USGS Publications Warehouse

    Crouch, T.M.; Welder, G.E.

    1988-01-01

    Construction of a proposed drainage system could result in a moderate flow increase in the Pecos River downstream from the McMillan delta. The potential effect of a new line channel of the Pecos River in McMillan delta in southeastern New Mexico would be an increase of less than 11,000 acre-ft/year. This increase includes overflow of 300 acre-ft from the present Pecos River channel, seepage losses of 3,600 acre-ft from the river bed and tributary inflow of 7,100 acre-ft. The potential effects of drains at the north end of the study area would be additional water of about 6,100 acre-ft within the first few years. In order to drain this much water, the drains would have to be dredged to a lower depth 6 to 8 mi to the south. Impoundment in Brantley Reservoir will cause increases in groundwater storage. The quantity of increased storage will depend on average reservoir pool levels. Major Johnson Springs probably will cease to flow at the conservation-pool level, and southward groundwater leakage from the Major Johnson Springs aquifer could increase. Large quantities of water may move in and out of storage in the Major Johnson Springs aquifer as the Brantley Reservoir pool changes between minimum pool and conservation pool levels. A ground--and surface-water monitoring network is needed to determine changes in groundwater storage caused by Brantley Reservoir. Water levels in selected wells need to be measured periodically during operation of the reservoir. Additional streamflow-gaging stations need to be established and surface-water samples analyzed to determine changes caused by a drainage system and Brantley Reservoir. (USGS)

  17. Capillarity and wetting of carbon dioxide and brine during drainage in Berea sandstone at reservoir conditions

    NASA Astrophysics Data System (ADS)

    Al-Menhali, Ali; Niu, Ben; Krevor, Samuel

    2015-10-01

    The wettability of CO2-brine-rock systems will have a major impact on the management of carbon sequestration in subsurface geological formations. Recent contact angle measurement studies have reported sensitivity in wetting behavior of this system to pressure, temperature, and brine salinity. We report observations of the impact of reservoir conditions on the capillary pressure characteristic curve and relative permeability of a single Berea sandstone during drainage—CO2 displacing brine—through effects on the wetting state. Eight reservoir condition drainage capillary pressure characteristic curves were measured using CO2 and brine in a single fired Berea sandstone at pressures (5-20 MPa), temperatures (25-50°C), and ionic strengths (0-5 mol kg-1 NaCl). A ninth measurement using a N2-water system provided a benchmark for capillarity with a strongly water wet system. The capillary pressure curves from each of the tests were found to be similar to the N2-water curve when scaled by the interfacial tension. Reservoir conditions were not found to have a significant impact on the capillary strength of the CO2-brine system during drainage through a variation in the wetting state. Two steady-state relative permeability measurements with CO2 and brine and one with N2 and brine similarly show little variation between conditions, consistent with the observation that the CO2-brine-sandstone system is water wetting and multiphase flow properties invariant across a wide range of reservoir conditions.

  18. A statistical approach for the assessment and redesign of the Nile Delta drainage system water-quality-monitoring locations.

    PubMed

    Khalil, B; Ouarda, T B M J; St-Hilaire, A

    2011-08-01

    There are several deficiencies in the statistical approaches proposed in the literature for the assessment and redesign of surface water-quality-monitoring locations. These deficiencies vary from one approach to another, but generally include: (i) ignoring the attributes of the basin being monitored; (ii) handling multivariate water quality data sequentially rather than simultaneously; (iii) focusing mainly on locations to be discontinued; and (iv) ignoring the reconstitution of information at discontinued locations. In this paper, a methodology that overcomes these deficiencies is proposed. In the proposed methodology, the basin being monitored is divided into sub-basins, and a hybrid-cluster analysis is employed to identify groups of sub-basins with similar attributes. A stratified optimum sampling strategy is then employed to identify the optimum number of monitoring locations at each of the sub-basin groups. An aggregate information index is employed to identify the optimal combination of locations to be discontinued. The proposed approach is applied for the assessment and redesign of the Nile Delta drainage water quality monitoring locations in Egypt. Results indicate that the proposed methodology allows the identification of (i) the optimal combination of locations to be discontinued, (ii) the locations to be continuously measured and (iii) the sub-basins where monitoring locations should be added. To reconstitute information about the water quality variables at discontinued locations, regression, artificial neural network (ANN) and maintenance of variance extension (MOVE) techniques are employed. The MOVE record extension technique is shown to result in a better performance than regression or ANN for the estimation of information about water quality variables at discontinued locations.

  19. [Drainage in thyroid surgery].

    PubMed

    Ardito, G; Revelli, L; Guidi, M L; Murazio, M; Lucci, C; Modugno, P; Di Giovanni, V

    1999-01-01

    Bleeding represents a rare complication of thyroid surgery but when it occurs it may be life-threatening. To prevent this complication drainage is widely used. However no study has demonstrated the drains' value and recent reports have questioned its benefits. Therefore we have analyzed our experience of a 10 year-period in which 1.217 thyroidectomies were performed by the same surgical team and prophylactic routine drainage was always adopted. In 13 patients (1.06%) a benign hematoma occurred with spontaneous remission. In 6 patients the bleeding was severe and compressive hematoma occurred; it required surgical re-exploration. Such a complication is unusual in the neck surgery (0.49% in the authors' series) performed by experienced surgeons and when life-threatening hematomas do occur they depend on various uncontrolled factors and drainage is often not helpful. Otherwise a meticulous haemostatic technique is necessary and patients should be observed very closely during the few first hours following surgery on the thyroid gland. Therefore on the basis of the analysis of their series, although it is not always possible to prove the benefit of the drainage, the authors suggest its indication in the neck surgery, as in other fields with dead space, to remove blood and secretions reducing postoperative complications. They have never observed wound infections and patients were discharged within 72 hours.

  20. Drainage Water Filtration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tile drainage discharge from managed turf is known to carry elevated concentrations of agronomic fertilizers and chemicals. One approach being considered to reduce the transport is end-of-tile-filters. Laboratory and field studies have been initiated to address the efficacy of this approach. Result...

  1. Holocene ochreous lacustrine sediments within the Famatina Belt, NW Argentina: A natural case for fossil damming of an acid drainage system

    NASA Astrophysics Data System (ADS)

    Maza, Santiago N.; Collo, Gilda; Astini, Ricardo A.; Nieto, Fernando; Nieto, José Miguel

    2014-07-01

    A 44 m-thick lacustrine succession of silty-clay banded ochres and subordinated sandstones, and conglomerates (known as the Corral Amarillo Formation) is superbly exposed within the Famatina Belt (Central Andes of Argentina) after deep entrenchment by the present-day Amarillo river due to strong recent uplifting and consequent relative drop in base level. The unusual ochreous-rich succession was produced by natural damming (3.48-3.54 14C kyr BP) of an acid drainage system linked to the alteration cap of polymetallic deposits. Facies of silty-clay ochre (wet season) and banded ochre (dry season) from the paleolacustrine setting are composed of jarosite + goethite and goethite respectively. Geochemically, these layers record high concentrations of Fe2O3 (25-55 wt. %) and trace elements (Cu, Zn, Co, As, and Mo with mean concentrations of 2759; 2467; 109; 375 and 116 ppm, respectively). Their origin is inferred from a comparative analysis with the present-day Amarillo river, which has a pH of ˜3, (SO4)2- concentrations of ˜5000 mg/l, and jarosite as the dominant phase, in the upper catchments. Waters downstream have pH values of 3-4.5, (SO4)2- concentrations of ˜3000-480 mg/l, and schwertmannite as the dominant phase. Thus goethite in the paleolake facies is likely related to schwertmannite transformation by an aging process, whereas jarosite is probably transported from the river but could also be associated with post-depositional formation regulated by variations in grain size and the pore fluid chemistry. The Corral Amarillo Formation offers a Natural model, which may be employed to infer the effect on nature of acid drainage of mineralized areas.

  2. Structural analyses of a rigid pavement overlaying a sub-surface void

    NASA Astrophysics Data System (ADS)

    Adam, Fatih Alperen

    Pavement failures are very hazardous for public safety and serviceability. These failures in pavements are mainly caused by subsurface voids, cracks, and undulation at the slab-base interface. On the other hand, current structural analysis procedures for rigid pavement assume that the slab-base interface is perfectly planar and no imperfections exist in the sub-surface soil. This assumption would be violated if severe erosion were to occur due to inadequate drainage, thermal movements, and/or mechanical loading. Until now, the effect of erosion was only considered in the faulting performance model, but not with regards to transverse cracking at the mid-slab edge. In this research, the bottom up fatigue cracking potential, caused by the combined effects of wheel loading and a localized imperfection in the form of a void below the mid-slab edge, is studied. A robust stress and surface deflection analysis was also conducted to evaluate the influence of a sub-surface void on layer moduli back-calculation. Rehabilitative measures were considered, which included a study on overlay and fill remediation. A series regression of equations was proposed that provides a relationship between void size, layer moduli stiffness, and the overlay thickness required to reduce the stress to its original pre-void level. The effect of the void on 3D pavement crack propagation was also studied under a single axle load. The amplifications to the stress intensity was shown to be high but could be mitigated substantially if stiff material is used to fill the void and impede crack growth. The pavement system was modeled using the commercial finite element modeling program Abaqus RTM. More than 10,000 runs were executed to do the following analysis: stress analysis of subsurface voids, E-moduli back-calculation of base layer, pavement damage calculations of Beaumont, TX, overlay thickness estimations, and mode I crack analysis. The results indicate that the stress and stress intensity are, on

  3. Urban Drainage Modeling and Flood Risk Management

    NASA Astrophysics Data System (ADS)

    Schmitt, Theo G.; Thomas, Martin

    The European research project in the EUREKA framework, RisUrSim (Σ!2255) has been worked out by a project consortium including industrial mathematics and water engineering research institutes, municipal drainage works as well as an insurance company. The overall objective has been the development of a simulation to allow flood risk analysis and cost-effective management for urban drainage systems. In view of the regulatory background of European Standard EN 752, the phenomenon of urban flooding caused by surcharged sewer systems in urban drainage systems is analyzed, leading to the necessity of dual drainage modeling. A detailed dual drainage simulation model is described based upon hydraulic flow routing procedures for surface flow and pipe flow. Special consideration is given to the interaction between surface and sewer flow in order to most accurately compute water levels above ground as a basis for further assessment of possible damage costs. The model application is presented for small case study in terms of data needs, model verification, and first simulation results.

  4. Wound Drainage Culture (For Parents)

    MedlinePlus

    ... Your 1- to 2-Year-Old Wound Drainage Culture KidsHealth > For Parents > Wound Drainage Culture Print A A A What's in this article? ... de heridas What It Is A wound drainage culture is a test to detect germs such as ...

  5. The Serpentinite Subsurface Microbiome

    NASA Astrophysics Data System (ADS)

    Schrenk, M. O.; Nelson, B. Y.; Brazelton, W. J.

    2011-12-01

    Microbial habitats hosted in ultramafic rocks constitute substantial, globally-distributed portions of the subsurface biosphere, occurring both on the continents and beneath the seafloor. The aqueous alteration of ultramafics, in a process known as serpentinization, creates energy rich, high pH conditions, with low concentrations of inorganic carbon which place fundamental constraints upon microbial metabolism and physiology. Despite their importance, very few studies have attempted to directly access and quantify microbial activities and distributions in the serpentinite subsurface microbiome. We have initiated microbiological studies of subsurface seeps and rocks at three separate continental sites of serpentinization in Newfoundland, Italy, and California and compared these results to previous analyses of the Lost City field, near the Mid-Atlantic Ridge. In all cases, microbial cell densities in seep fluids are extremely low, ranging from approximately 100,000 to less than 1,000 cells per milliliter. Culture-independent analyses of 16S rRNA genes revealed low-diversity microbial communities related to Gram-positive Firmicutes and hydrogen-oxidizing bacteria. Interestingly, unlike Lost City, there has been little evidence for significant archaeal populations in the continental subsurface to date. Culturing studies at the sites yielded numerous alkaliphilic isolates on nutrient-rich agar and putative iron-reducing bacteria in anaerobic incubations, many of which are related to known alkaliphilic and subsurface isolates. Finally, metagenomic data reinforce the culturing results, indicating the presence of genes associated with organotrophy, hydrogen oxidation, and iron reduction in seep fluid samples. Our data provide insight into the lifestyles of serpentinite subsurface microbial populations and targets for future quantitative exploration using both biochemical and geochemical approaches.

  6. Role of microbial exopolymeric substances (EPS) on chromium sorption and transport in heterogeneous subsurface soils: II. Binding of Cr(III) in EPS/soil system.

    PubMed

    Kantar, Cetin; Demiray, Hilal; Dogan, Nazime Mercan

    2011-03-01

    Laboratory batch sorption and column experiments were performed to investigate the effects of microbial EPSs isolated from Pseudomonas putida P18, Pseudomonas aeruginosa P16 and Pseudomonas stutzeri P40 on Cr(III) mobility in heterogeneous subsurface soils. Our batch and column results indicate that microbial EPS may have a pronounced effect on Cr(III) sorption and transport behavior depending on system conditions (e.g., pH, type of EPS). While EPS had no effect on Cr(III) sorption at pH<5, it led to a significant decrease in Cr(III) sorption under slightly acidic to alkaline pH range. Column experiments performed at pH 7.9 suggest that, in the presence of EPS, chromium(III) was significantly mobilized relative to non-EPS containing system due to the formation less sorbing and highly soluble Cr-EPS complexes and competition of EPS against Cr for surface sites. A two-site non-electrostatic surface chemical model incorporating a discrete ligand approach for the description of Cr-EPS interactions accurately predicted Cr(III) sorption and transport behavior in the presence of EPS under variable chemical conditions. Our simulations show that an accurate description of Cr(III) transport in the presence of EPS requires incorporation of proton and Cr(III) binding by EPS, EPS binding by soil minerals, Cr(III) binding by soil minerals, and ternary Cr(III)-EPS surface complexes into the transport equations. Although this approach may not accurately describe the actual mechanisms at the molecular level, it can improve our ability to accurately describe the effects of EPS on Cr(III) mobility in subsurface environment relative to the use of distribution coefficients (K(d)).

  7. Terrestrial Subsurface Ecosystem

    SciTech Connect

    Wilkins, Michael J.; Fredrickson, Jim K.

    2015-10-15

    The Earth’s crust is a solid cool layer that overlays the mantle, with a varying thickness of between 30-50 km on continental plates, and 5-10 km on oceanic plates. Continental crust is composed of a variety of igneous, metamorphic, and sedimentary rocks that weather and re-form over geologic cycles lasting millions to billions of years. At the crust surface, these weathered minerals and organic material combine to produce a variety of soils types that provide suitable habitats and niches for abundant microbial diversity (see Chapter 4). Beneath this soil zone is the subsurface. Once thought to be relatively free of microorganisms, recent estimates have calculated that between 1016-1017 g C biomass (2-19% of Earth’s total biomass) may be present in this environment (Whitman et al., 1998;McMahon and Parnell, 2014). Microbial life in the subsurface exists across a wide range of habitats: in pores associated with relatively shallow unconsolidated aquifer sediments to fractures in bedrock formations that are more than a kilometer deep, where extreme lithostatic pressures and temperatures are encountered. While these different environments contain varying physical and chemical conditions, the absence of light is a constant. Despite this, diverse physiologies and metabolisms enable microorganisms to harness energy and carbon for growth in water-filled pore spaces and fractures. Carbon and other element cycles are driven by microbial activity, which has implications for both natural processes and human activities in the subsurface, e.g., bacteria play key roles in both hydrocarbon formation and degradation. Hydrocarbons are a major focus for human utilization of the subsurface, via oil and gas extraction and potential geologic CO2 sequestration. The subsurface is also utilized or being considered for sequestered storage of high-level radioactive waste from nuclear power generation and residual waste from past production of weapons grade nuclear materials. While our

  8. Pore-scale Evolution of Supercritical CO2 within Bentheimer Sandstone during Multiple Drainage-Imbibition Cycles

    NASA Astrophysics Data System (ADS)

    Herring, A. L.; Andersson, L.; Wildenschild, D.

    2014-12-01

    Geologic CO2 sequestration has been proposed as a climate change mitigation strategy to limit emissions of CO2 to the atmosphere from large fossil-fuel burning CO2 point sources; however, there are concerns associated with the long-term stability of a mobile subsurface CO2 plume. The large-scale movement of subsurface supercritical CO2 (scCO2) can be prevented via capillary trapping, wherein scCO2 is immobilized in the subsurface by capillary interactions between the solid surface, resident brine, and scCO2. Capillary trapping occurs in two steps: first, the porous medium undergoes drainage as scCO2 is injected into the system; then, wetting fluid re-enters the medium in an imbibition process, isolating small bubbles of scCO2 in the pore bodies of the medium. There are many empirical models which predict capillary trapping for a single drainage-imbibition cycle; however, in an engineered CO2 sequestration project, it is possible to implement cyclic scCO2-water injections in a water-alternating-gas (WAG) injection scheme in which the system may undergo multiple CO2 injections to potentially increase the trapping efficiency of scCO2. We present experimental results of multiple drainage-imbibition cycles of scCO2 and 1:6 by mass potassium iodide (KI) brine within Bentheimer sandstone. Capillary (differential) pressure and absolute pressures for each phase were continuously measured throughout each flow process, which is a unique feature of our experimental system. Experiments were conducted at a working pressure of 8.3 MPa (1200 PSI) and 40oC, and synchrotron x-ray computed microtomography (x-ray CMT) images were collected of the drainage and imbibition process endpoints at a resolution of 3.19 μm at the Advanced Photon Source at Argonne National Laboratory. The evolution of the connectivity, topology, morphology, and capillary trapping of scCO2 phase is analyzed as a function of capillary pressure, scCO2 saturation, and sample history. Preliminary results suggest

  9. Paleogeography, Paleo-drainage Systems, and Tectonic Reconstructions of Eocene Northern South America Constrained by U-Pb Detrital Zircon Geochronology

    NASA Astrophysics Data System (ADS)

    Xie, X.; Mann, P.; Escalona, A.

    2008-12-01

    Thick, Eocene to Miocene clastic sedimentary basins are widespread across on- and offshore northern South America and have been identified using seismic reflection data in offshore basins of the Leeward Antilles, the Lesser Antilles arc and forearc, and the Barbados accretionary prism. Several 3 to12-km-thick Paleogene depocenters occur in shelf to deep basinal settings along the offshore margins of Venezuela, Trinidad and Tobago, and Barbados. Previous studies proposed that the proto-Orinoco River has been the single fluvial source for these distal, continentally-derived sandstone units along northern Venezuela as part of the early Eocene to Miocene, proto-Maracaibo fluvial-deltaic system that emanated from the northern Andes of western Venezuela and Colombia. Those distal sandstones were displaced eastward with the movement of the Caribbean plate by several hundred kilometers and are now found in basins and islands of the southeastern Caribbean region. We collected nine Eocene age sandstone samples from well cores and outcrops along the northern South America margin, including Lake Maracaibo, Trinidad and Tobago, and Barbados Island. In total, 945 single detrital zircon grains were analyzed using LA-ICP-MS. The objective is to reconstruct the paleogeography, paleo-drainage system, and tectonic history during Eocene time. New data show that the Eocene Misoa Formation of Lake Maracaibo was characterized by a mixture of Precambrian, Paleozoic, and Mesozoic ages matching age provinces from eastern Cordillera and the Guayana Shield, which is consistent with previous proto-Orinoco River model flowing from the western Amazonian region of Colombia and Brazil through the Maracaibo basin into the area of western Falcon basin. However, coeval Eocene samples from Barbados and Trinidad show a much different age population dominated by Precambrian matching the eastern part of the Guyana shield to the south, which suggests that the western onland system and eastern offshore

  10. Structural influence on the evolution of the pre-Eonile drainage system of southern Egypt: Insights from magnetotelluric and gravity data

    NASA Astrophysics Data System (ADS)

    Roden, Jeff; Abdelsalam, Mohamed G.; Atekwana, Estella; El-Qady, Gad; Tarabees, Elhamy Aly

    2011-12-01

    The Wadi Kubbaniya in the Western Desert of Egypt north of the City of Aswan has been interpreted as the downstream continuation of the Wadi Abu Subeira, comprising an ancient W- and NW-flowing river system originating from the Precambrian crystalline rocks of the Red Sea Hills which were uplifted during the Miocene in association with the opening of the Red Sea. This drainage system is thought to have been active before the onset of the N-flowing Egyptian Nile which started ˜6 Ma with the Eonile phase; an event that resulted in carving of ˜1000 km long canyon (the Eonile canyon) extending from the Mediterranean Sea in the north to Aswan in the south due to the Messinian Salinity Crisis. This study utilizes geophysical data to examine the role of regional tectonics and local structures in controlling the evolution of the pre-Eonile drainage system. Magnetotelluric (MT) and gravity surveys were conducted along two ˜5 km-long profiles across the NW-trending Wadi Kubbaniya. Two-dimensional (2D) inversion of MT data and gravity models indicate the Wadi Kubbaniya is filled with loosely-consolidated sandstone and conglomerate that extend to a depth of ˜150-200 m into Cretaceous sandstone formations which overlie Precambrian crystalline rocks. These results were evaluated in terms of two end-member models; an incision model in which the 150-200 m thick sedimentary rocks were considered as being deposited within an incised valley that was carved into bedrock, or a structural model in which the sedimentary rocks are considered as filling a NW-trending graben controlled by normal faults that deform the Cretaceous sandstone formations and the underlying Precambrian crystalline rocks. Geological observations as well as supporting seismic data favor the interpretation that the Wadi Kubbaniya is a NW-trending graben similar to other extensional structures found 400 km northwest along-strike of Wadi Kubbaniya. These structures are impressively parallel to the western

  11. Retrofitting for watershed drainage

    SciTech Connect

    Bennett, D.B. ); Heaney, J.P. )

    1991-09-01

    Over the past 8 years, degradation in Florida's Indian River Lagoon has taken the form of fish kills, reduced viable recreational and commercial fisheries, and loss of seagrass beds. Stormwater drainage practices in the watershed have been identified as the primary culprit in the slow demise of the lagoon. Specific drainage problems include an increased volume of freshwater runoff to the estuarine receiving water and deposition of organic sediments, reduced water clarity because of increased discharge of suspended solids and tea colored' groundwater - a result of drainage-canal-induced land dewatering, and eutrophication caused by nutrient loadings. In addition, poor flushing in lagoon segments makes runoff impacts even more damaging to the ecosystem. Recently, the lagoon has received national, regional, state, and local attention over its degradation and citizens' action and multi-agency efforts to restore it. To mitigate damage to the Indian River lagoon, agencies are considering alternatives such as retrofitting to reduce pollutant loads and implementing a more comprehensive watershed approach to stormwater management instead of individual controls on new development currently widely practiced. A comprehensive, long-term watershed control approach avoids unnecessary construction expenses, encourages cost-effective tradeoffs based on specific objectives, facilities performance monitoring, and accounts for cumulative impacts of continued growth in the watershed.

  12. Drainage in a rising foam.

    PubMed

    Yazhgur, Pavel; Rio, Emmanuelle; Rouyer, Florence; Pigeonneau, Franck; Salonen, Anniina

    2016-01-21

    Rising foams created by continuously blowing gas into a surfactant solution are widely used in many technical processes, such as flotation. The prediction of the liquid fraction profile in such flowing foams is of particular importance since this parameter controls the stability and the rheology of the final product. Using drift flux analysis and recently developed semi-empirical expressions for foam permeability and osmotic pressure, we build a model predicting the liquid fraction profile as a function of height. The theoretical profiles are very different if the interfaces are considered as mobile or rigid, but all of our experimental profiles are described by the model with mobile interfaces. Even the systems with dodecanol are well known to behave as rigid in forced drainage experiments. This is because in rising foams the liquid fraction profile is fixed by the flux at the bottom of the foam. Here the foam is wet with higher permeability and the interfaces are not in equilibrium. These results demonstrate once again that it is not only the surfactant system that controls the mobility of the interface, but also the hydrodynamic problem under consideration. For example liquid flow through the foam during generation or in forced drainage is intrinsically different.

  13. Fluid Drainage from Porous Reservoirs

    NASA Astrophysics Data System (ADS)

    Zheng, Zhong; Soh, Beatrice; Huppert, Herbert; Stone, Howard; Stone Group Team

    2012-11-01

    We report theoretical and experimental studies to describe buoyancy-driven fluid drainage from a porous medium. We first study homogeneous porous systems. To investigate the influence of heterogeneities, we consider the case where the permeability varies transverse to the flow direction, exemplified by a V-shaped Hele-Shaw cell. Finally, we analyze a model where both the permeability and the porosity vary transverse to the flow direction. In each case, a self-similar solution for the shape of the gravity current is found and a power-law behavior in time is derived for the mass remaining in the system. Laboratory experiments are conducted in homogeneous and V-shaped Hele-Shaw cells, and the measured profile shapes and the mass remaining in the cells agree well with our model predictions. Our study provides new insights into drainage processes such as may occur in a variety of natural and industrial activities including the geological storage of carbon dioxide. This work is supported by a grant from Carbon Mitigation Initiative at Princeton University.

  14. Reducing nitrogen loss with managed drainage and polymer-coated urea.

    PubMed

    Nash, Patrick; Nelson, Kelly; Motavalli, Peter

    2015-01-01

    Continuous corn ( L.) production during dry years combined with high N fertilizer rates can have a high potential for NO-N loss through tile drainage water. Claypan soils can further increase the potential for NO-N loss through tile drainage water due to the claypan layer that restricts N leaching below the tile drains. The objective of this 4-yr study was to determine whether use of managed subsurface drainage (MD) in combination with a controlled-release N fertilizer could reduce the annual amount of NO-N loss through tile drainage water compared with free subsurface tile drainage (FD) with a noncoated urea application. Due to dry conditions over the summer and fall months, MD reduced the annual amount of water drained by at least 73% compared with FD in two of the four crop years. Low N loss and reduced corn N uptake possibly resulted in carry-over N and high soil N concentrations throughout the study, which may have limited the effect of N fertilizer source on annual NO-N loss in the tile drainage water. Use of MD reduced annual NO-N loss in the tile drainage water by 78 to 85% in two of the four years. High NO-N loss reduction with MD compared with FD was largely due to dry growing season conditions in combination with wet conditions over the noncropping period.

  15. The sulfur system in anoxic subsurface brines and its implication in brine evolutionary pathways: the Ca-chloride brines in the Dead Sea area

    NASA Astrophysics Data System (ADS)

    Gavrieli, Ittai; Yechieli, Yoseph; Halicz, Ludwik; Spiro, Baruch; Bein, Amos; Efron, Dov

    2001-03-01

    boreholes and are saturated to oversaturated with respect to gypsum. Calculations based on their ammonium content suggest that both groups of brine require apparent unreasonably high oversaturations with respect to gypsum prior to the onset of the reduction. This implies that the groundwater systems were open with respect to sulfate, and that the sulfate reservoir was replenished continuously or intermittently during the BSR. The DSIF-Tappuah brines continue to dissolve gypsum during their BSR. The dissolving sulfate is derived from relatively isotopically enriched gypsums (δ 34S SO4>20‰), such as found in the Lisan Formation. These brines approach the steady-state isotopic composition (δ 34S ss) dictated by the combination of the δ 34S of the dissolving gypsum and the fractionation factor accompanying BSR. The sulfur isotopic composition of the Qedem-Shalem brines implies that most of their ammonium content is derived from an earlier phase of BSR and that the last phase of BSR takes place during the brines' rapid ascent to the surface. Prior to this stage they evolved through either: (1) dissolution of gypsum with δ 34S SO4≤20‰ which occurred after the main BSR in the subsurface; (2) a previous phase in which the brines were part of a lake and later percolated to the subsurface. As such, their isotopic composition and ammonium content were determined by the combined effect of freshwater sulfate input to the lake and BSR in the stratified lake.

  16. Inventory of drainage wells and potential sources of contaminants to drainage-well inflow in Southwest Orlando, Orange County, Florida

    USGS Publications Warehouse

    Taylor, George Fred

    1993-01-01

    Potential sources of contaminants that could pose a threat to drainage-well inflow and to water in the Floridan aquifer system in southwest Orlando, Florida, were studied between October and December 1990. Drainage wells and public-supply wells were inventoried in a 14-square-mile area, and available data on land use and activities within each drainage well basin were tabulated. Three public-supply wells (tapping the Lower Floridan aquifer) and 38 drainage wells (open to the Upper Floridan aquifer) were located in 17 drainage basins within the study area. The primary sources of drainage-well inflow are lake overflow, street runoff, seepage from the surficial aquifer system, and process-wastewater disposal. Drainage-well inflow from a variety of ares, including resi- dential, commercial, undeveloped, paved, and industrial areas, are potential sources of con- taminants. The four general types of possible contaminants to drainage-well inflow are inorganic chemicals, organic compounds, turbidity, and microbiological contaminants. Potential contami- nant sources include plant nurseries, citrus groves, parking lots, plating companies, auto- motive repair shops, and most commonly, lake- overflow water. Drainage wells provide a pathway for contaminants to enter the Upper Floridan aquifer and there is a potential for contaminants to move downward from the Upper Floridan to the Lower Floridan aquifer.

  17. Utilization of subsurface microbial electrochemical systems to elucidate the mechanisms of competition between methanogenesis and microbial iron(III)/humic acid reduction in Arctic peat soils

    NASA Astrophysics Data System (ADS)

    Friedman, E. S.; Miller, K.; Lipson, D.; Angenent, L. T.

    2012-12-01

    High-latitude peat soils are a major carbon reservoir, and there is growing concern that previously dormant carbon from this reservoir could be released to the atmosphere as a result of continued climate change. Microbial processes, such as methanogenesis and carbon dioxide production via iron(III) or humic acid reduction, are at the heart of the carbon cycle in Arctic peat soils [1]. A deeper understanding of the factors governing microbial dominance in these soils is crucial for predicting the effects of continued climate change. In previous years, we have demonstrated the viability of a potentiostatically-controlled subsurface microbial electrochemical system-based biosensor that measures microbial respiration via exocellular electron transfer [2]. This system utilizes a graphite working electrode poised at 0.1 V NHE to mimic ferric iron and humic acid compounds. Microbes that would normally utilize these compounds as electron acceptors donate electrons to the electrode instead. The resulting current is a measure of microbial respiration with the electrode and is recorded with respect to time. Here, we examine the mechanistic relationship between methanogenesis and iron(III)- or humic acid-reduction by using these same microbial-three electrode systems to provide an inexhaustible source of alternate electron acceptor to microbes in these soils. Chamber-based carbon dioxide and methane fluxes were measured from soil collars with and without microbial three-electrode systems over a period of four weeks. In addition, in some collars we simulated increased fermentation by applying acetate treatments to understand possible effects of continued climate change on microbial processes in these carbon-rich soils. The results from this work aim to increase our fundamental understanding of competition between electron acceptors, and will provide valuable data for climate modeling scenarios. 1. Lipson, D.A., et al., Reduction of iron (III) and humic substances plays a major

  18. 33 CFR 157.134 - Cargo tank drainage.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.134 Cargo tank drainage. Each cargo tank must be designed for longitudinal and transverse drainage of crude oil to...

  19. 33 CFR 157.134 - Cargo tank drainage.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.134 Cargo tank drainage. Each cargo tank must be designed for longitudinal and transverse drainage of crude oil to...

  20. 33 CFR 157.134 - Cargo tank drainage.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.134 Cargo tank drainage. Each cargo tank must be designed for longitudinal and transverse drainage of crude oil to...

  1. 33 CFR 157.134 - Cargo tank drainage.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157.134 Cargo tank drainage. Each cargo tank must be designed for longitudinal and transverse drainage of crude oil to...

  2. Nutrient mitigation efficiency in agricultural drainage ditches: An influence of landscape properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage systems are integral parts of the agricultural landscapes and have the ability to intercept nutrient loading from runoff to surface water. This study investigated nutrient removal efficiency within replicated experimental conventional and controlled (with weirs) agricultural drainage ditche...

  3. AMELIORATION OF ACID MINE DRAINAGE USING REACTIVE MIXTURES IN PERMEABLE REACTIVE BARRIERS

    EPA Science Inventory

    The generation and release of acidic drainage from mine wastes is an environmental problem of international scale. The use of zero-valent iron and/or iron mixtures in subsurface Permeable Reactive Barriers (PRB) presents a possible passive alternative for remediating acidic grou...

  4. Use of industrial byproducts to filter PO43- and pesticides in golf green drainage water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Golf courses are vulnerable to phosphate (PO43-) and pesticide loss by infiltration because of the sandy, porous grass rooting media used and presence of subsurface tile drainage. In this study, a blend of industrial byproducts, including granulated blast furnace slag (GBFS), cement kiln dust (CKD),...

  5. Performance of dentrification beds for removing nitrate from drainage water at cold temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transport of soluble nitrogen and phosphorus to water bodies has been a concern for many years due to human health issues, and is a major contributor to the formation of oxygen deficiency in aquatic ecosystems. Agricultural subsurface drainage is one pathway for transport of excess nutrients to surf...

  6. Land Application of Wastes: An Educational Program. Drainage for Land Application Sites - Module 21, Objectives, and Script.

    ERIC Educational Resources Information Center

    Clarkson, W. W.; And Others

    Drainage for land treatment sites must be evaluated with respect to the purpose the system is meant to achieve. Off-site drainage controls the flow of storm runoff onto the site or groundwater incursion into the soil within the site. On-site drainage is employed for a variety of reasons. These two areas of drainage control must be designed as a…

  7. Reduction of blood loss with the use of a new combined intra-operative and post-operative autologous blood transfusion system compared with no drainage in primary total hip replacement.

    PubMed

    Horstmann, W G; Swierstra, M J; Ohanis, D; Castelein, R M; Kollen, B J; Verheyen, C C P M

    2013-05-01

    Autologous retransfusion and no-drainage are both blood-saving measures in total hip replacement (THR). A new combined intra- and post-operative autotransfusion filter system has been developed especially for primary THR, and we conducted a randomised controlled blinded study comparing this with no-drainage. A total of 204 THR patients were randomised to autologous blood transfusion (ABT) (n = 102) or no-drainage (n = 102). In the ABT group, a mean of 488 ml (sd 252) of blood was retransfused. The mean lowest post-operative haemoglobin level during the hospital stay was higher in the autotransfusion group (10.6 g/dl (7.8 to 13.9) vs 10.2 g/dl (7.5 to 13.3); p = 0.01). The mean haemoglobin levels for the ABT and no-drainage groups were not significantly different on the first day (11.3 g/dl (7.8 to 13.9) vs 11.0 g/dl (8.1 to 13.4); p = 0.07), the second day (11.1 g/dl (8.2 to 13.8) vs 10.8 g/dl (7.5 to 13.3); p = 0.09) or the third day (10.8 g/dl (8.0 to 13.0) vs 10.6 g/dl (7.5 to 14.1); p = 0.15). The mean total peri-operative net blood loss was 1464 ml (sd 505) in the ABT group and 1654 ml (sd 553) in the no-drainage group (p = 0.01). Homologous blood transfusions were needed in four patients (3.9%) in the ABT group and nine (8.8%) in the no-drainage group (p = 0.15). No statistically significant difference in adverse events was found between the groups. The use of a new intra- and post-operative autologous blood transfusion filter system results in less total blood loss and a smaller maximum decrease in haemoglobin levels than no-drainage following primary THR.

  8. Removal of metal from acid mine drainage using a hybrid system including a pipes inserted microalgae reactor.

    PubMed

    Park, Young-Tae; Lee, Hongkyun; Yun, Hyun-Shik; Song, Kyung-Guen; Yeom, Sung-Ho; Choi, Jaeyoung

    2013-12-01

    In this study, the microalgae culture system to combined active treatment system and pipe inserted microalgae reactor (PIMR) was investigated. After pretreated AMD in active treatment system, the effluent load to PIMR in order to Nephroselmis sp. KGE 8 culture. In experiment, effect of iron on growth and lipid accumulation in microalgae were inspected. The 2nd pretreatment effluent was economic feasibility of microalgae culture and lipid accumulation. The growth kinetics of the microalgae are modeled using logistic growth model and the model is primarily parameterized from data obtained through an experimental study where PIMR were dosed with BBM, BBM added 10 mg L(-1) iron and 2nd pretreatment effluent. Moreover, the continuous of microalgae culture in PIMR can be available. Overall, this study indicated that the use of pretreated AMD is a viable method for culture microalgae and lipid accumulation.

  9. From highly polluted Zn-rich acid mine drainage to non-metallic waters: implementation of a multi-step alkaline passive treatment system to remediate metal pollution.

    PubMed

    Macías, Francisco; Caraballo, Manuel A; Rötting, Tobias S; Pérez-López, Rafael; Nieto, José Miguel; Ayora, Carlos

    2012-09-01

    Complete metal removal from highly-polluted acid mine drainage was attained by the use of a pilot multi-step passive remediation system. The remediation strategy employed can conceptually be subdivided into a first section where the complete trivalent metal removal was achieved by the employment of a previously tested limestone-based passive remediation technology followed by the use of a novel reactive substrate (caustic magnesia powder dispersed in a wood shavings matrix) obtaining a total divalent metal precipitation. This MgO-step was capable to abate high concentrations of Zn together with Mn, Cd, Co and Ni below the recommended limits for drinking waters. A reactive transport model anticipates that 1 m(3) of MgO-DAS (1 m thick × 1 m(2) section) would be able to treat a flow of 0.5 L/min of a highly acidic water (total acidity of 788 mg/L CaCO(3)) for more than 3 years.

  10. Ichthyofauna of the Kubo, Tochikura, and Ichinono river systems (Kitakami River drainage, northern Japan), with a comparison of predicted and surveyed species richness

    PubMed Central

    Nakae, Masanori; Senou, Hiroshi

    2014-01-01

    Abstract The potential fish species pool of the Kubo, Tochikura, and Ichinono river systems (tributaries of the Iwai River, Kitakami River drainage), Iwate Prefecture, northern Japan, was compared with the observed ichthyofauna by using historical records and new field surveys. Based on the literature survey, the potential species pool comprised 24 species/subspecies but only 20, including 7 non-native taxa, were recorded during the fieldwork. The absence during the survey of 11 species/subspecies from the potential species pool suggested either that sampling effort was insufficient, or that accurate determination of the potential species pool was hindered by lack of biogeographic data and ecological data related to the habitat use of the species. With respect to freshwater fish conservation in the area, Lethenteron reissneri, Carassius auratus buergeri, Pseudorasbora pumila, Tachysurus tokiensis, Oryzias latipes, and Cottus nozawae are regarded as priority species, and Cyprinus rubrofuscus, Pseudorasbora parva, and Micropterus salmoides as targets for removal. PMID:25425932

  11. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    SciTech Connect

    Rozemeijer, J. C.; Visser, A.; Borren, W.; Winegram, M.; van der Velde, Y.; Klein, J.; Broers, H. P.

    2016-01-19

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates and the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007–2008) and after (2009–2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. Furthermore, this may be counteracted by the higher groundwater levels and the larger contribution of N- and

  12. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    NASA Astrophysics Data System (ADS)

    Rozemeijer, J. C.; Visser, A.; Borren, W.; Winegram, M.; van der Velde, Y.; Klein, J.; Broers, H. P.

    2016-01-01

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates and the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007-2008) and after (2009-2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. However, this may be counteracted by the higher groundwater levels and the larger contribution of N- and P

  13. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    DOE PAGES

    Rozemeijer, J. C.; Visser, A.; Borren, W.; ...

    2016-01-19

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates andmore » the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007–2008) and after (2009–2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. Furthermore, this may be counteracted by the higher groundwater levels and the larger contribution

  14. 24 CFR 3285.203 - Site Drainage.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Purpose. Drainage must be provided to direct surface water away from the home to protect against erosion of foundation supports and to prevent water build-up under the home, as shown in Figure to § 3285.203... tile and automatic sump pump system, must be provided to remove any water that may collect under...

  15. 24 CFR 3285.203 - Site Drainage.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Purpose. Drainage must be provided to direct surface water away from the home to protect against erosion of foundation supports and to prevent water build-up under the home, as shown in Figure to § 3285.203... tile and automatic sump pump system, must be provided to remove any water that may collect under...

  16. [Artificial drainage devices--history, indications].

    PubMed

    Barac, Ileana Ramona; Pop, Monica

    2012-01-01

    Glaucoma is a degenerative optic neuropathy progressive, multifactorial, which can lead to blindness. Blindness in patients with glaucoma is defined as visual field reduction below 10 degrees. Artificial drainage systems are a solution for refractory to medication, laser treatment or conventional surgery. Used by over 100 years, improved with good surgical technique and careful patient follow-up surgery, postoperative results are satisfactory.

  17. Development and evaluation of 50-mer oligonucleotide arrays for detecting microbial populations in Acid Mine Drainages and bioleaching systems.

    PubMed

    Yin, Huaqun; Cao, Linhui; Qiu, Guanzhou; Wang, Dianzuo; Kellogg, Laurie; Zhou, Jizhong; Dai, Zhimin; Liu, Xueduan

    2007-07-01

    To effectively monitor microbial populations in acidic environments and bioleaching systems, a comprehensive 50-mer-based oligonucleotide microarray was developed based on most of the known genes associated with the acidophiles. This array contained 1,072 probes in which there were 571 related to 16S rRNA and 501 related to functional genes. The functional genes in the microarray were involved in carbon metabolism (158), nitrogen metabolism (72), sulfur metabolism (39), iron metabolism (68), DNA replication and repair (97), metal-resistance (27), membrane-relate gene (16), transposon (13) and IST sequence (11). Based on the results of microarray hybridizations, specificity tests with representative pure cultures indicated that the designed probes on the arrays appeared to be specific to their corresponding target genes. The detection limit was 5 ng of genomic DNA in the absence of background DNA. Strong linear relationships between the signal intensity and the target DNA were observed (r(2) approximately 0.98). Application of this type of the microarray to analyze the acidic environments and bioleaching systems demonstrated that the developed microarray appeared to be useful for profiling differences in microbial community structures of acidic environments and bioleaching systems. Our results indicate that this technology has potential as a specific, sensitive, and quantitative tool in revealing a comprehensive picture of the compositions of genes related with acidophilic microorganism and the microbial community in acidic environments and bioleaching systems, although more work is needed to improve.

  18. Wave-Based Subsurface Guide Star

    SciTech Connect

    Lehman, S K

    2011-07-26

    Astronomical or optical guide stars are either natural or artificial point sources located above the Earth's atmosphere. When imaged from ground-based telescopes, they are distorted by atmospheric effects. Knowing the guide star is a point source, the atmospheric distortions may be estimated and, deconvolved or mitigated in subsequent imagery. Extending the guide star concept to wave-based measurement systems to include acoustic, seismo-acoustic, ultrasonic, and radar, a strong artificial scatterer (either acoustic or electromagnetic) may be buried or inserted, or a pre-existing or natural sub-surface point scatterer may be identified, imaged, and used as a guide star to determine properties of the sub-surface volume. That is, a data collection is performed on the guide star and the sub-surface environment reconstructed or imaged using an optimizer assuming the guide star is a point scatterer. The optimization parameters are the transceiver height and bulk sub-surface background refractive index. Once identified, the refractive index may be used in subsequent reconstructions of sub-surface measurements. The wave-base guide star description presented in this document is for a multimonostatic ground penetrating radar (GPR) but is applicable to acoustic, seismo-acoustic, and ultrasonic measurement systems operating in multimonostatic, multistatic, multibistatic, etc., modes.

  19. Lymph drainage in pregnant women.

    PubMed

    Cataldo Oportus, Sylvia; de Paiva Rodrigues, Lilian; Pereira de Godoy, José Maria; Guerreiro Godoy, Maria de Fátima

    2013-01-01

    Aim. The aim of this study was to evaluate the efficacy of lymph drainage to reduce edema of pregnant women. Method. Pregnant women (30 limbs) from the Obstetrics Outpatient Clinic of the Medical School of Santa Casa in São Paulo in the period December 2009 to May 2010 were enrolled in this quantitative, prospective study. The patients, in the 5th to 8th months of gestation, were submitted to one hour of manual lymph drainage of the legs. The volume of the legs was measured by water displacement volumetry before and after one hour of drainage using the Godoy & Godoy manual lymph drainage technique. The paired t-test was used for statistical analysis with an alpha error of 5% being considered significant. Results. Manual lymph drainage significantly reduced swelling of the legs of pregnant women during the day (P = 0.04). Conclusion. Manual lymph drainage helps to reduce limb size during the day of pregnant women.

  20. Subsurface contaminants focus area

    SciTech Connect

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  1. Corn stover harvest increases herbicide movement to subsurface drains: RZWQM simulations

    USGS Publications Warehouse

    Shipitalo, Martin J.; Malone, Robert W.; Ma, Liwang; Nolan, Bernard T.; Kanwar, Rameshwar S.; Shaner, Dale L.; Pederson, Carl H.

    2016-01-01

    BACKGROUND Crop residue removal for bioenergy production can alter soil hydrologic properties and the movement of agrochemicals to subsurface drains. The Root Zone Water Quality Model (RZWQM), previously calibrated using measured flow and atrazine concentrations in drainage from a 0.4 ha chisel-tilled plot, was used to investigate effects of 50 and 100% corn (Zea mays L.) stover harvest and the accompanying reductions in soil crust hydraulic conductivity and total macroporosity on transport of atrazine, metolachlor, and metolachlor oxanilic acid (OXA). RESULTS The model accurately simulated field-measured metolachlor transport in drainage. A 3-yr simulation indicated that 50% residue removal decreased subsurface drainage by 31% and increased atrazine and metolachlor transport in drainage 4 to 5-fold when surface crust conductivity and macroporosity were reduced by 25%. Based on its measured sorption coefficient, ~ 2-fold reductions in OXA losses were simulated with residue removal. CONCLUSION RZWQM indicated that if corn stover harvest reduces crust conductivity and soil macroporosity, losses of atrazine and metolachlor in subsurface drainage will increase due to reduced sorption related to more water moving through fewer macropores. Losses of the metolachlor degradation product OXA will decrease due to the more rapid movement of the parent compound into the soil.

  2. Computationally efficient and flexible modular modelling approach for river and urban drainage systems based on surrogate conceptual models

    NASA Astrophysics Data System (ADS)

    Wolfs, Vincent; Willems, Patrick

    2015-04-01

    Water managers rely increasingly on mathematical simulation models that represent individual parts of the water system, such as the river, sewer system or waste water treatment plant. The current evolution towards integral water management requires the integration of these distinct components, leading to an increased model scale and scope. Besides this growing model complexity, certain applications gained interest and importance, such as uncertainty and sensitivity analyses, auto-calibration of models and real time control. All these applications share the need for models with a very limited calculation time, either for performing a large number of simulations, or a long term simulation followed by a statistical post-processing of the results. The use of the commonly applied detailed models that solve (part of) the de Saint-Venant equations is infeasible for these applications or such integrated modelling due to several reasons, of which a too long simulation time and the inability to couple submodels made in different software environments are the main ones. Instead, practitioners must use simplified models for these purposes. These models are characterized by empirical relationships and sacrifice model detail and accuracy for increased computational efficiency. The presented research discusses the development of a flexible integral modelling platform that complies with the following three key requirements: (1) Include a modelling approach for water quantity predictions for rivers, floodplains, sewer systems and rainfall runoff routing that require a minimal calculation time; (2) A fast and semi-automatic model configuration, thereby making maximum use of data of existing detailed models and measurements; (3) Have a calculation scheme based on open source code to allow for future extensions or the coupling with other models. First, a novel and flexible modular modelling approach based on the storage cell concept was developed. This approach divides each

  3. Reconnecting tile drainage to riparian buffer hydrology for enhanced nitrate removal.

    PubMed

    Jaynes, D B; Isenhart, T M

    2014-03-01

    Riparian buffers are a proven practice for removing NO from overland flow and shallow groundwater. However, in landscapes with artificial subsurface (tile) drainage, most of the subsurface flow leaving fields is passed through the buffers in drainage pipes, leaving little opportunity for NO removal. We investigated the feasibility of re-routing a fraction of field tile drainage as subsurface flow through a riparian buffer for increasing NO removal. We intercepted an existing field tile outlet draining a 10.1-ha area of a row-cropped field in central Iowa and re-routed a fraction of the discharge as subsurface flow along 335 m of an existing riparian buffer. Tile drainage from the field was infiltrated through a perforated pipe installed 75 cm below the surface by maintaining a constant head in the pipe at a control box installed in-line with the existing field outlet. During 2 yr, >18,000 m (55%) of the total flow from the tile outlet was redirected as infiltration within the riparian buffer. The redirected water seeped through the 60-m-wide buffer, raising the water table approximately 35 cm. The redirected tile flow contained 228 kg of NO. On the basis of the strong decrease in NO concentrations within the shallow groundwater across the buffer, we hypothesize that the NO did not enter the stream but was removed within the buffer by plant uptake, microbial immobilization, or denitrification. Redirecting tile drainage as subsurface flow through a riparian buffer increased its NO removal benefit and is a promising management practice to improve surface water quality within tile-drained landscapes.

  4. Relating sulfide mineral zonation and trace element chemistry to subsurface processes in the Reykjanes geothermal system, Iceland

    NASA Astrophysics Data System (ADS)

    Libbey, R. B.; Williams-Jones, A. E.

    2016-01-01

    The nature and distribution of sulfide minerals and their trace element chemistry in the seawater-dominated Reykjanes geothermal system was determined through the study of cuttings and core from wells that intersect different regions of the hydrothermal cell, from the near surface to depths of > 3000 m. The observed sulfide mineral zonation and trace element enrichment correlate well with the present-day thermal structure of the system. Isocubanite and pyrrhotite are confined to the deep, low permeability regions, whereas an assemblage of chalcopyrite and pyrite predominates in the main convective upflow path. The presence of marcasite in the uppermost regions of the system reflects weakly acidic conditions (pH < 5) marginal to the upflow, where outflow and downward percolating fluids have dissolved deeply exsolved CO2. The presence of "chalcopyrite disease" in sphalerite may be an indication that the system is experiencing a heating trend, following the logic of "zone-refining" in volcanogenic massive sulfide systems. Sulfide sulfur at all analyzed depths in the Reykjanes geothermal system was derived from a mixture of basaltic and reduced seawater sources. Petrographic evidence suggests that seawater-derived hydrothermal fluids have altered primary igneous sulfides in the host rocks, a process that has been proposed as a major control of aqueous sulfide production in mid-ocean ridge environments. Calculations show that igneous sulfides in the host basalts likely account for less than 5% of the total available ore metal budget in the system, however, their contribution to fluid metal budgets is probably significant because of their relatively high solubility. The processes documented by this study are likely analogous to those operating in the feeder and deep reaction zones of mid-ocean ridge seafloor hydrothermal systems. The results show that sulfide mineral zonation and trace element chemistry vary as a function of physicochemical parameters that are relevant

  5. Laser-induced fluorescence imaging of subsurface tissue structures with a volume holographic spatial-spectral imaging system.

    PubMed

    Luo, Yuan; Gelsinger-Austin, Paul J; Watson, Jonathan M; Barbastathis, George; Barton, Jennifer K; Kostuk, Raymond K

    2008-09-15

    A three-dimensional imaging system incorporating multiplexed holographic gratings to visualize fluorescence tissue structures is presented. Holographic gratings formed in volume recording materials such as a phenanthrenquinone poly(methyl methacrylate) photopolymer have narrowband angular and spectral transmittance filtering properties that enable obtaining spatial-spectral information within an object. We demonstrate this imaging system's ability to obtain multiple depth-resolved fluorescence images simultaneously.

  6. Use of a novel covered self-expandable metal stent with an anti-migration system for endoscopic ultrasound-guided drainage of a pseudocyst

    PubMed Central

    Téllez-Ávila, Félix Ignacio; Villalobos-Garita, Álvaro; Ramírez-Luna, Miguel Ángel

    2013-01-01

    The development of pseudocysts in patients with chronic pancreatitis has been reported in 23%-60% of cases and drainage is indicated when they become symptomatic. Endoscopic ultrasound-guided drainage with the placement of plastic or metallic stents to create a cystogastric anastomosis has been shown to be a reliable and efficacious maneuver. Metallic stent use appears to be a safe and effective alternative that shortens the length of time of the procedure and maintains a greater diameter in the cystogastric communication. However, important migration rates have been reported. The use of new metallic stents that are specially designed to prevent migration represents a promising development in the treatment of these group of patients that appears to be safe and effective for pseudocyst drainage and could importantly reduce migration rates, while at the same time having the advantage of a single step procedure and a larger fistula diameter in the endoscopic cystogastric anastomosis. PMID:23772268

  7. Arctic-HYCOS: a Large Sample observing system for estimating freshwater fluxes in the drainage basin of the Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Pietroniro, Al; Korhonen, Johanna; Looser, Ulrich; Hardardóttir, Jórunn; Johnsrud, Morten; Vuglinsky, Valery; Gustafsson, David; Lins, Harry F.; Conaway, Jeffrey S.; Lammers, Richard; Stewart, Bruce; Abrate, Tommaso; Pilon, Paul; Sighomnou, Daniel; Arheimer, Berit

    2015-04-01

    The Arctic region is an important regulating component of the global climate system, and is also experiencing a considerable change during recent decades. More than 10% of world's river-runoff flows to the Arctic Ocean and there is evidence of changes in its fresh-water balance. However, about 30% of the Arctic basin is still ungauged, with differing monitoring practices and data availability from the countries in the region. A consistent system for monitoring and sharing of hydrological information throughout the Arctic region is thus of highest interest for further studies and monitoring of the freshwater flux to the Arctic Ocean. The purpose of the Arctic-HYCOS project is to allow for collection and sharing of hydrological data. Preliminary 616 stations were identified with long-term daily discharge data available, and around 250 of these already provide online available data in near real time. This large sample will be used in the following scientific analysis: 1) to evaluate freshwater flux to the Arctic Ocean and Seas, 2) to monitor changes and enhance understanding of the hydrological regime and 3) to estimate flows in ungauged regions and develop models for enhanced hydrological prediction in the Arctic region. The project is intended as a component of the WMO (World Meteorological Organization) WHYCOS (World Hydrological Cycle Observing System) initiative, covering the area of the expansive transnational Arctic basin with participation from Canada, Denmark, Finland, Iceland, Norway, Russian Federation, Sweden and United States of America. The overall objective is to regularly collect, manage and share high quality data from a defined basic network of hydrological stations in the Arctic basin. The project focus on collecting data on discharge and possibly sediment transport and temperature. Data should be provisional in near-real time if available, whereas time-series of historical data should be provided once quality assurance has been completed. The

  8. Comparison of Identification Systems for Classification of Bacteria Isolated from Water and Endolithic Habitats within the Deep Subsurface

    PubMed Central

    Amy, P. S.; Haldeman, D. L.; Ringelberg, D.; Hall, D. H.; Russell, C.

    1992-01-01

    One water and three rock samples were taken from a mined tunnel system, U12n, in Rainier Mesa at the Nevada Test Site. Endolithic microorganisms were cultured from ashfall tuff, which was crushed and made into slurries with a formulation of artificial pore water, on R2A agar plates. Microbial counts ranged from 102 to 104 viable cells per g (dry weight) of rock sampled. The cultured water sample yielded 102 viable cells per ml. Many of the isolates were very small (<1 μm) when viewed in the rock matrix and remained small even when cultured. Most were gram-negative rods. Individual isolates were profiled by API-NFT strip number, antibiotic and metal resistance patterns, and colony and cellular morphologies. Three identification systems, API-NFT strips, BIOLOG, and MIDI, were compared. Each system identified only a small percentage of the total isolates, and in only seven cases were the isolates identified the same way by more than one system. The same genus was identified in three of these cases, but different species were indicated. The genus Pseudomonas was the most commonly identified. The isolate profiles and the three identification systems demonstrated that water isolates were considerably different from endolithic isolates. PMID:16348791

  9. Subsurface intake systems: Green choice for improving feed water quality at SWRO desalination plants, Jeddah, Saudi Arabia.

    PubMed

    Dehwah, Abdullah H A; Missimer, Thomas M

    2016-01-01

    An investigation of three seawater reverse osmosis facilities located along the shoreline of the Red Sea of Saudi Arabia that use well intake systems showed that the pumping-induced flow of raw seawater through a coastal aquifer significantly improves feed water quality. A comparison between the surface seawater and the discharge from the wells shows that turbidity, algae, bacteria, total organic carbon, most fractions of natural organic matter (NOM), and particulate and colloidal transparent exopolymer particles (TEP) have significant reductions in concentration. Nearly all of the algae, up to 99% of the bacteria, between 84 and 100% of the biopolymer fraction of NOM, and a high percentage of the TEP were removed during transport. The data suggest that the flowpath length and hydraulic retention time in the aquifer play the most important roles in removal of the organic matter. Since the collective concentrations of bacteria, biopolymers, and TEP in the intake seawater play important roles in the biofouling of SWRO membranes, the observed reductions suggest that the desalination facilities that use well intakes systems will have a potentially lower fouling rate compared to open-ocean intake systems. Furthermore, well intake system intakes also reduce the need for chemical usage during complex pretreatment systems required for operation of SWRO facilities using open-ocean intakes and reduce environmental impacts.

  10. Stable and Variable Parts of Microbial Community in Siberian Deep Subsurface Thermal Aquifer System Revealed in a Long-Term Monitoring Study

    PubMed Central

    Frank, Yulia A.; Kadnikov, Vitaly V.; Gavrilov, Sergey N.; Banks, David; Gerasimchuk, Anna L.; Podosokorskaya, Olga A.; Merkel, Alexander Y.; Chernyh, Nikolai A.; Mardanov, Andrey V.; Ravin, Nikolai V.; Karnachuk, Olga V.; Bonch-Osmolovskaya, Elizaveta A.

    2016-01-01

    The goal of this work was to study the diversity of microorganisms inhabiting a deep subsurface aquifer system in order to understand their functional roles and interspecies relations formed in the course of buried organic matter degradation. A microbial community of a deep subsurface thermal aquifer in the Tomsk Region, Western Siberia was monitored over the course of 5 years via a 2.7 km deep borehole 3P, drilled down to a Palaeozoic basement. The borehole water discharges with a temperature of ca. 50°C. Its chemical composition varies, but it steadily contains acetate, propionate, and traces of hydrocarbons and gives rise to microbial mats along the surface flow. Community analysis by PCR-DGGE 16S rRNA genes profiling, repeatedly performed within 5 years, revealed several dominating phylotypes consistently found in the borehole water, and highly variable diversity of prokaryotes, brought to the surface with the borehole outflow. The major planktonic components of the microbial community were Desulfovirgula thermocuniculi and Methanothermobacter spp. The composition of the minor part of the community was unstable, and molecular analysis did not reveal any regularity in its variations, except some predominance of uncultured Firmicutes. Batch cultures with complex organic substrates inoculated with water samples were set in order to enrich prokaryotes from the variable part of the community. PCR-DGGE analysis of these enrichments yielded uncultured Firmicutes, Chloroflexi, and Ignavibacteriae. A continuous-flow microaerophilic enrichment culture with a water sample amended with acetate contained Hydrogenophilus thermoluteolus, which was previously detected in the microbial mat developing at the outflow of the borehole. Cultivation results allowed us to assume that variable components of the 3P well community are hydrolytic organotrophs, degrading buried biopolymers, while the constant planktonic components of the community degrade dissolved fermentation products

  11. Hydraulic conductivity of the High Plains Aquifer re-evaluated using surface drainage patterns

    NASA Astrophysics Data System (ADS)

    Luo, Wei; Pederson, Darryll T.

    2012-01-01

    The High Plains Aquifer (HPA), underlying parts of 8 states from South Dakota to Texas, is one of the largest fresh water aquifers in the world and accounts for 30% of the groundwater used for irrigation in the US. Determining the distribution of HPA's hydraulic conductivity (K) is critical for water management and addressing water quality issues. K is traditionally estimated from well pumping data coupled with computer modeling and is known to be highly variable, spanning several orders of magnitude for the same type of rock. Here we show that applying our innovative method of determining effective horizontal K to HPA (based on surface drainage patterns and a dynamic equilibrium assumption) produced results generally consistent with those from traditional methods but reveals much more detailed spatial variation. With the exception of a few places such as the Sand Hills area, our results also show for the first time (to the best of our knowledge) a distinct relationship between surface stream drainage density and subsurface aquifer K in a major aquifer system on a regional scale. Because aquifer particle size strongly controls K, our results can be used to study patterns of past sediment movement and deposition.

  12. Introduction: energy and the subsurface.

    PubMed

    Christov, Ivan C; Viswanathan, Hari S

    2016-10-13

    This theme issue covers topics at the forefront of scientific research on energy and the subsurface, ranging from carbon dioxide (CO2) sequestration to the recovery of unconventional shale oil and gas resources through hydraulic fracturing. As such, the goal of this theme issue is to have an impact on the scientific community, broadly, by providing a self-contained collection of articles contributing to and reviewing the state-of-the-art of the field. This collection of articles could be used, for example, to set the next generation of research directions, while also being useful as a self-study guide for those interested in entering the field. Review articles are included on the topics of hydraulic fracturing as a multiscale problem, numerical modelling of hydraulic fracture propagation, the role of computational sciences in the upstream oil and gas industry and chemohydrodynamic patterns in porous media. Complementing the reviews is a set of original research papers covering growth models for branched hydraulic crack systems, fluid-driven crack propagation in elastic matrices, elastic and inelastic deformation of fluid-saturated rock, reaction front propagation in fracture matrices, the effects of rock mineralogy and pore structure on stress-dependent permeability of shales, topographic viscous fingering and plume dynamics in porous media convection.This article is part of the themed issue 'Energy and the subsurface'.

  13. Induction heaters used to heat subsurface formations

    DOEpatents

    Nguyen, Scott Vinh [Houston, TX; Bass, Ronald M [Houston, TX

    2012-04-24

    A heating system for a subsurface formation includes an elongated electrical conductor located in the subsurface formation. The electrical conductor extends between at least a first electrical contact and a second electrical contact. A ferromagnetic conductor at least partially surrounds and at least partially extends lengthwise around the electrical conductor. The electrical conductor, when energized with time-varying electrical current, induces sufficient electrical current flow in the ferromagnetic conductor such that the ferromagnetic conductor resistively heats to a temperature of at least about 300.degree. C.

  14. Subsurface Microbes Expanding the Tree of Life

    SciTech Connect

    Banfield, Jillian

    2015-05-11

    Jillian Banfield, Ph.D., UC Berkeley Professor and Berkeley Lab Earth Sciences Division staff scientist and long-time user of the DOE Joint Genome Institute’s resources shares her perspective on how the DOE JGI helps advance her research addressing knowledge gaps related to the roles of subsurface microbial communities in biogeochemical cycling. The video was filmed near the town of Rifle, Colorado at the primary field site for Phase I of the Subsurface Systems Scientific Focus Area 2.0 sponsored by the DOE Office of Biological and Environmental Research.

  15. Subsurface Microbes Expanding the Tree of Life

    ScienceCinema

    Banfield, Jillian

    2016-07-12

    Jillian Banfield, Ph.D., UC Berkeley Professor and Berkeley Lab Earth Sciences Division staff scientist and long-time user of the DOE Joint Genome Institute’s resources shares her perspective on how the DOE JGI helps advance her research addressing knowledge gaps related to the roles of subsurface microbial communities in biogeochemical cycling. The video was filmed near the town of Rifle, Colorado at the primary field site for Phase I of the Subsurface Systems Scientific Focus Area 2.0 sponsored by the DOE Office of Biological and Environmental Research.

  16. Effects of chemical oxygen demand (COD)/N ratios on pollutants removal in the subsurface wastewater infiltration systems with/without intermittent aeration.

    PubMed

    Song, Siyu; Pan, Jing; Wu, Shiwei; Guo, Yijing; Yu, Jingxiao; Shan, Qingchi

    2016-01-01

    The matrix oxidation reduction potential level, organic pollutants and nitrogen removal performances of eight subsurface wastewater infiltration systems (SWISs) (four with intermittent aeration, four without intermittent aeration) fed with influent chemical oxygen demand (COD)/N ratio of 3, 6, 12 and 18 were investigated. Nitrification of non-aerated SWISs was poor due to oxygen deficiency while higher COD/N ratios further led to lower COD and nitrogen removal rate. Intermittent aeration achieved almost complete nitrification, which successfully created aerobic conditions in the depth of 50 cm and did not change anoxic or anaerobic conditions in the depth of 80 and 110 cm. The sufficient carbon source in high COD/N ratio influent greatly promoted denitrification in SWISs with intermittent aeration. High average removal rates of COD (95.68%), ammonia nitrogen (NH4(+)-N) (99.32%) and total nitrogen (TN) (89.65%) were obtained with influent COD/N ratio of 12 in aerated SWISs. The results suggest that intermittent aeration was a reliable option to achieve high nitrogen removal in SWISs, especially with high COD/N ratio wastewater.

  17. Drainage hydraulics of permeable friction courses

    NASA Astrophysics Data System (ADS)

    Charbeneau, Randall J.; Barrett, Michael E.

    2008-04-01

    This paper describes solutions to the hydraulic equations that govern flow in permeable friction courses (PFC). PFC is a layer of porous asphalt approximately 50 mm thick that is placed as an overlay on top of an existing conventional concrete or asphalt road surface to help control splash and hydroplaning, reduce noise, and enhance quality of storm water runoff. The primary objective of this manuscript is to present an analytical system of equations that can be used in design and analysis of PFC systems. The primary assumptions used in this analysis are that the flow can be modeled as one-dimensional, steady state Darcy-type flow and that slopes are sufficiently small so that the Dupuit-Forchheimer assumptions apply. Solutions are derived for cases where storm water drainage is confined to the PFC bed and for conditions where the PFC drainage capacity is exceeded and ponded sheet flow occurs across the pavement surface. The mathematical solutions provide the drainage characteristics (depth and residence time) as a function of rainfall intensity, PFC hydraulic conductivity, pavement slope, and maximum drainage path length.

  18. Collaborative Research: Nanopore Confinement of C-H-O Mixed Volatile Fluids Relevant to Subsurface Energy Systems

    SciTech Connect

    Grady, Brian P.

    2015-03-11

    The scientific objective of this proposal was to obtain a fundamental atomic- to macro-scale understanding of the sorptivity, structure and dynamics of simple and complex hydrocarbon (HC) fluids at mineral surfaces or within nanoporous matrices over temperatures, pressures and compositions encountered in near-surface and shallow crustal environments. The research supported by this award was complementary to that conducted by the group of Prof. David cole at Ohio State University. The scope of the present award was to utilize molecular-level modeling to provide critically important insights into the interfacial properties of mineral-volatile systems, assist in the interpretation of experimental data and predict fluid behavior beyond the limits of current experimental capability. During the past three years the effort has focused primarily on the behavior of C-H volatiles including methane (CH4) and propane (C3H8), mixed-volatile systems including hydrocarbon - CO2 with and without H2O present. The long-range goal is to quantitatively link structure, dynamics and reactivity in complex mineral-/C-H-O systems from the atomic to the molecular to the macroscopic levels. The results are relevant to areas of growing importance such as gas shale, HC-bearing hydrothermal systems, and CO2 storage.

  19. Applicability of grid-net detection system for landfill leachate and diesel fuel release in the subsurface

    NASA Astrophysics Data System (ADS)

    Oh, Myounghak; Seo, Min Woo; Lee, Seunghak; Park, Junboum

    2008-02-01

    The grid-net system estimating the electrical conductivity changes was evaluated as a potential detection system for the leakage of diesel fuel and landfill leachate. Aspects of electrical conductivity changes were varied upon the type of contaminant. The electrical conductivity in the homogeneous mixtures of soil and landfill leachate linearly increased with the ionic concentration of pore fluid, which became more significant at higher volumetric water contents. However, the electrical conductivity in soil/diesel fuel mixture decreased with diesel fuel content and it was more significant at lower water contents. The electrode spacing should be determined by considering the type of contaminant to enhance the electrode sensitivity especially when two-electrode sensors are to be used. The electrode sensitivity for landfill leachate was constantly maintained regardless of the electrode spacings while that for the diesel fuel significantly increased at smaller electrode spacings. This is possibly due to the fact that the insulating barrier effect of the diesel fuel in non-aqueous phase was less predominant at large electrode spacing because electrical current can form the round-about paths over the volume with relatively small diesel fuel content. The model test results showed that the grid-net detection system can be used to monitor the leakage from waste landfill and underground storage tank sites. However, for a successful application of the detection system in the field, data under various field conditions should be accumulated.

  20. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Artificial Drainage (1992) and Irrigation (1997)

    USGS Publications Warehouse

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the estimated area of artifical drainage for the year 1992 and irrigation types for the year 1997 compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). The source data sets were derived from tabular National Resource Inventory (NRI) data sets created by the National Resources Conservation Service (NRCS, U.S. Department of Agriculture, 1995, 2000). Artificial drainage is defined as subsurface drains and ditches. Irrigation types are defined as gravity and pressure. Subsurface drains are described as conduits, such as corrugated plastic tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey drainage. Surface drainage field ditches are described as graded ditches for collecting excess water. Gravity irrigation source is described as irrigation delivered to the farm and/or field by canals or pipelines open to the atmosphere; and water is distributed by the force of gravity down the field by: (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, and water is distributed across the field by: (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, big gun, or fixed set sprinklers), or (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). NRI data do not include Federal lands and are thus excluded from this dataset. The tabular data for drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, U.S. Geological Survey, written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced version of the National Land Cover Dataset (NLCDe, Nakagaki and others, 2007). The MRB_E2RF1 catchments are based on a modified

  1. Assessment and synthesis of 50 years of published drainage phosphorus losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence of artificial drainage systems in intensively cropped areas across North America combined with the importance of freshwater resources in these regions has created a critical intersection where understanding drainage phosphorus (P) transport is vital. In this study, drainage nutrient ...

  2. Evolution of supraglacial brittle and ductile structures and drainage systems at a partly debris-covered alpine valley glacier during a 15 yr period

    NASA Astrophysics Data System (ADS)

    Kellerer-Pirklbauer, Andreas; Kulmer, Bernd

    2016-04-01

    Based on five glacier stages (1998, 2003, 2006, 2009 and 2012) covering a period of 15 years, supraglacial crevasses and other structures as well as the drainage system at the tongue of Pasterze Glacier were mapped and interpreted. Pasterze Glacier is the largest glacier (c.16.5 km2) of the entire Eastern European Alps located in the Hohe Tauern Range, Central Austria at 47°05'N and 12°43'E. The glacier is in a stage of rapid recession and downwasting. The tongue is connected with the firn area by a mighty ice fall. 75% of the c.4.5 km long glacier tongue is covered by a supraglacial debris cover affecting glacier surface morphology related to differential ablation influencing the glacier's stress and strain field. High resolution orthoimagery and digital elevation models/DEM (both data sets with 20-50 cm grid resolution) were analysed. A structure glaciological mapping key was applied to discern relevant brittle (normal faults, thrust faults, strike-slip faults commonly associated with and en èchelon structures, and ice disintegration expressed as normal faults) and ductile structures (band ogives). Additionally, a geometric mapping key was used differentiating between chevron, splaying, transverse, and longitudinal crevasses as well as complex crevasse fields related to ice disintegration (commonly circular and semi-circular collapse features). The drainage system was mapped differentiating between supraglacial channels and moulins. Observations made during annual glacier measurement campaigns were additionally considered. Results indicate that the lower half of the glacier tongue was characterised during the observation period by ice disintegration (with semi-circular collapse features since 2003 near the glacier terminus and since 2009 in the central part) and thrust faults with downslope convexity (steady upslope migration of first occurrence during the observation period). In general, the crevasse density increased towards the left (NE), less debris

  3. Impact of runoff infiltration on contaminant accumulation and transport in the soil/filter media of Sustainable Urban Drainage Systems: A literature review.

    PubMed

    Tedoldi, Damien; Chebbo, Ghassan; Pierlot, Daniel; Kovacs, Yves; Gromaire, Marie-Christine

    2016-11-01

    The increasing use of Sustainable Urban Drainage Systems (SUDS) for stormwater management raises some concerns about the fate of ubiquitous runoff micropollutants in soils and their potential threat to groundwater. This question may be addressed either experimentally, by sampling and analyzing SUDS soil after a given operating time, or with a modeling approach to simulate the fate and transport of contaminants. After briefly reminding the processes responsible for the retention, degradation, or leaching of several urban-sourced contaminants in soils, this paper presents the state of the art about both experimental and modeling assessments. In spite of noteworthy differences in the sampling protocols, the soil parameters chosen as explanatory variables, and the methods used to evaluate the site-specific initial concentrations, most investigations undoubtedly evidenced a significant accumulation of metals and/or hydrocarbons in SUDS soils, which in the majority of the cases appears to be restricted to the upper 10 to 30cm. These results may suggest that SUDS exhibit an interesting potential for pollution control, but antinomic observations have also been made in several specific cases, and the inter-site concentration variability is still difficult to appraise. There seems to be no consensus regarding the level of complexity to be used in models. However, the available data deriving from experimental studies is generally limited to the contamination profiles and a few parameters of the soil, as a result of which "complex" models (including colloid-facilitated transport for example) appear to be difficult to validate before using them for predictive evaluations.

  4. Characterization of limestone reacted with acid-mine drainage in a pulsed limestone bed treatment system at the Friendship Hill National Historical Site, Pennsylvania, USA