Nontoxic chemical process for in situ permeability enhancement and accelerated decontamination of fine-grain subsurface sediments

DOEpatents

Kansa, E.J.; Wijesinghe, A.M.; Viani, B.E.

1997-01-14

The remediation of heterogeneous subsurfaces is extremely time consuming and expensive with current and developing technologies. Although such technologies can adequately remove contaminants in the high hydraulic conductivity, coarse-grained sediments, they cannot access the contaminated low hydraulic conductivity fine-grained sediments. The slow bleed of contaminants from the fine-grained sediments is the primary reason why subsurface remediation is so time-consuming and expensive. This invention addresses the problem of remediating contaminated fine-grained sediments. It is intended that, in the future, a heterogeneous site be treated by a hybrid process that first remediates the high hydraulic conductivity, coarse-grained sediments, to be followed by the process, described in this invention, to treat the contaminated low hydraulic conductivity fine-grained sediments. The invention uses cationic flocculants and organic solvents to collapse the swelling negative double layer surrounding water saturated clay particles, causing a flocculated, cracked clay structure. The modification of the clay fabric in fine-grained sediments dramatically increases the hydraulic conductivity of previously very tight clays many orders of magnitude. 8 figs.

Nontoxic chemical process for in situ permeability enhancement and accelerated decontamination of fine-grain subsurface sediments

DOEpatents

Kansa, Edward J.; Wijesinghe, Ananda M.; Viani, Brian E.

1997-01-01

The remediation of heterogeneous subsurfaces is extremely time consuming and expensive with current and developing technologies. Although such technologies can adequately remove contaminants in the high hydraulic conductivity, coarse-grained sediments, they cannot access the contaminated low hydraulic conductivity fine-grained sediments. The slow bleed of contaminants from the fine-grained sediments is the primary reason why subsurface remediation is so time-consuming and expensive. This invention addresses the problem of remediating contaminated fine-grained sediments. It is intended that, in the future, a heterogeneous site be treated by a hybrid process that first remediates the high hydraulic conductivity, coarse-grained sediments, to be followed by the process, described in this invention, to treat the contaminated low hydraulic conductivity fine-grained sediments. The invention uses cationic flocculents and organic solvents to collapse the swelling negative double layer surrounding water saturated clay particles, causing a flocculated, cracked clay structure. The modification of the clay fabric in fine-grained sediments dramatically increases the hydraulic conductivity of previously very tight clays many orders of magnitude.

Process envelopes for stabilisation/solidification of contaminated soil using lime-slag blend.

PubMed

Kogbara, Reginald B; Yi, Yaolin; Al-Tabbaa, Abir

2011-09-01

Stabilisation/solidification (S/S) has emerged as an efficient and cost-effective technology for the treatment of contaminated soils. However, the performance of S/S-treated soils is governed by several intercorrelated variables, which complicates the optimisation of the treatment process design. Therefore, it is desirable to develop process envelopes, which define the range of operating variables that result in acceptable performance. In this work, process envelopes were developed for S/S treatment of contaminated soil with a blend of hydrated lime (hlime) and ground granulated blast furnace slag (GGBS) as the binder (hlime/GGBS = 1:4). A sand contaminated with a mixture of heavy metals and petroleum hydrocarbons was treated with 5%, 10% and 20% binder dosages, at different water contents. The effectiveness of the treatment was assessed using unconfined compressive strength (UCS), permeability, acid neutralisation capacity and contaminant leachability with pH, at set periods. The UCS values obtained after 28 days of treatment were up to ∼800 kPa, which is quite low, and permeability was ∼10(-8) m/s, which is higher than might be required. However, these values might be acceptable in some scenarios. The binder significantly reduced the leachability of cadmium and nickel. With the 20% dosage, both metals met the waste acceptance criteria for inert waste landfill and relevant environmental quality standards. The results show that greater than 20% dosage would be required to achieve a balance of acceptable mechanical and leaching properties. Overall, the process envelopes for different performance criteria depend on the end-use of the treated material.

Processing liquid organic wastes at the NNL Preston laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coppersthwaite, Duncan; Greenwood, Howard; Docrat, Tahera

2013-07-01

Organic compounds of various kinds have been used in the nuclear industry for numerous duties in uranium chemical, metal and ceramic processing plants. In the course of the various operations undertaken, these organic compounds have become contaminated with uranic material, either accidentally or as an inevitable part of the process. Typically, the chemical/physical form and/or concentration of the uranic content of the organics has prevented disposal. In order to address the issue of contaminated liquid organic wastes, the National Nuclear Laboratory (NNL) has developed a suite of treatments designed to recover uranium and to render the waste suitable for disposal.more » The developed processes are operated at industrial scale via the NNL Preston Laboratory Residue Processing Plant. The Oil Waste Leaching (OWL) Process is a fully industrialised process used for the treatment of contaminated oils with approximately 200 tonnes of uranium contaminated oil being treated to date. The process was originally developed for the treatment of contaminated tributyl phosphate and odourless kerosene which had been adsorbed onto sawdust. However, over the years, the OWL process has been refined for a range of oils including 'water emulsifiable' cutting oils, lubricating oils, hydraulic oils/fluids and 'Fomblin' (fully fluorinated) oils. Chemically, the OWL process has proved capable of treating solvents as well as oils but the highly volatile/flammable nature of many solvents has required additional precautions compared with those required for oil treatment. These additional precautions led to the development of the Solvent Treatment Advanced Rig (STAR), an installation operated under an inert atmosphere. STAR is a small 'module' (100 dm{sup 3} volume) which allows the treatment of both water miscible and immiscible solvents. This paper discusses the challenges associated with the treatment of liquid organic wastes and the process developments which have allowed a wide range of materials to be successfully treated. (authors)« less

Electrochemical Processes for In-Situ Treatment of Contaminated Soils - Final Report - 09/15/1996 - 01/31/2001

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Chin-Pao

2001-05-31

This project will study electrochemical processes for the in situ treatment of soils contaminated by mixed wastes, i.e., organic and inorganic. Soil samples collected form selected DOE waste sites will be characterized for specific organic and metal contaminants and hydraulic permeability. The soil samples are then subject to desorption experiments under various physical-chemical conditions such as pH and the presence of surfactants. Batch electro-osmosis experiments will be conducted to study the transport of contaminants in the soil-water systems. Organic contaminants that are released from the soil substrate will be treated by an advanced oxidation process, i.e., electron-Fantan. Finally, laboratory reactormore » integrating the elector-osmosis and elector-Fantan processes will be used to study the treatment of contaminated soil in situ.« less

Bioremediation techniques applied to aqueous media contaminated with mercury.

PubMed

Velásquez-Riaño, Möritz; Benavides-Otaya, Holman D

2016-12-01

In recent years, the environmental and human health impacts of mercury contamination have driven the search for alternative, eco-efficient techniques different from the traditional physicochemical methods for treating this metal. One of these alternative processes is bioremediation. A comprehensive analysis of the different variables that can affect this process is presented. It focuses on determining the effectiveness of different techniques of bioremediation, with a specific consideration of three variables: the removal percentage, time needed for bioremediation and initial concentration of mercury to be treated in an aqueous medium.

OMNIgene.SPUTUM suppresses contaminants while maintaining Mycobacterium tuberculosis viability and obviates cold-chain transport.

PubMed

Azam, Khalide; Cadir, Nureisha; Madeira, Carla; Gillespie, Stephen H; Sabiiti, Wilber

2018-01-01

Tuberculosis (TB) diagnostics are centralised, requiring long-distance transportation of specimens in most resource-limited settings. We evaluated the ability of OMNIgene.SPUTUM (OM-S) to obviate cold-chain transport of TB specimens. A two-arm (same-day and after 5 days sample processing) study was conducted to assess contamination rates and Mycobacterium tuberculosis viability in OM-S-treated samples against the standard decontamination procedure (SDP) in Mozambique, using Lowenstein Jensen (LJ) and mycobacterial growth indicator tube (MGIT) culture and molecular bacterial load assay. 270 specimens were processed using OM-S and SDP in same-day and 5-day arms. Contamination was lower in OM-S-treated than SDP-treated cultures: 12% versus 15% and 2% versus 27% in the same-day and 5-day arms, respectively. M. tuberculosis recovery in OM-S-treated LJ cultures was 10% and 56% higher in the same-day and 5-day arms, respectively, than SDP-treated cultures, but lower in MGIT (52% and 28% lower in the same-day and 5-day arms, respectively). M. tuberculosis viable count was 1log estimated CFU·mL -1 lower in 5-day OM-S-treated sputa. OM-S was more effective at liquefying sputum with a shorter sample processing time: 22 min for culture. OM-S is simple to use and has demonstrated a high potency to suppress contaminants, maintenance of viability at ambient temperatures and higher M. tuberculosis recovery, particularly in the solid LJ cultures. Optimisation of OM-S to achieve higher MGIT culture positivity and shorter time to result will increase its application and utility in the clinical management of TB.

OMNIgene.SPUTUM suppresses contaminants while maintaining Mycobacterium tuberculosis viability and obviates cold-chain transport

PubMed Central

Azam, Khalide; Cadir, Nureisha; Madeira, Carla; Gillespie, Stephen H.; Sabiiti, Wilber

2018-01-01

Tuberculosis (TB) diagnostics are centralised, requiring long-distance transportation of specimens in most resource-limited settings. We evaluated the ability of OMNIgene.SPUTUM (OM-S) to obviate cold-chain transport of TB specimens. A two-arm (same-day and after 5 days sample processing) study was conducted to assess contamination rates and Mycobacterium tuberculosis viability in OM-S-treated samples against the standard decontamination procedure (SDP) in Mozambique, using Lowenstein Jensen (LJ) and mycobacterial growth indicator tube (MGIT) culture and molecular bacterial load assay. 270 specimens were processed using OM-S and SDP in same-day and 5-day arms. Contamination was lower in OM-S-treated than SDP-treated cultures: 12% versus 15% and 2% versus 27% in the same-day and 5-day arms, respectively. M. tuberculosis recovery in OM-S-treated LJ cultures was 10% and 56% higher in the same-day and 5-day arms, respectively, than SDP-treated cultures, but lower in MGIT (52% and 28% lower in the same-day and 5-day arms, respectively). M. tuberculosis viable count was 1log estimated CFU·mL−1 lower in 5-day OM-S-treated sputa. OM-S was more effective at liquefying sputum with a shorter sample processing time: 22 min for culture. OM-S is simple to use and has demonstrated a high potency to suppress contaminants, maintenance of viability at ambient temperatures and higher M. tuberculosis recovery, particularly in the solid LJ cultures. Optimisation of OM-S to achieve higher MGIT culture positivity and shorter time to result will increase its application and utility in the clinical management of TB. PMID:29479537

40 CFR 419.24 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... section. (e) Effluent limitations for contaminated runoff. The following effluent limitations constitute... attributable to contaminated runoff which may be discharged after the application of the best conventional... contaminated runoff and is not commingled or treated with process wastewater, it may be discharged if it does...

40 CFR 419.44 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... section. (e) Effluent limitations for contaminated runoff. The following effluent limitations constitute... attributable to contaminated runoff which may be discharged after the application of the best conventional... contaminated runoff and is not commingled or treated with process wastewater, it may be discharged if it does...

40 CFR 419.14 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (b) of this section. (e) Effluent limitations for contaminated runoff. The following effluent... paragraph and attributable to contaminated runoff which may be discharged after the application of the best... solely of contaminated runoff and is not commingled or treated with process wastewater, it may be...

40 CFR 419.54 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (b) of this section. (e) Effluent limitations for contaminated runoff. The following effluent... paragraph and attributable to contaminated runoff which may be discharged after the application of the best... solely of contaminated runoff and is not commingled or treated with process wastewater, it may be...

Advanced Oxidation Process sanitization of hatching eggs reduces Salmonella in broiler chicks.

PubMed

Rehkopf, A C; Byrd, J A; Coufal, C D; Duong, T

2017-10-01

The microbial quality of eggs entering the hatchery is an important critical control point for biosecurity, pathogen reduction, and food safety programs in poultry production. Developing interventions to reduce Salmonella contamination of eggs is important to improving the microbial food safety of poultry and poultry products. The hydrogen peroxide (H2O2) and ultraviolet light (UV) Advanced Oxidation Process (AOP) has been previously demonstrated to be effective in reducing Salmonella on the surface of experimentally contaminated eggs. The objective of this study was to evaluate the effect of treating eggs with an egg-sanitizing apparatus using the H2O2/UV AOP on Salmonella contamination during incubation, hatching, and in broiler chicks during grow-out. Experimentally contaminated eggs were treated using the automated H2O2/UV AOP egg sanitizer and incubated for 21 d. AOP sanitization reduced Salmonella up to 7 log10 cfu egg-1 (P < 0.05) from the surface of experimentally contaminated eggs and reduced the number of Salmonella positive eggs by up to 75% (P < 0.05) when treated 1 h post-inoculation. AOP treatment also reduced the number of Salmonella-positive eggs during incubation. Additionally, Salmonella was recovered from more chicks hatched from untreated eggs than from eggs treated using the H2O2/UV AOP egg sanitizer (P < 0.05) through 14 d posthatch. These data suggest reduction of Salmonella contamination on the surface of eggs using the H2O2/UV AOP egg sanitizer prior to incubation may reduce the gastrointestinal colonization of chicks by Salmonella. © 2017 Poultry Science Association Inc.

Treating an aged pentachlorophenol- (PCP-) contaminated soil through three sludge handling processes, anaerobic sludge digestion, post-sludge digestion and sludge land application.

PubMed

Chen, S T; Berthouex, P M

2001-01-01

The extensive pentachlorophenol (PCP) contamination and its increasing treatment costs motivate the search for a more competitive treatment alternative. In a municipal wastewater treatment plant, anaerobic sludge-handling processes comprises three bio-processes, namely the anaerobic sludge digestion, post-sludge digestion and sludge land application, which reduce sludge organic content and make sludge a good fertilizer for land application. Availability and effectiveness make the anaerobic sludge handling processes potential technologies to treat PCP-contaminated soil. The technical feasibility of using anaerobic sludge bioprocesses was studied by treating PCP soil in two pilot digesters to simulate the primary sludge digestion, in serum bottles to mimic the post-sludge digestion, and in glass pans to represent the on-site sludge application. For primary digestion, the results showed that up to 0.98 and 0.6 mM of chemical and soil PCP, respectively, were treated at nearly 100% and 97.5% efficiencies. The PCP was transformed 95% to 3-MCP, 4.5% to 3,4-DCP, and 0.5% to 3,5-DCP. For post-digestion, 100% pure chemical PCP and greater than 95% soil PCP were removed in less than 6 months with no chlorophenol residues of any kind. Complete removal of PCP by-products makes this process a good soil cleanup method. For on-site treatment, PCP was efficiently treated by multiple sludge application; however, the PCP residue was observed due to the high initial PCP content in soil. Overall, more mass PCP per unit sludge per day was processed using the primary sludge digestion than the on-site soil treatment or post-sludge digestion. And, sludge acclimation resulted in better PCP treatment efficiencies with all three processes.

Near Critical/Supercritical Carbon Dioxide Extraction for Treating Contaminated Bilgewater

DTIC Science & Technology

2000-02-24

SUMMARY i TABLE OF CONTENTS ii LIST OF FIGURES iii LIST OF TABLES iii 1. INTRODUCTION 1 1.1 Current Treatment Processes 1 2. SUPERCRITICAL...Treatment Processes Historically, the Navy has relied on gravimetric separation to remove oily contaminants from bilgewater. Most ships contain one...continuously changes the orientation of the separator with respect to gravity, lowering the effectiveness of a separation process that relies on subtle

DEMONSTRATION BULLETIN: IN SITU VITRIFICATION - GEOSAFE CORPORATION

EPA Science Inventory

in Situ Vitrification (ISV) is designed to treat soils, sludges, sediments, and mine tailings contaminated with organic and inorganic compounds. The process uses electrical current to heat (mett) and vitrify the soil in place. Organic contaminants are decomposed by the extreme h...

SITE TECHNOLOGY CAPSULE: DYNAPHORE, INC., FORAGER™ SPONGE TECHNOLOGY

EPA Science Inventory

The Forager™ Sponge is a volume reduction technology in which heavy metal contaminants from an aqueous medium are selectively concentrated into a smaller volume for facilitated disposal. The technology treats contaminated groundwater, surface waters, and process waters by absorbi...

Considerations in Deciding to Treat Contaminated Unsaturated Soils In Situ

EPA Pesticide Factsheets

The purpose of this Issue Paper is to assist the user in deciding if in situ treatment of contaminated soil is a potentially feasible remedial alternative and to assist in the process of reviewing and screening in situ technologies.

Cross-Contamination of Residual Emerging Contaminants and Antibiotic Resistant Bacteria in Lettuce Crops and Soil Irrigated with Wastewater Treated by Sunlight/H2O2.

PubMed

Ferro, Giovanna; Polo-López, María I; Martínez-Piernas, Ana B; Fernández-Ibáñez, Pilar; Agüera, Ana; Rizzo, Luigi

2015-09-15

The sunlight/H2O2 process has recently been considered as a sustainable alternative option compared to other solar driven advanced oxidation processes (AOPs) in advanced treatment of municipal wastewater (WW) to be reused for crop irrigation. Accordingly, in this study sunlight/H2O2 was used as disinfection/oxidation treatment for urban WW treatment plant effluent in a compound parabolic collector photoreactor to assess subsequent cross-contamination of lettuce and soil by contaminants of emerging concern (CECs) (determined by QuEChERS extraction and LC-QqLIT-MS/MS analysis) and antibiotic resistant (AR) bacteria after irrigation with treated WW. Three CECs (carbamazepine (CBZ), flumequine (FLU), and thiabendazole (TBZ) at 100 μg L(-1)) and two AR bacterial strains (E. coli and E. faecalis, at 10(5) CFU mL(-1)) were spiked in real WW. A detection limit (DL) of 2 CFU mL(-1) was reached after 120 min of solar exposure for AR E. coli, while AR E. faecalis was more resistant to the disinfection process (240 min to reach DL). CBZ and TBZ were poorly removed after 90 min (12% and 50%, respectively) compared to FLU (94%). Lettuce was irrigated with treated WW for 5 weeks. CBZ and TBZ were accumulated in soil up to 472 ng g(-1) and 256 ng g(-1) and up-taken by lettuce up to 109 and 18 ng g(-1), respectively, when 90 min treated WW was used for irrigation; whereas no bacteria contamination was observed when the bacterial density in treated WW was below the DL. A proper treatment time (>90 min) should be guaranteed in order to avoid the transfer of pathogens from disinfected WW to irrigated crops and soil.

Method of treating contaminated HEPA filter media in pulp process

DOEpatents

Hu, Jian S.; Argyle, Mark D.; Demmer, Ricky L.; Mondok, Emilio P.

2003-07-29

A method for reducing contamination of HEPA filters with radioactive and/or hazardous materials is described. The method includes pre-processing of the filter for removing loose particles. Next, the filter medium is removed from the housing, and the housing is decontaminated. Finally, the filter medium is processed as pulp for removing contaminated particles by physical and/or chemical methods, including gravity, flotation, and dissolution of the particles. The decontaminated filter medium is then disposed of as non-RCRA waste; the particles are collected, stabilized, and disposed of according to well known methods of handling such materials; and the liquid medium in which the pulp was processed is recycled.

Modified resins for solid-phase extraction

DOEpatents

Fritz, James S.; Sun, Jeffrey J.

1993-07-27

A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

Modified resins for solid-phase extraction

DOEpatents

Fritz, James S.; Sun, Jeffrey J.

1991-12-10

A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

Evaluation of a Candidate Trace Contaminant Control Subsystem Architecture: The High Velocity, Low Aspect Ratio (HVLA) Adsorption Process

NASA Technical Reports Server (NTRS)

Kayatin, Matthew J.; Perry, Jay L.

2017-01-01

Traditional gas-phase trace contaminant control adsorption process flow is constrained as required to maintain high contaminant single-pass adsorption efficiency. Specifically, the bed superficial velocity is controlled to limit the adsorption mass-transfer zone length relative to the physical adsorption bed; this is aided by traditional high-aspect ratio bed design. Through operation in this manner, most contaminants, including those with relatively high potential energy are readily adsorbed. A consequence of this operational approach, however, is a limited available operational flow margin. By considering a paradigm shift in adsorption architecture design and operations, in which flows of high superficial velocity are treated by low-aspect ratio sorbent beds, the range of well-adsorbed contaminants becomes limited, but the process flow is increased such that contaminant leaks or emerging contaminants of interest may be effectively controlled. To this end, the high velocity, low aspect ratio (HVLA) adsorption process architecture was demonstrated against a trace contaminant load representative of the International Space Station atmosphere. Two HVLA concept packaging designs (linear flow and radial flow) were tested. The performance of each design was evaluated and compared against computer simulation. Utilizing the HVLA process, long and sustained control of heavy organic contaminants was demonstrated.

Composition and process for organic and metal contaminant fixation in soil

DOEpatents

Schwitzgebel, Klaus

1994-02-08

A method and compositions using a first ferrous iron containing solution with the iron concentration in excess of theoretical requirements to treat a contaminated site to reduce hexavalent chromium to trivalent chromium and coprecipitate trivalent chromium with other heavy metals and using a second solution of silicate containing a destabilizing salt to form a relatively impermeable gel in the contaminated site thereby fixing metals and organics to the extent that there should be no detectable ground water contamination.

ECOMAT INC. BIOLOGICAL DENITRIFICATION PROCESS, ITER

EPA Science Inventory

EcoMat, Inc. of Hayward, California (EcoMat) has developed an ex situ anoxic biofilter biodenitrification (BDN) process. The process uses specific biocarriers and bacteria to treat nitrate-contaminated water and employs a patented reactor that retains biocarrier within the syste...

Hydroponic phytoremediation of heavy metals and radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartong, J.; Szpak, J.; Hamric, T.

1998-07-01

It is estimated that the Departments of Defense, Energy, and Agriculture will spend up to 300 billion federal dollars on environmental remediation during the next century. Current remediation processes can be expensive, non-aesthetic, and non-versatile. Therefore, the need exists for more innovative and cost effective solutions. Phytoremediation, the use of vegetation for the remediation of contaminated sediments, soils, and ground water, is an emerging technology for treating several categories of persistent, toxic contaminants. Although effective, phytoremediation is still in a developmental stage, and therefore is not a widely accepted technology by regulatory agencies and public groups. Research is currently beingmore » conducted to validate the processes effectiveness as well as increase regulatory and community acceptance. This research will focus on the ability of plants to treat an aquifer contaminated with heavy metals and radionuclides. Specifically, the effectiveness of hydroponically grown dwarf sunflowers and mustard seed will be investigated.« less

SITE TECHNOLOGY CAPSULE: ZENOGEM™ WASTEWATER TREATMENT PROCESS

EPA Science Inventory

Zenon Environmental System's ZenoGem™ Wastewater Treatment Process treats aqueous media contaminated with volatile/semi-volatile organic compounds. This technology combines aerobic biological treatment to remove biodegradable organic compounds with ultrafiltration to separate res...

Effects of materials containing antimicrobial compounds on food hygiene.

PubMed

Møretrø, Trond; Langsrud, Solveig

2011-07-01

Surfaces with microorganisms may transfer unwanted microorganisms to food through cross-contamination during processing and preparation. A high hygienic status of surfaces that come in contact with food is important in order to reduce the risk of cross-contamination. During the last decade, products containing antimicrobial compounds, such as cutting boards, knives, countertops, kitchen utensils, refrigerators, and conveyor belts, have been introduced to the market, claiming hygienic effects. Such products are often referred to as "treated articles." Here we review various aspects related to treated articles intended for use during preparation and processing of food. Regulatory issues and methods to assess antibacterial effects are covered. Different concepts for treated articles as well as their antibacterial activity are reviewed. The effects of products with antimicrobials on food hygiene and safety are discussed. Copyright ©, International Association for Food Protection

ECOMAT INC. BIOLOGICAL DENIFTRICATION PROCESS; SITE TECHNOLOGY CAPSULE

EPA Science Inventory

EcoMat, Inc. of Hayward, California (EcoMat) has developed an ex situ anoxic biofilter biodenitrification (BDN) process. The process uses specific biocarriers and bacteria to treat nitrate-contaminated water and employs a patented reactor that retains biocarrier within the syste...

The impact of different proportions of a treated effluent on the biotransformation of selected micro-contaminants in river water microcosms.

PubMed

Nödler, Karsten; Tsakiri, Maria; Licha, Tobias

2014-10-10

Attenuation of micro-contaminants is a very complex field in environmental science and evidence suggests that biodegradation rates of micro-contaminants in the aqueous environment depend on the water matrix. The focus of the study presented here is the systematic comparison of biotransformation rates of caffeine, carbamazepine, metoprolol, paracetamol and valsartan in river water microcosms spiked with different proportions of treated effluent (0%, 0.1%, 1%, and 10%). Biotransformation was identified as the dominating attenuation process by the evolution of biotransformation products such as atenolol acid and valsartan acid. Significantly decreasing biotransformation rates of metoprolol were observed at treated effluent proportions ≥ 0.1% whereas significantly increasing biotransformation rates of caffeine and valsartan were observed in the presence of 10% treated effluent. Potential reasons for the observations are discussed and the addition of adapted microorganisms via the treated effluent was suggested as the most probable reason. The impact of additional phosphorus on the biodegradation rates was tested and the experiments revealed that phosphorus-limitation was not responsible.

USE OF PLANT AND EARTHWORM BIOASSYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

EPA Science Inventory

Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction tehnology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ear...

USE OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

EPA Science Inventory

Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ...

Reversible photodeposition and dissolution of metal ions

DOEpatents

Foster, Nancy S.; Koval, Carl A.; Noble, Richard D.

1994-01-01

A cyclic photocatalytic process for treating waste water containing metal and organic contaminants. In one embodiment of the method, metal ions are photoreduced onto the photocatalyst and the metal concentrated by resolubilization in a smaller volume. In another embodiment of the method, contaminant organics are first oxidized, then metal ions removed by photoreductive deposition. The present invention allows the photocatalyst to be recycled until nearly complete removal of metal ions and organic contaminants is achieved.

Applications analysis report: Silicate Technology Corporation's solidification/stabilization technology for organic and inorganic contaminants in soils

NASA Astrophysics Data System (ADS)

Bates, E.

1992-12-01

The STC demonstration was conducted under EPA's Superfund Innovative Technology Evaluation (SITE) Program in November, 1990, at the Selma Pressure Treating (SPT) wood preserving site in Selma, California. The SPT site was contaminated with both organics, predominantly pentachlorophenol (PCP), inorganics, mainly arsenic, chromium, and copper. Extensive sampling and analyses were performed on the waste both before and after treatment to compare physical, chemical, and leaching characteristics of raw and treated wastes. STC's contaminated soil treatment process was evaluated based on contaminant mobility measured by numerous leaching tests, structural integrity of the solidified material, measured by physical and engineering tests and morphological examinations; and economic analysis, using cost information supplied by STC and the results of the SITE demonstration, the vendor's design and test data, and other laboratory and field applications of the technology. It discusses the advantages, disadvantages, and limitations, as well as estimated costs of the technology.

Pilot-scale UV/H2O2 study for emerging organic contaminants decomposition.

PubMed

Chu, Xiaona; Xiao, Yan; Hu, Jiangyong; Quek, Elaine; Xie, Rongjin; Pang, Thomas; Xing, Yongjie

2016-03-01

Human behaviors including consumption of drugs and use of personal care products, climate change, increased international travel, and the advent of water reclamation for direct potable use have led to the introduction of significant amounts of emerging organic contaminants into the aqueous environment. In addition, the lower detection limits associated with improved scientific methods of chemical analysis have resulted in a recent increase in documented incidences of these contaminants which previously were not routinely monitored in water. Such contaminants may cause known or suspected adverse ecological and/or human health effects at very low concentrations. Conventional drinking water treatment processes may not effectively remove these organic contaminants. Advanced oxidation process (AOP) is a promising treatment process for the removal of most of these emerging organic contaminants, and has been accepted worldwide as a suitable treatment process. In this study, different groups of emerging contaminants were studied for decomposition efficiency using pilot-scale UV/H2O2 oxidation setup, including EDCs, PPCPs, taste and odor (T&O), and perfluorinated compounds. Results found that MP UV/H2O2 AOP was efficient in removing all the selected contaminants except perfluorinated compounds. Study of the kinetics of the process showed that both light absorption and quantum yield of each compound affected the decomposition performance. Analysis of water quality parameters of the treated water indicated that the outcome of both UV photolysis and UV/H2O2 processes can be affected by changes in the feed water quality.

EPA SITE DEMONSTRATION OF THE BIOTROL SOIL WASHING PROCESS

EPA Science Inventory

A pilot-scale soil washing process, patented by BioTrol, Inc., was demonstrate on soil contaminated by wood treating waste, primarily pentachlorophenol (PCP) and creosote-derived polynuclear aromatic hydrocarbons (PAHs). Although soil washing was the main object of this demonstra...

Use of sugarcane filter cake and nitrogen, phosphorus and potassium fertilization in the process of bioremediation of soil contaminated with diesel.

PubMed

Tellechea, Fernando Reynel Fundora; Martins, Marco Antônio; da Silva, Alexsandro Araujo; da Gama-Rodrigues, Emanuela Forestieri; Martins, Meire Lelis Leal

2016-09-01

This study evaluated the use of sugarcane filter cake and nitrogen, phosphorus and potassium (NPK) fertilization in the bioremediation of a soil contaminated with diesel fuel using a completely randomized design. Five treatments (uncontaminated soil, T1; soil contaminated with diesel, T2; soil contaminated with diesel and treated with 15 % (wt) filter cake, T3; soil contaminated with diesel and treated with NPK fertilizer, T4; and soil contaminated with diesel and treated with 15 % (wt) filter cake and NPK fertilizer, T5) and four evaluation periods (1, 60, 120, and 180 days after the beginning of the experiment) were used according to a 4 × 5 factorial design to analyze CO2 release. The variables total organic carbon (TOC) and total petroleum hydrocarbons (TPH) remaining in the soil were analyzed using a 5 × 2 factorial design, with the same treatments described above and two evaluation periods (1 and 180 days after the beginning of the experiment). In T3 and T5, CO2 release was significantly higher, compared with the other treatments. Significant TPH removal was observed on day 180, when percent removal values were 61.9, 70.1, 68.2, and 75.9 in treatments T2, T3, T4, and T5, respectively, compared with the initial value (T1).

Contamination of soils with microbial pathogens originating from effluent water used for agricultural irrigation

NASA Astrophysics Data System (ADS)

Bernstein, N.

2009-04-01

The use of wastewater for agricultural irrigation is steadily increasing world-wide and due to shortages of fresh water is common today in most arid regions of the world. The use of treated wastewater for agricultural irrigation may result in soil exposure to pathogens, creating potential public health problems. A variety of human pathogens are present in raw sewage water. Although their concentrations decrease during the wastewater reclamation process, the secondary treated effluents most commonly used for irrigation today still contain bacterial human pathogens. A range of bacterial pathogens, introduced through contaminated irrigation water or manure, are capable of surviving for long periods in soil and water where they have the potential to contaminate crops in the field. Therefore, there is a risk of direct contamination of crops by human pathogens from the treated effluents used for irrigation, as well as a risk of indirect contamination of the crops from contaminated soil at the agricultural site. Contradictory to previous notion, recent studies have demonstrated that human pathogens can enter plants through their roots and translocate and survive in edible, aerial plant tissues. The practical implications of these new findings for food safety are still not clear, but no doubt reflect the pathogenic microorganisms' ability to survive and multiply in the irrigated soil, water, and the harvested edible crop.

Treatment of Chlorinated Aliphatic Contamination of Groundwater by Horizontal Recirculation Wells and by Constructed Vertical Flow Wetlands

DTIC Science & Technology

2002-03-01

groundwater laden with contaminants. Once the contaminated water is at the surface, it must be treated for contaminant destruction, generally by...treatment walls only work under very specific hydrogeologic conditions (relatively shallow water table, no seasonal fluctuations in groundwater flow...GCWs Elevation Schematic Water Table Contaminated Groundwater Contaminated Groundwater Treated Groundwater Treated Groundwater Reactive Porous Medium

Eco-toxicity and metal contamination of paddy soil in an e-wastes recycling area.

PubMed

Jun-hui, Zhang; Hang, Min

2009-06-15

Paddy soil samples taken from different sites in an old primitive electronic-waste (e-waste) processing region were examined for eco-toxicity and metal contamination. Using the environmental quality standard for soils (China, Grade II) as reference, soil samples of two sites were weakly contaminated with trace metal, but site G was heavily contaminated with Cd (6.37 mg kg(-1)), and weakly contaminated with Cu (256.36 mg kg(-1)) and Zn (209.85 mg kg(-1)). Zn appeared to be strongly bound in the residual fraction (72.24-77.86%), no matter the soil was metal contaminated or not. However, more than 9% Cd and 16% Cu was present in the non-residual fraction in the metal contaminated soils than in the uncontaminated soil, especially for site G and site F. Compared with that of the control soil, the micronucleus rates of site G and site F soil treatments increased by 2.7-fold and 1.7-fold, respectively. Low germination rates were observed in site C (50%) and site G (50%) soil extraction treated rice seeds. The shortest root length (0.2377 cm) was observed in site G soil treated groups, which is only 37.57% of that of the control soil treated groups. All of the micronucleus ratio of Vicia faba root cells, rice germination rate and root length after treatment of soil extraction indicate the eco-toxicity in site F and G soils although the three indexes are different in sensitivity to soil metal contamination.

Reduce oil and grease content in wastewater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Capps, R.W.; Matelli, G.N.; Bradford, M.L.

Poor water quality is often blamed on biological oxidation unit malfunction. However, poorly treated water entering the bio-unit is more often the problem. At the microscopic level, oil/water-separation dynamics are influenced by pH, fluid velocity, temperature, and unit volumes. Oily water's physical and chemical properties affect pretreatment systems such as API separators, corrugated plate interception (CPI) separators, air flotation and equalization systems. A better understanding of pretreatment systems' limits and efficiencies can improve wastewater quality before it upsets the biological oxidation (BIOX). Oil contamination in refinery wastewater originates from desalting, steam stripping, product treating, tank drains, sample drains and equipmentmore » washdown. The largest volumetric contributors are cooling tower blowdowns and contaminated stormwater. The paper describes the BIOX process; oil/water separation; oil/water emulsions and colloidal solutions; air flotation; surfactants; DAF (dissolved air flotation) process; IAF (induced air flotation) process; equalization; load factors; salts; and system design.« less

Periodic processes in vapor phase biofiltration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moe, W.M.; Irvine, R.L.

1998-07-01

Most industrial processes and environmental remediation activities generate large volumes of air contaminated with low concentrations of volatile organic compounds. Carbon adsorption is the most widely used conventional treatment technology, but it has many drawbacks including secondary waste streams and excessive regeneration costs. Biofiltration, a microbial-based treatment technology, removes and biodegrades contaminants from a wide variety of waste streams without the disadvantages of carbon adsorption. In biofiltration, contaminated air flows through a packed bed containing microorganisms which convert contaminants primarily into carbon dioxide, water, and biomass. This paper describes how periodically operated, controlled unsteady state conditions were imposed on biofiltersmore » which used a new polyurethane foam medium that couples high porosity, suitable pore size, and low density with an ability to sorb water. The potential benefits associated with the controlled, unsteady-state operation of biofilters containing this new polyurethane foam medium are described herein. An example system treating a toluene contaminated waste gas is presented.« less

Green PCB Remediation from Sediment Systems (GPRSS) Project

NASA Technical Reports Server (NTRS)

Falker, John; Thompson, Karen; Zeitlin, Nancy; Quinn, Jacqueline; Parrish, Lewis M.

2014-01-01

An ongoing problem facing the global environment community including NASA centers is the removal and remediation of polychlorinated biphenyls (PCBs). PCBs were commonly used in a variety of materials including paints, caulking, and adhesives due to the advantageous physical and chemical properties that PCBs imparted to these various materials. Unfortunately, these properties have made the treatment of sites contaminated with these chemicals extremely difficult to deal with, due to their inherent chemical stability. The remediation of sediments contaminated with PCBs is especially difficult, primarily due to the risk of releasing the contaminant into the environment during the treatment process. Traditional treatment options involve the use of dredging and incineration of the contaminated soils/sediments, in which the chance of releasing the contaminants is greatly increased. The purpose of this project is to develop cleanup technology capable of remediating contaminated sediments in-situ, with minimum intrusion. This allows for the minimization of any potential contaminant release during the treatment process, providing a safer method for cleanup operations (as opposed to dredging/incineration) and still treating the basic problem of PCB contamination (as opposed to capping).

Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

DOEpatents

Vijayan, S.; Wong, C.F.; Buckley, L.P.

1994-11-22

In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved. 1 fig.

Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

DOEpatents

Vijayan, Sivaraman; Wong, Chi F.; Buckley, Leo P.

1994-01-01

In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved.

Removing inorganics: Common methods have limits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sorg, T.J.

1991-06-01

When EPA sets a regulation (a maximum contaminant level) for a contaminant, it must also specify the best available technology (BAT) that can be used to remove the contaminant. Because the regulations apply to community water systems, the technologies selected are ones that are commonly used to treat community size water systems. Thus, EPA R and D program has focused its efforts on evaluating primarily community applied technologies such as conventional coagulation-filtration, lime softening, ion exchange, adsorption, and membrane process. When BAT is identified for a specific contaminant, frequently the BAT will be listed with its limitations because the processmore » is often not effective under all water quality conditions. The same limitations would also apply to POU/POE treatment. The paper discusses EPA's regulations on inorganic contaminants, the best available technologies cited by EPA, and the limitations of the processes. Using arsenic as an example, the impact of the contaminant chemistry and water quality on removals is presented.« less

Dominierende Prozesse bei der thermischen In-situ-Sanierung (TISS) kontaminierter Geringleiter

NASA Astrophysics Data System (ADS)

Hiester, Uwe; Bieber, Laura

2017-09-01

Contaminants such as chlorinated, aromatic or polycyclic aromatic hydrocarbons (CHC, BTEX, PAH) or mineral oil hydrocarbons (TPH) constitute a prevalent threat to water resources. The significant storage capacity of low permeable soils (aquitards) leads to their long-term contamination. In situ thermal remediation (ISTR) proved to work successfully in treating these soils. Thus, the area of ISTR application grew continuously over the past 10 years. The dominating processes during the remediation can vary considerably, depending on hydrogeological and geological boundary conditions and the contamination itself. This article summarizes the application for in-situ thermal remediation (ISTR) in low permeable soils and aquitards for soil and groundwater treatment. Dominating remediation processes during volatile organic compound (VOC) and residual oil phase recovery are presented. The processes are illustrated by project examples.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lewis, J.C.; Hochreitner, J.J.

Investigations of potential sources of groundwater contamination conducted by various regulatory agencies and consultants at four industrial sites in Logan Township, New Jersey found groundwater contamination at all four sites and at properties adjoining two of the sites. The four sites directly overlie the Potomac-Raritan-Magothy aquifer system, the Township's sole source of potable water. One site was a waste-oil processing and storage facility. The major source of groundwater contamination at the site is a lagoon containing waste oil. Groundwater within 1,000 ft of the lagoon is contaminated. The second site is used to maintain, dispatch, and clean chemical-transportation tanks. Potentialmore » sources of groundwater contamination at the site include former wastewater lagoons, leaking storage drums, and leaking tank trucks. Groundwater at and immediately north of the property is contaminated. Organic compounds are manufactured at the third site. Potential sources of groundwater contamination at this site include landfilled industrial wastes. Groundwater underlying the property is contaminated, but there is no evidence of offsite groundwater contamination from this source. The fourth site is used to treat and dispose of hazardous wastes. The major source of groundwater contamination at this site is landfilled residue from waste-treatment processes. Groundwater underlying the property is contaminated, but there is no evidence of off-site groundwater contamination from this source.« less

The Impact of Thermal Remediation on Soil Rehabilitation

NASA Astrophysics Data System (ADS)

Pape, Andrew; Switzer, Christine; Knapp, Charles

2013-04-01

In an effort to restore the social and economic value of brownfield sites contaminated by hazardous organic liquids, many new remediation techniques involving the use of elevated temperatures to desorb and extract or destroy these contaminants have been developed. These approaches are typically applied to heavily contaminated soils to effect substantial source removal from the subsurface. These processes operate over a range of temperatures from just above ambient to in excess of 1000˚C depending on technology choice and contaminant type. To facilitate the successful rehabilitation of treated soils for agriculture, biomass production, or habitat enrichment the effects of high temperatures on the ability of soil to support biological activity needs to be understood. Four soils were treated with high temperatures or artificially contaminated and subjected to a smouldering treatment (600-1100°C) in this investigation. Subsequent chemical analysis, plant growth trials and microbial analysis were used to characterise the impacts of these processes on soil geochemistry, plant health, and potential for recovery. Decreases were found in levels of carbon (>250˚C), nitrogen (>500˚C) and phosphorus (1000˚C) with intermediate temperatures having variable affects on bio-available levels. Macro and micro nutrients such as potassium, calcium, zinc and copper also showed changes with general trends towards reduced bioavailability at higher temperatures. Above 500°C, cation exchange capacity and phosphate adsorption were lowered indicating that nutrient retention will be a problem in some treated soils. In addition, these temperatures reduced the content of clay sized particles changing the texture of the soils. These changes had a statistically significant impact on plant growth with moderate growth reductions occurring at 250°C and 500°C. Above 750°C, growth was extremely limited and soils treated at these temperatures would need major restorative efforts. Microbial re-colonisation and activity were inhibited in soils treated above 500°C due to the lack of available carbon sources. Early experiments with organic amendments and green manures show promise in facilitating more rapid recolonisation. These results underscore the importance of considering long-term soil recovery as part of the remediation strategy.

Fate of virginiamycin through the fuel ethanol production process

USDA-ARS?s Scientific Manuscript database

Antibiotics are frequently used to prevent and treat bacterial contamination of commercial fuel ethanol fermentations, but there is concern that antibiotic residues may persist in the distillers grains coproducts. A study to evaluate the fate of virginiamycin during the ethanol production process wa...

40 CFR 437.2 - General definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... any facility that treats (for disposal, recycling or recovery of material) any hazardous or non... a facility. (o) Oily absorbent recycling means the process of recycling oil-soaked or contaminated... stock for lubricants or other petroleum products. (y) Recovery means the recycling or processing of a...

40 CFR 437.2 - General definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... any facility that treats (for disposal, recycling or recovery of material) any hazardous or non... a facility. (o) Oily absorbent recycling means the process of recycling oil-soaked or contaminated... stock for lubricants or other petroleum products. (y) Recovery means the recycling or processing of a...

Treatment options for low-level radiologically contaminated ORNL filtercake

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Hom-Ti; Bostick, W.D.

1996-04-01

Water softening sludge (>4000 stored low level contaminated drums; 600 drums per year) generated by the ORNL Process Waste Treatment Plant must be treated, stabilized, and placed in safe storage/disposal. The sludge is primarily CaCO{sub 3} and is contaminated by low levels of {sup 90}Sr and {sup 137}Cs. In this study, microwave sintering and calcination were evaluated for treating the sludge. The microwave melting experiments showed promise: volume reductions were significant (3-5X), and the waste form was durable with glass additives (LiOH, fly ash). A commercial vendor using surrogate has demonstrated a melt mineralization process that yields a dense monolithicmore » waste form with a volume reduction factor (VR) of 7.7. Calcination of the sludge at 850-900 C yielded a VR of 2.5. Compaction at 4500 psi increased the VR to 4.2, but the compressed form is not dimensionally stable. Addition of paraffin helped consolidate fines and yielded a VR of 3.5. In conclusion, microwave melting or another form of vitrification is likely to be the best method; however for immediate implementation, the calculation/compaction/waxing process is viable.« less

Bacteriophages as indicators of human and animal faecal contamination in raw and treated wastewaters from Tunisia.

PubMed

Yahya, M; Hmaied, F; Jebri, S; Jofre, J; Hamdi, M

2015-05-01

We aimed at quantifying bacteriophages in raw and treated wastewaters of human and animal origin in Tunisia to assess their usefulness for tracking the origin of faecal pollution and in the follow-up of effectiveness of water treatments process. The concentrations of bacteriophages in wastewater samples were determined by double layer agar technique. Somatic coliphages and F-specific RNA bacteriophages were present in all types of samples in high concentrations. The values of Escherichia coli were variable depending on geographical location. On the other hand, bacteriophages infecting strain GA17 were detected preferably when human faecal contamination was occurred. Bacteriophages appear as a feasible and widely applicable manner to detect faecal contamination in Tunisia. On the other hand, phages infecting GA17 could be good markers for tracking the origin of faecal pollution in the area studied. The reuse of treated wastewaters can be a solution to meet the needs of water in the geographical area of study. Bacteriophages seem to predict differently the presence of faecal contamination in water than bacterial indicators. Consequently, they can be a valuable additional tool to improve water resources management for minimizing health risks. © 2015 The Society for Applied Microbiology.

Method of treating waste water

DOEpatents

Deininger, James P.; Chatfield, Linda K.

1995-01-01

A process of treating water to remove metal ion contaminants contained therein, said metal ion contaminants selected from the group consisting of metals in Groups 8, 1b, 2b, 4a, 5a, or 6a of the periodic table, lanthanide metals, and actinide metals including transuranic element metals, by adjusting the pH of a metal ion contaminant-containing water source to within the range of about 6.5 to about 14.0, admixing the water source with a mixture of an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, in an amount sufficient to form a precipitate within the water source, the amount the mixture of ferrate and water soluble salt effective to reduce the metal ion contaminant concentration in the water source, permitting the precipitate in the admixture to separate and thereby yield a supernatant liquid having a reduced metal ion contaminant concentration, and separating the supernatant liquid having the reduced metal ion contaminant concentration from the admixture is provided. A composition of matter including an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, is also provided.

An overview of permeable reactive barriers for in situ sustainable groundwater remediation.

PubMed

Obiri-Nyarko, Franklin; Grajales-Mesa, S Johana; Malina, Grzegorz

2014-09-01

Permeable reactive barriers (PRBs) are one of the innovative technologies widely accepted as an alternative to the 'pump and treat' (P&T) for sustainable in situ remediation of contaminated groundwater. The concept of the technology involves the emplacement of a permeable barrier containing reactive materials across the flow path of the contaminated groundwater to intercept and treat the contaminants as the plume flows through it under the influence of the natural hydraulic gradient. Since the invention of PRBs in the early 1990s, a variety of materials has been employed to remove contaminants including heavy metals, chlorinated solvents, aromatic hydrocarbons, and pesticides. Contaminant removal is usually accomplished via processes such as adsorption, precipitation, denitrification and biodegradation. Despite wide acknowledgment, there are still unresolved issues about long term-performance of PRBs, which have somewhat affected their acceptability and full-scale implementation. The current paper presents an overview of the PRB technology, which includes the state of art, the merits and limitations, the reactive media used so far, and the mechanisms employed to transform or immobilize contaminants. The paper also looks at the design, construction and the long-term performance of PRBs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cleaning Processes across NASA Centers

NASA Technical Reports Server (NTRS)

Hammond, John M.

2010-01-01

All significant surfaces of the hardware must be pre-cleaned to remove dirt, grit, scale, corrosion, grease, oil and other foreign matter prior to any final precision cleaning process. Metallic parts shall be surface treated (cleaned, passivated, pickled and/or coated) as necessary to prevent latent corrosion and contamination.

Superfund Record of Decision (EPA Region 2): Garden State Cleaners, Buena Borough, Atlantic County, NJ. (First remedial action), September 1991. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-09-26

The 3,000-square-foot Garden State Cleaners (GSC) site is an active dry cleaning operation in Minotola, Bueno Borough, Atlantic County, New Jersey. Land use in the area is residential and commercial, and local residents obtain drinking water from the Borough municipal water supply system. From 1966 to the present, dry cleaning activities using PCE were conducted at the GSC site, and until 1985, wastes were discharged through pipes directly into the ground. In 1984, State investigations showed elevated levels of PCE in ground water adjacent to and downgradient from the GSC and SJCC facilities, and elevated levels of PCE and TCEmore » in onsite soil. The selected remedial action for the site includes treating onsite approximately 1,600 cubic yards of contaminated soil using in-situ vapor extraction; treating the contaminated wastewater from the vapor extraction processes onsite using an air stripping column; treating air emissions using carbon adsorption units; pumping and onsite treatment of contaminated ground water using air stripping and carbon adsorption; reinjecting the treated ground water upgradient from the site; regenerating spent activated carbon from both treatment processes offsite; conducting long-term ground water monitoring; and implementing temporary institutional controls. The estimated present worth cost for the remedial action at the GSC site is $5,451,000, which includes an estimated annual O and M cost of $249,500 for 70 years.« less

Development of a Groundwater Transport Simulation Tool for Remedial Process Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivarson, Kristine A.; Hanson, James P.; Tonkin, M.

2015-01-14

The groundwater remedy for hexavalent chromium at the Hanford Site includes operation of five large pump-and-treat systems along the Columbia River. The systems at the 100-HR-3 and 100-KR-4 groundwater operable units treat a total of about 9,840 liters per minute (2,600 gallons per minute) of groundwater to remove hexavalent chromium, and cover an area of nearly 26 square kilometers (10 square miles). The pump-and-treat systems result in large scale manipulation of groundwater flow direction, velocities, and most importantly, the contaminant plumes. Tracking of the plumes and predicting needed system modifications is part of the remedial process optimization, and is amore » continual process with the goal of reducing costs and shortening the timeframe to achieve the cleanup goals. While most of the initial system evaluations are conducted by assessing performance (e.g., reduction in contaminant concentration in groundwater and changes in inferred plume size), changes to the well field are often recommended. To determine the placement for new wells, well realignments, and modifications to pumping rates, it is important to be able to predict resultant plume changes. In smaller systems, it may be effective to make small scale changes periodically and adjust modifications based on groundwater monitoring results. Due to the expansive nature of the remediation systems at Hanford, however, additional tools were needed to predict the plume reactions to system changes. A computer simulation tool was developed to support pumping rate recommendations for optimization of large pump-and-treat groundwater remedy systems. This tool, called the Pumping Optimization Model, or POM, is based on a 1-layer derivation of a multi-layer contaminant transport model using MODFLOW and MT3D.« less

Effects of ammoniation on the 'carry-over' of aflatoxins into bovine milk.

PubMed

Fremy, J M; Gautier, J P; Herry, M P; Terrier, C; Calet, C

1988-01-01

Two experiments were performed using lactating cows fed various treated and non-treated commodities from AFB1 contaminated peanut cakes. Treatment with ammonia gas by an autoclaving process was used for detoxification. Two methods were used for AFM1 determination in every milk sample: a TLC procedure recognized by AOAC and IDF and an HPLC method with a detection limit of 0.100 and 0.010 microgram/l, respectively. In a first experiment, lactating cows were fed treated and untreated meals during periods separated by uncontaminated soya meals phases. The total excreted AFM1 was 2.6% of the total ingested AFB1 from untreated feed contaminated at 1100 micrograms/kg. During periods receiving treated meals in the diet, AFM1 contents in milk were below 0.1 microgram/l. However, by using AFM1 data obtained using the HPLC method, an AFM1/AFB1 ratio of 4.6% was found from treated feed contaminated at 40 micrograms AFB1/kg. In a second experiment, a herd of 50 lactating cows was used for a long term (16 months) feeding of mixed commodities containing 30% ammoniated peanut cakes. AFB1 residues in the treated diet were below 10 micrograms/kg, the EEC action level, and no AFM1 residue was found up to 0.1 microgram/l in collected milk throughout this experiment.

Electrolyte selection and microbial toxicity for electrochemical oxidative water treatment using a boron-doped diamond anode to support site specific contamination incident response.

PubMed

Phillips, Rebecca B; James, Ryan R; Magnuson, Matthew L

2018-04-01

Intentional and unintentional contamination incidents, such as terrorist attacks, natural disasters, and accidental spills, can result in large volumes of contaminated water. These waters may require pre-treatment before disposal and assurances that treated waters will not adversely impact biological processes at wastewater treatment facilities, or receiving waters. Based on recommendations of an industrial workgroup, this study addresses such concerns by studying electrochemical advanced oxidation process (EAOP) pre-treatment for contaminated waters, using a boron-doped diamond (BDD) anode, prior to discharge to wastewater treatment facilities. Reaction conditions were investigated, and microbial toxicity was assessed using the Microtox ® toxicity assay and the Nitrification Inhibition test. A range of contaminants were studied including herbicides, pesticides, pharmaceuticals and flame retardants. Resulting toxicities varied with supporting electrolyte from 5% to 92%, often increasing, indicating that microbial toxicity, in addition to parent compound degradation, should be monitored during treatment. These toxicity results are particularly novel because they systematically compare the microbial toxicity effects of a variety of supporting electrolytes, indicating some electrolytes may not be appropriate in certain applications. Further, these results are the first known report of the use of the Nitrification Inhibition test for this application. Overall, these results systematically demonstrate that anodic oxidation using the BDD anode is useful for addressing water contaminated with refractory organic contaminants, while minimizing impacts to wastewater plants or receiving waters accepting EAOP-treated effluent. The results of this study indicate nitrate can be a suitable electrolyte for incident response and, more importantly, serve as a baseline for site specific EAOP usage. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of temperature on the release of hexadecane from soil by thermal treatment.

PubMed

Merino, Jerónimo; Bucalá, Verónica

2007-05-08

A natural organic soil (2.5% of total organic carbon) was artificially contaminated with hexadecane, and thermally treated under an inert medium up to different final temperatures (150-800 degrees C) for 30 min to simulate ex situ thermal process conditions. The experiments were conducted using a complete organic soil, instead of the clays or isolated soil fractions that are commonly used. Neat and contaminated samples were separately heated to understand the impact of the soil itself and the contaminant in the release of volatiles. The soil quality as well as the quality and amount of volatile compounds generated during the process were monitored. More than 80-88% of the initial hexadecane content in the soil matrix was recovered in liquids traps after the thermal treatment, therefore the contaminant could be recovered for further recycling. The high amount of hexadecane collected without suffering chemical transformations indicated that the main mechanism for the hexadecane removal was evaporation. The analysis of the light gases released from contaminated samples indicated negligible or null hexadecane pyrolysis reaction rates, confirming that the evaporation/desorption of the contaminant are the processes that governed the removal of the contaminant from the soil. For the soil tested, of a relatively low surface area, good removal efficiencies (higher than 99.9%) were detected at about 300 degrees C, being higher temperatures not necessary to significantly improve the contamination removal.

Application of bacteriophages to reduce Salmonella contamination on workers' boots in rendering-processing environment.

PubMed

Gong, C; Jiang, X; Wang, J

2017-10-01

Workers' boots are considered one of the re-contamination routes of Salmonella for rendered meals in the rendering-processing environment. This study was conducted to evaluate the efficacy of a bacteriophage cocktail for reducing Salmonella on workers' boots and ultimately for preventing Salmonella re-contamination of rendered meals. Under laboratory conditions, biofilms of Salmonella Typhimurium avirulent strain 8243 formed on rubber templates or boots were treated with a bacteriophage cocktail of 6 strains (ca. 9 log PFU/mL) for 6 h at room temperature. Bacteriophage treatments combined with sodium hypochlorite (400 ppm) or 30-second brush scrubbing also were investigated for a synergistic effect on reducing Salmonella biofilms. Sodium magnesium (SM) buffer and sodium hypochlorite (400 ppm) were used as controls. To reduce indigenous Salmonella on workers' boots, a field study was conducted to apply a bacteriophage cocktail and other combined treatments 3 times within one wk in a rendering-processing environment. Prior to and after bacteriophage treatments, Salmonella populations on the soles of rubber boots were swabbed and enumerated on XLT-4, Miller-Mallinson or CHROMagar™ plates. Under laboratory conditions, Salmonella biofilms formed on rubber templates and boots were reduced by 95.1 to 99.999% and 91.5 to 99.2%, respectively. In a rendering-processing environment (ave. temperature: 19.3°C; ave. relative humidity: 48%), indigenous Salmonella populations on workers' boots were reduced by 84.2, 92.9, and 93.2% after being treated with bacteriophages alone, bacteriophages + sodium hypochlorite, and bacteriophages + scrubbing for one wk, respectively. Our results demonstrated the effectiveness of bacteriophage treatments in reducing Salmonella contamination on the boots in both laboratory and the rendering-processing environment. © 2017 Poultry Science Association Inc.

Method for treatment of soils contaminated with organic pollutants

DOEpatents

Wickramanayake, Godage B.

1993-01-01

A method for treating soil contaminated by organic compounds wherein an ozone containing gas is treated with acid to increase the stability of the ozone in the soil environment and the treated ozone applied to the contaminated soil to decompose the organic compounds. The soil may be treated in situ or may be removed for treatment and refilled.

Superfund Record of Decision (EPA Region 6): Texarkana Wood Preserving Company, Texarkana, Bowie County, TX. (First remedial action), September 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The 25-acre Texarkana Wood Preserving site is a former wood treating facility in Bowie County, Texas, within the Days Creek 100-year floodplain. Surrounding land use is industrial, residential, and agricultural. Since the early 1900s, several lumber-related businesses have operated at the site, with documented creosote-based wood treating operations starting in 1954. By 1971, Texarkana was also using creosote and pentachlorophenol for wood preserving. State investigations of the site between 1968 and 1984, showed Texarkana to be negligent or delinquent in fulfilling various permit requirements. The Record of Decision (ROD) addresses onsite contaminated soil near the processing ponds and contaminated groundmore » water in a shallow aquifer. The primary contaminants of concern affecting the soil, sediment, sludge, and ground water are organics including dioxin, PAHs, pesticides, and phenols.« less

Wastewater treatment in the pulp-and-paper industry: A review of treatment processes and the associated greenhouse gas emission.

PubMed

Ashrafi, Omid; Yerushalmi, Laleh; Haghighat, Fariborz

2015-08-01

Pulp-and-paper mills produce various types of contaminants and a significant amount of wastewater depending on the type of processes used in the plant. Since the generated wastewaters can be potentially polluting and very dangerous, they should be treated in wastewater treatment plants before being released to the environment. This paper reviews different wastewater treatment processes used in the pulp-and-paper industry and compares them with respect to their contaminant removal efficiencies and the extent of greenhouse gas (GHG) emission. It also evaluates the impact of operating parameters on the performance of different treatment processes. Two mathematical models were used to estimate GHG emission in common biological treatment processes used in the pulp-and-paper industry. Nutrient removal processes and sludge treatment are discussed and their associated GHG emissions are calculated. Although both aerobic and anaerobic biological processes are appropriate for wastewater treatment, their combination known as hybrid processes showed a better contaminant removal capacity at higher efficiencies under optimized operating conditions with reduced GHG emission and energy costs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Scrubbing of contaminants from contaminated air streams with aerogel materials with optional photocatalytic destruction

DOEpatents

Attia, Yosry A.

2000-01-01

Disclosed is a method for separating a vaporous or gaseous contaminant from an air stream contaminated therewith. This method includes the steps of: (a) passing said contaminated air into a contact zone in which is disposed an aerogel material capable of selecting adsorbing said contaminant from air and therein contacting said contaminated air with an aerogel material; and (b) withdrawing from said zone, air depleted of said contaminant. For present purposes, "contaminant" means a material not naturally occurring in ambient air and/or a material naturally occurring in air but present at a concentration above that found in ambient air. Thus, the present invention scrubs (or treats) air for the purpose of returning it to its ambient composition. Also disclosed herein is a process for the photocatalytic destruction of contaminants from an air stream wherein the contaminated air stream is passed into a control cell or contact zone in which is disposed a photocatalytic aerogel and exposing said aerogel to ultraviolet (UV) radiation for photocatalytically destroying the adsorbed contaminant, and withdrawing from said cell an exhaust air stream depleted in said contaminant.

TREATING CHLORINATED WASTES WITH THE KPEG PROCESS

EPA Science Inventory

The two reports summarized here describe development of the alkali metal (polyethylene gylycolate (APEG) chemical technology to dechlorinate hazardous hydrocarbons in soils and its application at four demonstration sites: field-scale application to contaminated soils on the isla...

Changes in spectral signatures of red lettuce regards to Zinc uptake

NASA Astrophysics Data System (ADS)

Shin, J.; Yu, J.; Koh, S. M.; Park, G.; Kim, S.

2017-12-01

Heavy metal contaminations caused by human activities such as mining and industrial activities caused serious soil contamination. Soil contaminations causes secondary impact on vegetation by uptake processes. Intakes of vegetables harvested from heavy metal contaminated soil may cause serious health problems. It would be very effective if screening tool could be developed before the vegetables are distributed over the market. This study investigated spectral response of red lettuce regards to Zn uptake from the treated soil in a laboratory condition. Zn solutions at different levels of concentration are injected to potted lettuce. The chemical composition and spectral characteristics of the leaves are analyzed every 2 days and the correlation between the Zn concentration and spectral reflectance is investigated. The experiment reveals that Zn uptake of red lettuce is significantly higher for the leaves from treated pot compared to untreated pot showing highly contaminated concentrations beyond the standard Zn concentrations for food. The spectral response regards to Zn is manifested at certain level of concentration threshold. Below the threshold, reflectance at NIR regions increases regards to increase in Zn concentration. On the other hand, above the threshold, IR reflectance decreases and slope of NIR shoulder increases regards to higher Zn concentration. We think this result may contribute for development of screening tools for heavy metal contaminations in vegetables.

Movement and fate of solutes in a plume of sewage-contaminated ground water, Cape Cod, Massachusetts

USGS Publications Warehouse

LeBlanc, D. R.

1984-01-01

The U.S. Geological Survey (USGS) has begun a nationwide program to study the fate of toxic wastes in groundwater. Several sites where groundwater is known to be contaminated are being studied by interdisciplinary teams of geohydrologists, chemists, and microbiologists. The objective of these studies is to obtain a thorough quantitative understanding of the physical, chemical, and biological processes of contaminant generation, migration, and attenuation in aquifers. One of the sites being studied by the USGS under this program is a plume of sewage contaminated groundwater on Cape Cod, Massachusetts. The plume was formed by land disposal of treated sewage to a glacial outwash aquifer since 1936. This report summarizes results obtained during the first year of research at the Cape Cod s under the USGS Toxic-Waste Ground-Water Contamination Program. The seven papers included in this volume were presented at the Toxic Waste Technical Meeting, Tucson, Arizona, in March 1984. They provide an integrated view of the subsurface distribution of contaminants based on the first year of research and discuss hypotheses concerning the transport processes that affect the movement of contaminants in the plume. (See W89-09053 thru W89-09059) (Lantz-PTT)

Process for gamma ray induced degradation of polychlorinated biphenyls

DOEpatents

Meikrantz, David H.; Mincher, Bruce J.; Arbon, Rodney E.

1998-01-01

The invention is a process for the in-situ destruction of polychlorinated biphenyl (PCB) compounds in transformer oils and transformers. These compounds are broken down selectively by irradiation of the object or mixture using spent nuclear fuel or any isotopic source of high energy gamma radiation. For example, the level of applied dose required to decompose 400 ppm of polychlorinated biphenyl in transformer oil to less than 50 ppm is 500 kilogray. Destruction of polychlorinated biphenyls to levels of less than 50 ppm renders the transformer oil or transformer non-PCB contaminated under current regulations. Therefore, this process can be used to treat PCB contaminated oil and equipment to minimize or eliminate the generation of PCB hazardous waste.

RECOVERY OF VOCS FROM SURFACTANT SOLUTION BY PERVAPORATION

EPA Science Inventory

Surfactant-based processes are emerging as promising technologies to enhance conventional pump-and-treat methods for remediating soils contaminated with nonaqueous phase liquids (NAPLs), primarily due to the potential to significantly reduce the remediation time. In order to reus...

APPLICATION OF THERMAL DESORPTION TECHNOLOGIES TO HAZARDOUS WASTE SITES

EPA Science Inventory

Thermal desorption is a separation process frequently used to remediate many Superfund sites. Thermal desorption technologies are recommended and used because of (1) the wide range of organic contaminants effectively treated, (2) availability and mobility of commercial systems, ...

Reaching Your Limits.

ERIC Educational Resources Information Center

Science Activities, 1995

1995-01-01

Presents a Project WET water education activity. By attempting to remove contaminants from "wastewater," students gain an appreciation for what is involved in providing clean drinking water. Students describe the process for treating wastewater and become familiar with nontoxic household cleaning methods. (LZ)

DEMONSTRATION BULLETIN: AQUADETOX®/ SVE SYSTEM and AWD Technologies, Inc.

EPA Science Inventory

The AWD technology simultaneously treats groundwater and soil-gas contaminated with volatile or ganic compounds (VOC), such as trichloroethylene (TCE) and tetrachloroethylene (PCE). This technology integrates two processes: (1) AquaDetox®, a moderate vacuum (pressure about 50 ...

Superfund record of decision (EPA Region 4): T H Agriculture and Nutrition Site, Dougherty County, Albany, GA, April 26, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This decision document (Record of Decision), presents the selected Remedial Action for the Operable Unit Two for the T H Agriculture & Nutrition (THAN) Site, Albany, Georgia. The second operable unit addresses the source of the contamination on the eastern parcel of the Site. The major components of the selected remedy for operable unit two include: the excavation of all soil contaminated with organics necessary to meet performance standards; the staging and preconditioning of soil for low temperature thermal desorption treatment; the treatment of excavated soil by low temperature thermal desorption; the placement of treated, decontaminated soil back to themore » site; periodic sampling of treated soil during the treatment process to verify the effectiveness of the remedy; air monitoring to ensure safety of nearby residents and workers; groundwater monitoring to ensure that metals contaminated remaining in the subsurface soil will not result in contaminated groundwater migrating offsite in concentrations which exceed groundwater protection standards; and deed restrictions to prevent residential use of the property.« less

Removal of petroleum hydrocarbons from contaminated groundwater by the combined technique of adsorption onto perlite followed by the O3/H2O2 process.

PubMed

Moussavi, Gholamreza; Bagheri, Amir

2012-09-01

Groundwater contaminated with petroleum hydrocarbons was treated using a combined system of adsorption onto powdered expanded perlite (PEP) followed by the O3/H2O2 process. The pretreatment investigations indicated a high capacity for PEP to remove petroleum hydrocarbons from the contaminated water. An experimental total petroleum hydrocarbon (TPH) adsorption capacity of 275 mg/g PEP was obtained at the natural pH of water. The experimental data fit best with the Freundlich isotherm model and pseudo-second-order adsorption model. The second phase of the experiment evaluated the performance of the O3/H2O2 process in the removal of residual TPH from pretreated water and compared the results with that of raw water. The O3/H202 process attained a maximum TPH removal rate for the pretreated water after 70 min, when 93% of the residual TPH in the effluent of the adsorption system was removed. Overall, the combination of adsorption onto PEP for 100 min and the subsequent treatment with the O3/H2O2 process for 70min eliminated over 99% of the TPH of highly petroleum-contaminated groundwater, with initial values of 162 mg/L. Therefore, we can conclude that the developed treatment system is an appropriate method of remediation for petroleum-contaminated waters.

Clean amine solvents economically and online

DOE Office of Scientific and Technical Information (OSTI.GOV)

Price, J.; Burns, D.

1995-08-01

Using electrodialysis technology to clean amine solvents is economically competitive with traditional change-out or ``bleed and feed`` methods, even for small systems, because a unit shutdown is not necessary to perform the process. Electrodialysis also has advantages over other online cleanup processes like ion exchange and vacuum reclamation. Off gases and olefinic and saturate liquefied petroleum gas (LPG) streams generated during operation of fluid catalytic crackers (FCC), cokers and other refinery processing equipment must be treated to remove undesirable components like hydrogen sulfide and carbon dioxide before they can be sold or used in downstream processes. At an Arkansas City,more » Kansas, refinery, a classic amine-based chemical absorbent system is used for this purpose. It comprises two absorbing contacts for gas and two for liquids. The system is charged with an N-methyldiethanolamine (MDEA)-based product that selectively absorbs contaminants. Amine is regenerated by removing contaminants with steam stripping. Lean amine is then recirculated to the absorbers. This case history demonstrates the effectiveness of electrodialysis technology for contaminant removal.« less

Degradation of TATP, TNT, and RDX using mechanically alloyed metals

NASA Technical Reports Server (NTRS)

Geiger, Cherie (Inventor); Sigman, Michael (Inventor); Fidler, Rebecca (Inventor); Clausen, Christian (Inventor)

2012-01-01

Bimetallic alloys prepared in a ball milling process, such as iron nickel (FeNi), iron palladium (FePd), and magnesium palladium (MgPd) provide in situ catalyst system for remediating and degrading nitro explosive compounds. Specifically, munitions, such as, 2,4,6-trinitrotoluene (TNT), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), nitrocellulose and nitroglycerine that have become contaminants in groundwater, soil, and other structures are treated on site to remediate explosive contamination.

Leaching of arsenic, copper and chromium from thermally treated soil.

PubMed

Kumpiene, Jurate; Nordmark, Désirée; Hamberg, Roger; Carabante, Ivan; Simanavičienė, Rūta; Aksamitauskas, Vladislovas Česlovas

2016-12-01

Thermal treatment, if properly performed, is an effective way of destroying organic compounds in contaminated soil, while impact on co-present inorganic contaminants varies depending on the element. Leaching of trace elements in thermally treated soil can be altered by co-combusting different types of materials. This study aimed at assessing changes in mobility of As, Cr and Cu in thermally treated soil as affected by addition of industrial by-products prior to soil combustion. Contaminated soil was mixed with either waste of gypsum boards, a steel processing residue (Fe 3 O 4 ), fly ash from wood and coal combustion or a steel abrasive (96.5% Fe 0 ). The mixes and unamended soil were thermally treated at 800 °C and divided into a fine fraction <0.125 mm and a coarse fraction >0.125 mm to simulate particle separation occurring in thermal treatment plants. The impact of the treatment on element behaviour was assessed by a batch leaching test, X-ray absorption spectroscopy and dispersive X-ray spectrometry. The results suggest that thermal treatment is highly unfavourable for As contaminated soils as it increased both the As leaching in the fine particle size fraction and the mass of the fines (up to 92%). Soil amendment with Fe-containing compounds prior to the thermal treatment reduced As leaching to the levels acceptable for hazardous waste landfills, but only in the coarse fraction, which does not justify the usefulness of such treatment. Among the amendments used, gypsum most effectively reduced leaching of Cr and Cu in thermally treated soil and could be recommended for soils that do not contain As. Fly ash was the least effective amendment as it increased leaching of both Cr and As in majority of samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

ACCUMULATION RATE OF MICROBIAL BIOMASS AT TWO PERMEABLE REACTIVE BARRIER SITES

EPA Science Inventory

Accumulation of mineral precipitates and microbial biomass are key factors that impact the long-term performance of in-situ Permeable Reactive Barriers for treating contaminated groundwater. Both processes can impact remedial performance by decreasing zero-valent iron reactivity...

Radio frequency heating for in-situ remediation of DNAPL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasevich, R.S.

1996-08-01

In-situ radio frequency (RF) heating technology for treating soils contaminated with dense nonaqueous phase liquids (DNAPLs) is described. RF imparts heat to non-conducting materials through the application of carefully controlled RF transmissions, improving contaminant flow characteristics and facilitating separation and removal from subsurface soils. The paper outlines advantages and limitations of RF remediation, process operations, general technology considerations, low permeability media considerations, commercial availability, and costs. Two case histories of RF remediation are briefly summarized. 13 refs., 10 figs.

Soil recycling paves the way for treating brownfields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gladdys, R.

A soil recycling and stabilization process allows once-contaminated soil to be incorporated into paving materials. Contaminated soils is more widespread than often realized, with one of the more common sources being petroleum products such as fuel oil and gasoline. Until recently, the conventional solution was to have the material excavated, separated from remining soil and trucked to a hazardous waste landfill. This article describes an alternative approach under the following topics: move the solution, not the problem; on site recycling; heavy metals stabilization; economics.

Oxidation of contaminative methane traces with radio-frequency discharge

NASA Technical Reports Server (NTRS)

Flamm, D. L.; Wydeven, T. L.

1976-01-01

An 11.8 MHz glow discharge was used to oxidize trace levels of methane in oxygen. The concentration of methane can be reduced by three orders of magnitude. The effects of power (0-400 W), flow rate (10-1000 cc-STP/min) and concentration (70-8000 ppm) were investigated at pressures ranging from 50 torr to almost 1 atm. No organic reaction products were detected in the treated gas stream. The process may prove useful for the removal of atmospheric trace contaminants at ambient pressure.

Application of the base catalyzed decomposition process to treatment of PCB-contaminated insulation and other materials associated with US Navy vessels. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidt, A.J.; Zacher, A.H.; Gano, S.R.

1996-09-01

The BCD process was applied to dechlorination of two types of PCB-contaminated materials generated from Navy vessel decommissioning activities at Puget Sound Naval Shipyard: insulation of wool felt impregnated with PCB, and PCB-containing paint chips/debris from removal of paint from metal surfaces. The BCD process is a two-stage, low-temperature chemical dehalogenation process. In Stage 1, the materials are mixed with sodium bicarbonate and heated to 350 C. The volatilized halogenated contaminants (eg, PCBs, dioxins, furans), which are collected in a small volume of particulates and granular activated carbon, are decomposed by the liquid-phase reaction (Stage 2) in a stirred-tank reactor,more » using a high-boiling-point hydrocarbon oil as the reaction medium, with addition of a hydrogen donor, a base (NaOH), and a catalyst. The tests showed that treating wool felt insulation and paint chip wastes with Stage 2 on a large scale is feasible, but compared with current disposal costs for PCB-contaminated materials, using Stage 2 would not be economical at this time. For paint chips generated from shot/sand blasting, the solid-phase BCD process (Stage 1) should be considered, if paint removal activities are accelerated in the future.« less

MOLECULAR BONDING SYSTEM - INNOVATIVE TECHNOLOGY EVALUATION REPORT

EPA Science Inventory

This document presents an evaluation of the Molecular Bonding System (MBS) and its ability to chemically stabilize three metals-contaminated wstes/soils during a SITe demo. The MBS process treated approximately 500 tons each of soil/Fill, Slag, and Miscellaneous Smelter Waste wit...

DEMONSTRATION BULLETIN: TERRA KLEEN SOLVENT EXTRACTION TECHNOLOGY - TERRA-KLEEN RESPONSE GROUP, INC.

EPA Science Inventory

The Terra-Kleen Solvent Extraction Technology was developed by Terra-Kleen Response Group, Inc., to remove polychlorinated biphenyls (PCB) and other organic constituents from contaminated soil. This batch process system uses a proprietary solvent at ambient temperatures to treat ...

Removal of emerging contaminants in sewage water subjected to advanced oxidation with ozone.

PubMed

Ibáñez, M; Gracia-Lor, E; Bijlsma, L; Morales, E; Pastor, L; Hernández, F

2013-09-15

Advanced oxidation processes (AOP) based on ozone treatments, assisted by ultrasounds, have been investigated at a pilot-plant scale in order to evaluate the removal of emerging contaminants in sewage water. Around 60 emerging contaminants, mainly pharmaceuticals from different therapeutically classes and drugs of abuse, have been determined in urban wastewater samples (treated and untreated) by LC-MS/MS. In a first step, the removal efficiency of these contaminants in conventional sewage water treatment plants was evaluated. Our results indicate that most of the compounds were totally or partially removed during the treatment process of influent wastewater. Up to 30 contaminants were quantified in the influent and effluent samples analysed, being antibiotics, anti-inflammatories, cholesterol lowering statin drugs and angiotensin II receptor antagonists the most frequently detected. Regarding drugs of abuse, cocaine and its metabolite benzoylecgonine were the most frequent. In a second step, the effectiveness of AOP in the removal of emerging contaminants remaining in the effluent was evaluated. Ozone treatments have been proven to be highly efficient in the removal, notably decreasing the concentrations for most of the emerging contaminants present in the water samples. The use of ultrasounds, alone or assisting ozone treatments, has been shown less effective, being practically unnecessary. Copyright © 2013 Elsevier B.V. All rights reserved.

Full scale remediation of an explosives-contaminated site at Yorktown Naval Weapons Station using the SABRE{trademark} process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaake, R.H.; Bono, J.; Yergovich, T.

Characterization of a former weapons loading and assembly facility identified soil contaminated with the explosives TNT (2,4,6-trinitrotoluene) and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine). The site contains of a variety of discrete soil types that include clay, sand, and humus. A portion of the site is also periodically submerged due to tidal action. Treatability studies were performed in conjunction with the Army Corps of Engineers Waterways Experiment Station. Studies indicated the SABRE Process could successfully treat the soil to the specified treatment goals. A full scale demonstration of the Simplot Anaerobic Biological Remediation (SABRE{trademark}) Process was carried out at the Yorktown, Virginia Naval Weaponsmore » Station. Over 650 yd{sup 3} of soil was treated to less than 2.5 mg/kg TNT in approximately 30 days. Initial concentrations were estimated to be 450 mg/kg. The soil was screened and placed into an in-ground, double-lined biocell using a soil fluidizing system.« less

Process for gamma ray induced degradation of polychlorinated biphenyls

DOEpatents

Meikrantz, D.H.; Mincher, B.J.; Arbon, R.E.

1998-08-25

The invention is a process for the in-situ destruction of polychlorinated biphenyl (PCB) compounds in transformer oils and transformers. These compounds are broken down selectively by irradiation of the object or mixture using spent nuclear fuel or any isotopic source of high energy gamma radiation. For example, the level of applied dose required to decompose 400 ppm of polychlorinated biphenyl in transformer oil to less than 50 ppm is 500 kilograms. Destruction of polychlorinated biphenyls to levels of less than 50 ppm renders the transformer oil or transformer non-PCB contaminated under current regulations. Therefore, this process can be used to treat PCB contaminated oil and equipment to minimize or eliminate the generation of PCB hazardous waste. 5 figs.

Hospital management of mass radiological casualties: reassessing exposures from contaminated victims of an exploded radiological dispersal device.

PubMed

Smith, James M; Ansari, Armin; Harper, Frederick T

2005-11-01

One of the key issues in the aftermath of an exploded radiological dispersal device from a terrorist event is that of the contaminated victim and the concern among healthcare providers for the harmful exposures they may receive in treating patients, especially if the patient has not been thoroughly decontaminated. This is critically important in the event of mass casualties from a nuclear or radiological incident because of the essential rapidity of acute medical decisions and that those who have life- or limb-threatening injuries may have treatment unduly delayed by a decontamination process that may be unnecessary for protecting the health and safety of the patient or the healthcare provider. To estimate potential contamination of those exposed in a radiological dispersal device event, results were used from explosive aerosolization tests of surrogate radionuclides detonated with high explosives at the Sandia National Laboratories. Computer modeling was also used to assess radiation dose rates to surgical personnel treating patients with blast injuries who are contaminated with any of a variety of common radionuclides. It is demonstrated that exceptional but plausible cases may require special precautions by the healthcare provider, even while managing life-threatening injuries of a contaminated victim from a radiological dispersal device event.

TNT and RDX degradation and extraction from contaminated soil using subcritical water.

PubMed

Islam, Mohammad Nazrul; Shin, Moon-Su; Jo, Young-Tae; Park, Jeong-Hun

2015-01-01

The use of explosives either for industrial or military operations have resulted in the environmental pollution, poses ecological and health hazard. In this work, a subcritical water extraction (SCWE) process at laboratory scale was used at varying water temperature (100-175 °C) and flow rate (0.5-1.5 mL min(-1)), to treat 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) contaminated soil, to reveal information with respect to the explosives removal (based on the analyses of soil residue after extraction), and degradation performance (based on the analyses of water extracts) of this process. Continuous flow subcritical water has been considered on removal of explosives to avoid the repartitioning of non-degraded compounds to the soil upon cooling which usually occurs in the batch system. In the SCWE experiments, near complete degradation of both TNT and RDX was observed at 175 °C based on analysis of water extracts and soil. Test results also indicated that TNT removal of >99% and a complete RDX removal were achieved by this process, when the operating conditions were 1 mL min(-1), and treatment time of 20 min, after the temperature reached 175 °C. HPLC-UV and ion chromatography analysis confirmed that the explosives underwent for degradation. The low concentration of explosives found in the process wastewater indicates that water recycling may be viable, to treat additional soil. Our results have shown in the remediation of explosives contaminated soil, the effectiveness of the continuous flow SCWE process. Copyright © 2014 Elsevier Ltd. All rights reserved.

The ecological and physiological responses of the microbial community from a semiarid soil to hydrocarbon contamination and its bioremediation using compost amendment.

PubMed

Bastida, F; Jehmlich, N; Lima, K; Morris, B E L; Richnow, H H; Hernández, T; von Bergen, M; García, C

2016-03-01

The linkage between phylogenetic and functional processes may provide profound insights into the effects of hydrocarbon contamination and biodegradation processes in high-diversity environments. Here, the impacts of petroleum contamination and the bioremediation potential of compost amendment, as enhancer of the microbial activity in semiarid soils, were evaluated in a model experiment. The analysis of phospholipid fatty-acids (PLFAs) and metaproteomics allowed the study of biomass, phylogenetic and physiological responses of the microbial community in polluted semiarid soils. Petroleum pollution induced an increase of proteobacterial proteins during the contamination, while the relative abundance of Rhizobiales lowered in comparison to the non-contaminated soil. Despite only 0.55% of the metaproteome of the compost-treated soil was involved in biodegradation processes, the addition of compost promoted the removal of polycyclic aromatic hydrocarbons (PAHs) and alkanes up to 88% after 50 days. However, natural biodegradation of hydrocarbons was not significant in soils without compost. Compost-assisted bioremediation was mainly driven by Sphingomonadales and uncultured bacteria that showed an increased abundance of catabolic enzymes such as catechol 2,3-dioxygenases, cis-dihydrodiol dehydrogenase and 2-hydroxymuconic semialdehyde. For the first time, metaproteomics revealed the functional and phylogenetic relationships of petroleum contamination in soil and the microbial key players involved in the compost-assisted bioremediation. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluating the efficacy of bioremediating a diesel-contaminated soil using ecotoxicological and bacterial community indices.

PubMed

Khudur, Leadin Salah; Shahsavari, Esmaeil; Miranda, Ana F; Morrison, Paul D; Nugegoda, Dayanthi; Ball, Andrew S

2015-10-01

Diesel represents a common environmental contaminant as a result of operation, storage, and transportation accidents. The bioremediation of diesel in a contaminated soil is seen as an environmentally safe approach to treat contaminated land. The effectiveness of the remediation process is usually assessed by the degradation of the total petroleum hydrocarbon (TPH) concentration, without considering ecotoxicological effects. The aim of this study was to assess the efficacy of two bioremediation strategies in terms of reduction in TPH concentration together with ecotoxicity indices and changes in the bacterial diversity assessed using PCR-denaturing gradient gel electrophoresis (DGGE). The biostimulation strategy resulted in a 90 % reduction in the TPH concentration versus 78 % reduction from the natural attenuation strategy over 12 weeks incubation in a laboratory mesocosm-containing diesel-contaminated soil. In contrast, the reduction in the ecotoxicity resulting from the natural attenuation treatment using the Microtox and earthworm toxicity assays was more than double the reduction resulting from the biostimulation treatment (45 and 20 % reduction, respectively). The biostimulated treatment involved the addition of nitrogen and phosphorus in order to stimulate the microorganisms by creating an optimal C:N:P molar ratio. An increased concentration of ammonium and phosphate was detected in the biostimulated soil compared with the naturally attenuated samples before and after the remediation process. Furthermore, through PCR-DGGE, significant changes in the bacterial community were observed as a consequence of adding the nutrients together with the diesel (biostimulation), resulting in the formation of distinctly different bacterial communities in the soil subjected to the two strategies used in this study. These findings indicate the suitability of both bioremediation approaches in treating hydrocarbon-contaminated soil, particularly biostimulation. Although biostimulation represents a commercially viable bioremediation technology for use in diesel-contaminated soils, further research is required to determine the ecotoxicological impacts of the intervention.

Cost studies of thermally enhanced in situ soil remediation technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bremser, J.; Booth, S.R.

1996-05-01

This report describes five thermally enhanced technologies that may be used to remediate contaminated soil and water resources. The standard methods of treating these contaminated areas are Soil Vapor Extraction (SVE), Excavate & Treat (E&T), and Pump & Treat (P&T). Depending on the conditions at a given site, one or more of these conventional alternatives may be employed; however, several new thermally enhanced technologies for soil decontamination are emerging. These technologies are still in demonstration programs which generally are showing great success at achieving the expected remediation results. The cost savings reported in this work assume that the technologies willmore » ultimately perform as anticipated by their developers in a normal environmental restoration work environment. The five technologies analyzed in this report are Low Frequency Heating (LF or Ohmic, both 3 and 6 phase AC), Dynamic Underground Stripping (DUS), Radio Frequency Heating (RF), Radio Frequency Heating using Dipole Antennae (RFD), and Thermally Enhanced Vapor Extraction System (TEVES). In all of these technologies the introduction of heat to the formation raises vapor pressures accelerating contaminant evaporation rates and increases soil permeability raising diffusion rates of contaminants. The physical process enhancements resulting from temperature elevations permit a greater percentage of volatile organic compound (VOC) or semi- volatile organic compound (SVOC) contaminants to be driven out of the soils for treatment or capture in a much shorter time period. This report presents the results of cost-comparative studies between these new thermally enhanced technologies and the conventional technologies, as applied to five specific scenarios.« less

In situ bioventing at a natural gas dehydrator site: Field demonstration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawrence, A.W.; Miller, D.L.; Miller, J.A.

1995-12-31

This paper describes a bioventing/biosparging field demonstration that was conducted over a 10-month period at a former glycol dehydrator site located near Traverse City, Michigan. The goal of the project was to determine the feasibility of this technology for dehydrator site remediation and to develop engineering design concepts for applying bioventing/biosparging at similar sites. The chemicals of interest are benzene, toluene, ethylbenzene, and xylenes (BTEX) and alkanes. Soil sampling indicated that the capillary fringe and saturated zones were heavily contaminated, but that the unsaturated zone was relatively free of the contaminants. A pump-and-treat system has operated since 1991 to treatmore » the groundwater BTEX plume. Bioventing/biosparging was installed in September 1993 to treat the contaminant source area. Three different air sparging operating modes were tested to determine an optimal process configuration for site remediation. These operational modes were compared through in situ respirometry studies. Respirometry measurements were used to estimate biodegradation rates. Dissolved oxygen and carbon dioxide were monitored in the groundwater.« less

Development of a biotechnological process for the production of high quality linen fibers.

PubMed

Valladares Juárez, Ana Gabriela; Rost, Gernot; Heitmann, Uwe; Heger, Egon; Müller, Rudolf

2011-10-01

A novel biotechnological process for the production of high-quality flax fibers was developed. In this process, decorticated fibers from green flax were washed with 0.5% soda solution and treated with the pectinolytic strain Geobacillus thermoglucosidasius PB94A. Before drying the fibers, they were treated with the textile softener Adulcinol BUN. If the fibers contained contaminant shives, a bleaching step with hydrogen peroxide was performed before the softener treatment. In experiments where fibers were treated by the new process, and in which the bacterial solutions were reused seven times, the fiber quality was similar in all batches. The resolution of the treated fibers was 2.7 ± 0.4 and the fineness was 11.1 ± 1.1 dtex, while the starting material had a resolution of 7.3 and a fineness of 37 dtex. The new biotechnological treatment eliminates the weather-associated risks of the traditional fiber retting completely and produces consistently high-quality fibers that can be used to produce fine linen yarns.

Influence de l'alteration physique sur les caracteristiques physico-chimiques de monolithes de sols contamines traites par stabilisation/solidification au ciment

NASA Astrophysics Data System (ADS)

Remillard, Jonathan

The concern of contaminated sites is affecting millions of property owner worldwide. As they pose a risk to the environment, human health or impair the value of buildings, remediation of contaminated sites has become an everyday issue. Stabilization/solidification (S/S) of contaminated soils with cement is a remediation technology that was developed to confine contaminants that cannot be degraded biologically, chemically or thermally by other technologies. Soils treated with S/S form a monolith that can be valorized on site. However, this practice is fairly uncommon in Quebec and this reluctance is partly due to the risks of degradation of the monoliths and the lack of knowledge relative to the long-term behavior of altered monoliths. The objective of this project was to simulate these degradations on cement-based monoliths of contaminated soils treated with S/S technology by causing physical alterations using different cycles of freeze/thawing and drying/wetting, and then to study the impact of these alterations on the mass losses, compressive strength, hydraulic conductivity, pH and leachability of five trace metals (Cd, Cr, Cu, Pb and Zn) used as contaminants. Various processes of S/S have been studied, either cement contents of 15 and 20%, then the presence of 5% by weight of calcium carbonate. For each S/S process formulated, the freeze/thaw cycles were much more effective in physically altering the monoliths. These alterations were mainly reflected by lower compressive strength, even more with lower cement contents. For their part, the drying/wetting cycles rather created a chemical change that lowered the pH of the monoliths. These chemical changes also affected the interpretation of leaching test results, especially for copper and zinc, since it was difficult to attribute effects to either physical or chemical alterations. The results showed that only chromium leached more clearly in response to physical alterations. All other elements studied were little affected, even though some samples were highly altered. This demonstrates that in some cases, damages may have little impact on long-term performance of the monoliths in terms of contaminant immobilization. However, integrating the study of long-term behaviors of monoliths in a process of formulation for contaminated soil treatment with S/S can become paramount, as seen for chromium in this present study. Keywords: stabilization / solidification, deterioration, alteration, leachability, contaminants.

Characterizing Effects of Nitric Oxide Sterilization on tert-Butyl Acrylate Shape Memory Polymers

NASA Astrophysics Data System (ADS)

Phillippi, Ben

As research into the potential uses of shape memory polymers (SMPs) as implantable medical devices continues to grow and expand, so does the need for an accurate and reliable sterilization mechanism. The ability of an SMP to precisely undergo a programmed shape change will define its ability to accomplish a therapeutic task. To ensure proper execution of the in vivo shape change, the sterilization process must not negatively affect the shape memory behavior of the material. To address this need, this thesis investigates the effectiveness of a benchtop nitric oxide (NOx) sterilization process and the extent to which the process affects the shape memory behavior of a well-studied tert-Butyl Acrylate (tBA) SMP. Quantifying the effects on shape memory behavior was performed using a two-tiered analysis. A two-tiered study design was used to determine if the sterilization process induced any premature shape recovery and to identify any effects that NOx has on the overall shape memory behavior of the foams. Determining the effectiveness of the NOx system--specially, whether the treated samples are more sterile/less contaminated than untreated--was also performed with a two-tiered analysis. In this case, the two-tiered analysis was employed to have a secondary check for contamination. To elaborate, all of the samples that were deemed not contaminated from the initial test were put through a second sterility test to check for contamination a second time. The results of these tests indicated the NOx system is an effective sterilization mechanism and the current protocol does not negatively impact the shape memory behavior of the tBA SMP. The samples held their compressed shape throughout the entirety of the sterilization process. Additionally, there were no observable impacts on the shape memory behavior induced by NOx. Lastly, the treated samples demonstrated lower contamination than the untreated. This thesis demonstrates the effectiveness of NOx as a laboratory scale sterilization mechanism for heat triggered shape memory polymers. The shape memory analysis indicated that the magnitude of the length changes induced by NOx is small enough that it does not make a statistically significant impact on the shape memory behavior of the foams. Additionally, there were no observable effects on the shape memory behavior induced by NOx. The results further indicated the NOx system is effective at sterilizing porous scaffolds, as none of the sterilized samples showed contamination. Testing methods proved to be effective because the initial sterility test was able to identify all of the contaminated samples and preliminary results indicated that NOx sterilization improves the sterility of the foams.

Apparatus for treatment of soils contaminated with organic pollutants

DOEpatents

Wickramanayake, Godage B.

1993-01-01

An apparatus for treating soil contaminated by organic compounds wherein an ozone containing gas is treated with acid to increase the stability of the ozone in the soil environment and the treated ozone applied to the contaminated soil in a manner adapted to decompose the organic compounds; one embodiment of the apparatus comprises a means to supply ozone as a gas-ozone mixture, a stability means to treat ozone obtained from the supply and distribution means to apply the stabilized gas-ozone to soil. The soil may be treated in situ or may be removed for treatment and refilled.

Efficacy of forming biofilms by Pseudomonas migulae AN-1 toward in situ bioremediation of aniline-contaminated aquifer by groundwater circulation wells.

PubMed

Zhao, Yongsheng; Qu, Dan; Zhou, Rui; Yang, Shuai; Ren, Hejun

2016-06-01

The formation and activity of aniline-degrading biofilms developed by the psychrotrophic Pseudomonas migulae AN-1 were studied for the in situ remediation of contaminated aquifer using in-well bioreactor of groundwater circulating wells (GCWs). Biofilms grown in mineral salt medium with aniline exhibited tolerance to high concentrations of aniline. In aniline degradation rate, AN-1 biofilms exhibited slight differences compared with planktonic cells. The effectiveness and bio-implication of AN-1 biofilms in GCWs were investigated to treat aniline-contaminated aquifer. The results demonstrate that AN-1 biofilms survived the GCWs treatment process with high aniline-degrading efficiency. This system provides a novel environmentally friendly technology for the in situ bioremediation of low-volatile contaminants.

Treatment to Destroy Chlorohydrocarbon Liquids in the Ground

NASA Technical Reports Server (NTRS)

Quinn, Jacqueline; Clausen, Christian A., III; Geiger, Cherie L.; Reinhart, Debra; Brooks, Kathleen

2003-01-01

A relatively simple chemical treatment that involves the use of emulsified iron has been found to be effective in remediating groundwater contaminated with trichloroethylene and other dense chlorohydrocarbon liquids. These liquids are members of the class of dense, nonaqueous phase liquids (DNAPLs), which are commonly recognized to be particularly troublesome as environmental contaminants. The treatment converts these liquids into less-harmful products. As a means of remediation of contaminated groundwater, this treatment takes less time and costs less than do traditional pump-and-treat processes. At some sites, long-term leakage and/or dissolution of chlorohydrocarbon liquids from pools and/or sorbed concentrations in rock and soil gives rise to a need to continue pumpand- treat processes for times as long as decades in order to maintain protection of human health and the environment. In contrast, the effects of the emulsified-iron treatment are more lasting, decreasing the need for long-term treatment and monitoring of contaminated areas. The material used in this treatment consists of iron particles with sizes of the order of nanometers to micrometers contained within the micelles of a surfactant-stabilized, biodegradable, oil-in-water emulsion. The emulsion is simple to prepare and consists of relatively inexpensive and environmentally acceptable ingredients: One typical formulation consists of 1.3 weight percent of a food-grade surfactant, 17.5 weight percent of iron particles, 23.2 weight percent of vegetable oil, and 58.0 weight percent of water.

Thermal Destruction of TETS: Experiments and Modeling ...

EPA Pesticide Factsheets

Symposium Paper In the event of a contamination event involving chemical warfare agents (CWAs) or toxic industrial chemicals (TICs), large quantities of potentially contaminated materials, both indoor and outdoor, may be treated with thermal incineration during the site remediation process. Even if the CWAs or TICs of interest are not particularly thermally stable and might be expected to decompose readily in a high temperature combustion environment, the refractory nature of many materials found inside and outside buildings may present heat transfer challenges in an incineration system depending on how the materials are packaged and fed into the incinerator. This paper reports on a study to examine the thermal decomposition of a banned rodenticide, tetramethylene disulfotetramine (TETS) in a laboratory reactor, analysis of the results using classical reactor design theory, and subsequent scale-up of the results to a computer-simulation of a full-scale commercial hazardous waste incinerator processing ceiling tile contaminated with residual TETS.

In situ remediation process using divalent metal cations

DOEpatents

Brady, Patrick V.; Khandaker, Nadim R.; Krumhansl, James L.; Teter, David M.

2004-12-14

An in situ process for treating ambient solid materials (e.g., soils, aquifer solids, sludges) by adding one or more divalent metal cations to the ambient solid material. The added divalent metal cations, such as Cu.sup.2+ or Zn.sup.2+, combine with metal oxide/hydroxides (e.g., ferric oxide/hydroxide or aluminum oxide/hydroxide) already present in the ambient solid material to form an effective sorbent material having a large number of positively-charged surface complexes that binds and immobilizes anionic contaminant species (e.g., arsenic or chromate). Divalent metal cations can be added, for example, by injecting an aqueous solution of CuSO.sub.4 into an aquifer contaminated with arsenic or chromate. Also, sludges can be stabilized against leaching of anionic contaminants through the addition of divalent metal cations. Also, an inexpensive sorbent material can be easily formed by mixing divalent metal cations with soil that has been removed from the ground.

ENVIROMETAL TECHNOLOGIES, INC., METAL-ENHANCED DECHLORINATION OF VOLATILE ORGANIC COMPOUNDS USING AN IN-SITU REACTIVE IRON WALL

EPA Science Inventory

This report summarizes the results of a field demonstration conducted under the SITE program. The technology that was demonstrated was a metal-enhanced dechlorination process developed by EnviroMetal Technologies, Inc. to treat groundwater contaminated with chlorinated volatile ...

SITE TECHNOLOGY CAPSULE: IN SITU STEAM ENHANCED RECOVERY PROCESS

EPA Science Inventory

The SERP technology is designed to treat soils contaminated with VOCs and SVOCs in situ. Steam injection and vacuum extraction are used to remove the organic compounds from the soil and concentrate them for disposal or recycling. A full-scale demonstration of SERP was conducted a...

EMERGING TECHNOLOGY BULLETIN: RECLAMATION OF LEAD FROM SUPERFUND WASTE MATERIAL USING SECONDARY LEAD SMELTERS

EPA Science Inventory

This process involves incorporating lead-contaminated Superfund waste with the regular feed to a secondary lead smelter. Since secondary lead smelters already recover lead from recycled automobile batteries, it seems likely that this technology could be used to treat waste from ...

DEMONSTRATION BULLETIN: MOLECULAR BONDING SYSTEM FOR HEAVY METALS STABILIZATION - SOLUCORP INDUSTRIES LTD.

EPA Science Inventory

This document presents an evaluation of the Molecular Bonding System (MBS) and its ability to chemically stabilize three metals-contaminated wstes/soils during a SITe demo. The MBS process treated approximately 500 tons each of soil/Fill, Slag, and Miscellaneous Smelter Waste wit...

Electromagnetic mixed waste processing system for asbestos decontamination

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasevich, R.S.; Vaux, W.; Ulerich, N.

The overall objective of this three-phase program is to develop an integrated process for treating asbestos-containing material that is contaminated with radioactive and hazardous constituents. The integrated process will attempt to minimize processing and disposal costs. The objectives of Phase 1 were to establish the technical feasibility of asbestos decomposition, inorganic radionuclide nd heavy metal removal, and organic volatilization. Phase 1 resulted in the successful bench-scale demonstration of the elements required to develop a mixed waste treatment process for asbestos-containing material (ACM) contaminated with radioactive metals, heavy metals, and organics. Using the Phase 1 data, a conceptual process was developed.more » The Phase 2 program, currently in progress, is developing an integrated system design for ACM waste processing. The Phase 3 program will target demonstration of the mixed waste processing system at a DOE facility. The electromagnetic mixed waste processing system employs patented technologies to convert DOE asbestos to a non-hazardous, radionuclide-free, stable waste. The dry, contaminated asbestos is initially heated with radiofrequency energy to remove organic volatiles. Second,the radionuclides are removed by solvent extraction coupled with ion exchange solution treatment. Third, the ABCOV method converts the asbestos to an amorphous silica suspension at low temperature (100{degrees}C). Finally the amorphous silica is solidified for disposal.« less

Processes affecting the remediation of chromium-contaminated sites.

PubMed

Palmer, C D; Wittbrodt, P R

1991-05-01

The remediation of chromium-contaminated sites requires knowledge of the processes that control the migration and transformation of chromium. Advection, dispersion, and diffusion are physical processes affecting the rate at which contaminants can migrate in the subsurface. Heterogeneity is an important factor that affects the contribution of each of these mechanisms to the migration of chromium-laden waters. Redox reactions, chemical speciation, adsorption/desorption phenomena, and precipitation/dissolution reactions control the transformation and mobility of chromium. The reduction of CrVI to CrIII can occur in the presence of ferrous iron in solution or in mineral phases, reduced sulfur compounds, or soil organic matter. At neutral to alkaline pH, the CrIII precipitates as amorphous hydroxides or forms complexes with organic matter. CrIII is oxidized by manganese dioxide, a common mineral found in many soils. Solid-phase precipitates of hexavalent chromium such as barium chromate can serve either as sources or sinks for CrVI. Adsorption of CrVI in soils increases with decreasing chromium concentration, making it more difficult to remove the chromium as the concentration decreases during pump-and-treat remediation. Knowledge of these chemical and physical processes is important in developing and selecting effective, cost-efficient remediation designs for chromium-contaminated sites.

Simulating Mass Removal of Groundwater Contaminant Plumes with Complex and Simple Models

NASA Astrophysics Data System (ADS)

Lopez, J.; Guo, Z.; Fogg, G. E.

2016-12-01

Chlorinated solvents used in industrial, commercial, and other applications continue to pose significant threats to human health through contamination of groundwater resources. A recent National Research Council report concludes that it is unlikely that remediation of these complex sites will be achieved in a time frame of 50-100 years under current methods and standards (NRC, 2013). Pump and treat has been a common strategy at many sites to contain and treat groundwater contamination. In these sites, extensive retention of contaminant mass in low-permeability materials (tailing) has been observed after years or decades of pumping. Although transport models can be built that contain enough of the complex, 3D heterogeneity to simulate the tailing and long cleanup times, this is seldom done because of the large data and computational burdens. Hence, useful, reliable models to simulate various cleanup strategies are rare. The purpose of this study is to explore other potential ways to simulate the mass-removal processes with shorter time and less cost but still produce robust results by capturing effects of the heterogeneity and long-term retention of mass. A site containing a trichloroethylene groundwater plume was selected as the study area. The plume is located within alluvial sediments in the Tucson Basin. A fully heterogeneous domain is generated first and MODFLOW is used to simulate the flow field. Contaminant transport is simulated using both MT3D and RWHet for the fully heterogeneous model. Other approaches, including dual-domain mass transfer and heterogeneous chemical reactions, are manipulated to simulate the mass removal in a less heterogeneous, or homogeneous, domain and results are compared to the results obtained from complex models. The capability of these simpler models to simulate remediation processes, especially capture the late-time tailing, are examined.

Nationwide reconnaissance of contaminants of emerging concern in source and treated drinking waters of the United States: Pharmaceuticals

EPA Science Inventory

Mobile and persistent chemicals that are present in urban wastewater, such as pharmaceuticals, may survive on-site or municipal wastewater treatment and post-discharge environmental processes. These pharmaceuticals have the potential to reach surface and groundwaters, essential d...

CHARACTERIZATION AND FATE OF PAH-CONTAMINATED SEDIMENTS AT THE WYCKOFF/EAGLE HARBOR SUPERFUND SITE

EPA Science Inventory

Eagle Harbor is a shallow marine embayment of Bainbridge Island, WA and formerly the site of the Wyckoff wood-treatment facility. The facility became operational in the early 1900s and used large quantities of creosote in its wood-treating processes. Creosote percolated through t...

Influences of thermal decontamination on mercury removal, soil properties, and repartitioning of coexisting heavy metals.

PubMed

Huang, Yu-Tuan; Hseu, Zeng-Yei; Hsi, Hsing-Cheng

2011-08-01

Thermal treatment is a useful tool to remove Hg from contaminated soils. However, thermal treatment may greatly alter the soil properties and cause the coexisting contaminants, especially trace metals, to transform and repartition. The metal repartitioning may increase the difficulty in the subsequent process of a treatment train approach. In this study, three Hg-contaminated soils were thermally treated to evaluate the effects of treating temperature and duration on Hg removal. Thermogravimetric analysis was performed to project the suitable heating parameters for subsequent bench-scale fixed-bed operation. Results showed that thermal decontamination at temperature>400°C successfully lowered the Hg content to<20 mg kg(-1). The organic carbon content decreased by 0.06-0.11% and the change in soil particle size was less significant, even when the soils were thermally treated to 550°C. Soil clay minerals such as kaolinite were shown to be decomposed. Aggregates were observed on the surface of soil particles after the treatment. The heavy metals tended to transform into acid-extractable, organic-matter bound, and residual forms from the Fe/Mn oxide bound form. These results suggest that thermal treatment may markedly influence the effectiveness of subsequent decontamination methods, such as acid washing or solvent extraction. Copyright © 2011 Elsevier Ltd. All rights reserved.

Treatment wetlands in decentralised approaches for linking sanitation to energy and food security.

PubMed

Langergraber, Guenter; Masi, Fabio

2018-02-01

Treatment wetlands (TWs) are engineered systems that mimic the processes in natural wetlands with the purpose of treating contaminated water. Being a simple and robust technology, TWs are applied worldwide to treat various types of water. Besides treated water for reuse, TWs can be used in resources-oriented sanitation systems for recovering nutrients and carbon, as well as for growing biomass for energy production. Additionally, TWs provide a large number of ecosystem services. Integrating green infrastructure into urban developments can thus facilitate circular economy approaches and has positive impacts on environment, economy and health.

Development of a Screening Tool to Facilitate Technology Transfer of an Innovative Technology to Treat Perchlorate-Contaminated Water

DTIC Science & Technology

2008-03-01

foods such as fruits, vegetables, and beverages (U.S. FDA, 2004). If the U.S. EPA ultimately establishes a drinking water standard for perchlorate...TREAT PERCHLORATE-CONTAMINATED WATER THESIS Daniel A. Craig, Captain, USAF AFIT/GEM/ENV/08-M06 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY...OF AN INNOVATIVE TECHNOLOGY TO TREAT PERCHLORATE- CONTAMINATED WATER THESIS Presented to the Faculty Department of Systems and Engineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Becker, C.D.; Woodfield, W.G.; Strand, J.A.

The Freshwater Sciences Section of PNL has initiated biologically oriented studies at the P and M solvent refined coal (SRC) pilot plant on the Fort Lewis Reservation in western Washington. Essentially, the study objectives are to identify residual components in the treated SRC process and assess potential for adverse impact on water quality and aquatic biota. Since inception of research in mid-1976, six static toxicity tests with treated SRC process effluent have been conducted. Toxic components, not yet specifically identified, sometimes occur in the effluent. It is believed these components involve organic hydrocarbons of the phenol and cresol groups. Analysesmore » have been obtained on inorganic and organic constituents in partially-treated and treated process effluent. Concentrations of inorganics identified in the effluent did not differ greatly from their concentrations in Lake Sequalitchew or SRC plant tap water, but the low concentrations may be due primarily to dilution with freshwater before discharge. Organics identified in the effluent are similar to those found in samples contaminated with petroleum, and involve many complex hydrocarbons.« less

Assessing the Impact of Chlorinated-Solvent Sites on Metropolitan Groundwater Resources

PubMed Central

Brusseau, Mark L.; Narter, Matthew

2014-01-01

Chlorinated-solvent compounds are among the most common groundwater contaminants in the U.S.A. The majority of the many sites contaminated by chlorinated-solvent compounds are located in metropolitan areas, and most such areas have one or more chlorinated-solvent contaminated sites. Thus, contamination of groundwater by chlorinated-solvent compounds may pose a potential risk to the sustainability of potable water supplies for many metropolitan areas. The impact of chlorinated-solvent sites on metropolitan water resources was assessed for Tucson, AZ, by comparing the aggregate volume of extracted groundwater for all pump-and-treat systems associated with contaminated sites in the region to the total regional groundwater withdrawal. The analysis revealed that the aggregate volume of groundwater withdrawn for the pump-and-treat systems operating in Tucson, all of which are located at chlorinated-solvent contaminated sites, was 20% of the total groundwater withdrawal in the city for the study period. The treated groundwater was used primarily for direct delivery to local water supply systems or for reinjection as part of the pump-and-treat system. The volume of the treated groundwater used for potable water represented approximately 13% of the total potable water supply sourced from groundwater, and approximately 6% of the total potable water supply. This case study illustrates the significant impact chlorinated-solvent contaminated sites can have on groundwater resources and regional potable-water supplies. PMID:24116872

Aerobic Toluene Degraders in the Rhizosphere of a Constructed Wetland Model Show Diurnal Polyhydroxyalkanoate Metabolism.

PubMed

Lünsmann, Vanessa; Kappelmeyer, Uwe; Taubert, Anja; Nijenhuis, Ivonne; von Bergen, Martin; Heipieper, Hermann J; Müller, Jochen A; Jehmlich, Nico

2016-07-15

Constructed wetlands (CWs) are successfully applied for the treatment of waters contaminated with aromatic compounds. In these systems, plants provide oxygen and root exudates to the rhizosphere and thereby stimulate microbial degradation processes. Root exudation of oxygen and organic compounds depends on photosynthetic activity and thus may show day-night fluctuations. While diurnal changes in CW effluent composition have been observed, information on respective fluctuations of bacterial activity are scarce. We investigated microbial processes in a CW model system treating toluene-contaminated water which showed diurnal oscillations of oxygen concentrations using metaproteomics. Quantitative real-time PCR was applied to assess diurnal expression patterns of genes involved in aerobic and anaerobic toluene degradation. We observed stable aerobic toluene turnover by Burkholderiales during the day and night. Polyhydroxyalkanoate synthesis was upregulated in these bacteria during the day, suggesting that they additionally feed on organic root exudates while reutilizing the stored carbon compounds during the night via the glyoxylate cycle. Although mRNA copies encoding the anaerobic enzyme benzylsuccinate synthase (bssA) were relatively abundant and increased slightly at night, the corresponding protein could not be detected in the CW model system. Our study provides insights into diurnal patterns of microbial processes occurring in the rhizosphere of an aquatic ecosystem. Constructed wetlands are a well-established and cost-efficient option for the bioremediation of contaminated waters. While it is commonly accepted knowledge that the function of CWs is determined by the interplay of plants and microorganisms, the detailed molecular processes are considered a black box. Here, we used a well-characterized CW model system treating toluene-contaminated water to investigate the microbial processes influenced by diurnal plant root exudation. Our results indicated stable aerobic toluene degradation by members of the Burkholderiales during the day and night. Polyhydroxyalkanoate synthesis in these bacteria was higher during the day, suggesting that they additionally fed on organic root exudates and reutilized the stored carbon compounds during the night. Our study illuminates microbial processes occurring in the rhizosphere of an aquatic ecosystem. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Aerobic Toluene Degraders in the Rhizosphere of a Constructed Wetland Model Show Diurnal Polyhydroxyalkanoate Metabolism

PubMed Central

Lünsmann, Vanessa; Kappelmeyer, Uwe; Taubert, Anja; Nijenhuis, Ivonne; von Bergen, Martin; Müller, Jochen A.; Jehmlich, Nico

2016-01-01

ABSTRACT Constructed wetlands (CWs) are successfully applied for the treatment of waters contaminated with aromatic compounds. In these systems, plants provide oxygen and root exudates to the rhizosphere and thereby stimulate microbial degradation processes. Root exudation of oxygen and organic compounds depends on photosynthetic activity and thus may show day-night fluctuations. While diurnal changes in CW effluent composition have been observed, information on respective fluctuations of bacterial activity are scarce. We investigated microbial processes in a CW model system treating toluene-contaminated water which showed diurnal oscillations of oxygen concentrations using metaproteomics. Quantitative real-time PCR was applied to assess diurnal expression patterns of genes involved in aerobic and anaerobic toluene degradation. We observed stable aerobic toluene turnover by Burkholderiales during the day and night. Polyhydroxyalkanoate synthesis was upregulated in these bacteria during the day, suggesting that they additionally feed on organic root exudates while reutilizing the stored carbon compounds during the night via the glyoxylate cycle. Although mRNA copies encoding the anaerobic enzyme benzylsuccinate synthase (bssA) were relatively abundant and increased slightly at night, the corresponding protein could not be detected in the CW model system. Our study provides insights into diurnal patterns of microbial processes occurring in the rhizosphere of an aquatic ecosystem. IMPORTANCE Constructed wetlands are a well-established and cost-efficient option for the bioremediation of contaminated waters. While it is commonly accepted knowledge that the function of CWs is determined by the interplay of plants and microorganisms, the detailed molecular processes are considered a black box. Here, we used a well-characterized CW model system treating toluene-contaminated water to investigate the microbial processes influenced by diurnal plant root exudation. Our results indicated stable aerobic toluene degradation by members of the Burkholderiales during the day and night. Polyhydroxyalkanoate synthesis in these bacteria was higher during the day, suggesting that they additionally fed on organic root exudates and reutilized the stored carbon compounds during the night. Our study illuminates microbial processes occurring in the rhizosphere of an aquatic ecosystem. PMID:27129963

Interior microelectrolysis oxidation of polyester wastewater and its treatment technology.

PubMed

Yang, Xiaoyi

2009-09-30

This paper has investigated the effects of interior microelectrolysis pretreatment on polyester wastewater treatment and analyzed its mechanism on COD and surfactant removal. The efficiency of interior microelectrolysis is mainly influenced by solution pH, aeration and reaction time. Contaminants can be removed not only by redox reaction and flocculation in the result of ferrous and ferric hydroxides but also by electrophoresis under electric fields created by electron flow. pH confirms the chemical states of surfactants, Fe(II)/Fe(III) ratio and the redox potential, and thus influences the effects of electrophoresis, flocculation and redox action on contaminant removal. Anaerobic and aerobic batch tests were performed to study the degradation of polyester wastewater. The results imply that interior microelectrolysis and anaerobic pretreatment are lacking of effectiveness if applied individually in treating polyester wastewater in spite of their individual advantages. The interior microelectrolysis-anaerobic-aerobic process was investigated to treat polyester wastewater with comparison with interior microelectrolysis-aerobic process and anaerobic-aerobic process. High COD removal efficiencies have been gotten by the combination of interior microelectrolysis with anaerobic technology and aerobic technology. The results also imply that only biological treatment was less effective in polyester wastewater treatment.

The importance of quality control in validating concentrations of contaminants of emerging concern in source and treated drinking water samples.

EPA Science Inventory

A national-scale survey of 247 contaminants of emerging concern (CECs), including organic and inorganic chemical compounds, and microbial contaminants, was conducted in source and treated drinking water samples from 25 treatment plants across the United States. Multiple methods w...

Surface analysis of 316 stainless steel treated with cold atmospheric plasma

NASA Astrophysics Data System (ADS)

Williams, David F.; Kellar, Ewen J. C.; Jesson, David A.; Watts, John F.

2017-05-01

The surface of 316 stainless steel has been modified using cold atmospheric plasma (CAP) to increase the surface free energy (by cleaning the and chemically activating the surface)IN preparation for subsequent processes such as painting, coating or adhesive bonding. The analyses carried out, on CAP treated 316 stainless steel surfaces, includes X-ray photoelectron spectroscopy (XPS), imaging XPS (iXPS), and surface free energy (SFE) analysis using contact angle measurements. The CAP treatment is shown to increase the SFE of as-received 316 stainless steel from ∼39 mJ m-1 to >72 mJ m-1 after a short exposure to the plasma torch. This was found to correlate to a reduction in adventitious carbon, as determined by XPS analysis of the surface. The reduction from ∼90 at% to ∼30% and ∼39 at%, after being plasma treated for 5 min and 15 s respectively, shows that the process is relatively quick at changing the surface. It is suggested that the mechanism that causes the increase in surface free energy is chain scission of the hydrocarbon contamination triggered by free electrons in the plasma plume followed by chemical functionalisation of the metal oxide surface and some of the remaining carbon contamination layer.

ADSORPTION OF LEAD FROM A CONTAMINATED SOIL TREATED WITH PHOSPHORUS AND MANGANESE OXIDES BY APRAGUE-DAWLEY RATS

EPA Science Inventory

In addition to the formation of insoluble lead (Pb) compounds as a mean of reducing Pb bioavalability, adsorption is another potentially important process controlling the bioavailability of Pb in soils. Less attention has been given to manganese (Mn) oxides, even though they are ...

9 CFR 145.83 - Terminology and classification; flocks and products.

Code of Federal Regulations, 2010 CFR

2010-01-01

... manufacturing process; (B) Mash feed may contain animal protein if the finished feed is treated with a salmonella control product approved by the U.S. Food and Drug Administration. (C) All feed is stored and transported in such a manner as to prevent possible contamination. (iii) The flock is maintained in compliance...

The activation energy of stabilised/solidified contaminated soils.

PubMed

Chitambira, B; Al-Tabbaa, A; Perera, A S R; Yu, X D

2007-03-15

Developing an understanding of the time-related performance of cement-treated materials is essential in understanding their durability and long-term effectiveness. A number of models have been developed to predict this time-related performance. One such model is the maturity concept which involves use of the 'global' activation energy which derives from the Arrhenius equation. The accurate assessment of the activation energy is essential in the realistic modelling of the accelerated ageing of cement-treated soils. Experimentally, this model is applied to a series of tests performed at different elevated temperatures. Experimental work, related to the results of a time-related performance on a contaminated site in the UK treated with in situ stabilisation/solidification was carried out. Three different cement-based grouts were used on two model site soils which were both contaminated with a number of heavy metals and a hydrocarbon. Uncontaminated soils were also tested. Elevated temperatures up to 60 degrees C and curing periods up to 90 days were used. The resulting global activation energies for the uncontaminated and contaminated soils were compared. Lower values were obtained for the contaminated soils reflecting the effect of the contaminants. The resulting equivalent ages for the uncontaminated and contaminated mixes tested were 5.1-7.4 and 0.8-4.1 years, respectively. This work shows how a specific set of contaminants affect the E(a) values for particular cementitious systems and how the maturity concept can be applied to cement-treated contaminated soils.

"Green technology": Bio-stimulation by an electric field for textile reactive dye contaminated agricultural soil.

PubMed

Annamalai, Sivasankar; Santhanam, Manikandan; Selvaraj, Subbulakshmi; Sundaram, Maruthamuthu; Pandian, Kannan; Pazos, Marta

2018-05-15

The aim of the study is to degrade pollutants as well as to increase the fertility of agricultural soil by starch enhancing electrokinetic (EKA) and electro-bio-stimulation (EBS) processes. Starch solution was used as an anolyte and voltage gradient was about 0.5V/cm. The influence of bacterial mediated process was evaluated in real contaminated farming soil followed by pilot scale experiment. The in-situ formation of β-cyclodextrin from starch in the treatments had also influence on the significant removal of the pollutants from the farming soil. The conductivity of the soil was effectively reduced from 15.5dS/m to 1.5dS/m which corroborates well with the agricultural norms. The bio-stimulation was confirmed by the increase of the phosphorus content in the treated soil. Finally, phytotoxicity assays demonstrated the viability of the developed technique for soil remediation because plant germination percentage was higher in the treated soil in comparison to untreated soil. Copyright © 2017 Elsevier B.V. All rights reserved.

Fractionation study in bioleached metallurgy wastes using six-step sequential extraction.

PubMed

Krasnodebska-Ostrega, Beata; Pałdyna, Joanna; Kowalska, Joanna; Jedynak, Łukasz; Golimowski, Jerzy

2009-08-15

The stored metallurgy wastes contain residues from ore processing operations that are characterized by relatively high concentrations of heavy metals. The bioleaching process makes use of bacteria to recover elements from industrial wastes and to decrease potential risk of environmental contamination. Wastes were treated by solutions containing bacteria. In this work, the optimized six-stage sequential extraction procedure was applied for the fractionation of Ni, Cr, Fe, Mn, Cu and Zn in iron-nickel metallurgy wastes deposited in Southern Poland (Szklary). Fractionation and total concentrations of elements in wastes before and after various bioleaching treatments were studied. Analyses of the extracts were performed by ICP-MS and FAAS. To achieve the most effective bioleaching of Zn, Cr, Ni, Cu, Mn, Fe the usage of both autotrophic and heterotrophic bacteria in sequence, combined with flushing of the residue after bioleaching is required. 80-100% of total metal concentrations were mobilized after the proposed treatment. Wastes treated according to this procedure could be deposited without any risk of environmental contamination and additionally the metals could be recovered for industrial purposes.

Contribution of treated wastewater to the microbiological quality of Seine River in Paris.

PubMed

Moulin, Laurent; Richard, Fanny; Stefania, Sabrina; Goulet, Marion; Gosselin, Sylvie; Gonçalves, Alexandre; Rocher, Vincent; Paffoni, Catherine; Dumètre, Aurélien

2010-10-01

Urban part of Seine River serving as drinking water supply in Paris can be heavily contaminated by Cryptosporidium spp. and Giardia duodenalis. In the absence of agricultural practice in this highly urbanized area, we investigated herein the contribution of treated wastewater to the microbiological quality of this river focusing on these two parasites. Other microorganisms such as faecal bacterial indicators, enteroviruses and oocysts of Toxoplasma gondii were assessed concurrently. Raw wastewaters were heavily contaminated by Cryptosporidium and Giardia (oo)cysts, whereas concentrations of both protozoa in treated wastewater were lower. Treated wastewater, flowed into Seine River, had a parasite concentration closed to the one found along the river, in particular at the entry of a drinking water plant (DWP). Even if faecal bacteria were reliable indicators of a reduction in parasite concentrations during the wastewater treatment, they were not correlated to protozoal contamination of wastewater and river water. Oocysts of T. gondii were not found in both raw and treated wastewater, or in Seine River. Parasitic contamination was shown to be constant in the Seine River up to 40 km upstream Paris. Altogether, these results strongly suggest that treated wastewater does not contribute to the main parasitic contamination of the Seine River usually observed in this urbanized area. Copyright © 2010 Elsevier Ltd. All rights reserved.

Thermal-treated soil for mercury removal: Soil and phytotoxicity tests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roh, Y.; Edwards, N.T.; Lee, S.Y.

Mercury (Hg) contamination of soils and sediments is one of many environmental problems at the Oak Ridge Reservation, Oak Ridge, TN. Mercury-contaminated soil from the Lower East Fork Poplar Creek (LEFPC) at the Oak Ridge Reservation was treated thermally to reduce Hg concentration to a below target level (20 mg kg{sup {minus}1}) as a pilot scale thermal treatment demonstration. As a part of performance evaluation, the soil characteristics and plant growth response of the untreated and treated soil were examined. The soil treated at 350 C retained most of its original soil properties, but the soil treated at 600 Cmore » exhibited considerable changes in mineralogical composition and physicochemical characteristics. Growth and physiological response of the three plant species radish (Raphanus sativus L.), fescue (Festuca arundinacea Schreb.), and oat (Avena sativa L.) indicated adverse effects of the thermal treatment. The addition of N fertilizer had beneficial effects in the 350 C treated soil, but had little beneficial effect in the 600 C treated soil. Some changes of soil characteristics induced by thermal treatment cannot be avoided. Soil characteristics and phytotoxicity test results strongly suggest that changes occurring following the 350 C treatment do not limit the use of the treated soil to refill the excavated site for full-scale remediation. The only problem with the 350 C treatment is that small amounts of Hg compounds (<15 mg kg{sup {minus}1}) remain in the soil and a processing cost of $45/Mg.« less

Killing of Campylobacter on contaminated plastic and wooden cutting boards by glycerol monocaprate (monocaprin).

PubMed

Thormar, H; Hilmarsson, H

2010-09-01

Contamination in the kitchen with foodborne bacteria is a risk factor in human exposure to these pathogens, an important route being transfer of bacteria from contaminated cutting boards and other surfaces to humans. The aim of this study was to test microbicidal emulsions of glycerol monocaprate (monocaprin) against Campylobacter on contaminated cutting boards. Plastic and wooden cutting boards, soiled with meat juice heavily contaminated with Campylobacter, were treated for 2 min with emulsions of monocaprin (MC) made in water or in buffer at low pH. Viable Campylobacter counts were reduced below the detectable level on plastic board surfaces after treatment with MC emulsions with or without 1.25% washing-up liquids (WUL). The counts were also greatly reduced on wooden boards (P < 0.05). Monocaprin emulsions and mixtures of MC emulsions and WUL may be useful as sanitizers/disinfectants in kitchens and in other food preparing and processing facilities. Cleaning with MC emulsions with or without WUL may reduce the risk of human exposure to Campylobacter.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scrudato, R.J.; Chiarenzelli, J.R.

An electrochemical peroxidation (ECP) process has been developed and used to degrade polychlorinated biphenyls (PCB) and volatile organic compounds (VOC)-contaminated water, sludge, and sediments at a New York State Federal and State Superfund Site. The process involves passing an oscillating low-amperage (<10 amps) current through steel electrodes immersed in an acidified water or sediment slurry into which hydrogen peroxide (<1,000 ppm) is added. The generated free radicals attack organic compounds, including organo-metallic complexes and refractory compounds including PCBs. PCB degradation ranged from about 30% to 80% in experiments involving Federal Superfund Site sediments; total PCBs were reduced by {approximately}97% tomore » 68%, respectively, in water and slurry collected from a State Superfund subsurface storage tank. VOC bench-scale experiments involved chloroethane, 1,1-dichloroethane, dichloromethane, 1,1,1-trichloroethane, and acetone and after a 3-min ECP treatment, degradation ranged from >94% to about 99.9%. Results indicate the ECP is a viable process to degrade organic contaminants in water and sediment suspensions. Because the treated water suspensions are acidified, select trace metal sorbed to the particulates is solubilized and therefore can be segregated from the particulates, offering a process that simultaneously degrades organic contaminants and separates trace metals. 19 refs., 1 fig., 4 tabs.« less

Effective solidification/stabilisation of mercury-contaminated wastes using zeolites and chemically bonded phosphate ceramics.

PubMed

Zhang, Shaoqing; Zhang, Xinyan; Xiong, Ya; Wang, Guoping; Zheng, Na

2015-02-01

In this study, two kinds of zeolites materials (natural zeolite and thiol-functionalised zeolite) were added to the chemically bonded phosphate ceramic processes to treat mercury-contaminated wastes. Strong promotion effects of zeolites (natural zeolite and thiol-functionalised zeolite) on the stability of mercury in the wastes were obtained and these technologies showed promising advantages toward the traditional Portland cement process, i.e. using Portland cement as a solidification agent and natural or thiol-functionalised zeolite as a stabilisation agent. Not only is a high stabilisation efficiency (lowered the Toxicity Characteristic Leaching Procedure Hg by above 10%) obtained, but also a lower dosage of solidification (for thiol-functionalised zeolite as stabilisation agent, 0.5 g g(-1) and 0.7 g g(-1) for chemically bonded phosphate ceramic and Portland cement, respectively) and stabilisation agents (for natural zeolite as stabilisation agent, 0.35 g g(-1) and 0.4 g g(-1) for chemically bonded phosphate ceramic and Portland cement, respectively) were used compared with the Portland cement process. Treated by thiol-functionalised zeolite and chemically bonded phosphate ceramic under optimum parameters, the waste containing 1500 mg Hg kg(-1) passed the Toxicity Characteristic Leaching Procedure test. Moreover, stabilisation/solidification technology using natural zeolite and chemically bonded phosphate ceramic also passed the Toxicity Characteristic Leaching Procedure test (the mercury waste containing 625 mg Hg kg(-1)). Moreover, the presence of chloride and phosphate did not have a negative effect on the chemically bonded phosphate ceramic/thiol-functionalised zeolite treatment process; thus, showing potential for future application in treatment of 'difficult-to-manage' mercury-contaminated wastes or landfill disposal with high phosphate and chloride content. © The Author(s) 2015.

Binding mechanism of patulin to heat-treated yeast cell.

PubMed

Guo, C; Yuan, Y; Yue, T; Hatab, S; Wang, Z

2012-12-01

This study aims to assess the removal mechanism of patulin using heat-treated Saccharomyces cerevisiae cells and identify the role of different cell wall components in the binding process. In order to understand the binding mechanism, viable cells, heat-treated cells, cell wall and intracellular extract were performed to assess their ability to remove patulin. Additionally, the effects of chemical and enzymatic treatments of yeast on the binding ability were tested. The results showed that there was no significant difference between viable (53·28%) and heat-treated yeast cells (51·71%) in patulin binding. In addition, the cell wall fraction decreased patulin by 35·05%, and the cell extract nearly failed to bind patulin. Treatments with protease E, methanol, formaldehyde, periodate or urea significantly decreased (P < 0·05) the ability of heat-treated cells to remove patulin. Fourier transform infrared (FTIR) analysis indicated that more functional groups were involved in the binding process of heat-treated cells. Polysaccharides and protein are important components of yeast cell wall involved in patulin removal. In addition, hydrophobic interactions play a major role in binding processes. Heat-treated S. cerevisiae cells could be used to control patulin contamination in the apple juice industry. Also, our results proof that the patulin removal process is based mainly on the adsorption not degradation. © 2012 The Society for Applied Microbiology.

Investigations into the application of a combination of bioventing and biotrickling filter technologies for soil decontamination processes--a transition regime between bioventing and soil vapour extraction.

PubMed

Magalhães, S M C; Ferreira Jorge, R M; Castro, P M L

2009-10-30

Bioventing has emerged as one of the most cost-effective in situ technologies available to address petroleum light-hydrocarbon spills, one of the most common sources of soil pollution. However, the major drawback associated with this technology is the extended treatment time often required. The present study aimed to illustrate how an intended air-injection bioventing technology can be transformed into a soil vapour extraction effort when the air flow rates are pushed to a stripping mode, thus leading to the treatment of the off-gas resulting from volatilisation. As such, a combination of an air-injection bioventing system and a biotrickling filter was applied for the treatment of contaminated soil, the latter aiming at the treatment of the emissions resulting from the bioventing process. With a moisture content of 10%, soil contaminated with toluene at two different concentrations, namely 2 and 14 mg g soil(-1), were treated successfully using an air-injection bioventing system at a constant air flow rate of ca. 0.13 dm(3) min(-1), which led to the removal of ca. 99% toluene, after a period of ca. 5 days of treatment. A biotrickling filter was simultaneously used to treat the outlet gas emissions, which presented average removal efficiencies of ca. 86%. The proposed combination of biotechnologies proved to be an efficient solution for the decontamination process, when an excessive air flow rate was applied, reducing both the soil contamination and the outlet gas emissions, whilst being able to reduce the treatment time required by bioventing only.

Superfund record of decision (EPA Region 4): Milan Army Ammunition Plant, operable units 3 and 4, Milan, TN, October 2, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-03-01

This decision document presents the selected remedial action for the soil within the northern industrial area of Milan Army Ammunition Plant, Milan, Tennessee. The goal of the cleanup activities at the northern industrial areas of MAAP is to remove the soil contaminated with explosives compounds above risk-based levels. The excavated soil will be treated using a bioremediation process to reduce the concentrations of explosives compounds, the toxicity of the leachate, and the mobility of the remaining organic compounds. The treated soil will then be placed in an on-site solid waste landfill in compliance with State of Tennessee regulations. Additionally, inmore » areas where excavation of the explosives-contaminated soil is infeasible, the soil will be covered with an engineered cap to prevent worker exposure to the explosives compounds and prevent leaching of these compounds to groundwater.« less

POLYNUCLEAR AROMATIC HYDROCARBON (PAH) RELEASE FROM SOIL DURING TREATMENT WITH FENTON'S REAGENT

EPA Science Inventory

Fenton's Reagent was used to treat soil from a wood-treating site in southeastern Ohio which had been contaminated with creosote. Slurries, consisting of 10 µg of contaminated soil and 30 mL water were treated with 40 mL of Fenton's Reagent (1:1 of 30% H₂O₂ ...

Innovative Use of Cr(VI) Plume Depictions and Pump-and-Treat Capture Analysis to Estimate Risks of Contaminant Discharge to Surface Water at Hanford Reactor Areas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Chuck W.; Hanson, James P.; Ivarson, Kristine A.

2015-01-14

The Hanford Site nuclear reactor operations required large quantities of high-quality cooling water, which was treated with chemicals including sodium dichromate dihydrate for corrosion control. Cooling water leakage, as well as intentional discharge of cooling water to ground during upset conditions, produced extensive groundwater recharge mounds consisting largely of contaminated cooling water and resulted in wide distribution of hexavalent chromium (Cr[VI]) contamination in the unconfined aquifer. The 2013 Cr(VI) groundwater plumes in the 100 Areas cover approximately 6 km2 (1500 acres), primarily in the 100-HR-3 and 100-KR-4 groundwater operable units (OUs). The Columbia River is a groundwater discharge boundary; wheremore » the plumes are adjacent to the Columbia River there remains a potential to discharge Cr(VI) to the river at concentrations above water quality criteria. The pump-and-treat systems along the River Corridor are operating with two main goals: 1) protection of the Columbia River, and 2) recovery of contaminant mass. An evaluation of the effectiveness of the pump-and-treat systems was needed to determine if the Columbia River was protected from contamination, and also to determine where additional system modifications may be needed. In response to this need, a technique for assessing the river protection was developed which takes into consideration seasonal migration of the plume and hydraulic performance of the operating well fields. Groundwater contaminant plume maps are generated across the Hanford Site on an annual basis. The assessment technique overlays the annual plume and the capture efficiency maps for the various pump and treat systems. The river protection analysis technique was prepared for use at the Hanford site and is described in detail in M.J. Tonkin, 2013. Interpolated capture frequency maps, based on mapping dynamic water level observed in observation wells and derived water levels in the vicinity of extraction and injection wells, are developed initially. Second, simulated capture frequency maps are developed, based on transport modelling results. Both interpolated and simulated capture frequency maps are based on operation of the systems over a full year. These two capture maps are then overlaid on the plume distribution maps for inspection of the relative orientation of the contaminant plumes with the capture frequency. To quantify the relative degree of protection of the river from discharges of Cr(VI) (and conversely, the degree of threat) at any particular location, a systematic method of evaluating and mapping the plume/capture relationship was developed. By comparing the spatial relationship between contaminant plumes and hydraulic capture frequency, an index of relative protectiveness is developed and the results posted on the combined plume/capture plan view map. Areas exhibiting lesser degrees of river protection are identified for remedial process optimization actions to control plumes and prevent continuing discharge of Cr(VI) to the river.« less

Regenerating using aqueous cleaners with ozone and electrolysis

NASA Technical Reports Server (NTRS)

Mcginness, Michael P.

1994-01-01

A new process converts organic oil and grease contaminates in used water based cleaners into synthetic surfactants. This permits the continued use of a cleaning solution long after it would have been dumped using previously known methods. Since the organic soils are converted from contaminates to cleaning compounds the need for frequent bath dumps is totally eliminated. When cleaning solutions used in aqueous cleaning systems are exhausted and ready for disposal, they will always contain the contaminates removed from the cleaned parts and drag-in from prior cleaning steps. Even when the cleaner is biodegradable these contaminants will frequently cause the waste cleaning solution to be a hazardous waste. Chlorinated solvents are rapidly being replaced by aqueous cleaners to avoid the new ozone-depletion product-labeling-law. Many industry standard halocarbon based solvents are being completely phased out of production, and their prices have nearly tripled. Waste disposal costs and cradle-to-grave liability are also major concerns for industry today. This new process reduces the amount of water and chemicals needed to maintain the cleaning process. The cost of waste disposal is eliminated because the water and cleaning compounds are reused. Energy savings result by eliminating the need for energy currently used to produce and deliver fresh water and chemicals as well as the energy used to treat and destroy the waste from the existing cleaning processes. This process also allows the cleaning bath to be maintained at the peak performance of a new bath resulting in decreased cycle times and decreased energy consumption needed to clean the parts. This results in a more efficient and cost effective cleaning process.

Combining sieving and washing, a way to treat MSWI boiler fly ash.

PubMed

De Boom, Aurore; Degrez, Marc

2015-05-01

Municipal Solid Waste Incineration (MSWI) fly ashes contain some compounds that could be extracted and valorised. A process based on wet sieving and washing steps has been developed aiming to reach this objective. Such unique combination in MSWI fly ash treatment led to a non-hazardous fraction from incineration fly ashes. More specifically, MSWI Boiler Fly Ash (BFA) was separately sampled and treated. The BFA finer particles (13wt%) were found to be more contaminated in Pb and Zn than the coarser fractions. After three washing steps, the coarser fractions presented leaching concentrations acceptable to landfill for non-hazardous materials so that an eventual subsequent valorisation may be foreseen. At the contrary, too much Pb leached from the finest particles and this fraction should be further treated. Wet sieving and washing permit thus to reduce the leachability of MSWI BFA and to concentrate the Pb and Zn contamination in a small (in particle size and volume) fraction. Such combination would therefore constitute a straightforward and efficient basis to valorise coarse particles from MSWI fly ashes. Copyright © 2015 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, A.S.C.

The evaluation addresses the waste reduction/pollution prevention and economic issues involved in replacing chromated copper arsenate (CCA) with ammoniacal copper/quaternary ammonium (ACQ) as a way to preserve wood. The most obvious pollution prevention benefit gained by using ACQ is eliminating the use of arsenic and chromium, both of which generate hazardous wastes and a risk of contaminating the environment via chemical spills. Because most treatment plants are self-contained in that they reuse all wastewater produced within the plant and on the drip pads, no liquid waste problems were addressed for either the CCA or the ACQ treating process. The ACQmore » system generates more air pollution than does the CCA system, mainly as ammonia (NH3). For a plant with an annual production of 1 million cu ft (or about 20 million board feet), 90,000 lb of NH3 would be released per year from the ACQ treatment operations and the ACQ-treated wood. The treated wood, after being transferred from the drip pads to the outside storage yard, could become a major source of contamination.« less

Comparison of the efficacy of a hydrogen peroxide dry-mist disinfection system and sodium hypochlorite solution for eradication of Clostridium difficile spores.

PubMed

Barbut, F; Menuet, D; Verachten, M; Girou, E

2009-06-01

To compare a hydrogen peroxide dry-mist system and a 0.5% hypochlorite solution with respect to their ability to disinfect Clostridium difficile-contaminated surfaces in vitro and in situ. Prospective, randomized, before-after trial. Two French hospitals affected by C. difficile. In situ efficacy of disinfectants was assessed in rooms that had housed patients with C. difficile infection. A prospective study was performed at 2 hospitals that involved randomization of disinfection processes. When a patient with C. difficile infection was discharged, environmental contamination in the patient's room was evaluated before and after disinfection. Environmental surfaces were sampled for C. difficile by use of moistened swabs; swab samples were cultured on selective plates and in broth. Both disinfectants were tested in vitro with a spore-carrier test; in this test, 2 types of material, vinyl polychloride (representative of the room's floor) and laminate (representative of the room's furniture), were experimentally contaminated with spores from 3 C. difficile strains, including the epidemic clone ribotype 027-North American pulsed-field gel electrophoresis type 1. There were 748 surface samples collected (360 from rooms treated with hydrogen peroxide and 388 from rooms treated with hypochlorite). Before disinfection, 46 (24%) of 194 samples obtained in the rooms randomized to hypochlorite treatment and 34 (19%) of 180 samples obtained in the rooms randomized to hydrogen peroxide treatment showed environmental contamination. After disinfection, 23 (12%) of 194 samples from hypochlorite-treated rooms and 4 (2%) of 180 samples from hydrogen peroxide treated rooms showed environmental contamination, a decrease in contamination of 50% after hypochlorite decontamination and 91% after hydrogen peroxide decontamination (P < .005). The in vitro activity of 0.5% hypochlorite was time dependent. The mean (+/-SD) reduction in initial log(10) bacterial count was 4.32 +/- 0.35 log(10) colony-forming units after 10 minutes of exposure to hypochlorite and 4.18 +/- 0.8 log(10) colony-forming units after 1 cycle of hydrogen peroxide decontamination. In situ experiments indicate that the hydrogen peroxide dry-mist disinfection system is significantly more effective than 0.5% sodium hypochlorite solution at eradicating C. difficile spores and might represent a new alternative for disinfecting the rooms of patients with C. difficile infection.

Installation-Restoration Program environmental-technology development. Task order 3. Use of activated carbon for treatment of explosives-contaminated ground water at the Badger Army Ammunition Plant (BAAP). Final report Jun 88-Aug 89

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wujcik, W.J.; Lowe, W.L.; Marks, P.J.

1989-08-01

The United States Army operates explosives manufacturing plants to produce various forms of explosives used in military ordnance. Manufacturing activities at such plants result in the production of organic wastewaters that contain both explosive residues and other organic chemicals. Several treatment technologies have been developed to treat these wastewaters for final discharge. Past waste handling practices at explosives manufacturing plants commonly included the use of the unlined lagoons or pits for containing process wastewaters. As a result of these past practices, some explosives residues may leach through the soil and contaminated groundwater. Therefore, the treatment of contaminated groundwater may bemore » required.« less

Longitudinal analysis of bioaccumulative contaminants in freshwater fishes

USGS Publications Warehouse

Sun, Jielun; Kim, Y.; Schmitt, C.J.

2003-01-01

The National Contaminant Biomonitoring Program (NCBP) was initiated in 1967 as a component of the National Pesticide Monitoring program. It consists of periodic collection of freshwater fish and other samples and the analysis of the concentrations of persistent environmental contaminants in these samples. For the analysis, the common approach has been to apply the mixed two-way ANOVA model to combined data. A main disadvantage of this method is that it cannot give a detailed temporal trend of the concentrations since the data are grouped. In this paper, we present an alternative approach that performs a longitudinal analysis of the information using random effects models. In the new approach, no grouping is needed and the data are treated as samples from continuous stochastic processes, which seems more appropriate than ANOVA for the problem.

Vapor phase elemental sulfur amendment for sequestering mercury in contaminated soil

DOEpatents

Looney, Brian B.; Denham, Miles E.; Jackson, Dennis G.

2014-07-08

The process of treating elemental mercury within the soil is provided by introducing into the soil a heated vapor phase of elemental sulfur. As the vapor phase of elemental sulfur cools, sulfur is precipitated within the soil and then reacts with any elemental mercury thereby producing a reaction product that is less hazardous than elemental mercury.

Evaluating impacts of pulp and paper mill process changes on bioactive contaminant loading to the St. Louis River, Duluth, MN

EPA Science Inventory

Past in vivo and in vitro studies have found estrogenic and aryl hydrocarbon receptor (AhR)-mediated bioactivities associated with final treated effluent from a wastewater treatment plant (WWTP) discharging to the St. Louis River Area of Concern near Duluth, MN, USA. A long-stand...

Multi-Objective Optimization of an In situ Bioremediation Technology to Treat Perchlorate-Contaminated Groundwater

EPA Science Inventory

The presentation shows how a multi-objective optimization method is integrated into a transport simulator (MT3D) for estimating parameters and cost of in-situ bioremediation technology to treat perchlorate-contaminated groundwater.

Pathogenesis of Infection by Clinical and Environmental Strains of Vibrio vulnificus in Iron-Dextran-Treated Mice

PubMed Central

Starks, Angela M.; Schoeb, Trenton R.; Tamplin, Mark L.; Parveen, Salina; Doyle, Thomas J.; Bomeisl, Philip E.; Escudero, Gloria M.; Gulig, Paul A.

2000-01-01

Vibrio vulnificus is an opportunistic pathogen that contaminates oysters harvested from the Gulf of Mexico. In humans with compromising conditions, especially excess levels of iron in plasma and tissues, consumption of contaminated seafood or exposure of wounds to contaminated water can lead to systemic infection and disfiguring skin infection with extremely high mortality. V. vulnificus-associated diseases are noted for the rapid replication of the bacteria in host tissues, with extensive tissue damage. In this study we examined the virulence attributes of three virulent clinical strains and three attenuated oyster or seawater isolates in mouse models of systemic disease. All six V. vulnificus strains caused identical skin lesions in subcutaneously (s.c.) inoculated iron dextran-treated mice in terms of numbers of recovered CFU and histopathology; however, the inocula required for identical frequency and magnitude of infection were at least 350-fold higher for the environmental strains. At lethal doses, all strains caused s.c. skin lesions with extensive edema, necrosis of proximate host cells, vasodilation, and as many as 108 CFU/g, especially in perivascular regions. These data suggest that the differences between these clinical and environmental strains may be related to growth in the host or susceptibility to host defenses. In non-iron dextran-treated mice, strains required 105-fold-higher inocula to cause an identical disease process as with iron dextran treatment. These results demonstrate that s.c. inoculation of iron dextran-treated mice is a useful model for studying systemic disease caused by V. vulnificus. PMID:10992486

Low Quality Natural Gas Sulfur Removal and Recovery CNG Claus Sulfur Recovery Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klint, V.W.; Dale, P.R.; Stephenson, C.

1997-10-01

Increased use of natural gas (methane) in the domestic energy market will force the development of large non-producing gas reserves now considered to be low quality. Large reserves of low quality natural gas (LQNG) contaminated with hydrogen sulfide (H{sub 2}S), carbon dioxide (CO{sub 2}) and nitrogen (N) are available but not suitable for treatment using current conventional gas treating methods due to economic and environmental constraints. A group of three technologies have been integrated to allow for processing of these LQNG reserves; the Controlled Freeze Zone (CFZ) process for hydrocarbon / acid gas separation; the Triple Point Crystallizer (TPC) processmore » for H{sub 2}S / C0{sub 2} separation and the CNG Claus process for recovery of elemental sulfur from H{sub 2}S. The combined CFZ/TPC/CNG Claus group of processes is one program aimed at developing an alternative gas treating technology which is both economically and environmentally suitable for developing these low quality natural gas reserves. The CFZ/TPC/CNG Claus process is capable of treating low quality natural gas containing >10% C0{sub 2} and measurable levels of H{sub 2}S and N{sub 2} to pipeline specifications. The integrated CFZ / CNG Claus Process or the stand-alone CNG Claus Process has a number of attractive features for treating LQNG. The processes are capable of treating raw gas with a variety of trace contaminant components. The processes can also accommodate large changes in raw gas composition and flow rates. The combined processes are capable of achieving virtually undetectable levels of H{sub 2}S and significantly less than 2% CO in the product methane. The separation processes operate at pressure and deliver a high pressure (ca. 100 psia) acid gas (H{sub 2}S) stream for processing in the CNG Claus unit. This allows for substantial reductions in plant vessel size as compared to conventional Claus / Tail gas treating technologies. A close integration of the components of the CNG Claus process also allow for use of the methane/H{sub 2}S separation unit as a Claus tail gas treating unit by recycling the CNG Claus tail gas stream. This allows for virtually 100 percent sulfur recovery efficiency (virtually zero SO{sub 2} emissions) by recycling the sulfur laden tail gas to extinction. The use of the tail gas recycle scheme also deemphasizes the conventional requirement in Claus units to have high unit conversion efficiency and thereby make the operation much less affected by process upsets and feed gas composition changes. The development of these technologies has been ongoing for many years and both the CFZ and the TPC processes have been demonstrated at large pilot plant scales. On the other hand, prior to this project, the CNG Claus process had not been proven at any scale. Therefore, the primary objective of this portion of the program was to design, build and operate a pilot scale CNG Claus unit and demonstrate the required fundamental reaction chemistry and also demonstrate the viability of a reasonably sized working unit.« less

DEMONSTRATION BULLETIN: SOLIDIFICATION/STABILIZATION OF ORGANIC/INORGANIC CONTAMINANTS - SILICATE TECHNOLOGY CORPORATION

EPA Science Inventory

Silicate Technology Corporation's (STC's) technology for treating hazardous waste utilizes silicate compounds to stabilize organic and inorganic constituents in contaminated soils and sludges. STC has developed two groups of reagents: SOILSORB HM for treating wastes with inorgan...

Bioremediation of Petroleum and Radiological Contaminated Soils at the Savannah River Site: Laboratory to Field Scale Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

BRIGMON, ROBINL.

In the process of Savannah River Site (SRS) operations limited amounts of waste are generated containing petroleum, and radiological contaminated soils. Currently, this combination of radiological and petroleum contaminated waste does not have an immediate disposal route and is being stored in low activity vaults. SRS developed and implemented a successful plan for clean up of the petroleum portion of the soils in situ using simple, inexpensive, bioreactor technology. Treatment in a bioreactor removes the petroleum contamination from the soil without spreading radiological contamination to the environment. This bioreactor uses the bioventing process and bioaugmentation or the addition of themore » select hydrocarbon degrading bacteria. Oxygen is usually the initial rate-limiting factor in the biodegradation of petroleum hydrocarbons. Using the bioventing process allowed control of the supply of nutrients and moisture based on petroleum contamination concentrations and soil type. The results of this work have proven to be a safe and cost-effective means of cleaning up low level radiological and petroleum-contaminated soil. Many of the other elements of the bioreactor design were developed or enhanced during the demonstration of a ''biopile'' to treat the soils beneath a Polish oil refinery's waste disposal lagoons. Aerobic microorganisms were isolated from the aged refinery's acidic sludge contaminated with polycyclic aromatic hydrocarbons (PAHs). Twelve hydrocarbon-degrading bacteria were isolated from the sludge. The predominant PAH degraders were tentatively identified as Achromobacter, Pseudomonas Burkholderia, and Sphingomonas spp. Several Ralstonia spp were also isolated that produce biosurfactants. Biosurfactants can enhance bioremediation by increasing the bioavailability of hydrophobic contaminants including hydrocarbons. The results indicated that the diversity of acid-tolerant PAH-degrading microorganisms in acidic oil wastes may be much greater than previously demonstrated and they have numerous applications to environmental restoration. Twelve of the isolates were subsequently added to the bioreactor to enhance bioremediation. In this study we showed that a bioreactor could be bioaugmented with select bacteria to enhance bioremediation of petroleum-contaminated soils under radiological conditions.« less

Integration of Membrane Distillation with solar photo-Fenton for purification of water contaminated with Bacillus sp. and Clostridium sp. spores.

PubMed

Ruiz-Aguirre, A; Polo-López, M I; Fernández-Ibáñez, P; Zaragoza, G

2017-10-01

Although Membrane Distillation (MD) has been extensively studied for desalination, it has other applications like removing all kinds of solutes from water and concentrating non-volatile substances. MD offers the possibility of producing a clean stream while concentrating valuable compounds from waste streams towards their recovery, or emerging contaminants and pathogens present in wastewater in order to facilitate their chemical elimination. This paper analyses the elimination of bacterial spores from contaminated water with MD and the role of MD in the subsequent treatment of the concentrate with photo-Fenton process. The experiments were performed at Plataforma Solar de Almería (PSA) using a plate and frame bench module with a Permeate Gap Membrane Distillation (PGMD) configuration. Tests were done for two different kinds of spores in two different water matrixes: distilled water with 3.5wt% of sea salts contaminated with spores of Bacillus subtilis (B. subtilis) and wastewater after a secondary treatment and still contaminated with Clostridium sp. spores. An analysis of the permeate was performed in all cases to determine its purity, as well as the concentrated stream and its further treatment in order to assess the benefits of using MD. Results showed a permeate free of spores in all the cases, demonstrating the viability of MD to treat biological contaminated wastewater for further use in agriculture. Moreover, the results obtained after treating the concentrate with photo-Fenton showed a shorter treatment time for the reduction of the spore concentration in the water than that when only photo-Fenton was used. Copyright © 2017 Elsevier B.V. All rights reserved.

Significance of treated agrowaste residue and autochthonous inoculates (Arbuscular mycorrhizal fungi and Bacillus cereus) on bacterial community structure and phytoextraction to remediate soils contaminated with heavy metals.

PubMed

Azcón, Rosario; Medina, Almudena; Roldán, Antonio; Biró, Borbála; Vivas, Astrid

2009-04-01

In this study, we analyzed the impact of treatments such as Aspergillus niger-treated sugar beet waste (SB), PO4(3-) fertilization and autochthonous inoculants [arbuscular mycorrhizal (AM) fungi and Bacillus cereus], on the bacterial community structure in a soils contaminated with heavy metals as well as, the effectiveness on plant growth (Trifolium repens). The inoculation with AM fungi in SB amended soil, increased plant growth similarly to PO4(3-) addition, and both treatments matched in P acquisition but bacterial biodiversity estimated by denaturing gradient gel electrophoresis of amplified 16S rDNA sequences, was more stimulated by the presence of the AM fungus than by PO4(3-) fertilization. The SB amendment plus AM inoculation increased the microbial diversity by 233% and also changed (by 215%) the structure of the bacterial community. The microbial inoculants and amendment used favoured plant growth and the phytoextraction process and concomitantly modified bacterial community in the rhizosphere; thus they can be used for remediation. Therefore, the understanding of such microbial ecological aspects is important for phytoremediation and the recovery of contaminated soils.

METHODS FOR MONITORING PUMP-AND-TREAT PERFORMANCE

EPA Science Inventory

Since the 1980s, numerous pump-and-treat systems have been constructed to: (1) hydraulically contain contaminated ground water, and/or (2) restore ground-water quality to meet a desired standard such as background quality or Maximum Contaminant Level (MCL) concentrations for drin...

Protecting Lake Ontario - Treating Wastewater from the Remediated Low-Level Radioactive Waste Management Facility - 13227

DOE Office of Scientific and Technical Information (OSTI.GOV)

Freihammer, Till; Chaput, Barb; Vandergaast, Gary

2013-07-01

The Port Granby Project is part of the larger Port Hope Area Initiative, a community-based program for the development and implementation of a safe, local, long-term management solution for historic low level radioactive waste (LLRW) and marginally contaminated soils (MCS). The Port Granby Project involves the relocation and remediation of up to 0.45 million cubic metres of such waste from the current Port Granby Waste Management Facility located in the Municipality of Clarington, Ontario, adjacent to the shoreline of Lake Ontario. The waste material will be transferred to a new suitably engineered Long-Term Waste Management Facility (LTWMF) to be locatedmore » inland approximately 700 m from the existing site. The development of the LTWMF will include construction and commissioning of a new Wastewater Treatment Plant (WWTP) designed to treat wastewater consisting of contaminated surface run off and leachate generated during the site remediation process at the Port Granby Waste Management Facility as well as long-term leachate generated at the new LTWMF. Numerous factors will influence the variable wastewater flow rates and influent loads to the new WWTP during remediation. The treatment processes will be comprised of equalization to minimize impacts from hydraulic peaks, fine screening, membrane bioreactor technology, and reverse osmosis. The residuals treatment will comprise of lime precipitation, thickening, dewatering, evaporation and drying. The distribution of the concentration of uranium and radium - 226 over the various process streams in the WWTP was estimated. This information was used to assess potential worker exposure to radioactivity in the various process areas. A mass balance approach was used to assess the distribution of uranium and radium - 226, by applying individual contaminant removal rates for each process element of the WTP, based on pilot scale results and experience-based assumptions. The mass balance calculations were repeated for various flow and load scenarios. (authors)« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szescody, James E.; Moore, Robert C.; Rigali, Mark J.

The Old Rifle Site is a former vanadium and uranium ore-processing facility located adjacent to the Colorado River and approximately 0.3 miles east of the city of Rifle, CO. The former processing facilities have been removed and the site uranium mill tailings are interned at a disposal cell north of the city of Rifle. However, some low level remnant uranium contamination still exists at the Old Rifle site. In 2002, the United States Nuclear Regulatory Commission (US NRC) concurred with United States Department of Energy (US DOE) on a groundwater compliance strategy of natural flushing with institutional controls to decreasemore » contaminant concentrations in the aquifer. In addition to active monitoring of contaminant concentrations, the site is also used for DOE Legacy Management (LM) and other DOE-funded small-scale field tests of remediation technologies. The purpose of this laboratory scale study was to evaluate the effectiveness of a hydroxyapatite (Ca 10(PO 4) 6(OH) 2) permeable reactive barrier and source area treatment in Old Rifle sediments. Phosphate treatment impact was evaluated by comparing uranium leaching and surface phase changes in untreated to PO 4-treated sediments. The impact of the amount of phosphate precipitation in the sediment on uranium mobility was evaluated with three different phosphate loadings. A range of flow velocity and uranium concentration conditions (i.e., uranium flux through the phosphate-treated sediment) was also evaluated to quantify the uranium uptake mass and rate by the phosphate precipitate.« less

Reaction of the lateral periodontium of dogs' teeth to contaminated and noncontaminated perforations filled with mineral trioxide aggregate.

PubMed

Holland, Roberto; Bisco Ferreira, Luciana; de Souza, Valdir; Otoboni Filho, José Arlindo; Murata, Sueli Satomi; Dezan, Eloi

2007-10-01

It has been shown that the mineral trioxide aggregate (MTA) used to seal lateral/furcal perforations stimulates the deposition of newly formed cementum. Nevertheless, when the site of the perforation is contaminated, the healing process might occur under less favorable conditions. This study evaluated the repair healing process of noncontaminated and contaminated lateral perforations filled with MTA and the effect of previously filling the contaminated perforations with a bactericidal agent. Thirty lateral root perforations were prepared in endodontically treated dog's teeth, thus forming 3 groups with 10 specimens each. In group 1 the perforations were immediately sealed with MTA. In group 2 the perforations were left open for 7 days and thereafter sealed with MTA. In group 3 the perforations were left open for 7 days, filled temporarily with a calcium hydroxide-based paste for 14 days, and then sealed with MTA. The animals were killed after 90 days, and the pieces were prepared for histomorphologic and histomicrobiologic evaluations. The statistical analysis showed that group 1 had significantly better repair than groups 2 (P < .05) and 3 (P < .05), which validates the superior results obtained when MTA was immediately used to seal root perforations. Groups 2 and 3 had statistically similar repair to each other (P > .05). There were a larger number of cases of complete or partial biologic seal in group 1 compared with the contaminated groups. It might be concluded that the lateral root perforations sealed with MTA after contamination presented worse repair than the noncontaminated, immediately sealed perforations. The temporary filling with a bactericidal agent (calcium hydroxide-based paste) did not improve the repair of perforations exposed to contamination, and the contaminated groups presented similar results to each other.

CONTAMINANTS AND REMEDIAL OPTIONS AT PESTICIDE SITES

EPA Science Inventory

Many types of soils, sediments, and sludges are contaminated with a wide variety of pesticides. ite-specific characteristics such as volume to be treated, extent of contamination, and applicable cleanup goals differ greatly, and contaminant toxicity, migration pathways, persisten...

Remediation of Groundwater Contaminated by Nuclear Waste

NASA Astrophysics Data System (ADS)

Parker, Jack; Palumbo, Anthony

2008-07-01

A Workshop on Accelerating Development of Practical Field-Scale Bioremediation Models; An Online Meeting, 23 January to 20 February 2008; A Web-based workshop sponsored by the U.S. Department of Energy Environmental Remediation Sciences Program (DOE/ERSP) was organized in early 2008 to assess the state of the science and knowledge gaps associated with the use of computer models to facilitate remediation of groundwater contaminated by wastes from Cold War era nuclear weapons development and production. Microbially mediated biological reactions offer a potentially efficient means to treat these sites, but considerable uncertainty exists in the coupled biological, chemical, and physical processes and their mathematical representation.

Solidification as low cost technology prior to land filling of industrial hazardous waste sludge.

PubMed

El-Sebaie, O; Ahmed, M; Ramadan, M

2000-01-01

The aim of this study is to stabilize and solidify two different treated industrial hazardous waste sludges, which were selected from factories situated close to Alexandria. They were selected to ensure their safe transportation and landfill disposal by reducing their potential leaching of hazardous elements, which represent significant threat to the environment, especially the quality of underground water. The selected waste sludges have been characterized. Ordinary Portland Cement (OPC), Cement Kiln Dust (CKD) from Alexandria Portland Cement Company, and Calcium Sulphate as a by-product from the dye industry were used as potential solidification additives to treat the selected treated waste sludges from tanning and dyes industry. Waste sludges as well as the solidified wastes have been leach-tested, using the General Acid Neutralization Capacity (GANC) procedure. Concentration of concerning metals in the leachates was determined to assess changes in the mobility of major contaminants. The treated tannery waste sludge has an acid neutralization capacity much higher than that of the treated dyes waste sludge. Experiment results demonstrated the industrial waste sludge solidification mix designs, and presented the reduction of contaminant leaching from two types of waste sludges. The main advantages of solidification are that it is simple and low cost processing which includes readily available low cost solidification additives that will convert industrial hazardous waste sludges into inert materials.

Importance of microscopy in durability studies of solidified and stabilized contaminated soils

USGS Publications Warehouse

Klich, I.; Wilding, L.P.; Drees, L.R.; Landa, E.R.

1999-01-01

Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical, thermal, or biological means. Despite the increased use of S/S technologies, little research has been conducted on the weathering and degradation of solidified and stabilized wastes once the treated materials have been buried. Published data to verify the performance and durability of landfilled treated wastes over time are rare. In this preliminary study, optical and electron microscopy (scanning electron microscopy [SEM], transmission electron microscopy [TEM] and electron probe microanalyses [EPMA]) were used to evaluate weathering features associated with metal-bearing contaminated soil that had been solidified and stabilized with Portland cement and subsequently buried on site, stored outdoors aboveground, or achieved in a laboratory warehouse for up to 6 yr. Physical and chemical alteration processes identified include: freeze-thaw cracking, cracking caused by the formation of expansive minerals such as ettringite, carbonation, and the movement of metals from waste aggregates into the cement micromass. Although the extent of degradation after 6 yr is considered slight to moderate, results of this study show that the same environmental concerns that affect the durability of concrete must be considered when evaluating the durability and permanence of the solidification and stabilization of contaminated soils with cement. In addition, such evaluations cannot be based on leaching and chemical analyses alone. The use of all levels of microscopic analyses must be incorporated into studies of the long-term performance of S/S technologies.Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical, thermal, or biological means. Despite the increased use of S/S technologies, little research has been conducted on the weathering and degradation of solidified and stabilized wastes once the treated materials have been buried. Published data to verify the performance and durability of landfilled treated wastes over time are rare. In this preliminary study, optical and electron microscopy (scanning electron microscopy [SEM], transmission electron microscopy [TEM] and electron probe microanalyses [EPMA]) were used to evaluate weathering features associated with metal-bearing contaminated soil that had been solidified and stabilized with Portland cement and subsequently buried on site, stored outdoors aboveground, or archived in a laboratory, warehouse for up to 6 yr. Physical and chemical alteration processes identified include: freeze-thaw cracking, cracking caused by the formation of expansive minerals such as ettringite, carbonation, and the movement of metals from waste aggregates into the cement micromass. Although the extent of degradation after 6 yr is considered slight to moderate, results of this study show that the same environmental concerns that affect the durability of concrete must be considered when evaluating the durability and permanence of the solidification and stabilization of contaminated soils with cement. In addition, such evaluations cannot be based on leaching and chemical analyses alone. The use of all levels of microscopic analyses must be incorporated into studies of the long-term performance of S/S technologies.

Remediation of Mercury-Contaminated Storm Sewer Sediments from the West End Mercury Area at the Y-12 National Security Complex in Oak Ridge, Tennessee - 12061

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tremaine, Diana; Douglas, Steven G.

2012-07-01

The Y-12 National Security Complex in Oak Ridge, TN has faced an ongoing challenge from mercury entrapped in soils beneath and adjacent to buildings, storm sewers, and process pipelines. Previous actions to reduce the quantity and/or mobilization of mercury-contaminated media have included plugging of building floor drains, cleaning of sediment and sludge from sumps, manholes, drain lines, and storm sewers, lining/relining of storm sewers and replacement of a portion of the storm sewer trunk line, re-routing and removal of process piping, and installation of the Central Mercury Treatment System to capture and treat contaminated sump water. Despite the success ofmore » these actions, mercury flux in the storm sewer out-falls that discharge to Upper East Fork Poplar Creek (UEFPC) continues to pose a threat to long-term water quality. A video camera survey of the storm sewer network revealed several sections of storm sewer that had large cracks, separations, swells, and accumulations of sediment/sludge and debris. The selected remedy was to clean and line the sections of storm sewer pipe that were determined to be primary contributors to the mercury flux in the storm sewer out-falls. The project, referred to as the West End Mercury Area (WEMA) Storm Sewer Remediation Project, included cleaning sediment and debris from over 2,460 meters of storm sewer pipe followed by the installation of nearly 366 meters of cure-in-place pipe (CIPP) liner. One of the greatest challenges to the success of this project was the high cost of disposal associated with the mercury-contaminated sludge and wastewater generated from the storm sewer cleaning process. A contractor designed and operated an on-site wastewater pre-treatment system that successfully reduced mercury levels in 191 cubic meters of sludge to levels that allowed it to be disposed at Nevada Nuclear Security Site (NNSS) disposal cell as a non-hazardous, low-level waste. The system was also effective at pre-treating over 1,514,000 liters of wastewater to levels that met the waste acceptance criteria for the on-site West End [wastewater] Treatment Facility (WETF). This paper describes the storm sewer cleaning and lining process and the methods used to process the mercury-contaminated sludge and wastewater, as well as several 'lessons learned' that would be relevant to any future projects involving storm sewer cleaning and debris remediation. (authors)« less

Regulatory and Technical Issues Concerning the Detection and Treatment of NDMA-Contaminated Groundwater at NASA WSTF

NASA Technical Reports Server (NTRS)

Wiebe, D. T.; Zigmond, M. J.; Tufts, C. A.

2002-01-01

The National Aeronautics and Space Administration (NASA) White Sands Test Facility (WSTF) was established in 1963 primarily to provide rocket engine testing services for several NASA programs. The groundwater underlying the site has been contaminated as a result of historical operations. Groundwater contaminants include several volatile organic compounds (VOCs) and two semi-volatile compounds: N-nitrosodimethylamine (NDMA) and N-nitrodimethylamine (DMN). This paper discusses some of the technical, analytical, regulatory, and health risk issues associated with the contaminant plume. The plume has moved approximately 2.5 miles downgradient of the facility industrial boundary, with evidence of continued migration. As a result, NASA has proposed a pump and treat system using air strippers and ultraviolet (UV) oxidation to stabilize future movement of the contaminant plume. The system has been designed to treat 1,076 gallons (4,073 liters) per minute, with provisions for future expansion. The UV oxidation process was selected to treat NDMA-contaminated groundwater based on successes at other NDMA-contaminated sites. Bench- and pilot-scale testing of WSTF groundwater confirmed the ability of UV oxidation to destroy NDMA and generated sufficient data to design the proposed full-scale treatment system. NDMA is acutely toxic and is a probable human carcinogen. EPA-recommended health risk criteria for the residential consumption of NDMA/DMN-contaminated groundwater was used to determine that a 1.0 x 10(exp -6) excess cancer risk corresponds to 1.7 parts per trillion (ppt). EPA analytical methods are unable to detect NDMA and DMN in the low ppt range. EPA's current Appendix IX analytical method used to screen for NDMA, Method 8270, can detect NDMA only at levels that are orders of magnitude greater than the recommended health risk level. Additionally, EPA Method 607, the most sensitive EPA approved method, has a detection limit of 150 ppt. This corresponds to an excess cancer risk of 9.0 x 10(exp -5), which exceeds the State of New Mexico's water quality standard of a cancer risk less than 1 x 10(exp -5). The treatment system has been engineered to treat contaminated groundwater to levels significantly below the New Mexico standard. However, the inability of EPA-approved analytical methods to detect NDMA and DMN at low ppt levels, and to provide verification of compliance with the 1 x 10(exp -5) cancer risk, introduces a notable risk to the long-term operation of the system. WSTF has been working with Southwest Research Institute to develop a non-EPA analytical method that can achieve a reporting limit of 1 ppt, which corresponds to an excess cancer risk of 7.6 x 10(exp -7). WSTF is currently developing a proposal to obtain approval from the New Mexico Environment Department (NMED) of this non-EPA method.

EPA and USGS scientists conduct study to determine prevalence of newly-emerging contaminants in treated and untreated drinking water

EPA Pesticide Factsheets

Scientists from the EPA and USGS are collaborating on a research study to determine the presence of contaminants of emerging concern in treated and untreated drinking water collected from drinking water treatment plants.

Performance evaluation of cross-flow membrane system for wastewater reuse from the wood-panels industry.

PubMed

Dizge, Nadir

2014-01-01

The objectives of this investigation were to perform a series of lab-scale membrane separation experiments under various operating conditions to investigate the performance behaviour of nanofiltration membrane (NF 270) for wastewater reuse from the wood-panels industry. The operating condition effects, e.g. cross-flow velocity (CFV), trans membrane pressure (TMP) and temperature, on the permeate flux and contaminant rejection efficiency were investigated. Moreover, three different samples: (1) raw wastewater collected from the wood-panels industry; (2) ultrafiltration pre-treated wastewater (UF-NF); and (3) coagulation/flocculation pre-treated wastewater (CF-NF) were employed in this study. The UF-NF was proposed as a pre-treatment process because it could reduce the chemical oxygen demand (COD) effectively with lower energy consumption than CF-NF. The performance of NF 270 membrane was assessed by measurements of the many parameters (pH, conductivity, total dissolved solids, COD, suspended solids, total nitrogen, nitrite, nitrate, and total phosphate) under various operating conditions. It was noted that the contaminant rejection was affected by changing TMP and CFV. It was concluded that the purified water stream can be recycled into the process for water reuse or safely disposed to the river.

The phage‐driven microbial loop in petroleum bioremediation

PubMed Central

Rosenberg, Eugene; Bittan‐Banin, Gili; Sharon, Gil; Shon, Avital; Hershko, Galit; Levy, Itzik; Ron, Eliora Z.

2010-01-01

Summary During the drilling process and transport of crude oil, water mixes with the petroleum. At oil terminals, the water settles to the bottom of storage tanks. This drainage water is contaminated with emulsified oil and water‐soluble hydrocarbons and must be treated before it can be released into the environment. In this study, we tested the efficiency of a continuous flow, two‐stage bioreactor for treating drainage water from an Israeli oil terminal. The bioreactor removed all of the ammonia, 93% of the sulfide and converted 90% of the total organic carbon (TOC) into carbon dioxide. SYBR Gold staining indicated that reactor 1 contained 1.7 × 108 bacteria and 3.7 × 108 phages per millilitre, and reactor 2 contained 1.3 × 108 bacteria and 1.7 × 109 phages per millilitre. The unexpectedly high mineralization of TOC and high concentration of phage in reactor 2 support the concept of a phage‐driven microbial loop in the bioremediation of the drainage water. In general, application of this concept in bioremediation of contaminated water has the potential to increase the efficiency of processes. PMID:21255344

Treatability of volatile chlorinated hydrocarbon-contaminated soils of different textures along a vertical profile by mechanical soil aeration: A laboratory test.

PubMed

Ma, Yan; Shi, Yi; Hou, Deyi; Zhang, Xi; Chen, Jiaqi; Wang, Zhifen; Xu, Zhu; Li, Fasheng; Du, Xiaoming

2017-04-01

Mechanical soil aeration is a simple, effective, and low-cost soil remediation technology that is suitable for sites contaminated with volatile chlorinated hydrocarbons (VCHs). Conventionally, this technique is used to treat the mixed soil of a site without considering the diversity and treatability of different soils within the site. A laboratory test was conducted to evaluate the effectiveness of mechanical soil aeration for remediating soils of different textures (silty, clayey, and sandy soils) along a vertical profile at an abandoned chloro-alkali chemical site in China. The collected soils were artificially contaminated with chloroform (TCM) and trichloroethylene (TCE). Mechanical soil aeration was effective for remediating VCHs (removal efficiency >98%). The volatilization process was described by an exponential kinetic function. In the early stage of treatment (0-7hr), rapid contaminant volatilization followed a pseudo-first order kinetic model. VCH concentrations decreased to low levels and showed a tailing phenomenon with very slow contaminant release after 8hr. Compared with silty and sandy soils, clayey soil has high organic-matter content, a large specific surface area, a high clay fraction, and a complex pore structure. These characteristics substantially influenced the removal process, making it less efficient, more time consuming, and consequently more expensive. Our findings provide a potential basis for optimizing soil remediation strategy in a cost-effective manner. Copyright © 2016. Published by Elsevier B.V.

Bioremediation of poly-aromatic hydrocarbon (PAH)-contaminated soil by composting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loick, N.; Hobbs, P.J.; Hale, M.D.C.

2009-07-01

This paper presents a comprehensive and critical review of research on different co-composting approaches to bioremediate hydrocarbon contaminated soil, organisms that have been found to degrade PAHs, and PAH breakdown products. Advantages and limitations of using certain groups of organisms and recommended areas of further research effort are identified. Studies investigating the use of composting techniques to treat contaminated soil are broad ranging and differ in many respects, which makes comparison of the different approaches very difficult. Many studies have investigated the use of specific bio-additives in the form of bacteria or fungi with the aim of accelerating contaminant removal;more » however, few have employed microbial consortia containing organisms from both kingdoms despite knowledge suggesting synergistic relationships exist between them in contaminant removal. Recommendations suggest that further studies should attempt to systemize the investigations of composting approaches to bio-remediate PAH-contaminated soil, to focus on harnessing the biodegradative capacity of both bacteria and fungi to create a cooperative environment for PAH degradation, and to further investigate the array of PAHs that can be lost during the composting process by either leaching or volatilization.« less

Pilot-scale UV/H2O2 advanced oxidation process for municipal reuse water: Assessing micropollutant degradation and estrogenic impacts on goldfish (Carassius auratus L.).

PubMed

Shu, Zengquan; Singh, Arvinder; Klamerth, Nikolaus; McPhedran, Kerry; Bolton, James R; Belosevic, Miodrag; Gamal El-Din, Mohamed

2016-09-15

Low concentrations (ng/L-μg/L) of emerging micropollutant contaminants in municipal wastewater treatment plant effluents affect the possibility to reuse these waters. Many of those micropollutants elicit endocrine disrupting effects in aquatic organisms resulting in an alteration of the endocrine system. A potential candidate for tertiary municipal wastewater treatment of these micropollutants is ultraviolet (UV)/hydrogen peroxide (H2O2) as an advanced oxidation process (AOP) which was currently applied to treat the secondary effluent of the Gold Bar Wastewater Treatment Plant (GBWWTP) in Edmonton, AB, Canada. A new approach is presented to predict the fluence-based degradation rate constants (kf') of environmentally occurring micropollutants including carbamazepine [(0.87-1.39) × 10(-3) cm(2)/mJ] and 2,4-Dichlorophenoxyacetic acid (2,4-D) [(0.60-0.91) × 10(-3) cm(2)/mJ for 2,4-D] in a medium pressure (MP) UV/H2O2 system based on a previous bench-scale investigation. Rather than using removal rates, this approach can be used to estimate the performance of the MP UV/H2O2 process for degrading trace contaminants of concern found in municipal wastewater. In addition to the ability to track contaminant removal/degradation, evaluation of the MP UV/H2O2 process was also accomplished by identifying critical ecotoxicological endpoints (i.e., estrogenicity) of the treated wastewater. Using quantitative PCR, mRNA levels of estrogen-responsive (ER) genes ERα1, ERα2, ERβ1, ERβ2 and NPR as well as two aromatase encoding genes (CYP19a and CYP19b) in goldfish (Carassius auratus L.) were measured during exposure to the GBWWTP effluent before and after MP UV/H2O2 treatment (a fluence of 1000 mJ/cm(2) and 20 mg/L of H2O2) in spring, summer and fall. Elevated expression of estrogen-responsive genes in goldfish exposed to UV/H2O2 treated effluent (a 7-day exposure) suggested that the UV/H2O2 process may induce acute estrogenic disruption to goldfish principally because of the possible formation of various oxidation by-products. However, prolonged exposure of goldfish (60 days) in UV/H2O2 treated effluent showed a restoration trend of ER gene expressions, especially in the summer. Collectively, our findings provide valuable indications regarding the long-term in vivo assessment of the MP UV/H2O2 process for removing/degrading endocrine disrupting compounds detected in the municipal wastewater effluents. Copyright © 2016 Elsevier Ltd. All rights reserved.

A hybrid approach for treating fluorided water and biogeophysical monitoring of treatment processes

NASA Astrophysics Data System (ADS)

Singh, K. P.

2016-12-01

A laboratory experiment has been conducted for investigating the possibility of development of novel techniques for treating fluoride contamination and monitoring of physico-chemical alterations caused by biogeochemical processes in the media. In the present study, high adsorption capacity and ion-exchange property of natural zeolites have been utilized in treating fluoride contamination. The preset goals are achieved by designing and constructing experimental setup consisting of three columns, first one is filled with 450 ppm fluorided water prepared by dissolving sodium fluoride in deionized water, the second is filled with zeolite and fluorided water, and the third is filled with zeolite, fluorided water, sodium lactate and the bacterial seed. The first and the second columns were poisoned with sodium azide for preventing the growth of microorganisms. The self-potential (SP) signals associated with physico-chemical alterations in natural zeolite induced by biogeochemical processes are measured by using Cu-CuSO4 gel electrodes. Liquid-phase analysis of samples from column two and three show the reduced concentrations of fluoride and aluminum and it indicates the possibility of precipitation of insoluble aluminum fluoride. This is further confirmed by the presence of fluoride and aluminum in the solid samples as detected by energy dispersive X-ray analysis. The distinct SP of the order of -50 mV and 200 mV have been associated with biostimulated fluoride remediation and geochemical fluoride remediation processes respectively. Thus, there is a possibility of non-invasive monitoring of fluoride remediation processes driven by both microbes and chemical processes. It is found that after thirty-day nitrate and sulfate is introduced in column two due chemical interaction between water and natural zeolite. Furthermore, this study demonstrates that a hybrid approach, a combination of ion exchange and adsorption properties of natural zeolite and the bioremediation is more effective and less expensive than the chemical methodologies.

Assessing the Extent of Sediment Contamination Around Creosote-treated Pilings Through Chemical and Biological Analyses

NASA Astrophysics Data System (ADS)

Stefansson, E. S.

2008-12-01

Creosote is a common wood preservative used to treat marine structures, such as docks and bulkheads. Treated dock pilings continually leach polycyclic aromatic hydrocarbons (PAHs) and other creosote compounds into the surrounding water and sediment. Over time, these compounds can accumulate in marine sediments, reaching much greater concentrations than those in seawater. The purpose of this study was to assess the extent of creosote contamination in sediments, at a series of distances from treated pilings. Three pilings were randomly selected from a railroad trestle in Fidalgo Bay, WA and sediment samples were collected at four distances from each: 0 meters, 0.5 meters, 1 meter, and 2 meters. Samples were used to conduct two bioassays: an amphipod bioassay (Rhepoxynius abronius) and a sand dollar embryo bioassay. Grain size and PAH content (using a fluorometric method) were also measured. Five samples in the amphipod bioassay showed significantly lower effective survival than the reference sediment. These consisted of samples closest to the piling at 0 and 0.5 meters. One 0 m sample in the sand dollar embryo bioassay also showed a significantly lower percentage of normal embryos than the reference sediment. Overall, results strongly suggest that creosote-contaminated sediments, particularly those closest to treated pilings, can negatively affect both amphipods and echinoderm embryos. Although chemical data were somewhat ambiguous, 0 m samples had the highest levels of PAHs, which corresponded to the lowest average survival in both bioassays. Relatively high levels of PAHs were found as far as 2 meters away from pilings. Therefore, we cannot say how far chemical contamination can spread from creosote-treated pilings, and at what distance this contamination can still affect marine organisms. These results, as well as future research, are essential to the success of proposed piling removal projects. In addition to creosote-treated pilings, contaminated sediments must be removed and disposed of properly, in order to make future piling removals as effective and beneficial to ecosystem health as possible.

Evapotranspiration And Geochemical Controls On Groundwater Plumes At Arid Sites: Toward Innovative Alternate End-States For Uranium Processing And Tailings Facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Looney, Brian B.; Denham, Miles E.; Eddy-Dilek, Carol A.

2014-01-08

Management of legacy tailings/waste and groundwater contamination are ongoing at the former uranium milling site in Tuba City AZ. The tailings have been consolidated and effectively isolated using an engineered cover system. For the existing groundwater plume, a system of recovery wells extracts contaminated groundwater for treatment using an advanced distillation process. The ten years of pump and treat (P&T) operations have had minimal impact on the contaminant plume – primarily due to geochemical and hydrological limits. A flow net analysis demonstrates that groundwater contamination beneath the former processing site flows in the uppermost portion of the aquifer and exitsmore » the groundwater as the plume transits into and beneath a lower terrace in the landscape. The evaluation indicates that contaminated water will not reach Moenkopi Wash, a locally important stream. Instead, shallow groundwater in arid settings such as Tuba City is transferred into the vadose zone and atmosphere via evaporation, transpiration and diffuse seepage. The dissolved constituents are projected to precipitate and accumulate as minerals such as calcite and gypsum in the deep vadose zone (near the capillary fringe), around the roots of phreatophyte plants, and near seeps. The natural hydrologic and geochemical controls common in arid environments such as Tuba City work together to limit the size of the groundwater plume, to naturally attenuate and detoxify groundwater contaminants, and to reduce risks to humans, livestock and the environment. The technical evaluation supports an alternative beneficial reuse (“brownfield”) scenario for Tuba City. This alternative approach would have low risks, similar to the current P&T scenario, but would eliminate the energy and expense associated with the active treatment and convert the former uranium processing site into a resource for future employment of local citizens and ongoing benefit to the Native American Nations.« less

Effective reprocessing of reusable dispensers for surface disinfection tissues – the devil is in the details

PubMed Central

Kampf, Günter; Degenhardt, Stina; Lackner, Sibylle; Ostermeyer, Christiane

2014-01-01

Background: It has recently been reported that reusable dispensers for surface disinfection tissues may be contaminated, especially with adapted Achromobacter species 3, when products based on surface-active ingredients are used. Fresh solution may quickly become recontaminated if dispensers are not processed adequately. Methods: We evaluated the abilities of six manual and three automatic processes for processing contaminated dispensers to prevent recolonisation of a freshly-prepared disinfectant solution (Mikrobac forte 0.5%). Dispensers were left at room temperature for 28 days. Samples of the disinfectant solution were taken every 7 days and assessed quantitatively for bacterial contamination. Results: All automatic procedures prevented recolonisation of the disinfectant solution when a temperature of 60–70°C was ensured for at least 5 min, with or without the addition of chemical cleaning agents. Manual procedures prevented recontamination of the disinfectant solution when rinsing with hot water or a thorough cleaning step was performed before treating all surfaces with an alcohol-based disinfectant or an oxygen-releaser. Other cleaning and disinfection procedures, including the use of an alcohol-based disinfectant, did not prevent recolonisation. Conclusions: These results indicate that not all processes are effective for processing reusable dispensers for surface-disinfectant tissues, and that a high temperature during the cleaning step or use of a biofilm-active cleaning agent are essential. PMID:24653973

Mitigation of enniatins in edible fish tissues by thermal processes and identification of degradation products.

PubMed

Tolosa, J; Font, G; Mañes, J; Ferrer, E

2017-03-01

Emerging mycotoxins, such as enniatins and beauvericin, are common contaminants in vegetal matrices, but recently, the occurrence of mycotoxins in foodstuffs from animal origin has been also reported as they can be present in edible tissues of animals fed with contaminated feedstuffs. Sea bass, sea bream, Atlantic salmon and rainbow trout from aquaculture analyzed in the present survey showed contamination by emerging Fusarium mycotoxins enniatins (ENs). ENs were extracted from raw and cooked fish with acetonitrile and analyzed by Liquid Chromatography coupled to Mass Spectrometry. In this study, the stability of ENs was evaluated during food processing by the application of different cooking methods (broiling, boiling, microwaving and baking treatments). All treated samples showed a reduction in mycotoxin levels with different percentages depending on the type of EN and the fish species. Thus, the reduction obtained ranged from 30 to 100%. The thermal treatments have shown to be a good strategy to mitigate ENs content in edible fish tissues. On the other hand, some ENs degradation products originated during the application of thermal treatments were identified. Copyright © 2017 Elsevier Ltd. All rights reserved.

Study of evaporating the irradiated graphite in equilibrium low-temperature plasma

NASA Astrophysics Data System (ADS)

Bespala, E. V.; Novoselov, I. Yu.; Pavlyuk, A. O.; Kotlyarevskiy, S. G.

2018-01-01

The paper describes a problem of accumulation of irradiated graphite due to operation of uranium-graphite nuclear reactors. The main noncarbon contaminants that contribute to the overall activity of graphite elements are iso-topes 137Cs, 60Co, 90Sr, 36Cl, and 3H. A method was developed for processing of irradiated graphite ensuring the volu-metric decontamination of samples. The calculation results are presented for equilibrium composition of plasma-chemical reactions in systems "irradiated graphite-argon" and "irradiated graphite-helium" for a wide range of tem-peratures. The paper describes a developed mathematical model for the process of purification of a porous graphite surface treated by equilibrium low-temperature plasma. The simulation results are presented for the rate of sublimation of radioactive contaminants as a function of plasma temperature and plasma flow velocity when different plasma-forming gases are used. The extraction coefficient for the contaminant 137Cs from the outer side of graphite pores was calculated. The calculations demonstrated the advantages of using a lighter plasma forming gas, i.e., helium.

FIELD EVALUATION OF THE LIGNIN-DEGRADING FUNGUS PHANEROCHAETE SORDIDA TO TREAT CREOSOTE-CONTAMINATED SOIL

EPA Science Inventory

A field study to determine the ability of selected lignin-degrading fungi to remediate soil contaminated with creosote was performed at a wood-treating facility in south central Mississippi in the autumn of 1991. The effects of solid-phase bioremediation with Phanerochaete sordid...

PCE/TCE DEGRADATION USING MULCH BIOWALLS

EPA Science Inventory

A passive reactive barrier (Biowall) was installed at the OU-1 site at Altus Air Force Base, Oklahoma to treat TCE contamination in ground water from a landfill. Depth to ground water varies from 1.8 to 2.4 meters below land surface. To intercept and treat the plume of contamin...

Yellow phosphorus process to convert toxic chemicals to non-toxic products

DOEpatents

Chang, S.G.

1994-07-26

The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

Yellow phosphorus process to convert toxic chemicals to non-toxic products

DOEpatents

Chang, Shih-Ger

1994-01-01

The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O.sub.3, PO, PO.sub.2, etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like.

Woodchip-sulfur based heterotrophic and autotrophic denitrification (WSHAD) process for nitrate contaminated water remediation.

PubMed

Li, Rui; Feng, Chuanping; Hu, Weiwu; Xi, Beidou; Chen, Nan; Zhao, Baowei; Liu, Ying; Hao, Chunbo; Pu, Jiaoyang

2016-02-01

Nitrate contaminated water can be effectively treated by simultaneous heterotrophic and autotrophic denitrification (HAD). In the present study, woodchips and elemental sulfur were used as co-electron donors for HAD. It was found that ammonium salts could enhance the denitrifying activity of the Thiobacillus bacteria, which utilize the ammonium that is produced by the dissimilatory nitrate reduction to ammonium (DNRA) in the woodchip-sulfur based heterotrophic and autotrophic denitrification (WSHAD) process. The denitrification performance of the WSHAD process (reaction constants range from 0.05485 h(-1) to 0.06637 h(-1)) is better than that of sulfur-based autotrophic denitrification (reaction constants range from 0.01029 h(-1) to 0.01379 h(-1)), and the optimized ratio of woodchips to sulfur is 1:1 (w/w). No sulfate accumulation is observed in the WSHAD process and the alkalinity generated in the heterotrophic denitrification can compensate for alkalinity consumption by the sulfur-based autotrophic denitrification. The symbiotic relationship between the autotrophic and the heterotrophic denitrification processes play a vital role in the mixotrophic environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effectiveness of an anaerobic granular activated carbon fluidized-bed bioreactor to treat soil wash fluids: a proposed strategy for remediating PCP/PAH contaminated soils.

PubMed

Koran, K M; Suidan, M T; Khodadoust, A P; Sorial, G A; Brenner, R C

2001-07-01

An integrated system has been developed to remediate soils contaminated with pentachlorophenol (PCP) and polycyclic aromatic hydrocarbons (PAHs). This system involves the coupling of two treatment technologies, soil-solvent washing and anaerobic biotreatment of the extract. Specifically, this study evaluated the effectiveness of a granular activated carbon (GAC) fluidized-bed reactor to treat a synthetic-waste stream of PCP and four PAHs (naphthalene, acenaphthene, pyrene, and benzo(b)fluoranthene) under anaerobic conditions. This waste stream was intended to simulate the wash fluids from a soil washing process treating soils from a wood-preserving site. The reactor achieved a removal efficiency of greater than 99.8% for PCP with conversion to its dechlorination intermediates averaging 46.5%. Effluent, carbon extraction, and isotherm data also indicate that naphthalene and acenaphthene were removed from the liquid phase with efficiencies of 86 and 93%, respectively. Effluent levels of pyrene and benzo(b)fluoranthene were extremely low due to the high-adsorptive capacity of GAC for these compounds. Experimental evidence does not suggest that the latter two compounds were biochemically transformed within the reactor.

Environmental Program

NASA Technical Reports Server (NTRS)

Fischer, Holger

2009-01-01

NASA's White Sands Test Facility has six core environmental compliance capabilities: remote hazardous testing of reactive, explosive and toxic materials and fluids; hypergolic fluids materials and systems testing; oxygen materials and system testing; hypervelocity impact testing; flight hardware processing; and, propulsion testing. The facility's permit status and challenges are reviewed. Historic operations and practices dating from the 1960s through the early 1980s resulted in contamination of the facility's groundwater. An environmental restoration effort has been employed to protect public health and the health of the workforce. The restoration seeks to properly handle hazardous materials and waste processes; determine the nature and extent of the contamination; stop the migration of contaminated groundwater; stabilize the plume front which has been assessed as the greatest risk to public health; and, clean-up the environment to restore it to preexisting conditions. The Plume Front Treatment System is operational and seeks to stop the westward movement of the plume to protect drinking water and irrigation well. Specifically, the treatment system will extract contaminated water from the aquifer, remove chemical using the best available technology, and return (inject) the treated water back to the aquifer. The Mid-Plume Interception Treatment System also seeks to stop the migration of containment, as well as to evaluate new technologies to accelerate cleanup, such as bioremediation.

Contaminant treatment method

DOEpatents

Shapiro, Andrew Philip; Thornton, Roy Fred; Salvo, Joseph James

2003-01-01

The present invention provides a method for treating contaminated media. The method comprises introducing remediating ions consisting essentially of ferrous ions, and being peroxide-free, in the contaminated media; applying a potential difference across the contaminated media to cause the remediating ions to migrate into contact with contaminants in the contaminated media; chemically degrading contaminants in the contaminated media by contact with the remediating ions; monitoring the contaminated media for degradation products of the contaminants; and controlling the step of applying the potential difference across the contaminated media in response to the step of monitoring.

Superfund record of decision (EPA Region 10): McCormick and Baxter Creosoting Company, Portland Plant, Portland, OR, March 29, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-08-01

The decision document presents the selected final remedial actions for the McCormick and Baxter Creosoting Company, Portland Plant site (McCormick and Baxter or site) located in Portland, Oregon. The selected remedy is a series of remedial actions that address the principal threats at the site by treating the most highly contaminated soil, extracting nonaqueous phase liquid (NAPL) and treating contaminated groundwater, and capping the most highly contaminated sediment.

Decontamination of Petroleum-Contaminated Soils Using The Electrochemical Technique: Remediation Degree and Energy Consumption.

PubMed

Streche, Constantin; Cocârţă, Diana Mariana; Istrate, Irina-Aura; Badea, Adrian Alexandru

2018-02-19

Currently, there are different remediation technologies for contaminated soils, but the selection of the best technology must be not only the treatment efficiency but also the energy consumption (costs) during its application. This paper is focused on assessing energy consumption related to the electrochemical treatment of polluted soil with petroleum hydrocarbons. In the framework of a research project, two types of experiments were conducted using soil that was artificially contaminated with diesel fuel at the same level of contamination. The experimental conditions considered for each experiment were: different amounts of contaminated soils (6 kg and 18 kg, respectively), the same current intensity level (0.25A and 0.5A), three different contamination degrees (1%, 2.5% and 5%) and the same time for application of the electrochemical treatment. The remediation degree concerning the removal of petroleum hydrocarbons from soil increased over time by approximately 20% over 7 days. With regard to energy consumption, the results revealed that with an increase in the quantity of treated soil of approximately three times, the specific energy consumption decreased from 2.94 kWh/kg treated soil to 1.64 kWh/kg treated soil.

Perchlorate and nitrate treatment by ion exchange integrated with biological brine treatment.

PubMed

Lehman, S Geno; Badruzzaman, Mohammad; Adham, Samer; Roberts, Deborah J; Clifford, Dennis A

2008-02-01

Groundwater contaminated with perchlorate and nitrate was treated in a pilot plant using a commercially available ion exchange (IX) resin. Regenerant brine concentrate from the IX process, containing high perchlorate and nitrate, was treated biologically and the treated brine was reused in IX resin regeneration. The nitrate concentration of the feed water determined the exhaustion lifetime (i.e., regeneration frequency) of the resin; and the regeneration condition was determined by the perchlorate elution profile from the exhausted resin. The biological brine treatment system, using a salt-tolerant perchlorate- and nitrate-reducing culture, was housed in a sequencing batch reactor (SBR). The biological process consistently reduced perchlorate and nitrate concentrations in the spent brine to below the treatment goals of 500 microg ClO4(-)/L and 0.5mg NO3(-)-N/L determined by equilibrium multicomponent IX modeling. During 20 cycles of regeneration, the system consistently treated the drinking water to below the MCL of nitrate (10 mgNO3(-)-N/L) and the California Department of Health Services (CDHS) notification level of perchlorate (i.e., 6 microg/L). A conceptual cost analysis of the IX process estimated that perchlorate and nitrate treatment using the IX process with biological brine treatment to be approximately 20% less expensive than using the conventional IX with brine disposal.

The health and technological implications of a better control of neoformed contaminants by the food industry.

PubMed

Birlouez-Aragon, I; Morales, F; Fogliano, V; Pain, J-P

2010-06-01

The recent discovery of the presence of variable amounts of the carcinogenic compound acrylamide in a wide range of severely heat-treated food products, such as fried potatoes, biscuits, bread and coffee or malt, as a result of the heat process, has induced an important research in the area of the Maillard reaction in food. The interaction between a specific food composition and the heat process applied results in the development of complex oxidation and glycation reactions, which give rise to a mixture of flavoured compounds and possible neoformed contaminants (NFC). Recommendations by the European Commission aim at monitoring the content of major NFC, such as acrylamide and furan, in a list of food products commercialized in Europe. On the other hand, the Commission for European Normalization (CEN) has created recently a new workgroup (WG13) responsible for normalization of analytical method for NFC assessment. The European collective research ICARE was carried out to identify the possible health consequences of the ingestion of heat-treated products, characterize the reaction kinetics leading to NFC and evaluate some mitigation procedures proposed by the CIAA toolbox, and finally develop a simple, rapid and non destructive control method based on fluorescence acquisition on the crushed food products and chemometric analysis of the spectral information. This paper summarizes the objectives and essential results obtained in the scope of the project, highlighting the need for evaluating the distribution of NFC in food products commercialized in Europe, as well as the impact of the food formula/recipe and process on Maillard derived NFC food levels. The potential of the Fluoralys sensor regarding its ability to control food contamination with NFC is presented. A decrease in NFC concentration of heat processed food should allow significantly limiting the exposure of populations to NFC and consequently the potential related health risk. (c) 2009 Elsevier Masson SAS. All rights reserved.

Priority and emerging pollutants in sewage sludge and fate during sludge treatment.

PubMed

Mailler, R; Gasperi, J; Chebbo, G; Rocher, V

2014-07-01

This paper aims at characterizing the quality of different treated sludges from Paris conurbation in terms of micropollutants and assessing their fate during different sludge treatment processes (STP). To achieve this, a large panel of priority and emerging pollutants (n=117) have been monitored in different STPs from Parisian wastewater treatment plants including anaerobic digestion, thermal drying, centrifugation and a sludge cake production unit. Considering the quality of treated sludges, comparable micropollutant patterns are found for the different sludges investigated (in mg/kg DM - dry matter). 35 compounds were detected in treated sludges. Some compounds (metals, organotins, alkylphenols, DEHP) are found in every kinds of sludge while pesticides or VOCs are never detected. Sludge cake is the most contaminated sludge, resulting from concentration phenomenon during different treatments. As regards treatments, both centrifugation and thermal drying have broadly no important impact on sludge contamination for metals and organic compounds, even if a slight removal seems to be possible with thermal drying for several compounds by abiotic transfers. Three different behaviors can be highlighted in anaerobic digestion: (i) no removal (metals), (ii) removal following dry matter (DM) elimination (organotins and NP) and iii) removal higher than DM (alkylphenols - except NP - BDE 209 and DEHP). Thus, this process allows a clear removal of biodegradable micropollutants which could be potentially significantly improved by increasing DM removal through operational parameters modifications (retention time, temperature, pre-treatment, etc.). Copyright © 2014 Elsevier Ltd. All rights reserved.

Effective treatment of PAH contaminated Superfund site soil with the peroxy-acid process.

PubMed

Scott Alderman, N; N'Guessan, Adeola L; Nyman, Marianne C

2007-07-31

Peroxy-organic acids are formed by the chemical reaction between organic acids and hydrogen peroxide. The peroxy-acid process was applied to two Superfund site soils provided by the U.S. Environmental Protection Agency (EPA). Initial small-scale experiments applied ratios of 3:5:7 (v/v/v) or 3:3:9 (v/v/v) hydrogen peroxide:acetic acid:deionized (DI) water solution to 5g of Superfund site soil. The experiment using 3:5:7 (v/v/v) ratio resulted in an almost complete degradation of the 14 EPA regulated polycyclic aromatic hydrocarbons (PAHs) in Bedford LT soil during a 24-h reaction period, while the 3:3:9 (v/v/v) ratio resulted in no applicable degradation in Bedford LT lot 10 soil over the same reaction period. Specific Superfund site soil characteristics (e.g., pH, total organic carbon content and particle size distribution) were found to play an important role in the availability of the PAHs and the efficiency of the transformation during the peroxy-acid process. A scaled-up experiment followed treating 150g of Bedford LT lot 10 soil with and without mixing. The scaled-up processes applied a 3:3:9 (v/v/v) solution resulting in significant decrease in PAH contamination. These findings demonstrate the peroxy-acid process as a viable option for the treatment of PAH contaminated soils. Further work is necessary in order to elucidate the mechanisms of this process.

Biochar modulates heavy metal toxicity and improves microbial carbon use efficiency in soil.

PubMed

Xu, Yilu; Seshadri, Balaji; Sarkar, Binoy; Wang, Hailong; Rumpel, Cornelia; Sparks, Donald; Farrell, Mark; Hall, Tony; Yang, Xiaodong; Bolan, Nanthi

2018-04-15

Soil organic carbon is essential to improve soil fertility and ecosystem functioning. Soil microorganisms contribute significantly to the carbon transformation and immobilisation processes. However, microorganisms are sensitive to environmental stresses such as heavy metals. Applying amendments, such as biochar, to contaminated soils can alleviate the metal toxicity and add carbon inputs. In this study, Cd and Pb spiked soils treated with macadamia nutshell biochar (5% w/w) were monitored during a 49days incubation period. Microbial phospholipid fatty acids (PLFAs) were extracted and analysed as biomarkers in order to identify the microbial community composition. Soil properties, metal bioavailability, microbial respiration, and microbial biomass carbon were measured after the incubation period. Microbial carbon use efficiency (CUE) was calculated from the ratio of carbon incorporated into microbial biomass to the carbon mineralised. Total PLFA concentration decreased to a greater extent in metal contaminated soils than uncontaminated soils. Microbial CUE also decreased due to metal toxicity. However, biochar addition alleviated the metal toxicity, and increased total PLFA concentration. Both microbial respiration and biomass carbon increased due to biochar application, and CUE was significantly (p<0.01) higher in biochar treated soils than untreated soils. Heavy metals reduced the microbial carbon sequestration in contaminated soils by negatively influencing the CUE. The improvement of CUE through biochar addition in the contaminated soils could be attributed to the decrease in metal bioavailability, thereby mitigating the biotoxicity to soil microorganisms. Copyright © 2017 Elsevier B.V. All rights reserved.

Occurrence and fate of emerging contaminants in municipal wastewater treatment plants from different geographical regions-a review.

PubMed

Tran, Ngoc Han; Reinhard, Martin; Gin, Karina Yew-Hoong

2018-04-15

Emerging contaminants, such as antibiotics, pharmaceuticals, personal care products, hormones, and artificial sweeteners, are recognized as new classes of water contaminants due to their proven or potential adverse effects on aquatic ecosystems and human health. This review provides comprehensive data on the occurrence of 60 emerging contaminants (ECs) in influent, treated effluent, sludge, and biosolids in wastewater treatment plants (WWTPs). In particular, data on the occurrence of ECs in the influents and effluents of WWTPs are systematically summarized and categorized according to geographical regions (Asia, Europe, and North America). The occurrence patterns of ECs in raw influent and treated effluents of WWTPs between geographical regions were compared and evaluated. Concentrations of most ECs in raw influent in Asian region tend to be higher than those in European and North American countries. Many antibiotics were detected in the influents and effluents of WWTPs at concentrations close to or exceeding the predicted no-effect concentrations (PNECs) for resistance selection. The efficacy of EC removal by sorption and biodegradation during wastewater treatment processes are discussed in light of kinetics and parameters, such as sorption coefficients (K d ) and biodegradation constants (k biol ), and physicochemical properties (i.e. log K ow and pK a ). Commonly used sampling and monitoring strategies are critically reviewed. Analytical research needs are identified, and novel investigative approaches for future monitoring studies are proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fuel quality/processing study. Volume 4: On site processing studies

NASA Technical Reports Server (NTRS)

Jones, G. E., Jr.; Cutrone, M.; Doering, H.; Hickey, J.

1981-01-01

Fuel treated at the turbine and the turbine exhaust gas processed at the turbine site are studied. Fuel treatments protect the turbine from contaminants or impurities either in the upgrading fuel as produced or picked up by the fuel during normal transportation. Exhaust gas treatments provide for the reduction of NOx and SOx to environmentally acceptable levels. The impact of fuel quality upon turbine maintenance and deterioration is considered. On site costs include not only the fuel treatment costs as such, but also incremental costs incurred by the turbine operator if a turbine fuel of low quality is not acceptably upgraded.

RATE OF TCE DEGRADATION IN A PLANT MULCH PASSIVE REACTIVE BARRIER (BIOWALL)

EPA Science Inventory

A passive reactive barrier was installed at the OU-1 site at Altus Air Force Base, Oklahoma to treat TCE contamination in ground water from a landfill. Depth to ground water varies from 1.8 to 2.4 meters below land surface. To intercept and treat the plume of contaminated groun...

Removal of Inorganic, Microbial, and Particulate Contaminants from Secondary Treated Wastewater - Village Marine Tec. Expeditionary Unit Water Purifier, Generation 1 at Gallup, NM

EPA Science Inventory

The EUWP was developed to treat challenging water sources with variable turbidity, chemical contamination, and very high total dissolved solids (TDS) including seawater, during emergency situations when other water treatment facilities are incapacitated. The EUWP components are ...

Why Do People Stop Treating Contaminated Drinking Water with Solar Water Disinfection (SODIS)?

ERIC Educational Resources Information Center

Tamas, Andrea; Mosler, Hans-Joachim

2011-01-01

Solar Water Disinfection (SODIS) is a simple method designed to treat microbiologically contaminated drinking water at household level. This article characterizes relapse behavior in comparison with continued SODIS use after a 7-month nonpromotion period. In addition, different subtypes among relapsers and continuers were assumed to diverge mainly…

Measurements of Mercury Released from Solidified/Stabilized Waste Forms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mattus, C.H.

2001-04-19

This report covers work performed during FY 1999-2000 in support of treatment demonstrations conducted for the Mercury Working Group of the U.S. Department of Energy (DOE) Mixed Waste Focus Area. In order to comply with the requirements of the Resource Conservation and Recovery Act, as implemented by the U.S. Environmental Protection Agency (EPA), DOE must use one of these procedures for wastes containing mercury at levels above 260 ppm: a retorting/roasting treatment or an incineration treatment (if the wastes also contain organics). The recovered radioactively contaminated mercury must then be treated by an amalgamation process prior to disposal. The DOEmore » Mixed Waste Focus Area and Mercury Working Group are working with the EPA to determine if some alternative processes could treat these types of waste directly, thereby avoiding for DOE the costly recovery step. They sponsored a demonstration in which commercial vendors applied their technologies for the treatment of two contaminated waste soils from Brookhaven National Laboratory. Each soil was contaminated with {approx}4500 ppm mercury; however, one soil had as a major radioelement americium-241, while the other contained mostly europium-152. The project described in this report addressed the need for data on the mercury vapor released by the solidified/stabilized mixed low-level mercury wastes generated during these demonstrations as well as the comparison between the untreated and treated soils. A related work began in FY 1998, with the measurement of the mercury released by amalgamated mercury, and the results were reported in ORNL/TM-13728. Four treatments were performed on these soils. The baseline was obtained by thermal treatment performed by SepraDyne Corp., and three forms of solidification/stabilization were employed: one using sulfur polymer cement (Brookhaven National Laboratory), one using portland cement [Allied Technology Group (ATG)], and a third using proprietary additives (Nuclear Fuel Services).« less

Rapid disinfection of E-Coliform contaminated water using WO3 semiconductor catalyst by laser-induced photo-catalytic process.

PubMed

Gondal, Mohammed A; Khalil, Amjad

2008-04-01

Laser-induced photo-catalysis process using WO(3) semiconductor catalyst was applied for the study of disinfection effectiveness of E-coliform-contaminated water. For this purpose, wastewater polluted with E-coliform bacteria was exposed to 355 nm UV radiations generated by third harmonic of Nd: YAG laser in special glass cell with and without WO(3) catalyst. E-Coliform quantification was performed by direct plating method to obtain the efficiency of each disinfection treatment. The dependence of disinfection process on laser irradiation energy, amount of catalyst and duration of laser irradiation was also investigated. The disinfection with WO(3) was quite efficient inactivating E-coliforms. For inactivation of E-coliforms, less than 8 minutes' laser irradiation was required, so that, the treated water complies with the microbial standards for drinking water. This study opens the possibility of application of this simple method in rural areas of developing countries using solar radiation.

An overview of electrokinetic soil flushing and its effect on bioremediation of hydrocarbon contaminated soil.

PubMed

Ramadan, Bimastyaji Surya; Sari, Gina Lova; Rosmalina, Raden Tina; Effendi, Agus Jatnika; Hadrah

2018-07-15

Combination of electrokinetic soil flushing and bioremediation (EKSF-Bio) technology has attracted many researchers attention in the last few decades. Electrokinetic is used to increase biodegradation rate of microorganisms in soil pores. Therefore, it is necessary to use solubilizing agents such as surfactants that can improve biodegradation process. This paper describes the basic understanding and recent development associated with electrokinetic soil flushing, bioremediation, and its combination as innovative hybrid solution for treating hydrocarbon contaminated soil. Surfactant has been widely used in many studies and practical applications in remediation of hydrocarbon contaminant, but specific review about those combination technology cannot be found. Surfactants and other flushing/solubilizing agents have significant effects to increase hydrocarbon remediation efficiency. Thus, this paper is expected to provide clear information about fundamental interaction between electrokinetic, flushing agents and bioremediation, principal factors, and an inspiration for ongoing and future research benefit. Copyright © 2018 Elsevier Ltd. All rights reserved.

Adsorption and mineralization of REE-lanthanum onto bacterial cell surface.

PubMed

Cheng, Yangjian; Zhang, Li; Bian, Xiaojing; Zuo, Hongyang; Dong, Hailiang

2017-07-11

A large number of rare earth element mining and application resulted in a series of problems of soil and water pollution. Environmental remediation of these REE-contaminated sites has become a top priority. This paper explores the use of Bacillus licheniformis to adsorb lanthanum and subsequent mineralization process in contaminated water. The maximum adsorption capacity of lanthanum on bacteria was 113.98 mg/g (dry weight) biomass. X-ray diffraction (XRD) and transmission electron microscopy (TEM) data indicated that adsorbed lanthanum on bacterial cell surface occurred in an amorphous form at the initial stage. Scanning electron microscopy with X-ray energy-dispersive spectroscopy (SEM/EDS) results indicated that lanthanum adsorption was correlated with phosphate. The amorphous material was converted into scorpion-like monazite (LaPO 4 nanoparticles) in a month. The above results provide a method of using bacterial surface as adsorption and nucleation sites to treat REE-contaminated water.

Adsorption of natural organic matter and disinfection byproduct precursors from surface water onto TiO2 nanoparticles: pH effects, isotherm modelling and implications for using TiO2 for drinking water treatment.

PubMed

Gora, Stephanie L; Andrews, Susan A

2017-05-01

Titanium dioxide is a photocatalyst that can remove organic contaminants of interest to the drinking water treatment industry, including natural organic matter (NOM) and disinfection byproduct (DBP) precursors. The photocatalytic reaction occurs in two steps: adsorption of the contaminant followed by degradation of the adsorbed contaminant upon irradiation with UV light. The second part of this process can lead to the formation of reactive intermediates and negative impacts on treated water quality, such as increased DBP formation potential (DBPfp). Adsorption alone does not result in the formation of reactive intermediates and thus may prove to be a safe way to incorporate TiO 2 into drinking water treatment processes. The goal of this study was to expand on the current understanding of NOM adsorption on TiO 2 and examine it in a drinking water context by observing NOM adsorption from real water sources and evaluating the effects of the resulting reductions on the DBPfp of the treated water. Bottle point isotherm tests were conducted with raw water from two Canadian water treatment plants adjusted to pH 4, pH 6 and pH 8 and dosed with TiO 2 nanoparticles. The DOC results were a good fit to a modified Freundlich isotherm. DBP precursors and liquid chromatography with organic carbon detection NOM fractions associated with DBP formation were removed to some extent at all pHs, but most effectively at pH 4. Copyright © 2017 Elsevier Ltd. All rights reserved.

Occurrence and diversity of both bacterial and fungal communities in dental unit waterlines subjected to disinfectants.

PubMed

Costa, Damien; Mercier, Anne; Gravouil, Kevin; Lesobre, Jérôme; Verdon, Julien; Imbert, Christine

2016-10-01

Chemical disinfectants are widely advocated to reduce the microbial contamination in dental unit waterlines (DUWL). However, until now their efficacy has been poorly examined after long-term application. In this study, through quantitative PCR and high-throughput sequencing, both bacterial and fungal communities were profiled from 8- to 12-year-old DUWL treated with disinfectants commonly used by European dentists. Water was collected from the tap water supplying units to the output exposure point of the turbine handpiece following a stagnation period and dental care activity. Results showed that (i) the unit itself is the principal source of microbial contamination and (ii) water stagnation, DU maintenance practices and quality of water supplying DU appeared as parameters driving the water quality. Despite disinfecting treatment combined to flushing process, the microbial contamination remained relevant in the studied output water, in association with a high bacterial and fungal diversity. The occurrence of potentially pathogenic microorganisms in these treated DUWL demonstrated a potential infectious risk for both patients and dental staff. A disinfectant shock before a prolonged stagnation period could limit the microbial proliferation inside DUWL. Necessity to proceed to regular water quality control of DUWL was highlighted. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Bioswales reduce contaminants associated with toxicity in urban storm water.

PubMed

Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Siegler, Katie; Tjeerdema, Ronald

2016-12-01

Contamination and toxicity associated with urban storm water runoff are a growing concern because of the potential impacts on receiving systems. California water regulators are mandating implementation of green infrastructure as part of new urban development projects to treat storm water and increase infiltration. Parking lot bioswales are low impact development practices that promote filtering of runoff through plants and soil. Studies have demonstrated that bioswales reduce concentrations of suspended sediments, metals, and hydrocarbons. There have been no published studies evaluating how well these structures treat current-use pesticides, and studies have largely ignored whether bioswales reduce toxicity in surface water. Three storms were monitored at 3 commercial and residential sites, and reductions of contaminants and associated toxicity were quantified. Toxicity testing showed that the majority of untreated storm water samples were toxic to amphipods (Hyalella azteca) and midges (Chironomus dilutus), and toxicity was reduced by the bioswales. No samples were toxic to daphnids (Ceriodaphnia dubia) or fish (Pimephales promelas). Contaminants were significantly reduced by the bioswales, including suspended solids (81% reduction), metals (81% reduction), hydrocarbons (82% reduction), and pyrethroid pesticides (74% reduction). The single exception was the phenypyrazole pesticide fipronil, which showed inconsistent treatment. The results demonstrate these systems effectively treat contaminated storm water associated with surface water toxicity but suggest that modifications of their construction may be required to treat some contaminant classes. Environ Toxicol Chem 2016;35:3124-3134. © 2016 SETAC. © 2016 SETAC.

Nationwide reconnaissance of contaminants of emerging concern in source and treated drinking waters of the United States

USGS Publications Warehouse

Glassmeyer, Susan T.; Furlong, Edward T.; Kolpin, Dana W.; Batt, Angela L.; Benson, Robert; Boone, J. Scott; Conerly, Octavia D.; Donohue, Maura J.; King, Dawn N.; Kostich, Mitchell S.; Mash, Heath E.; Pfaller, Stacy; Schenck, Kathleen M.; Simmons, Jane Ellen; Varughese, Eunice A.; Vesper, Stephen J.; Villegas, Eric N.; Wilson, Vickie S.

2017-01-01

When chemical or microbial contaminants are assessed for potential effect or possible regulation in ambient and drinking waters, a critical first step is determining if the contaminants occur and if they are at concentrations that may cause human or ecological health concerns. To this end, source and treated drinking water samples from 29 drinking water treatment plants (DWTPs) were analyzed as part of a two-phase study to determine whether chemical and microbial constituents, many of which are considered contaminants of emerging concern, were detectable in the waters. Of the 84 chemicals monitored in the 9 Phase I DWTPs, 27 were detected at least once in the source water, and 21 were detected at least once in treated drinking water. In Phase II, which was a broader and more comprehensive assessment, 247 chemical and microbial analytes were measured in 25 DWTPs, with 148 detected at least once in the source water, and 121 detected at least once in the treated drinking water. The frequency of detection was often related to the analyte's contaminant class, as pharmaceuticals and anthropogenic waste indicators tended to be infrequently detected and more easily removed during treatment, while per and polyfluoroalkyl substances and inorganic constituents were both more frequently detected and, overall, more resistant to treatment. The data collected as part of this project will be used to help inform evaluation of unregulated contaminants in surface water, groundwater, and drinking water.

Mycotic and aflatoxin contamination in Myristica fragrans seeds (nutmeg) and Capsicum annum (chilli), packaged in Italy and commercialized worldwide.

PubMed

Pesavento, G; Ostuni, M; Calonico, C; Rossi, S; Capei, R; Lo Nostro, A

2016-01-01

Aflatoxins are secondary metabolites of moulds known to be carcinogenic for humans, and therefore should not be ingested in high doses. This study aimed to determine the level of mould and aflatoxin contamination in dehydrated chilli and nutmeg imported from India and Indonesia, respectively, packaged in Italy, and commercialized worldwide. We tested 63 samples of chilli (22 sanitized through heat treatment and 41 not heat-treated) and 52 samples of nutmeg (22 heat-treated and 30 not heat-treated) for aflatoxin, moulds and moisture content. Heat-treated samples were less contaminated than untreated samples. Spices in powder form (both chilli and nutmeg) were more contaminated than whole ones. In untreated spices, we observed a positive correlation between mould and moisture content. Of the powdered nutmeg and chilli samples, 72.5% and 50% tested positive for aflatoxin contamination, with a range of 0-17.2 μg kg(-1) and 0-10.3 μg kg(-1), respectively. The steam treatment of spices would be useful in reducing the initial amount of moulds. Although the risk from the consumption of spices contaminated with aflatoxins is minimal, owing to the small amount used in food, preventive screening of the whole food chain is very important, especially because the most frequently identified toxin was B1, which is the most dangerous of the four toxins (B1, B2, G1, G2).

Nationwide reconnaissance of contaminants of emerging concern in source and treated drinking waters of the United States.

PubMed

Glassmeyer, Susan T; Furlong, Edward T; Kolpin, Dana W; Batt, Angela L; Benson, Robert; Boone, J Scott; Conerly, Octavia; Donohue, Maura J; King, Dawn N; Kostich, Mitchell S; Mash, Heath E; Pfaller, Stacy L; Schenck, Kathleen M; Simmons, Jane Ellen; Varughese, Eunice A; Vesper, Stephen J; Villegas, Eric N; Wilson, Vickie S

2017-03-01

When chemical or microbial contaminants are assessed for potential effect or possible regulation in ambient and drinking waters, a critical first step is determining if the contaminants occur and if they are at concentrations that may cause human or ecological health concerns. To this end, source and treated drinking water samples from 29 drinking water treatment plants (DWTPs) were analyzed as part of a two-phase study to determine whether chemical and microbial constituents, many of which are considered contaminants of emerging concern, were detectable in the waters. Of the 84 chemicals monitored in the 9 Phase I DWTPs, 27 were detected at least once in the source water, and 21 were detected at least once in treated drinking water. In Phase II, which was a broader and more comprehensive assessment, 247 chemical and microbial analytes were measured in 25 DWTPs, with 148 detected at least once in the source water, and 121 detected at least once in the treated drinking water. The frequency of detection was often related to the analyte's contaminant class, as pharmaceuticals and anthropogenic waste indicators tended to be infrequently detected and more easily removed during treatment, while per and polyfluoroalkyl substances and inorganic constituents were both more frequently detected and, overall, more resistant to treatment. The data collected as part of this project will be used to help inform evaluation of unregulated contaminants in surface water, groundwater, and drinking water. Published by Elsevier B.V.

MANAGING MICROBIAL CONTAMINATION IN URBAN WATERSHEDS

EPA Science Inventory

This paper presents different approaches for controlling pathogen contamination in urban watersheds for contamination resulting from point and diffuse sources. Point sources of pathogens can be treated by a disinfection technology of known effectiveness, and a desired reduction ...

MANAGING MICROBIAL CONTAMINATION IN URBAN WATERSHEDS

EPA Science Inventory

This paper presents different approaches for controlling pathogen contamination in urban watersheds for contamination resulting from point and diffuses sources. Point sources of pathogens can be treated by a disinfection technology of known effectiveness, and a desired reduction ...

Monitoring for contaminants of emerging concern in drinking water using POCIS passive samplers.

PubMed

Metcalfe, Chris; Hoque, M Ehsanul; Sultana, Tamanna; Murray, Craig; Helm, Paul; Kleywegt, Sonya

2014-03-01

Contaminants of emerging concern (CEC) have been detected in drinking water world-wide. The source of most of these compounds is generally attributed to contamination from municipal wastewater. Traditional water sampling methods (grab or composite) often require the concentration of large amounts of water in order to detect trace levels of these contaminants. The Polar Organic Compounds Integrative Sampler (POCIS) is a passive sampling technology that has been developed to concentrate trace levels of CEC to provide time-weighted average concentrations for individual compounds in water. However, few studies to date have evaluated whether POCIS is suitable for monitoring contaminants in drinking water. In this study, the POCIS was evaluated as a monitoring tool for CEC in drinking water over a period of 2 and 4 weeks with comparisons to typical grab samples. Seven "indicator compounds" which included carbamazepine, trimethoprim, sulfamethoxazole, ibuprofen, gemfibrozil, estrone and sucralose, were monitored in five drinking water treatment plants (DWTPs) in Ontario. All indicator compounds were detected in raw water samples from the POCIS in comparison to six from grab samples. Similarly, four compounds were detected in grab samples of treated drinking water, whereas six were detected in the POCIS. Sucralose was the only compound that was detected consistently at all five plants. The POCIS technique provided integrative exposures of CECs in drinking water at lower detection limits, while episodic events were captured via traditional sampling methods. There was evidence that the accumulation of target compounds by POCIS is a dynamic process, with adsorption and desorption on the sorbent occurring in response to ambient levels of the target compounds in water. CECs in treated drinking water were present at low ng L(-1) concentrations, which are not considered to be a threat to human health.

Development of an atmospheric monitoring plan for space station

NASA Technical Reports Server (NTRS)

Casserly, Dennis M.

1989-01-01

An environmental health monitoring plan for Space Station will ensure crew health during prolonged habitation. The Space Station, Freedom, will operate for extended periods, 90+ days, without resupply. A regenerative, closed loop life support system will be utilized in order to minimize resupply logistics and costs. Overboard disposal of wastes and venting of gases to space will be minimal. All waste material will be treated and recycled. The concentrated wastes will be stabilized and stored for ground disposal. The expected useful life of the station (decades) and the diversity of materials brought aboard for experimental or manufacturing purposes, increases the likelihood of cabin contamination. Processes by which cabin contamination can occur include: biological waste production, material off-gassing, process leakage, accidental containment breach, and accumulation due to poor removal efficiencies of the purification units. An industrial hygiene approach was taken to rationalize monitoring needs and to identify the substances likely to be present, the amount, and their hazard.

Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff.

PubMed

Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Cahn, Michael

2017-05-15

Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may be treated with simple systems designed to promote sorption of contaminants to vegetation and soils and promote infiltration. Two example systems are described: a bioswale treatment system for urban stormwater treatment, and a vegetated drainage ditch for treating agriculture irrigation runoff. Both have similar attributes that reduce contaminant loading in runoff: vegetation that results in sorption of the contaminants to the soil and plant surfaces, and water infiltration. These systems may also include the integration of granulated activated carbon as a polishing step to remove residual contaminants. Implementation of these systems in agriculture and urban watersheds requires system monitoring to verify treatment efficacy. This includes chemical monitoring for specific contaminants responsible for toxicity. The current paper emphasizes monitoring of current use pesticides since these are responsible for surface water toxicity to aquatic invertebrates.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meier, J.R.; Chang, L.W.; Meckes, M.C.

Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The earthworm toxicity bioassays were the 14-d survival test and 21-d reproduction test, using Lumbricus terrestris and Eisenia fetida andrei. The plant bioassays included phytotoxicity tests for seed germination and root elongation in lettuce and oats, and a genotoxicity test (anaphase aberrations) in Allium cepa (common onion). Although the PCB content of the soil was reduced by 99% (below themore » remediation goal), toxicity to earthworm reproduction remained essentially unchanged following remediation. Furthermore, phytotoxicity and genotoxicity were higher for the remediated soil compared to the untreated soil. The toxicity remaining after treatment appeared to be due to residual solvent introduced during the remediation process, and/or to heavy metals or other inorganic contaminants not removed by the treatment. Mixture studies involving isopropanol and known toxicants indicated possible synergistic effects of the extraction solvent and soil contaminants. The toxicity in plants was essentially eliminated by a postremediation, water-rinsing step. These results demonstrate a need for including toxicity measurements in the evaluation of technologies used in hazardous waste site remediations, and illustrate the potential value of such measurements for making modifications to remediation processes.« less

Evaluation of several biological monitoring techniques for hazard assessment of potentially contaminated wastewater and groundwater. Volume 3. Old O-field groundwater. Final report, July 1990-December 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burton, D.T.; Turley, S.D.

1992-03-01

The toxicity of contaminated Old O-Field (Edgewood Area of Aberdeen Proving Ground) groundwater and the reduction and/or elimination of toxicity by various treatment processes were evaluated. The study was divided into a bench scale and pilot scale study. The bench scale studies consisted of 48-h definitive acute toxicity tests run with daphnid neonates (Daphnia magna) and juvenile fathead minnows (Pimephales promelas) exposed to untreated Old O-Field groundwater and groundwater treated by metals precipitation, UV oxidation (H 2O2 ), carbon adsorption, and carbon adsorption/biological sludge. The pilot scale studies consisted of several 96-h definitive acute toxicity tests run with two freshwatermore » and two saltwater invertebrates and fish and Ames mutagenicity assays. Acute toxicity tests were run on untreated Old O-Field groundwater and groundwater treated by metals precipitation, UV oxidation (H2O2), air stripping, and carbon adsorption during the pilot scale study. The freshwater invertebrate and fish used in the study were daphnid neonates and juvenile fathead minnows, respectively. The saltwater invertebrate and fish were juvenile mysids (Mysidopsis bahia) and juvenile sheepshead minnows (Cyprinodon variegatus). Ames tests were run on untreated groundwater, UV oxidation-treated groundwater, and carbon-treated groundwater.... Groundwater, Aquatic, Toxicity, Daphnia, Daphnia magna, Fathead minnow, Pimephales promelas, Mysid, Mysidopsis bahia, Sheepshead minnow, Cyprinodon variegatus.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fruchter, Jonathan S.

In Situ Treatment of Chromate Contaminated Groundwater Jonathan S. Fruchter Pacific Northwest National Laboratory Abstract of paper published in Environmental Science and Technology, 2002 Although not as common as solvent or fuel products contamination, chromate (chromium (VI)) contamination of groundwater is relatively widespread. Chromate has a variety of industrial uses, including chrome plating, steel making, and use as a corrosion inhibitor, wood preservative, well-drilling fluid additive, biocide, and as a pigment in paints and primers. EPA has estimated that as many as 1300 sites in the United States may have groundwater contaminated with chromate. The paper discusses a number ofmore » approaches to in situ treatment of chromate contamination in groundwater aquifers. The approaches include various types of chemical treatments, biological treatments and natural attenuation. The strengths and weaknesses of each method are discussed and compared. Field examples of two types of chemical treatment, in situ redox manipulation and chemically enhanced pump and treat are presented. It is concluded that in situ methods show promise, but can be difficult to implement due to site-specific conditions and limited long-term experience with these methods. As more performance and cost data are acquired for the demonstrations that are ongoing, and continuing research increases our understanding of subsurface processes, in situ treatment methods for chromium (VI) contamination in groundwater should gain wider acceptance.« less

Hydrocarbon Degradation and Lead Solubility in a Soil Polluted with Lead and Used Motor Oil Treated by Composting and Phytoremediation.

PubMed

Escobar-Alvarado, L F; Vaca-Mier, M; López, R; Rojas-Valencia, M N

2018-02-01

Used lubricant oils and metals can be common soil pollutants in abandoned sites. When soil is contaminated with various hazardous wastes, the efficiency of biological treatments could be affected. The purpose of this work was to investigate the effect of combining phytoremediation and composting on the efficiency of hydrocarbon degradation and lead solubility in a soil contaminated with 31,823 mg/kg of total petroleum hydrocarbon (TPH) from used motor oil and 8260 mg/kg of lead. Mexican cactus (Opuntia ficus indica) and yard trimmings were added in the composting process, and lucerne (Medicago sativa) was used in the phytoremediation process. After a 9 week composting process, only 13% of the initial TPH concentration was removed. The following 20 week phytoremediation process removed 48% of TPH. The highest TPH degradation percentage (66%), was observed in the experiment with phytoremediation only. This work demonstrates sustainable technologies, such as biological treatments, represent low-cost options for remediation; however, they are not frequently used because they require long periods of time for success.

Heavy metal-immobilizing organoclay facilitates polycyclic aromatic hydrocarbon biodegradation in mixed-contaminated soil.

PubMed

Biswas, Bhabananda; Sarkar, Binoy; Mandal, Asit; Naidu, Ravi

2015-11-15

Soils contaminated with a mixture of heavy metals and polycyclic aromatic hydrocarbons (PAHs) pose toxic metal stress to native PAH-degrading microorganisms. Adsorbents such as clay and modified clay minerals can bind the metal and reduce its toxicity to microorganisms. However, in a mixed-contaminated soil, an adsorption process more specific to the metals without affecting the bioavailability of PAHs is desired for effective degradation. Furthermore, the adsorbent should enhance the viability of PAH-degrading microorganisms. A metal-immobilizing organoclay (Arquad(®) 2HT-75-bentonite treated with palmitic acid) (MIOC) able to reduce metal (cadmium (Cd)) toxicity and enhance PAH (phenanthrene) biodegradation was developed and characterized in this study. The MIOC differed considerably from the parent clay in terms of its ability to reduce metal toxicity (MIOC>unmodified bentonite>Arquad-bentonite). The MIOC variably increased the microbial count (10-43%) as well as activities (respiration 3-44%; enzymatic activities up to 68%), and simultaneously maintained phenanthrene in bioavailable form in a Cd-phenanthrene mixed-contaminated soil over a 21-day incubation period. This study may lead to a new MIOC-assisted bioremediation technique for PAHs in mixed-contaminated soils. Copyright © 2015 Elsevier B.V. All rights reserved.

Field evaluation of a horizontal well recirculation system for groundwater treatment: Field demonstration at X-701B Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korte, N.; Muck, M.; Kearl, P.

1998-08-01

This report describes the field-scale demonstration performed as part of the project, In Situ Treatment of Mixed Contaminants in Groundwater. This project was a 3{1/2} year effort comprised of laboratory work performed at Oak Ridge National Laboratory and fieldwork performed at the US Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS). The overall goal of the project was to evaluate in situ treatment of groundwater using horizontal recirculation coupled with treatment modules. Specifically, horizontal recirculation was tested because of its application to thin, interbedded aquifer zones. Mixed contaminants were targeted because of their prominence at DOE sites and becausemore » they cannot be treated with conventional methods. The project involved several research elements, including treatment process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and full-scale testing at a contaminated site. This report presents the results of the work at the contaminated site, X-701B at PORTS. Groundwater contamination at X-701B consists of trichloroethene (TCE) (concentrations up to 1800 mg/L) and technetium-998 (Tc{sup 99}) (activities up to 926 pCi/L).« less

Pilot-scale electrokinetic movement of HCB and Zn in real contaminated sediments enhanced with hydroxypropyl-beta-cyclodextrin.

PubMed

Li, Taiping; Yuan, Songhu; Wan, Jinzhong; Lin, Li; Long, Huayun; Wu, Xiaofeng; Lu, Xiaohua

2009-08-01

This study deals with the efficiency of a pilot-scale electrokinetic (EK) treatment on real aged sediments contaminated with hexachlorobenzene (HCB) and Zn. A total of 0.5m(3) of sediments were treated under a constant voltage in a polyvinyl chloride reactor. The changes of sediment pH, electrical conductivity (EC), organic content (OC), the transport of contaminants in sediments and the consumption of electric energy were evaluated. After 100 d processing, sediment pH slightly increased compared with the initial values, particularly in the bottom layer close to cathodic section, while sediment EC in most sections significantly decreased. Sediment OC in all sections increased, which implied that hydroxypropyl-beta-cyclodextrin (HPCD) was successfully penetrated across sediments by electroosmosis. Significant movement of contaminants was observed across sediments with negligible removals. Both HCB and Zn generally moved from sections near anode and accumulated near cathode. Upon the completion of treatment, the electric energy consumption was calculated as 563 kWhm(-3). This pilot-scale EK test indicates that it is difficult to achieve great removal of hydrophobic organic compounds (HOCs), or HOCs and heavy metal mixed contaminants, by EK treatment in large scale with the use of HPCD.

EFFECT OF SOIL PB INACTIVATION TREATMENTS ON BIOAVAILABILITY OF JOPLIN, MO, SMELTER CONTAMINATED SOIL PB TO RATS

EPA Science Inventory

The effects of treating contaminated soils with various soil amendments on the bioavailability of lead were assessed in the weanling rat model. The effect of treatment was assessed by comparing the adsorption of Pb of animals fed soil samples treated with (0.5%, 1% P and 2.5% Fe ...

FIELD SCALE EVALUATION OF TREATMENT OF TCE IN A BIOWALL AT THE OU-1 SITE

EPA Science Inventory

A passive reactive barrier (Biowall) was installed at the OU-1 site at Altus Air Force Base, Oklahoma to treat TCE contamination in ground water from a landfill. Depth to ground water varies from 1.8 to 2.4 meters below land surface. To intercept and treat the plume of contamin...

Preliminary screening of alternative technologies to incineration for treatment of chemical-agent-contaminated soil, Rocky Mountain Arsenal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shem, L.M.; Rosenblatt, D.H.; Smits, M.P.

1995-12-01

In support of the U.S. Army`s efforts to determine the best technologies for remediation of soils, water, and structures contaminated with pesticides and chemical agents, Argonne National Laboratory has reviewed technologies for treating soils contaminated with mustard, lewisite, sarin, o-ethyl s-(2- (diisopropylamino)ethyl)methyl-phosphonothioate (VX), and their breakdown products. This report focuses on assessing alternatives to incineration for dealing with these contaminants. For each technology, a brief description is provided, its suitability and constraints on its use are identified, and its overall applicability for treating the agents of concern is summarized. Technologies that merit further investigation are identified.

Occurrence, distribution and contamination levels of heat-resistant moulds throughout the processing of pasteurized high-acid fruit products.

PubMed

Santos, Juliana Lane Paixão Dos; Samapundo, Simbarashe; Biyikli, Ayse; Van Impe, Jan; Akkermans, Simen; Höfte, Monica; Abatih, Emmanuel Nji; Sant'Ana, Anderson S; Devlieghere, Frank

2018-05-19

Heat-resistant moulds (HRMs) are well known for their ability to survive pasteurization and spoil high-acid food products, which is of great concern for processors of fruit-based products worldwide. Whilst the majority of the studies on HRMs over the last decades have addressed their inactivation, few data are currently available regarding their contamination levels in fruit and fruit-based products. Thus, this study aimed to quantify and identify heat-resistant fungal ascospores from samples collected throughout the processing of pasteurized high-acid fruit products. In addition, an assessment on the effect of processing on the contamination levels of HRMs in these products was carried out. A total of 332 samples from 111 batches were analyzed from three processing plants (=three processing lines): strawberry puree (n = 88, Belgium), concentrated orange juice (n = 90, Brazil) and apple puree (n = 154, the Netherlands). HRMs were detected in 96.4% (107/111) of the batches and 59.3% (197/332) of the analyzed samples. HRMs were present in 90.9% of the samples from the strawberry puree processing line (1-215 ascospores/100 g), 46.7% of the samples from the orange juice processing line (1-200 ascospores/100 g) and 48.7% of samples from the apple puree processing line (1-84 ascospores/100 g). Despite the high occurrence, the majority (76.8%, 255/332) of the samples were either not contaminated or presented low levels of HRMs (<10 ascospores/100 g). For both strawberry puree and concentrated orange juice, processing had no statistically significant effect on the levels of HRMs (p > 0.05). On the contrary, a significant reduction (p < 0.05) in HRMs levels was observed during the processing of apple puree. Twelve species were identified belonging to four genera - Byssochlamys, Aspergillus with Neosartorya-type ascospores, Talaromyces and Rasamsonia. N. fumigata (23.6%), N. fischeri (19.1%) and B. nivea (5.5%) were the predominant species in pasteurized products. The quantitative data (contamination levels of HRMs) were fitted to exponential distributions and will ultimately be included as input to spoilage risk assessment models which would allow better control of the spoilage of heat treated fruit products caused by heat-resistant moulds. Copyright © 2018 Elsevier B.V. All rights reserved.

Performance study and influence of radiation emission energy and soil contamination level on γ-radiation shielding of stabilised/solidified radionuclide-polluted soils.

PubMed

Falciglia, Pietro P; Puccio, Valentina; Romano, Stefano; Vagliasindi, Federico G A

2015-05-01

This work focuses on the stabilisation/solidification (S/S) of radionuclide-polluted soils at different (232)Th levels using Portland cement alone and with barite aggregates. The potential of S/S was assessed applying a full testing protocol and calculating γ-radiation shielding (γRS) index, that included the measurement of soil radioactivity before and after the S/S as a function of the emission energy and soil contamination level. The results indicate that setting processes are strongly dependent on the contaminant concentration, and for contamination level higher than 5%, setting time values longer than 72 h. The addition of barite aggregates to the cement gout leads to a slight improvement of the S/S performance in terms of durability and contaminant leaching but reduces the mechanical resistance of the treated soils samples. Barite addition also causes an increase in the γ-rays shielding properties of the S/S treatment up to about 20%. Gamma-ray measurements show that γRS strongly depends on the energy, and that the radioactivity with the contamination level was governed by a linear trend, while, γRS index does not depend on the radionuclide concentration. Results allow the calculated γRS values and those available from other experiments to be applied to hazard radioactive soil contaminations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bioremediation of lead contaminated soil with Rhodobacter sphaeroides.

PubMed

Li, Xiaomin; Peng, Weihua; Jia, Yingying; Lu, Lin; Fan, Wenhong

2016-08-01

Bioremediation with microorganisms is a promising technique for heavy metal contaminated soil. Rhodobacter sphaeroides was previously isolated from oil field injection water and used for bioremediation of lead (Pb) contaminated soil in the present study. Based on the investigation of the optimum culturing conditions and the tolerance to Pb, we employed the microorganism for the remediation of Pb contaminated soil simulated at different contamination levels. It was found that the optimum temperature, pH, and inoculum size for R. sphaeroides is 30-35 °C, 7, and 2 × 10(8) mL(-1), respectively. Rhodobacter sphaeroides did not remove the Pb from soil but did change its speciation. During the bioremediation process, more available fractions were transformed to less accessible and inert fractions; in particular, the exchangeable phase was dramatically decreased while the residual phase was substantially increased. A wheat seedling growing experiment showed that Pb phytoavailability was reduced in amended soils. Results inferred that the main mechanism by which R. sphaeroides treats Pb contaminated soil is the precipitation formation of inert compounds, including lead sulfate and lead sulfide. Although the Pb bioremediation efficiency on wheat was not very high (14.78% root and 24.01% in leaf), R. sphaeroides remains a promising alternative for Pb remediation in contaminated soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigation into the importance of the stomatal pathway in the exchange of PCBs between air and plants.

PubMed

Barber, Jonathan L; Kurt, Perihan B; Thomas, Gareth O; Kerstiens, Gerhard; Jones, Kevin C

2002-10-15

The transfer of persistent organic pollutants (POPs) from air to vegetation is an important air-surface exchange process that affects global cycling and can result in human and wildlife exposure via the terrestrial food chain. To improve understanding of this process, the role of stomata in uptake of gas-phase polychlorinated biphenyls (PCBs) was investigated using Hemerocallis x hybrida "Black Eyed Stella", a plant with a high stomatal density. Uptake of PCBs was monitored over a 72-h period in the presence and absence of light. Uptake rates were significantly greater in illuminated (stomata open) plants than unilluminated (stomata closed) plants for 18 of the 28 measured PCB congeners (p < 0.05). Depuration of PCBs was monitored in a subsequent experiment over a period of 3 weeks. Levels after 3 weeks of depuration time were still much higher than the concentration prior to contamination. Tri- and tetrachlorinated PCBs showed the greatest depuration, with less than 20% and 50% of accumulated PCBs respectively remaining, while approximately 70% of higher chlorinated PCB congeners remained in the plants at the end of the experiment. Treatments with/without light (to control stomatal opening during uptake) and with/without abscisic acid (ABA) application (to control stomatal opening during depuration) were compared. After contamination indoors for 3 days, there was a significantly higher concentration of PCBs (p < 0.05) in the light contaminated plants than the dark-contaminated plants for 13 of the 28 measured PCB congeners. The ABA treatment affected depuration of PCB-18 only. "Light/ABA-treated" plants had a significantly slower depuration rate for PCB-18 than "light/untreated", "dark/ABA-treated", and "dark/untreated" plants (p < 0.05). The results of the study indicate that there is a stomatal effect on the rate of exchange of PCBs between Hemerocallis leaves and air.

Microbe Detector

NASA Technical Reports Server (NTRS)

1985-01-01

Under NASA contracts, McDonnell Douglas developed a microbial load monitor to detect bacterial contamination. Vitek Systems, Inc., a subsidiary, was created to commercialize the product for analyzing body fluids. With the AutoMicrobic System, infections may be treated more quickly. The process involves injecting the fluid into identification cards and screening the reaction. Antibiotic treatments are also suggested. Time in hospital and human error is reduced. There are also possible industrial and environmental applications.

PROCESS OF PURIFYING URANIUM

DOEpatents

Seaborg, G.T.; Orlemann, E.F.; Jensen, L.H.

1958-12-23

A method of obtaining substantially pure uranium from a uranium composition contaminated with light element impurities such as sodium, magnesium, beryllium, and the like is described. An acidic aqueous solution containing tetravalent uranium is treated with a soluble molybdate to form insoluble uranous molybdate which is removed. This material after washing is dissolved in concentrated nitric acid to obtaln a uranyl nitrate solution from which highly purified uranium is obtained by extraction with ether.

Nanostructured Shape Memory Alloys: Adaptive Composite Materials and Components

DTIC Science & Technology

2007-12-01

placing the composites between two stainless steel sheets to minimize contamination. The process described was effective in breaking the nickel...pieced, the discs were heat-treated at 9000C for 1 hour and quenched in ice water. Each quarter piece was placed between two stainless steel sheets of 0.15... martensite interfaces. Additionally a surface preparation technique was developed to provide minimal surface deformation necessary for observation of

Elimination of Mycoplasma Contamination from Infected Human Hepatocyte C3A Cells by Intraperitoneal Injection in BALB/c Mice.

PubMed

Weng, Jun; Li, Yang; Cai, Lei; Li, Ting; Peng, Gongze; Fu, Chaoyi; Han, Xu; Li, Haiyan; Jiang, Zesheng; Zhang, Zhi; Du, Jiang; Peng, Qing; Gao, Yi

2017-01-01

Background/Aims: The use of antibiotics to eliminate Mycoplasma contamination has some serious limitations. Mycoplasma contamination can be eliminated by intraperitoneal injection of BALB/c mice with contaminated cells combined with screening monoclonal cells. However, in vivo passage in mice after injection with contaminated cells requires a long duration (20-54 days). Furthermore, it is important to monitor for cross-contamination of mouse and human cells, xenotropic murine leukemia virus-related virus (XMRV) infection, and altered cell function after the in vivo treatment. The present study aimed to validate a reliable and simplified method to eliminate mycoplasma contamination from human hepatocytes. BALB/c mice were injected with paraffin oil prior to injection with cells, in order to shorten duration of intraperitoneal passage. Cross-contamination of mouse and human cells, XMRV infection and cell function-related genes and proteins were also evaluated. Methods: PCR and DNA sequencing were used to confirm Mycoplasma hyorhinis ( M. hyorhinis ) contamination in human hepatocyte C3A cells. Five BALB/c mice were intraperitoneally injected with 0.5 ml paraffin oil 1 week before injection of the cells. The mice were then intraperitoneally injected with C3A hepatocytes (5.0 × 10 6 /ml) contaminated with M. hyorhinis (6.2 ± 2.2 × 10 8 CFU/ml). Ascites were collected for monoclonal cell screening on the 14th day after injection of contaminated cells. Elimination of mycoplasma from cells was determined by PCR and Transmission Electron Microscopy (TEM). Human-mouse cell and XMRV contamination were also detected by PCR. Quantitative reverse transcription PCR and western blotting were used to compare the expression of genes and proteins among treated cells, non-treated infected cells, and uninfected cells. Results: Fourteen days after injection with cells, 4 of the 5 mice had ascites. Hepatocyte colonies extracted from the ascites of four mice were all mycoplasma-free. There was no cell cross-contamination or XMRV infection in treated cell cultures. Elimination of Mycoplasma resulted in partial or complete recovery in the expression of ALB, TF, and CYP3A4 genes as well as proteins. Proliferation of the treated cells was not significantly affected by this management. Conclusion: The method of elimination of Mycoplasma contamination in this study was validated and reproducible. Success was achieved in four of five cases examined. Compared to the previous studies, the duration of intraperitoneal passage in this study was significantly shorter.

Mass balance of emerging contaminants in the water cycle of a highly urbanized and industrialized area of Italy.

PubMed

Castiglioni, Sara; Davoli, Enrico; Riva, Francesco; Palmiotto, Marinella; Camporini, Paolo; Manenti, Angela; Zuccato, Ettore

2017-12-22

The occurrence of several classes of emerging contaminants (ECs) was assessed in the River Lambro basin, one of the most urbanized and industrialized areas of Italy. The study aims were to identify the main sources of ECs, quantify their amounts circulating in the water cycle, and study their fate in the aquatic environment. More than 80 ECs were selected among pharmaceuticals (PHARM), personal care products (PCPs), disinfectants (DIS), illicit drugs (IDs), perfluorinated compounds (PERF), alkylphenols and bisphenol A (Alk-BPA), and anthropogenic markers (AM). Specific analytical methods were developed for quantitative analysis based on solid phase extraction and liquid chromatography tandem mass spectrometry. ECs were measured in rivers upstream and downstream of the main city (Milan), and in untreated and treated wastewater from Milan to assess the contribution to river contamination, and in superficial and deep groundwater in the city area to study the relationship between river and groundwater contamination. Samples were collected in a two-year monitoring campaign. Almost all ECs were ubiquitous in untreated wastewater, at concentrations up to the μg/L range, and the most abundant classes were PHARM and AM. Removals during different wastewater treatment processes were studied and the most stable substances were PHARM, PCPs and PERF. The mass loads increased for all the classes of ECs along the River Lambro basin. A mass balance was done in the river basin and allowed to identify the main sources of contamination, which were domestic, from treated or untreated wastewater, for PHARM, PCPs and IDs, mainly industrial for PERF, and both industrial and domestic for Alk-BPA. The study of AM helped to identify direct discharges of untreated wastewater. A substantial contribution of surface water to groundwater contamination was observed. This study improves the knowledge on occurrence, sources and fate of multiple classes of ECs in a highly urbanized area providing useful information to help the establishment of EU regulations for ECs. Copyright © 2017 Elsevier Ltd. All rights reserved.

ASSESSMENT OF STACHYBOTRYS REGROWTH ON CONTAMINATED WALLBOARD AFTER TREATMENT WITH COMMON SURFACE CLEANERS/DISINFECTANTS

EPA Science Inventory

The paper describes results of experiments assessing the efficacy of treating mold-contaminated gypsum wallboard with cleaners and/or disinfectants. Although the accepted recommendations for handling Stachybotrys chartarum contaminated gypsum wallboard are removal and replacement...

SUMMARY OF WATERBORNE ILLNESS TRANSMITTED THROUGH CONTAMINATED GROUNDWATER

EPA Science Inventory

The use of contaminated, untreated or inadequately treated groundwater was responsible for 51 percent of all waterborne outbreaks and 40 percent of all waterborne illness reported in the United States during the period 1971-82. Contaminated, untreated or inadequately disinfected ...

Catalytic destruction of groundwater contaminants in reactive extraction wells

DOEpatents

McNab, Jr., Walt W.; Reinhard, Martin

2002-01-01

A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

Arsenic Remediation Enhancement Through Chemical Additions to Pump and Treat Operations

NASA Astrophysics Data System (ADS)

Wovkulich, K.; Mailloux, B. J.; Stute, M.; Simpson, H. J.; Keimowitz, A. R.; Powell, A.; Lacko, A.; Chillrud, S. N.

2008-12-01

Arsenic is a contaminant found at more than 500 US Superfund sites. Since pump and treat technologies are widely used for remediation of contaminated groundwater, increasing the efficiency of contaminant removal at such sites should allow limited financial resources to clean up more sites. The Vineland Chemical Company Superfund site is extensively contaminated with arsenic after waste arsenic salts were stored and disposed of improperly for much of the company's 44 year manufacturing lifetime. Despite approximately eight years of pump and treat remediation, arsenic concentrations in the recovery wells can still be greater than 1000 ppb. The arsenic concentrations in the groundwater remain high because of slow desorption of arsenic from contaminated aquifer solids. Extrapolation of laboratory column experiments suggest that continuing the current groundwater remediation practice based on flushing ambient groundwater through the system may require on the order of hundreds of years to clean the site. However, chemical additions of phosphate or oxalic acid into the aquifer could decrease the remediation time scale substantially. Laboratory results from a soil column experiment using input of 10 mM oxalic acid suggest that site clean up of groundwater could be decreased to as little as four years. Pilot scale forced gradient field experiments will help establish whether chemical additions can be effective for increasing arsenic mobilization from aquifer solids and thus substantially decrease pump and treat clean up time.

New techniques to control salinity-wastewater reuse interactions in golf courses of the Mediterranean regions

NASA Astrophysics Data System (ADS)

Beltrao, J.; Costa, M.; Rosado, V.; Gamito, P.; Santos, R.; Khaydarova, V.

2003-04-01

Due to the lack water around the Mediterranean regions, potable water luxurious uses - as in golf courses - are increasingly contested. In order to solve this problem, non conventional water resources (effluent, gray, recycled, reclaimed, brackish), like treated wastewater, for irrigation gained increasing role in the planning and development of additional water supplies in golf courses. In most cases, the intense use of effluent for irrigation attracted public awareness in respect of contaminating pathogens and heavy metals. The contaminating effect of salinity in soil and underground water is very often neglected. The objective of this work is to present the conventional techniques to control salinity of treated wastewater and to present some results on new clean techniques to solve this problem, in the framework of the INCO-COPERNICUS project (no. IC-15CT98-0105) "Adaptation of Efficient Water Use Criteria in Marginal Regions of Europe and Middle Asia with Scarce Sources Subject to Environmental Control, Climate Change and Socio-Economic Development" and of the INCO-DC project (no. IC18-CT98-0266) "Control of Salination and Combating Desertification Effects in the Mediterranean Region. Phase II". Saline water is the most common irrigation water in arid climates. Moreover, for each region treated wastewater is always more saline than tap water, and therefore, when treated wastewater is reused in golf courses, more salinity problems occur. Conventional techniques to combat the salination process in golf courses can be characterized by four generations: 1) Problem of root zone salination by soil leaching - two options can occur - when there is an impermeable layer, salts will be concentrated above this layer; on the other hand, when there is no impermeable layer, aquifers contamination can be observed; 2) Use of subsurface trickle irrigation - economy of water, and therefore less additional salts; however the problem of groundwater contamination due to natural rain or artificial leaching remained; 3) Enhanced fertilization increases turfgrass tolerance to salinity, but the contamination will be increased by other hazardous chemicals such as nitrate; 4) Use of salt tolerant turfgrass species this technique will be very useful to the plants, but does not solve the problem os soil or groundwater contamination. When reusing treated wastewater in the Mediterranean areas, the only way to control the salination process and to maintain the sustainability of golf courses is to combat the salination problems by environmentally safe and clean techniques. These new clean techniques include: 1) Use of salt removing turfgrass species; 2) Use of drought tolerant turfgrass species - reduction of salt application by deficit irrigation; 3) Reuse of minimal levels of wastewater enough to obtain a good visual appearance GVA of the turfgrass. Regarding these new clean techniques, experiments were carried out in golf courses of Algarve, Portugal, the most southwest part of Europe. It was shown: 1) Use of salt removing turfgrass species - 3 sprinkle irrigated cultivars were studied (Agrostis solonífera L.; Cynodon dactylon, L. and Penninsetum clandestinum Hochst ex Chiov). 2) Use of drought tolerant turfgrass species -responses to several levels of sprinkle irrigation wastewater and potable water (with and without fertilization). An experimental design, known as sprinkle point source was specially used to simulate the several levels of water application, expressed by the crop coefficient kc and by the crop evapotranspiration rate ETc. Turfgrass yield was enhanced linearly with the increased application of treated wastewater. 3) Reuse of minimal levels of wastewater enough to obtain a good visual appearance GVA of the turfgrass - The minimal crop coefficient kc for a good visual appearance GVA of the turfgrass was around 1.0 to potable water irrigated mixed cultivars (with 30 kg nitrogen ha-1 month-1) and 1.2 to wastewater irrigated Bermuda grass (without any mineral fertilization). As concluding remarks, our results show that these new clean techniques are a strong and powerful tool to control salinity and to avoid soil salination and to maintain sustainability of golf courses.

Methods for microbial filtration of fluids

DOEpatents

Carman, Margaret L.; Jackson, Kenneth J.; Knapp, Richard B.; Knezovich, John P.; Shah, Nilesh N.; Taylor, Robert T.

1996-01-01

Novel methods for purifying contaminated subsurface groundwater are disclosed. The method is involves contacting the contaminated subsurface groundwater with methanotrophic or heterotrophic microorganisms which produce contaminant-degrading enzymes. The microorganisms are derived from surface cultures and are injected into the ground so as to act as a biofilter. The contaminants which may be treated include organic or metallic materials and radionuclides.

Effect of manual feeding on the level of farmer's exposure to airborne contaminants in the confinement nursery pig house.

PubMed

Kim, Ki-Youn; Ko, Han-Jong; Kim, Hyeon-Tae; Kim, Chi-Nyon; Kim, Yoon-Shin; Roh, Young-Man

2008-04-01

The objective of the study is to demonstrate an effect of manual feeding on the level of farmer's exposure to airborne contaminants in the confinement nursery pig house. The levels of all the airborne contaminants besides respirable dust, total airborne fungi and ammonia were significantly higher in the treated nursery pig house with feeding than the control nursery pig house without feeding. Although there is no significant difference in respirable dust and total airborne fungi between the treatment and the control, their concentrations in the treated nursery pig house were also higher than the control nursery pig house. The result that the level of ammonia in the treated nursery pig house is lower than the control nursery pig house would be reasoned by the mechanism of ammonia generation in the pig house and adsorption property of ammonia to dust particles. In conclusion, manual feeding by farmer increased the exposure level of airborne contaminants compared to no feeding activity.

PERMEABLE REACTIVE BARRIER STRATEGIES FOR REMEDIATION OF ARSENIC-CONTAMINATED GROUNDWATER

EPA Science Inventory

Results are presented from laboratory batch tests using zero-valent iron to treat arsenic-contaminated groundwater. The laboratory tests were conducted using near- neutral pH groundwater from a contaminated aquifer located adjacent to a custom smelting facility. Experiments we...

THE IMPACT OF PARTIAL DNAPL SOURCE ZONE REMEDIATION

EPA Science Inventory

Dense non-aqueous phase liquids (DNAPL) constitute a long-term source of groundwater contamination and a significant effort is usually required to treat these contaminated waters and bring them back to maximum contaminant level (MCL) required by the regulatory authorities.
Fi...

An overview of the geological controls in underground coal gasification

NASA Astrophysics Data System (ADS)

Mohanty, Debadutta

2017-07-01

Coal’s reign will extend well into this millennium as the global demand for coal is expected to increase on average by 2-1% per year through 2019. Enhanced utilization of the domestic coal resource through clean coal technologies is necessary to meet the energy needs while achieving reduced emissions. Underground coal gasification (UCG) is one of such potential technologies. Geology of the area plays decisive role throughout the life of a UCG project and imperative for every phase of the project cycle starting from planning, site selection, design to cessation of operations and restoration of the site. Impermeable over/underlying strata with low porosity and less deformation are most suitable for UCG processes as they act as seal between the coal seam and the surrounding aquifers while limiting the degree of subsidence. Inrush of excess water into the gasification chamber reduces the efficacy of the process and may even quench the reactions in progress. Presence of fresh water aquifer in the vicinity of target coal seam should be abandoned in order to avoid groundwater contamination. UCG is not a proven technology that is still evolving and there are risks that need to be monitored and managed. Effective shutdown programme should intend at minimising the post-burn contaminant generation by flushing out potential organic and inorganic contaminants from the underground strata and treating contaminants, and to restore ground water quality to near baseline conditions.

Assessment of water-soluble thiourea-formaldehyde (WTF) resin for stabilization/solidification (S/S) of heavy metal contaminated soils.

PubMed

Liu, She-Jiang; Jiang, Jia-Yu; Wang, Shen; Guo, Yu-Peng; Ding, Hui

2018-03-15

Stabilization/Solidification (S/S) can be regarded as necessary for remediation of heavy metal contaminated soil. There is, however, solid agent is not very convenient to use. Water-soluble thiourea-formaldehyde (WTF) is a novel chelating agent, which has more practical applications. The process of WTF resin for S/S process of heavy metal contaminated soils was studied. Laboratory-prepared slurries, made of field soils spiked with Cd 2+ and Cr 6+ were treated with WTF resin. The toxicity characteristic leaching procedure (TCLP) showed that with 2 wt% WTF, in the neutral condition of soil after treatment for 7 d, the leaching concentrations of Cd 2+ and Cr 6+ in contaminated soil were decreased by 80.3% and 92.6% respectively. Moreover, Tessier sequence extraction procedure showed WTF resin reduced the leaching concentration by transforming heavy metal from exchange form to organic form. The structure of WTF is obtained according to elemental analysis result and reaction mechanism. Through analysis of the infrared spectrogram of WTF and WTF heavy mental chelating precipitation, WTF can form stable chelate with heavy mental through coordination. The significant groups are hydroxyl, nitrogen and sulphur function groups in WTF mainly. Toxicology test revealed that the WTF resin is nontoxic to microorganism in the soils. Copyright © 2017 Elsevier B.V. All rights reserved.

Adsorption performance and mechanism of magnetic reduced graphene oxide in glyphosate contaminated water.

PubMed

Li, Yajuan; Zhao, Chuanqi; Wen, Yujuan; Wang, Yuanyuan; Yang, Yuesuo

2018-05-16

In this study, the magnetic reduced graphene oxide (RGO/Fe 3 O 4 ), with easy separation and high adsorption performance, was prepared and used to treat glyphosate (GLY) contaminated water. GLY adsorption performance of RGO/Fe 3 O 4 was investigated, and influences of pH, adsorption time, temperature, contaminant concentration, and competing anions were analyzed. Moreover, the adsorption mechanism was discussed in the light of several characterization methods, including scanning electron microscopy (SEM), energy dispersive spectrum (EDS), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The results demonstrated that the RGO/Fe 3 O 4 presented a significant GLY adsorption capacity and acid condition was beneficial for this adsorption. The pseudo-second-order kinetic model and the Langmuir model correlated satisfactorily to the experimental data, indicating that this process was controlled by chemical adsorption and monolayer adsorption. Thermodynamic studies revealed that the adsorption of glyphosate onto RGO/Fe 3 O 4 was spontaneous, endothermic, and feasible process. High temperatures were beneficial to GLY adsorption. The GLY adsorption mechanism of RGO/Fe 3 O 4 was mainly attributed to hydrogen-bond interaction, electrostatic interaction, and coordination. Therefore, the RGO/Fe 3 O 4 investigated in this research may offer an attractive adsorbent candidate for treatment of glyphosate contaminated water and warrant further study as a mechanism for glyphosate efficient removal.

Assessing the hydrocarbon degrading potential of indigenous bacteria isolated from crude oil tank bottom sludge and hydrocarbon-contaminated soil of Azzawiya oil refinery, Libya.

PubMed

Mansur, Abdulatif A; Adetutu, Eric M; Kadali, Krishna K; Morrison, Paul D; Nurulita, Yuana; Ball, Andrew S

2014-09-01

The disposal of hazardous crude oil tank bottom sludge (COTBS) represents a significant waste management burden for South Mediterranean countries. Currently, the application of biological systems (bioremediation) for the treatment of COTBS is not widely practiced in these countries. Therefore, this study aims to develop the potential for bioremediation in this region through assessment of the abilities of indigenous hydrocarbonoclastic microorganisms from Libyan Hamada COTBS for the biotreatment of Libyan COTBS-contaminated environments. Bacteria were isolated from COTBS, COTBS-contaminated soil, treated COTBS-contaminated soil, and uncontaminated soil using Bushnell Hass medium amended with Hamada crude oil (1 %) as the main carbon source. Overall, 49 bacterial phenotypes were detected, and their individual abilities to degrade Hamada crude and selected COBTS fractions (naphthalene, phenanthrene, eicosane, octadecane and hexane) were evaluated using MT2 Biolog plates. Analyses using average well colour development showed that ~90 % of bacterial isolates were capable of utilizing representative aromatic fractions compared to 51 % utilization of representative aliphatics. Interestingly, more hydrocarbonoclastic isolates were obtained from treated contaminated soils (42.9 %) than from COTBS (26.5 %) or COTBS-contaminated (30.6 %) and control (0 %) soils. Hierarchical cluster analysis (HCA) separated the isolates into two clusters with microorganisms in cluster 2 being 1.7- to 5-fold better at hydrocarbon degradation than those in cluster 1. Cluster 2 isolates belonged to the putative hydrocarbon-degrading genera; Pseudomonas, Bacillus, Arthrobacter and Brevundimonas with 57 % of these isolates being obtained from treated COTBS-contaminated soil. Overall, this study demonstrates that the potential for PAH degradation exists for the bioremediation of Hamada COTBS-contaminated environments in Libya. This represents the first report on the isolation of hydrocarbonoclastic bacteria from Libyan COTBS and COTBS-contaminated soil.

UV irradiation and autoclave treatment for elimination of contaminating DNA from laboratory consumables.

PubMed

Gefrides, Lisa A; Powell, Mark C; Donley, Michael A; Kahn, Roger

2010-02-01

Laboratories employ various approaches to ensure that their consumables are free of DNA contamination. They may purchase pre-treated consumables, perform quality control checks prior to casework, and use in-house profile databases for contamination detection. It is better to prevent contamination prior to DNA typing than identify it after samples are processed. To this end, laboratories may UV irradiate or autoclave consumables prior to use but treatment procedures are typically based on killing microorganisms and not on the elimination of DNA. We report a systematic study of UV and autoclave treatments on the persistence of DNA from saliva. This study was undertaken to determine the best decontamination strategy for the removal of DNA from laboratory consumables. We have identified autoclave and UV irradiation procedures that can eliminate nanogram quantities of contaminating DNA contained within cellular material. Autoclaving is more effective than UV irradiation because it can eliminate short fragments of contaminating DNA more effectively. Lengthy autoclave or UV irradiation treatments are required. Depending on bulb power, a UV crosslinker may take a minimum of 2h to achieve an effective dose for elimination of nanogram quantities of contaminating DNA (>7250mJ/cm(2)). Similarly autoclaving may also take 2h to eliminate similar quantities of contaminating DNA. For this study, we used dried saliva stains to determine the effective dose. Dried saliva stains were chosen because purified DNA as well as fresh saliva are less difficult to eradicate than dried stains and also because consumable contamination is more likely to be in the form of a collection of dry cells.

Iron-based catalysts for photocatalytic ozonation of some emerging pollutants of wastewater.

PubMed

Espejo, Azahara; Beltrán, Fernando J; Rivas, Francisco J; García-Araya, Juan F; Gimeno, Olga

2015-01-01

A synthetic secondary effluent containing an aqueous mixture of emerging contaminants (ECs) has been treated by photocatalytic ozonation using Fe(3+) or Fe3O4 as catalysts and black light lamps as the radiation source. For comparative purposes, ECs have also been treated by ultraviolet radiation (UVA radiation, black light) and ozonation (pH 3 and 7). With the exception of UVA radiation, O3-based processes lead to the total removal of ECs in the mixture. The time taken to achieve complete degradation depends on the oxidation process applied. Ozonation at pH 3 is the most effective technique. The addition of iron based catalysts results in a slight inhibition of the parent compounds degradation rate. However, a positive effect is experienced when measuring the total organic carbon (TOC) and the chemical oxygen demand (COD) removals. Photocatalytic oxidation in the presence of Fe(3+) leads to 81% and 88% of TOC and COD elimination, respectively, compared to only 23% and 29% of TOC and COD removals achieved by single ozonation. The RCT concept has been used to predict the theoretical ECs profiles in the homogeneous photocatalytic oxidation process studied. Treated wastewater effluent was toxic to Daphnia magna when Fe(3+) was used in photocatalytic ozonation. In this case, toxicity was likely due to the ferryoxalate formed in the process. Single ozonation significantly reduced the toxicity of the treated wastewater.

Photocatalytic Degradation Effect of μ-Dielectric Barrier Discharge Plasma Treated Titanium Dioxide Nanoparticles on Environmental Contaminant.

PubMed

Seo, Hyeon Jin; Hwang, Ki-Hwan; Na, Young Hoon; Boo, Jin-Hyo

2018-09-01

This study focused on the photocatalytic degradation effect of the μ-dielectric barrier discharge (μ-DBD) plasma treated titanium dioxide (TiO2) nanoparticles on environmental contaminant such as formaldehyde. TiO2 nanoparticles were treated by a μ-DBD plasma source with nitrogen gas. We analyzed the degradation of formaldehyde with the plasma treated TiO2 nanoparticles by UV-visible spectrophotometer (UV-VIS), and demonstrated that the photocatalytic activity of the μ-DBD plasma-treated TiO2 nanoparticles showed significantly high catalytic efficiency rather than without plasma treated TiO2 nanoparticles. Field emission scanning electron microscopes (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and water contact angle analyzer were used to measure the effects of photocatalytic degradation for the plasma treated TiO2 nanoparticles.

ENGINEERING ISSUE: TECHNOLOGY ALTERNATIVES FOR THE REMEDIATION OF PCB-CONTAMINATED SOIL AND SEDIMENT

EPA Science Inventory

Because of the increased need for Superfund decision-makers to have a working knowledge of the remedial capabilities available to treat soil and sediment contaminated with polychlorinated biphenyls (PCBs), the Superfund Engineering Forum has identified remediation of PCB-contamin...

EVALUATION OF BIOAEROSOL COMPONENTS, GENERATION FACTORS, AND AIRBORNE TRANSPORT ASSOCIATED WITH LIME TREATMENT OF CONTAMINATED SEDIMENT

EPA Science Inventory

Lime treatment has been used in contaminated sediment management activities for many purposes such as dewatering, improvement of physical properties, and reducing contaminant mobility. Exothermic volatilization of volatile organic compounds from lime-treated sediment is well kno...

Using Phytoremediation to Clean Up Contamination at Military Installations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zellmer, S.D.; Hinchman, R.R.; Negri, M.C.

1997-07-01

During and following World War II, wastes from the production of munitions and other military materials were disposed of using the best available practices acceptable at that time. However, these disposal methods often contaminated soil and groundwater with organic compounds and metals that require cleanup under current regulations. An emerging technology for cleaning contaminated soils and shallow groundwater is phytoremediation, an environmentally friendly, low- cost, and low-tech process. Phytoremediation encompasses all plant- influenced biological, chemical, and physical processes that aid in the uptake, degradation, and metabolism of contaminants by either plants or free-living organisms in the plant`s rhizosphere. A phytoremediationmore » system can be viewed as a biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the soil and below-ground ecosystem for subsequent productive use. Argonne National Laboratory (ANL) has been conducting basic and applied research in phytoremediation since 1990. Initial greenhouse studies evaluated salt-tolerant wetland plants to clean UP and reduce the volume of salty `produced water` from petroleum wells. Results of these studies were used to design a bioreactor for processing produced water that is being demonstrated at a natural gas well in Oklahoma; this system can reduce produced water volume by about 75% in less than eight days, representing substantial savings in waste disposal cost. During 1994, ANL conducted a TNT plant uptake and in situ remediation study in a ridge-and-furrow area used for the disposal of pink water at the Joliet Army Ammunition Plant.« less

The spectroscopic detection of exogenous material in fingerprints after development with powders and recovery with adhesive lifters.

PubMed

West, Matthew J; Went, Michael J

2008-01-15

The application of powders to fingerprints has long been established as an effective and reliable method for developing latent fingerprints. The powders adhere to the ridge pattern of the fingerprint only, thus allowing the image to be visualised. Fingerprints developed in situ at a crime scene routinely undergo lifting with specialist tapes to facilitate subsequent laboratory analysis. As with all recovered evidence these samples would be stored in evidence bags to allow secure transit from the scene to the laboratory and also to preserve the chain of evidence. In this paper, the application of Raman spectroscopy for the analysis of exogenous material in latent fingerprints is reported for contaminated fingerprints that had been treated with powders and also subsequently lifted with adhesive tapes. A selection of over the counter (OTC) analgesics were used as samples for the analysis and contaminated fingerprints were deposited on clean glass slides. The application of aluminium or iron based powders to contaminated fingerprints did not interfere with the Raman spectra obtained for the contaminants. In most cases background fluorescence attributed to the sebaceous content of the latent fingerprint was reduced by the application of the powder thus reducing spectral interference. Contaminated fingerprints developed with powders and then lifted with lifting tapes were also examined. The combination of these two techniques did not interfere with the successful analysis of exogenous contaminants by Raman spectroscopy. The lifting process was repeated using hinge lifters. As the hinge lifters exhibited strong Raman bands the spectroscopic analysis was more complex and an increase in the number of exposures to the detector allowed for improved clarification. Raman spectra of developed and lifted fingerprints recorded through evidence bags were obtained and it was found that the detection process was not compromised in any way. Although the application of powders did not interfere with the detection process the time taken to locate the contaminant was increased due to the physical presence of more material within the fingerprint. The presence of interfering Raman bands from lifting tapes is another potential complication. This, however, could be removed by spectral subtraction or by the choice of lifting tapes that have only weak Raman bands.

Combination of microbial oxidation and biogenic schwertmannite immobilization: A potential remediation for highly arsenic-contaminated soil.

PubMed

Yang, Zhihui; Wu, Zijian; Liao, Yingping; Liao, Qi; Yang, Weichun; Chai, Liyuan

2017-08-01

Here, a novel strategy that combines microbial oxidation by As(III)-oxidizing bacterium and biogenic schwertmannite (Bio-SCH) immobilization was first proposed and applied for treating the highly arsenic-contaminated soil. Brevibacterium sp. YZ-1 isolated from a highly As-contaminated soil was used to oxidize As(III) in contaminated soils. Under optimum culture condition for microbial oxidation, 92.3% of water-soluble As(III) and 84.4% of NaHCO 3 -extractable As(III) in soils were removed. Bio-SCH synthesized through the oxidation of ferrous sulfate by Acidithiobacillus ferrooxidans immobilize As(V) in the contaminated soil effectively. Consequently, the combination of microbial oxidation and Bio-SCH immobilization performed better in treating the highly As-contaminated soil with immobilization efficiencies of 99.3% and 82.6% for water-soluble and NaHCO 3 -extractable total As, respectively. Thus, the combination can be considered as a green remediation strategy for developing a novel and valuable solution for As-contaminated soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of the Aerobic Oxidation of cis-Dichloroethene and Vinyl Chloride in Support of Bioremediation of Chloroethene-Contaminated Sites

DTIC Science & Technology

2004-11-05

perchloroethylene) PCR polymerase chain reaction SERDP Strategic Environmental Research and Development Program TCE trichloroethene VC vinyl chloride iv...from one of the enrichments, which was inoculated with activated carbon from a pump-and-treat plant (Dortmund, Germany) processing chloroethene...dependent enzyme activity in extracts from VC and ethene-grown cells 8 (Coleman and Spain, 2003a). PCR amplifications using primers targeted at

Factors affecting sodium hypochlorite extraction of CCA from treated wood.

PubMed

Gezer, E D; Cooper, P A

2009-12-01

Significant amounts of chromated copper arsenate (CCA) treated wood products, such as utility poles and residential construction wood, remain in service. There is increasing public concern about environmental contamination from CCA-treated wood when it is removed from service for reuse or recycling, placed in landfills or burned in commercial incinerators. In this paper, we investigated the effects of time, temperature and sodium hypochlorite concentration on chromium oxidation and extraction of chromated copper arsenate from CCA-treated wood (Type C) removed from service. Of the conditions evaluated, reaction of milled wood with sodium hypochlorite for one hour at room temperature followed by heating at 75 degrees C for two hours gave the highest extraction efficiency. An average of 95% Cr, 99% Cu and 96% As could be removed from CCA-treated, milled wood by this process. Most of the extracted chromium was oxidized to the hexavalent state and could therefore be recycled in a CCA treating solution. Sodium hypochlorite extracting solutions could be reused several times to extract CCA components from additional treated wood samples.

Methods for removing contaminants from algal oil

DOEpatents

Lupton, Francis Stephen

2016-09-27

Methods for removing contaminants from algal oil are provided. In an embodiment, a method comprises the steps of combining a sulfuric acid-aqueous solution that has a pH of about 1 or less with a contaminant-containing algal oil at treatment conditions effective to form an effluent. The effluent comprises a treated algal oil phase and contaminants in an acidic aqueous phase. The contaminants comprise metals, phosphorus, or combinations thereof. The acidic aqueous phase is removed from the effluent to form a contaminant-depleted algal oil.

Modular Advanced Oxidation Process Enabled by Cathodic Hydrogen Peroxide Production

PubMed Central

2015-01-01

Hydrogen peroxide (H2O2) is frequently used in combination with ultraviolet (UV) light to treat trace organic contaminants in advanced oxidation processes (AOPs). In small-scale applications, such as wellhead and point-of-entry water treatment systems, the need to maintain a stock solution of concentrated H2O2 increases the operational cost and complicates the operation of AOPs. To avoid the need for replenishing a stock solution of H2O2, a gas diffusion electrode was used to generate low concentrations of H2O2 directly in the water prior to its exposure to UV light. Following the AOP, the solution was passed through an anodic chamber to lower the solution pH and remove the residual H2O2. The effectiveness of the technology was evaluated using a suite of trace contaminants that spanned a range of reactivity with UV light and hydroxyl radical (HO•) in three different types of source waters (i.e., simulated groundwater, simulated surface water, and municipal wastewater effluent) as well as a sodium chloride solution. Irrespective of the source water, the system produced enough H2O2 to treat up to 120 L water d–1. The extent of transformation of trace organic contaminants was affected by the current density and the concentrations of HO• scavengers in the source water. The electrical energy per order (EEO) ranged from 1 to 3 kWh m–3, with the UV lamp accounting for most of the energy consumption. The gas diffusion electrode exhibited high efficiency for H2O2 production over extended periods and did not show a diminution in performance in any of the matrices. PMID:26039560

Application of a Re-Pd bimetallic catalyst for treatment of perchlorate in waste ion-exchange regenerant brine.

PubMed

Liu, Jinyong; Choe, Jong Kwon; Sasnow, Zachary; Werth, Charles J; Strathmann, Timothy J

2013-01-01

Concentrated sodium chloride (NaCl) brines are often used to regenerate ion-exchange (IX) resins applied to treat drinking water sources contaminated with perchlorate (ClO(4)(-)), generating large volumes of contaminated waste brine. Chemical and biological processes for ClO(4)(-) reduction are often inhibited severely by high salt levels, making it difficult to recycle waste brines. Recent work demonstrated that novel rhenium-palladium bimetallic catalysts on activated carbon support (Re-Pd/C) can efficiently reduce ClO(4)(-) to chloride (Cl(-)) under acidic conditions, and here the applicability of the process for treating waste IX brines was examined. Experiments conducted in synthetic NaCl-only brine (6-12 wt%) showed higher Re-Pd/C catalyst activity than in comparable freshwater solutions, but the rate constant for ClO(4)(-) reduction measured in a real IX waste brine was found to be 65 times lower than in the synthetic NaCl brine. Through a series of experiments, co-contamination of the IX waste brine by excess NO(3)(-) (which the catalyst reduces principally to NH(4)(+)) was found to be the primary cause for deactivation of the Re-Pd/C catalyst, most likely by altering the immobilized Re component. Pre-treatment of NO(3)(-) using a different bimetallic catalyst (In-Pd/Al(2)O(3)) improved selectivity for N(2) over NH(4)(+) and enabled facile ClO(4)(-) reduction by the Re-Pd/C catalyst. Thus, sequential catalytic treatment may be a promising strategy for enabling reuse of waste IX brine containing NO(3)(-) and ClO(4)(-). Copyright © 2012 Elsevier Ltd. All rights reserved.

Nutrient-enhanced n-alkanes biodegradation and succession of bacterial communities

NASA Astrophysics Data System (ADS)

Sun, Yanyu; Wang, Hui; Li, Junde; Wang, Bin; Qi, Cancan; Hu, Xiaoke

2017-11-01

Bioremediation, is an effective and environment-friendly method of cleaning up crude oil pollution after an oil spill. However, the in situ bioremediation of crude oil is usually inhibited by deficiency of inorganic nutrients. To understand the effects of nutrient addition on the bioremediation of crude oil and the succession of bacterial communities during process of bioremediation, microcosms containing oil-contaminated sediments were constructed and biodegradation of crude oil was assessed based on the depletion of different ingredients. We used two culture-independent methods, denaturing gradient gel electrophoresis and a 16S rRNA gene based clone library, to analyze the succession of bacterial communities. The results suggested n-alkanes were degraded after 30 days and that nutrient amendments significantly improved the efficiency of their biodegradation. Moreover, oil contamination and nutrient amendments could dramatically change bacterial community structures. Lower diversity was detected after being contaminated with oil. For instance, bacterial clones affiliated with the phylum Armatimonadetes, Firmicutes, Gemmatimonadetes, and Planctomycetes and the class Deltaproteobacteria and Epsilonproteobacteria could not be identified after 30 days of incubation with crude oil. However, "professional hydrocarbonocastic bacteria" became abundant in samples treated with oil during the bioremediation period, while these clones were almost completely absent from the control plots. Interestingly, bioinformatics analysis showed that even when dramatic differences in oil biodegradation efficiency were observed, bacterial communities in the plots with nutrient amendments were not significantly different from those in plots treated with oil alone. These findings indicated that nutrient amendments could stimulate the process of biodegradation but had less impact on bacterial communities. Overall, nutrient amendments might be able to stimulate the growth of n-alkane degrading bacteria.

Heating of solid earthen material, measuring moisture and resistivity

DOEpatents

Heath, William O.; Gauglitz, Phillip A.; Pillay, Gautam; Bergsman, Theresa M.; Eschbach, Eugene A.; Goheen, Steven C.; Richardson, Richard L.; Roberts, Janet S.; Schalla, Ronald

1996-01-01

The present invention includes a method of treating solid earthen material having volatile, semi-volatile, and non-volatile contaminants that utilizes electrical energy. A plurality of electrodes are inserted into a region of earthen material to be treated in a selected geometric pattern. Varying phase and voltages configurations are applied to corresponding electrodes to achieve heating, physical phase changes, and the placement of substances within the treatment region. Additionally, treatment mediums can be added to either treat the contamination within the soil or to restrict their mobility.

Heating of solid earthen material, measuring moisture and resistivity

DOEpatents

Heath, W.O.; Gauglitz, P.A.; Pillay, G.; Bergsman, T.M.; Eschbach, E.A.; Goheen, S.C.; Richardson, R.L.; Roberts, J.S.; Schalla, R.

1996-08-13

The present invention includes a method of treating solid earthen material having volatile, semi-volatile, and non-volatile contaminants that utilizes electrical energy. A plurality of electrodes are inserted into a region of earthen material to be treated in a selected geometric pattern. Varying phase and voltages configurations are applied to corresponding electrodes to achieve heating, physical phase changes, and the placement of substances within the treatment region. Additionally, treatment mediums can be added to either treat the contamination within the soil or to restrict their mobility. 29 figs.

Endotoxin contamination and control in surface water sources and a drinking water treatment plant in Beijing, China.

PubMed

Can, Zhang; Wenjun, Liu; Wen, Sun; Minglu, Zhang; Lingjia, Qian; Cuiping, Li; Fang, Tian

2013-07-01

In this paper, endotoxin contamination was determined in treated water following each unit of a drinking water treatment plant (WTP) in Beijing, China and its source water (SW) from a long water diversion channel (Shijiazhuang-Beijing) originating from four reservoirs in Hebei province, China. The total-endotoxin activities in SW ranged from 21 to 41 EU/ml at five selected cross sections of the diversion channel. The total-endotoxin in raw water of the WTP ranged from 11 to 16 EU/ml due to dilution and pretreatment during water transportation from Tuancheng Lake to the WTP, and finished water of the WTP ranged from 4 to 10 EU/ml, showing a 49% decrease following the full-scale treatment process at the WTP. Compared with the 31% removal of free-endotoxin, the WTP removed up to 71% of bound-endotoxin in raw water. The traditional treatment processes (coagulation, sedimentation and filtration) in the WTP removed substantial amounts of total-endotoxin (up to 63%), while endotoxin activities increased after granular activated carbon (GAC) adsorption and chlorination. The total-endotoxin in the actual water was composed of free-endotoxin and bound-endotoxin (endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins). The endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins co-exist as suspended particles in water, and only the bacteria-bound endotoxins were correlated with bacterial cells suspended in water. The particle distribution of endotoxin aggregates in ultrapure water was also tested and the results showed that the majority (64-89%) of endotoxin aggregates had diameters <2 μm. The endotoxin contamination and control in treated water following each unit of the WTP processes and its SW from reservoirs are discussed and compared with regard to bacterial cell counts and particle characteristics, which were dependent, to a certain extent, on different flow rates and turbulence of the water environments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Methods for microbial filtration of fluids

DOEpatents

Carman, M.L.; Jackson, K.J.; Knapp, R.B.; Knezovich, J.P.; Shah, N.N.; Taylor, R.T.

1996-01-30

Novel methods for purifying contaminated subsurface groundwater are disclosed. The method is involves contacting the contaminated subsurface groundwater with methanotrophic or heterotrophic microorganisms which produce contaminant-degrading enzymes. The microorganisms are derived from surface cultures and are injected into the ground so as to act as a biofilter. The contaminants which may be treated include organic or metallic materials and radionuclides. 8 figs.

Transfer of wastewater associated pharmaceuticals and personal care products to crop plants from biosolids treated soil.

PubMed

Wu, Chenxi; Spongberg, Alison L; Witter, Jason D; Sridhar, B B Maruthi

2012-11-01

The plant uptake of emerging organic contaminants such as pharmaceuticals and personal care products (PPCPs) is receiving increased attention. Biosolids from municipal wastewater treatment have been previously identified as a major source for PPCPs. Thus, plant uptake of PPCPs from biosolids applied soils needs to be understood. In the present study, the uptake of carbamazepine, diphenhydramine, and triclocarban by five vegetable crop plants was examined in a field experiment. At the time of harvest, three compounds were detected in all plants grown in biosolids-treated soils. Calculated root concentration factor (RCF) and shoot concentration factor (SCF) are the highest for carbamazepine followed by triclocarban and diphenhydramine. Positive correlation between RCF and root lipid content was observed for carbamazepine but not for diphenhydramine and triclocarban. The results demonstrate the ability of crop plants to accumulate PPCPs from contaminated soils. The plant uptake processes of PPCPs are likely affected by their physico-chemical properties, and their interaction with soil. The difference uptake behavior between plant species could not solely be attributed to the root lipid content. Copyright © 2012 Elsevier Inc. All rights reserved.

Application of ultrafiltration in the pulp and paper industry: metals removal and whitewater reuse.

PubMed

Oliveira, C R; Silva, C M; Milanez, A F

2007-01-01

In the pulp and paper industry, the water use minimization is a constant target. One way to reduce water use is to recycle the effluent in a closed-cycle concept. In paper mills, the main source of liquid effluent is the so-called whitewater, which is the excess water, originated from pulp stock dewatering and other fibre contaminated water. This research studied the reuse of paper mill whitewater after membrane ultrafiltration (UF) in the paper machine and in the pulp bleach plant of an integrated mill. Contaminant removal and flux behaviour of the UF system were evaluated. The treatment by ultrafiltration was technically feasible and the treated whitewater had good potential to be reused in some processes in the paper machine. The reuse of ultrafiltered whitewater in the bleaching plant was not recommended because of the high level of soluble calcium present in this stream. Therefore, a combined treatment of the whitewater using the principle of precipitation and ultrafiltration was proposed showing good results and enabling the use of the treated whitewater in the bleach plant.

SURFACTANT SELECTION FOR ENHANCING EX SITU SOIL WASHING. (R825511C064)

EPA Science Inventory

Ex situ soil washing is commonly used for treating contaminated soils by separating the most contaminated fraction of the soil for disposal. Surfactant-enhanced soil washing is being considered with increasing frequency to actually achieve soil-contaminant separation. I...

Estimation of Unsaturated Zone Traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, Using a Source-Responsive Preferential-Flow Model

USGS Publications Warehouse

Ebel, Brian A.; Nimmo, John R.

2009-01-01

Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated zone takes place as preferential flow, faster than would be predicted by the coupled Richards' and advection-dispersion equations with hydraulic properties estimated by traditional means. At present the hydrologic community has not achieved consensus as to whether a modification of Richards' equation, or a fundamentally different formulation, would best quantify preferential flow. Where the fastest contaminant transport speed is what needs to be estimated, there is the possibility of simplification of the evaluation process. One way of doing so is by a two-step process in which the first step is to evaluate whether significant preferential flow and solute transport is possible for the media and conditions of concern. The second step is to carry out (a) a basic Richards' and advection-dispersion equation analysis if it is concluded that preferential flow is not possible or (b) an analysis that considers only the fastest possible preferential-flow processes, if preferential flow is possible. For the preferential-flow situation, a recently published model describable as a Source-Responsive Preferential-Flow (SRPF) model is an easily applied option. This report documents the application of this two-step process to flow through the thick unsaturated zones of Rainier Mesa and Shoshone Mountain in the Nevada Test Site. Application of the SRPF model involves distinguishing between continuous and intermittent water supply to preferential flow paths. At Rainier Mesa and Shoshone Mountain this issue is complicated by the fact that contaminant travel begins at a location deep in the subsurface, where there may be perched water that may or may not act like a continuous supply, depending on such features as the connectedness of fractures and the nature of impeding layers. We have treated this situation by hypothesizing both continuous and intermittent scenarios for contaminant transport to the carbonate aquifer and reporting estimation of the fastest speed for both of th

Estimation of unsaturated zone traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, using a source-responsive preferential-flow model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brian A. Ebel; John R. Nimmo

2009-09-11

Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travelmore » within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated zone takes place as preferential flow, faster than would be predicted by the coupled Richards' and advection-dispersion equations with hydraulic properties estimated by traditional means. At present the hydrologic community has not achieved consensus as to whether a modification of Richards' equation, or a fundamentally different formulation, would best quantify preferential flow. Where the fastest contaminant transport speed is what needs to be estimated, there is the possibility of simplification of the evaluation process. One way of doing so is by a two-step process in which the first step is to evaluate whether significant preferential flow and solute transport is possible for the media and conditions of concern. The second step is to carry out (a) a basic Richards' and advection-dispersion equation analysis if it is concluded that preferential flow is not possible or (b) an analysis that considers only the fastest possible preferential-flow processes, if preferential flow is possible. For the preferential-flow situation, a recently published model describable as a Source-Responsive Preferential-Flow (SRPF) model is an easily applied option. This report documents the application of this two-step process to flow through the thick unsaturated zones of Rainier Mesa and Shoshone Mountain in the Nevada Test Site. Application of the SRPF model involves distinguishing between continuous and intermittent water supply to preferential flow paths. At Rainier Mesa and Shoshone Mountain this issue is complicated by the fact that contaminant travel begins at a location deep in the subsurface, where there may be perched water that may or may not act like a continuous supply, depending on such features as the connectedness of fractures and the nature of impeding layers. We have treated this situation by hypothesizing both continuous and intermittent scenarios for contaminant transport to the carbonate aquifer and reporting estimation of the fastest speed for both of these end members.« less

Pilot plant experiences using physical and biological treatment steps for the remediation of groundwater from a former MGP site.

PubMed

Wirthensohn, T; Schoeberl, P; Ghosh, U; Fuchs, W

2009-04-15

The production of manufactured gas at a site in Vienna, Austria led to the contamination of soil and groundwater with various pollutants including PAHs, hydrocarbons, phenols, BTEX, and cyanide. The site needs to be remediated to alleviate potential impacts to the environment. The chosen remediation concept includes the excavation of the core contaminated site and the setup of a hydraulic barrier to protect the surrounding aquifer. The extracted groundwater will be treated on-site. To design the foreseen pump-and-treat system, a pilot-scale plant was built and operated for 6 months. The scope of the present study was to test the effectiveness of different process steps, which included an aerated sedimentation basin, a submerged fixed film reactor (SFFR), a multi-media filter, and an activated carbon filter. The hydraulic retention time (HRT) was 7.0 h during normal flow conditions and 3.5h during high flow conditions. The treatment system was effective in reducing the various organic and inorganic pollutants in the pumped groundwater. However, it was also demonstrated that appropriate pre-treatment was essential to overcome problems with clogging due to precipitation of tar and sulfur compounds. The reduction of the typical contaminants, PAHs and BTEX, was more than 99.8%. All water quality parameters after treatment were below the Austrian legal requirements for discharge into public water bodies.

Introduction to Exide Corporations`s high temperature metals recovery system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rozelle, P.L.; Baranski, J.P.; Bitler, J.A.

1995-12-31

Environmental strategies concerning the processing and ultimate fate of wastes and byproducts are of ever increasing importance to the public and business sectors in the world today. Recycling materials and reusing energy from wastes and byproducts results in a reduction of environmental impacts and the cost of disposal. These are the key steps in reaching the ultimate goal of waste minimization. In response to these needs, Exide Corporation, in its vision to develop waste minimization programs, has developed the Exide High Temperature Metals Recovery (EHTMR) process. This process can treat a variety of wastes and byproducts where metals contents aremore » an issue, recover the metal values for reuse, and produce a metals-depleted slag that can be marketable under the most stringent proposed EPA regulations for leachability of contaminants. The central feature of the EHTMR process is the exposure of treated materials to a transferred arc plasma generated in an electric furnace. The process achieves a reduction in costs and liability by recovering portions of a waste that can be recycled or reclaimed and produces a slag that has beneficial use to society.« less

An innovative method for the solidification/stabilization of PAHs-contaminated soil using sulfonated oil.

PubMed

Ma, Fujun; Wu, Bin; Zhang, Qian; Cui, Deshan; Liu, Qingbing; Peng, Changsheng; Li, Fasheng; Gu, Qingbao

2018-02-15

Stabilization/solidification (S/S) has been successfully employed in many superfund sites contaminated with organic materials. However, this method's long-term effectiveness has not been fully evaluated and the increase in soil volume following treatment is unfavorable to follow-up disposal. The present study developed a novel method for the S/S of PAHs-contaminated soil with the facilitation of sulfonated oil (SO). Adding SO significantly improved the unconfined compressive strength (UCS) values of Portland cement and activated carbon (PC-AC) treated soil samples, and the UCS values of the soil sample treated with 0.02% of SO were up to 2.3 times higher than without SO addition. When the soil was treated with PC-AC-SO, the PAHs leaching concentrations were 14%-25% of that in leachates of the control soil, and high molecular weight PAHs including benzo(a)pyrene were rarely leached. Freeze/thaw durability tests reveal that the leachability of PAHs was not influenced by freeze-thaw cycles. The UCS values of PC-AC-SO treated soil samples were 2.2-3.4 times greater than those of PC-AC treated soil samples after 12 freeze-thaw cycles. The PC-AC-SO treated soils resist disintegration better when compared to the PC-AC treated soils. The SEM micrographs reveal that the soils' compactness was significantly improved when treated with SO. Copyright © 2017 Elsevier B.V. All rights reserved.

Nationwide reconnaissance of contaminants of emerging ...

EPA Pesticide Factsheets

When chemical or microbial contaminants are assessed for potential effect or possible regulation in ambient and drinking waters, a critical first step is determining if the contaminants occur and if they are at concentrations that may cause human or ecological health concerns. To this end, source and treated drinking water samples from 29 drinking water treatment plants (DWTPs) were analyzed as part of a two-phase study to determine whether chemical and microbial constituents, many of which are considered contaminants of emerging concern, were detectable in the waters. Of the 84 chemicals monitored in the 9 Phase I DWTPs, 27 were detected at least once in the source water, and 21 were detected at least once in treated drinking water. In Phase II, which was a broader and more comprehensive assessment, 247 chemical and microbial analytes were measured in 25 DWTPs, with 148 detected at least once in the source water, and 121 detected at least once in the treated drinking water. The frequency of detection was often related to the analyte's contaminant class, as pharmaceuticals and anthropogenic waste indicators tended to be infrequently detected and more easily removed during treatment, while per and polyfluoroalkyl substances and inorganic constituents were both more frequently detected and, overall, more resistant to treatment. The data collected as part of this project will be used to help inform evaluation of unregulated contaminants in surface water, groundwate

Development of the CROW{trademark} process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, L.A. Jr.

1994-05-01

The Contained Recovery of Oily Waste (CROW{trademark}) technology has been successfully tested in the laboratory and presently is being implemented at field sites contaminated with wood treating wastes and byproducts of town gas production. These field demonstrations will utilize only hot-water displacement without any chemical additives because the use of chemicals to enhance the hot-water flushing process has only been tested on a preliminary basis. Preliminary testing has shown that low concentrations of chemicals could reduce the contaminant content by an additional 10 to 20 wt %. Western Research Institute (WRI) research, plus research at Carnegie Mellon University, on surfactantmore » enhancement of solubility of polynuclear aromatic hydrocarbons in water and water-soil systems indicate the potential of chemical enhancement of the CROW process. Chemicals that have been tested and that were used in these tests are totally biodegradable. The objective of this task was to obtain sufficient baseline data to show the effectiveness and environmentally safe use of chemicals, primarily surfactants, to enhance the CROW process. To meet this objective, 14 one-dimensional displacement tests were conducted. Eleven tests were conducted on a material from a former manufactured gas plant (MGP) site and four tests were conducted with a contaminated soil from a former wood treatment facility. The tests investigated the effect of three chemical concentrations (0, 0.5, and 1.0 vol %) at three temperatures (ambient, the projected optimum temperature, and one 40{degree}F [22{degree}C] below the optimum temperature).« less

Effect of air polishing with glycine powder on titanium abutment surfaces.

PubMed

Cochis, Andrea; Fini, Milena; Carrassi, Antonio; Migliario, Mario; Visai, Livia; Rimondini, Lia

2013-08-01

The aim of the present study was to evaluate morphological changes induced by glycine powder air polishing on titanium surfaces and its effect on bacteria recolonization in comparison with sodium bicarbonate powder. 5 mm wide and 1 mm thick titanium grade II disks were divided into three groups of treatments: (i) no treatment; (ii) air polishing with glycine powder; (iii) air polishing with sodium bicarbonate powder. Specimens were characterized by laser profilometry, scanning electron microscopy (SEM) and then installed onto removable appliances worn for 24 h by healthy volunteers. Surface contamination was evaluated using SEM and counting the number of colony forming units (CFU). SEM observation revealed an increased roughness with the formation of craters on samples treated with sodium bicarbonate powder, while not in glycine ones. Statistical analysis failed to show significant differences of both Ra and Rmax parameters in treated groups. SEM observation of specimens surfaces, after 24 h of permanence in the oral cavity, showed a higher contamination of the disks treated with sodium bicarbonate compared with those not treated (P < 0.05). Conversely, the group treated with glycine showed the lower contamination if compared with bicarbonate-treated group (P < 0.05). Air polishing with glycine powder may be considered as a better method to remove plaque from dental implant because glycine is less aggressive than sodium bicarbonate powder. Moreover, the use of glycine powder seems to have an active role on the inhibition of bacterial recolonization of implants in a short test period (24 h). Further studies are needed to demonstrate the bacteriostatic properties of glycine, envisaged on the basis of reduced contamination of the disks polished with glycine compared with those not treated. © 2012 John Wiley & Sons A/S.

Evaluation of Bacteriophage Application to Cattle in Lairage at Beef Processing Plants to Reduce Escherichia coli O157:H7 Prevalence on Hides and Carcasses.

PubMed

Arthur, Terrance M; Kalchayanand, Norasak; Agga, Getahun E; Wheeler, Tommy L; Koohmaraie, Mohammad

2017-01-01

Escherichia coli O157:H7 is a major food safety concern for the beef industry. Several studies have provided evidence that cattle hides are the main source of beef carcass contamination during processing and that reductions in the E. coli O157:H7 load on the hides of cattle entering processing facilities will lead to reductions in carcass contamination. Bacteriophages have been proposed as a novel preharvest antimicrobial intervention to reduce the levels of E. coli O157:H7 on cattle hides. The objective of this study was to evaluate a commercialized phage application administered in the lairage area of commercial beef processing plants for the ability to reduce E. coli O157:H7 contamination of cattle hides and carcasses. Cattle lots either received phage spray treatment (n = 289) or did not (n = 301), as they entered the lairage environments in two separate experiments at two different commercial beef processing plants. Hide and carcass samples were collected and analyzed for E. coli O157:H7 prevalence and concentration. Cattle hides receiving phage treatment had an E. coli O157:H7 prevalence of 51.8%, whereas untreated hides had a prevalence of 57.6%. For carcass samples, the E. coli O157 prevalence in treated and untreated samples was 17.1% and 17.6%, respectively. The results obtained from these experiments demonstrated that the treatment of cattle hides with bacteriophages before processing did not produce a significant reduction of E. coli O157:H7 on cattle hides or beef carcasses during processing.

Plasma-induced grafting of acrylic acid on bentonite for the removal of U(VI) from aqueous solution

NASA Astrophysics Data System (ADS)

Hongshan, ZHU; Shengxia, DUAN; Lei, CHEN; Ahmed, ALSAEDI; Tasawar, HAYAT; Jiaxing, LI

2017-11-01

Fabrication of reusable adsorbents with satisfactory adsorption capacity and using environment-friendly preparation processes is required for the environment-related applications. In this study, acrylic acid (AA) was grafted onto bentonite (BT) to generate an AA-graft-BT (AA-g-BT) composite using a plasma-induced grafting technique considered to be an environment-friendly method. The as-prepared composite was characterized by scanning electron microscopy, x-ray powder diffraction, thermal gravity analysis, Fourier transform infrared spectroscopy and Barrett-Emmett-Teller analysis, demonstrating the successful grafting of AA onto BT. In addition, the removal of uranium(VI) (U(VI)) from contaminated aqueous solutions was examined using the as-prepared composite. The influencing factors, including contact time, pH value, ionic strength, temperature, and initial concentration, for the removal of U(VI) were investigated by batch experiments. The experimental process fitted best with the pseudo-second-order kinetic and the Langmuir models. Moreover, thermodynamic investigation revealed a spontaneous and endothermic process. Compared with previous adsorbents, AA-g-BT has potential practical applications in treating U(VI)-contaminated solutions.

Stabilization and disposal of Argonne-West low-level mixed wastes in ceramicrete waste forms.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barber, D. B.; Singh, D.; Strain, R. V.

1998-02-17

The technology of room-temperature-setting phosphate ceramics or Ceramicrete{trademark} technology, developed at Argonne National Laboratory (ANL)-East is being used to treat and dispose of low-level mixed wastes through the Department of Energy complex. During the past year, Ceramicrete{trademark} technology was implemented for field application at ANL-West. Debris wastes were treated and stabilized: (a) Hg-contaminated low-level radioactive crushed light bulbs and (b) low-level radioactive Pb-lined gloves (part of the MWIR {number_sign} AW-W002 waste stream). In addition to hazardous metals, these wastes are contaminated with low-level fission products. Initially, bench-scale waste forms with simulated and actual waste streams were fabricated by acid-base reactionsmore » between mixtures of magnesium oxide powders and an acid phosphate solution, and the wastes. Size reduction of Pb-lined plastic glove waste was accomplished by cryofractionation. The Ceramicrete{trademark} process produces dense, hard ceramic waste forms. Toxicity Characteristic Leaching Procedure (TCLP) results showed excellent stabilization of both Hg and Pb in the waste forms. The principal advantage of this technology is that immobilization of contaminants is the result of both chemical stabilization and subsequent microencapsulation of the reaction products. Based on bench-scale studies, Ceramicrete{trademark} technology has been implemented in the fabrication of 5-gal waste forms at ANL-West. Approximately 35 kg of real waste has been treated. The TCLP is being conducted on the samples from the 5-gal waste forms. It is expected that because the waste forms pass the limits set by the EPAs Universal Treatment Standard, they will be sent to a radioactive-waste disposal facility.« less

Fluorescence tracers as a reference for pesticide transport in wetland systems

NASA Astrophysics Data System (ADS)

Lange, Jens; Passeport, Elodie; Tournebize, Julien

2010-05-01

Two different fluorescent tracers, Uranine (UR) and Sulforhodamine (SRB), were injected as a pulse into surface flow wetlands. Tracer breakthrough curves were used to document hydraulic efficiencies, peak attenuation and retention capacities of completely different wetland systems. The tracers were used as a reference to mimic photolytic decay (UR) and sorption (SRB) of contaminants, since a real herbicide (Isoproturon, IPU) was injected in parallel to UR and SRB. Analysis costs limited IPU sampling frequency and single samples deviated from the tracer breakthrough curves. Still, a parallel behavior of IPU and SRB could be observed in totally different wetland systems, including underground passage through drainage lines. Similar recovery rates for IPU and SRB confirmed this observation. Hence, SRB was found to be an appropriate reference tracer to mimic the behavior of mobile pesticides (low KOC, without degradation) in wetland systems and the obtained wetland characteristics for SRB may serve as an indication for contaminant retention. Owing to the properties of IPU, the obtained results should be treated as worst case scenarios for highly mobile pesticides. A comparison of six different wetland types suggested that non-steady wetland systems with large variation in water level may temporally store relatively large amounts of tracers (contaminants), partly in areas that are not continuously saturated. This may lead to an efficient attenuation of peak concentrations. However, when large parts of these systems are flushed by natural storm events, tracers (contaminants) may be re-mobilized. In steady systems vegetation density and water depth were found to be the most important factors for tracer/contaminant retention. Illustrated by SRB, sorption on sediments and vegetation was a quick, almost instantaneous process which lead to considerable tracer losses even at high flow velocities and short contact times. Shallow systems with dense vegetation appeared to be the most efficient SRB/contaminant traps. For photolytic decay no reference contaminant was studied, but the results found for UR may serve as a valuable proxy for this process.

Bioremediation of petroleum hydrocarbon-contaminated ground water: The perspectives of history and hydrology

USGS Publications Warehouse

Chapelle, F.H.

1999-01-01

Bioremediation, the use of microbial degradation processes to detoxify environmental contamination, was first applied to petroleum hydrocarbon-contaminated ground water systems in the early 1970s. Since that time, these technologies have evolved in some ways that were clearly anticipated early investigators, and in other ways that were not foreseen. The expectation that adding oxidants and nutrients to contaminated aquifers would enhance biodegradation, for example, has been born out subsequent experience. Many of the technologies now in common use such as air sparging, hydrogen peroxide addition, nitrate addition, and bioslurping, are conceptually similar to the first bioremediation systems put into operation. More unexpected, however, were the considerable technical problems associated with delivering oxidants and nutrients to heterogeneous ground water systems. Experience has shown that the success of engineered bioremediation systems depends largely on how effectively directions and rates of ground water flow can be controlled, and thus how efficiently oxidants and nutrients can be delivered to contaminated aquifer sediments. The early expectation that injecting laboratory-selected or genetically engineered cultures of hydrocarbon-degrading bacteria into aquifers would be a useful bioremediation technology has not been born out subsequent experience. Rather, it appears that petroleum hydrocarbon-degrading bacteria are ubiquitous in ground water systems and that bacterial addition is usually unnecessary. Perhaps the technology that was least anticipated early investigators was the development of intrinsic bioremediation. Experience has shown that natural attenuation mechanisms - biodegradation, dilution, and sorption - limit the migration of contaminants to some degree in all ground water systems. Intrinsic bioremediation is the deliberate use of natural attenuation processes to treat contaminated ground water to specified concentration levels at predetermined points in the aquifer. In current practice, intrinsic bioremediation of petroleum hydrocarbons requires a systematic assessment to show that ambient natural attenuation mechanisms are efficient enough to meet regulatory requirements and a monitoring program to verify that performance requirements are met in the future.

Movement and fate of creosote waste in ground water, Pensacola, Florida; U.S. Geological Survey toxic waste-ground-water contamination program

USGS Publications Warehouse

Mattraw, Harold C.; Franks, Bernard J.

1986-01-01

Ground- and surface-water contamination by pesticides used in the wood-preserving industry is widespread in the United States. Pine poles were treated with wood preservatives from 1902 to 1981 at a creosote works near Pensacola, Florida. Diesel fuel, creosote, and pentachlorophenol were discharged to two unlined impoundments that had a direct hydraulic connection to the sand-and-gravel aquifer. Evidence of wood-preserving waste contamination appears to be confined to the upper 30 meters of the aquifer. The waste plume extends downgradient approximately 300 meters south toward Pensacola Bay. In 1983, the creosote works site was selected by the U.S. Geological Survey's Office of Hazardous Waste Hydrology as a national research demonstration area to apply the latest techniques for characterizing hazardous waste problems. The multidisciplinary research effort is aimed at studying processes that affect the occurrence, transport, transformations, and fate of the toxic contaminants associated with wood preservatives in the environment. Clusters of two to five wells were constructed at different depths at nine sites to define the depth of contamination. Research studies are investigating sorption, dispersion, dilution, chemical reactions, bacterially mediated transformations, quality assurance, plume hydrodynamics, and the ultimate fate of these complex organic wastes.

Effect of organic contamination upon microbial distributions and heterotrophic uptake in a cape cod, mass., aquifer

USGS Publications Warehouse

Harvey, R.W.; Smith, R.L.; George, L.

1984-01-01

Bacterial abundance, distribution, and heterotrophic uptake in a freshwater aquifer contaminated by treated sewage were determined from analyses of groundwater and sediment-core samples. The number of free-living (unattached) bacteria in contaminated groundwater declined steadily with increasing distance from the source of sewage infiltration, from 1.94 ?? (?? 0.20) x 106 ml-1 at 0.21 km to 0.25 (?? 0.02) x 106 ml-1 at 0.97 km. Bacterial abundance in groundwater sampled at 0.31 km correlated strongly with specific conductance and increased sharply from 4.0 (?? 0.3) x 104 ml-1 at a depth of 6 m to 1.58 (?? 0.12) x 106 ml-1 at 14 m, then declined at 20 and 31 m to 1.29 (?? 0.12) x 106 and 0.96 (?? 0.12) x 106 ml-1, respectively. A majority of the bacteria in contaminated and uncontaminated zones of the aquifer were bound to the surfaces of particulates, <60 ??m in diameter. The glucose uptake rate, assayed at in situ and 5 ??M concentrations, declined steadily in contaminated groundwater sampled along a transect. A preparative wet-sieving technique for use in processing core samples for bacterial enumeration is described and evaluated.

Fragmentation of contaminant and endogenous DNA in ancient samples determined by shotgun sequencing; prospects for human palaeogenomics.

PubMed

García-Garcerà, Marc; Gigli, Elena; Sanchez-Quinto, Federico; Ramirez, Oscar; Calafell, Francesc; Civit, Sergi; Lalueza-Fox, Carles

2011-01-01

Despite the successful retrieval of genomes from past remains, the prospects for human palaeogenomics remain unclear because of the difficulty of distinguishing contaminant from endogenous DNA sequences. Previous sequence data generated on high-throughput sequencing platforms indicate that fragmentation of ancient DNA sequences is a characteristic trait primarily arising due to depurination processes that create abasic sites leading to DNA breaks. METHODOLOGY/PRINCIPALS FINDINGS: To investigate whether this pattern is present in ancient remains from a temperate environment, we have 454-FLX pyrosequenced different samples dated between 5,500 and 49,000 years ago: a bone from an extinct goat (Myotragus balearicus) that was treated with a depurinating agent (bleach), an Iberian lynx bone not subjected to any treatment, a human Neolithic sample from Barcelona (Spain), and a Neandertal sample from the El Sidrón site (Asturias, Spain). The efficiency of retrieval of endogenous sequences is below 1% in all cases. We have used the non-human samples to identify human sequences (0.35 and 1.4%, respectively), that we positively know are contaminants. We observed that bleach treatment appears to create a depurination-associated fragmentation pattern in resulting contaminant sequences that is indistinguishable from previously described endogenous sequences. Furthermore, the nucleotide composition pattern observed in 5' and 3' ends of contaminant sequences is much more complex than the flat pattern previously described in some Neandertal contaminants. Although much research on samples with known contaminant histories is needed, our results suggest that endogenous and contaminant sequences cannot be distinguished by the fragmentation pattern alone.

House hold unit for the treatment of fluoride, iron, arsenic and microorganism contaminated drinking water.

PubMed

Dhadge, Vijaykumar L; Medhi, Chitta Ranjan; Changmai, Murchana; Purkait, Mihir Kumar

2018-05-01

A first of its kind hybrid electrocoagulation-filtration prototype unit was fabricated for the removal of fluoride, iron, arsenic and microorganisms contaminated drinking water. The unit comprised of 3 chambers, chamber A consisting of an inlet for the water to be treated and an outlet for the treated water along with one block of aluminum electrodes. Chamber B consisted of ceramic membrane filtration assembly at the bottom over a metallic support which filters the flocs so produced in chamber A and chamber C consisting of space to collect the treated water. Operating parameters were maintained as current density of 625 A m -2 and an electrode distance of 0.005 m. Contaminated drinking water containing mixture of fluoride (10 mg L -1 ), iron (25 mg L -1 ), arsenic (200 μg L -1 ) and microorganisms (35 CFU ml -1 ) was used for the experiment. A removal of 98.74%, 95.65%, 93.2% and 100% were obtained for iron, arsenic, fluoride and microorganisms, respectively. The apparatus and method made it possible to efficiently treat contaminated drinking water to produce drinkable water as per WHO specification. By-products obtained from the electrocoagulation bath were analyzed using SEM, EDX and XRD and explained. Copyright © 2018 Elsevier Ltd. All rights reserved.

Photocatalytic Oxidation of Oil Contaminated Water Using TiO2/UV

NASA Astrophysics Data System (ADS)

Vargas Solla, Monica; Romero Rojas, Jairo

2017-04-01

Currently, oil is one of the most used energy sources all around the world, for example to make motor engines work. That prevailing usage of oil is the reason why water sources are under serious pollution risks with compounds that are hard to remove, such as hydrocarbons. There are a few water treatment processes known as Advanced Oxidation Processes, which search for a way to treat polluted water with toxic refractory compounds, to make its reuse more feasible and to avoid or at least appease the injurious effects of pollution over ecosystems. A heterogeneous photocatalysis water treatment technology, sorted as an Advanced Oxidation Process, which is intended to treat refractory compound polluted water by the use of TiO2 and UV light, is presented in this investigation. The evidence about its efficiency in hydrocarbon removal from used motor oil polluted water, since it is an extremely important pollutant due to its complexity, toxicity and recalcitrant characteristics, is also presented through COD, Oil and Grease and Hydrocarbons analysis.

Modelling biological Cr(VI) reduction in aquifer microcosm column systems.

PubMed

Molokwane, Pulane E; Chirwa, Evans M N

2013-01-01

Several chrome processing facilities in South Africa release hexavalent chromium (Cr(VI)) into groundwater resources. Pump-and-treat remediation processes have been implemented at some of the sites but have not been successful in reducing contamination levels. The current study is aimed at developing an environmentally friendly, cost-effective and self-sustained biological method to curb the spread of chromium at the contaminated sites. An indigenous Cr(VI)-reducing mixed culture of bacteria was demonstrated to reduce high levels of Cr(VI) in laboratory samples. The effect of Cr(VI) on the removal rate was evaluated at concentrations up to 400 mg/L. Following the detailed evaluation of fundamental processes for biological Cr(VI) reduction, a predictive model for Cr(VI) breakthrough through aquifer microcosm reactors was developed. The reaction rate in batch followed non-competitive rate kinetics with a Cr(VI) inhibition threshold concentration of approximately 99 mg/L. This study evaluates the application of the kinetic parameters determined in the batch reactors to the continuous flow process. The model developed from advection-reaction rate kinetics in a porous media fitted best the effluent Cr(VI) concentration. The model was also used to elucidate the logistic nature of biomass growth in the reactor systems.

Calculation of the compounded uncertainty of 14C AMS measurements

NASA Astrophysics Data System (ADS)

Nadeau, Marie-Josée; Grootes, Pieter M.

2013-01-01

The correct method to calculate conventional 14C ages from the carbon isotopic ratios was summarised 35 years ago by Stuiver and Polach (1977) and is now accepted as the only method to calculate 14C ages. There is, however, no consensus regarding the treatment of AMS data, mainly of the uncertainty of the final result. The estimation and treatment of machine background, process blank, and/or in situ contamination is not uniform between laboratories, leading to differences in 14C results, mainly for older ages. As Donahue (1987) and Currie (1994), among others, mentioned, some laboratories find it important to use the scatter of several measurements as uncertainty while others prefer to use Poisson statistics. The contribution of the scatter of the standards, machine background, process blank, and in situ contamination to the uncertainty of the final 14C result is also treated in different ways. In the early years of AMS, several laboratories found it important to describe their calculation process in details. In recent years, this practise has declined. We present an overview of the calculation process for 14C AMS measurements looking at calculation practises published from the beginning of AMS until present.

Base Program on Energy Related Research

NASA Astrophysics Data System (ADS)

1998-07-01

The Base Research Program at Western Research Institute (WRI) is planned to develop technologies to a level that will attract industrial sponsors for continued development under the Jointly Sponsored Research (JSR) Program. The Base Cooperative Agreement (DE-FC26-98FT40322) was initiated on April 10, with funding of 500,000.Tasks approved for funding, FY 98 include the following: 1.1 CROW Process Application for Sites Contaminated With LNAPL and Chlorinated Solvents -50,000; 1.2 Petroleum residual Solubility Parameter/Polarity Map-75,000; 1.3 Laboratory and Bench-Scale Testing for Treating Used Motor Oil-135,000; 1.4 Development and Testing of a Coal-Fired Gas Turbine System- 140,000; 2.1 Evaluation of a Method Using Colloidal Gas Aphrons to Remediate Metals-Contaminated Mine Drainage Waters-15,000; 2.2 Development of a Procedure for Production of a Protective Covering for PEAC Units - 15,000; and 3.1 Heavy Oil/Plastics Co-Processing -70,000 TOTALS-500,000

Reactive Radial Diffusion Model for the Aging/Sequestration Process

NASA Astrophysics Data System (ADS)

Ginn, T. R.; Basagaoglu, H.; McCoy, B. J.; Scow, K. M.

2001-12-01

A radial diffusion model has been formulated to simulate age-dependent bioavailability of chemical compounds to micro-organisms residing outside (and/or inside) the porous soil particles. Experimental findings in the literature indicate that the sequestration and reduction in bioavailability of contaminants are controlled presumably by the diffusion-limited sorption kinetics and the time-variant desorption process. Here we combine radial-diffusion mass transfer modeling with the exposure-time concept to generate mass-balance equations for the intra- and extra-particle concentrations. The model accomodates reversible sorption kinetics involving sorption time-dependence of the rate coefficients, distinct intra- and extra-particle biodegradation rates; and a dynamic mass interaction between the intra- and extra-particle concentrations arising from the radial diffusion concept. The model explicitly treats multiple particle classes distributed in size and chemical properties in a bulk aquifer or soil volume, which allows the simulation of the sequestration and bioavailability of contaminants in different particle size classes that have distinct diffusion, reaction, and aging properties.

Optimisation of surfactant decontamination and pre-treatment of waste chicken feathers by using response surface methodology.

PubMed

Tesfaye, Tamrat; Sithole, Bruce; Ramjugernath, Deresh; Ndlela, Luyanda

2018-02-01

Commercially processed, untreated chicken feathers are biologically hazardous due to the presence of blood-borne pathogens. Prior to valorisation, it is crucial that they are decontaminated to remove the microbial contamination. The present study focuses on evaluating the best technologies to decontaminate and pre-treat chicken feathers in order to make them suitable for valorisation. Waste chicken feathers were washed with three surfactants (sodium dodecyl sulphate) dimethyl dioctadecyl ammonium chloride, and polyoxyethylene (40) stearate) using statistically designed experiments. Process conditions were optimised using response surface methodology with a Box-Behnken experimental design. The data were compared with decontamination using an autoclave. Under optimised conditions, the microbial counts of the decontaminated and pre-treated chicken feathers were significantly reduced making them safe for handling and use for valorisation applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Polychlorinated biphenyl concentrations in Hudson River water and treated drinking water at Waterford, New York

USGS Publications Warehouse

Schroeder, R.A.; Barnes, C.R.

1983-01-01

Past discharge of PCBs into the Hudson River has resulted in contaminant concentrations of a few tenths of a microgram per liter in the water. Waterford is one of two large municipal users of the Hudson River for drinking-water supply. The treatment scheme at the Waterford plant, which processes approximately 1 million gallons per day, is similar to that of most conventional treatment plants except for the addition of powdered activated carbon during flocculation. Comparison of PCB concentrations in river water and intake water at the plant to concentrations in treated drinking-water samples indicates that purification processes remove 80 to 90 percent of the PCBs and that final concentrations seldom exceed 0.1 microgram per liter. No significant difference was noted between the removal efficiencies during periods of high river discharge, when PCBs are associated with suspended sediment, and low discharge, when PCBs are generally dissolved. (USGS)

Bioremediation of diesel from a rocky shoreline in an arid tropical climate.

PubMed

Guerin, Turlough F

2015-10-15

A non invasive sampling and remediation strategy was developed and implemented at shoreline contaminated with spilt diesel. To treat the contamination, in a practical, cost-effective, and safe manner (to personnel working on the stockpiles and their ship loading activity), a non-invasive sampling and remediation strategy was designed and implemented since the location and nature of the impacted geology (rock fill) and sediment, precluded conventional ex-situ and any in-situ treatment where drilling is required. A bioremediation process using surfactant, and added N & P and increased aeration, increased the degradation rate allowing the site owner to meet their regulatory obligations. Petroleum hydrocarbons decreased from saturation concentrations to less than detectable amounts at the completion of treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

TECHNICAL APPROACHES TO CHARACTERIZING AND ...

EPA Pesticide Factsheets

The document provides brownfields planners with an overview of the technical methods that can be used to achieve successful site assessment and cleanup which are two key components of the brownfields redevelopment process. No two brownfields sites are identical and planners will need to base assessment and cleanup activities on the conditions of the particular sites with which they are dealing. A site assessment strategy should address: the type and extent of contamination, if any, that is present, the types of data needed to adequately assess the site; appropriate sampling and analytical methods to characterize the contamination; acceptable level of uncertainty and cleanup technologies that contain or treat the types of wastes present.This document includes references to state agency roles including the Voluntary Cleanup Program, public involvement and other guidances that may be used. Information

Human Health Screening and Public Health Significance of Contaminants of Emerging Concern Detected in Public Water Supplies

EPA Science Inventory

The source water and treated drinking water from twenty five drinking water treatment plants (DWTPs) across the United States were sampled in 2010 – 2012. Samples were analyzed for 247 contaminants using 15 chemical and microbiological methods. Most of these contaminants are no...

Nationwide reconnaissance of contaminants of emerging concern in source and treated drinking waters of the United States

EPA Science Inventory

When chemical or microbial contaminants are assessed for potential effect or possible regulation in ambient and drinking waters, a critical first step is determining if the contaminants occur and if they are at concentrations that may cause human or ecological health concerns. To...

Characterization and Low-Cost Remediation of Soils Contaminated by Timbers in Community Gardens.

PubMed

Heiger-Bernays, W; Fraser, A; Burns, V; Diskin, K; Pierotti, D; Merchant-Borna, K; McClean, M; Brabander, D; Hynes, H P

2009-01-01

Urban community gardens worldwide provide significant health benefits to those gardening and consuming fresh produce from them. Urban gardens are most often placed in locations and on land in which soil contaminants reflect past practices and often contain elevated levels of metals and organic contaminants. Garden plot dividers made from either railroad ties or chromated copper arsenate (CCA) pressure treated lumber contribute to the soil contamination and provide a continuous source of contaminants. Elevated levels of polycyclic aromatic hydrocarbons (PAHs) derived from railroad ties and arsenic from CCA pressure treated lumber are present in the gardens studied. Using a representative garden, we 1) determined the nature and extent of urban community garden soil contaminated with PAHs and arsenic by garden timbers; 2) designed a remediation plan, based on our sampling results, with our community partner guided by public health criteria, local regulation, affordability, and replicability; 3) determined the safety and advisability of adding city compost to Boston community gardens as a soil amendment; and 4) made recommendations for community gardeners regarding healthful gardening practices. This is the first study of its kind that looks at contaminants other than lead in urban garden soil and that evaluates the effect on select soil contaminants of adding city compost to community garden soil.

Rapid and effective decontamination of chlorophenol-contaminated soil by sorption into commercial polymers: concept demonstration and process modeling.

PubMed

Tomei, M Concetta; Mosca Angelucci, Domenica; Ademollo, Nicoletta; Daugulis, Andrew J

2015-03-01

Solid phase extraction performed with commercial polymer beads to treat soil contaminated by chlorophenols (4-chlorophenol, 2,4-dichlorophenol and pentachlorophenol) as single compounds and in a mixture has been investigated in this study. Soil-water-polymer partition tests were conducted to determine the relative affinities of single compounds in soil-water and polymer-water pairs. Subsequent soil extraction tests were performed with Hytrel 8206, the polymer showing the highest affinity for the tested chlorophenols. Factors that were examined were polymer type, moisture content, and contamination level. Increased moisture content (up to 100%) improved the extraction efficiency for all three compounds. Extraction tests at this upper level of moisture content showed removal efficiencies ≥70% for all the compounds and their ternary mixture, for 24 h of contact time, which is in contrast to the weeks and months, normally required for conventional ex situ remediation processes. A dynamic model characterizing the rate and extent of decontamination was also formulated, calibrated and validated with the experimental data. The proposed model, based on the simplified approach of "lumped parameters" for the mass transfer coefficients, provided very good predictions of the experimental data for the absorptive removal of contaminants from soil at different individual solute levels. Parameters evaluated from calibration by fitting of single compound data, have been successfully applied to predict mixture data, with differences between experimental and predicted data in all cases being ≤3%. Copyright © 2014 Elsevier Ltd. All rights reserved.

Is your lunch salad safe to eat? Occurrence of bacterial pathogens and potential for pathogen growth in pre-packed ready-to-eat mixed-ingredient salads.

PubMed

Söderqvist, Karin

2017-01-01

As part of a trend toward healthy convenience foods, ready-to-eat (RTE) mixed-ingredient salads have become popular products among consumers. A mixed-ingredient salad contains combinations of raw ( e.g . leafy vegetables and tomatoes) and processed ( e.g . chicken, salmon, ham, pasta and couscous) ingredients. Contamination of leafy vegetables can occur during any step in the production chain and, since there is no step that kills pathogens, a completely safe final product can never be guaranteed. Meat ingredients, for example poultry meat and ham, are generally heat-treated before preparation, but may be contaminated after this treatment, e.g . when diced or sliced. When several ingredients are mixed together, cross-contamination may occur. Preparation of mixed-ingredient salads requires human handling, which presents an additional risk of bacterial contamination. With high-protein ingredients, e.g . cooked meat, the mixed-ingredient salad represents an excellent substrate for bacterial growth. This article reviews current knowledge regarding human bacterial pathogen prevalence in mixed-ingredient salads and the potential for pathogen growth in this product during storage.

Is your lunch salad safe to eat? Occurrence of bacterial pathogens and potential for pathogen growth in pre-packed ready-to-eat mixed-ingredient salads

PubMed Central

Söderqvist, Karin

2017-01-01

ABSTRACT As part of a trend toward healthy convenience foods, ready-to-eat (RTE) mixed-ingredient salads have become popular products among consumers. A mixed-ingredient salad contains combinations of raw (e.g. leafy vegetables and tomatoes) and processed (e.g. chicken, salmon, ham, pasta and couscous) ingredients. Contamination of leafy vegetables can occur during any step in the production chain and, since there is no step that kills pathogens, a completely safe final product can never be guaranteed. Meat ingredients, for example poultry meat and ham, are generally heat-treated before preparation, but may be contaminated after this treatment, e.g. when diced or sliced. When several ingredients are mixed together, cross-contamination may occur. Preparation of mixed-ingredient salads requires human handling, which presents an additional risk of bacterial contamination. With high-protein ingredients, e.g. cooked meat, the mixed-ingredient salad represents an excellent substrate for bacterial growth. This article reviews current knowledge regarding human bacterial pathogen prevalence in mixed-ingredient salads and the potential for pathogen growth in this product during storage. PMID:29230273

Superfund Record of Decision (EPA Region 5): Midco I, Gary, IN. (First remedial action), (amendment), April 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The 4-acre Midco I site is an abandoned, industrial waste recycling, storage, and disposal facility in Gary, Indiana. The surrounding land use is mixed industrial, commercial, and residential. The Calumet Aquifer underlies the site and provides drinking water to wells within 1 mile of the site. The primary contaminants are VOCs, including TCE, toluene, and xylenes; metals, including chromium and lead; and inorganics. The amended remedial action for the ROD includes a reduction in the amount of soil to be treated to a minimum of 5,200 cubic yards because of the amendment to soil CALs and the determination that arsenicmore » may not be present above background levels at the site; and treating the contaminated soil onsite using with soil vapor extraction, followed by in-situ solidification/stabilization; and excavating and treating contaminated sediment from the surrounding wetlands.« less

Transfusions and kids: the deadly HIV link in Africa.

PubMed

1997-12-01

Contaminated blood transfusions are responsible for a large proportion of HIV infections, particularly among children, in developing countries. Little attention or money has been provided to control these easily preventable transmissions. According to the Centers for Disease Control and Prevention (CDC), basic remedies such as improving blood-screening and blood-banking practices, reducing the number of unnecessary transfusions, and treating malaria with different drugs could play a key role in reducing infection. The quality of blood-screening is often variable and inconsistent across a single country, and a study in Congo found that contaminated blood accounted for 42 percent of HIV infections in children older than one year. Blood transfusions are a common treatment in Africa, where they are used to treat malaria-related anemias. Malaria remains a major health threat in much of the world, and efforts to treat it more effectively will help reduce the number of HIV infections that result from contaminated blood sources.

The EDTA effect on phytoextraction of single and combined metals-contaminated soils using rainbow pink (Dianthus chinensis).

PubMed

Lai, Hung-Yu; Chen, Zueng-Sang

2005-08-01

Rainbow pink (Dianthus chinensis), a potential phytoextraction plant, can accumulate high concentrations of Cd from metal-contaminated soils. The soils used in this study were artificially added with different metals including (1) CK: original soil, (2) Cd-treated soil: 10 mg Cd kg(-1), (3) Zn-treated soil: 100 mg Zn kg(-1), (4) Pb-treated soil: 1000 mg Pb kg(-1), (5) Cd-Zn-treated soil: 10 mg Cd kg(-1) and 100 mg Zn kg(-1), (6) Cd-Pb-treated soil: 10 mg Cd kg(-1) and 1000 mg Pb kg(-1), (7) Zn-Pb-treated soil: 100 mg Zn kg(-1) and 1000 mg Pb kg(-1), and (8) Cd-Zn-Pb-treated soil: 10 mg Cd kg(-1), 100 mg Zn kg(-1), and 1000 mg Pb kg(-1). Three concentrations of 2Na-EDTA solutions (0 (control), 2, and 5 mmol kg(-1) soil) were added to the different metals-treated soils to study the influence of applied EDTA on single and combined metals-contaminated soils phytoextraction using rainbow pink. The results showed that the Cd, Zn, Pb, Fe, or Mn concentrations in different metals-treated soil solutions significantly increased after applying 5 mmol EDTA kg(-1) (p<0.05). The metal concentrations in different metals-treated soils extracted by deionized water also significantly increased after applying 5 mmol EDTA kg(-1) (p<0.05). Because of the high extraction capacity of both 0.005 M DTPA (pH 5.3) and 0.05 M EDTA (pH 7.0), applying EDTA did not significantly increase the Cd, Zn, or Pb concentration in both extracts for most of the treatments. Applying EDTA solutions can significantly increase the Cd and Pb concentrations in the shoots of rainbow pink (p<0.05). However, this was not statistically significant for Zn because of the low Zn concentration added into the contaminated soils. The results from this study indicate that applying 5 mmol EDTA kg(-1) can significantly increase the Cd, Zn, or Pb concentrations both in the soil solution or extracted using deionized water in single or combined metals-contaminated soils, thus increasing the accumulated metals concentrations in rainbow pink shoots. The proposed method worked especially well for Pb (p<0.05). The application of 2 mmol EDTA kg(-1) might too low to enhance the phytoextraction effect when used in silty clay soils.

Solar-chemical treatment of groundwater contaminated with petroleum at gas station sites: ex situ remediation using solar/TiO(2) photocatalysis and Solar Photo-Fenton.

PubMed

Cho, Ii-Hyoung; Kim, Young-Gyu; Yang, Jae-Kyu; Lee, Nae-Hyun; Lee, Seung-Mok

2006-01-01

Groundwater samples contaminated by BTEX (benzene, toluene, ethylbenzene, xylene isomers and TPHs (total petroleum hydrocarbons) were treated with advanced oxidation processes (AOPs), such as TiO(2) photocatalysis and Fe(2+)/H(2)O(2) exposed to solar light (37 degrees N and 128 degrees E) with an average intensity of 1.7 mW/cm(2) at 365 nm. These AOP processes showed feasibility in the treatment of groundwater contaminated with BTEX, TPH and TOC (Total Organic Carbon). Outdoor field tests showed that the degradation efficiency of each contaminant was higher in the Fe(2+)/H(2)O(2) system without solar light compared to the TiO(2)/solar light and H(2)O(2)/solar light systems. However, the TiO(2)/solar light and the Fe(2+)/H(2)O(2)/solar light systems showed significantly enhanced efficiencies in the degradation of BTEX, TPH and TOC with the additional use of H(2)O(2). Near complete degradation of BTEX and TPH was observed within 2 and 4 hrs, respectively, however, that of TOC was slower. Without pretreatment of the groundwater, fouling of the TiO(2), due to the ionic species present, was observed within 1 hr of operation, which resulted in the inhibition of further BTEX, TPH and TOC destruction. The degradation rate of n-alkanes with carbon numbers ranging from C10 to C15 was relatively greater than that of n-alknaes with carbon numbers ranging from C16 to C20. From this work, the AOP process (Fe(2+)/H(2)O(2)/solar light and TiO(2)/H(2)O(2)/solar light) illuminated with solar light was identified as an effective ex situ technique in the remediation of groundwater contaminated with petroleum.

Remediation System Evaluation, Selma Pressure Treating Superfund Site

EPA Pesticide Factsheets

The Selma Pressure Treating site is located 15 miles south of Fresno, adjacent to the city limits of Selma,California and has subsurface contamination from a former wood treating facility. The site occupiesapproximately 40 acres, including...

In Situ Thermal Treatment of Chlorinated Solvents: Fundamentals and Field Applications

EPA Pesticide Factsheets

This report contains information about the use of in situ thermal treatment technologies to treat chlorinated solvents in source zones containing free-phase contamination or high concentrations of contaminants.

Linking geological and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria.

PubMed

Plumlee, Geoffrey S; Durant, James T; Morman, Suzette A; Neri, Antonio; Wolf, Ruth E; Dooyema, Carrie A; Hageman, Philip L; Lowers, Heather A; Fernette, Gregory L; Meeker, Gregory P; Benzel, William M; Driscoll, Rhonda L; Berry, Cyrus J; Crock, James G; Goldstein, Harland L; Adams, Monique; Bartrem, Casey L; Tirima, Simba; Behbod, Behrooz; von Lindern, Ian; Brown, Mary Jean

2013-06-01

In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more. Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional toxicants of concern and populations at risk, and examine potential for similar lead poisoning globally. We applied diverse analytical methods to ore samples, soil and sweep samples from villages and family compounds, and plant foodstuff samples. Natural weathering of lead-rich gold ores before mining formed abundant, highly gastric-bioaccessible lead carbonates. The same fingerprint of lead minerals found in all sample types confirms that ore processing caused extreme contamination, with up to 185,000 ppm lead in soils/sweep samples and up to 145 ppm lead in plant foodstuffs. Incidental ingestion of soils via hand-to-mouth transmission and of dusts cleared from the respiratory tract is the dominant exposure pathway. Consumption of water and foodstuffs contaminated by the processing is likely lesser, but these are still significant exposure pathways. Although young children suffered the most immediate and severe consequences, results indicate that older children, adult workers, pregnant women, and breastfed infants are also at risk for lead poisoning. Mercury, arsenic, manganese, antimony, and crystalline silica exposures pose additional health threats. Results inform ongoing efforts in Nigeria to assess lead contamination and poisoning, treat victims, mitigate exposures, and remediate contamination. Ore deposit geology, pre-mining weathering, and burgeoning artisanal mining may combine to cause similar lead poisoning disasters elsewhere globally.

Linking Geological and Health Sciences to Assess Childhood Lead Poisoning from Artisanal Gold Mining in Nigeria

PubMed Central

Durant, James T.; Morman, Suzette A.; Neri, Antonio; Wolf, Ruth E.; Dooyema, Carrie A.; Hageman, Philip L.; Lowers, Heather A.; Fernette, Gregory L.; Meeker, Gregory P.; Benzel, William M.; Driscoll, Rhonda L.; Berry, Cyrus J.; Crock, James G.; Goldstein, Harland L.; Adams, Monique; Bartrem, Casey L.; Tirima, Simba; Behbod, Behrooz; von Lindern, Ian; Brown, Mary Jean

2013-01-01

Background: In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more. Objectives: Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional toxicants of concern and populations at risk, and examine potential for similar lead poisoning globally. Methods: We applied diverse analytical methods to ore samples, soil and sweep samples from villages and family compounds, and plant foodstuff samples. Results: Natural weathering of lead-rich gold ores before mining formed abundant, highly gastric-bioaccessible lead carbonates. The same fingerprint of lead minerals found in all sample types confirms that ore processing caused extreme contamination, with up to 185,000 ppm lead in soils/sweep samples and up to 145 ppm lead in plant foodstuffs. Incidental ingestion of soils via hand-to-mouth transmission and of dusts cleared from the respiratory tract is the dominant exposure pathway. Consumption of water and foodstuffs contaminated by the processing is likely lesser, but these are still significant exposure pathways. Although young children suffered the most immediate and severe consequences, results indicate that older children, adult workers, pregnant women, and breastfed infants are also at risk for lead poisoning. Mercury, arsenic, manganese, antimony, and crystalline silica exposures pose additional health threats. Conclusions: Results inform ongoing efforts in Nigeria to assess lead contamination and poisoning, treat victims, mitigate exposures, and remediate contamination. Ore deposit geology, pre-mining weathering, and burgeoning artisanal mining may combine to cause similar lead poisoning disasters elsewhere globally. PMID:23524139

Linking geology and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria

USGS Publications Warehouse

Plumlee, Geoffrey S.; Durant, James T.; Morman, Suzette A.; Neri, Antonio; Wolf, Ruth E.; Dooyema, Carrie A.; Hageman, Philip L.; Lowers, Heather; Fernette, Gregory L.; Meeker, Gregory P.; Benzel, William M.; Driscoll, Rhonda L.; Berry, Cyrus J.; Crock, James G.; Goldstein, Harland L.; Adams, Monique; Bartrem, Casey L.; Tirima, Simba; Behrooz, Behbod; von Lindern, Ian; Brown, Mary Jean

2013-01-01

Background: In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more. Objectives: Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional toxicants of concern and populations at risk, and examine potential for similar lead poisoning globally. Methods: We applied diverse analytical methods to ore samples, soil and sweep samples from villages and family compounds, and plant foodstuff samples. Results: Natural weathering of lead-rich gold ores before mining formed abundant, highly gastric-bioaccessible lead carbonates. The same fingerprint of lead minerals found in all sample types confirms that ore processing caused extreme contamination, with up to 185,000 ppm lead in soils/sweep samples and up to 145 ppm lead in plant foodstuffs. Incidental ingestion of soils via hand-to-mouth transmission and of dusts cleared from the respiratory tract is the dominant exposure pathway. Consumption of water and foodstuffs contaminated by the processing is likely lesser, but these are still significant exposure pathways. Although young children suffered the most immediate and severe consequences, results indicate that older children, adult workers, pregnant women, and breastfed infants are also at risk for lead poisoning. Mercury, arsenic, manganese, antimony, and crystalline silica exposures pose additional health threats. Conclusions: Results inform ongoing efforts in Nigeria to assess lead contamination and poisoning, treat victims, mitigate exposures, and remediate contamination. Ore deposit geology, pre-mining weathering, and burgeoning artisanal mining may combine to cause similar lead poisoning disasters elsewhere globally.

Growth determinations for unattached bacteria in a contaminated aquifer.

USGS Publications Warehouse

Harvey, R.W.; George, L.H.

1987-01-01

Growth rates of unattached bacteria in groundwater contaminated with treated sewage and collected at various distances from the source of contamination were estimated by using frequency of dividing cells and tritiated-thymidine uptake and compared with growth rates obtained with unsupplemented, closed-bottle incubations. Estimates of bacterial generation times [(In 2)/mu] along a 3-km-long transect in oxygen-depleted (0.1 to 0.7 mg of dissolved oxygen liter-1) groundwater ranged from 16 h at 0.26 km downgradient from an on-land, treated-sewage outfall to 139 h at 1.6 km and correlated with bacterial abundance (r2 = 0.88 at P less than 0.001). Partitioning of assimilated thymidine into nucleic acid generally decreased with distance from the contaminant source, and one population in heavily contaminated groundwater assimilated little thymidine during a 20-h incubation. Several assumptions commonly made when frequency of dividing cells and tritiated-thymidine uptake are used were not applicable to the groundwater samples.

Phytoremediation of a nitrogen-contaminated desert soil by native shrubs and microbial processes

DOE PAGES

Glenn, Edward P.; Jordan, Fiona; Waugh, W. Joseph

2016-02-24

Here, we combined phytoremediation and soil microbial nitrification and denitrification cycles to reduce nitrate and ammonium levels at a former uranium mill site near Monument Valley, Arizona. Ammonia used in uranium extraction was present throughout the soil profile. Sulfate,applied as sulfuric acid to solubilize uranium, was also present in the soil. These contaminants were leaching from a denuded area where a tailings pile had been removed and were migrating away from the site in groundwater. We planted the source area with two deep-rooted native shrubs, Atriplex cansescens and Sarcobatus vermiculatus, and irrigated transplants for 11 years at 20% the ratemore » of potential evapotranspiration to stimulate growth, then discontinued irrigation for 4 years. Over 15 years, total nitrogen levels dropped 82%, from 347 to 64 mg kg –1. Analysis of δ 15N supported our hypothesis that coupled microbial nitrification and denitrification processes were responsible for the loss of N. Soil sulfate levels changed little; however, evapotranspiration reduced sulfate leaching into the aquifer. For arid sites where traditional pump-and-treat methods are problematic, the Monument Valley data suggest that alternatives that incorporate native plants and rely on vadose zone biogeochemistry and hydrology could be a sustainable remediation for nitrogen contaminated soil.« less

Use of solar advanced oxidation processes for wastewater treatment: Follow-up on degradation products, acute toxicity, genotoxicity and estrogenicity.

PubMed

Brienza, M; Mahdi Ahmed, M; Escande, A; Plantard, G; Scrano, L; Chiron, S; Bufo, S A; Goetz, V

2016-04-01

Wastewater tertiary treatment by advanced oxidation processes is thought to produce a treated effluent with lower toxicity than the initial influent. Here we performed tertiary treatment of a secondary effluent collected from a Waste Water Treatment Plant via homogeneous (solar/HSO5(-)/Fe(2+)) and heterogeneous (solar/TiO2) solar advanced oxidation aiming at the assessment of their effectiveness in terms of contaminants' and toxicity abatement in a plain solar reactor. A total of 53 organic contaminants were qualitatively identified by liquid chromatography coupled to high-resolution mass spectrometry after solid phase extraction. Solar advanced oxidation totally or partially removed the major part of contaminants detected within 4.5 h. Standard toxicity tests were performed using Vibrio fischeri, Daphnia magna, Pseudokirchneriella subcapitata and Brachionus calyciflorus organisms to evaluate acute and chronic toxicity in the secondary or tertiary effluents, and the EC50% was calculated. Estrogenic and genotoxic tests were carried out in an attempt to obtain an even sharper evaluation of potential hazardous effects due to micropollutants or their degradation by-products in wastewater. Genotoxic effects were not detected in effluent before or after treatment. However, we observed relevant estrogenic activity due to the high sensitivity of the HELN ERα cell line. Copyright © 2016 Elsevier Ltd. All rights reserved.

Performance and mechanisms for the removal of phthalates and pharmaceuticals from aqueous solution by graphene-containing ceramic composite tubular membrane coupled with the simultaneous electrocoagulation and electrofiltration process.

PubMed

Yang, Gordon C C; Chen, Ying-Chun; Yang, Hao-Xuan; Yen, Chia-Heng

2016-07-01

In this study, commonly detected emerging contaminants (ECs) in water, including di-n-butyl phthalate (DnBP), di(2-ethylhexyl) phthalate (DEHP), cephalexin (CLX), sulfamethoxazole (SMX) and caffeine (CAF), were selected as the target contaminants. A lab-prepared graphene-containing ceramic composite tubular membrane (TGCCM) coupled with the simultaneous electrocoagulation and electrofiltration process (EC/EF) in crossflow filtration mode was used to remove target contaminants in model solution. Meanwhile, a comparison of the removal efficiency was made among various tubular composite membranes reported, including carbon fibers/carbon/alumina composite tubular membrane (TCCACM), titania/alumina composite tubular membrane (TTACM) and alumina tubular membrane (TAM). The results of this study showed that the removal efficiencies for DnBP and DEHP were 99%, whereas 32-97% for cephalexin (CLX), sulfamethoxazole (SMX) and caffeine (CAF). In this work the mechanisms involved in removing target ECs were proposed and their roles in removing various ECs were also discussed. Further, two actual municipal wastewaters were treated to evaluate the applicability of the aforementioned treatment technology (i.e., TGCCM coupled with EC/EF) to various aqueous solutions in the real world. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phytoremediation of a nitrogen-contaminated desert soil by native shrubs and microbial processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glenn, Edward P.; Jordan, Fiona; Waugh, W. Joseph

Here, we combined phytoremediation and soil microbial nitrification and denitrification cycles to reduce nitrate and ammonium levels at a former uranium mill site near Monument Valley, Arizona. Ammonia used in uranium extraction was present throughout the soil profile. Sulfate,applied as sulfuric acid to solubilize uranium, was also present in the soil. These contaminants were leaching from a denuded area where a tailings pile had been removed and were migrating away from the site in groundwater. We planted the source area with two deep-rooted native shrubs, Atriplex cansescens and Sarcobatus vermiculatus, and irrigated transplants for 11 years at 20% the ratemore » of potential evapotranspiration to stimulate growth, then discontinued irrigation for 4 years. Over 15 years, total nitrogen levels dropped 82%, from 347 to 64 mg kg –1. Analysis of δ 15N supported our hypothesis that coupled microbial nitrification and denitrification processes were responsible for the loss of N. Soil sulfate levels changed little; however, evapotranspiration reduced sulfate leaching into the aquifer. For arid sites where traditional pump-and-treat methods are problematic, the Monument Valley data suggest that alternatives that incorporate native plants and rely on vadose zone biogeochemistry and hydrology could be a sustainable remediation for nitrogen contaminated soil.« less

Waste wood as bioenergy feedstock. Climate change impacts and related emission uncertainties from waste wood based energy systems in the UK.

PubMed

Röder, Mirjam; Thornley, Patricia

2018-04-01

Considering the urgent need to shift to low carbon energy carriers, waste wood resources could provide an alternative energy feedstock and at the same time reduce emissions from landfill. This research examines the climate change impacts and related emission uncertainties of waste wood based energy. For this, different grades of waste wood and energy application have been investigated using lifecycle assessment. Sensitivity analysis has then been applied for supply chain processes and feedstock properties for the main emission contributing categories: transport, processing, pelletizing, urea resin fraction and related N 2 O formation. The results show, depending on the waste wood grade, the conversion option, scale and the related reference case, that emission reductions of up to 91% are possible for non-treated wood waste. Compared to this, energy from treated wood waste with low contamination can achieve up to 83% emission savings, similar to untreated waste wood pellets, but in some cases emissions from waste wood based energy can exceed the ones of the fossil fuel reference - in the worst case by 126%. Emission reductions from highly contaminated feedstocks are largest when replacing electricity from large-scale coal and landfill. The highest emission uncertainties are related to the wood's resin fraction and N 2 O formation during combustion and, pelletizing. Comparing wood processing with diesel and electricity powered equipment also generated high variations in the results, while emission variations related to transport are relatively small. Using treated waste wood as a bioenergy feedstock can be a valid option to reduce emissions from energy production but this is only realisable if coal and landfill gas are replaced. To achieve meaningful emission reduction in line with national and international climate change targets, pre-treatment of waste wood would be required to reduce components that form N 2 O during the energy conversion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Addressing the risk of bacterial contamination in platelets: a hospital economic perspective.

PubMed

Li, Justin W; Brecher, Mark E; Jacobson, Jessica L; Harm, Sarah K; Chen, Dorothy; El-Gamil, Audrey; Dobson, Al; Mintz, Paul D

2017-10-01

Bacterially contaminated platelets (PLTs) remain a serious risk. The Food and Drug Administration has issued draft guidance recommending hospitals implement secondary testing or transfuse PLTs that have been treated with pathogen reduction technology (PRT). The cost implications of these approaches are not well understood. We modeled incurred costs when hospitals acquire, process, and transfuse PLTs that are PRT treated with INTERCEPT (Cerus Corp.) or secondary tested with the PLT PGD Test (Verax Biomedical). Hospitals will spend $221.27 (30.0%) more per PRT-treated apheresis PLT unit administered compared to a Zika-tested apheresis PLT unit that is irradiated and PGD tested in hospital. This difference is reflected in PRT PLT units having: 1) a higher hospital purchase price ($100.00 additional charge compared to an untreated PLT); 2) lower therapeutic effectiveness than untreated PLTs among hematologic-oncologic patients, which contributes to additional transfusions ($96.05); or 3) fewer PLT storage days, which contributes to higher outdating cost from expired PLTs ($67.87). Only a small portion of the incremental costs for PRT-treated PLTs are offset by costs that may be avoided, including primary bacterial culture, secondary bacterial testing ($26.65), hospital irradiation ($8.50), Zika testing ($4.47), and other costs ($3.03). The significantly higher cost of PRT-treated PLTs over PGD-tested PLTs should interest stakeholders. For hospitals that outdate PLTs, savings associated with expiration extension to 7 days by adding PGD testing will likely be substantially greater than the cost of implementing PGD-testing. Our findings might usefully inform a hospital's decision to select a particular blood safety approach. © 2017 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

Treatment of urban river contaminated sediment with ex situ advanced oxidation processes: technical feasibility, environmental discharges and cost-performance analysis.

PubMed

Yan, Dickson Y S; Liu, Tongzhou; Lo, Irene M C

2015-01-01

The technical feasibility, environmental discharges and cost-performance of urban river contaminated sediment treatment with ex situ advanced oxidation processes were evaluated for the purpose of achieving an ideal treatment goal (for marine disposal) and a cost-performance treatment goal (for beneficially reusing as a filling material). Sediment samples were collected from a river located in southern China. To achieve the ideal treatment goal, sequential treatments (Fenton's reaction+activated persulphate oxidation) were carried out. One-step Fenton's reaction was applied to achieve the cost-performance treatment goal. The resulting effluent was treated and discharged, and sludge generated in wastewater treatment was characterized. The resources input throughout the treatment processes were recorded for cost estimation. After the treatment designed for achieving the ideal treatment goal, most pollutants fulfilled the treatment goal except Pb, Cd, Hg and Ag, probably because these four metals were present mainly in stable fractions of the sediment. The cost-performance treatment goal was achieved in view of low pollutant contents in the toxicity characteristic leaching procedure leachate of treated sediment. The cost for achieving the cost-performance treatment goal is much less than that for achieving the ideal treatment goal. The major cost difference is attributed to chemical cost. Stringent sediment treatment goals based on existing standards would lead to massive chemical use, complex treatment and hence huge cost. A simpler treatment with fewer chemicals is adequate for sediment beneficially reused as a filling material, and is economically more advantageous than handling sediment for marine disposal.

Identification of critical contaminants in wastewater effluent for managed aquifer recharge.

PubMed

Yuan, Jie; Van Dyke, Michele I; Huck, Peter M

2017-04-01

Managed aquifer recharge (MAR) using highly treated effluent from municipal wastewater treatment plants has been recognized as a promising strategy for indirect potable water reuse. Treated wastewater effluent can contain a number of residual contaminants that could have adverse effects on human health, and some jurisdictions have regulations in place to govern these. For those that do not, but where reuse may be under consideration, it is of crucial importance to develop a strategy for identifying priority contaminants, which can then be used to understand the water treatment technologies that might be required. In this study, a multi-criteria approach to identify critical contaminants in wastewater effluent for MAR was developed and applied using a case study site located in southern Ontario, Canada. An important aspect of this approach was the selection of representative compounds for each group of contaminants, based on potential for occurrence in wastewater and expected health or environmental impacts. Due to a lack of MAR regulations in Canada, the study first proposed potential recharge water quality targets. Predominant contaminants, potential additional contaminants, and potential emerging contaminants, which together comprise critical contaminants for MAR with reclaimed water, were then selected based on the case study wastewater effluent monitoring data and literature data. This paper proposes an approach for critical contaminant selection, which will be helpful to guide future implementation of MAR projects using wastewater treatment plant effluents. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quantitative microbial risk assessment of microbial source tracking markers in recreational water contaminated with fresh untreated and secondary treated sewage.

PubMed

Ahmed, Warish; Hamilton, Kerry A; Lobos, Aldo; Hughes, Bridie; Staley, Christopher; Sadowsky, Michael J; Harwood, Valerie J

2018-05-14

Microbial source tracking (MST) methods have provided the means to identify sewage contamination in recreational waters, but the risk associated with elevated levels of MST targets such as sewage-associated Bacteroides HF183 and other markers is uncertain. Quantitative microbial risk assessment (QMRA) modeling allows interpretation of MST data in the context of the risk of gastrointestinal (GI) illness caused by exposure to known reference pathogens. In this study, five sewage-associated, quantitative PCR (qPCR) MST markers [Bacteroides HF183 (HF183), Methanobrevibacter smithii nifH (nifH), human adenovirus (HAdV), human polyomavirus (HPyV) and pepper mild mottle virus (PMMoV)] were evaluated to determine at what concentration these nucleic acid markers reflected a significant health risk from exposure to fresh untreated or secondary treated sewage in beach water. The QMRA models were evaluated for a target probability of illness of 36 GI illnesses/1000 swimming events (i.e., risk benchmark 0.036) for the reference pathogens norovirus (NoV) and human adenovirus 40/41 (HAdV 40/41). Sewage markers at several dilutions exceeded the risk benchmark for reference pathogens NoV and HAdV 40/41. HF183 concentrations 3.22 × 10 3 (for both NoV and HAdV 40/41) gene copies (GC)/100 mL of water contaminated with fresh untreated sewage represented risk >0.036. Similarly, HF183 concentrations 3.66 × 10 3 (for NoV and HAdV 40/41) GC/100 mL of water contaminated with secondary treated sewage represented risk >0.036. HAdV concentration as low as 4.11 × 10 1 GC/100 mL of water represented risk >0.036 when water was contaminated with secondary treated sewage. Results of this study provide a valuable context for water quality managers to evaluate human health risks associated with contamination from fresh sewage. The approach described here may also be useful in the future for evaluating health risks from contamination with aged or treated sewage or feces from other animal sources as more data are made available. Copyright © 2018 Elsevier Ltd. All rights reserved.

Relating monolithic and granular leaching from contaminated soil treated with different cementitious binders.

PubMed

Kogbara, Reginald B; Al-Tabbaa, Abir; Stegemann, Julia A

2013-01-01

This work employed a clayey, silty, sandy gravel contaminated with a mixture of metals (Cd, Cu, Pb, Ni and Zn) and diesel. The contaminated soil was treated with 5 and 10% dosages of different cementitious binders. The binders include Portland cement, cement-fly ash, cement-slag and lime-slag mixtures. Monolithic leaching from the treated soils was evaluated over a 64-day period alongside granular leachability of 49- and 84-day old samples. Surface wash-off was the predominant leaching mechanism for monolithic samples. In this condition, with data from different binders and curing ages combined, granular leachability as a function of monolithic leaching generally followed degrees 4 and 6 polynomial functions. The only exception was for Cu, which followed the multistage dose-response model. The relationship between both leaching tests varied with the type of metal, curing age/residence time of monolithic samples in the leachant, and binder formulation. The results provide useful design information on the relationship between leachability of metals from monolithic forms of S/S treated soils and the ultimate leachability in the eventual breakdown of the stabilized/solidified soil.

Membrane bioreactors for the removal of anionic micropollutants from drinking water.

PubMed

Crespo, João G; Velizarov, Svetlozar; Reis, Maria A

2004-10-01

Biological treatment processes allow for the effective elimination of anionic micropollutants from drinking water. However, special technologies have to be implemented to eliminate the target pollutants without changing water quality, either by adding new pollutants or removing essential water components. Some innovative technologies that combine the use of membranes with the biological degradation of ionic micropollutants in order to minimize the secondary contamination of treated water include pressure-driven membrane bioreactors, gas-transfer membrane bioreactors and ion exchange membrane bioreactors.

IMPROVED PROCESS OF PLUTONIUM CARRIER PRECIPITATION

DOEpatents

Faris, B.F.

1959-06-30

This patent relates to an improvement in the bismuth phosphate process for separating and recovering plutonium from neutron irradiated uranium, resulting in improved decontamination even without the use of scavenging precipitates in the by-product precipitation step and subsequently more complete recovery of the plutonium in the product precipitation step. This improvement is achieved by addition of fluomolybdic acid, or a water soluble fluomolybdate, such as the ammonium, sodium, or potassium salt thereof, to the aqueous nitric acid solution containing tetravalent plutonium ions and contaminating fission products, so as to establish a fluomolybdate ion concentration of about 0.05 M. The solution is then treated to form the bismuth phosphate plutonium carrying precipitate.

In situ removal of contamination from soil

DOEpatents

Lindgren, E.R.; Brady, P.V.

1997-10-14

A process of remediation of cationic heavy metal contamination from soil utilizes gas phase manipulation to inhibit biodegradation of a chelating agent that is used in an electrokinesis process to remove the contamination. The process also uses further gas phase manipulation to stimulate biodegradation of the chelating agent after the contamination has been removed. The process ensures that the chelating agent is not attacked by bioorganisms in the soil prior to removal of the contamination, and that the chelating agent does not remain as a new contaminant after the process is completed. 5 figs.

Using slow-release permanganate candles to remediate PAH-contaminated water.

PubMed

Rauscher, Lindy; Sakulthaew, Chainarong; Comfort, Steve

2012-11-30

Surface waters impacted by urban runoff in metropolitan areas are becoming increasingly contaminated with polycyclic aromatic hydrocarbons (PAHs). Slow-release oxidant candles (paraffin-KMnO(4)) are a relatively new technology being used to treat contaminated groundwater and could potentially be used to treat urban runoff. Given that these candles only release permanganate when submerged, the ephemeral nature of runoff events would influence when the permanganate is released for treating PAHs. Our objective was to determine if slow-release permanganate candles could be used to degrade and mineralize PAHs. Batch experiments quantified PAH degradation rates in the presence of the oxidant candles. Results showed most of the 16 PAHs tested were degraded within 2-4 h. Using (14)C-labled phenanthrene and benzo(a)pyrene, we demonstrated that the wax matrix of the candle initially adsorbs the PAH, but then releases the PAH back into solution as transformed, more water soluble products. While permanganate was unable to mineralize the PAHs (i.e., convert to CO(2)), we found that the permanganate-treated PAHs were much more biodegradable in soil microcosms. To test the concept of using candles to treat PAHs in multiple runoff events, we used a flow-through system where urban runoff water was pumped over a miniature candle in repetitive wet-dry, 24-h cycles. Results showed that the candle was robust in removing PAHs by repeatedly releasing permanganate and degrading the PAHs. These results provide proof-of-concept that permanganate candles could potentially provide a low-cost, low-maintenance approach to remediating PAH-contaminated water. Copyright © 2012 Elsevier B.V. All rights reserved.

Online sorting of recovered wood waste by automated XRF-technology: part II. Sorting efficiencies.

PubMed

Hasan, A Rasem; Solo-Gabriele, Helena; Townsend, Timothy

2011-04-01

Sorting of waste wood is an important process practiced at recycling facilities in order to detect and divert contaminants from recycled wood products. Contaminants of concern include arsenic, chromium and copper found in chemically preserved wood. The objective of this research was to evaluate the sorting efficiencies of both treated and untreated parts of the wood waste stream, and metal (As, Cr and Cu) mass recoveries by the use of automated X-ray fluorescence (XRF) systems. A full-scale system was used for experimentation. This unit consisted of an XRF-detection chamber mounted on the top of a conveyor and a pneumatic slide-way diverter which sorted wood into presumed treated and presumed untreated piles. A randomized block design was used to evaluate the operational conveyance parameters of the system, including wood feed rate and conveyor belt speed. Results indicated that online sorting efficiencies of waste wood by XRF technology were high based on number and weight of pieces (70-87% and 75-92% for treated wood and 66-97% and 68-96% for untreated wood, respectively). These sorting efficiencies achieved mass recovery for metals of 81-99% for As, 75-95% for Cu and 82-99% of Cr. The incorrect sorting of wood was attributed almost equally to deficiencies in the detection and conveyance/diversion systems. Even with its deficiencies, the system was capable of producing a recyclable portion that met residential soil quality levels established for Florida, for an infeed that contained 5% of treated wood. Copyright © 2010 Elsevier Ltd. All rights reserved.

GRACE BIOREMEDIATION TECHNOLOGIES - DARAMEND™ BIOREMEDIATION TECHNOLOGY. INNOVATIVE TECHNOLOGY EVALUATION REPORT

EPA Science Inventory

Grace Dearborn's DARAMEND™ Bioremediation Technology was developed to treat soils/sediment contaminated with organic contaminants using solid-phase organic amendments. The amendments increase the soil’s ability to supply biologically available water/nutrients to micro...

SITE TECHNOLOGY CAPSULE: GRACE DEARBORN INC.'S DARAMEND BIOREMEDIATION TECHNOLOGY

EPA Science Inventory

Grace Dearborn's DARAMEND Bioremediation Technology was developed to treat soils/sediment contaminated with organic contaminants using solid-phase organic amendments. The amendments increase the soil's ability to supply biologically available water/nutrients to microorganisms and...

Screening ornamentals for their potential as As Accumulator Plants

USDA-ARS?s Scientific Manuscript database

Arsenic-based pesticides, herbicides and insecticides are used in horticultural operations resulting in soil contamination around greenhouse structures. Phytoremediation and phytostabilization are two techniques for treating arsenic (As) contaminated soil. Several ornamental plant species, Iris (Ir...

Permeable Reactive Zones for Groundwater Remediation

EPA Science Inventory

The presentation will cover aspects of the application of permeable reactive zones to treat contaminated ground water. Specific field studies will be discussed covering both granular iron-based and organic carbon-based reactive barriers. Specific contaminants addressed include:...

PCB in the environment: bio-based processes for soil decontamination and management of waste from the industrial production of Pleurotus ostreatus.

PubMed

Siracusa, Giovanna; Becarelli, Simone; Lorenzi, Roberto; Gentini, Alessandro; Di Gregorio, Simona

2017-10-25

Polychlorinated biphenyls (PCBs) are hazardous soil contaminants for which a bio-based technology for their recovery is essential. The objective of this study was to validate the exploitation of spent mushroom substrate (SMS), a low or null cost organic waste derived from the industrial production of P. ostreatus, as bulking agent in a dynamic biopile pilot plant. The SMS shows potential oxidative capacity towards recalcitrant compounds. The aim was consistent with the design of a process of oxidation of highly chlorinated PCBs, which is independent from their reductive dehalogenation. Feasibility was verified at a mesocosm scale and validated at pilot scale in a dynamic biopile pilot plant treating ten tons of a historically contaminated soil (9.28±0.08mg PCB/kg soil dry weight). Mixing of the SMS with the soil was required for the depletion of the contaminants. At the pilot scale, after eight months of incubation, 94.1% depletion was recorded. A positive correlation between Actinobacteria and Firmicutes active metabolism, soil laccase activity and PCB removal was observed. The SMS was found to be exploitable as a versatile low cost organic substrate capable of activating processes for the oxidation of highly chlorinated PCBs. Moreover, its exploitation as bulking agent in biopiles is a valuable management strategy for the re-utilisation of an organic waste deriving from the industrial cultivation of edible mushrooms. Copyright © 2017 Elsevier B.V. All rights reserved.

An overview of dissolved organic carbon in groundwater and implications for drinking water safety

NASA Astrophysics Data System (ADS)

Regan, S.; Hynds, P.; Flynn, R.

2017-06-01

Dissolved organic carbon (DOC) is composed of a diverse array of compounds, predominantly humic substances, and is a near ubiquitous component of natural groundwater, notwithstanding climatic extremes such as arid and hyper-arid settings. Despite being a frequently measured parameter of groundwater quality, the complexity of DOC composition and reaction behaviour means that links between concentration and human health risk are difficult to quantify and few examples are reported in the literature. Measured concentrations from natural/unpolluted groundwater are typically below 4 mg C/l, whilst concentrations above these levels generally indicate anthropogenic influences and/or contamination issues and can potentially compromise water safety. Treatment processes are effective at reducing DOC concentrations, but refractory humic substance reaction with chlorine during the disinfection process produces suspected carcinogenic disinfectant by-products (DBPs). However, despite engineered artificial recharge systems being commonly used to remove DOC from recycled treated wastewaters, little research has been conducted on the presence of DBPs in potable groundwater systems. In recent years, the capacity to measure the influence of organic matter on colloidal contaminants and its influence on the mobility of pathogenic microorganisms has aided understanding of transport processes in aquifers. Additionally, advances in polymerase chain reaction techniques used for the detection, identification, and quantification of waterborne pathogens, provide a method to confidently investigate the behaviour of DOC and its effect on contaminant transfer in aquifers. This paper provides a summary of DOC occurrence in groundwater bodies and associated issues capable of indirectly affecting human health.

Sanitization of contaminated footwear from onychomycosis patients using ozone gas: a novel adjunct therapy for treating onychomycosis and tinea pedis?

PubMed

Gupta, Aditya K; Brintnell, William C

2013-01-01

Ozone gas possesses antimicrobial properties against bacteria, viruses, and yeasts. Previously, we demonstrated the efficacy of ozone in killing ATCC strains of the dermatophyte fungi Trichophyton rubrum and Trichophyton mentagrophytes. To test the efficacy of ozone gas in sanitizing onychomycosis patient footwear contaminated with fungal material as a means of minimizing the risk of reinfection. Swabs of footwear from onychomycosis patients were cultured prior to and after ozone exposure to test the ability of ozone to sanitize these items. We identified contamination of footwear from most onychomycosis patients, a potential source of reinfection in these individuals. Furthermore, ozone gas was effective in sanitizing contaminated footwear. Ozone gas is effective in sanitizing footwear and represents a novel adjunct therapy to be used in conjunction with antifungal medications and/or devices to better treat onychomycosis and tinea pedis patients in both the short and the long term.

Electrokinetic remediation of plutonium-contaminated nuclear site wastes: results from a pilot-scale on-site trial.

PubMed

Agnew, Kieran; Cundy, Andrew B; Hopkinson, Laurence; Croudace, Ian W; Warwick, Phillip E; Purdie, Philip

2011-02-28

This paper examines the field-scale application of a novel low-energy electrokinetic technique for the remediation of plutonium-contaminated nuclear site soils, using soil wastes from the Atomic Weapons Establishment (AWE) Aldermaston site, Berkshire, UK as a test medium. Soils and sediments with varying composition, contaminated with Pu through historical site operations, were electrokinetically treated at laboratory-scale with and without various soil pre-conditioning agents. Results from these bench-scale trials were used to inform a larger on-site remediation trial, using an adapted containment pack with battery power supply. 2.4 m(3) (ca. 4t onnes) of Pu-contaminated soil was treated for 60 days at a power consumption of 33 kWh/m(3), and then destructively sampled. Radiochemical data indicate mobilisation of Pu in the treated soil, and migration (probably as a negatively charged Pu-citrate complex) towards the anodic compartment of the treatment cell. Soil in the cathodic zone of the treatment unit was remediated to a level below free-release disposal thresholds (1.7 Bq/g, or <0.4 Bq/g above background activities). The data show the potential of this method as a low-cost, on-site tool for remediation of radioactively contaminated soils and wastes which can be operated remotely on working sites, with minimal disruption to site infrastructure or operations. Copyright © 2010 Elsevier B.V. All rights reserved.

Monticello Mill Tailings Site, Operable Unit lll, Annual Groundwater Report, May 2015 Through April 2016

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Jason; Smith, Fred

This report provides the annual analysis of water quality restoration progress, cumulative through April 2016, for Operable Unit (OU) III, surface water and groundwater, of the U.S. Department of Energy (DOE) Office of Legacy Management (LM) Monticello Mill Tailings Site (MMTS). The MMTS is a Comprehensive Environmental Response, Compensation, and Liability Act National Priorities List site located in and near the city of Monticello, San Juan County, Utah. MMTS comprises the 110-acre site of a former uranium- and vanadium-ore-processing mill (mill site) and 1700 acres of surrounding private and municipal property. Milling operations generated 2.5 million cubic yards of wastemore » (tailings) from 1942 to 1960. The tailings were impounded at four locations on the mill site. Inorganic constituents in the tailings drained from the impoundments to contaminate local surface water (Montezuma Creek) and groundwater in the underlying alluvial aquifer. Mill tailings dispersed by wind and water also contaminated properties surrounding and downstream of the mill site. Remedial actions to remove and isolate radiologically contaminated soil, sediment, and debris from the former mill site, Operable Unit I (OU I), and surrounding properties (OU II) were completed in 1999 with the encapsulation of the wastes in an engineered repository located on DOE property 1 mile south of the former mill site. This effectively removed the primary source of groundwater contamination; however, contamination of groundwater and surface water remains within OU III at levels that exceed water quality protection standards. Uranium is the primary contaminant of concern (COC). LM implemented monitored natural attenuation with institutional controls as the OU III remedy in 2004. Because groundwater restoration proceeded more slowly than expected and did not meet performance criteria established in the OU III Record of Decision (June 2004), LM implemented a contingency action in 2009 by an Explanation of Significant Difference to include a pump-and­ treat system using a single extraction well and treatment by zero-valent iron (ex situ treatment system). The contingency action was optimized in 2015 with the installation of8 extraction wells and 16 monitoring wells in a focused area of the aquifer, the area of attainment (AOA). Contaminated water is treated by solar evaporation at an existing facility at the LM repository.« less

Impact assessment of treated wastewater on water quality of the receiver using the Wilcoxon test

NASA Astrophysics Data System (ADS)

Ofman, Piotr; Puchlik, Monika; Simson, Grzegorz; Krasowska, Małgorzata; Struk-Sokołowska, Joanna

2017-11-01

Wastewater treatment is a process which aims to reduce the concentration of pollutants in wastewater to the level allowed by current regulations. This is to protect the receivers which typically are rivers, streams, lakes. Examination of the quality of treated wastewater allows for quick elimination of possible negative effects, and the study of water receiver prevents from excessive contamination. The paper presents the results of selected physical and chemical parameters of treated wastewater from the largest on the region in north-eastern Poland city of Bialystok municipal wastewater treatment and Biała River, the receiver. The samples for research were taken 3-4 a month in 2015 from two points: before and after discharge. The impact of the wastewater treatment plant on the quality of the receiver waters was studied by using non-parametric Wilcoxon test. This test determined whether the analyzed indicators varied significantly depending on different sampling points of the river, above and below place of discharge of treated wastewater. These results prove that the treated wastewater does not affect the water quality in the Biała River.

Removal of toluene in a vapor-phase bioreactor containing a strain of the dimorphic black yeast Exophiala lecanii-corni.

PubMed

Woertz, J R; Kinney, K A; McIntosh, N D; Szaniszlo, P J

2001-12-05

Stricter regulations on volatile organic compounds and hazardous air pollutants have increased the demand for abatement technologies. Biofiltration, a process in which contaminated air is passed through a biologically active bed, can be used to remove these pollutants from air streams. In this study, a fungal vapor-phase bioreactor containing a strain of the dimorphic black yeast, Exophiala lecanii-corni, was used to treat a gas stream contaminated with toluene. The maximum toluene elimination capacity in short-term tests was 270 g m(-3) h(-1), which is 2 to 7 times greater than the toluene elimination capacities typically reported for bacterial systems. The fungal bioreactor also maintained toluene removal efficiencies of greater than 95% throughout the 175-day study. Harsh operating conditions such as low moisture content, acidic biofilms, and nitrogen limitation did not adversely affect performance. The fungal bioreactor also rapidly reestablished high toluene removal efficiencies after an 8-day shutdown period. These results indicate that fungal bioreactors may be an effective alternative to conventional abatement technologies for treating high concentrations of pollutants in waste gas streams. Copyright 2001 John Wiley & Sons, Inc.

Inactivation of microorganisms in apple juice using an ultraviolet silica-fiber optical device.

PubMed

Lu, Gang; Li, Chaolin; Liu, Peng; Cui, Haibo; Xia, Yong; Wang, Jianfeng

2010-09-02

Most juices are opaque to ultraviolet (UV) due to the high-suspended solids in them and therefore the conventional UV treatment, generally used for water treatment, cannot be used for treating juices. In order to achieve a high germicidal efficiency of UV processing, an optical device with silica optical fibers for UV light delivery was designed. Its suitability for application could be shown in experiments with Escherichia coli, Lactobacillus brevis, Saccharomyces cerevisiae and naturally contaminating microorganisms as test microorganisms. The thin-film thickness for treating apple juice was optimized. At 2.0-mm film thickness, E. coli and L. brevis were reduced by up to 6 log orders with the UV dose of 23.7 m J/cm(2) and the optical-fiber distribution density of 15 fibers/cm(2), while only about 4-log reduction of S. cerevisiae was achieved under the same condition. Naturally contaminating lactic acid bacteria, Enterobacteriaceae and yeasts and moulds in freshly extracted apple juice were reduced to below 10 CFU/ml. These results indicate that this optical device could be used to improve microbial safety and extend shelf-life of apple juice. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Extraction of Profile Information from Cloud Contaminated Radiances. Appendixes 2

NASA Technical Reports Server (NTRS)

Smith, W. L.; Zhou, D. K.; Huang, H.-L.; Li, Jun; Liu, X.; Larar, A. M.

2003-01-01

Clouds act to reduce the signal level and may produce noise dependence on the complexity of the cloud properties and the manner in which they are treated in the profile retrieval process. There are essentially three ways to extract profile information from cloud contaminated radiances: (1) cloud-clearing using spatially adjacent cloud contaminated radiance measurements, (2) retrieval based upon the assumption of opaque cloud conditions, and (3) retrieval or radiance assimilation using a physically correct cloud radiative transfer model which accounts for the absorption and scattering of the radiance observed. Cloud clearing extracts the radiance arising from the clear air portion of partly clouded fields of view permitting soundings to the surface or the assimilation of radiances as in the clear field of view case. However, the accuracy of the clear air radiance signal depends upon the cloud height and optical property uniformity across the two fields of view used in the cloud clearing process. The assumption of opaque clouds within the field of view permits relatively accurate profiles to be retrieved down to near cloud top levels, the accuracy near the cloud top level being dependent upon the actual microphysical properties of the cloud. The use of a physically correct cloud radiative transfer model enables accurate retrievals down to cloud top levels and below semi-transparent cloud layers (e.g., cirrus). It should also be possible to assimilate cloudy radiances directly into the model given a physically correct cloud radiative transfer model using geometric and microphysical cloud parameters retrieved from the radiance spectra as initial cloud variables in the radiance assimilation process. This presentation reviews the above three ways to extract profile information from cloud contaminated radiances. NPOESS Airborne Sounder Testbed-Interferometer radiance spectra and Aqua satellite AIRS radiance spectra are used to illustrate how cloudy radiances can be used in the profile retrieval process.

Designer carbon nanotubes for contaminant removal in water and wastewater: A critical review.

PubMed

Sarkar, Binoy; Mandal, Sanchita; Tsang, Yiu Fai; Kumar, Pawan; Kim, Ki-Hyun; Ok, Yong Sik

2018-01-15

The search for effective materials for environmental cleanup is a scientific and technological issue of paramount importance. Among various materials, carbon nanotubes (CNTs) possess unique physicochemical, electrical, and mechanical properties that make them suitable for potential applications as environmental adsorbents, sensors, membranes, and catalysts. Depending on the intended application and the chemical nature of the target contaminants, CNTs can be designed through specific functionalization or modification processes. Designer CNTs can remarkably enhance contaminant removal efficiency and facilitate nanomaterial recovery and regeneration. An increasing number of CNT-based materials have been used to treat diverse organic, inorganic, and biological contaminants. These success stories demonstrate their strong potential in practical applications, including wastewater purification and desalination. However, CNT-based technologies have not been broadly accepted for commercial use due to their prohibitive cost and the complex interactions of CNTs with other abiotic and biotic environmental components. This paper presents a critical review of the existing literature on the interaction of various contaminants with CNTs in water and soil environments. The preparation methods of various designer CNTs (surface functionalized and/or modified) and the functional relationships between their physicochemical characteristics and environmental uses are discussed. This review will also help to identify the research gaps that must be addressed for enhancing the commercial acceptance of CNTs in the environmental remediation industry. Copyright © 2017 Elsevier B.V. All rights reserved.

Stabilization of As-, Pb-, and Cu-contaminated soil using calcined oyster shells and steel slag.

PubMed

Moon, Deok Hyun; Wazne, Mahmoud; Cheong, Kyung Hoon; Chang, Yoon-Young; Baek, Kitae; Ok, Yong Sik; Park, Jeong-Hun

2015-07-01

In this study, As-, Pb-, and Cu-contaminated soil was stabilized using calcined oyster shells (COS) and steel slag (SS). The As-contaminated soil was obtained from a timber mill site where chromate copper arsenate (CCA) was used as a preservative. On the other hand, Pb- and Cu-contaminated soil was obtained from a firing range. These two soils were thoroughly mixed to represent As-, Pb-, and Cu-contaminated soil. Calcined oyster shells were obtained by treating waste oyster shells at a high temperature using the calcination process. The effectiveness of stabilization was evaluated by 1-N HCl extraction for As and 0.1-N HCl extraction for Pb and Cu. The treatment results showed that As, Pb, and Cu leachability were significantly reduced upon the combination treatment of COS and SS. The sole treatment of SS (10 wt%) did not show effective stabilization. However, the combination treatment of COS and SS showed a significant reduction in As, Pb, and Cu leachability. The best stabilization results were obtained from the combination treatment of 15 wt% COS and 10 wt% SS. The SEM-EDX results suggested that the effective stabilization of As was most probably achieved by the formation of Ca-As and Fe-As precipitates. In the case of Pb and Cu, stabilization was most probably associated with the formation of pozzolanic reaction products such as CSHs and CAHs.

Contamination control in hybrid microelectronic modules. Identification of critical process and contaminants, part 1

NASA Technical Reports Server (NTRS)

Himmel, R. P.

1975-01-01

Hybrid processes, handling procedures, and materials were examined to identify the critical process steps in which contamination is most likely to occur, to identify the particular contaminants associated with these critical steps, and to propose method for the control of these contaminants.

Groundwater Contamination: DOD Uses and Develops a Range of Remediation Technologies to Clean Up Military Sites

DTIC Science & Technology

2005-06-01

relative cost -effectiveness of a technology for a given site. DOD has identified a number of contaminants of concern at its facilities, each of...to contain or eliminate hazardous contaminants in groundwater. However, the long cleanup times and high costs of using pump-and- treat technologies...environment. DOD estimates that cleanup of its contaminated sites will cost billions of dollars and may take decades to complete because of the

Effect of clay minerals and nanoparticles on chromium fractionation in soil contaminated with leather factory waste.

PubMed

Taghipour, Marzieh; Jalali, Mohsen

2015-10-30

This study was conducted to investigate the effect of time, clay minerals and nanoparticles (NPs) on chromium (Cr) fractionation in a soil contaminated with leather factory waste (LFW). Soil was mixed with LFW, then, the contaminated soils were treated with clay minerals (bentonite and zeolite) and nanoparticles (MgO, TiO2 and ZnO) at 5% and 1%, respectively. The samples were incubated for 15-180 days at 25 °C and constant moisture. After incubation, Cr in control and treated soils was fractionated by the sequential extraction procedure. The distribution of various Cr fractions in control soil indicated that the greatest amounts of Cr were found in the residual fraction (RES) followed by the carbonate (CAR), organic matter (OM) and exchangeable (EXC) fractions. The addition of LFW in soils increased Cr concentration in all fractions. The higher proportion of EXC fraction in the soil treated with LFW indicates its higher potential of leaching and runoff transport. In all treated soils, the RES fraction was increased, while EXC and OM fractions were decreased during incubation. The results indicated that NPs are effective adsorbent for the removal of Cr ions from LFW treated soil, and they could be useful in reducing their environment risk. Copyright © 2015 Elsevier B.V. All rights reserved.

PLUTONIUM PURIFICATION PROCESS EMPLOYING THORIUM PYROPHOSPHATE CARRIER

DOEpatents

King, E.L.

1959-04-28

The separation and purification of plutonium from the radioactive elements of lower atomic weight is described. The process of this invention comprises forming a 0.5 to 2 M aqueous acidffc solution containing plutonium fons in the tetravalent state and elements with which it is normally contaminated in neutron irradiated uranium, treating the solution with a double thorium compound and a soluble pyrophosphate compound (Na/sub 4/P/sub 2/O/sub 7/) whereby a carrier precipitate of thorium A method is presented of reducing neptunium and - trite is advantageous since it destroys any hydrazine f so that they can be removed from solutions in which they are contained is described. In the carrier precipitation process for the separation of plutonium from uranium and fission products including zirconium and columbium, the precipitated blsmuth phosphate carries some zirconium, columbium, and uranium impurities. According to the invention such impurities can be complexed and removed by dissolving the contaminated carrier precipitate in 10M nitric acid, followed by addition of fluosilicic acid to about 1M, diluting the solution to about 1M in nitric acid, and then adding phosphoric acid to re-precipitate bismuth phosphate carrying plutonium.

Assessment of nanofiltration and reverse osmosis potentialities to recover metals, sulfuric acid, and recycled water from acid gold mining effluent.

PubMed

Ricci, Bárbara C; Ferreira, Carolina D; Marques, Larissa S; Martins, Sofia S; Amaral, Míriam C S

This work assessed the potential of nanofiltration (NF) and reverse osmosis (RO) to treat acid streams contaminated with metals, such as effluent from the pressure oxidation process (POX) used in refractory gold ore processing. NF and RO were evaluated in terms of rejections of sulfuric acid and metals. Regarding NF, high sulfuric acid permeation (∼100%), was observed, while metals were retained with high efficiencies (∼90%), whereas RO led to high acid rejections (<88%) when conducted in pH values higher than 1. Thus, sequential use of NF and RO was proved to be a promising treatment for sulfuric acid solutions contaminated by metals, such as POX effluent. In this context, a purified acid stream could be recovered in NF permeate, which could be further concentrated in RO. Recovered acid stream could be reused in the gold ore processing or commercialized. A metal-enriched stream could be also recovered in NF retentate and transferred to a subsequent metal recovery stage. In addition, considering the high acid rejection obtained through the proposed system, RO permeate could be used as recycling water.

BIOREMEDIATION OF OIL-CONTAMINATED FINE SEDIMENTS.

EPA Science Inventory

Bioremediation of oil contamination has been shown to be effective for cobble and sandy shorelines. To assess the operational limitations of this technology, this project studied its potential to treat buried oil in fine sediments. The effectiveness of bioremediation by nutrient ...

DEMONSTRATION BULLETIN: FUNGAL TREATMENT BULLETIN

EPA Science Inventory

Fungal treatment technology uses white rot fungi (lignin degrading fungi) to treat organic contaminated soils in situ. Organic materials inoculated with the fungi are mechanically mixed into the contaminated soil. Using enzymes normally produced for wood degradation as well as ot...

TREATMENT STUDIES OF CCL CONTAMINANTS

EPA Science Inventory

Bench-scale screening-level treatment data are presented for compounds listed in the Contaminant Candidate List (CCL). All of the CCl compounds are predicted to be economically removed by either activated carbon or air stripping technologies. To complete the screening-level treat...

ENGINEERING BULLETIN: IN SITU BIODEGRADATION TREATMENT

EPA Science Inventory

In situ biodegradation may be used to treat low-to-intermediate concentrations of organic contaminants in place without disturbing or displacing the contaminated media. Although this technology has been used to degrade a limited number of inorganics, specifically cyanide and nitr...

Biosurfactant technology for remediation of cadmium and lead contaminated soils.

PubMed

Juwarkar, Asha A; Nair, Anupa; Dubey, Kirti V; Singh, S K; Devotta, Sukumar

2007-08-01

This research focuses on column experiments conducted to evaluate the potential of environmentally compatible rhamnolipid biosurfactant produced by Pseudomonas aeruginosa strain BS2 to remove heavy metals (Cd and Pb) from artificially contaminated soil. Results have shown that di-rhamnolipid removes not only the leachable or available fraction of Cd and Pb but also the bound metals as compared to tap water which removed the mobile fraction only. Washing of contaminated soil with tap water revealed that approximately 2.7% of Cd and 9.8% of Pb in contaminated soil was in freely available or weakly bound forms whereas washing with rhamnolipid removed 92% of Cd and 88% of Pb after 36 h of leaching. This indicated that di-rhamnolipid selectively favours mobilization of metals in the order of Cd>Pb. Biosurfactant specificity observed towards specific metal will help in preferential elution of specific contaminant using di-rhamnolipid. It was further observed that pH of the leachates collected from heavy metal contaminated soil column treated with di-rhamnolipid solution was low (6.60-6.78) as compared to that of leachates from heavy metal contaminated soil column treated with tap water (pH 6.90-7.25), which showed high dissolution of metal species from the contaminated soil and effective leaching of metals with treatment with biosurfactant. The microbial population of the contaminated soil was increased after removal of metals by biosurfactant indicating the decrease of toxicity of metals to soil microflora. This study shows that biosurfactant technology can be an effective and nondestructive method for bioremediation of cadmium and lead contaminated soil.

2009 EVALUATION OF TRITIUM REMOVAL AND MITIGATION TECHNOLOGIES FOR WASTEWATER TREATMENT

DOE Office of Scientific and Technical Information (OSTI.GOV)

LUECK KJ; GENESSE DJ; STEGEN GE

2009-02-26

Since 1995, a state-approved land disposal site (SALDS) has received tritium contaminated effluents from the Hanford Site Effluent Treatment Facility (ETF). Tritium in this effluent is mitigated by storage in slow moving groundwater to allow extended time for decay before the water reaches the site boundary. By this method, tritium in the SALDS is isolated from the general environment and human contact until it has decayed to acceptable levels. This report contains the 2009 update evaluation of alternative tritium mitigation techniques to control tritium in liquid effluents and groundwater at the Hanford site. A thorough literature review was completed andmore » updated information is provided on state-of-the-art technologies for control of tritium in wastewaters. This report was prepared to satisfy the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-026-07B (Ecology, EPA, and DOE 2007). Tritium separation and isolation technologies are evaluated periodically to determine their feasibility for implementation to control Hanford site liquid effluents and groundwaters to meet the Us. Code of Federal Regulations (CFR), Title 40 CFR 141.16, drinking water maximum contaminant level (MCL) for tritium of 20,000 pOll and/or DOE Order 5400.5 as low as reasonably achievable (ALARA) policy. Since the 2004 evaluation, there have been a number of developments related to tritium separation and control with potential application in mitigating tritium contaminated wastewater. These are primarily focused in the areas of: (1) tritium recycling at a commercial facility in Cardiff, UK using integrated tritium separation technologies (water distillation, palladium membrane reactor, liquid phase catalytic exchange, thermal diffusion), (2) development and demonstration of Combined Electrolysis Catalytic Exchange (CECE) using hydrogen/water exchange to separate tritium from water, (3) evaporation of tritium contaminated water for dispersion in the atmosphere, and (4) use of barriers to minimize the transport of tritium in groundwater. Continuing development efforts for tritium separations processes are primarily to support the International Thermonuclear Experimental Reactor (ITER) program, the nuclear power industry, and the production of radiochemicals. While these applications are significantly different than the Hanford application, the technology could potentially be adapted for Hanford wastewater treatment. Separations based processes to reduce tritium levels below the drinking water MCL have not been demonstrated for the scale and conditions required for treating Hanford wastewater. In addition, available cost information indicates treatment costs for such processes will be substantially higher than for discharge to SALDS or other typical pump and treat projects at Hanford. Actual mitigation projects for groundwater with very low tritium contamination similar to that found at Hanford have focused mainly on controlling migration and on evaporation for dispersion in the atmosphere.« less

The potential role of biochar in the removal of organic and microbial contaminants from potable and reuse water: A review.

PubMed

Inyang, Mandu; Dickenson, Eric

2015-09-01

In this work, the potential benefits, economics, and challenges of applying biochar in water treatment operations to remove organic and microbial contaminants was reviewed. Minimizing the use of relatively more expensive traditional sorbents in water treatment is a motivating aspect of biochar production, e.g., $246/ton non-activated biochar to $1500/ton activated carbon. Biochar can remove organic contaminants in water, such as some pesticides (0.02-23 mg g(-1)), pharmaceutical and personal care products (0.001-59 mg g(-1)), dyes (2-104 mg g(-1)), humic acid (60 mg g(-1)), perfluorooctane sulfonate (164 mg g(-1)), and N-nitrosomodimethylamine (3 mg g(-1)). Including adsorption/filtration applications, biochar can potentially be used to inactivate Escherichia coli via disinfection, and transform 95% of 2-chlorobiphenyl via advanced oxidation processes. However, more sorption data using biochar especially at demonstration-scale, for treating potable and reuse water in adsorption/filtration applications will help establish the potential of biochars to serve as surrogates for activated carbons. Copyright © 2015 Elsevier Ltd. All rights reserved.

Integrated copper-containing wastewater treatment using xanthate process.

PubMed

Chang, Yi-Kuo; Chang, Juu-En; Lin, Tzong-Tzeng; Hsu, Yu-Ming

2002-09-02

Although, the xanthate process has been shown to be an effective method for heavy metal removal from contaminated water, a heavy metal contaminated residual sludge is produced by the treatment process and the metal-xanthate sludge must be handled in accordance with the Taiwan EPA's waste disposal requirements. This work employed potassium ethyl xanthate (KEX) to remove copper ions from wastewater. The toxicity characteristic leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) were used to determine the leaching potential and stability characteristics of the residual copper xanthate (Cu-EX) complexes. Results from metal removal experiments showed that KEX was suitable for the treatment of copper-containing wastewater over a wide copper concentration range (50, 100, 500, and 1000 mg/l) to the level that meets the Taiwan EPA's effluent regulations (3mg/l). The TCLP results of the residual Cu-EX complexes could meet the current regulations and thus the Cu-EX complexes could be treated as a non-hazardous material. Besides, the results of SDLT indicated that the complexes exhibited an excellent performance for stabilizing metals under acidic conditions, even slight chemical changes of the complexes occurred during extraction. The xanthate process, mixing KEX with copper-bearing solution to form Cu-EX precipitates, offered a comprehensive strategy for solving both copper-containing wastewater problems and subsequent sludge disposal requirements.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Nigel; Lodge, Mike; Hilton, Linda

The nuclear industry is not a provider of oils and solvents but uses them in motors, equipment and even in chemical processes to extract valuable products. Currently, for old and contaminated oils and solvents, techniques still exist, such as incineration, but not all the oils and solvents are compatible with this technique because the activities of some components inside the oils are too high to be accepted at the incineration facility. For these oils, an alternative technique needs to be found for treatment. A process developed for water treatment using a technique of adsorption coupled with electrochemical regeneration has beenmore » investigated to assess its capability to treat these organic wastes. One of the strengths of the process is its flexibility and adaptation to different compositions of oils. This point is important because, in the AREVA case, there are a lot of small volumes of old oils which need to be re-characterized. It takes time and money to do it especially when oils are contaminated; this is one reason why the technique is interesting to investigate. Tests have been performed with different oils coming from different sites to test the feasibility. Results demonstrate the destruction of a range of organics with regeneration energy requirements of 13.4 - 68.7 kWh/l and offer confidence for the future potential of the process. (authors)« less

Reverse osmosis integrity monitoring in water reuse: The challenge to verify virus removal - A review.

PubMed

Pype, Marie-Laure; Lawrence, Michael G; Keller, Jurg; Gernjak, Wolfgang

2016-07-01

A reverse osmosis (RO) process is often included in the treatment train to produce high quality reuse water from treated effluent for potable purposes because of its high removal efficiency for salinity and many inorganic and organic contaminants, and importantly, it also provides an excellent barrier for pathogens. In order to ensure the continued protection of public health from pathogen contamination, monitoring RO process integrity is necessary. Due to their small sizes, viruses are the most difficult class of pathogens to be removed in physical separation processes and therefore often considered the most challenging pathogen to monitor. To-date, there is a gap between the current log credit assigned to this process (determined by integrity testing approved by regulators) and its actual log removal capability as proven in a variety of laboratory and pilot studies. Hence, there is a challenge to establish a methodology that more closely links to the theoretical performance. In this review, after introducing the notion of risk management in water reuse, we provide an overview of existing and potentially new RO integrity monitoring techniques, highlight their strengths and drawbacks, and debate their applicability to full-scale treatment plants, which open to future research opportunities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbial biosafety of pilot-scale bioreactor treating MTBE and TBA-contaminated drinking water supply.

PubMed

Schmidt, Radomir; Klemme, David A; Scow, Kate; Hristova, Krassimira

2012-03-30

A pilot-scale sand-based fluidized bed bioreactor (FBBR) was utilized to treat both methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) from a contaminated aquifer. To evaluate the potential for re-use of the treated water, we tested for a panel of water quality indicator microorganisms and potential waterborne pathogens including total coliforms, Escherichia coli, Salmonella and Shigella spp., Campylobacter jejuni, Aeromonas hydrophila, Legionella pneumophila, Vibrio cholerae, Yersinia enterocolytica and Mycobacterium avium in both influent and treated waters from the bioreactor. Total bacteria decreased during FBBR treatment. E. coli, Salmonella and Shigella spp., C. jejuni, V. cholerae, Y. enterocolytica and M. avium were not detected in aquifer water or bioreactor treated water samples. For those pathogens detected, including total coliforms, L. pneumophila and A. hydrophila, numbers were usually lower in treated water than influent samples, suggesting removal during treatment. The detection of particular bacterial species reflected their presence or absence in the influent waters. Copyright © 2012 Elsevier B.V. All rights reserved.

In situ removal of contamination from soil

DOEpatents

Lindgren, Eric R.; Brady, Patrick V.

1997-01-01

A process of remediation of cationic heavy metal contamination from soil utilizes gas phase manipulation to inhibit biodegradation of a chelating agent that is used in an electrokinesis process to remove the contamination, and further gas phase manipulation to stimulate biodegradation of the chelating agent after the contamination has been removed. The process ensures that the chelating agent is not attacked by bioorganisms in the soil prior to removal of the contamination, and that the chelating agent does not remain as a new contaminant after the process is completed.

Radioactive Water Treatment at a United States Environmental Protection Agency Superfund Site - 12322

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beckman, John C.

2012-07-01

A water treatment system at a United States Environmental Protection Agency (USEPA) Superfund site impacted by radiological contaminants is used to treat water entering the site. The United States Army Corps of Engineers (USACE) is actively managing the remedial action for the USEPA using contracts to support the multiple activities on site. The site is where former gas mantle production facilities operated around the turn of the century. The manufacturing facilities used thorium ores to develop the mantles and disposed of off-specification mantles and ore residuals in the surrounding areas. During Site remedial actions, both groundwater and surface water comesmore » into contact with contaminated soils and must be collected and treated at an on-site treatment facility. The radionuclides thorium and radium with associated progeny are the main concern for treatment. Suspended solids, volatile organic compounds, and select metals are also monitored during water treatment. The water treatment process begins were water is pumped to a collection tank where debris and grit settle out. Stored water is pumped to a coagulant tank containing poly-aluminum chloride to collect dissolved solids. The water passes into a reaction tube where aspirated air is added or reagent added to remove Volatile Organic Compounds (VOC'S) by mass transfer and convert dissolved iron to a solid. The water enters the flocculent polymer tank to drop solids out. The flocculated water overflows to a fluidized bed contact chamber to increase precipitation. Flocculation is where colloids of material drop out of suspension and settle. The settled solids are periodically removed and disposed of as radioactive waste. The water is passed through filters and an ion exchange process to extract the radionuclides. Several million liters of water are processed each year from two water treatment plants servicing different areas of the remediation site. Ion exchange resin and filter material are periodically replaced and disposed of as radioactive waste. A total of 0.85 m{sup 3} of waste sludge per year requires disposal on average, in addition to another 6.6 m{sup 3} of waste cartridge filters. All water discharges are regulated by a state of New Jersey Pollutant Discharge Elimination System Permit implemented by the Federal Water Pollution Control Act (Clean Water Act). Laboratory analyses are required to satisfy requirements of the state NPDES permit. Specific monitoring parameters and discharge rates will be provided. Use of the water treatment systems drastically reduces the amount of contaminated water requiring solidification and water disposal to near zero. Millions of liters of potentially contaminated water from excavation activities is treated and released within permit limits. A small volume of solid radioactive waste (21 cubic meters) is generated annually from water treatment process operations. Management of ground and surface water is effectively controlled in remediation areas by the use of sumps, erosion control measures and pumping of water to storage vessels. Continued excavations can be made as water impacting the site is effectively controlled. (authors)« less

LOW COST SOLIDIFICATION/STABILIZATION TREATMENT FOR SOILS CONTAMINATED WITH DIOXIN, PCP AND CREOSOTE

EPA Science Inventory

The USEPA's NRMRL conducted successful treatability tests of innovative solidification/stabilization (S/S) formulations to treat soils contaminated with dioxins, pentachlorophenol (PCP), and creosote from four wood preserving sites. Formulations developed during these studies wer...

LOW COST SOLIDIFICATION/STABILIZATION TREATMENT FOR SOILS CONTAMINATED WITH DIOXIN, PCP, AND CREOSOTE

EPA Science Inventory

The USEPA's National Risk Management Research Laboratory condcuted successful treatability tests of innovative solidification/stablization (S/S) formulations to treat soils contaminated with dioxins, pentachlorophenol (PCP), and creosote from four wood preserving sites. For one o...

DYNAPHORE, INC., FORAGER SPONGE TECHNOLOGY - INNOVATIVE TECHNOLOGY EVALUATION REPORT

EPA Science Inventory

The Forager Sponge is a volume reduction technology in which heavy metal contaminants from an aqueous medium are selectively concentrated into a smaller volume for facilitated disposal. he technology treats contaminated groundwater, surface voters and porous waters by absorbing d...

SITE TECHNOLOGY CAPSULE: DYNAPHORE, INC., FORAGER SPONGE TECHNOLOGY

EPA Science Inventory

The Forager Sponge is a volume reduction technology in which heavy metal contaminants from an aqueous medium are selectively concentrated into a smaller volume for facilitated disposal. he technology treats contaminated groundwater, surface waters and porous waters by absorbing d...

Assessment of exposures to fecally-contaminated recreational water

EPA Science Inventory

Exposure to fecally-contaminated recreational waters can pose a health risk to swimmers and other recreators. Since 2003, we have interviewed nearly 27,000 respondents at seven beaches impacted by treated sewage discharge. Information was collected about the duration and exposure...

BIOENHANCED IN-WELL VAPOR STRIPPING TO TREAT TRICHLOROETHYLENE(TCE)

EPA Science Inventory

Removal of chlorinated solvent contaminants at their subsurface source is one of the most challenging problems for remediation of these prevalent contaminants. Here, the solvents are generally present as dense non-aqueous phase liquids (DNAPLs). The potential for applicatio...

Arsenic Treatment Technologies for Soil, Waste, and Water

DTIC Science & Technology

2002-09-01

and Contaminants Treated Phytoremediation has been applied to contaminants from soil, surface water, groundwater, leachate , and municipal and...ELECTROKINETIC TREATMENT OF ARSENIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 - 1 15.0 PHYTOREMEDIATION ...14 - 5 15.1 Phytoremediation Treatment Performance Data for Arsenic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 - 5 16.1

Molecular Detection of Breast Cancer

DTIC Science & Technology

1998-02-01

treatment-resistant cancer cells. Clearly new approaches are needed to treat these diseases. This project is designed to develop novel approaches to...detect breast cancer cells that contaminate peripheral blood and bone marrow, and to remove such contaminating cells. An RT-PCR assay has been developed ...to detect breast cancer cells, and a novel gene therapy vector has been developed to kill contaminating cancer cells. Blood and bone marrow samples

Evaluation of the effect of indigenous mycogenic silver nanoparticles on soil exo-enzymes in barite mine contaminated soils

NASA Astrophysics Data System (ADS)

Gaddam, Durga Prameela; Devamma, Nagalakshmi; Prasad, Tollamadugu Naga Venkata Krishna Vara

2015-04-01

The biosynthesis of nanoparticles has received increasing attention due to the growing need to develop safe, cost-effective and environmentally friendly technologies for nanoscale materials synthesis. In this report, silver nanoparticles (AgNPs) were synthesized by treating aqueous Ag+ ions with the culture supernatants of indigenous fungal species of Fusarium solani isolated from barite mine contaminated soils. The formation of AgNPs might be an enzyme-mediated extracellular reaction process. The localized surface plasmon resonance of the formed AgNPs was recorded using UV-VIS spectrophotometer and was characterized using the techniques transmission electron microscopy, particle size analyzer, Fourier transform-infrared spectroscopy (FT-IR), particle size (dynamic light scattering) and zeta potential. The synthesized AgNPs were stable, polydispersed with the average size of 80 nm. FT-IR spectra reveals that proteins and carboxylic groups present in the fungal secrets might be responsible for the reduction and stabilization of the silver ions. Applied to the barite mine contaminated soils, concentration of AgNPs and incubation period significantly influences the soil exo-enzymatic activities, viz., urease, phosphatase, dehydrogenase and β-glucosidase. To the best of our knowledge, this is the first report on this kind of work in barite mine contaminated soils.

BTEX biodegradation by bacteria from effluents of petroleum refinery.

PubMed

Mazzeo, Dânia Elisa Christofoletti; Levy, Carlos Emílio; de Angelis, Dejanira de Franceschi; Marin-Morales, Maria Aparecida

2010-09-15

Groundwater contamination with benzene, toluene, ethylbenzene and xylene (BTEX) has been increasing, thus requiring an urgent development of methodologies that are able to remove or minimize the damages these compounds can cause to the environment. The biodegradation process using microorganisms has been regarded as an efficient technology to treat places contaminated with hydrocarbons, since they are able to biotransform and/or biodegrade target pollutants. To prove the efficiency of this process, besides chemical analysis, the use of biological assessments has been indicated. This work identified and selected BTEX-biodegrading microorganisms present in effluents from petroleum refinery, and evaluated the efficiency of microorganism biodegradation process for reducing genotoxic and mutagenic BTEX damage through two test-systems: Allium cepa and hepatoma tissue culture (HTC) cells. Five different non-biodegraded BTEX concentrations were evaluated in relation to biodegraded concentrations. The biodegradation process was performed in a BOD Trak Apparatus (HACH) for 20 days, using microorganisms pre-selected through enrichment. Although the biodegradation usually occurs by a consortium of different microorganisms, the consortium in this study was composed exclusively of five bacteria species and the bacteria Pseudomonas putida was held responsible for the BTEX biodegradation. The chemical analyses showed that BTEX was reduced in the biodegraded concentrations. The results obtained with genotoxicity assays, carried out with both A. cepa and HTC cells, showed that the biodegradation process was able to decrease the genotoxic damages of BTEX. By mutagenic tests, we observed a decrease in damage only to the A. cepa organism. Although no decrease in mutagenicity was observed for HTC cells, no increase of this effect after the biodegradation process was observed either. The application of pre-selected bacteria in biodegradation processes can represent a reliable and effective tool in the treatment of water contaminated with BTEX mixture. Therefore, the raw petroleum refinery effluent might be a source of hydrocarbon-biodegrading microorganisms. Copyright 2010 Elsevier B.V. All rights reserved.

Poisoned Playgrounds: Arsenic in "Pressure-Treated" Wood.

ERIC Educational Resources Information Center

Sharp, Renee; Walker, Bill

This study of 180 pressure-treated wood samples shows that treated wood is a much greater source of arsenic exposure for children than arsenic-contaminated drinking water. The report determines that an average 5-year-old, playing less than 2 weeks on a chromated-copper-arsenate-treated (CCA) wood play set would exceed the lifetime cancer risk…

Removal of contaminants and pathogens from secondary effluents using intermittent sand filters.

PubMed

Bali, Mahmoud; Gueddari, Moncef; Boukchina, Rachid

2011-01-01

Intermittent infiltration percolation of wastewater through unsaturated sand bed is an extensive treatment technique aimed at eliminating organic matter, oxidizing ammonium and removing pathogens. The main purpose of this study was to determine the depuration efficiencies of a sand filter to remove contaminants from secondary wastewater effluents. Elimination of pathogenic bacteria (total and faecal coliforms, streptococci) and their relationship with the filter depth were investigated. Results showed a high capacity of infiltration percolation process to treat secondary effluents. Total elimination of suspended solids was obtained. Mean removal rate of BOD(5) and COD was more than 97 and more than 81%, respectively. Other water quality parameters such as NH(4)-N, TKN and PO(4)-P showed significant reduction except NO(3)-N which increased significantly in the filtered water. Efficiency of pathogenic bacteria removal was shown to mainly depend on the filter depth. Average reductions of 2.35 log total coliforms, 2.47 log faecal coliforms and 2.11 log faecal streptococci were obtained. The experimental study has shown the influence of the temperature on the output purification of infiltration percolation process.

Effect of Bacillus subtilis and NTA-APG on pyrene dissipation in phytoremediation of nickel co-contaminated wetlands by Scirpus triqueter.

PubMed

Liu, Xiaoyan; Hu, Xiaoxin; Zhang, Xinying; Chen, Xueping; Chen, Jing; Yuan, Xiaoyu

2018-06-15

A complex mix of organic pollutants and heavy metal made the remediation of contaminated wetlands more difficult. Few research focus on the remediation for pyrene enhanced by chemical reagents and pyrene degrading bacteria in the nickel co-contaminated soil. In this paper, the effect of chemical reagents (nitrilotriacetic acid and alkyl polyglucoside) and Bacillus subtilis on pyrene dissipation in phytoremediation of nickel co-contaminated soil by Scirpus triqueter was investigated. Similar seedlings of Scirpus triqueter were moved to uncontaminated soil and pyrene-nickel co-contaminated soil. The pots (14.8 cm diameter and 8.8 cm height) were set up in greenhouse and treated in different ways. After 60 days, plant biomass, radial oxygen loss (ROL), soil dehydrogenase activity (DHA) and pyrene concentration in soil were determined. Results showed that ROL rate and DHA in different groups was positively correlated with pyrene dissipation from soil. In the process of remediation, chemical reagents might have an indirect slight effect on pyrene dissipation (pyrene dissipation increased 21%) by affecting DHA firstly and redistributing pyrene fractions in the presence of pyrene degrading bacteria. Pyrene degrading bacteria were likely to affect pyrene dissipation by impacting ROL rate and DHA and played a more vital role in contributing to pyrene dissipation (pyrene dissipation increased 45%) from wetland. This study demonstrated that phytoremediation for pyrene in nickel co-contaminated soil by Scirpus triqueter can be enhanced by the application of NTA-APG and pyrene degrading bacteria and they could be reasonably restore the ecological environment of PAH-contaminated wetlands. Copyright © 2018 Elsevier Inc. All rights reserved.

A sensitive biomarker for the detection of aquatic contamination based on behavioral assays using zebrafish larvae.

PubMed

Nüßer, Leonie K; Skulovich, Olya; Hartmann, Sarah; Seiler, Thomas-Benjamin; Cofalla, Catrina; Schuettrumpf, Holger; Hollert, Henner; Salomons, Elad; Ostfeld, Avi

2016-11-01

An effective biological early warning system for the detection of water contamination should employ undemanding species that rapidly react to the presence of contaminants in their environment. The demonstrated reaction should be comprehensible and unambiguously evidential of the contamination event. This study utilized 96h post fertilization zebrafish larvae and tested their behavioral response to acute exposure to low concentrations of cadmium chloride (CdCl2) (5.0, 2.5, 1.25, 0.625mg/L) and permethrin (0.05, 0.029, 0.017, 0.01μg/L). We hypothesize that the number of larvae that show advanced trajectories in a group corresponds with water contamination, as the latter triggers avoidance behavior in the organisms. The proportion of advanced trajectories in the control and treated groups during the first minute of darkness was designated as a segregation parameter. It was parametrized and a threshold value was set using one CdCl2 trial and then applied to the remaining CdCl2 and permethrin replicates. For all cases, the method allowed distinguishing between the control and treated groups within two cycles of light: dark. The calculated parameter was statistically significantly different between the treated and control groups, except for the lowest CdCl2 concentration (0.625mg/L) in one replicate. This proof-of-concept study shows the potential of the proposed methodology for utilization as part of a multispecies biomonitoring system. Copyright © 2016 Elsevier Inc. All rights reserved.

Ex situ bioremediation of oil-contaminated soil.

PubMed

Lin, Ta-Chen; Pan, Po-Tsen; Cheng, Sheng-Shung

2010-04-15

An innovative bioprocess method, Systematic Environmental Molecular Bioremediation Technology (SEMBT) that combines bioaugmentation and biostimulation with a molecular monitoring microarray biochip, was developed as an integrated bioremediation technology to treat S- and T-series biopiles by using the landfarming operation and reseeding process to enhance the bioremediation efficiency. After 28 days of the bioremediation process, diesel oil (TPH(C10-C28)) and fuel oil (TPH(C10-C40)) were degraded up to approximately 70% and 63% respectively in the S-series biopiles. When the bioaugmentation and biostimulation were applied in the beginning of bioremediation, the microbial concentration increased from approximately 10(5) to 10(6) CFU/g dry soil along with the TPH biodegradation. Analysis of microbial diversity in the contaminated soils by microarray biochips revealed that Acinetobacter sp. and Pseudomonas aeruginosa were the predominant groups in indigenous consortia, while the augmented consortia were Gordonia alkanivorans and Rhodococcus erythropolis in both series of biopiles during bioremediation. Microbial respiration as influenced by the microbial activity reflected directly the active microbial population and indirectly the biodegradation of TPH. Field experimental results showed that the residual TPH concentration in the complex biopile was reduced to less than 500 mg TPH/kg dry soil. The above results demonstrated that the SEMBT technology is a feasible alternative to bioremediate the oil-contaminated soil. Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.

In situ field application of electrokinetic remediation for an As-, Cu-, and Pb-contaminated rice paddy site using parallel electrode configuration.

PubMed

Jeon, Eun-Ki; Jung, Ji-Min; Ryu, So-Ri; Baek, Kitae

2015-10-01

The applicability of an in situ electrokinetic process with a parallel electrode configuration was evaluated to treat an As-, Cu-, and Pb-contaminated paddy rice field in full scale (width, 17 m; length, 12.2 m; depth, 1.6 m). A constant voltage of 100 V was supplied and electrodes were spaced 2 m apart. Most As, Cu, and Pb were bound to Fe oxide and the major clay minerals in the test site were kaolinite and muscovite. The electrokinetic system removed 48.7, 48.9, and 54.5 % of As, Cu, and Pb, respectively, from the soil during 24 weeks. The removal of metals in the first layer (0-0.4 m) was higher than that in the other three layers because it was not influenced by groundwater fluctuation. Fractionation analysis showed that As and Pb bound to amorphous Fe and Al oxides decreased mainly, and energy consumption was 1.2 kWh/m(3). The standard deviation of metal concentration in the soil was much higher compared to the hexagonal electrode configuration because of a smaller electrical active area; however, the electrode configuration removed similar amounts of metals compared to the hexagonal system. From these results, it was concluded that the electrokinetic process could be effective at remediating As-, Cu-, and Pb-contaminated paddy rice field in situ.

Transport and fate of organic wastes in groundwater at the Stringfellow hazardous waste disposal site, southern California

USGS Publications Warehouse

Leenheer, J.A.; Hsu, J.; Barber, L.B.

2001-01-01

In January 1999, wastewater influent and effluent from the pretreatment plant at the Stringfellow hazardous waste disposal site were sampled along with groundwater at six locations along the groundwater contaminant plume. The objectives of this sampling and study were to identify at the compound class level the unidentified 40-60% of wastewater organic contaminants, and to determine what organic compound classes were being removed by the wastewater pretreatment plant, and what organic compound classes persisted during subsurface waste migration. The unidentified organic wastes are primarily chlorinated aromatic sulfonic acids derived from wastes from DDT manufacture. Trace amounts of EDTA and NTA organic complexing agents were discovered along with carboxylate metabolites of the common alkylphenolpolyethoxylate plasticizers and nonionic surfactants. The wastewater pretreatment plant removed most of the aromatic chlorinated sulfonic acids that have hydrophobic neutral properties, but the p-chlorobenzenesulfonic acid which is the primary waste constituent passed through the pretreatment plant and was discharged in the treated wastewaters transported to an industrial sewer. During migration in groundwater, p-chlorobenzenesulfonic acid is removed by natural remediation processes. Wastewater organic contaminants have decreased 3- to 45-fold in the groundwater from 1985 to 1999 as a result of site remediation and natural remediation processes. The chlorinated aromatic sulfonic acids with hydrophobic neutral properties persist and have migrated into groundwater that underlies the adjacent residential community. Copyright ?? 2001 .

NUTRIENT CONTAMINATION AS A RESULT OF POINT SOURCE DISCHARGES: A SURVEY

EPA Science Inventory

Nutrients are common contaminants in Gulf of Mexico estuaries and when present in high concentrations, they can cause excessive algal growths and hypoxic conditions. The magnitude and biological significance of nutrient loading to estuarine waters receiving treated wastewaters is...

PERMEABLE REACTIVE BARRIERS FOR IN-SITU TREATMENT OF ARSENIC-CONTAMINATED GROUNDWATER

EPA Science Inventory

Laboratory and field research has shown that permeable reactive barriers (PRBs) containing a variety of materials can treat arsenic (As) contaminated groundwater. Sites where these PRBs are located include a mine tailings facility, fertilizer and chemical manufacturing sites, a...

DEMONSTRATION OF BULLETIN: DISC TUBE™ MODULE TECHNOLOGY ROCHEM SEPARATION SYSTEMS, INC.

EPA Science Inventory

The Rochem Disc Tube™ Module System uses membrane separation to treat aqueous solutions ranging from seawater to leachate contaminated with organic solvents. The system uses reverse osmosis through a semipermeable membrane to separate purified water from contaminated liquids. Osm...

ASSESSMENT OF BIOFILTER MEDIA PARTICLE SIZES FOR REMOVING AMMONIA

USDA-ARS?s Scientific Manuscript database

With increased concerns over odor and gas emissions from livestock production facilities more efficient technologies of air pollution control are needed to mitigate the deleterious effects of air contaminants. Gas-phase biofilters for treating contaminant gases from poultry and livestock operations ...

Assessment of Biofilter Media Particle Sizes for Removing Ammonia

USDA-ARS?s Scientific Manuscript database

With increased concerns over odor and gas emissions from livestock production facilities more efficient technologies of air pollution control are needed to mitigate the deleterious effects of air contaminants. Gas-phase biofilters for treating contaminant gases from poultry and livestock operations ...

Evaluating the Adsorptive Capabilites of Chemsorb 1000 and Chemsorb 1425

NASA Technical Reports Server (NTRS)

Mejia, Oscar Alberto Monje; Surma, Jan M.; Johnsey, Marissa; Melendez, Orlando

2014-01-01

The removal of trace contaminants from spacecraft cabin air is necessary for crew health and comfort during long duration space exploration missions. The air revitalization technologies used in these future exploration missions will evolve from current ISS ISS State-of-Art (SOA) and is being designed and tested by the Advanced Exploration Systems (AES) Program's Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project. The ARREM project is working to mature optimum atmosphere revitalization and environmental monitoring system architectures to enable exploration beyond Lower Earth Orbit (LEO). The Air Revitalization Lab at KSC is one of six NASA field centers participating in the ARREM that specializes in adsorbent and catalyst characterization with simulated spacecraft gas streams using combinations of pressure, O2 partial pressure, CO2 partial pressure, and humidity that are representative of a range of anticipated cabin atmospheric conditions and loads. On board ISS, the Trace Contaminant Control Subassembly (TCCS) provides active control of trace contaminants from the cabin atmosphere utilizing physical adsorption, thermal catalytic oxidation, and chemical adsorption processes. High molecular weight contaminants and ammonia (NH3) are removed a granular activated carbon treated with approx. 10% by weight phosphoric acid (H3PO4) (B-S Type 3032 4×6 mesh), which is expendable and is periodically refurbished. The Type 3032 granular activated carbon bed is no longer commercially available and therefore it is important to characterize the efficiency and capacity of commercially available NH3 sorbents. This paper describes the characterization of two Molecular Products LTD activated carbons: Chemsorb 1000 and Chemsorb 1425. Untreated activated carbons (e.g. Chemsorb 1000) remove contaminants by physisorption, which concentrates the contaminant within the pores of the carbon while letting air to pass through the sorbent4. Low molecular weight or polar gases (e.g. HCl, SO2, formaldehyde, and NH3) are not removed by physisorption and typically require chemisorption for removal. Treated activated carbons (e.g. Chemsorb 1425) are impregnated with a a chemical agent (e.g. phosphoric acid) that reacts with those gases, converting them to solids or salts within the carbon and removes them from the air stream. This process occurs via neutralization or catalysis reactions and adsorption capacity is exhaustedwhen the available impregnated chemicals are consumed. Moisture affects removal performance since adsorption sites within the pores are filled with water. The performance of impregnated carbons may be enhanced by moisture content because the mechanisms of contaminant removal are chemical reactions that occur in reagents contained within the pores. The adsorptive capacity data (mol/kg) of Chemsorb 1000 and 1425 for gas mixtures (ethanol, acetone, toluene, acetaldehyde, dichloromethane, and xylene) was measured with 40% relative humidity at 23 deg C air temperature. The adsorptive capacity data (mol/kg) of Chemsorb 1425 was measured using NH3 gas streams.

Soil Contamination and Remediation Strategies. Current research and future challenge

NASA Astrophysics Data System (ADS)

Petruzzelli, G.

2012-04-01

Soil contamination: the heritage of industrial development Contamination is only a part of a whole set of soil degradation processes, but it is one of paramount importance since soil pollution greatly influences the quality of water, food and human health. Soil contamination has been identified as an important issue for action in the European strategy for soil protection, it has been estimated that 3.5 million of sites are potentially contaminated in Europe. Contaminated soils have been essentially discovered in industrial sites landfills and energy production plants, but accumulation of heavy metals and organic compounds can be found also in agricultural land . Remediation strategies. from incineration to bioremediation The assessment of soil contamination is followed by remedial action. The remediation of contaminated soils started using consolidates technologies (incineration inertization etc.) previously employed in waste treatment,. This has contributed to consider a contaminated soil as an hazardous waste. This rough approximation was unfortunately transferred in many legislations and on this basis soil knowledge have been used only marginally in the clean up procedures. For many years soil quality has been identified by a value of concentration of a contaminant and excavation and landfill disposal of soil has been largely used. In the last years the knowledge of remediation technology has rapidly grown, at present many treatment processes appear to be really feasible at field scale, and soil remediation is now based on risk assessment procedures. Innovative technologies, largely dependent on soil properties, such as in situ chemical oxidation, electroremediation, bioventing, soil vapor extraction etc. have been successfully applied. Hazardous organic compounds are commonly treated by biological technologies, biorememdiation and phytoremediation, being the last partially applied also for metals. Technologies selection is no longer exclusively based on eliminating the source of pollution, but also on blocking the pathways from contaminants to receptors or reducing the exposure to contaminants,. Future challenge integration of sustainability into remediation decision-making. Soil is not a waste! There is a growing interest in the clean up approaches that maintain soil quality after remediation treatments. This issue is of great importance in the U.S.A. where the EPA from 2009 is promoting innovative clean-up strategies (Green Remediation). Green remediation is defined as the practice of considering all environmental effects of remedy and incorporating options to maximize environmental benefit of cleanup actions . These remediation strategies restore contaminated sites to productive use with a great attention to the global environmental quality, including the preservation of soil functionality according to the following principles: use minimally invasive technologies; use passive energy technologies such as bioremediation and phytoremediation as primary remedies or finishing steps where possible and effective; minimize soil and habitat disturbance; minimize bioavailability of contaminants trough adequate contaminant source and plume control If we move from the current definition of remedial targets based on total concentrations, technologies with low impact on the environment can be utilized reducing the wrong choice to disposal soil in landfill destroying quickly a not renewable essential resource.

Improved radiocarbon dating for contaminated archaeological bone collagen, silk, wool and hair samples via cross-flow nanofiltrated amino acids.

PubMed

Boudin, Mathieu; Boeckx, Pascal; Vandenabeele, Peter; Van Strydonck, Mark

2013-09-30

Radiocarbon dating and stable isotope analyses of bone collagen, wool, hair and silk contaminated with extraneous carbon (e.g. humic substances) does not yield reliable results if these materials are pre-treated using conventional methods. A cross-flow nanofiltration method was developed that can be applied to various protein materials like collagen, hair, silk, wool and leather, and should be able to remove low-molecular and high-molecular weight contaminants. To avoid extraneous carbon contamination via the filter a ceramic filter (molecular weight cut-off of 200 Da) was used. The amino acids, released by hot acid hydrolysis of the protein material, were collected in the permeate and contaminants in the retentate (>200 Da). (14)C-dating results for various contaminated archaeological samples were compared for bulk material (pre-treated with the conventional methods) and for cross-flow nanofiltrated amino acids (permeate) originating from the same samples. Contamination and quality control of (14)C dates of bulk and permeate samples were obtained by measuring C:N ratios, fluorescence spectra, and δ(13)C and δ(15)N values of the samples. Cross-flow nanofiltration decreases the C:N ratio which means that contaminants have been removed. Cross-flow nanofiltration clearly improved sample quality and (14)C results. It is a quick and non-labor-intensive technique and can easily be implemented in any (14)C and stable isotope laboratory for routine sample pre-treatment analyses. Copyright © 2013 John Wiley & Sons, Ltd.

The performance and decolourization kinetics of O3/H2O2 oxidation of reactive green 19 dye in wastewater

NASA Astrophysics Data System (ADS)

Sabri, S. N.; Abidin, C. Z. A.; Fahmi; Kow, S. H.; Razali, N. A.

2018-03-01

The degradations characteristic of azo dye Reactive Green 19 (RG19) was investigated using advanced oxidation process (AOPs). It was evaluated based on colour and chemical oxygen demand (COD) removal. The effect of operational parameters such as initial dye concentration, initial dosage of hydrogen peroxide (H2O2), contact time, and pH was also being studied. The samples were treated by ozonation (O3) and peroxone O3/H2O2 process. Advanced oxidation processes (AOPs) involve two stages of oxidation; firstly is the formation of strong oxidant and secondly the reaction of organic contaminants in water. In addition, the term advanced oxidation is referring to the processes in which oxidation of organic contaminants occurs primarily through reactions with hydroxyl radicals. There are several analyses that use to determine the efficiency of the treatment process, which are UV-Vis absorption spectra, COD, Fourier Transform Infrared (FT-IR), and pH. The results demonstrated that the ozone oxidation was efficient in decolourization and good in mineralization, based on the reduction of colour and COD. Additionally, results indicate that H2O2 is able to perform better than ozonation in order to decolourize the dye wastewater with 0.5 mL H2O2/L dye dosage of H2O2 at different initial concentration, initial pH, with contact time.

Spatial interpolation methods and geostatistics for mapping groundwater contamination in a coastal area.

PubMed

Elumalai, Vetrimurugan; Brindha, K; Sithole, Bongani; Lakshmanan, Elango

2017-04-01

Mapping groundwater contaminants and identifying the sources are the initial steps in pollution control and mitigation. Due to the availability of different mapping methods and the large number of emerging pollutants, these methods need to be used together in decision making. The present study aims to map the contaminated areas in Richards Bay, South Africa and compare the results of ordinary kriging (OK) and inverse distance weighted (IDW) interpolation techniques. Statistical methods were also used for identifying contamination sources. Na-Cl groundwater type was dominant followed by Ca-Mg-Cl. Data analysis indicate that silicate weathering, ion exchange and fresh water-seawater mixing are the major geochemical processes controlling the presence of major ions in groundwater. Factor analysis also helped to confirm the results. Overlay analysis by OK and IDW gave different results. Areas where groundwater was unsuitable as a drinking source were 419 and 116 km 2 for OK and IDW, respectively. Such diverse results make decision making difficult, if only one method was to be used. Three highly contaminated zones within the study area were more accurately identified by OK. If large areas are identified as being contaminated such as by IDW in this study, the mitigation measures will be expensive. If these areas were underestimated, then even though management measures are taken, it will not be effective for a longer time. Use of multiple techniques like this study will help to avoid taking harsh decisions. Overall, the groundwater quality in this area was poor, and it is essential to identify alternate drinking water source or treat the groundwater before ingestion.

Phytotreatment of soil contaminated with used lubricating oil using Hibiscus cannabinus.

PubMed

Abioye, O P; Agamuthu, P; Abdul Aziz, A R

2012-04-01

Soil contamination by hydrocarbons, especially by used lubricating oil, is a growing problem in developing countries, which poses a serious threat to the environment. Phytoremediation of these contaminated soils offers environmental friendly and a cost effective method for their remediation. Hibiscus cannabinus was studied for the remediation of soil contaminated with 2.5 and 1% used lubricating oil and treated with organic wastes [banana skin (BS), brewery spent grain (BSG) and spent mushroom compost (SMC)] for a period of 90 days under natural conditions. Loss of 86.4 and 91.8% used lubricating oil was recorded in soil contaminated with 2.5 and 1% oil and treated with organic wastes respectively at the end of 90 days. However, 52.5 and 58.9% oil loss was recorded in unamended soil contaminated with 2.5 and 1% oil, respectively. The plant did not accumulate hydrocarbon from the soil but shows appreciable accumulation of Fe and Zn in the root and stem of H. cannabinus at the end of the experiment. The first order kinetic rate of uptake of Fe and Zn in H. cannabinus was higher in organic wastes amendment treatments compared to the unamended treatments, which are extremely low. The results of this study suggest that H. cannabinus has a high potential for remediation of hydrocarbon and heavy metal contaminated soil.

Factors affecting the distribution of hydrocarbon contaminants and hydrogeochemical parameters in a shallow sand aquifer

NASA Astrophysics Data System (ADS)

Lee, Jin-Yong; Cheon, Jeong-Yong; Lee, Kang-Kun; Lee, Seok-Young; Lee, Min-Hyo

2001-07-01

The distributions of hydrocarbon contaminants and hydrogeochemical parameters were investigated in a shallow sand aquifer highly contaminated with petroleum hydrocarbons leaked from solvent storage tanks. For these purposes, a variety of field investigations and studies were performed, which included installation of over 100 groundwater monitoring wells and piezometers at various depths, soil logging and analyses during well and piezometer installation, chemical analysis of groundwater, pump tests, and slug tests. Continuous water level monitoring at three selected wells using automatic data-logger and manual measuring at other wells were also conducted. Based on analyses of the various investigations and tests, a number of factors were identified to explain the distribution of the hydrocarbon contaminants and hydrogeochemical parameters. These factors include indigenous biodegradation, hydrostratigraphy, preliminary pump-and-treat remedy, recharge by rainfall, and subsequent water level fluctuation. The permeable sandy layer, in which the mean water table elevation is maintained, provided a dominant pathway for contaminant transport. The preliminary pump-and-treat action accelerated the movement of the hydrocarbon contaminants and affected the redox evolution pattern. Seasonal recharge by rain, together with indigenous biodegradation, played an important role in the natural attenuation of the petroleum hydrocarbons via mixing/dilution and biodegradation. The water level fluctuations redistributed the hydrocarbon contaminants by partitioning them into the soil and groundwater. The identified factors are not independent but closely inter-correlated.

Application of a high-level peracetic acid disinfection protocol to re-process antibiotic disinfected skin allografts.

PubMed

Lomas, R J; Huang, Q; Pegg, D E; Kearney, J N

2004-01-01

Skin allografts, derived from cadaveric donors, are widely used for the treatment of burns and ulcers. Prior to use in clinical situations, these allografts are disinfected using a cocktail of antibiotics and then cryopreserved. Unfortunately, this antibiotic disinfection procedure fails to decontaminate a significant proportion and these contaminated grafts can not be used clinically. We have investigated whether it is possible to apply a second, more potent disinfection procedure to these contaminated grafts and effectively to re-process them for clinical use. Cadaveric skin grafts, treated with antibiotics and cryopreserved, were thawed and a peracetic acid (PAA) disinfection protocol applied. The grafts were then preserved in a high concentration of glycerol or propylene glycol, and properties thought to be essential for successful clinical performance assessed. The cytotoxicity of the grafts was assessed using both extract and contact assays; damage to the skin collagen was assessed using a collagenase susceptibility assay and the capacity of the grafts to elicit an inflammatory response in vitro was assessed by quantifying the production of the pro-inflammatory cytokine TNF-alpha by human peripheral blood mononuclear phagocytes. PAA disinfection, in conjunction with either glycerol or propylene glycol preservation, did not render the grafts cytotoxic, pro-inflammatory, or increase their susceptibility to collagenase digestion. The rates of penetration of glycerol and propylene glycol into the re-processed skin were comparable to those of fresh skin. This study has demonstrated that PAA disinfection combined with immersion in high concentrations of either glycerol or propylene glycol was an effective method for re-processing contaminated skin allografts, and may justify their clinical use.

Effect of Soil Slope on the Appearance of Mycobacterium avium subsp. paratuberculosis in Water Running off Grassland Soil after Application of Contaminated Slurry

PubMed Central

Alfaro, M.; Salazar, F.; Troncoso, E.; Mitchell, R. M.; Ramirez, L.; Naguil, A.; Zamorano, P.; Collins, M. T.

2013-01-01

The study assessed the effect of soil slope on Mycobacterium avium subsp. paratuberculosis transport into rainwater runoff from agricultural soil after application of M. avium subsp. paratuberculosis-contaminated slurry. Under field conditions, 24 plots of undisturbed loamy soil 1 by 2 m2 were placed on platforms. Twelve plots were used for water runoff: 6 plots at a 3% slope and 6 plots at a 15% slope. Half of the plots of each slope were treated with M. avium subsp. paratuberculosis-contaminated slurry, and half were not treated. Using the same experimental design, 12 plots were established for soil sampling on a monthly basis using the same spiked slurry application and soil slopes. Runoff following natural rainfall was collected and analyzed for M. avium subsp. paratuberculosis, coliforms, and turbidity. M. avium subsp. paratuberculosis was detected in runoff from all plots treated with contaminated slurry and one control plot. A higher slope (15%) increased the likelihood of M. avium subsp. paratuberculosis detection but did not affect the likelihood of finding coliforms. Daily rainfall increased the likelihood that runoff would have coliforms and the coliform concentration, but it decreased the M. avium subsp. paratuberculosis concentration in the runoff. When there was no runoff, rain was associated with increased M. avium subsp. paratuberculosis concentrations. Coliform counts in runoff were related to runoff turbidity. M. avium subsp. paratuberculosis presence/absence, however, was related to turbidity. Study duration decreased bacterial detection and concentration. These findings demonstrate the high likelihood that M. avium subsp. paratuberculosis in slurry spread on pastures will contaminate water runoff, particularly during seasons with high rainfall. M. avium subsp. paratuberculosis contamination of water has potential consequences for both animal and human health. PMID:23542616

Use of the Threshold of Toxicological Concern (TTC) approach for deriving target values for drinking water contaminants.

PubMed

Mons, M N; Heringa, M B; van Genderen, J; Puijker, L M; Brand, W; van Leeuwen, C J; Stoks, P; van der Hoek, J P; van der Kooij, D

2013-03-15

Ongoing pollution and improving analytical techniques reveal more and more anthropogenic substances in drinking water sources, and incidentally in treated water as well. In fact, complete absence of any trace pollutant in treated drinking water is an illusion as current analytical techniques are capable of detecting very low concentrations. Most of the substances detected lack toxicity data to derive safe levels and have not yet been regulated. Although the concentrations in treated water usually do not have adverse health effects, their presence is still undesired because of customer perception. This leads to the question how sensitive analytical methods need to become for water quality screening, at what levels water suppliers need to take action and how effective treatment methods need to be designed to remove contaminants sufficiently. Therefore, in the Netherlands a clear and consistent approach called 'Drinking Water Quality for the 21st century (Q21)' has been developed within the joint research program of the drinking water companies. Target values for anthropogenic drinking water contaminants were derived by using the recently introduced Threshold of Toxicological Concern (TTC) approach. The target values for individual genotoxic and steroid endocrine chemicals were set at 0.01 μg/L. For all other organic chemicals the target values were set at 0.1 μg/L. The target value for the total sum of genotoxic chemicals, the total sum of steroid hormones and the total sum of all other organic compounds were set at 0.01, 0.01 and 1.0 μg/L, respectively. The Dutch Q21 approach is further supplemented by the standstill-principle and effect-directed testing. The approach is helpful in defining the goals and limits of future treatment process designs and of analytical methods to further improve and ensure the quality of drinking water, without going to unnecessary extents. Copyright © 2013 Elsevier Ltd. All rights reserved.

Wastewater treatments and the impact on environment and agriculture: A case city of Annaba (north eastern of Algeria)

NASA Astrophysics Data System (ADS)

Abour, Fella; Hannouche, Mani; Belksier, Mohamed Salah

2018-05-01

The present study deals with wastewater treatment which represents a real challenge in the world especially for developing countries. Our investigation takes place in the Annaba (North Eastern of Algeria) which represents one of big cities in the country. The wastewater is treated collectively in the Allalik station which provides a global wastewater treatment to guarantee the sustainability of the ecosystem. The obtained results on treated wastewater show a contamination with Selenium (IS index for Selenium = 5.9). Whereas the other analysed parameters highlight values without exceeding standards excepting the nitrites. The microbiological analyses and Bourgeois index indicate the human origin for pollution (IB >1). In spite of the actual treatment, the pollution selenium and nitrites suggest the improvement of the process of wastewater treatment.

Feasibility studies for the treatment and reuse of contaminated marine sediments.

PubMed

Bonomoa, L; Careghini, A; Dastoli, S; De Propris, L; Ferrari, G; Gabellini, M; Saponaro, S

2009-07-01

This paper presents preliminary results of laboratory tests aimed at evaluating the easibility of the remediation of marine sediments, which are polluted by mercury and petroleum hydrocarbons, dredged at the bay of Augusta (SR, Italy). The treatment is composed of two sequential steps: in the first, a cement-based granular material is produced (based on a high performance concrete approach); then, the volatile and the semi-volatile compounds in the granular material are removed by a thermal desorption step. Treated materials could be reused or put into caissons, according to their mechanical properties and environmental compatibility. The experiments were focused on evaluating the effect of the process parameter values on: (i) the evolution of cement hydration reactions, (ii) thermal desorption removal efficiencies, (iii) leaching behaviour of the treated material.

Factors affecting the microbiological condition of the deep tissues of mechanically tenderized beef.

PubMed

Gill, C O; McGinnis, J C

2005-04-01

Whole or halved top butt prime beef cuts were treated in two types of mechanical tenderizing machines that both pierced the meat with thin blades but that used blades of different forms. Aerobes on meat surfaces and in the deep tissues of cuts after treatments were counted. When cuts were treated at a laboratory using a Lumar machine, the contamination of deep tissues increased significantly (P < 0.01) with increasing numbers of aerobic bacteria on meat surfaces and decreased significantly (P < 0.001) with increasing distance from the incised surface. However, contamination did not increase significantly (P > 0.1) with repeated incising of the meat. When halved cuts were incised one or eight times using a commercially cleaned Ross machine at a retail store, the numbers of aerobes recovered from deep tissues were similar with both treatments. When halved cuts were treated in one or other machine, deep tissue contamination was greater with the Lumar machine than with the Ross machine. Contamination of deep tissues as a result of tenderizing by piercing with thin blades can be minimized if the blades are designed to limit the number of bacteria carried into the meat and the microbiological condition of incised surface is well controlled.

Immunological and physiological effects of chronic exposure of Peromyscus leucopus to Aroclor 1254 at a concentration similar to that found at contaminated sites

USGS Publications Warehouse

Segre, M.; Arena, S.M.; Greeley, E.H.; Melancon, M.J.; Graham, D.A.; French, J.B.

2002-01-01

Polychlorinated biphenyls (PCBs) are environmental contaminants known to cause adverse health effects to biological systems. Limited data are available on their effects on the immune system of wildlife species. Previously, we found that 4 and 6-week-old white-footed mice (Peromyscus leucopus) born from dams injected with a single dose (300 mg/kg) of Aroclor 1254, had altered immunological, hematological, and biochemical responses. Here, we examined the effect of transplacental lactational and postnatal exposure to Aroclor 1254, at a concentration similar to that found at contaminated sites, on various physiological parameters of 22-week-old white-footed mice. Liver weight and liver somatic index of PCB treated animals were significantly higher, the combined weights of the adrenal glands were significantly lower and EROD and BROD enzyme activity was significantly higher compared to control values. The number of thymocytes of the treated mice was significantly lower than that of the controls; however, thymocytes of treated mice had a higher proliferative response to the mitogen Con A. These alterations were correlated with the PCBs body burdens. Some toxic effects of chronic exposure to PCBs, at levels comparable to exposure found in contaminated sites in the USA, are still evident in adult P. leucopus.

Implications of Bioremediation of Polycyclic Aromatic Hydrocarbon-Contaminated Soils for Human Health and Cancer Risk.

PubMed

Davie-Martin, Cleo L; Stratton, Kelly G; Teeguarden, Justin G; Waters, Katrina M; Simonich, Staci L Massey

2017-09-05

Bioremediation uses soil microorganisms to degrade polycyclic aromatic hydrocarbons (PAHs) into less toxic compounds and can be performed in situ, without the need for expensive infrastructure or amendments. This review provides insights into the cancer risks associated with PAH-contaminated soils and places bioremediation outcomes in a context relevant to human health. We evaluated which bioremediation strategies were most effective for degrading PAHs and estimated the cancer risks associated with PAH-contaminated soils. Cancer risk was statistically reduced in 89% of treated soils following bioremediation, with a mean degradation of 44% across the B2 group PAHs. However, all 180 treated soils had postbioremediation cancer risk values that exceeded the U.S. Environmental Protection Agency (USEPA) health-based acceptable risk level (by at least a factor of 2), with 32% of treated soils exceeding recommended levels by greater than 2 orders of magnitude. Composting treatments were most effective at biodegrading PAHs in soils (70% average reduction compared with 28-53% for the other treatment types), which was likely due to the combined influence of the rich source of nutrients and microflora introduced with organic compost amendments. Ultimately, bioremediation strategies, in the studies reviewed, were unable to successfully remove carcinogenic PAHs from contaminated soils to concentrations below the target cancer risk levels recommended by the USEPA.

Microbiologic contamination during dental radiographic film processing.

PubMed

Stanczyk, D A; Paunovich, E D; Broome, J C; Fatone, M A

1993-07-01

This study investigated microbiologic contamination of an automatic dental radiograph processor and daylight loader during a week of simulated clinical use. Pure cultures of Candida albicans, Streptococcus pneumoniae, Staphylococcus aureus, or Klebsiella pneumoniae were used to contaminate 320 vinyl intraoral radiograph packets. Each end of the films was deliberately contaminated during opening. These films and 24 uncontaminated control films were processed. Daylight loader ports, inlet and outlet rollers, fixer and developer samples, and 12 processed films were cultured daily. To simulate a weekend, the processor sites were cultured during 72 hours of inactivity after the contaminated runs. The results showed that contamination of the processor and daylight loader occurred and remained even after 48 hours of inactivity. Films remained contaminated after processing. In addition, cross-contamination of films occurred in the processor.

Removal of dissolved textile dyes from wastewater by a compost sorbent

USGS Publications Warehouse

Tsui, L.S.; Roy, W.R.; Cole, M.A.

2003-01-01

The objective of this study was to evaluate the potential for treating dye-contaminated waste streams by sorption using compost as a low-cost sorbent. A mature, thermophilic compost sample was used to sorb CI Acid Black 24, CI Acid Orange 74, CI Basic Blue 9, CI Basic Green 4, CI Direct Blue 71, CI Direct Orange 39, CI Reactive Orange 16 and CI Reactive Red 2 from solution using a batch-sorption method. With the exception of the two reactive dyes, the sorption kinetics were favourable for a continuous-flow treatment process with the compost-dye mixtures reaching a steady state within 3-5 h. Based on limited comparisons, the affinity of the compost for each dye appeared to be competitive with other non-activated carbon sorbents. The results suggest that additional research on using compost as a sorbent for dye-contaminated solutions is warranted.

Dielectric Barrier Discharge Plasma-Induced Photocatalysis and Ozonation for the Treatment of Wastewater

NASA Astrophysics Data System (ADS)

Mok, Young Sun; Jo, Jin-Oh; Lee, Heon-Ju

2008-02-01

The physicochemical processes of dielectric barrier discharge (DBD) such as in-situ formation of chemically active species and emission of ultraviolet (UV)/visible light were utilized for the treatment of a simulated wastewater formed with Acid Red 4 as the model organic contaminant. The chemically active species (mostly ozone) produced in the DBD reactor were well distributed in the wastewater using a porous gas diffuser, thereby increasing the gas-liquid contact area. For the purpose of making the best use of the light emission, a titanium oxide-based photocatalyst was incorporated in the wastewater treating system. The experimental parameters chosen were the voltage applied to the DBD reactor, the initial pH of the wastewater, and the concentration of hydrogen peroxide added to the wastewater. The results have clearly shown that the present system capable of degrading organic contaminants in two ways (photocatalysis and ozonation) may be a promising wastewater treatment technology.

Chemical stabilization of metals and arsenic in contaminated soils using oxides--a review.

PubMed

Komárek, Michael; Vaněk, Aleš; Ettler, Vojtěch

2013-01-01

Oxides and their precursors have been extensively studied, either singly or in combination with other amendments promoting sorption, for in situ stabilization of metals and As in contaminated soils. This remediation option aims at reducing the available fraction of metal(loid)s, notably in the root zone, and thus lowering the risks associated with their leaching, ecotoxicity, plant uptake and human exposure. This review summarizes literature data on mechanisms involved in the immobilization process and presents results from laboratory and field experiments, including the subsequent influence on higher plants and aided phytostabilization. Despite the partial successes in the field, recent knowledge highlights the importance of long-term and large-scale field studies evaluating the stability of the oxide-based amendments in the treated soils and their efficiency in the long-term. Copyright © 2012 Elsevier Ltd. All rights reserved.

Critical evaluation of municipal solid waste composting and potential compost markets.

PubMed

Farrell, M; Jones, D L

2009-10-01

Mechanical biological treatment (MBT) of mixed waste streams is becoming increasingly popular as a method for treating municipal solid waste (MSW). Whilst this process can separate many recyclates from mixed waste, the resultant organic residue can contain high levels of heavy metals and physical and biological contaminants. This review assesses the potential end uses and sustainable markets for this organic residue. Critical evaluation reveals that the best option for using this organic resource is in land remediation and restoration schemes. For example, application of MSW-derived composts at acidic heavy metal contaminated sites has ameliorated soil pollution with minimal risk. We conclude that although MSW-derived composts are of low value, they still represent a valuable resource particularly for use in post-industrial environments. A holistic view should be taken when regulating the use of such composts, taking into account the specific situation of application and the environmental pitfalls of alternative disposal routes.

A fluidized bed membrane bioelectrochemical reactor for energy-efficient wastewater treatment.

PubMed

Li, Jian; Ge, Zheng; He, Zhen

2014-09-01

A fluidized bed membrane bioelectrochemical reactor (MBER) was investigated using fluidized granular activated carbon (GAC) as a mean of membrane fouling control. During the 150-day operation, the MBER generated electricity with contaminant removal from either synthetic solution or actual wastewater, as a standalone or a coupled system. It was found that fluidized GAC could significantly reduce transmembrane pressure (TMP), although its function as a part of the anode electrode was minor. When the MBER was linked to a regular microbial fuel cell (MFC) for treating a wastewater from a cheese factory, the MFC acted as a major process for energy recovery and contaminant removal, and the coupled system removed more than 90% of chemical oxygen demand and >80% of suspended solids. The analysis showed that the ratio of energy recovery and consumption was slightly larger than one, indicating that the coupled system could be theoretically energy neutral. Copyright © 2014 Elsevier Ltd. All rights reserved.

Molasses as an external carbon source for anaerobic treatment of sulphite evaporator condensate.

PubMed

Silva, Flávio; Nadais, Helena; Prates, António; Arroja, Luís; Capela, Isabel

2009-03-01

Failures in stability and COD removal performance often occurred in full-scale anaerobic reactors treating the evaporator condensate from a sulphite pulp mill due to substrate inhibition and occasional contaminations with red liquor (wood cooking liquor). With this work, the beneficial effect provided by the continuous addition of an external carbon source (sugarcane molasses) on the overall performance and stability of the biological process was evaluated. With a moderate addition of molasses the inhibition was mitigated which led to an increase of the COD removal rate from 52% to 77% and a methane production increase from 460 to 1650mld(-1) at an organic loading rate of 2.61g CODl(-1)d(-1). A similar conclusion can be drawn for the case when contamination with red liquor occurs. These results suggest that sugarcane molasses addition may be regarded as a low-cost operational strategy for the anaerobic treatment of sulphite evaporator condensate.

Chemical, physical, and radiological quality of selected public water supplies in Florida, February-April 1980

USGS Publications Warehouse

Franks, Bernard J.; Irwin, G.A.

1981-01-01

Virtually all treated public water supplies in Florida meet the National Interim Primary and Secondary Drinking Water Regulations. These findings are based on a water-quality reconnaissance of 126 raw and treated public water supplies throughout the State during the period February through April 1980. Primary drinking water regulations maximum contaminant levels were rarely exceeded, although mercury (1 site), fluoride (2 sites), and radionuclides (3 sites) in water supplies were above established maximum contaminant levels. Dissolved solids, chloride, copper, manganese, iron, color, sulfate, and pH, were occasionally slightly in excess of the recommended maximum contaminant levels of the secondary drinking water regulation. The secondary regulations, however, pertain mainly to the esthetic quality of drinking water and not directly to public health aspects. (USGS)

Estimating virus occurrence using Bayesian modeling in multiple drinking water systems of the United States.

PubMed

Varughese, Eunice A; Brinkman, Nichole E; Anneken, Emily M; Cashdollar, Jennifer L; Fout, G Shay; Furlong, Edward T; Kolpin, Dana W; Glassmeyer, Susan T; Keely, Scott P

2018-04-01

Drinking water treatment plants rely on purification of contaminated source waters to provide communities with potable water. One group of possible contaminants are enteric viruses. Measurement of viral quantities in environmental water systems are often performed using polymerase chain reaction (PCR) or quantitative PCR (qPCR). However, true values may be underestimated due to challenges involved in a multi-step viral concentration process and due to PCR inhibition. In this study, water samples were concentrated from 25 drinking water treatment plants (DWTPs) across the US to study the occurrence of enteric viruses in source water and removal after treatment. The five different types of viruses studied were adenovirus, norovirus GI, norovirus GII, enterovirus, and polyomavirus. Quantitative PCR was performed on all samples to determine presence or absence of these viruses in each sample. Ten DWTPs showed presence of one or more viruses in source water, with four DWTPs having treated drinking water testing positive. Furthermore, PCR inhibition was assessed for each sample using an exogenous amplification control, which indicated that all of the DWTP samples, including source and treated water samples, had some level of inhibition, confirming that inhibition plays an important role in PCR-based assessments of environmental samples. PCR inhibition measurements, viral recovery, and other assessments were incorporated into a Bayesian model to more accurately determine viral load in both source and treated water. Results of the Bayesian model indicated that viruses are present in source water and treated water. By using a Bayesian framework that incorporates inhibition, as well as many other parameters that affect viral detection, this study offers an approach for more accurately estimating the occurrence of viral pathogens in environmental waters. Published by Elsevier B.V.

Hydrogeologic Effects of In-Situ Groundwater Treatment Using Biodegradation

DTIC Science & Technology

1987-06-15

development of groundwater divides, 2 * removal of contaminated water through pumping foillowed by above ground treatment, Excavating the contaminant source... water infiltration. During in-situ bioreclama- tion the pol:uted extracted groundwater is often treated, and after addition of nutrients and oxygen...1982, "Degrada- tion of phenolic contaminants in groundwater by aerobic bacteria: St. Louis Park, Minnesota", Ground Water , Vol.20, No.6, pp.703-710

The EDTA Amendment in Phytoextraction of (134)Cs From Soil by Indian Mustard (Brassica juncea).

PubMed

Tjahaja, Poppy Intan; Sukmabuana, Putu; Roosmini, Dwina

2015-01-01

Soil contamination with radiocaesium is a significant problem at any countries when a nuclear accident occurred. Recently, phytoextraction technique is developed to remediate the contaminated environment. However, the application is limited by the availability of the contaminant for root uptake. Therefore, a green house trial experiment of soil amendment with ethylene diamine tetraacetic acid (EDTA) has been conducted to examine (134)Cs availability for root uptake. Two groups of Indian mustard (Brassica juncea) were cultivated in (134)Cs contaminated soil. The soil in the first group was treated with EDTA amendment, while the other was not. Plant growth was observed gravimetrically and the (134)Cs concentration in soil as well as plants were determined using gamma spectrometry. The plant uptake capacity was determined as transfer factor (Fv), and the Fv values of 0.22 ± 0.0786 and 0.12 ± 0.039 were obtained for the soil treated with and without EDTA amendment, respectively. The phytoextraction efficiency of the plant cultivated in (134)Cs contaminated soil both with and without EDTA amendment was low. The EDTA amendment to the soil seems to enhance the (134)Cs availability for root uptake of Indian mustard and can still be considered to assist the field phytoremediation of contaminated soil.

PILOT-SCALE INCINERATION OF CONTAMINATED SLUDGES FROM THE BOFORS-NOBEL SUPERFUND SITE

EPA Science Inventory

A detailed test program was performed at the U.S. Environmental Protection Agency’s (EPA’s) Incineration Research Facility (IRF) to help determine the effectiveness of incineration in treating two contaminated lagoon sludges from the Bofors-Nobel Superfund site in Mus...

SUPERFUND TREATABILITY CLEARINGHOUSE: BDAT FOR SOLIDIFICATION/STABILIZATION TECHNOLOGY FOR SUPERFUND SOILS (DRAFT FINAL REPORT)

EPA Science Inventory

This report evaluates the performance of solidification as a method for treating solids from Superfund sites. Tests were conducted on four different artificially contaminated soils which are representative of soils found at the sites. Contaminated soils were solidified us...

LAND TREATMENT OF TWO PLATEAU MATERIALS CONTAMINATED WITH PAHS

EPA Science Inventory

This study was designed to evaluate several treatments for their ability to enhance the biological removal of polycyclic aromatic hydrocarbons (PAHs) from contaminated soil and sediment. Previously land-treated material was used to test the treatments in a 13 week bench scale stu...

SITE DEMONSTRATION BULLETIN: SOIL RECYCLING TREATMENT TRAIN - THE TORONTO HARBOUR COMMISSIONERS

EPA Science Inventory

The Toronto Harbour Commissioners (THC) have developed a soil treatment train designed to treat inorganic and organic contaminants in soils. THC has conducted a large-scale demonstration of these technologies in an attempt to establish that contaminated soils at the Toronto Port...

TORONTO HARBOUR COMMISSIONERS (THC) SOIL RECYCLE TREATMENT TRAIN - APPLICATIONS ANALYSIS REPORT

EPA Science Inventory

The Toronto Harbour Commissioners (THC) have developed a soil treatment train designed to treat inorganic and organic contaminants in soils. THC has conducted a large-scale demonstration of these technologies in an attempt to establish that contaminated soils at the Toronto Port ...

LAND TREATMENT AND THE TOXICITY RESPONSE OF SOIL CONTAMINATED WITH WOOD PRESERVING WASTE

EPA Science Inventory

Soils contaminated with wood preserving wastes, including pentachlo-rophenol (PCP) and creosote, are treated at field-scale in an engineered prepared-bed system consisting of two one-acre land treatment units (LTUs). The concentration of selected indicator compounds of treatment ...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farina, R.; Brandao-Mello, C.E.; Oliveira, A.R.

In September 1987, the Goiania radiological accident involving a source of {sup 137}Cs culminated in about 140 victims who presented internal and/or external contamination and/or external exposure to radiation and/or radiation burns. Internal contamination was verified through analysis of urine and fecal samples. Internal contamination was also evaluated by measurements performed at the whole-body counter installed in Goiania in November 1987. To enhance the decorporation of 137Cs, patients were treated with the following: (1) Prussian Blue, oral administration, in 46 patients; (2) diuretics, oral administration, in 17 patients; (3) induced perspiration, increasing {sup 137}Cs elimination. These procedures were done undermore » rigorous clinical evaluation and considering the data from assay of excreta and data obtained from the whole-body counter. The doses of Prussian Blue exceeded about 6.5 times the dose previously indicated in the literature. It was the first time diuretics were used in humans to treat {sup 137}Cs internal contamination. The results of these procedures are discussed.« less

The transmission of Fasciola spp. to cattle and contamination of grazing areas with Fasciola eggs in the Red River Delta region of Vietnam.

PubMed

Lan Anh, Nguyen Thi; Thanh, Dao Thi Ha; Hoan, Doan Huu; Thuy, Do Thu; Khong, Nguyen Viet; Anderson, Norman

2014-04-01

At four times during November 2010, cattle with infections of Fasciola spp., in two communes of northern Vietnam, were allocated to two equivalent groups. Cattle in one group were treated with triclabendazole. Faecal samples collected monthly from both groups were tested for Fasciola copro-antigens and the presence of Fasciola eggs. Re-infection of treated cattle occurred from early March to late November, coinciding with high weekly totals of rainfall. Contamination of grazing areas by untreated cattle was high and relatively constant throughout the year. However, contamination was reduced to undetectable amounts for 8 to 12 weeks after treatment and even at 20 weeks was only 50% or less of the pre-treatment amounts. Therefore, treatments given in mid-September and again in early April, at the start of the wet season, may be sufficient to prevent contamination of grazing areas and reduce the prevalence and severity of Fasciola infections in cattle.

Green Remediation Best Management Practices: Pump and Treat Technologies

EPA Pesticide Factsheets

The U.S. EPA Principles for Greener Cleanups outline the Agency's policy for evaluating and minimizing the environmental 'footprint' of activities undertaken when cleaning up a contaminated site with pump and treat technologies.

Chemical Enhancements to Pump-and-Treat Remediation

EPA Pesticide Factsheets

The intent of this document is to explore the use of chemical enhancement to improve groundwater remediation efficiencies using pump-and-treat technologies, and point out arenas of contamination where such techniques are not practical.

Actinobacteria consortium as an efficient biotechnological tool for mixed polluted soil reclamation: Experimental factorial design for bioremediation process optimization.

PubMed

Aparicio, Juan Daniel; Raimondo, Enzo Emanuel; Gil, Raúl Andrés; Benimeli, Claudia Susana; Polti, Marta Alejandra

2018-01-15

The objective of the present work was to establish optimal biological and physicochemical parameters in order to remove simultaneously lindane and Cr(VI) at high and/or low pollutants concentrations from the soil by an actinobacteria consortium formed by Streptomyces sp. M7, MC1, A5, and Amycolatopsis tucumanensis AB0. Also, the final aim was to treat real soils contaminated with Cr(VI) and/or lindane from the Northwest of Argentina employing the optimal biological and physicochemical conditions. In this sense, after determining the optimal inoculum concentration (2gkg -1 ), an experimental design model with four factors (temperature, moisture, initial concentration of Cr(VI) and lindane) was employed for predicting the system behavior during bioremediation process. According to response optimizer, the optimal moisture level was 30% for all bioremediation processes. However, the optimal temperature was different for each situation: for low initial concentrations of both pollutants, the optimal temperature was 25°C; for low initial concentrations of Cr(VI) and high initial concentrations of lindane, the optimal temperature was 30°C; and for high initial concentrations of Cr(VI), the optimal temperature was 35°C. In order to confirm the model adequacy and the validity of the optimization procedure, experiments were performed in six real contaminated soils samples. The defined actinobacteria consortium reduced the contaminants concentrations in five of the six samples, by working at laboratory scale and employing the optimal conditions obtained through the factorial design. Copyright © 2017 Elsevier B.V. All rights reserved.

Application of a transmission model to estimate performance objectives for Salmonella in the broiler supply chain.

PubMed

van der Fels-Klerx, H J; Tromp, S; Rijgersberg, H; van Asselt, E D

2008-11-30

The aim of the present study was to demonstrate how Performance Objectives (POs) for Salmonella at various points in the broiler supply chain can be estimated, starting from pre-set levels of the PO in finished products. The estimations were performed using an analytical transmission model, based on prevalence data collected throughout the chain in The Netherlands. In the baseline (current) situation, the end PO was set at 2.5% of the finished products (at end of processing) being contaminated with Salmonella. Scenario analyses were performed by reducing this baseline end PO to 1.5% and 0.5%. The results showed the end PO could be reduced by spreading the POs over the various stages of the broiler supply chain. Sensitivity analyses were performed by changing the values of the model parameters. Results indicated that, in general, decreasing Salmonella contamination between points in the chain is more effective in reducing the baseline PO than increasing the reduction of the pathogen, implying contamination should be prevented rather than treated. Application of both approaches at the same time showed to be most effective in reducing the end PO, especially at the abattoir and during processing. The modelling approach of this study proved to be useful to estimate the implications for preceding stages of the chain by setting a PO at the end of the chain as well as to evaluate the effectiveness of potential interventions in reducing the end PO. The model estimations may support policy-makers in their decision-making process with regard to microbiological food safety.

Effects of lead mineralogy on soil washing enhanced by ferric salts as extracting and oxidizing agents.

PubMed

Yoo, Jong-Chan; Park, Sang-Min; Yoon, Geun-Seok; Tsang, Daniel C W; Baek, Kitae

2017-10-01

In this study, we evaluated the feasibility of using ferric salts including FeCl 3 and Fe(NO 3 ) 3 as extracting and oxidizing agents for a soil washing process to remediate Pb-contaminated soils. We treated various Pb minerals including PbO, PbCO 3 , Pb 3 (CO 3 ) 2 (OH) 2 , PbSO 4 , PbS, and Pb 5 (PO 4 ) 3 (OH) using ferric salts, and compared our results with those obtained using common washing agents of HCl, HNO 3 , disodium-ethylenediaminetetra-acetic acid (Na 2 -EDTA), and citric acid. The use of 50 mM Fe(NO 3 ) 3 extracted significantly more Pb (above 96% extraction) from Pb minerals except PbSO 4 (below 55% extraction) compared to the other washing agents. In contrast, washing processes using FeCl 3 and HCl were not effective for extraction from Pb minerals because of PbCl 2 precipitation. Yet, the newly formed PbCl 2 could be dissolved by subsequent wash with distilled water under acidic conditions. When applying our washing method to remediate field-contaminated soil from a shooting range that had high concentrations of Pb 3 (CO 3 ) 2 (OH) 2 and PbCO 3 , we extracted more Pb (approximately 99% extraction) from the soil using 100 mM Fe(NO 3 ) 3 than other washing agents at the same process conditions. Our results show that ferric salts can be alternative washing agents for Pb-contaminated soils in view of their extracting and oxidizing abilities. Copyright © 2017 Elsevier Ltd. All rights reserved.

The spectroscopic detection of drugs of abuse in fingerprints after development with powders and recovery with adhesive lifters

NASA Astrophysics Data System (ADS)

West, Matthew J.; Went, Michael J.

2009-01-01

The application of powders to fingerprints has long been established as an effective and reliable method for developing latent fingerprints. Fingerprints developed in situ at a crime scene routinely undergo lifting with specialist tapes and are then stored in evidence bags to allow secure transit and also to preserve the chain of evidence. In a previous study we have shown that exogenous material within a fingerprint can be detected using Raman spectroscopy following development with powders and lifting with adhesive tapes. Other reports have detailed the use of Raman spectroscopy to the detection of drugs of abuse in latent fingerprints including cyanoacrylate-fumed fingerprints. This study involves the application of Raman spectroscopy for the analysis of drugs of abuse in latent fingerprints for fingerprints that had been treated with powders and also subsequently lifted with adhesive tapes. Samples of seized ecstasy, cocaine, ketamine and amphetamine were supplied by East Sussex Police and by the TICTAC unit at St. Georges Hospital Tooting. Contaminated fingerprints were deposited on clean glass slides. The application of aluminium or iron based powders to contaminated fingerprints did not interfere with the Raman spectra obtained for the contaminants. Contaminated fingerprints developed with powders and then lifted with lifting tapes were also examined. The combination of these two techniques did not interfere with the successful analysis. The lifting process was repeated using hinge lifters. As the hinge lifters exhibited strong Raman bands the spectroscopic analysis was more complex and an increase in the number of exposures to the detector allowed for improved clarification. Spectral subtraction was performed to remove peaks due to the hinge lifters using OMNIC software. Raman spectra of developed and lifted fingerprints recorded through evidence bags were obtained and it was found that the detection process was not compromised. Although the application of powders did not interfere with the detection process the time taken to locate the contaminant was increased due to the physical presence of more material within the fingerprint.

The spectroscopic detection of drugs of abuse in fingerprints after development with powders and recovery with adhesive lifters.

PubMed

West, Matthew J; Went, Michael J

2009-01-01

The application of powders to fingerprints has long been established as an effective and reliable method for developing latent fingerprints. Fingerprints developed in situ at a crime scene routinely undergo lifting with specialist tapes and are then stored in evidence bags to allow secure transit and also to preserve the chain of evidence. In a previous study we have shown that exogenous material within a fingerprint can be detected using Raman spectroscopy following development with powders and lifting with adhesive tapes. Other reports have detailed the use of Raman spectroscopy to the detection of drugs of abuse in latent fingerprints including cyanoacrylate-fumed fingerprints. This study involves the application of Raman spectroscopy for the analysis of drugs of abuse in latent fingerprints for fingerprints that had been treated with powders and also subsequently lifted with adhesive tapes. Samples of seized ecstasy, cocaine, ketamine and amphetamine were supplied by East Sussex Police and by the TICTAC unit at St. Georges Hospital Tooting. Contaminated fingerprints were deposited on clean glass slides. The application of aluminium or iron based powders to contaminated fingerprints did not interfere with the Raman spectra obtained for the contaminants. Contaminated fingerprints developed with powders and then lifted with lifting tapes were also examined. The combination of these two techniques did not interfere with the successful analysis. The lifting process was repeated using hinge lifters. As the hinge lifters exhibited strong Raman bands the spectroscopic analysis was more complex and an increase in the number of exposures to the detector allowed for improved clarification. Spectral subtraction was performed to remove peaks due to the hinge lifters using OMNIC software. Raman spectra of developed and lifted fingerprints recorded through evidence bags were obtained and it was found that the detection process was not compromised. Although the application of powders did not interfere with the detection process the time taken to locate the contaminant was increased due to the physical presence of more material within the fingerprint.

Engineering aspects of ferrate in water and wastewater treatment - a review.

PubMed

Yates, Brian J; Zboril, Radek; Sharma, Virender K

2014-01-01

There is renewed interest in the tetra-oxy compound of +6 oxidation states of iron, ferrate(VI) (Fe(VI)O4(2-)), commonly called ferrate. Ferrate has the potential in cleaner ("greener") technologies for water treatment and remediation processes, as it produces potentially less toxic byproducts than other treatment chemicals (e.g., chlorine). Ferrate has strong potential to oxidize a number of contaminants, including sulfur- and nitrogen-containing compounds, estrogens, and antibiotics. This oxidation capability of ferrate combines with its efficient disinfection and coagulation properties as a multi-purpose treatment chemical in a single dose. This review focuses on the engineering aspects of ferrate use at the pilot scale to remove contaminants in and enhance physical treatment of water and wastewater. In most of the pilot-scale studies, in-line and on-line electrochemical ferrate syntheses have been applied. In this ferrate synthesis, ferrate was directly prepared in solution from an iron anode, followed by direct addition to the contaminant stream. Some older studies applied ferrate as a solid. This review presents examples of removing a range of contaminants by adding ferrate solution to the stream. Results showed that ferrate alone and in combination with additional coagulants can reduce total suspended solids (TSS), chemical oxygen demand (COD), biological oxygen demand (BOD), and organic matter. Ferrate also oxidizes cyanide, sulfide, arsenic, phenols, anilines, and dyes and disinfects a variety of viruses and bacteria. Limitations and drawbacks of the application of ferrate in treating contaminated water on the pilot scale are also presented.

Surfactant effects on desorption rate of nonionic organic compounds from soils to water

USGS Publications Warehouse

Cesare, David Di; Smith, James A.

1994-01-01

The widespread occurrence of organic contamination in groundwater systems has become an important environmental concern. Of particular interest are nonionic organic compounds, which sorb strongly to natural soil as a result of their characteristic low aqueous solubilities and hydrophobic nature. Consequently, the remediation of nonionic organic contamination in groundwater systems is often highly dependent on contaminant desorption from the sorbed to aqueous phase. The kinetics of desorption will significantly influence the extraction efficiency of pump-and-treat remedial methods that are capable of removing only dissolved phase contaminants.

Examples from the Greenland-Project - Gentle Remediation Optiones (GROs) on Pb/zn Contaminated Sites

NASA Astrophysics Data System (ADS)

Friesl-Hanl, Wolfgang; Kidd, Petra; Siebielec, Grzegorz

2017-04-01

The GREENLAND-project brought together "best practice" examples of several field applied gentle remediation techniques (EUFP7-project "Gentle remediation of trace element-contaminated land - GREENLAND; www.greenland-project.eu) with 17 partners from 11 countries. Gentle remediation options (GRO) comprise environmentally friendly technologies that have little or no negative impact on the soil. The main technologies are • phytoextraction • in situ immobilization and • assisted phytostabilization. Mining and processing activities affecting many sites worldwide negatively. The huge amounts of moved and treated materials have led to considerable flows of wastes and emissions. Alongside the many advantages of processed ores to our society, adverse effects in nature and risks for the environment and human health are observed. Three stages of impact of Pb/Zn-ore-treatment on the environment are discussed here: (1) On sites where the ores are mined impacts are the result of crushing, grinding, concentrating activities, and where additionally parts of the installations remain after abandoning the mine, as well as by the massive amounts of remaining deposits or wastes (mine tailings). (2) On sites where smelting and processing takes place, depending on the process (Welz, Doerschel) different waste materials are deposited. The Welz process waste generally contains less Cd and Pb than the Doerschel process waste which additionally shows higher water- extractable metals. (3) On sites close to the emitting source metal contamination can be found in areas for housing, gardening, and agricultural use. Emissions consist mainly from oxides and sulfides (Zn, Cd), sulfates (Zn, Pb, and Cd), chlorides (Pb) and carbonates (Cd). All these wastes and emissions pose potential risks of dispersion of pollutants into the food chain due to erosion (wind, water), leaching and the transfer into feeding stuff and food crops. In-situ treatments have the potential for improving the situation on site and will be shown by means of field experiments in Spain, Poland and Austria. Keywords: Mining and smelting, in-situ remediation, phytomanagement, gentle remediation options

Deep Aquifer Remediation Tools (DARTs): A new technology for ground-water remediation

USGS Publications Warehouse

Naftz, David L.; Davis, James A.

1999-01-01

Potable ground-water supplies throughout the world are contaminated or threatened by advancing plumes containing radionuclides, metals, and organic compounds. Currently (1999), the most widely used method of ground-water remediation is a combination of extraction, ex-situ treatment, and discharge of the treated water, commonly known as pump and treat. Pump-and-treat methods are costly and often ineffective in meeting long-term protection standards (Travis and Doty, 1990; Gillham and Burris, 1992; National Research Council, 1994). This fact sheet describes a new and potentially cost-effective technology for removal of organic and inorganic contaminants from ground water. The U.S. Geological Survey (USGS) is currently exploring the possibilities of obtaining a U.S. Patent for this technology.

Perfluoroalkyl acids in municipal landfill leachates from China: Occurrence, fate during leachate treatment and potential impact on groundwater.

PubMed

Yan, Hong; Cousins, Ian T; Zhang, Chaojie; Zhou, Qi

2015-08-15

Raw and treated landfill leachate samples were collected from 5 municipal landfill sites in China to measure the concentrations and contamination profile of perfluoroalkyl acids (PFAAs) in leachate during different steps of treatment. The total concentration of PFAAs (∑PFAAs) ranged from 7280 to 292,000 ng L(-1) in raw leachate and from 98.4 to 282,000 ng L(-1) in treated leachate. The dominant compounds measured were PFOA (mean contribution 28.8% and 36.8% in raw and treated leachate, respectively) and PFBS (26.1% and 40.8% in raw and treated leachate, respectively). A calculation of mass flows during the leachate treatment processes showed that the fate of individual PFAAs was substance and treatment-specific. The Chinese national leakage of ∑PFAAs to groundwater from landfill leachate was estimated to be 3110 kg year(-1), which is a significant environmental release that is potentially threatening the sustainable use of groundwater as a drinking water source. Copyright © 2015 Elsevier B.V. All rights reserved.

Bioavailability of TNT residues in composts of TNT-contaminated soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palmer, W.G.; Beaman, J.R.; Walters, D.M.

1997-10-01

Composting is being explored as a means to remediate 2,4,6-trinitrotoluene (TNT) contaminated soils. This process appears to modify TNT and to bind it to organic matter. The health hazards associated with dusts generated from such materials cannot be predicted without knowing if the association between TNT residues and compost particulate is stable in biological systems. To address this question, single doses of [{sup 14}C]-TNT, soil spiked with [{sup 14C]-TNT, or compost generated with [{sup 14}C]-TNT-spiked soils were administered to rats by intratracheal instillation. The appearance of {sup 14}C in urine and tissues was taken as an indication of the bioavailabilitymore » of TNT residues from compost particles. In rats instilled with neat [{sup 14}C]-TNT, about 35% of the {sup 14}C dose appeared in urine within 3 d. The {sup 14}C excreted in urine by these rats decreased rapidly thereafter, and was undetectable by 4 wk after treatment. Similar results were obtained with soil-treated rats. In contrast, after treatment with [{sup 14}C]-TNT-labeled compost, only 2.3% of the total {sup 14}C dose appeared in urine during the first 3 d. Low levels of {sup 14}C continued to be excreted in urine from compost-treated rats for more than 6 mo, and the total amount of {sup 14}C in urine was comparable to that in TNT-treated animals. Determination of the radiolabel in tissues showed that {sup 14}C accumulated in the kidneys of rats treated with labeled compost but not in rats treated with [{sup 14}C]-TNT or [{sup 14}C]-TNT-spiked soil. These results indicate that the association between TNT and particulate matter in compost is not stable when introduced into the lungs. Accumulation of {sup 14}C in kidneys suggests the presence of a unique TNT residue in compost-treated rats. The rate of excretion and tissue disposition of {sup 14}}C in rats treated with TNT-spiked soil indicate that TNT in soil is freely available in the lungs. 12 refs., 4 figs., 1 tab.« less

Performance evaluation of a mitogenome capture and Illumina sequencing protocol using non-probative, case-type skeletal samples: Implications for the use of a positive control in a next-generation sequencing procedure.

PubMed

Marshall, Charla; Sturk-Andreaggi, Kimberly; Daniels-Higginbotham, Jennifer; Oliver, Robert Sean; Barritt-Ross, Suzanne; McMahon, Timothy P

2017-11-01

Next-generation ancient DNA technologies have the potential to assist in the analysis of degraded DNA extracted from forensic specimens. Mitochondrial genome (mitogenome) sequencing, specifically, may be of benefit to samples that fail to yield forensically relevant genetic information using conventional PCR-based techniques. This report summarizes the Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory's (AFMES-AFDIL) performance evaluation of a Next-Generation Sequencing protocol for degraded and chemically treated past accounting samples. The procedure involves hybridization capture for targeted enrichment of mitochondrial DNA, massively parallel sequencing using Illumina chemistry, and an automated bioinformatic pipeline for forensic mtDNA profile generation. A total of 22 non-probative samples and associated controls were processed in the present study, spanning a range of DNA quantity and quality. Data were generated from over 100 DNA libraries by ten DNA analysts over the course of five months. The results show that the mitogenome sequencing procedure is reliable and robust, sensitive to low template (one ng control DNA) as well as degraded DNA, and specific to the analysis of the human mitogenome. Haplotypes were overall concordant between NGS replicates and with previously generated Sanger control region data. Due to the inherent risk for contamination when working with low-template, degraded DNA, a contamination assessment was performed. The consumables were shown to be void of human DNA contaminants and suitable for forensic use. Reagent blanks and negative controls were analyzed to determine the background signal of the procedure. This background signal was then used to set analytical and reporting thresholds, which were designated at 4.0X (limit of detection) and 10.0X (limit of quantiation) average coverage across the mitogenome, respectively. Nearly all human samples exceeded the reporting threshold, although coverage was reduced in chemically treated samples resulting in a ∼58% passing rate for these poor-quality samples. A concordance assessment demonstrated the reliability of the NGS data when compared to known Sanger profiles. One case sample was shown to be mixed with a co-processed sample and two reagent blanks indicated the presence of DNA above the analytical threshold. This contamination was attributed to sequencing crosstalk from simultaneously sequenced high-quality samples to include the positive control. Overall this study demonstrated that hybridization capture and Illumina sequencing provide a viable method for mitogenome sequencing of degraded and chemically treated skeletal DNA samples, yet may require alternative measures of quality control. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Removal of Dissolved Salts and Particulate Contaminants from Seawater: Village Marine Tec., Expeditionary Unit Water Purifier, Generation 1

EPA Science Inventory

The EUWP was developed to treat challenging water sources with variable turbidity, chemical contamination, and very high total dissolved solids (TDS), including seawater, during emergency situations when other water treatment facilities are incapacitated. The EUWP components incl...

USE OF MEMBRANE BIOREACTOR FOR BIODEGRADATION OF MTBE IN CONTAMINATED WATER1

EPA Science Inventory

An ultrafiltration membrane bioreactor was evaluated for biodegradation of methyl tert-butyl ether (MTBE) in contaminated water. The system was fed 5 mg/L MTBE in granular activated carbon (GAC) treated Cincinnati tap water containing ample buffer and nutrients. Within 120...

A novel inhibitor of Lactobacillus biofilms prevents stuck fermentations in a shake flask model

USDA-ARS?s Scientific Manuscript database

Yeast ethanol fermentations contain contaminating bacteria and yeast, with Lactobacilli being a frequent contaminant. These bacteria tolerate the low pH and high ethanol concentrations present in the fermentation, and can decrease the ethanol yield. Fermentations are routinely treated with antibioti...

Prevention of Salmonella cross-contamination in an oilmeal manufacturing plant.

PubMed

Morita, T; Kitazawa, H; Iida, T; Kamata, S

2006-08-01

The mechanisms of Salmonella contamination in an oilmeal plant were investigated and the basic data were collected in order to achieve control of Salmonella in oilmeal. Salmonella was detected in all contamination vectors and environmental factors investigated, namely: operators, processing floor, dust in the air and rodents. In particular, high concentrations of Salmonella were detected on the processing floor of the manufacturing area, which has high oil content. Steam was the most effective disinfection method used for the processing floor, as the effects of heat sterilization and disinfection may work in tandem. In addition, restricting the movement of operators of the production chain remarkably reduced Salmonella contamination, even in areas of otherwise high contamination. Within the oilmeal plant, high Salmonella contamination rates for the processing floor represent the greatest risk of contamination of oilmeal via operators, dust in the air and rodents. Therefore, control of the processing floor is the most important means for reducing the oilmeal contamination rate. Specific Salmonella control methods for oilmeal plants have been established.

Economic evaluation of a combined photo-Fenton/MBR process using pesticides as model pollutant. Factors affecting costs.

PubMed

Sánchez Pérez, José Antonio; Román Sánchez, Isabel María; Carra, Irene; Cabrera Reina, Alejandro; Casas López, José Luis; Malato, Sixto

2013-01-15

The aim of this paper is to carry out an economic assessment on a solar photo-Fenton/MBR combined process to treat industrial ecotoxic wastewater. This study focuses on the impact of the contamination present in wastewater, the photochemical oxidation, the use of an MBR as biological process and the plant size on operating and amortization costs. As example of ecotoxic pollutant, a mixture of five commercial pesticides commonly used in the Mediterranean area has been used, ranging from 500 mg/L to 50mg/L, expressed as dissolved organic carbon concentration. The economic evaluation shows that (i) the increase in pollution load does not always involve an increase in photo-Fenton costs because they also depend on organic matter mineralization; (ii) the use of an MBR process permits lower photochemical oxidation requirements than other biological treatments, resulting in approximately 20% photo-Fenton cost reduction for highly polluted wastewater; (iii) when pollution load decreases, the contribution of reactant consumption to the photo-Fenton process costs increase with regard to amortization costs; (iv) 30% total cost reduction can be gained treating higher daily volumes, obtaining competitive costs that vary from 1.1-1.9 €/m(3), depending on the pollution load. Copyright © 2012 Elsevier B.V. All rights reserved.

Demonstration of base catalyzed decomposition process, Navy Public Works Center, Guam, Mariana Islands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidt, A.J.; Freeman, H.D.; Brown, M.D.

1996-02-01

Base Catalyzed Decomposition (BCD) is a chemical dehalogenation process designed for treating soils and other substrate contaminated with polychlorinated biphenyls (PCB), pesticides, dioxins, furans, and other hazardous organic substances. PCBs are heavy organic liquids once widely used in industry as lubricants, heat transfer oils, and transformer dielectric fluids. In 1976, production was banned when PCBs were recognized as carcinogenic substances. It was estimated that significant quantities (one billion tons) of U.S. soils, including areas on U.S. military bases outside the country, were contaminated by PCB leaks and spills, and cleanup activities began. The BCD technology was developed in response tomore » these activities. This report details the evolution of the process, from inception to deployment in Guam, and describes the process and system components provided to the Navy to meet the remediation requirements. The report is divided into several sections to cover the range of development and demonstration activities. Section 2.0 gives an overview of the project history. Section 3.0 describes the process chemistry and remediation steps involved. Section 4.0 provides a detailed description of each component and specific development activities. Section 5.0 details the testing and deployment operations and provides the results of the individual demonstration campaigns. Section 6.0 gives an economic assessment of the process. Section 7.0 presents the conclusions and recommendations form this project. The appendices contain equipment and instrument lists, equipment drawings, and detailed run and analytical data.« less

Removal of residual contaminants in petroleum-contaminated soil by Fenton-like oxidation.

PubMed

Lu, Mang; Zhang, Zhongzhi; Qiao, Wei; Guan, Yueming; Xiao, Meng; Peng, Chong

2010-07-15

The degradation of bioremediation residues by hydrogen peroxide in petroleum-contaminated soil was investigated at circumneutral pH using a Fenton-like reagent (ferric ion chelated with EDTA). Batch tests were done on 20 g soil suspended in 60 mL aqueous solution containing hydrogen peroxide and Fe(3+)-EDTA complex under constant stirring. A slurry reactor was used to treat the soil based on the optimal reactant conditions. Contaminants were characterized by Fourier transform infrared spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry. The results showed that the optimal treatment condition was: the molar ratio of hydrogen peroxide to iron=200:1, and pH 7.0. Under the optimum condition, total dichloromethane-extractable organics were reduced from 14,800 to 2300 mg kg(-1) soil when the accumulative H(2)O(2) dosage was 2.45 mol kg(-1) soil during the reactor treatment. Abundance of viable cells was lower in incubated Fenton-like treated soil than in untreated soil. Oxidation of contaminants produced remarkable compositional and structural modifications. A fused ring compound, identified as C(34)H(38)N(1), was found to exhibit the greatest resistance to oxidation. 2010 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riha, B.; Looney, B.; Noonkester, J.

Groundwater beneath T-Area, a former laboratory and semiworks operation at the Department of Energy (DOE) Savannah River Site (SRS), is contaminated by chlorinated solvents (cVOCs). Since the contamination was detected in the 1980s, the cVOCs at T-Area have been treated by a combination of soil vapor extraction and groundwater pump and treat. The site received approval to temporarily discontinue the active groundwater treatment and implement a treatability study of enhanced attenuation - an engineering and regulatory strategy that has recently been developed by DOE and the Interstate Technology and Regulatory Council (ITRC 2007). Enhanced attenuation uses active engineering solutions tomore » alter the target site in such a way that the contaminant plume will passively stabilize and shrink and to document that the action will be effective, timely, and sustainable. The paradigm recognizes that attenuation remedies are fundamentally based on a mass balance. Thus, long-term plume dynamics can be altered either by reducing the contaminant loading from the source or by increasing the rate of natural attenuation processes within all, or part of, the plume volume. The combination of technologies that emerged for T-Area included: (1) neat (pure) vegetable oil deployment in the deep vadose zone in the former source area, (2) emulsified vegetable oil deployment within the footprint of the groundwater plume, and (3) identification of attenuation mechanisms and rates for the distal portion of the plume. In the first part, neat oil spreads laterally forming a thin layer on the water table to intercept and reduce future cVOC loading (via partitioning) and reduce oxygen inputs (via biostimulation). In the second and third parts, emulsified oil forms active bioremediation reactor zones within the plume footprint to degrade existing groundwater contamination (via reductive dechlorination and/or cometabolism) and stimulates long-term attenuation capacity in the distal plume (via cometabolism). For TArea, the enhanced attenuation development process proved to be a powerful tool in developing a strategy that provides a high degree of performance while minimizing adverse collateral impacts of the remediation (e.g., energy use and wetland damage) and minimizing life-cycle costs. As depicted in Figure 1, Edible oil deployment results in the development of structured geochemical zones and serves to decrease chlorinated compound concentrations in two ways: (1) physical sequestration, which reduces effective aqueous concentration and mobility; and (2) stimulation of anaerobic, abiotic and cometabolic degradation processes. In the central deployment area, contaminant initially partitions into the added oil phase. Biodegradation of the added organic substrate depletes the aquifer of oxygen and other terminal electron acceptors and creates conditions conducive to anaerobic degradation processes. The organic substrate is fermented to produce hydrogen, which is used as an electron donor for anaerobic dechlorination by organisms such as Dehalococcoides. Daughter products leaving the central treatment zone are amenable to aerobic oxidation. Further, the organic compounds leaving the central deployment zone (e.g., methane and propane) stimulate and enhance down gradient aerobic cometabolism which degrades both daughter compounds and several parent cVOCs. Figure 1 depicts TCE concentration reduction processes (labeled in green) along with their corresponding breakdown products in a structured geochemical zone scenario. A consortium of bacteria with the same net effect of Dehalococcoides may be present in the structured geochemical zones leading to the degradation of TCE and daughter products. Figure 2 shows a schematic of the documented cVOC degradation processes in both the anaerobic and aerobic structured geochemical zones. Specific aerobic and anaerobic bacteria and their degradation pathways are also listed in the diagram and have either been confirmed in the field or the laboratory. See references in the bibliography in Section 11.« less

Evaluation of pulsed corona discharge plasma for the treatment of petroleum-contaminated soil.

PubMed

Li, Rui; Liu, Yanan; Mu, Ruiwen; Cheng, Wenyan; Ognier, Stéphanie

2017-01-01

Petroleum hydrocarbons released to the environment caused by leakage or illegal dumping pose a threat to human health and the natural environment. In this study, the potential of a pulsed corona discharge plasma system for treating petroleum-polluted soils was evaluated. This system removed 76.93 % of the petroleum from the soil in 60 min with an energy efficiency of 0.20 mg/kJ. Furthermore, the energy and degradation efficiencies for the remediation of soil contaminated by single polyaromatic hydrocarbons, such as phenanthrene and pyrene, were also compared, and the results showed that this technology had potential in organic-polluted soil remediation. In addition, the role of water molecules was investigated for their direct involvement in the formation and transportation of active species. The increase of soil moisture to a certain extent clearly benefitted degradation efficiency. Then, treated soils were analyzed by FTIR and GC-MS for proposing the degradation mechanism of petroleum. During the plasma discharging processes, the change of functional group and the detection of small aromatic hydrocarbons indicated that the plasma active species attached petroleum hydrocarbons and degradation occurred. This technique reported herein demonstrated significant potential for the remediation of heavily petroleum-polluted soil, as well as for the treatment of organic-polluted soils.

Innovative Self-Cleaning and Biocompatible Polyester Textiles Nano-Decorated with Fe–N-Doped Titanium Dioxide

PubMed Central

Nica, Ionela Cristina; Stan, Miruna Silvia; Dinischiotu, Anca; Popa, Marcela; Chifiriuc, Mariana Carmen; Lazar, Veronica; Pircalabioru, Gratiela G.; Bezirtzoglou, Eugenia; Iordache, Ovidiu G.; Varzaru, Elena; Dumitrescu, Iuliana; Feder, Marcel; Vasiliu, Florin; Mercioniu, Ionel; Diamandescu, Lucian

2016-01-01

The development of innovative technologies to modify natural textiles holds an important impact for medical applications, including the prevention of contamination with microorganisms, particularly in the hospital environment. In our study, Fe and N co-doped TiO2 nanoparticles have been obtained via the hydrothermal route, at moderate temperature, followed by short thermal annealing at 400 °C. These particles were used to impregnate polyester (PES) materials which have been evaluated for their morphology, photocatalytic performance, antimicrobial activity against bacterial reference strains, and in vitro biocompatibility on human skin fibroblasts. Microscopic examination and quantitative assays have been used to evaluate the cellular morphology and viability, cell membrane integrity, and inflammatory response. All treated PES materials specifically inhibited the growth of Gram-negative bacilli strains after 15 min of contact, being particularly active against Pseudomonas aeruginosa. PES fabrics treated with photocatalysts did not affect cell membrane integrity nor induce inflammatory processes, proving good biocompatibility. These results demonstrate that the treatment of PES materials with TiO2-1% Fe–N particles could provide novel biocompatible fabrics with short term protection against microbial colonization, demonstrating their potential for the development of innovative textiles that could be used in biomedical applications for preventing patients’ accidental contamination with microorganisms from the hospital environment. PMID:28335342

Presence of faecal coliforms and selected heavy metals in ice cubes from food outlets in Taman Universiti, Johor Bahru, Malaysia.

PubMed

Mahat, N A; Meor Ahmad, Z; Abdul Wahab, R

2015-09-01

Consumption of iced beverages is common in Malaysia although specific research focusing on its safety parameters such as presence of faecal coliforms and heavy metal elements remains scarce. A study conducted in Kelantan indicated that faecal coliforms were detected in the majority of the ice cube samples analyzed, largely attributable to improper handling. Hence, it was found pertinent to conduct similar study in other parts of the country such as Johor Bahru if the similar pattern prevailed. Therefore, this present cross sectional study which randomly sampled ice cubes from 30 permanent food outlets in Taman Universiti, Johor Bahru for detecting contamination by faecal coliforms and selected heavy metal elements (lead, copper, manganese and zinc) acquires significance. Faecal coliforms were detected in 11 (36.67%) of the samples, ranging between 1 CFU/100 mL to > 50 CFU/100 mL; two of the samples were grossly contaminated (>50 CFU/100 mL). Interestingly, while positive detection of lead was observed in 29 of the 30 ice cube samples (mean: 0.511±0.105 ppm; range: 0.489-0.674 ppm), copper, manganese and zinc were not detected. In addition, analysis on commercially bottled mineral water as well as in tap water samples did not detect such contaminations. Therefore, it appears that (1) contamination of faecal coliforms in ice cubes in food outlets in Malaysia may not be sporadic in pattern but rather prevalent and (2) the source of water used for manufacturing the ice cubes that contained significant amount of lead would suggest that (3) it was neither originated from the treated tap water supply nor bottled mineral water or (4) perhaps contaminated during manufacturing process. Further studies exploring the source of water used for manufacturing these ice cubes as well as the handling process among food operators deserve consideration.

Preoperative evaluation of hepatic arterial and portal venous anatomy using the time resolved echo-shared MR angiographic technique in living liver donors.

PubMed

Lee, Min Woo; Lee, Jeong Min; Lee, Jae Young; Kim, Se Hyung; Park, Eun-Ah; Han, Joon Koo; Choi, Jin-Young; Kim, Young Jun; Suh, Kyung-Suk; Choi, Byung Ihn

2007-04-01

The purpose of this study was to determine whether MR angiography utilizing the time resolved echo-shared angiographic technique (TREAT) can provide an effective assessment of the hepatic artery (HA) and portal vein (PV) in living donor candidates. MR angiography (MRA)was performed in 27 patients (23 men and 4 women; mean age, 31 years) by using TREAT. Two blinded radiologists evaluated HA anatomy, origin of segment IV feeding artery and PV anatomy in consensus. Qualitative evaluations of MRA images were performed using the following criteria: (a) overall image quality, (b) presence of artifacts, and (c) degree of venous contamination of the arterial phase. Using intraoperative findings as a standard of reference, the accuracy for the HA anatomy, origin of segment IV feeding artery and PV anatomy on TREAT-MRA were 93% (25/27), 85% (23/27), and 96% (26/27), respectively. Overall image qualities were as follows: excellent (n=22, 81%), good (n=4, 15%), and fair (n=1, 4%). Significant artifacts or venous contamination of the arterial phase images was not noted in any patient. TREAT-MRA can provide a complete evaluation of HA and PV anatomy during preoperative evaluation of living liver donors. Furthermore, it provides a more detailed anatomy of the HA without venous contamination.

Development and evaluation of a real-time fluorescent polymerase chain reaction assay for the detection of bovine contaminates in cattle feed.

PubMed

Rensen, Gabriel; Smith, Wayne; Ruzante, Juliana; Sawyer, Mary; Osburn, Bennie; Cullor, James

2005-01-01

A real-time fluorescent polymerase chain reaction assay for detecting prohibited ruminant materials such as bovine meat and bone meal (BMBM) in cattle feed using primers and FRET probes targeting the ruminant specific mitochondrial cytochrome b gene was developed and evaluated on two different types of cattle feed. Common problems involved with PCR based testing of cattle feed include the presence of high levels of PCR inhibitors and the need for certain pre-sample processing techniques in order to perform DNA extractions. We have developed a pre-sample processing technique for extracting DNA from cattle feed which does not require the feed sample to be ground to a fine powder and utilizes materials that are disposed of between samples, thus, reducing the potential of cross contamination. The DNA extraction method utilizes Whatman FTA card technology, is adaptable to high sample throughput analysis and allows for room temperature storage with established archiving of samples of up to 14 years. The Whatman FTA cards are subsequently treated with RNAse and undergo a Chelex-100 extraction (BioRad, Hercules, CA), thus removing potential PCR inhibitors and eluting the DNA from the FTA card for downstream PCR analysis. The detection limit was evaluated over a period of 30 trials on calf starter mix and heifer starter ration feed samples spiked with known concentrations of BMBM. The PCR detection assay detected 0.05% wt/wt BMBM contamination with 100% sensitivity, 100% specificity, and 100% confidence. Concentrations of 0.005% and 0.001% wt/wt BMBM contamination were also detected in both feed types but with varying levels of confidence.

Human outbreak of Salmonella Typhimurium associated with exposure to locally made chicken jerky pet treats, New Hampshire, 2013.

PubMed

Cavallo, Steffany J; Daly, Elizabeth R; Seiferth, John; Nadeau, Alisha M; Mahoney, Jennifer; Finnigan, Jayne; Wikoff, Peter; Kiebler, Craig A; Simmons, Latoya

2015-05-01

Pet treats and pet food can be contaminated with Salmonella and other pathogens, though they are infrequently implicated as the source of human outbreaks. In 2013, the New Hampshire Department of Health and Human Services investigated a cluster of Salmonella Typhimurium infections associated with contaminated locally made pet treats. Case-patients were interviewed with standardized questionnaires to assess food, animal, and social histories. Laboratory and environmental investigations were conducted, including testing of clinical specimens, implicated product, and environmental swabs. Between June and October 2013, a total of 43 ill persons were identified. Sixteen patients (37%) were hospitalized. Among 43 case-patients interviewed, the proportion exposed to dogs (95%) and pet treats (69%) in the 7 days prior to illness was statistically higher than among participants in a U.S. population-based telephone survey (61%, p<0.0001 and 16%, p<0.0001, respectively). On further interview, 38 (88%) reported exposure to Brand X Chicken Jerky, the maker of Brand X chicken jerky, or the facility in which it was made. Product testing isolated the outbreak strain from four of four Brand X Chicken Jerky samples, including an unopened package purchased at retail, opened packages collected from patient households, and unpackaged jerky obtained from the jerky maker. A site visit revealed inadequate processing of the chicken jerky, bare-hand contact with the finished product prior to packaging, and use of vacuum-sealed packaging, which may have enabled facultative anaerobic bacteria to proliferate. Seven (78%) of nine environmental swabs taken during the site visit also yielded the outbreak strain. Brand X Chicken Jerky was voluntarily recalled on September 9, 2013. Consumers should be made aware of the potential for locally made products to be exempt from regulation and for animals and animal food to carry pathogens that cause human illness, and be educated to perform hand hygiene after handling pet food or treats.

Anxiety-like behaviour in mice exposed to tannery wastewater: The effect of photoelectrooxidation treatment.

PubMed

Siqueira, Ionara Rodrigues; Vanzella, Cláudia; Bianchetti, Paula; Rodrigues, Marco Antonio Siqueira; Stülp, Simone

2011-01-01

The leather industry is a major producer of wastewaters and releases large quantities of many different chemical agents used in hide processing into the environment. Since the central nervous system is sensitive to many different contaminants, our aim was to investigate the neurobehavioral effects of exposure of mice to tannery effluents using animal models of depression and anxiety, namely forced swim and elevated plus-maze. In order to propose a clean technology for the treatment of this effluent, we also investigated the exposure of mice to effluents treated by photoelectrooxidation process (PEO). Adult male Swiss albino mice (CF1 strain) were given free access to water bottles containing an effluent treated by a tannery (non-PEO) or PEO-treated tannery wastewater (0.1 and 1% in drinking water). Exposure to tannery wastewater induced behavioural changes in the mice in elevated plus-maze. Exposure to non-PEO 1% decreased the percentage of time spent in the open arms, indicating anxiety-like behaviour. Exposure to tannery wastewater did not alter immobility time in the forced swim test, suggesting that tannery effluents did not induce depression-like behaviour in the mice. These behavioural data suggest that non-PEO tannery effluent has an anxiogenic effect, whereas PEO-treated tannery effluents do not alter anxiety levels. Copyright © 2011 Elsevier Inc. All rights reserved.

In vitro antimicrobial efficacy of MTAD and sodium hypochlorite.

PubMed

Shabahang, Shahrokh; Pouresmail, Manouchehr; Torabinejad, Mahmoud

2003-07-01

The purpose of this study was to compare the ability of a mixture of a tetracycline isomer, an acid, and a detergent (MTAD) with that of sodium hypochlorite (NaOCI) to disinfect human root canals that had been contaminated with whole saliva. One hundred and thirty-two root canals of extracted human teeth were cleaned and shaped using the passive step-back technique and rotary NiTi files. The smear layer was removed, and the teeth were autoclaved. Six autoclaved samples were transferred to sterile broth without contamination with saliva to serve as negative controls. Whole saliva was used to contaminate the root canals of the rest of the samples for 48 h. Six of these contaminated samples were irrigated with Brain Heart Infusion (BHI) broth and served as positive controls. The rest of the contaminated specimens were then divided into two experimental groups of 60 teeth each. In one group, the canals were irrigated with 1 ml MTAD, and the samples were immersed in 2 ml of the same solution for 5 min. In the second group, the specimens were similarly treated with 5.25% NaOCl. All samples were washed in BHI broth and then placed in another tube containing BHI broth and incubated for 96 h. Disinfection of the samples was determined based on presence or absence of turbidity in the broth 96 h later. Twenty-three of 60 teeth treated with NaOCl remained infected. Only one of 60 teeth treated with MTAD remained infected. Statistical analysis of the data using the Chi-square test showed a significant difference between the two groups (p < 0.0001).

Improved radiocarbon analyses of modern human hair to determine the year-of-death by cross-flow nanofiltered amino acids: common contaminants, implications for isotopic analysis, and recommendations.

PubMed

Santos, Guaciara M; De La Torre, Hector A Martinez; Boudin, Mathieu; Bonafini, Marco; Saverwyns, Steven

2015-10-15

In forensic investigation, radiocarbon ((14)C) measurements of human tissues (i.e., nails and hair) can help determine the year-of-death. However, the frequent use of cosmetics can bias hair (14)C results as well as stable isotope values. Evidence shows that hair exogenous impurities percolate beyond the cuticle layer, and therefore conventional pretreatments are ineffective in removing them. We conducted isotopic analysis ((14)C, δ(13)C, δ(15)N and C/N) of conventionally treated and cross-flow nanofiltered amino acid (CFNAA)-treated samples (scalp- and body-hair) from a single female subject using fingernails as a reference. The subject studied frequently applies a permanent dark-brown dye kit to her scalp-hair and uses other care products for daily cleansing. We also performed pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analyses of CFNAA-treated scalp-hair to identify contaminant remnants that could possibly interfere with isotopic analyses. The conventionally treated scalp- and body-hair showed (14)C offsets of ~21‰ and ~9‰, respectively. These offsets confirm the contamination by petrochemicals in modern human hair. A single CFNAA extraction reduced those offsets by ~34%. No significant improvement was observed when sequential extractions were performed, as it appears that the procedure introduced some foreign contaminants. A chromatogram of the CFNAA scalp-hair pyrolysis products showed the presence of petroleum and plant/animal compound residues, which can bias isotopic analyses. We have demonstrated that CFNAA extractions can partially remove cosmetic contaminants embedded in human hair. We conclude that fingernails are still the best source of keratin protein for year-of-death determinations and isotopic analysis, with body-hair and/or scalp-hair coupled with CFNAA extraction a close second. Copyright © 2015 John Wiley & Sons, Ltd.

SUPERFUND TREATABILITY CLEARINGHOUSE: INCINERATION TEST OF EXPLOSIVES CONTAMINATED SOILS AT SAVANNA ARMY DEPOT ACTIVITY, SAVANNA, ILLINOIS

EPA Science Inventory

The primary objective of these tests was to demonstrate the effectiveness of incineration as a decontamination method for explosives contaminated sails. A pilot-scale rotary kiln incinerator, manufactured by ThermAll, Inc., was used to treat both sandy and clayey...

TREATED WASTEWATER AS A SOURCE OF SEDIMENT CONTAMINATION IN GULF OF MEXICO NEAR-COASTAL AREAS

EPA Science Inventory

The primary objective of this baseline survey was to provide some needed perspective on the magnitude of sediment contamination associated with wastewater outfalls discharged to Gulf of Mexico near-coastal areas. The chemical quality and toxicities of whole sediments and pore wa...

TAILORING CATALYSTS FOR HYDRODECHLORINATING CHLORINATED HYDROCARBON CONTAMINANTS IN GROUNDWATER. (R825689C078)

EPA Science Inventory

Abstract

A palladium-on-zeolite catalyst has been optimized for treating groundwater contaminated with halogenated hydrocarbon compounds (HHCs) by hydrodechlorination with dissolved hydrogen. Aqueous sulfite was used as the model poison and the dechlorination of 1,2-di...

TAILORING CATALYSTS FOR HYDRODECHLORINATING CHLORINATED HYDROCARBON CONTAMINANTS IN GROUNDWATER. (R825689C093)

EPA Science Inventory

Abstract

A palladium-on-zeolite catalyst has been optimized for treating groundwater contaminated with halogenated hydrocarbon compounds (HHCs) by hydrodechlorination with dissolved hydrogen. Aqueous sulfite was used as the model poison and the dechlorination of 1,2-di...

Mitigating Impacts Of Arsenic Contaminated Materials Via Two (2) Stabilization Methods Based On Polymeric And Cement Binders

EPA Science Inventory

The primary objective of this study was to evaluate the performance of two selected chemical stabilization and solidification (S/S) techniques to treat three types of arsenic-contaminated wastes 1) chromated copper arsenate (CCA) wood treater waste, 2) La Trinidad Mine tailings, ...

ECONOMICS ANALYSIS OF THE IMPLEMENTATION OF PERMEABLE REACTIVE BARRIERS FOR REMEDIATION OF CONTAMINATED GROUND WATER

EPA Science Inventory

This report presents an analysis of the cost of using permeable reactive barriers to remediate contaminated ground water. When possible, these costs are compared with the cost of pump-and-treat technology for similar situations. Permeable reactive barriers are no longer perceiv...

DEMONSTRATION BULLETIN: IN-SITU STEAM/HOT AIR SOIL STRIPPING TOXIC TREATMENT (USA) INC.

EPA Science Inventory

This technology uses steam and hot air to strip volatile organics from contaminated soil. The treatment equipment is mobile and treats the soil in-situ without need for soil excavation or transportation. The organic contaminants volatilized from the soil are condensed and col...

Environmental contaminant mixtures modulate in vitro influenza infection.

PubMed

Desforges, Jean-Pierre; Bandoro, Christopher; Shehata, Laila; Sonne, Christian; Dietz, Rune; Puryear, Wendy B; Runstadler, Jonathan A

2018-09-01

Environmental chemicals, particularly organochlorinated contaminants (OCs), are associated with a ranged of adverse health effects, including impairment of the immune system and antiviral immunity. Influenza A virus (IAV) is an infectious disease of major global public health concern and exposure to OCs can increase the susceptibility, morbidity, and mortality to disease. It is however unclear how pollutants are interacting and affecting the outcome of viral infections at the cellular level. In this study, we investigated the effects of a mixture of environmentally relevant OCs on IAV infectivity upon in vitro exposure in Madin Darby Canine Kidney (MDCK) cells and human lung epithelial cells (A549). Exposure to OCs reduced IAV infectivity in MDCK and A549 cells during both short (18-24h) and long-term (72h) infections at 0.05 and 0.5ppm, and effects were more pronounced in cells co-treated with OCs and IAV than pre-treated with OCs prior to IAV (p<0.001). Pre-treatment of host cells with OCs did not affect IAV cell surface attachment or entry. Visualization of IAV by transmission electron microscopy revealed increased envelope deformations and fewer intact virions during OC exposure. Taken together, our results suggest that disruption of IAV infection upon in vitro exposure to OCs was not due to host-cell effects influencing viral attachment and entry, but perhaps mediated by direct effects on viral particles or cellular processes involved in host-virus interactions. In vitro infectivity studies such as ours can shed light on the complex processes underlying host-pathogen-pollutant interactions. Copyright © 2018 Elsevier B.V. All rights reserved.

Assessing the Impact of Source-Zone Remediation Efforts at the Contaminant-Plume Scale Through Analysis of Contaminant Mass Discharge

PubMed Central

Brusseau, M. L.; Hatton, J.; DiGuiseppi, W.

2011-01-01

The long-term impact of source-zone remediation efforts was assessed for a large site contaminated by trichloroethene. The impact of the remediation efforts (soil vapor extraction and in-situ chemical oxidation) was assessed through analysis of plume-scale contaminant mass discharge, which was measured using a high-resolution data set obtained from 23 years of operation of a large pump-and-treat system. The initial contaminant mass discharge peaked at approximately 7 kg/d, and then declined to approximately 2 kg/d. This latter value was sustained for several years prior to the initiation of source-zone remediation efforts. The contaminant mass discharge in 2010, measured several years after completion of the two source-zone remediation actions, was approximately 0.2 kg/d, which is ten times lower than the value prior to source-zone remediation. The time-continuous contaminant mass discharge data can be used to evaluate the impact of the source-zone remediation efforts on reducing the time required to operate the pump-and-treat system, and to estimate the cost savings associated with the decreased operational period. While significant reductions have been achieved, it is evident that the remediation efforts have not completely eliminated contaminant mass discharge and associated risk. Remaining contaminant mass contributing to the current mass discharge is hypothesized to comprise poorly-accessible mass in the source zones, as well as aqueous (and sorbed) mass present in the extensive lower-permeability units located within and adjacent to the contaminant plume. The fate of these sources is an issue of critical import to the remediation of chlorinated-solvent contaminated sites, and development of methods to address these sources will be required to achieve successful long-term management of such sites and to ultimately transition them to closure. PMID:22115080

Simultaneous determination of 14 disinfection by-products in meat products using microwave-assisted extraction and static headspace coupled to gas chromatography-mass spectrometry.

PubMed

Cardador, Maria Jose; Gallego, Mercedes

2017-08-04

This paper described the first analytical method to simultaneously determine 14 disinfection by-products (DBPs) in meat products using microwave-assisted extraction (MAE) and static headspace (SHS) followed by gas chromatography-mass spectrometry (GC-MS). The DBPs included were 4 trihalomethanes, 7 haloacetic acids, 2 haloacetonitriles and trichloronitromethane, which are commonly formed as a consequence of the disinfection process of water. The combination of the MAE and SHS techniques allows meat samples to be analysed in two sequential steps into the same HS vial in spite of the sample's complexity. Detection limits were obtained within the range of 0.06-0.70ng/g, and the average relative standard deviation was 7.4%. Recoveries throughout the whole process were between 86 and 95%. The SHS-GC-MS method was applied to determine DBPs in meat products with different industrial processing which could be contaminated through contact with disinfectants and/or treated water employed in the factory either for washing or for the cooking of meat. Up to 5 DBPs were found at ng/g levels in about 36% of the samples analysed, cooked ham being the most contaminated meat product because of the brine solutions employed in its manufacturing process. Copyright © 2017 Elsevier B.V. All rights reserved.

Process wastewater treatability study for Westinghouse fluidized-bed coal gasification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winton, S.L.; Buvinger, B.J.; Evans, J.M.

1983-11-01

In the development of a synthetic fuels facility, water usage and wastewater treatment are major areas of concern. Coal gasification processes generally produce relatively large volumes of gas condensates. These wastewaters are typically composed of a variety of suspended and dissolved organic and inorganic solids and dissolved gaseous contaminants. Fluidized-bed coal gasification (FBG) processes are no exception to this rule. The Department of Energy's Morgantown Energy Technology Center (METC), the Gas Research Institute (GRI), and the Environmental Protection Agency (EPA/IERLRTP) recognized the need for a FBG treatment program to provide process design data for FBG wastewaters during the environmental, health,more » and safety characterization of the Westinghouse Process Development Unit (PDU). In response to this need, METC developed conceptual designs and a program plan to obtain process design and performance data for treating wastewater from commercial-scale Westinghouse-based synfuels plants. As a result of this plan, METC, GRI, and EPA entered into a joint program to develop performance data, design parameters, conceptual designs, and cost estimates for treating wastewaters from a FBG plant. Wastewater from the Westinghouse PDU consists of process quench and gas cooling condensates which are similar to those produced by other FBG processes such as U-Gas, and entrained-bed gasification processes such as Texaco. Therefore, wastewater from this facility was selected as the basis for this study. This paper outlines the current program for developing process design and cost data for the treatment of these wastewaters.« less

Modelling of Remediation Technologies at the Performance Assessment Level

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parton, N.J.; Paksy, A.; Eden, L.

2008-07-01

This paper presents approaches to modelling three different remediation technologies that are designed to support site operators during their assessment of remediation options for the management of radioactively contaminated land on nuclear licensed sites in the UK. The three selected technologies were soil washing, permeable reactive barrier and in-situ stabilisation. The potential exists to represent electrokinetics in the future. These technologies were chosen because it was considered that enough information already existed for site operators to assess mature technologies such as soil dig and disposal and groundwater pump and treat. Using the software code GoldSim, the models have been designedmore » to allow site operators to make both a reasonable scoping level assessment of the viability of treatment and understand the cost-benefits of each technology. For soil washing, a standard soil leaching technique was simulated whereby the soil is separated into fines and oversize particles, and subsequently a chemical reagent is used to strip contamination off the soil. The cost benefit of this technology in terms of capital costs for the plant and materials, operational costs and waste disposal costs can also be assessed. The permeable reactive barrier (PRB) model can represent either a continuous wall or a funnel and gate system. The model simulates the transport of contaminants through the reactive material contained in the PRB. The outputs from the model include concentration of contaminants in the groundwater flow downstream of the PRB, mass of contaminants retained by the PRB, total mass and volume of waste and the various costs associated with the PRB remediation technology. The in-situ stabilisation (ISS) model has the capability to represent remediation by the addition of reagents that immobilise contaminated soil. The model simulates the release of contaminants from the treated soil over time. Performance is evaluated by comparison of the mass of contaminants retained and released to the area outside the treatment zone. Other outputs include amount of spoil generated (to be treated as waste) and the costs associated with the application of the ISS technology. These models are aimed to help users select a technology or technologies that are potentially suitable for a particular site. It is anticipated that they will prompt the user to undertake more detailed assessments to tailor the selected technology to their site specific circumstances and contaminated land conditions. (author)« less

Impact of S fertilizers on pore-water Cu dynamics and transformation in a contaminated paddy soil with various flooding periods.

PubMed

Yang, Jianjun; Zhu, Shenhai; Zheng, Cuiqing; Sun, Lijuan; Liu, Jin; Shi, Jiyan

2015-04-09

Impact of S fertilization on Cu mobility and transformation in contaminated paddy soils has been little reported. In this study, we investigated the dynamics and transformation of dissolved and colloidal Cu in the pore water of a contaminated paddy soil after applying ammonium sulphate (AS) and sulfur coated urea (SCU) with various flooding periods (1, 7 and 60 days). Compared to the control soil, the AS-treated soil released more colloidal and dissolved Cu over the entire flooding period, while the SCU-treated soil had lower colloidal Cu after 7-day flooding but higher colloidal and dissolved Cu after 60-day flooding. Microscopic X-ray fluorescence (μ-XRF) analysis found a close relationship between Fe and Cu distribution on soil colloids after 60-day flooding, implying the formation of colloidal Fe/Cu sulphide coprecipitates. Cu K-edge X-ray absorption near-edge structure (XANES) spectroscopy directly revealed the transformation of outer-sphere complexed Cu(II) species to Cu(II) sulphide and reduced Cu2O in the colloids of S-treated soils after 60-day flooding. These results demonstrated the great influence of S fertilization on pore-water Cu mobility by forming Cu sulphide under flooding conditions, which facilitated our understanding and control of Cu loss in contaminated paddy soils under S fertilization. Copyright © 2015 Elsevier B.V. All rights reserved.

Human Health Screening and Public Health Significance of ...

EPA Pesticide Factsheets

The source water and treated drinking water from twenty five drinking water treatment plants (DWTPs) across the United States were sampled in 2010 – 2012. Samples were analyzed for 247 contaminants using 15 chemical and microbiological methods. Most of these contaminants are not regulated currently either in drinking water or in discharges to ambient water by the United States Environmental Protection Agency (EPA) or other U.S. regulatory agencies. This analysis shows that there is little public health concern for most of the contaminants detected in treated water from the 25 DWTPs participating in this study. For vanadium, the calculated MOE was less than the screening MOE in two DWTPs. Additional study, for example a national survey may be needed to determine the number of people ingesting vanadium above a level of concern. In addition, the concentrations of lithium found in treated water from several DWTPs are within the range previous research has suggested to have a human health effect. Additional investigation of this issue may also be appropriate. Finally, new toxicological data suggests that exposure to manganese at levels in public water supplies may present a public health concern which may warrant a more robust assessment of this information. This paper provides a screening-level human health risk assessment using the margin of exposure of exposure approach, of contaminants of emerging concern detected in drinking water. As far as we are a

The performance of blended conventional and novel binders in the in-situ stabilisation/solidification of a contaminated site soil.

PubMed

Wang, Fei; Wang, Hailing; Jin, Fei; Al-Tabbaa, Abir

2015-03-21

This paper presents an investigation of the effects of novel binders and pH values on the effectiveness of the in-situ stabilisation/solidification technique in treating heavy metals and organic contaminated soils after 1.5-year treatment. To evaluate the performance of different binders, made ground soils of SMiRT site, upto 5 m depth, were stabilised/solidified with the triple auger system and cores were taken for laboratory testing after treatment. Twenty four different binders were used including Portland cement (PC), ground granulated blastfurnace slag (GGBS), pulverised fuel ash (PFA), MgO and zeolite. Unconfined compressive strength (UCS), leachate pH and the leachability of heavy metals and total organics were applied to study the behaviours of binders in treating site soils. Under various contaminant level and binder level, the results show that UCS values were 22-3476 kPa, the leachability of the total organics was in the range of 22-241 mg/l and the heavy metals was in the range of 0.002-0.225 mg/l. In addition, the combination of GGBS and MgO at a ratio of 9:1 shows better immobilisation efficiency in treating heavy metals and organic contaminated soils after 1.5-year treatment, and the binding mechanisms under different binders were also discussed in this paper. Copyright © 2014 Elsevier B.V. All rights reserved.

Remediation of lead-contaminated sediment by biochar-supported nano-chlorapatite: Accompanied with the change of available phosphorus and organic matters.

PubMed

Huang, Danlian; Deng, Rui; Wan, Jia; Zeng, Guangming; Xue, Wenjing; Wen, Xiaofeng; Zhou, Chengyun; Hu, Liang; Liu, Xigui; Xu, Piao; Guo, Xueying; Ren, Xiaoya

2018-04-15

Some rivers in China have been seriously contaminated due to the discharge of lead (Pb) smelting wastewater. In this study, biochar-supported nano-chlorapatite (BC-nClAP) was synthesized to immobilize Pb in contaminated sediment. The remediation effect of BC-nClAP on Pb-contaminated sediment was evaluated through batch experiments and the materials were characterized by x-ray diffraction, scanning electron microscope, Brunner-Emmet-Teller and electronic differential system. It was found that BC-nClAP can transform Pb effectively from labile fraction into stable fraction with a maximum transformation efficiency increasing to 94.1% after 30 days of treatment, and the stabilization efficiency of toxicity characteristic leaching procedure reached 100% only after 16 days of treatment. The content of available phosphorus (AP) in the sediments treated by BC-nClAP was much less than that treated by nClAP, which indicated a lower risk of eutrophication and suggested the dissolution-precipitation mechanism involved in Pb immobilization. BC-nClAP presented the best immobilization efficiency of Pb and the content of organic matters in BC-nClAP treated samples increased the most, thus the OM might play an important role during the Pb immobilization. Copyright © 2018 Elsevier B.V. All rights reserved.

Human health screening and public health significance of contaminants of emerging concern detected in public water supplies

USGS Publications Warehouse

Benson, Robert; Conerly, Octavia D.; Sander, William; Batt, Angela L.; Boone, J. Scott; Furlong, Edward T.; Glassmeyer, Susan T.; Kolpin, Dana W.; Mash, Heath

2017-01-01

The source water and treated drinking water from twenty five drinking water treatment plants (DWTPs) across the United States were sampled in 2010–2012. Samples were analyzed for 247 contaminants using 15 chemical and microbiological methods. Most of these contaminants are not regulated currently either in drinking water or in discharges to ambient water by the U. S. Environmental Protection Agency (USEPA) or other U.S. regulatory agencies. This analysis shows that there is little public health concern for most of the contaminants detected in treated water from the 25 DWTPs participating in this study. For vanadium, the calculated Margin of Exposure (MOE) was less than the screening MOE in two DWTPs. For silicon, the calculated MOE was less than the screening MOE in one DWTP. Additional study, for example a national survey may be needed to determine the number of people ingesting vanadium and silicon above a level of concern. In addition, the concentrations of lithium found in treated water from several DWTPs are within the range previous research has suggested to have a human health effect. Additional investigation of this issue is necessary. Finally, new toxicological data suggest that exposure to manganese at levels in public water supplies may present a public health concern which will require a robust assessment of this information.

Degradation of landfill leachate compounds by persulfate for groundwater remediation

PubMed Central

Zhong, Hua; Tian, Yaling; Yang, Qi; Brusseau, Mark L; Yang, Lei; Zeng, Guangming

2016-01-01

In this study, batch and column experiments were conducted to evaluate the feasibility of using persulfate oxidation to treat groundwater contaminated by landfill leachate (CGW). In batch experiments, persulfate was compared with H2O2, and permanganate for oxidation of organic compounds in CGW. It was also compared with the potential of biodegradation for contaminant removal from CGW. Persulfate was observed to be superior to H2O2 and permanganate for degradation of total organic carbon (TOC) in the CGW. Conversely, biodegradation caused only partial removal of TOC in CGW. In contrast, persulfate caused complete degradation of the TOC in the CGW or aged CGW, showing no selectivity limitation to the contaminants. Magnetite (Fe3O4) enhanced degradation of leachate compounds in both CGW and aged CGW with limited increase in persulfate consumption and sulfate production. Under dynamic flow condition in 1-D column experiments, both biodegradation and persulfate oxidation of TOC were enhanced by Fe3O4. The enhancement, however, was significantly greater for persulfate oxidation. In both batch and column experiments, Fe3O4 by itself caused minimal consumption of persulfate and production of sulfate, indicating that magnetite is a good persulfate activator for treating CGW in heterogeneous systems The results of the study show that the persulfate-based in-situ chemical oxidation (ISCO) method has great potential to treat the groundwater contaminated by landfill leachate. PMID:28584519

Human health screening and public health significance of contaminants of emerging concern detected in public water supplies.

PubMed

Benson, Robert; Conerly, Octavia D; Sander, William; Batt, Angela L; Boone, J Scott; Furlong, Edward T; Glassmeyer, Susan T; Kolpin, Dana W; Mash, Heath E; Schenck, Kathleen M; Simmons, Jane Ellen

2017-02-01

The source water and treated drinking water from twenty five drinking water treatment plants (DWTPs) across the United States were sampled in 2010-2012. Samples were analyzed for 247 contaminants using 15 chemical and microbiological methods. Most of these contaminants are not regulated currently either in drinking water or in discharges to ambient water by the U. S. Environmental Protection Agency (USEPA) or other U.S. regulatory agencies. This analysis shows that there is little public health concern for most of the contaminants detected in treated water from the 25 DWTPs participating in this study. For vanadium, the calculated Margin of Exposure (MOE) was less than the screening MOE in two DWTPs. For silicon, the calculated MOE was less than the screening MOE in one DWTP. Additional study, for example a national survey may be needed to determine the number of people ingesting vanadium and silicon above a level of concern. In addition, the concentrations of lithium found in treated water from several DWTPs are within the range previous research has suggested to have a human health effect. Additional investigation of this issue is necessary. Finally, new toxicological data suggest that exposure to manganese at levels in public water supplies may present a public health concern which will require a robust assessment of this information. Published by Elsevier B.V.

The effect of unresolved contaminant stars on the cross-matching of photometric catalogues

NASA Astrophysics Data System (ADS)

Wilson, Tom J.; Naylor, Tim

2017-07-01

A fundamental process in astrophysics is the matching of two photometric catalogues. It is crucial that the correct objects be paired, and that their photometry does not suffer from any spurious additional flux. We compare the positions of sources in Wide-field Infrared Survey Explorer (WISE), INT Photometric H α Survey, Two Micron All Sky Survey and AAVSO Photometric All Sky Survey with Gaia Data Release 1 astrometric positions. We find that the separations are described by a combination of a Gaussian distribution, wider than naively assumed based on their quoted uncertainties, and a large wing, which some authors ascribe to proper motions. We show that this is caused by flux contamination from blended stars not treated separately. We provide linear fits between the quoted Gaussian uncertainty and the core fit to the separation distributions. We show that at least one in three of the stars in the faint half of a given catalogue will suffer from flux contamination above the 1 per cent level when the density of catalogue objects per point spread function area is above approximately 0.005. This has important implications for the creation of composite catalogues. It is important for any closest neighbour matches as there will be a given fraction of matches that are flux contaminated, while some matches will be missed due to significant astrometric perturbation by faint contaminants. In the case of probability-based matching, this contamination affects the probability density function of matches as a function of distance. This effect results in up to 50 per cent fewer counterparts being returned as matches, assuming Gaussian astrometric uncertainties for WISE-Gaia matching in crowded Galactic plane regions, compared with a closest neighbour match.

The Exploration Water Recovery System

NASA Technical Reports Server (NTRS)

ORourke, Mary Jane E.; Carter, Layne; Holder, Donald W.; Tomes, Kristin M.

2006-01-01

The Exploration Water Recovery System is designed towards fulfillment of NASA s Vision for Space Exploration, which will require elevation of existing technologies to higher levels of optimization. This new system, designed for application to the Exploration infrastructure, presents a novel combination of proven air and water purification technologies. The integration of unit operations is modified from that of the current state-of-the-art water recovery system so as to optimize treatment of the various waste water streams, contaminant loads, and flow rates. Optimization is achieved primarily through the removal of volatile organic contaminants from the vapor phase prior to their absorption into the liquid phase. In the current state-of-the-art system, the water vapor in the cabin atmosphere is condensed, and the volatile organic contaminants present in that atmosphere are absorbed into the aqueous phase. Removal of contaminants the5 occurs via catalytic oxidation in the liquid phase. Oxidation kinetics, however, dictate that removal of volatile organic contaminants from the vapor phase can inherently be more efficient than their removal from the aqueous phase. Taking advantage of this efficiency reduces the complexity of the water recovery system. This reduction in system complexity is accompanied by reductions in the weight, volume, power, and resupply requirements of the system. Vapor compression distillation technology is used to treat the urine, condensate, and hygiene waste streams. This contributes to the reduction in resupply, as incorporation of vapor compression distillation technology at this point in the process reduces reliance on the expendable ion exchange and adsorption media used in the current state-of-the-art water recovery system. Other proven technologies that are incorporated into the Exploration Water Recovery System include the Trace Contaminant Control System and the Volatile Removal Assembly.

Natural attenuation software (NAS): Assessing remedial strategies and estimating timeframes

USGS Publications Warehouse

Mendez, E.; Widdowson, M.; Chapelle, F.; Casey, C.

2005-01-01

Natural Attenuation Software (NAS) is a screening tool to estimate remediation timeframes for monitored natural attenuation (MNA) and to assist in decision-making on the level of source zone treatment in conjunction with MNA using site-specific remediation objectives. Natural attenuation processes that NAS models include are advection, dispersion, sorption, non-aqueous phase liquid (NAPL) dissolution, and biodegradation of either petroleum hydrocarbons or chlorinated ethylenes. Newly-implemented enhancements to NAS designed to maximize the utility of NAS for site managers were observed. NAS has expanded source contaminant specification options to include chlorinated ethanes and chlorinated methanes, and to allow for the analysis of any other user-defined contaminants that may be subject to microbially-mediated transformations (heavy metals, radioisotopes, etc.). Included is the capability to model co-mingled plumes, with constituents from multiple contaminant categories. To enable comparison of remediation timeframe estimates between MNA and specific engineered remedial actions , NAS was modified to incorporate an estimation technique for timeframes associated with pump-and-treat remediation technology for comparison to MNA. This is an abstract of a paper presented at the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

Effectiveness of a spontaneous carvacrol nanoemulsion against Salmonella enterica Enteritidis and Escherichia coli O157:H7 on contaminated broccoli and radish seeds.

PubMed

Landry, Kyle S; Micheli, Sean; McClements, David Julian; McLandsborough, Lynne

2015-10-01

The incidence of foodborne illness associated with the consumption of fresh produce has continued to increase over the past decade. Sprouts, such as mung bean, alfalfa, radish, and broccoli, are minimally processed and have been sources for foodborne illness. Currently, a 20,000 ppm calcium hypochlorite soak is recommended for the treatment of sprouting seeds. In this study, the efficacy of an antimicrobial carvacrol nanoemulsion was tested against Salmonella enterica subspecies enterica serovar Enteritidis (ATCC BAA-1045) or EGFP expressing Escherichia coli O157:H7 (ATCC 42895) contaminated sprouting seeds. Antimicrobial treatments were performed by soaking inoculated seeds in nanoemulsions (4000 or 8000 ppm) for 30 or 60 min. Following treatment, surviving cells were determined by performing plate counts and/or Most Probable Number (MPN) enumeration. Treated seeds were sprouted and tested for the presence of pathogens. Treatment successfully inactivated low levels (2 and 3 log CFU/g) of S. Enteritidis and E. coli on radish seeds when soaked for 60 min at concentrations ≥4000 (0.4%) ppm carvacrol. This treatment method was not affective on contaminated broccoli seeds. Total sprout yield was not influenced by any treatments. These results show that carvacrol nanoemulsions may be an alternative treatment method for contaminated radish seeds. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pore-Scale Transport of Strontium During Dynamic Water Content Changes in the Unsaturated Zone

NASA Astrophysics Data System (ADS)

Weaver, W.; Kibbey, T. C. G.; Papelis, C.

2016-12-01

Dynamic water content changes in the unsaturated zone caused by natural and manmade processes, such as evaporation, rainfall, and irrigation, have an effect on contaminant mobility. In general, in the unsaturated zone, evaporation causes an increase in contaminant concentrations, potentially leading to sorption of contaminants on aquifer materials or precipitation of crystalline or amorphous phases. On the other hand, increase of water content may result in dissolution of precipitated phases and increased mobility of contaminants. The objective of this study was to develop a quantitative model for the transport of strontium through sand under dynamic water content conditions, as a function of strontium concentration, pH, and ionic strength. Strontium was selected as a surrogate for strontium-90, a by-product of nuclear reactions. The dynamic water content was determined using an automated device for rapidly measuring the hysteretic capillary pressure—saturation relationship, followed by ambient air evaporation, and gravimetric water content measurement. Strontium concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS). Flow interruption experiments were conducted to determine whether equilibrium conditions existed for a given flowrate. Scanning electron microscopy (SEM) was used to visualize the treated quartz sand particles and the distribution of strontium on sand grains was determined using elemental maps created by energy-dispersive x-ray spectroscopy (EDX). Strontium behavior appears to be pH dependent as well as ionic strength dependent under these conditions.

Evaluating pharmaceuticals and caffeine as indicators of fecal contamination in drinking water sources of the Greater Montreal region.

PubMed

Daneshvar, Atlasi; Aboulfadl, Khadija; Viglino, Liza; Broséus, Romain; Sauvé, Sébastien; Madoux-Humery, Anne-Sophie; Weyhenmeyer, Gesa A; Prévost, Michèle

2012-06-01

We surveyed four different river systems in the Greater Montreal region, upstream and downstream of entry points of contamination, from April 2007 to January 2009. The studied compounds belong to three different groups: PPCPs (caffeine, carbamazepine, naproxen, gemfibrozil, and trimethoprim), hormones (progesterone, estrone, and estradiol), and triazine herbicides and their metabolites (atrazine, deethylatrazine, deisopropylatrazine, simazine, and cyanazine). In the system A, B, and C having low flow rate and high TOC, we observed the highest detection frequencies and mass flows of PPCPs compared to the other compounds, reflecting discharge of urban contaminations through WWTPs and CSOs. However, in River D, having high flow rate and low TOC, comparable frequency of detection of triazine and their by-products and PPCPs, reflecting cumulative loads of these compounds from the Great Lakes as well as persistency against natural attenuation processes. Considering large differences in the removal efficiencies of caffeine and carbamazepine, a high ratio of caffeine/carbamazepine might be an indicative of a greater proportion of raw sewage versus treated wastewater in surface waters. In addition, caffeine appeared to be a promising indicator of recent urban fecal contaminations, as shown by the significant correlation with FC (R(2)=0.45), while carbamazepine is a good indicator of cumulative persistence compounds. Copyright © 2012 Elsevier Ltd. All rights reserved.

Toxicity induced by F. poae-contaminated feed and the protective effect of Montmorillonite supplementation in broilers.

PubMed

Yang, Lingchen; Zhao, Zhiyong; Deng, Yifeng; Zhou, Zhenlei; Hou, Jiafa

2014-12-01

The T-2 and HT-2 toxins, the main metabolites of Fusarium poae, induce toxicity in broilers and accumulate in tissues. Consequently, during the breeding process of broilers, diets are frequently supplemented with physical adsorbents to protect birds against the toxicity induced by mycotoxins. In the present research, T-2 and HT-2 were produced in maize inoculated with F. poae. Mont, the strongest adsorbent based on in vitro adsorption ratios, was added to the contaminated diet. One-day-old chickens were randomly and equally divided into the following four groups: control diet group, Mont supplemented diet group, contaminated diet group and detoxification diet group. The experiment lasted for 42 days. Compared to the control group, the contaminated group showed significant decrease in body weight, feed intake and TP (P < 0.05), and marked increase in FCR, ALP, AST and ALT activity, T-2/HT-2 residues in the tissues and the relative expressions of apoptosis-related mRNAs (P < 0.05). Mont supplementation provided protection for the treated broilers in terms of performance, blood biochemistry, hepatic function, T-2/HT-2 residue of tissues and apoptosis. Therefore, Mont may be suitable as a detoxification agent for T-2/HT-2 in feed for broilers. Copyright © 2014 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menon, R.; Grames, L.M.

Pilot Carrousel testing was conducted for about three months on wastewaters generated at a major potato processing facility in 1993. The testing focused toward removal of BOD, NH{sub 3} and NO{sub 3}, and Total-P. After five-six weeks that it took for the system to reach steady state operation, the pilot plant was able to treat the wastewaters quite well. Effluent BOD{sub 5} and TKN values were less than 8 and 4 mg/L, respectively, during the second half of testing. Total-P in the effluent was less than 10 mg/L, although this step was not optimized. Based on the pilot testing, amore » full-scale Carrousel activated sludge plant was designed and commissioned in 1994. This plant is currently treating all the wastewaters from the facility and performing contaminant removals at a very high level.« less

Control of natural microorganisms in chamomile (Chamomilla recutita L.) by gamma ray and electron beam irradiation.

PubMed

Al-Bachir, Mahfouz

2017-01-01

Microbial contamination levels and corresponding sensitivities to gamma rays (GR) and elec- tron beam (EB) irradiation were tested in chamomile (Chamomile recutta L.). Chamomile powders were treated with 10 and 20 kGy by GR and EB, respectively. Microbiological and chemical analyses were performed on controls and treated samples immediately after irradiation, and after 12 months of storage. The control samples of chamomile exhibited rather high microbiological contamination, exceeding the levels of 4 log10 CFU g-1   (CFU - colony forming units) reported by national and international authorities as the maximum permissible total count level. Irradiation with GR and EB was found to cause a reduction in microbial contamination proportionate to the dose delivered. The sterilizing effect of EB on microorganisms was higher than the GR one. A dose of 10 kGy of GR and EB significantly (p < 0.05) reduced the total bacte- rial, total coliform and total fungal contamination. A dose of 20 kGy of GR significantly (p < 0.05) reduced the total bacterial and total fungal contamination, while a 20 kGy dose of EB reduced the initial bacterial, total coliform and total fungal contamination to below detection level when the analysis was carried out im- mediately after irradiation treatment or after 12 months of storage. The comparative study demonstrated that electron beam was more effective for decontamination of chamomile powder than gamma irradiation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orth, R.; Dauda, T.; McKenzie, D.E.

Contamination in low-permeability soils poses a significant technical challenge to in-situ remediation efforts. Poor accessibility to the contaminants and difficulty in delivery of treatment reagents have rendered existing in-situ treatments such as bioremediation, vapor extraction, and pump and treat rather ineffective when applied to low permeability soils present at many contaminated sites. The technology is an integrated in-situ treatment in which established geotechnical methods are used to install degradation zones directly in the contaminated soil and electro-osmosis is utilized to move the contaminants back and forth through those zones until the treatment is completed. The present Topical Report for Taskmore » {number_sign}3.3 summarizes the iron dechlorination research conducted by Monsanto Company.« less

Method of cleaning plastics using super and subcritical media

DOEpatents

Sawan, Samuel P.; Spall, W. Dale; Talhi, Abdelhafid

1998-05-26

A method for treating a plastic, such as polyethylene or polypropylene, to remove at least a portion of at least one contaminant includes combining the plastic with a supercritical medium, such as carbon dioxide or sulfur hexafluoride, whereby at least a portion of the contaminant dissolves in the supercritical medium. Alternatively, the plastic can be combined with a suitable liquid medium, such as carbon dioxide or liquid sulfur hexafluoride. At least a portion of the medium, containing the dissolved contaminant, is separated from the plastic, thereby removing at least a portion of the contaminant from the plastic.

Method of cleaning plastics using super and subcritical media

DOEpatents

Sawan, S.P.; Spall, W.D.; Talhi, A.

1998-05-26

A method for treating a plastic, such as polyethylene or polypropylene, to remove at least a portion of at least one contaminant includes combining the plastic with a supercritical medium, such as carbon dioxide or sulfur hexafluoride, whereby at least a portion of the contaminant dissolves in the supercritical medium. Alternatively, the plastic can be combined with a suitable liquid medium, such as carbon dioxide or liquid sulfur hexafluoride. At least a portion of the medium, containing the dissolved contaminant, is separated from the plastic, thereby removing at least a portion of the contaminant from the plastic. 10 figs.

Effects of blood contamination on microtensile bond strength to dentin of three self-etch adhesives.

PubMed

Chang, Seok Woo; Cho, Byeong Hoon; Lim, Ran Yeob; Kyung, Seung Hyun; Park, Dong Sung; Oh, Tae Seok; Yoo, Hyun Mi

2010-01-01

This study evaluated the effects of blood contamination and decontamination methods during different steps of bonding procedures on the microtensile bond strength of two-step self-etch adhesives to dentin. Sixty extracted human molars were ground flat to expose occlusal dentin. The 60 molars were randomly assigned to three groups, each treated with a different two-step self-etch adhesive: Clearfil SE Bond, AdheSE and Tyrian SPE. In turn, these groups were subdivided into five subgroups (n = 20), each treated using different experimental conditions as follows: control group-no contamination; contamination group 1-CG1: primer application/ contamination/primer re-application; contamination group 2-CG2: primer application/contamination/wash/dry/primer re-application; contamination group 3-CG3: primer application/adhesive application/light curing/contamination/ adhesive re-application/light curing; contamina- tion group 4-CG4: primer application/adhesive application/light curing/contamination/wash/ dry/adhesive re-application/light curing. Composite buildup was performed using Z250. After 24 hours of storage in distilled water at 37 degrees C, the bonded specimens were trimmed to an hourglass shape and serially sectioned into slabs with 0.6 mm2 cross-sectional areas. Microtensile bond strengths (MTBS) were assessed for each specimen using a universal testing machine. The data were analyzed by two-way ANOVA followed by a post hoc LSD test. SEM evaluations of the fracture modes were also performed. The contaminated specimens showed lower bond strengths than specimens in the control group (p < 0.05), with the exception of CG1 in the Clearfil SE group and CG2 and CG3 in the Tyrian SPE group. Among the three self-etch adhesives, the Tyrian SPE group exhibited a significantly lower average MTBS compared to the Clearfil SE Bond and AdheSE (p < 0.05) groups. Based on the results of the current study, it was found that blood contamination reduced the MTBS of all three self-etch adhesives to dentin, and water-rinsing was unable to overcome the effects of blood contamination.

Preservative-treated wood and alternative products in the Forest Service

Treesearch

James (Scott) Groenier; Stan Lebow

2006-01-01

When treated wood is used in field settings, the possibility of environmental contamination raises concerns. There is increasing pressure to be environmentally friendly and to reduce, restrict, or eliminate the use of wood preservatives because of the concern that toxic constituents may leach from the treated wood. This report will provide an overview of preservative...

Nationwide reconnaissance of contaminants of emerging concern in source and treated drinking waters of the United States: Pharmaceuticals.

PubMed

Furlong, Edward T; Batt, Angela L; Glassmeyer, Susan T; Noriega, Mary C; Kolpin, Dana W; Mash, Heath; Schenck, Kathleen M

2017-02-01

Mobile and persistent chemicals that are present in urban wastewater, such as pharmaceuticals, may survive on-site or municipal wastewater treatment and post-discharge environmental processes. These pharmaceuticals have the potential to reach surface and groundwaters, essential drinking-water sources. A joint, two-phase U.S. Geological Survey-U.S. Environmental Protection Agency study examined source and treated waters from 25 drinking-water treatment plants from across the United States. Treatment plants that had probable wastewater inputs to their source waters were selected to assess the prevalence of pharmaceuticals in such source waters, and to identify which pharmaceuticals persist through drinking-water treatment. All samples were analyzed for 24 pharmaceuticals in Phase I and for 118 in Phase II. In Phase I, 11 pharmaceuticals were detected in all source-water samples, with a maximum of nine pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was five. Quantifiable pharmaceutical detections were fewer, with a maximum of five pharmaceuticals in any one sample and a median for all samples of two. In Phase II, 47 different pharmaceuticals were detected in all source-water samples, with a maximum of 41 pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was eight. For 37 quantifiable pharmaceuticals in Phase II, median concentrations in source water were below 113ng/L. For both Phase I and Phase II campaigns, substantially fewer pharmaceuticals were detected in treated water samples than in corresponding source-water samples. Seven different pharmaceuticals were detected in all Phase I treated water samples, with a maximum of four detections in any one sample and a median of two pharmaceuticals for all samples. In Phase II a total of 26 different pharmaceuticals were detected in all treated water samples, with a maximum of 20 pharmaceuticals detected in any one sample and a median of 2 pharmaceuticals detected for all 25 samples. Source-water type influences the presence of pharmaceuticals in source and treated water. Treatment processes appear effective in reducing concentrations of most pharmaceuticals. Pharmaceuticals more consistently persisting through treatment include carbamazepine, bupropion, cotinine, metoprolol, and lithium. Pharmaceutical concentrations and compositions from this study provide an important base data set for further sublethal, long-term exposure assessments, and for understanding potential effects of these and other contaminants of emerging concern upon human and ecosystem health. Copyright © 2016. Published by Elsevier B.V.

An evaluation of technologies for the heavy metal remediation of dredged sediments.

PubMed

Mulligan, C N; Yong, R N; Gibbs, B F

2001-07-30

Sediments dewatering is frequently necessary after dredging to remediate and treat contaminants. Methods include draining of the water in lagoons with or without coagulants and flocculants, or using presses or centrifuges. Treatment methods are similar to those used for soil and include pretreatment, physical separation, thermal processes, biological decontamination, stabilization/solidification and washing. However, compared to soil treatment, few remediation techniques have been commercially used for sediments. In this paper, a review of the methods that have been used and an evaluation of developed and developing technologies is made. Sequential extraction technique can be a useful tool for determining metal speciation before and after washing. Solidification/stabilization techniques are successful but significant monitoring is required, since the solidification process can be reversible. In addition, the presence of organics can reduce treatment efficiency. Vitrification is applicable for sediments but expensive. Only if a useful glass product can be sold will this process be economically viable. Thermal processes are only applicable for removal of volatile metals, such as mercury and costs are high. Biological processes are under development and have the potential to be low cost. Since few low cost metal treatment processes for sediments are available, there exists significant demand for further development. Pretreatment may be one of the methods that can reduce costs by reducing the volumes of sediments that need to be treated.

Some ozone advanced oxidation processes to improve the biological removal of selected pharmaceutical contaminants from urban wastewater.

PubMed

Espejo, Azahara; Aguinaco, Almudena; Amat, Ana M; Beltrán, Fernando J

2014-01-01

Removal of nine pharmaceutical compounds--acetaminophen (AAF), antipyrine (ANT), caffeine (CAF), carbamazepine (CRB), diclofenac (DCF), hydrochlorothiazide (HCT), ketorolac (KET), metoprolol (MET) and sulfamethoxazole (SMX)-spiked in a primary sedimentation effluent of a municipal wastewater has been studied with sequential aerobic biological and ozone advanced oxidation systems. Combinations of ozone, UVA black light and Fe(III) or Fe3O4 constituted the chemical systems. During the biological treatment (hydraulic residence time, HRT = 24 h), only AAF and CAF were completely eliminated, MET, SMX and HCT reached partial removal rates and the rest of compounds were completely refractory. With any ozone advanced oxidation process applied, the remaining pharmaceuticals disappear in less than 10 min. Fe3O4 or Fe(III) photocatalytic ozonation leads to 35% mineralization compared to 13% reached during ozonation alone after about 30-min reaction. Also, biodegradability of the treated wastewater increased 50% in the biological process plus another 150% after the ozonation processes. Both untreated and treated wastewater was non-toxic for Daphnia magna (D. magna) except when Fe(III) was used in photocatalytic ozonation. In this case, toxicity was likely due to the ferryoxalate formed in the process. Kinetic information on ozone processes reveals that pharmaceuticals at concentrations they have in urban wastewater are mainly removed through free radical oxidation.

Improved system for floor cleaning in health care facilities.

PubMed Central

Schmidt, E A; Coleman, D L; Mallison, G F

1984-01-01

A new system has been developed for sanitizing floors in hospitals; this system replaces the traditional procedure of daily dusting and wet mopping with a disinfectant-detergent solution and periodic buffing . This new system relies on a sequence of procedures consisting of dust mopping using a chemically treated dust mop, machine buffing of a sprayed-on polymer treatment, and a second dust mopping . The effectiveness of the procedures was evaluated by means of surface sampling for bacterial contamination and air sampling for airborne bacteria and dust. The level of bacterial contamination on the floors was reduced by 93.6% by using the new system, compared with 79.8% by using the conventional process of dust mopping and wet mopping with a disinfectant solution. The levels of airborne bacteria during and after the individual procedures did not vary significantly from the initial level (123.6 CFU/per m3 of air). A survey of representative colonies from air samples revealed staphylococci, gram-positive bacilli, gram-positive diplococci, yeast cells, and infrequent gram-negative rods. The distribution at the conclusion of the sanitizing process was similar to that at the outset. Similarly, the levels of airborne dust measured during and after the individual procedures did not vary significantly from the initial level. When compared with the traditional method of cleaning by wet mopping , the new method was significantly more effective in removal of microbial contamination and required less labor. PMID:6742835

Poplar response to cadmium and lead soil contamination.

PubMed

Radojčić Redovniković, Ivana; De Marco, Alessandra; Proietti, Chiara; Hanousek, Karla; Sedak, Marija; Bilandžić, Nina; Jakovljević, Tamara

2017-10-01

An outdoor pot experiment was designed to study the potential of poplar (Populus nigra 'Italica') in phytoremediation of cadmium (Cd) and lead (Pb). Poplar was treated with a combination of different concentrations of Cd (w = 10, 25, 50mgkg -1 soil) and Pb (400, 800, 1200mgkg -1 soil) and several physiological and biochemical parameters were monitored including the accumulation and distribution of metals in different plant parts (leaf, stem, root). Simultaneously, the changes in the antioxidant system in roots and leaves were monitored to be able to follow synergistic effects of both heavy metals. Moreover, a statistical analysis based on the Random Forests Analysis (RFA) was performed in order to determine the most important predictors affecting growth and antioxidative machinery activities of poplar under heavy metal stress. The study demonstrated that tested poplar could be a good candidate for phytoextraction processes of Cd in moderately contaminated soils, while in heavily contaminated soil it could be only considered as a phytostabilisator. For Pb remediation only phytostabilisation process could be considered. By using RFA we pointed out that it is important to conduct the experiments in an outdoor space and include environmental conditions in order to study more realistic changes of growth parameters and accumulation and distribution of heavy metals. Also, to be able to better understand the interactions among previously mentioned parameters, it is important to conduct the experiments during prolonged time exposure., This is especially important for the long life cycle woody species. Copyright © 2017. Published by Elsevier Inc.

Performance of nanoscale zero-valent iron in nitrate reduction from water using a laboratory-scale continuous-flow system.

PubMed

Khalil, Ahmed M E; Eljamal, Osama; Saha, Bidyut Baran; Matsunaga, Nobuhiro

2018-04-01

Nanoscale zero-valent iron (nZVI) is a versatile treatment reagent that should be utilized in an effective application for nitrate remediation in water. For this purpose, a laboratory-scale continuous-flow system (LSCFS) was developed to evaluate nZVI performance in removal of nitrate in different contaminated-water bodies. The equipment design (reactor, settler, and polisher) and operational parameters of the LSCFS were determined based on nZVI characterization and nitrate reduction kinetics. Ten experimental runs were conducted at different dosages (6, 10 and 20 g) of nZVI-based reagents (nZVI, bimetallic nZVI-Cu, CuCl 2 -added nZVI). Effluent concentrations of nitrogen and iron compounds were measured, and pH and ORP values were monitored. The major role exhibited by the recirculation process of unreacted nZVI from the settler to the reactor succeeded in achieving overall nitrate removal efficiency (RE) of >90%. The similar performance of both nZVI and copper-ions-modified nZVI in contaminated distilled water was an indication of LSCFS reliability in completely utilizing iron nanoparticles. In case of treating contaminated river water and simulated groundwater, the nitrate reduction process was sensitive towards the presence of interfering substances that dropped the overall RE drastically. However, the addition of copper ions during the treatment counteracted the retardation effect and greatly enhanced the nitrate RE. Copyright © 2018 Elsevier Ltd. All rights reserved.

Inactivation of Uropathogenic Escherichia coli in Ground Chicken Meat Using High Pressure Processing and Gamma Radiation, and in Purge and Chicken Meat Surfaces by Ultraviolet Light.

PubMed

Sommers, Christopher H; Scullen, O J; Sheen, Shiowshuh

2016-01-01

Extraintestinal pathogenic Escherichia coli, including uropathogenic E. coli (UPEC), are common contaminants in poultry meat and may cause urinary tract infections after colonization of the gastrointestinal tract and transfer of contaminated feces to the urethra. Three non-thermal processing technologies used to improve the safety and shelf-life of both human and pet foods include high pressure processing (HPP), ionizing (gamma) radiation (GR), and ultraviolet light (UV-C). Multi-isolate cocktails of UPEC were inoculated into ground chicken which was then treated with HPP (4°C, 0-25 min) at 300, 400, or 500 MPa. HPP D10, the processing conditions needed to inactivate 1 log of UPEC, was 30.6, 8.37, and 4.43 min at 300, 400, and 500 MPa, respectively. When the UPEC was inoculated into ground chicken and gamma irradiated (4 and -20°C) the GR D10 were 0.28 and 0.36 kGy, respectively. The UV-C D10 of UPEC in chicken suspended in exudate and placed on stainless steel and plastic food contact surfaces ranged from 11.4 to 12.9 mJ/cm(2). UV-C inactivated ca. 0.6 log of UPEC on chicken breast meat. These results indicate that existing non-thermal processing technologies such as HPP, GR, and UV-C can significantly reduce UPEC levels in poultry meat or exudate and provide safer poultry products for at-risk consumers.