Sample records for tetrachloroethylene

  1. ACUTE TOXICITY OF TETRACHLOROETHYLENE AND TETRACHLOROETHYLENE WITH DIMETHYLFORMAMIDE TO RAINBOW TROUT (SALMO GAIRDNERI)

    EPA Science Inventory

    In this study, two acute toxicity tests were conducted with tetrachloroethylene (TCE) using rainbow trout. DMF was used as an additive in one of the tests and was proportionally diluted with the toxicant. The 96 hr LC50 was 4.99 mg/l in the test without DMF and 5.84 mg/l for DMF ...

  2. Health Assessment Document for Tetrachloroethylene (Perchloroethylene) (Final Report)

    EPA Science Inventory

    Tetrachloroethylene (PCE) is a volatile solvent with important commercial applications. It has been detected in the ambient air of a variety of urban and nonurban areas of the United States. It has less frequently been detected in water but has been monitored generally at levels ...

  3. SURFACTANT ENHANCED REMEDIATION OF SOIL COLUMNS CONTAMINATED BY RESIDUAL TETRACHLOROETHYLENE

    EPA Science Inventory

    The ability of aqueous surfactant solutions to recover tetrachloroethylene (PCE) entrapped in Ottawa sand was evaluated in four column experiments. Residual PCE was emplaced by injecting 14C-labeled PCE into water-saturated soil columns and displacing the free product ...

  4. SURFACTANT ENHANCED REMEDIATION OF SOIL COLUMNS CONTAMINATED BY RESIDUAL TETRACHLOROETHYLENE

    EPA Science Inventory

    The ability of aqueous surfactant solutions to recover tetrachloroethylene (PCE) entrapped in Ottawa and was evaluated in four column experiments. esidual PCE was emplaced by injecting 14 C-labeled PCE into water-saturated soil columns and displacing the free product with water. ...

  5. Surfactant enhanced remediation of soil columns contaminated by residual tetrachloroethylene

    Microsoft Academic Search

    K. D. Pennell; M. Jin; L. M. Abriola; G. A. Pope

    1994-01-01

    The ability of aqueous surfactant solutions to recover tetrachloroethylene (PCE) entrapped in Ottawa sand was evaluated in four column experiments. Residual PCE was emplaced by injecting (14)C-labeled PCE into water-saturated soil columns and displacing the free product with water. Miscible displacement experiments were conducted before and after PCE entrapment to determine the influence or residual PCE on column dispersivities. The

  6. Human Health Effects of Tetrachloroethylene: Key Findings and Scientific Issues

    PubMed Central

    Hogan, Karen A.; Scott, Cheryl Siegel; Cooper, Glinda S.; Bale, Ambuja S.; Kopylev, Leonid; Barone, Stanley; Makris, Susan L.; Glenn, Barbara; Subramaniam, Ravi P.; Gwinn, Maureen R.; Dzubow, Rebecca C.; Chiu, Weihsueh A.

    2014-01-01

    Background: The U.S. Environmental Protection Agency (EPA) completed a toxicological review of tetrachloroethylene (perchloroethylene, PCE) in February 2012 in support of the Integrated Risk Information System (IRIS). Objectives: We reviewed key findings and scientific issues regarding the human health effects of PCE described in the U.S. EPA’s Toxicological Review of Tetrachloroethylene (Perchloroethylene). Methods: The updated assessment of PCE synthesized and characterized a substantial database of epidemiological, experimental animal, and mechanistic studies. Key scientific issues were addressed through modeling of PCE toxicokinetics, synthesis of evidence from neurological studies, and analyses of toxicokinetic, mechanistic, and other factors (tumor latency, severity, and background rate) in interpreting experimental animal cancer findings. Considerations in evaluating epidemiological studies included the quality (e.g., specificity) of the exposure assessment methods and other essential design features, and the potential for alternative explanations for observed associations (e.g., bias or confounding). Discussion: Toxicokinetic modeling aided in characterizing the complex metabolism and multiple metabolites that contribute to PCE toxicity. The exposure assessment approach—a key evaluation factor for epidemiological studies of bladder cancer, non-Hodgkin lymphoma, and multiple myeloma—provided suggestive evidence of carcinogenicity. Bioassay data provided conclusive evidence of carcinogenicity in experimental animals. Neurotoxicity was identified as a sensitive noncancer health effect, occurring at low exposures: a conclusion supported by multiple studies. Evidence was integrated from human, experimental animal, and mechanistic data sets in assessing adverse health effects of PCE. Conclusions: PCE is likely to be carcinogenic to humans. Neurotoxicity is a sensitive adverse health effect of PCE. Citation: Guyton KZ, Hogan KA, Scott CS, Cooper GS, Bale AS, Kopylev L, Barone S Jr, Makris SL, Glenn B, Subramaniam RP, Gwinn MR, Dzubow RC, Chiu WA. 2014. Human health effects of tetrachloroethylene: key findings and scientific issues. Environ Health Perspect 122:325–334;?http://dx.doi.org/10.1289/ehp.1307359 PMID:24531164

  7. Visual contrast sensitivity in children exposed to tetrachloroethylene.

    PubMed

    Storm, Jan E; Mazor, Kimberly A; Aldous, Kenneth M; Blount, Benjamin C; Brodie, Scott E; Serle, Janet B

    2011-01-01

    This study examined relationships between indoor air, breath, and blood tetrachloroethylene (perc) levels and visual contrast sensitivity (VCS) among adult and child residents of buildings with or without a colocated dry cleaner using perc. Decreasing trends in proportions of adults or children with maximum VCS scores indicated decreased VCS at a single spatial frequency (12 cycles per degree [cpd]) among children residing in buildings with colocated dry cleaners when indoor air perc level averaged 336 ?g/m³; breath perc level averaged 159.5 ?g/m³; and blood perc level averaged 0.51 ?g/L. Adjusted logistic regression indicated that increases in indoor air, breath, and blood perc levels among all child participants significantly increased the odds for decreased VCS at 12 cpd. Adult VCS was not significantly decreased by increasing indoor air, breath, or blood perc level. These results suggest that elevated residential perc exposures may alter children's VCS, a possible subclinical central nervous system effect. PMID:21864105

  8. Dose-excretion relationship in tetrachloroethylene-exposed workers and the effect of tetrachloroethylene co-exposure on trichloroethylene metabolism

    SciTech Connect

    Seiji, K.; Inoue, O.; Jin, C.; Liu, Y.T.; Cai, S.X.; Ohashi, M.; Watanabe, T.; Nakatsuka, H.; Kawai, T.; Ikeda, M. (Tohoku Univ. School of Medicine, Sendai (Japan))

    1989-01-01

    Personal monitoring of 8-hour time-weighted average intensity of exposure with diffuse samplers and analysis of shift-end urine for total trichloro-compounds (TTC) and other metabolites were conducted in two groups of workers in China, one (121 subjects) exposed to tetrachloroethylene (TETRA) alone, and the other (38 subjects) exposed to a mixture of TETRA and trichloroethylene (TRI). Urinalysis was also performed on samples from 103 non-exposed controls. A linear exposure-excretion relationship could be observed in both groups of workers. Comparison of these results with those of Japanese TETRA-workers suggested the presence of ethnic difference in TETRA metabolism. Urinary metabolite levels were markedly lower in the mixed (TETRA + TRI) exposure group as compared to previous findings in a group exposed to TRI alone. The observation indicates that metabolism of TRI is suppressed by the co-exposure to TETRA in humans.

  9. RESPONSE TO ISSUES AND DATA SUBMISSIONS ON THE CARCINOGENICITY OF TETRACHLOROETHYLENE (PERCHLOROETHYLENE)

    EPA Science Inventory

    The scientific debate over the potential carcinogenicity of tetrachloroethylene (perchloroethylene, perc, PCE) spans several years. his document reviews the issues considered by the EPA's Science Advisory Board (SAB) during its review of the Draft Addendum to the Health Assessmen...

  10. SUMMARY REPORT OF THE PEER REVIEW WORKSHOP ON THE NEUROTOXICITY OF TETRACHLOROETHYLENE (PERCHLOROETHYLENE) DISCUSSION PAPER

    EPA Science Inventory

    The report, Summary Report of the Peer Review Workshop on the Neurotoxicity of Tetrachloroethylene (Perchloroethylene) Discussion , summarizes the discussions at a February 25, 2004, workshop that brought together recognized scientific experts to engage in a public discussi...

  11. SURFACTANT-ENHANCED SOLUBILIZATION OF TETRACHLOROETHYLENE AND DEGRADATION PRODUCTS IN PUMP AND TREAT REMEDIATION

    EPA Science Inventory

    Experiments were conducted to investigate the enhanced solubilization of tetrachloroethylene (PCE), trichloroethylene (TCE), and 1,2-dichloroethylene (DCE) in nonionic surfactant solutions of Triton X-100, Brij-30, Igepal CA-720, and Tergitol NP-10 (alkylpolyoxyethylenes). urfact...

  12. THE ADDITION OF CYCLIC ETHERS TO TETRACHLOROETHYLENE BY THE $gamma$RAY IRRADIATION

    Microsoft Academic Search

    T. Matsuda; T. Yumoto; K. Iseda

    1963-01-01

    The radiation-induced addition reaction between tetrachloroethylene and ; cyclic ethers, tetrahydrofuran and paradioxane, was studied. In a glass ampule ; tetrachloroethylene and cyclic ether were placed and the ampule was deaerated, ; sealed, and then irradiated with gamma rays at a dose rate of 1.2 to 6.0 x 10\\/sup ; 4\\/ r\\/hr at room temperature. The reaction mixture was distilled

  13. Prenatal and Early Childhood Exposure to Tetrachloroethylene and Adult Vision

    PubMed Central

    Getz, Kelly D.; Janulewicz, Patricia A.; Rowe, Susannah; Weinberg, Janice M.; Winter, Michael R.; Martin, Brett R.; Vieira, Veronica M.; White, Roberta F.

    2012-01-01

    Background: Tetrachloroethylene (PCE; or perchloroethylene) has been implicated in visual impairments among adults with occupational and environmental exposures as well as children born to women with occupational exposure during pregnancy. Objectives: Using a population-based retrospective cohort study, we examined the association between prenatal and early childhood exposure to PCE-contaminated drinking water on Cape Cod, Massachusetts, and deficits in adult color vision and contrast sensitivity. Methods: We estimated the amount of PCE that was delivered to the family residence from participants’ gestation through 5 years of age. We administered to this now adult study population vision tests to assess acuity, contrast sensitivity, and color discrimination. Results: Participants exposed to higher PCE levels exhibited lower contrast sensitivity at intermediate and high spatial frequencies compared with unexposed participants, although the differences were generally not statistically significant. Exposed participants also exhibited poorer color discrimination than unexposed participants. The difference in mean color confusion indices (CCI) was statistically significant for the Farnsworth test but not Lanthony’s D-15d test [Farnsworth CCI mean difference = 0.05, 95% confidence interval (CI): 0.003, 0.10; Lanthony CCI mean difference = 0.07, 95% CI: –0.02, 0.15]. Conclusions: Prenatal and early childhood exposure to PCE-contaminated drinking water may be associated with long-term subclinical visual dysfunction in adulthood, particularly with respect to color discrimination. Further investigation of this association in similarly exposed populations is necessary. PMID:22784657

  14. Tetrachloroethylene Exposure and Bladder Cancer Risk: A Meta-Analysis of Dry-Cleaning-Worker Studies

    PubMed Central

    Vlaanderen, Jelle; Straif, Kurt; Ruder, Avima; Blair, Aaron; Hansen, Johnni; Lynge, Elsebeth; Charbotel, Barbara; Loomis, Dana; Kauppinen, Timo; Kyyronen, Pentti; Pukkala, Eero; Weiderpass, Elisabete

    2014-01-01

    Background: In 2012, the International Agency for Research on Cancer classified tetrachloroethylene, used in the production of chemicals and the primary solvent used in dry cleaning, as “probably carcinogenic to humans” based on limited evidence of an increased risk of bladder cancer in dry cleaners. Objectives: We assessed the epidemiological evidence for the association between tetrachloroethylene exposure and bladder cancer from published studies estimating occupational exposure to tetrachloroethylene or in workers in the dry-cleaning industry. Methods: Random-effects meta-analyses were carried out separately for occupational exposure to tetrachloroethylene and employment as a dry cleaner. We qualitatively summarized exposure–response data because of the limited number of studies available. Results: The meta-relative risk (mRR) among tetrachloroethylene-exposed workers was 1.08 (95% CI: 0.82, 1.42; three studies; 463 exposed cases). For employment as a dry cleaner, the overall mRR was 1.47 (95% CI: 1.16, 1.85; seven studies; 139 exposed cases), and for smoking-adjusted studies, the mRR was 1.50 (95% CI: 0.80, 2.84; 4 case–control studies). Conclusions: Our meta-analysis demonstrates an increased risk of bladder cancer in dry cleaners, reported in both cohort and case–control studies, and some evidence for an exposure–response relationship. Although dry cleaners incur mixed exposures, tetrachloroethylene could be responsible for the excess risk of bladder cancer because it is the primary solvent used and it is the only chemical commonly used by dry cleaners that is currently identified as a potential bladder carcinogen. Relatively crude approaches in exposure assessment in the studies of “tetrachloroethylene-exposed workers” may have attenuated the relative risks. Citation: Vlaanderen J, Straif K, Ruder A, Blair A, Hansen J, Lynge E, Charbotel B, Loomis D, Kauppinen T, Kyyronen P, Pukkala E, Weiderpass E, Guha N. 2014. Tetrachloroethylene exposure and bladder cancer risk: a meta-analysis of dry-cleaning-worker studies. Environ Health Perspect 122:661–666;?http://dx.doi.org/10.1289/ehp.1307055 PMID:24659585

  15. SUBCHRONIC TOXICITY OF TETRACHLOROETHYLENE (PERCHLOROETHYLENE) ADMINISTERED IN THE DRINKING WATER OF RATS

    EPA Science Inventory

    The study provides data on the effects of tetrachloroethylene in drinking solutions. The acute oral LD(50) was determined in male and female Charles River rats and found to be 3835 mg/kg for males and 3005 mg/kg for females. Male and female rats received theoretical daily doses o...

  16. EVALUATION OF GEOPHYSICAL METHODS FOR THE DETECTION OF SUBSURFACE TETRACHLOROETHYLENE (PCE) IN CONTROLLED SPILL EXPERIMENTS

    EPA Science Inventory

    Tetrachloroethylene (PCE), typically used as a dry cleaning solvent, is a predominant contaminant in the subsurface at Superfund Sites. PCE is a dense non-aqueous phase liquid (DNAPL) that migrates downward into the earth, leaving behind areas of residual saturation and free prod...

  17. A first French assessment of population exposure to tetrachloroethylene from small dry cleaning facilities

    E-print Network

    Paris-Sud XI, Université de

    -integrated concentrations on a 7 days sampling period. It has obviously shown the degradation of indoor air quality: tetrachloroethylene, dry cleaning facilities, indoor air quality, passive sampling, population exposure. Practical of residential indoor air, which can cause long term harmful exposures because of its neurotoxicity and probable

  18. Continuous Determination of High-Vapor Phase Concentrations of Tetrachloroethylene Using On-Line Mass Spectrometry

    EPA Science Inventory

    A method was developed to determine the vapor concentration of tetrachloroethylene (PCE) at and below its equilibrium vapor phase concentration, 168,000 µg/L (25°C). Vapor samples were drawn by vacuum into a six-port sampling valve and injected through a jet separator into an io...

  19. Subchronic toxicity of tetrachloroethylene (perchloroethylene) administered in the drinking water of rats

    SciTech Connect

    Hayes, J.R.; Condie, L.W. Jr.; Borzelleca, J.F.

    1986-07-01

    This study provides data on the effects of tetrachloroethylene in drinking solutions. The acute oral LD50 in male and female Charles River rats was found to be 3835 mg/kg for males and 3005 mg/kg for females. Male and female rats received theoretical daily doses of 14,400, and 1400 mg tetrachloroethylene/kg body wt/day for 90 consecutive days. There were no compound-related deaths. Body weights were significantly lower in male and female rats at the higher doses. There were no consistent dose-related effects on any of the hematological, clinical chemistry, or urinalysis parameters. 5'-Nucleotidase activity was increased in a dose-dependent manner, suggesting possible hepatotoxicity; however, other serum indicators of hepatic function were unaffected by the treatment. There were no gross pathological effects observed. Liver and kidney body weight ratios, but not brain weight ratios, were elevated at the higher doses. There was no other evidence of compound-related toxicity. These data suggest that exposure of humans to reported levels of tetrachloroethylene in drinking water (approximately 1 microgram/liter) does not constitute a serious health hazard.

  20. Use of Mini-Sprinklers to Strip Trichloroethylene and Tetrachloroethylene from Contaminated Ground Water.

    SciTech Connect

    Brerisford, Yvette, C.; Bush, Parshall, B.; Blake, John, I.; Bayer, Cassandra L.

    2003-01-01

    Berisford, Y.C., P.B. Bush, J.I. Blake, and C.L. Bayer. 2003. Use of mini-sprinklers to strip trichloroethylene and tetrachloroethylene from contaminated ground water. J. Env. Qual. 32:801-815. Three low-volume mini-sprinklers were tested for their efficacy to strip trichloroethylene (TCE) and tetrachloroethylene (PCE) from water. Deionized water spiked with TCE and PCE was pumped through a mini-sprinkler supported on top of a 1.8-m-tall. Water was collected in collection vessels at 0.61 and 1.22 m above the ground on support columns that were spaced at 0.61-m intervals from the riser base, and samples were composited per height and distance from the riser. Overall, air-stripping reduced dissolved concentrations of TCE and PCE by 99.1 to 100 and 96.9 to 100%, respectively. Mini-sprinklers offer the advantages of (i) easy setup in series that can be used on practically any terrain; (ii) operation over a long period of time that does not threaten aquifer depletion; (iii) use in small or confined aquifers in which the capacity is too low to support large irrigation or pumping systems; and (iv) use in forests in which the small, low-impact droplets of the mini-sprinklers do not damage bark and in which trees can help manage (via evapotransporation) excess waste water.

  1. SURFACTANT ENHANCED RECOVERY OF TETRACHLOROETHYLENE FROM A POROUS MEDIUM CONTAINING LOW PERMEABILITY LENSES. 1. EXPERIMENTAL STUDIES. (R825409)

    EPA Science Inventory

    Abstract A matrix of batch, column and two-dimensional (2-D) box experiments was conducted to investigate the coupled effects of rate-limited solubilization and layering on the entrapment and subsequent recovery of a representative dense NAPL, tetrachloroethylene (PCE)...

  2. ADVANCED OXIDATION PROCESSES FOR TREATING GROUNDWATER CONTAMINATED WITH TCE (TRICHLOROETHYLENE) AND PCE (TETRACHLOROETHYLENE): LABORATORY STUDIES (JOURNAL VERSION)

    EPA Science Inventory

    Oxidation of trichloroethylene (TCE) and tetrachloroethylene (PCE) with various dosages of ozone or ozone plus hydrogen peroxide was studied in laboratory experiments. The results show that hydrogen peroxide accelerates the oxidation of TCE and PCE by ozone. At peroxide-to-ozone ...

  3. Simulation calculations of tetrachloroethylene decomposition in air mixtures under electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Sun, Y.; Chmielewski, A. G.; Bu?ka, S.; Zimek, Z.; Nichipor, H.

    2009-07-01

    Theoretical simulation calculations of tetrachloroethylene (PCE) decomposition in air mixtures under electron beam (EB) irradiation have been carried out based on the experimental results. A computer code Kinetic and a Gear method were used and 324 reactions and 76 species were considered. From calculated results, we learn that more than 99% PCE is decomposed at 4.4 kGy dose when the initial concentration of PCE is 322 ppm; concentrations of inorganic carbons (CO+CO 2) increases with the dose, and the relative carbon concentration of inorganic carbons is about 17% at 13.1 kGy; phosgene (COCl 2) and trichloroacetyl chloride (CCl 3COCl) are predicted as main organic products and are confirmed by the experimental results. The good agreement is obtained between the calculated results and the experimental data.

  4. Excretion of organic chlorine compounds in the urine of persons exposed to vapours of trichloroethylene and tetrachloroethylene

    PubMed Central

    Ogata, Masana; Takatsuka, Yoshiko; Tomokuni, Katsumaro

    1971-01-01

    Ogata, M., Yoshiko, T., and Tomokuni, K. (1971).Brit. J. industr. Med.,28, 386-391. Excretion of organic chlorine compounds in the urine of persons exposed to vapours of trichloroethylene and tetrachloroethylene. Male volunteers were exposed to 170 p.p.m. of trichloroethylene vapour either for 3 hours or for 7 hours with one break of 1 hour; or to 87 p.p.m. of tetrachloroethylene vapour for 3 hours. Urine was collected frequently up to 100 hours after the start of exposure, and was analysed for trichloroethanol and trichloroacetic acid. After trichloroethylene exposure, trichloroethanol was excreted most rapidly shortly after exposure ceased, and trichloroacetic acid most rapidly 42 to 69 hours after exposure ceased. Total recoveries of trichloroethylene inhaled, up to 100 hours, were: trichloroethanol, after 3 hours' exposure, 53·1%; after 7 hours' exposure, 44%; trichloroacetic acid, similarly: 21·9% and 18·1%. The effects of exposure on blood pressure, pulse rate, flicker value, and reaction time were measured. The diastolic blood pressure was decreased significantly after 3 hours' exposure to 170 p.p.m. trichloroethylene. After tetrachloroethylene exposure, in 67 hours trichloroacetic acid was excreted to 1·8% tetrachloroethylene retained and an unknown chloride equivalent to 1·0%. Urine samples from 10 workers in an automobile parts factory were analysed for trichloroethanol and trichloroacetic acid. Trichloroethanol concentrations in the urine taken after work were higher than in the urine taken before work while for trichloroacetic acid the concentrations were reversed, due to the difference in the time course of excretion. The urinary levels of trichloroethanol, trichloroacetic acid, and total trichloro compounds were almost proportional to the environmental concentration of trichloroethylene. PMID:5124840

  5. Integrating Address Geocoding, Land Use Regression, and Spatiotemporal Geostatistical Estimation for Groundwater Tetrachloroethylene

    PubMed Central

    Messier, Kyle P.; Akita, Yasuyuki; Serre, Marc L.

    2012-01-01

    Geographic Information Systems (GIS) based techniques are cost-effective and efficient methods used by state agencies and epidemiology researchers for estimating concentration and exposure. However, budget limitations have made statewide assessments of contamination difficult, especially in groundwater media. Many studies have implemented address geocoding, land use regression, and geostatistics independently, but this is the first to examine the benefits of integrating these GIS techniques to address the need of statewide exposure assessments. A novel framework for concentration exposure is introduced that integrates address geocoding, land use regression (LUR), below detect data modeling, and Bayesian Maximum Entropy (BME). A LUR model was developed for Tetrachloroethylene that accounts for point sources and flow direction. We then integrate the LUR model into the BME method as a mean trend while also modeling below detects data as a truncated Gaussian probability distribution function. We increase available PCE data 4.7 times from previously available databases through multistage geocoding. The LUR model shows significant influence of dry cleaners at short ranges. The integration of the LUR model as mean trend in BME results in a 7.5% decrease in cross validation mean square error compared to BME with a constant mean trend. PMID:22264162

  6. A risk-based cleanup criterion for PCE in soil. [Tetrachloroethylene

    SciTech Connect

    Daniels, J.I.; McKone, T.E.; Hall, L.C.

    1990-09-26

    The most important attribute of a chemical contaminant at a hazardous-wastes site for decision makers to consider with regard to its cleanup is the potential risk associated with human exposure. For this reason we have developed a strategy for establishing a risk-based cleanup criterion for chemicals in soil. We describe this strategy by presenting a cleanup criterion for tetrachloroethylene (PCE) in soil associated with a representative California landscape. We being by discussing the environmental fate and transport model, developed at the Lawrence Livermore National Laboratory (LLNL), that we used to predict the equilibrium concentration of PCE in five environmental media from a steady-state source in soil. Next, we explain the concept and application of pathway-exposure factors (PEFs), the hazard index, and cancer-potency factors (CPFs) for translating the predicted concentrations of PCE into estimated potential hazard or risk for hypothetically exposed individuals. Finally, the relationship between concentration and an allowable level of risk is defined and the societal and financial implications are discussed. 22 refs., 6 tabs.

  7. Continuous determination of high-vapor-phase concentrations of tetrachloroethylene using on-line mass spectrometry.

    PubMed

    Fine, Dennis; Brooks, Michael C; Bob, Mustafa; Mravik, Susan; Wood, Lynn

    2008-02-15

    A method was developed to determine the vapor concentration of tetrachloroethylene (PCE) at and below its equilibrium vapor-phase concentration, 168 000 microg/L (25 degrees C). Vapor samples were drawn by vacuum into a six-port sampling valve and injected through a jet separator into an ion trap mass spectrometer (MS). This on-line MS can continuously sample a vapor stream and provide vapor concentrations every 30 s. Calibration of the instrument was done by creating a saturated stream of PCE vapor, sampling the vapor with the on-line MS and with thermal desorption tubes, and correlating the peak area response from the MS with the vapor concentration determined by automated thermal desorption gas chromatography mass spectrometry. Dilution of the saturated stream provided lower concentrations of PCE vapor. The method was developed to monitor the vapor concentration of PCE that was sparged from a two-dimensional flow chamber and for determination of the total PCE mass removed during each sparge event. The method has potential application for analysis of gas-phase tracers. PMID:18205332

  8. Biological degradation of tetrachloroethylene in methanogenic conditions. Final report, 12 July 1991-11 January 1993

    SciTech Connect

    Gossett, J.M.; DiStefano, T.D.; Stover, M.A.

    1994-06-01

    Research objective: investigate anaerobic biodegradation of perchloroethylene (PCE). Specific objectives: determine if the presence of PCE is necessary to sustain dechlorination of vinyl chloride (VC), delineate the role of hydrogen (H2) in PCE reductive dechlorination, investigate the ability of the high level PCE/methanol (MeOH) culture to utilize low levels of PCE, and determine the applicability of an Anaerobic Attached-film Expanded-bed (AAFEB) reactor to achieve PCE dechlorination. The investigators determined: by using a VC-fed culture unable to sustain ETH production, that the presence of PCE is required to sustain VC dechlorination, H2 acts as the electron donor directly used for the reductive dechlorination of PCE to ethene, the PCE/MeOH culture was able to use ppb levels of PCE due to the small requirement for electron donor (H2) by the culture, and that the loss of the dechlorinating biomass from the support matrix, and/or the inability of the culture to support PCE dechlorination at low concentrations, led to the failure of the AAFEB reactor system. Biodegradation, Tetrachloroethylene, Methanogenesis, Fixed-film reactors, Biological treatment, Chlorinated hydrocarbons.

  9. Adult Neuropsychological Performance Following Prenatal and Early Postnatal Exposure to Tetrachloroethylene (PCE)-contaminated Drinking Water

    PubMed Central

    Janulewicz, Patricia A; White, Roberta F; Martin, Brett M; Winter, Michael R; Weinberg, Janice M; Vieira, Veronica; Aschengrau, Ann

    2012-01-01

    This population-based retrospective cohort study examined adult performance on a battery of neuropsychological tests in relation to prenatal and early postnatal exposure to tetrachloroethylene (PCE)-contaminated drinking water on Cape Cod, Massachusetts. Subjects were identified through birth records from 1969 through 1983. Exposure was modeled using pipe network information from town water departments, a PCE leaching and transport algorithm, EPANet water flow modeling software, and a Geographic Information System (GIS). Results of crude and multivariate analyses among 35 exposed and 28 unexposed subjects showed no association between prenatal and early postnatal exposure and decrements on tests that assess abilities in the domains of omnibus intelligence, academic achievement or language. The results were suggestive of an association between prenatal and early postnatal PCE exposure and diminished performance on tests that assessed abilities in the domains of visuospatial functioning, learning and memory, motor, attention and mood. Because the sample size was small, most findings were not statistically significant. Future studies with larger sample sizes should be conducted to further define the neuropsychological consequences of early developmental PCE exposure. PMID:22522125

  10. Interfacial Properties of a Hydrophobic Dye in the Tetrachloroethylene-Water-Glass Systems

    SciTech Connect

    Tuck, D.M.

    1999-02-23

    Interfacial effects play an important role in governing multiphase fluid behavior in porous media. Strongly hydrophobic organic dyes, used in many experimental studies to facilitate visual observation of the phase distributions, have generally been implicitly assumed to have no influence on the interfacial properties of the various phases in porous media. Sudan IV is the most commonly used dye for non-aqueous phase liquids (NAPLs) in laboratory experiments. It has also been used in at least one field experiment. The effects of this dye on the tetrachloroethylene (PCE)-water-glass system were investigated to test the assumption that the dye does not effect the interfacial properties and therefore PCE mobility. The results indicate that the dye does indeed change the interfacial relationships.The effect of the dye on the interfacial relationships is a complex function of the dye concentration, the solid phase composition, and the dynamic rate of new interface formation. The dye caused a slight (<10 percent) increase in interfacial tension at low concentrations (<0.1 g/L) and high rates of new interface formation. The dye reduced interfacial tension between PCE and water at low rates of new interface formation for all dye concentrations tested (0.00508 to 5.08 g/L). At the highest dye concentration, the PCE-water interfacial tension was significantly reduced regardless of the rate of new interface formation. The apparent interfacial tension increase at low dye concentrations is suspected to be an artifact of a low measured IFT value for the undyed PCE caused by leaching of rubber o-rings by the PCE prior to testing in the final drop-volume configuration.In addition to reducing interfacial tension, the dye was found to significantly alter the wetting relationship between PCE and water on a glass surface at and above the range of reported dye concentrations cited in the literature (1.1 to 1.7 g/L). The wetting relationship was rendered neutral from a water-wet initial condition at the highest dye concentration. The contact angle, measured through the aqueous phase, changed from 58 degrees for undyed PCE to 93 degrees at a dye concentration of 5.08 g/L. Complete reversal of the wettability is likely given the short equilibration time used in this study (approximately five minutes) together with literature indications that hundreds to thousands of hours may be required to reach equilibrium during contact angle measurements. Observations suggesting changing wetting relationships were also noted between PCE, water, and the platinum-iridium surface used in the standard du No/374y ring method for measuring interfacial tension.Observations of the dyed-PCE-water interface behavior during du No/374y ring interfacial tension measurements were similar to observations noted previously during measurements of the interfacial tension between the Savannah River Site (SRS) M-Area Settling Basin DNAPL (M-Area DNAPL) and water. This observation suggests that the M-Area DNAPL may contain surface active components. If this proves to be the case, it would have significant implications for how the M-Area DNAPL is distributed and moves in the SRS subsurface.

  11. Surfactant-enhanced solubilization of tetrachloroethylene and degradation products in pump-and-treat remediation. Book chapter

    SciTech Connect

    West, C.C.

    1992-01-01

    Experiments were conducted to investigate the enhanced solubilization of tetrachloroethylene (PCE), trichloroethylene (TCE), and 1,2-dichloroethylene (DCE) in nonionic surfactant solutions of Triton X-100, Brij-30, Igepal CA-720, and Tergitol NP-10 (alkylpolyoxyethylenes). Surfactant solubilization is being considered as a means to enhance mobile phase solubilities of ground-water contaminants for the purpose of improving the efficiency of pump and treat remediation. The primary objectives of the study were to observe the solubilization of relatively hydrophilic organic solutes at system temperatures similar to ground-water conditions and to determine if solubilization can be linearly correlated to the octanol/water partition coefficient, as has been observed by others for hydrophobic organic solutes. The results of the study show that surfactant solubilization of hydrophilic solutes is highly correlated with their octanol/water partition coefficient when corrected for temperature effects. It was also observed that there appears to be little difference in solubilizing efficiency between the four surfactants.

  12. Non-steady state partitioning of dry cleaning surfactants between tetrachloroethylene (PCE) and water in porous media

    NASA Astrophysics Data System (ADS)

    Hoggan, James L.; Bae, Keonbeom; Kibbey, Tohren C. G.

    2007-08-01

    Trapped organic solvents, in both the vadose zone and below the water table, are frequent sources of environmental contamination. A common source of organic solvent contamination is spills, leaks, and improper solvent disposal associated with dry cleaning processes. Dry cleaning solvents, such as tetrachloroethylene (PCE), are typically enhanced with the addition of surfactants to improve cleaning performance. The objective of this work was to examine the partitioning behavior of surfactants from PCE in contact with water. The relative rates of surfactants partitioning and PCE dissolution are important for modeling the behavior of waste PCE in the subsurface, in that they influence the interfacial tension of the PCE, and how (or if) interfacial tension changes over time in the subsurface. The work described here uses a flow-through system to examine simultaneous partitioning and PCE dissolution in a porous medium. Results indicate that both nonylphenol ethoxylate nonionic surfactants and a sulfosuccinate anionic surfactant partition out of residual PCE much more rapidly than the PCE dissolves, suggesting that in many cases interfacial tension changes caused by partitioning may influence infiltration and distribution of PCE in the subsurface. Non-steady-state partitioning is found to be well-described by a linear driving force model incorporating measured surfactant partition coefficients.

  13. The effect of low concentrations of tetrachloroethylene on H2 adsorption and activation on Pt in a fuel cell catalyst

    NASA Astrophysics Data System (ADS)

    Zhang, Jack Z.; Colón-Mercado, Héctor R.; Goodwin, James G.

    2011-10-01

    The poisoning effect of tetrachloroethylene (TTCE) on the activity of a Pt fuel cell catalyst for the adsorption and activation of H2 was investigated at 60 °C and 2 atm using hydrogen surface concentration measurements. The impurity was chosen as a model compound for chlorinated cleaning and degreasing agents that may be introduced into a fuel cell as a contaminant at a fueling station and/or during vehicle maintenance. In the presence of only H2, introduction of up to 540 ppm TTCE in H2 to Pt/C resulted in a reduction of available Pt surface atoms (measured by H2 uptake) by ca. 30%, which was not enough to shift the H2-D2 exchange reaction away from being equilibrium limited. Exposure of TTCE to Pt/C in a mixed redox environment (hydrogen + oxygen), similar to that at the cathode of a fuel cell, resulted in a much more significant loss of Pt surface atom availability, suggesting a role in TTCE decomposition and/or Cl poisoning. Regeneration of catalyst activity of poisoned Pt/C showed the highest level of recovery when regenerated in only H2, with much less recovery in H2 + O2 or O2. The results from this study are in good agreement with those found in a fuel cell study by Martínez-Rodríguez et al. [2] and confirm that the majority of the poisoning from TTCE on fuel cell performance is most likely at the cathode, rather than the anode.

  14. Prenatal exposure to tetrachloroethylene-contaminated drinking water and the risk of congenital anomalies: a retrospective cohort study

    PubMed Central

    2009-01-01

    Background Prior animal and human studies of prenatal exposure to solvents including tetrachloroethylene (PCE) have shown increases in the risk of certain congenital anomalies among exposed offspring. Objectives This retrospective cohort study examined whether PCE contamination of public drinking water supplies in Massachusetts influenced the occurrence of congenital anomalies among children whose mothers were exposed around the time of conception. Methods The study included 1,658 children whose mothers were exposed to PCE-contaminated drinking water and a comparable group of 2,999 children of unexposed mothers. Mothers completed a self-administered questionnaire to gather information on all of their prior births, including the presence of anomalies, residential histories and confounding variables. PCE exposure was estimated using EPANET water distribution system modeling software that incorporated a fate and transport model. Results Children whose mothers had high exposure levels around the time of conception had an increased risk of congenital anomalies. The adjusted odds ratio of all anomalies combined among children with prenatal exposure in the uppermost quartile was 1.5 (95% CI: 0.9, 2.5). No meaningful increases in the risk were seen for lower exposure levels. Increases were also observed in the risk of neural tube defects (OR: 3.5, 95% CI: 0.8, 14.0) and oral clefts (OR 3.2, 95% CI: 0.7, 15.0) among offspring with any prenatal exposure. Conclusion The results of this study suggest that the risk of certain congenital anomalies is increased among the offspring of women who were exposed to PCE-contaminated drinking water around the time of conception. Because these results are limited by the small number of children with congenital anomalies that were based on maternal reports, a follow-up investigation should be conducted with a larger number of affected children who are identified by independent records. PMID:19778411

  15. Structural Magnetic Resonance Imaging in an Adult Cohort Following Prenatal and Early Postnatal Exposure to Tetrachloroethylene (PCE)-contaminated Drinking Water

    PubMed Central

    Janulewicz, Patricia A; Killiany, Ronald J; White, Roberta F; Martin, Brett M; Winter, Michael R; Weinberg, Janice M; Aschengrau, Ann

    2013-01-01

    This population-based retrospective cohort study examined Structural Magnetic Resonance Imaging (MRI) of the brain in relation to prenatal and early postnatal exposure to tetrachloroethylene (PCE)-contaminated drinking water on Cape Cod, Massachusetts. Subjects were identified through birth records from 1969 through 1983. Exposure was modeled using pipe network information from town water departments, a PCE leaching and transport algorithm, EPANet water flow modeling software, and Geographic Information System (GIS) methodology. Brain imaging was performed on 26 exposed and 16 unexposed subjects. Scans were acquired on a Philips 3T whole body scanner using the ADNI T1-weighted MP-RAGE scan. The scans were processed by FreeSurfer version 4.3.1 software to obtain measurements of specific brain regions. There were no statistically significant differences between exposed and unexposed subjects on measures of white matter hypointensities (?: 127.5 mm3, 95% CI: ?259.1, 1514.0), white matter volumes (e.g. total cerebral white matter: ?: 21230.0 mm3, 95% CI: ?4512.6, 46971.7) or gray matter volumes (e.g. total cerebral gray matter: ?: 11976.0 mm3, 95% CI: ?13657.2, 37609.3). The results of this study suggest that exposure to PCE during gestation and early childhood, at the levels observed in this population, is not associated with alterations in the brain structures studied. PMID:23571160

  16. NEUROTOXICITY OF TETRACHLOROETHYLENE (PERCHLOROETHYLENE): DISCUSSION PAPER

    EPA Science Inventory

    This paper is a background document for a meeting of neurotoxicity experts to discuss the central nervous system effects of exposure to perchloroethylene (perc). The document reviews the literature on neurological testing of people exposed to perc occupationally in dry cleanin...

  17. Tetrachloroethylene Degradation by Dithionite with Ultraviolet Activation 

    E-print Network

    Zhang, Jingyuan

    2013-07-30

    experiments (blank control, reagent control and UV control) were conducted to prove the feasibility of applying the dithionite/UV ARP to degrade PCE. ARP degradation of PCE was studied under different pH (5, 7, 8, 9) and light intensities (2, 4, 7.3 mW/cm2...

  18. Tetrachloroethylene Degradation by Dithionite with Ultraviolet Activation

    E-print Network

    Zhang, Jingyuan

    2013-07-30

    . Effect of light intensity on pseudo-first-order rate constants. .......................... 29 viii LIST OF TABLES Page Table 1: Initial rate and pseudo-first-order rate constant for reagent control experiment.... ............................................................................ 28 Table 7: Nomenclature.. ................................................................................................... 30 Table 8: Regression analysis of light intensities and rate constants????????.32 Table A-1: The loss of PCE during...

  19. Arc products of transformer insulating systems containing tetrachloroethylene. Final report

    SciTech Connect

    Baum, B.; Boshart-Mikes, G.; Mikes, F.; Mulak, M.; Peck, W.R.; Mandelcorn, L.; Jones, E.A.; Marshall, G.R.; Studniartz, S.A.

    1986-03-01

    A low current laboratory arc interruption cell was adapted to study the arc products of Wecosol (C/sub 2/Cl/sub 4/) and 75W% C/sub 2/Cl/sub 4/-25W% mineral oil-solid insulation systems for fire resistant transformers to determine the toxicity hazard of arc failures of these transformers. The use of the relatively low current (40 to 50 ampere) arcs was justified on the basis that their maximum temperature was above the chemical reaction temperatures just as in the case of kiloampere arc failures of transformers. Analytical methods were developed to determine arc products, principally for COCl/sub 2/ (phosgene). A relative hazard criterion is presented. The major arc products of the Wecosol systems are Cl/sub 2/, HCl, C/sub 2/Cl/sub 6/ (reaction of Cl/sub 2/ + C/sub 2/Cl/sub 4/) and CCl/sub 4/, and the minor products are COCl/sub 2/, CO and CO/sub 2/. The principal arc failure hazard here would be due to Cl/sub 2/ and HCl, and there is a low probability of COCl/sub 2/ and CO hazards. The major arc products in the 75W% C/sub 2/Cl/sub 4/ + 25W% mineral oil systems are HCl and CCl/sub 4/, and HCl would present the principal arc failure hazard. The minor products include COCl/sub 2/ and H/sub 2/, and COCl/sub 2/ would present a low probability of toxicity hazard. The levels of H/sub 2/ were well below the explosive limits of H/sub 2/ and air. It was concluded that failure arc products from these C/sub 2/Cl/sub 4/ fluid based transformers should not be hazardous in most instances of failure, and that simple precautions would be sufficient to assure safe access and handling. 6 figs., 11 tabs.

  20. Mobilization of residual tetrachloroethylene during alcohol flushing of clay-containing porous media

    NASA Astrophysics Data System (ADS)

    Padgett, Parminder K.; Hayden, Nancy J.

    1999-12-01

    Mobilization of residual DNAPL in a contaminated aquifer may be problematic for the application of enhanced dissolution remediation techniques such as alcohol or surfactant flushing. The objective of this study was to investigate the effects of clay fines on residual saturation, permeability and the onset of mobilization of PCE during alcohol flushing. Column experiments were conducted with soils containing 0%, 2%, 5%, 10%, and 20% clay that was completely mixed within a well-sorted Ottawa sand. Column characterization included pressure-saturation relationships, pore-size distribution, permeability, and residual saturation. The columns were flushed with isopropyl alcohol (IPA) in concentration increments to determine when mobilization of PCE occurred. Trapping numbers were calculated. Results showed that increasing amounts of clay resulted in decreased hydraulic conductivity, increased residual PCE saturation and a larger pore size distribution. Residual PCE was found to begin to mobilize in the clay-mixed media at a range of trapping numbers below those reported in the literature for homogeneous well-sorted sand. This suggests that the potential to mobilize the residual PCE is greater in the mixed media. This may be explained by the formation of multi-pore branched ganglia in the clay-containing media as opposed to singlet formation in a well-sorted media. The multi-pore ganglia may mobilize more readily than singlets due to the added force of head acting on the PCE interface where the trapping is occurring. Using a narrow range of trapping numbers determined in homogeneous media to predict mobilization may not be appropriate in mixed media because mobilization was noted at a variety of trapping numbers. However, relationships between the trapping number at mobilization and various soil parameters such as the amount of clay, residual DNAPL saturation, and pore size distribution, indicate that these, coupled with the trapping number, may aid in our ability to predict mobilization.

  1. Identification of active agents for tetrachloroethylene degradation in Portland cement slurry containing ferrous iron

    E-print Network

    Ko, Sae Bom

    2006-08-16

    Fe(II)-based degradative solidification/stabilization (Fe(II)-DS/S) technology is the modification of conventional solidification/stabilization (S/S). Inorganic pollutants are immobilized by Fe(II)-DS/S while organic pollutants are destroyed...

  2. Identification of active agents for tetrachloroethylene degradation in Portland cement slurry containing ferrous iron 

    E-print Network

    Ko, Sae Bom

    2006-08-16

    -EDS) were used to identify minerals in chemical mixtures that have high activities. Results indicate that active agents for PCE degradation in Portland cement slurries and in cement extracts might be one of several AFm phases. However, systems without cement...

  3. 40 CFR 721.3560 - Derivative of tetra-chloro-ethy-lene.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...approved by the National Institute for Occupational Safety (NIOSH) to provide protection...according to procedures established by the Occupational Safety and Health Administration and...substances, chemical and mechanical stresses, and potential durations of...

  4. 40 CFR 721.3560 - Derivative of tetra-chloro-ethy-lene.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...approved by the National Institute for Occupational Safety (NIOSH) to provide protection...according to procedures established by the Occupational Safety and Health Administration and...substances, chemical and mechanical stresses, and potential durations of...

  5. 40 CFR 721.3560 - Derivative of tetra-chloro-ethy-lene.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...approved by the National Institute for Occupational Safety (NIOSH) to provide protection...according to procedures established by the Occupational Safety and Health Administration and...substances, chemical and mechanical stresses, and potential durations of...

  6. 40 CFR 721.3560 - Derivative of tetra-chloro-ethy-lene.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...approved by the National Institute for Occupational Safety (NIOSH) to provide protection...according to procedures established by the Occupational Safety and Health Administration and...substances, chemical and mechanical stresses, and potential durations of...

  7. 40 CFR 721.3560 - Derivative of tetra-chloro-ethy-lene.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...approved by the National Institute for Occupational Safety (NIOSH) to provide protection...according to procedures established by the Occupational Safety and Health Administration and...substances, chemical and mechanical stresses, and potential durations of...

  8. SURFACTANT ENHANCED RECOVERY OF TETRACHLOROETHYLENE FROM A POROUS MEDIUM CONTAINING LOW PERMEABILITY LENSES. 2. NUMERICAL SIMULATION. (R825409)

    EPA Science Inventory

    Abstract A numerical model of surfactant enhanced solubilization was developed and applied to the simulation of nonaqueous phase liquid recovery in two-dimensional heterogeneous laboratory sand tank systems. Model parameters were derived from independent, small-scale, ...

  9. 40 CFR 148.10 - Waste specific prohibitions-solvent wastes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...acetate Ethyl benzene Ethyl ether Isobutanol Methanol Methylene chloride Methylene chloride (from the pharmaceutical industry) Methyl ethyl ketone Methyl isobutyl ketone Nitrobenzene Pyridine Tetrachloroethylene Toulene...

  10. 40 CFR Table 6 to Part 455 - PSES and PSNS for Priority Pollutants

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Chloromethane 295 110 Cyanide (Total) 640 220 Dibromochloromethane 794 196 Dichloromethane 170 36 Ethylbenzene 380 142 Lead (Total) 690 320 Naphthalene 47 19 Tetrachloroethylene 164 52 Tetrachloromethane...

  11. NATURAL GRADIENT EXPERIMENT ON SOLUTE TRANSPORT IN A SAND AQUIFER. 4. SORPTION OF ORGANIC SOLUTES AND ITS INFLUENCE ON MOBILITY

    EPA Science Inventory

    Laboratory investigations were conducted to determine whether the observed field retardation of bromoform, carbon tetrachloride, tetrachloroethylene, 1,2-dichlorobenzene, and hexachloroethane at the Borden field site could be explained by the linear, reversible, equilibrium sorpt...

  12. CATALYTIC HYDRODEHALOGENATION OF CHLORINATED ETHYLENES USING PALLADIUM AND HYDROGEN FOR THE TREATMENT OF CONTAMINATED WATER. (R825689C054,R825689C060)

    EPA Science Inventory

    Abstract A kinetic model is presented for the catalytic hydrodehalogenation of chlorinated ethylenes using Pd and H2 under water treatment conditions. All five chlorinated ethylenes, including tetrachloroethylene (PCE) and vinyl chloride, were completely rem...

  13. BIOVENTING OF CHLORINATED SOLVENTS FOR GROUND-WATER CLEANUP THROUGH BIOREMEDIATION

    EPA Science Inventory

    Chlorinated solvents such as tetrachloroethylene, trichloroethylene, carbon tetrachloride, chloroform, 1,2-dichloroethane, and dichloromethane (methylene chloride) can exist in contaminated subsurface material as (1) the neat oil, (2) a component of a mixed oily waste, (3) a solu...

  14. ANAEROBIC BIOTRANSFORMATIONS OF POLLUTANT CHEMICALS IN AQUIFERS (JOURNAL VERSION)

    EPA Science Inventory

    Anaerobic microbial communities sampled from either a methanogenic or sulfate-reducing aquifer site have been tested for their ability to degrade a variety of groundwater pollutants, including halogenated aromatic compounds, simple alkyl phenols and tetrachloroethylene. The haloa...

  15. BIOTRANSFORMATION OF TRICHLOROETHYLENE IN SOIL

    EPA Science Inventory

    The organic contaminants that are most commonly detected in groundwater are low-molecular-weight, chlorinated aliphatic hydrocarbons such as trichloroethylene (TCE), tetrachloroethylene (PCE), 1,1,1-trichloroethane, carbon tetrachloride, and chloroform. The authors exposed unsatu...

  16. EMISSIONS OF PERCHLOROETHYLENE FROM DRY CLEANED FABRICS

    EPA Science Inventory

    A study was conducted to evaluate the emissions of perchloroethylene (tetrachloroethylene) from dry cleaned fabrics to determine: (a) how the introduction of fresh dry cleaning into a home affects the indoor concentration of perchloroethylene, and (b) the effectiveness of ?airing...

  17. EVALUATION OF HAZARDOUS WASTE INCINERATION IN AN AGGREGATE KILN: FLORIDA SOLITE CORPORATION

    EPA Science Inventory

    Aggregate kiln incineration of chlorinated liquid organic waste was investigated in a one-week program at Florida Solite Company. POHCs (toluene, tetrachloroethylene, methyl ethyl ketone, and methyl isobutyl ketone) were monitored in waste and stack emissions. In addition, stack ...

  18. Applications of Monitored Natural Attenuation in the USA (Presentation)

    EPA Science Inventory

    Monitored Natural Attenuation (MNA) is widely applied in the USA to control the risk associated with ground water contamination from chlorinated solvents such a tetrachloroethylene (PCE) and trichloroethylene (TCE). MNA relies on the natural processes of degradation, sorption an...

  19. Applications of Monitored Natural Attenuation in the USA (Abstract)

    EPA Science Inventory

    Monitored Natural Attenuation (MNA) is widely applied in the USA to control the risk associated with ground water contamination from chlorinated solvents such a tetrachloroethylene (PCE) and trichloroethylene (TCE). MNA relies on the natural processes of degradation, sorption an...

  20. IN-PLACE REGENERATION OF SVE LOADED GAC USING FENTON'S REAGENTS

    EPA Science Inventory

    Ten out of the 25 most frequently detected groundwater contaminants at hazardous waste sites are chlorinated volatile organic compounds (VOCs) 1 . Trichloroethylene (TCE) and tetrachloroethylene (PCE) are among the top three 1 . Granular activated carbon (GAC) adsorption is w...

  1. IN-PLACE REGENERATION OF SVE LOADED GAC USING FENTON'S REAGENTS

    EPA Science Inventory

    Ten out of the 25 most frequently detected groundwater contaminants at hazardous waste sites are chlorinated volatile organic compounds (VOCs) 1. Trichloroethylene (TCE) and tetrachloroethylene (PCE) are among the top three 1. Granular activated carbon (GAC) adsorption is widel...

  2. COMMUNICATION TO THE EDITOR Aerobic Degradation of Mixtures of

    E-print Network

    Wood, Thomas K.

    (TCE) INTRODUCTION Both tetrachloroethylene (PCE) and trichloroethylene (TCE) are suspected carcinogens carcinogen (McCarty, 1997). Both VC and cis-DCE are U.S. Environmental Protection Agency priority pollut carcinogen (Mc- Clay et al., 1996). Because of this ecological risk posed by soil and water contaminated

  3. A multidisciplinary approach to toxicological screening: III. Neurobehavioral toxicity

    Microsoft Academic Search

    Virginia C. Moser; Billie M. Cheek; Robert C. MacPhail

    1995-01-01

    The neurobehavioral effects of 10 known toxicants were examined as part of a multidiscipli?nary screening battery. The toxicants included carbaryl (CAR), triadimefon (TDM), heptachlor (HEP), chlordane (CDN), diethylhexyl phthalate (DEHP), carbon tetrachloride (CCI4), phenol, trichloroethylene (TCE), tetrachloroethylene (PER or perchlorethylene), and dichloromethane (DCM or methylene chloride). A functional observational battery and motor activity measurements were conducted before exposure, at specified

  4. The dependence of nonthermal plasma behavior of VOCs on their chemical structures

    Microsoft Academic Search

    S. Futamura; A. H. Zhang; T. Yamamoto

    1997-01-01

    The dependence of nonthermal plasma behavior of volatile organic compounds (VOCs) on their chemical structures was investigated, using methane, ethane, ethylene, butane, 1,1,2-trichloroethane, trichloroethylene, and tetrachloroethylene as target VOCs. It has been shown that the above VOCs decompose homolytically via their excited states, irrespective of their electron affinities. Efficiencies of energy transfer from hot electrons to the VOCs could be

  5. Anionic surfactant remediation of soil columns contaminated by nonaqueous phase liquids

    Microsoft Academic Search

    V. Dwarakanath; K Kostarelos; Gary A Pope; Doug Shotts; William H Wade

    1999-01-01

    A variety of column experiments have been completed for the purpose of selecting and evaluating suitable surfactants for remediation of nonaqueous phase liquids (NAPLs). The various NAPLs tested in the laboratory experiments were tetrachloroethylene (PCE), trichloroethylene (TCE), jet fuel (JP4) and a dense nonaqueous phase liquid from a site at Hill Air Force Base, UT. Both Ottawa sand and Hill

  6. In-situ characterization using pulsed laser systems and hyperspectral imaging

    Microsoft Academic Search

    Rosemarie Catherine Chinni

    2002-01-01

    We are investigating the use of resonance-enhanced multiphoton ionization (REMPI) to detect volatile organic compounds (VOCs) mainly BTEX compounds (benzene, toluene, ethylbenzene, o-, m -, and p-xylenes) and some organochlorides, such as tetrachloroethylene (PCE), trichloroethylene (TCE), and carbon tetrachloride, found in the environment. The long term objective of this work is to develop a system for measuring and identifying a

  7. MEASUREMENT OF PERCHLOROETHYLENE IN AMBIENT AIR

    EPA Science Inventory

    Perchloroethylene (i.e., tetrachloroethylene) is an organic solvent widely used in dry cleaning and industrial metal degreasing operations. Short-term field studies were conducted in each of three major metropolitan areas which were selected on the basis of the number, density an...

  8. Heat recovery by organic Rankine cycle in ceramics firing ovens. Final report

    Microsoft Academic Search

    G. Angelino; P. Ferrari; M. Gaia; G. Giglioli; E. Macchi

    2008-01-01

    The process of ceramics firing, like many other high temperature processes, is inefficient but it is possible to recover an important fraction of the heat input. A recovery system is proposed which transforms the recovered heat into electricity by means of an organic Rankine cycle engine. A thermodynamic study has led to the selection of tetrachloroethylene as the working fluid,

  9. Anaerobic biotransformations of pollutant chemicals in aquifers

    Microsoft Academic Search

    Joseph M. Suflita; Susan A. Gibson; Ralph E. Beeman

    1988-01-01

    Summary Anaerobic microbial communities sampled from either a methanogenic or sulfate-reducing aquifer site have been tested for their ability to degrade a variety of groundwater pollutants, including halogenated aromatic compounds, simple alkyl phenols and tetrachloroethylene. The haloaromatic chemicals were biodegraded in methanogenic incubations but not under sulfate-reducing conditions. The primary degradative event was typically the reductive removal of the aryl

  10. Chlorination byproducts induce gender specific autistic-like behaviors in CD1 mice

    Microsoft Academic Search

    Sara Rose Guariglia; Edmund C. Jenkins; Kathryn K. Chadman; Guang Y. Wen

    In 2000, the Agency for Toxic Substances and Disease Registry (ATSDR) released a report concerning elevated autism prevalence and the presence water chlorination byproducts in the municipal drinking water supply in Brick Township, New Jersey. The ATSDR concluded that it was unlikely that these chemicals, specifically chloroform, bromoform (Trihalomethanes; THMs) and tetrachloroethylene (Perchloroethylene; PCE) had contributed to the prevalence of

  11. Historical review on development of environmental quality standards and guideline values for air pollutants in Japan

    Microsoft Academic Search

    Toshihiro Kawamoto; Thi-Thu-Phuong Pham; Takayuki Matsuda; Tsunehiro Oyama; Masayuki Tanaka; Hsu-Sheng Yu; Iwao Uchiyama

    2011-01-01

    Environmental quality standards (EQSs) have been established as desirable levels to be maintained for protection of human health and the conservation of the living environment by Basic Environment Law. EQSs in ambient air had been set for 10 substances (sulfur dioxide (SO2), carbon monoxide (CO), suspended particulate matter (SPM), nitrogen dioxide (NO2) and photochemical oxidants (Ox), benzene, tetrachloroethylene, trichloroethylene, dioxins

  12. COMPLETE NATURAL ATTENUATION OF PCE AND TCE WITHOUT VINYL CHLORIDE AND ETHENE ACCUMULATION

    EPA Science Inventory

    A shallow aquifer at the Twin Cities Army Ammunition Plant (TCAAP) was contaminated with tetrachloroethylene (PCE) and trichloroethylene (TCE). Cisdichloroethylene (cis-DCE) is found in ground water at the site, indicating that reductive dehalogenation of PCE and TCE is occurrin...

  13. OXIDATION OF WATER SUPPLY REFRACTORY SPECIES BY OZONE WITH ULTRAVIOLET RADIATION

    EPA Science Inventory

    The use of ozone with ultraviolet radiation was studied as an advanced treatment process for the removal of micropollutants and trihalomethane precursors from drinking water. The model compounds chloroform, bromo-dichloromethane, tetrachloroethylene and 2,2',4,4',6,6'-hexachlorob...

  14. Effects of solid concentration on the partition of volatile organic compounds with soils

    Microsoft Academic Search

    J. C. Huang; B. A. Dempsey; S. Y. Chang; H. Ganjidoost

    1987-01-01

    The rate and equilibrium of adsorption of trichloroethane, trichloroethylene and tetrachloroethylene by different soil materials were examined. The specific goals were to: measure the rates of adsorption and desorption; establish the adsorption isotherms and the partition coefficients for different VOC-soil combinations; determine the effect of solid concentration on the partition of VOC with soils; and evaluate the phenomenon of competitive

  15. Health assessment for Delta Quarries/Stotler Landfill, Antis/Logan Township, Blair County, Pennsylvania, Region 3. CERCLIS No. PAD981038052. Preliminary report

    SciTech Connect

    Not Available

    1988-11-15

    The Delta Quarries (Stotler Landfill) site is an inactive, unpermitted municipal waste facility which operated from the 1960s until 1985. The environmental contamination on-site consists of trans-1,2-dichloroethylene, trichloroethylene, and 1,1-dichloroethane in groundwater. In addition, lead was detected in groundwater during one sampling event. The environmental contamination off-site consists of trichloroethylene, tetrachloroethylene, and 1,1,1-trichloroethane in surface water; and tetrachloroethylene in groundwater. The off-site groundwater contamination was found in a residential well and in a spring. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via contaminated groundwater and surface water.

  16. Critical contaminant/critical pathway analysis - surface water transport for nonradioactive contaminants

    SciTech Connect

    Chen, Kuo-Fu

    1996-11-01

    The health risks for an individual exposed to contaminants released from SRS outfalls from 1989 to 1995 were estimated. The exposure pathways studied are ingestion of drinking water, ingestion of contaminated fish and dermal contact with contaminants in water while swimming. The estimated incremental risks for an individual developing cancer vary from 3.E-06 to 1.0E-05. The estimated total exposure chronic noncancer hazard indices vary from 6.E-02 to 1.E-01. The critical contaminants were ranked based on their cancer risks and chronic noncarcinogenic hazard quotients. For cancer risks, the critical contaminants released from SRS outfalls are arsenic, tetrachloroethylene, and benzene. For chronic noncarcinogenic risks, the critical contaminants released from srs outfalls are cadmium, arsenic, silver, chromium, mercury, selenium, nitrate, manganese, zinc, nickel, uranium, barium, copper, tetrachloroethylene, cyanide, and phenol. The critical pathways in decreasing risk order are ingestion of contaminated fish, ingestion of drinking water and dermal contact with contaminants in water while swimming.

  17. Effects of dietary polychlorinated biphenyls and polybrominated biphenyls on the renal and hepatic toxicities of several chlorinated hydrocarbon solvents in mice

    Microsoft Academic Search

    W. M. Kluwe; C. L. Herrmann; J. B. Hook

    1979-01-01

    Male ICR mice were fed a control diet or the same diet supplemented with 100 ppm polybrominated biphenyl (PBB) or 200 ppm polychlorinated biphenyl (PCB) for 28 d before single ip injections of various quantities of trichloroethylene (TRI), tetrachloro?ethylene (TET), 1,1,2?trichloroethane (TCE), or carbon tetrachloride (CCI4). The ratio of liver weight to body weight was increased by dietary PBB and

  18. Genotoxic effects of chemicals in the single cell gel (SCG) test with human blood cells in relation to the induction of sister-chromatid exchanges (SCE)

    Microsoft Academic Search

    Andreas Hartmann; Günter Speit

    1995-01-01

    In a comparative study, henzo[a]pyrene (BaP), cyclophosphamide (CP), N-methyl-N?-nitro-N-nitrosoguanidine (MNNG) and tetrachloroethylene (PER) were tested for their ability to induce genotoxic effects in the single cell gel (SCG) test and the sister-chromatid exchange (SCE) test with human blood cells. MNNG as well as S9 mix activated BaP- and CP-induced DNA effects in both tests in a dose-dependent manner. While the

  19. Distribution of selected volatile organic compounds determined with water-to-vapor diffusion samplers at the interface between ground water and surface water, Centredale Manor site, North Providence, Rhode Island, September 1999

    USGS Publications Warehouse

    Church, Peter E.; Lyford, Forest P.; Clifford, Scott

    2000-01-01

    Volatile organic compounds are present in soils and ground water at the Centredale Manor Superfund Site in North Providence, Rhode Island. In September 1999, water-to-vapor diffusion samplers were placed in the bottom sediments of waterways adjacent to the site to identify possible contaminated ground-water discharge areas. The approximate12-acre site is a narrow stretch of land between the eastern bank of the Woonasquatucket River, downstream from the U.S. Route 44 bridge and a former mill raceway. The samplers were placed along a 2,250-foot reach of the Woonasquatucket River, in the former mill raceway several hundred feet to the east and parallel to the river, and in a cross channel between the river and former mill raceway. Volatile organic compounds were detected in 84 of the 104 water-to-vapor diffusion samplers retrieved. Trichloroethylene and tetrachloro-ethylene were the principal volatile organic compounds detected. The highest vapor concentrations measured for these two chemicals were from diffusion samplers located along an approximate 100-foot reach of the Woonasquatucket River about 500 feet downstream of the bridge; here trichloroethylene and tetrachloroethylene vapor concentrations ranged from about 2,000 to 180,000 and 1,600 to 1,400,000 parts per billion by volume, respectively. Upstream and downstream from this reach and along the former mill raceway, trichloroethylene and tetrachloroethylene vapor concentrations from the diffusion samples were generally less than 100 parts per billion by volume. Along the lower reaches of the river and mill raceway, however, and in the cross channel, vapor concentrations of trichloroethylene exceeded 100 parts per billion by volume and tetrachloroethylene exceeded 1,000 parts per billion by volume in several diffusion samples. Although diffusion sample vapor concentrations are higher than water concentrations in surface waters and in ground water, and they should only be interpreted qualitatively as relative values, these values provide important information as to potential discharge areas of contaminants.

  20. Stability of nitrate-ion in simulated deposition samples used for quality-assurance activities by the U. S. Geological Survey

    Microsoft Academic Search

    D. A. V. Eckhardt; K. A. Pearsall

    1989-01-01

    Trichloroethylene (TCE), 1,2-dichloroethylene (DCE), and tetrachloroethylene (PCE) have been detected in water from five public-supply wells and six cooling-water wells that tap the Magothy aquifer at Roosevelt Field. The cooling water is discharged after use to the water table aquifer through a nearby recharge basin and a subsurface drain field. Three plumes of TCE in groundwater have been delineated -

  1. Landfill gas (LFG) processing via adsorption and alkanolamine absorption

    Microsoft Academic Search

    Ankur Gaur; Jin-Won Park; Sanjeev Maken; Ho-Jun Song; Jong-Jin Park

    2010-01-01

    Landfill gas (LFG) was upgraded to pure methane using the adsorption and absorption processes. Different toxic compounds like aromatics and chlorinated compounds were removed using granular activated carbon. The activated carbon adsorbed toxic trace components in the following order: carbon tetrachloride>toluene>chloroform>xylene>ethylbenzene>benzene>trichloroethylene?tetrachloroethylene. After removing all trace components, the gas was fed to absorption apparatus for the removal of carbon dioxide (CO2).

  2. Evaluation of volatile chlorinated hydrocarbons distribution along depth profiles in the Ross Sea, Antarctica

    Microsoft Academic Search

    Lelio Zoccolillo; Carlo Abete; Claudia Cafaro; Susanna Insogna

    2009-01-01

    The presence and the distribution along depth profiles of volatile chlorinated hydrocarbons (VCHCs) were evaluated in seawater samples collected in the Ross Sea (Southern Ocean, Antarctica) during the 2002-2003 Italian expedition. Sampling areas were located where the Circumpolar Deep Water interacts with the shelf waters that supply the Ross Sea.The VCHCs investigated were: 1,1,1-trichloroethane (C2H3Cl3), tetrachloromethane (CCl4), trichloroethylene (C2HCl3), tetrachloroethylene

  3. Aerobic microorganism for the degradation of chlorinated aliphatic hydrocarbons

    SciTech Connect

    Fliermans, C.B.

    1988-10-12

    This invention pertains to a chlorinated aliphatic hydrocarbon-degrading microorganism, having American Type Culture Collection accession numbers ATCC 53570 and 53571, in a biologically pure culture aseptically collected from a deep subsurface habitat and enhanced, mineralizes trichloroethylene and tetrachloroethylene to HCl, H{sub 2}O and CO{sub 2} under aerobic conditions stimulated by methane, acetate, methanol, tryptone-yeast extract, propane and propane-methane.

  4. Evaluation of a passive sampler for volatile organic compounds at ppb concentrations, varying temperatures, and humidities with 24-h exposures. 2. Sampler performance

    Microsoft Academic Search

    Chih-Wen Chung; Maria T. Morandi; Thomas H. Stock; Masoud Afshar

    1999-01-01

    The performance of the 3M 3520 organic vapor monitor (OVM) as a tool for monitoring inhalation exposures to volatile organic compounds (VOCs) in nonoccupational community environments was evaluated by using combined controlled test atmospheres of benzene, 1,3-butadiene, carbon tetrachloride, chloroform, 1,4-dichlorobenzene, methylene chloride, styrene, tetrachloroethylene, and toluene. Eight OVMs were simultaneously exposed to concentrations of 10,20, and 200 μg\\/m³ in

  5. Evaluation of a passive sampler for volatile organic compounds at ppb concentrations, varying temperatures, and humidities with 24-h exposures. 1. Description and characterization of exposure chamber system

    Microsoft Academic Search

    Chih-Wen Chung; Maria T. Morandi; Thomas H. Stock; Masoud Afshar

    1999-01-01

    A dynamic exposure chamber was constructed to evaluate the performance of the 3M 3520 organic vapor monitor when exposed during 24 h to combined test atmospheres of benzene, 1,3-butadiene, carbon tetrachloride, chloroform, 1,3-dichlorobenzene, methylene chloride, styrene, tetrachloroethylene, and toluene at target concentrations of 10, 20, and 200 μg\\/m³ in combination with temperatures of 10, 25, and 40 C and relative

  6. Preparation and characterization of polyurea microcapsules containing colored electrophoretic responsive fluid

    Microsoft Academic Search

    G. Li; Y. Q. Feng; X. G. Li; P. Gao; J. Wang; J. Y. Xie

    2007-01-01

    A kind of yellow–red microencapsulated electronic ink was prepared by interfacial polymerization. The shell of the polyurea\\u000a (PU) microcapsules was fabricated from tolyene 2,4-diisocyanate (TDI) and triethylene tetraamine (TETA). Pigment Hansa Yellow\\u000a 10G, as negatively charged electrophoretic particles, was homodispersed in tetrachloroethylene (TCE)\\/cyclohexane mixture to\\u000a make the suspending fluid core. And Oil Red was also added in the core to

  7. The electric response behavior and microencapsulation of the pigment phthalocyanine green G using interfacial polymerization

    Microsoft Academic Search

    Haiyan Mao; Chaoxia Wang; Chunxia Wang; Kairui Zhang; Shaohai Fu

    The polyamide microcapsules for the electrophoretic display have been prepared via interfacial polymerization. The core material\\u000a of the microcapsules is electrophoretic fluid consisted of pigment phthalocyanine green G (CAS No. 1328-53-6) modified with\\u000a octadecylamine, tetrachloroethylene, and polyoxyethylene octylphenol ether (OP-10). The wall of the polyamide is synthesized\\u000a from paraphthaloyl chloride and diethylenetriamine. FT-IR indicated that octadecylamine was bonded to pigment

  8. Alcohol-free diphenyl oxide disulfonate middle-phase microemulsion systems

    Microsoft Academic Search

    Bin Wu; Jeffrey H. Harwell; David A. Sabatini; Jason D. Bailey

    2000-01-01

    Diphenyl oxide disulfonate (DPDS) surfactants were successfully used to formulate Winsor Type III middlephase microemulsion\\u000a systems with tetrachloroethylene (PCE) and decane. To our knowledge this is the first time that monochain DPDS surfactant\\u000a phenyloxide monohexadecyl disulfonate surfactant (C16MADS) and commercially available DOWFAX 8390 were found to form middle-phase\\u000a microemulsion systems with oils. Hydrophobic dioctyl sodium sulfosuccinate (Aerosol OT) was also

  9. H-Area Seepage Basins groundwater monitoring report. First quarter 1992

    SciTech Connect

    Thompson, C.Y.

    1992-06-01

    During first quarter 1992, tritium, nitrate, nonvolatile beta, total alpha-emitting radium (radium-224 and radium-226), gross alpha, antimony, mercury, lead, tetrachloroethylene, arsenic, and cadmium exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the H-Area Seepage Basins (HASB) at the Savannah River Site. This report presents and discusses the groundwater monitoring results in the H-Area for first quarter 1992.

  10. Formation of chlorinated acetic acids during UV\\/H 2O 2-oxidation of ground water contaminated with chlorinated ethylenes

    Microsoft Academic Search

    Arja Hirvonen; Tuula Tuhkanen; Pentti Kalliokoski

    1996-01-01

    The performance of the UV\\/H2O2 process for purification of ground water contaminated with tri- and tetrachloroethylene was studied by measuring the formation of chloroacetic acids during treatment. UV\\/H2O2 oxidation has previously given good purification results and the aim of this study was to investigate the importance of potentially harmful by-products formed in the purification process. The rate of formation of

  11. EXTRACTION OF AMERICIUM(III) FROM CHLORIDE MEDIA BY OCTYL(PHENYL)-N,N-DIISOBUTYLCARBAMOYLMETHYLPHOSPHINE OXIDE

    Microsoft Academic Search

    E. Philip Horwitz; Herbert Diamond; Kathleen A. Martin; Renato Chiarizia

    1987-01-01

    The extraction of Am(III) from chloride media was studied using octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide, O? D(iB)CMPO or CMPO, dissolved in tetrachloroethylene. Although the extraction of Am(III) by 0?D(iB)CMPO is many orders of magnitude weaker from chloride than nitrate media, the rapid Increase in the mean activity of chloride in HC1 and in most soluble chloride salts with concentration makes extraction from moderate

  12. EXTRACTION OF Am FROM NITRIC ACID BY CARBAMOYL-PHOSPHORYL EXTRACTANTS: THE INFLUENCE OF SUBSTITUENTS ON THE SELECTIVITY OF Am OVER Fe AND SELECTED FISSION PRODUCTS

    Microsoft Academic Search

    E. Philip Horwltz; Kathleen A. Martin; Herbert Diamond; Louis Kaplan

    1986-01-01

    A number of neutral extractants containing the P(0)(CH2)nC(0)N raolety were evaluated for their ability to extract Am from nitric acid and their selectivity for Am over Fe and selected fission products. Extractants containing alkoxy, alkyl, and aryl substltuents were evaluated. Tetrachloroethylene was used as a diluent. Fission products selected for study were Y, Zr, Mo, Tc, Ru, Rh, Pd, La,

  13. Adsorption from aqueous solutions of chlorinated organic compounds onto activated carbons

    Microsoft Academic Search

    Anna Bembnowska; Robert Pe?ech; Eugeniusz Milchert

    2003-01-01

    The adsorption capacities of five chlorinated organic compounds, chloroform (CHCl3), 1,1,2,2-tetrachloroethane (S-TET), 1,1,2,2-tetrachloroethylene (PER), 1,2-dichloropropane (DCP), and bis(1-chloroisopropyl) ether (BCIPE) for DTO, WD-EXTRA, and AG-5 activated carbons were investigated. Moreover, the effective molecular diameters of investigated chlorocompounds were calculated. The Freundlich and Langmuir equations of adsorption isotherms describe the experimental data with good correlation for each studied system. The equilibrium

  14. Molecular Inclusion Properties of Hydrophobic Organic Compounds by a Modified ?-Cyclodextrin Intercalated within a Layered Double Hydroxide

    Microsoft Academic Search

    Hongting Zhao; George F. Vance

    1998-01-01

    A study was conducted to evaluate the inclusion properties of various nonionic hydrophobic organic compounds by a novel intercalate derived from magnesium-aluminum layered double hydroxide (Mg\\/Al LDH) and carboxymethyl-ß-cyclodextrin with a degree of substitution of 3 [CMCD(3)]. The isotherm sorption results at 25 °C showed that the CMCD(3)-Mg\\/Al LDH intercalate could retain all the organic compounds (trichloroethylene, tetrachloroethylene, benzene, toluene,

  15. Henry's law constants and micellar partitioning of volatile organic compounds in surfactant solutions

    Microsoft Academic Search

    Leland M. Vane; Eugene L. Giroux

    2000-01-01

    Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor-liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace experiments were performed to quantify the effect of four anionic surfactants and one nonionic surfactant on the Henry's law constants of 1,1,1-trichloroethane, tirchloroethylene, toluene, and tetrachloroethylene

  16. Mode of zeolite catalysts deactivation during chlorinated VOCs oxidation

    Microsoft Academic Search

    M. Guillemot; J. Mijoin; S. Mignard; P. Magnoux

    2007-01-01

    The catalytic oxidation of tetrachloroethylene (PCE), chosen as model for chlorinated hydrocarbons, was investigated over Pt\\/HY, Pt\\/NaY and Pt\\/NaX under humid conditions at a space velocity of 15,300h?1. PCE is selectively transformed into carbon dioxide (CO2) and hydrochloric acid (HCl) over all catalysts studied in this work. 1.2%Pt\\/HY exhibits the highest activity with the complete conversion of PCE at 500°C

  17. Contamination of shallow ground water in the area of building 95, Picatinny Arsenal, New Jersey, 1985-90

    USGS Publications Warehouse

    Sargent, B.P.; Storck, D.A.

    1994-01-01

    A zone of contaminated ground water at Picatinny Arsenal has resulted from the operation of a metal- plating facility in building 95 during 1960-81, and the wastewater-treatment system that is in and adjacent to the building. Thirty-two monitoring wells were installed in 1989 to supplement 12 previously installed wells. All wells were sampled in 1989 and 1990 for analysis of ground water for inorganic constituents, trace elements, volatile organic compounds, and nutrients. Four wells also were sampled for analysis for base/neutral- and acid-extractable compounds and pesticides, and soil gas from the unsaturated zone at eight sites was analyzed for volatile organic compounds. Concentrations of dissolved solids and sulfate in the study area were consistently above the U.S. Environmental Protection Agency's secondary drinking-water regulations. The areal distribution of sulfate differed from that of the volatile organic compounds. Concentrations of trace elements were not elevated downgradient from the source. The estimated average velocity of contaminant movement is 0.1 to 1.1 feet per day. The major organic contaminants identified in the study area are trichloroethylene, tetrachloroethylene, and 1,1,1-trichloroethane. Trichloroethylene was detected in wells upgradient from the wastewater- treatment site. Tetrachloroethylene and 1,1,1-trichloroethane might originate at tanks in the basement of building 95 rather than at the adjacent wastewater-treatment system. The pre- dominant gas-phase contaminant, 1,1,1- trichloroethane, was detected at a maximum con- centration of 15.7 micrograms per liter. Both trichoroethylene and tetrachloroethylene were detected in concentrations greater than 0.10 micrograms per liter in five of the eight soil- gas samples, indicating that volatilization and diffusion through the unsaturated zone could be a significant mechanism of contaminant loss from the aquifer.

  18. An ion mobility spectrometer sensor system for subsurface use

    Microsoft Academic Search

    Daniella Morgos; Ivan Geroy; Richard G. Sevier; Molly M. Gribb; Kevin P. Ryan; Herbert H. Hill

    2010-01-01

    An ion mobility spectrometer (IMS) probe system for real-time, subsurface soil-gas sampling applications is presented. The\\u000a system includes an IMS and supporting electronics encased in a 51 mm diameter stainless steel probe housing. The IMS was challenged\\u000a in the laboratory with 2,6-di-tert-butylpyridine (DtBP) and tetrachloroethylene (PCE) in zero air yielding reduced ion mobility\\u000a constants (Ko) values of 1.42 cm2\\/Vs (n?=?3) and 1.79?±?0.01 cm2\\/Vs

  19. Operations Support of Phase 2 Integrated Demonstration In Situ Bioremediation. Volume 4, Final report: Averaged data in tabular form, Disks 3,4; Averaged data in graphical form, Disks 1,2,3,4

    SciTech Connect

    Hazen, T.C. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1993-09-01

    This report contains experimental data collected during the demonstration of in situ bioremediation at the Savannah River Site. This project was designed to demonstrate in situ bioremediation of ground water and sediment contaminated with chlorinated solvents. Indigenous microorganisms were stimulated to degrade trichloroethylene, tetrachloroethylene, and their daughter products in situ by addition of nutrients to the contaminated aquifer and adjacent vadose zone. The principle carbon/energy source nutrient used in this demonstration was methane. In situ biodegradation is a highly attractive technology for remediation because contaminants are destroyed, not simply moved to another location or immobilized, thus decreasing costs, risks, and time, while increasing efficiency, safety, and public and regulatory acceptability.

  20. Health assessment for Newcastle Abandoned Container Site, Newcastle, Delaware, Region 3. CERCLIS No. DED058980442. Preliminary report

    SciTech Connect

    Not Available

    1988-11-15

    The Newcastle Abandoned Container site is listed on the National Priorities List. On February 28, 1986, radioactive, corrosive, and toxic materials, and a large number of containers filled with unknown material, were inventoried, containerized, and removed. On-site contamination consists of polychlorinated biphenyls, trichloroethylene, creosote, chloroform, and di-n-butylphthalate in soil; and tetrachloroethylene, acetone, xylene, trichlorofluoromethane, trichloroethylene, and tris(betachloroisopropyl)phosphate in groundwater. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via groundwater. The potential for contamination of the lower aquifer should be investigated.

  1. Intermedia transfer factors for fifteen toxic pollutants released to air basins in California

    SciTech Connect

    McKone, T.E.; Daniels, J.I. [Lawrence Livermore National Lab., CA (United States); Chiao, F.F.; Hsieh, D.P.H. [Univ. of California, Davis, CA (United States)

    1993-10-01

    This report provides a summary definition of the intermedia-transfer factors (ITFs). Methods are discussed for estimating these parameters in the absence of measured values, and the estimation errors inherent in these estimation methods are considered. A detailed summary is provided of measured and estimated ITF values for fifteen air contaminants. They include: 1,3 butadiene; cadmium; cellosolve; cellosolve acetate; chloroform; di-2-ethylhexylphthalate; 1,4-dioxame; hexachlorobenzene; inorganic arsenic; inorganic lead; nickel; tetrachloroethylene; toluene; toluene-2,4-diisocyanate; and 1,3-xylene. Recommendations are made regarding the expected value and variance in these values for use in exposure models.

  2. Nonaqueous low-temperature nitration of uranium oxides in TBP

    Microsoft Academic Search

    A. Yu. Kuznetsov; E. P. Buchikhin; V. V. Solov’eva; A. M. Chekmarev

    2008-01-01

    Nonaqueous low-temperature nitration of UO2 and U3O8 in the system TBP-chlorinated dilu-ent-NO2 was studied. The oxides dissolve to form uranyl nitrate. The influence exerted on the dissolution efficiency by the concentration\\u000a of the donor solvent in the TBP-tetrachloroethylene system and by additions of water was examined. These dependences pass\\u000a through a maximum. The influence of temperature on nitration of U3O8

  3. Radiation induced dechlorination of some chlorinated hydrocarbons in aqueous suspensions of various solid particles

    NASA Astrophysics Data System (ADS)

    Mú?ka, V.; Bu?ata, M.; ?uba, V.; Silber, R.; Juha, L.

    2015-07-01

    Radiation induced dechlorination of trichloroethylene (TCE) and tetrachloroethylene (PCE) in aqueous solutions containing the active carbon (AC) or cupric oxide (CuO) as the modifiers was studied. The obtained results were compared to the previously studied dechlorination of polychlorinated biphenyls (PCBs). Both modifiers were found to decrease the efficiency of dechlorination. The AC modifier acts mainly via adsorption of the aliphatic (unlike the aromatic) hydrocarbons and the CuO oxide mainly inhibits the mineralization of the perchloroethylene. The results presented in this paper will be also helpful for the studies of the impact of chlorinated hydrocarbons on the membrane permeability of living cells.

  4. Mixed Waste Management Facility (MWMF) groundwater monitoring report. Second quarter 1993

    SciTech Connect

    Not Available

    1993-09-01

    Groundwater monitoring continued at the Savannah River Plant. During second quarter 1993, nine constituents exceeded final Primary Drinking Water Standards in groundwater samples from downgradient monitoring wells at the Mixed Waste Management Facility, the Old Burial Ground, the E-Area Vaults, and the proposed Hazardous Waste/Mixed Waste Disposal Vaults. As in previous quarters, tritium and trichloroethylene were the most widespread constituents. Chloroethene (vinyl chloride), dichloromethane (methylene chloride), 1,1-dichloroethylene, gross alpha, lead, nonvolatile beta, or tetrachloroethylene also exceeded standards in one or more wells. The groundwater flow directions and rates in the three hydrostratigraphic units were similar to those of previous quarters.

  5. Intelligent Unmanned Monitoring of Remediated Sites

    SciTech Connect

    Emile Fiesler, Ph.D.

    2001-06-01

    During this Phase I project, IOS demonstrated the feasibility of combining digital signal processing and neural network analysis to analyze spectral signals from pure samples of several typical contaminants. We fabricated and tested a prototype system by automatically analyzing Raman spectral data taken in the Vadose zone at the 321 M site in the M area of DOE's Savannah River Site in South Carolina. This test demonstration proved the ability of IOS's technology to detect the target contaminants, tetrachloroethylene (PCE) and trichloroethylene (TCE), in isolation, and to detect the spectra of these contaminants in real-world noisy samples taken from a mixture of materials obtained from this typical remediation target site.

  6. Desorption Behavior of Trichloroethene and Tetrachloroethene in U.S. Department of Energy Savannah River Site Unconfined Aquifer Sediments

    SciTech Connect

    Riley, Robert G.; Szecsody, Jim E.; Mitroshkov, Alexandre V.; Brown, Christopher F.

    2006-06-21

    The DOE Savannah River Site (SRS) is evaluating the potential applicability of the monitored natural attenuation (MNA) process as a contributor to the understanding of the restoration of its unconfined groundwater aquifer known to be contaminated with the chlorinated hydrocarbon compounds trichloroethylene (TCE) and tetrachloroethylene (PCE). This report discusses the results from aqueous desorption experiments on SRS aquifer sediments from two different locations at the SRS (A/M Area; P-Area) with the objective of providing technically defensible TCE/PCE distribution coefficient (Kd) data and data on TCE/PCE reversible and irreversible sorption behavior needed for further MNA evaluation.

  7. Biological degradation of VCCs and CFCs under simulated anaerobic landfill conditions in laboratory test digesters

    Microsoft Academic Search

    Anna Deipser; Rainer Stegmann

    1997-01-01

    The biological degradation of volatile halogenated hydrocarbons (chlorocarbons (VCCs) and chlorofluorocarbons (CFCs)) was\\u000a investigated under simulated conditions of landfills in laboratory test digesters. Fully halogenated VCCs (tetrachloroethylene,\\u000a 1,1,1-trichloroethane, tetrachloromethane and dichloromethane) and CFCs (trichlorofluoromethane (R11), dichlorodifluoromethane\\u000a (R12) and 1,1,2-trichlorotrifluoroethane (R113)) were degraded under anaerobic conditions in addition to the methanogenic\\u000a bacteria in municipal solid waste (MSW) and organic wastes. These

  8. Henry's law constants and micellar partitioning of volatile organic compounds in surfactant solutions

    SciTech Connect

    Vane, L.M.; Giroux, E.L.

    2000-02-01

    Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor-liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace experiments were performed to quantify the effect of four anionic surfactants and one nonionic surfactant on the Henry's law constants of 1,1,1-trichloroethane, tirchloroethylene, toluene, and tetrachloroethylene at temperatures ranging from 30 to 60 C. Although the Henry's law constant increased markedly with temperature for all solutions, the amount of VOC in micelles relative to that in the extramicellar region was comparatively insensitive to temperature. The effect of adding sodium chloride and isopropyl alcohol as consolutes also was evaluated. Significant partitioning of VOCs into miscelles was observed, with the micellar partitioning coefficient (tendency to partition from water into mecelle) increasing according to the following series: trichloroethane < trichloroethylene < toluene < tetrachloroethylene. The addition of surfactant was capable of reversing the normal sequence observed in Henry's law constants for these four VOCs.

  9. Mixed Waste Management Facility groundwater monitoring report. Second quarter 1994

    SciTech Connect

    Chase, J.A.

    1994-09-01

    Currently, 125 wells monitor groundwater quality in the uppermost aquifer beneath the Mixed Waste Management Facility (MWMF) at the Savannah River Site. Samples from the wells are analyzed for selected heavy metals, indicator parameters, radionuclides, volatile organic compounds, and other constituents. During second quarter 1994, chloroethene (vinyl chloride), 1,1-dichloroethylene, gross alpha, lead, tetrachloroethylene, trichloroethylene, or tritium exceeded final Primary Drinking Water Standards (PDWS) in approximately half of the downgradient wells at the MWMF. Consistent with historical trends, elevated constituent levels were found primarily in Aquifer Zone. As in previous quarters, tritium and trichloroethylene were the most widespread elevated constituents during second quarter 1994. Sixty-two of the 125 monitoring wells contained elevated tritium activities. Trichloroethylene concentrations exceeded the final PDWS in 23 wells. Chloroethene, 1,1-dichloroethylene, lead, and tetrachloroethylene, elevated in one or more wells during second quarter 1994, also occurred in elevated levels during first quarter 1994. These constituents generally were elevated in the same wells during both quarters. Gross alpha, which was not elevated in any well during first quarter 1994, was elevated in one well during second quarter. Copper, mercury, and nonvolatile beta were elevated during first quarter 1994 but not during second quarter.

  10. Mixed Waste Management Facility (MWMF) Groundwater Monitoring Report: Fourth quarter 1991 and 1991 summary

    SciTech Connect

    Thompson, C.Y.

    1992-03-01

    During fourth quarter 1991, tritium, trichloroethylene, tetrachloroethylene, chloroethene (vinyl chloride), total radium, mercury, and lead exceeded the US Environmental Protection Agency primary drinking water standards (PDWS) in groundwater samples from monitoring wells at the Mixed Waste Management Facility (MWMF) and adjacent facilities. Tritium and trichloroethylene were the most widespread contaminants; 55 (49%) wells exhibited elevated tritium activities, and 24 (21%) wells exhibited elevated trichloroethylene concentrations. Tritium and trichloroethylene levels exceeding the PDWS also occurred in several wells in Aquifer Unit IIA (Congaree). Levels of manganese, total organic halogens, nickel, iron, 1,1-dichloroethane, aluminum, nonvolatile beta, and trichlorofluoromethane that exceeded Flag 2 criteria were found in one or more wells beneath the MWMF. Downgradient wells in the three hydrostratigraphic units at the MWMF contained elevated levels of tritium, trichloroethylene, tetrachloroethylene, total radium, chloroethene (vinyl chloride), lead, mercury, manganese, total organic halogens, nickel, iron, 1,1-dichloroethane, aluminum, nonvolatile beta, or trichlorofluoromethane. Groundwater samples from 81 (72%) of the monitoring wells at the MWMF and adjacent facilities contained elevated levels of several contaminants.

  11. Mixed Waste Management Facility (MWMF) groundwater monitoring report, second quarter 1992

    SciTech Connect

    Not Available

    1992-09-01

    During second quarter 1992, tritium, trichloroethylene, tetrachloroethylene, chloroethene, antimony, 1,1-dichloroethylene, lead, nonvolatile beta, radium-228, thorium-228, or total alpha-emitting radium (radium-226 and radium-228) exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the Mixed Waste Management Facility (MWMF) and adjacent facilities. Tritium and trichloroethylene were the most widespread constituents; 55 (48%) of the 115 monitored wells contained elevated tritium activities, and 23 (20%) wells exhibited elevated trichloroethylene concentrations. Sixty-three downgradient wells screened in Aquifer Zone IIB2 (Water Table), Aquifer Zone IIB{sub 2} (Barnwell/McBean), and Aquifer Unit IIA (Congaree) contained concentrations of tritium, trichloroethylene, tetrachloroethylene, chloroethene, antimony, 1,1-dichloroethylene, lead, nonvolatile beta, radium-228, thorium-228, or total alpha-emitting radium that exceeded the PDWS during second quarter 1992. Upgradient wells BGO 1D and 2D and HSB 85A, 85B, and 85C did not contain any constituents that exceeded the PDWS.

  12. The influence of personal activities on exposure to volatile organic compounds

    SciTech Connect

    Wallace, L.A.; Pellizzari, E.D.; Hartwell, T.D.; Davis, V.; Michael, L.C.; Whitmore, R.W. (Environmental Protection Agency, Washington, DC (USA))

    1989-10-01

    Seven persons volunteered to perform 25 common activities thought to increase personal exposure to volatile organic chemicals (VOCs) during a 3-day monitoring period. Personal, indoor, and outdoor air samples were collected on Tenax cartridges three times per day (evening, overnight, and daytime) and analyzed by GC-MS for 17 target VOCs. Samples of exhaled breath were also collected before and after each monitoring period. About 20 activities resulted in increasing exposure to one or more of the target VOCs, often by factors of 10, sometimes by factors of 100, compared to exposures during the sleep period. These concentrations were far above the highest observed outdoor concentrations during the length of the study. Breath levels were often significantly correlated with previous personal exposures. Major exposures were associated with use of deodorizers (p-dichlorobenzene); washing clothes and dishes (chloroform); visiting a dry cleaners (1,1,1-trichloroethane, tetrachloroethylene); smoking (benzene, styrene); cleaning a car engine (xylenes, ethylbenzene, tetrachloroethylene); painting and using paint remover (n-decane, n-undecane); and working in a scientific laboratory (many VOCs). Continuously elevated indoor air levels of p-dichlorobenzene, trichloroethylene, 1,1,1-trichloroethane, carbon tetrachloride, decane, and undecane were noted in several homes and attributed to unknown indoor sources. Measurements of exhaled breath suggested biological residence times in tissue of 12-18 hr and 20-30 hr for 1,1,1-trichloroethane and p-dichlorobenzene, respectively.

  13. Evaluation of internal standards for the analysis of ignitable liquids in fire debris.

    PubMed

    Locke, Amanda K; Basara, Gene J; Sandercock, P Mark L

    2009-03-01

    An evaluation of eight compounds for use as an internal standard in fire debris analysis was conducted. Tests were conducted on tetrachloroethylene, chlorobenzene, n-octylbenzene, 3-phenyltolune, and deuterated compounds toluene-d8, styrene-d8, naphthalene-d8, and diphenyl-d10 to measure the extraction efficiency of each compound in the presence of an interfering volatile compound (carbon disulfide). Other tests were conducted to evaluate whether or not the presence of an ignitable liquid or pyrolysis/combustion products from fire debris would interfere with the identification of these compounds when used as an internal standard. The results showed that while any of the eight compounds could be used as an internal standard in fire debris analysis, the more volatile compounds (toluene-d8, tetrachloroethylene, chlorobenzene, and styrene-d8) showed better extraction efficiencies at room temperature than when heated to 60 degrees C. Each of the less volatile compounds (naphthalene-d8, diphenyl-d10, n-octylbenzene, and 3-phenyltolune) performed well during extraction at 60 degrees C, while naphthalene-d8 showed better extraction efficiency in the presence of competing volatiles when extracted at room temperature. PMID:19175707

  14. Health risk assessment of exposure to selected volatile organic compounds emitted from an integrated iron and steel plant.

    PubMed

    Chang, E-E; Wei-Chi, Wang; Li-Xuan, Zeng; Hung-Lung, Chiang

    2010-12-01

    Workplace air samples from sintering, cokemaking, and hot and cold forming processes in the integrated iron and steel industry were analyzed to determine their volatile organic compound (VOC) concentration. Sixteen VOC species including three paraffins (cyclohexane, n-hexane, methylcyclohexane), five chlorinated VOC species (trichloroethylene, 1,1,1-trichloroethane, tetrachloroethylene, chlorobenzene, 1,4-dichlorobenzene), and eight aromatics (benzene, ethylbenzene, styrene, toluene, m,p-xylene, o-xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene) were selected to measure their noncancer risk for workers. Concentrations of toluene, xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, dichlorobenzene, and trichloroethylene were high in all four processes. Carbon tetrachloride and tetrachloroethylene concentrations were high in the hot and cold forming processes. The noncancer risk followed the increasing order: cokemaking > sintering > hot forming > cold forming. 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene contributed 44% to 65% and 13% to 20% of noncancer risk, respectively, for the four processes. Benzene accounted for a high portion of the noncancer risk in cokemaking. The hazard index (HI: 17-108) of the average VOC concentrations suggests that health risks can be reduced by improving workplace air quality and protecting workers. PMID:20828338

  15. Characterization of nanocarbons (nanotubes and nanofibers) by Inverse Gas Chromatography

    NASA Astrophysics Data System (ADS)

    Díaz, E.; Ordóñez, S.; Vega, A.

    2007-04-01

    The adsorption of different alkanes (linear and cyclic), aromatics and chlorohydrocarbons on non-microporous carbons-carbon nanotubes (CNTs) and carbon nanofibres (CNFs)- was studied in this work by inverse gas chromatography (IGC). Capacity of adsorption was derived from the isotherms of adsorption, whereas thermodynamic properties (enthalpy of adsorption, surface free energy characteristics) have been determined from chromatographic retention data. CNTs present the highest adsorption capacity. From surface free energy data, enthalpies of adsorption of polar compounds were divided into dispersive and specific contributions. The interactions of cyclic (benzene and cyclohexane) and chlorinated compounds (trichloroethylene, tetrachloroethylene and chloroform) with the surfaces are mainly dispersive over all the carbons tested, being CNTs the material with the highest dispersive contribution. Adsorption parameters were correlated with morphological and chemical properties of the materials.

  16. Recovery of plutonium and americium from chloride salt wastes by solvent extraction

    SciTech Connect

    Reichley-Yinger, L.; Vandegrift, G.F.

    1987-01-01

    Plutonium and americium can be recovered from aqueous waste solutions containing a mixture of HCl and chloride salt wastes by the coupling of two solvent extraction systems: tributyl phosphate (TBP) in tetrachloroethylene (TCE) and octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in TCE. In the flowsheet developed, the salt wastes are dissolved in HCl, the Pu(III) is oxidized to the IV state with NaClO/sub 2/ and recovered in the TBP-TCE cycle, and the Am is then removed from the resultant raffinate by the CMPO-TCE cycle. The consequences of the feed solution composition and extraction behavior of these species on the process flowsheet design, the Pu-product purity, and the decontamination of the aqueous raffinate from transuranic elements are discussed. 16 refs., 6 figs.

  17. Comparison of temporal trends in VOCs as measured with PDB samplers and low-flow sampling methods

    USGS Publications Warehouse

    Harte, P.T.

    2002-01-01

    Analysis of temporal trends in tetrachloroethylene (PCE) concentration determined by two sample techniques showed that passive diffusion bag (pdb) samplers adequately sample the large variation in PCE concentrations at the site. The slopes of the temporal trends in concentrations were comparable between the two techniques, and the pdb sample concentration generally reflected the instantaneous concentration sampled by the low-flow technique. Thus, the pdb samplers provided an appropriate sampling technique for PCE at these wells. One or two wells did not make the case for widespread application of pdb samples at all sites. However, application of pdb samples in some circumstances was appropriate for evaluating temporal and spatial variations in VOC concentrations, thus, should be considered as a useful tool in hydrogeology.

  18. Survey of subsurface treatment technologies for environmental restoration sites at Sandia National Laboratories, New Mexico.

    SciTech Connect

    McGrath, Lucas K.; Ho, Clifford Kuofei; Wright, Jerome L.

    2003-08-01

    This report provides a survey of remediation and treatment technologies for contaminants of concern at environmental restoration (ER) sites at Sandia National Laboratories, New Mexico. The sites that were evaluated include the Tijeras Arroyo Groundwater, Technical Area V, and Canyons sites. The primary contaminants of concern at these sites include trichloroethylene (TCE), tetrachloroethylene (PCE), and nitrate in groundwater. Due to the low contaminant concentrations (close to regulatory limits) and significant depths to groundwater ({approx}500 feet) at these sites, few in-situ remediation technologies are applicable. The most applicable treatment technologies include monitored natural attenuation and enhanced bioremediation/denitrification to reduce the concentrations of TCE, PCE, and nitrate in the groundwater. Stripping technologies to remove chlorinated solvents and other volatile organic compounds from the vadose zone can also be implemented, if needed.

  19. Health assessment for Greenacres (Liberty Lake) Landfill, Spokane, Spokane County, Washington, Region 10. CERCLIS No. WAD980514608. Preliminary report

    SciTech Connect

    Not Available

    1988-08-09

    The Greenacres Landfill site is on the National Priorities List. The site is a 90-acre, rural-burning landfill that was closed in 1968. On-site contamination, determined by on-site ground water monitoring wells, consists of trans-1,2-dichloroethylene (41 ppb), chloroform (0.2 ppb), trichloroethylene (2 ppb), benzene (0.6 ppb), tetrachloroethylene (9 ppb), toluene (0.7 ppb), 2,4-dichlorophenoxyacetic acid (3 ppb), 2,4,5-trichlorophenoxyacetic acid (0.6 ppb), chromium (37 ppb), manganese (210 ppb), zinc (2,380 ppb), lead (67 ppb), barium 175 ppb, magnesium (18 ppb), and mercury (4 ppb). The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via the movement of contaminated ground water into an aquifer used as a public water source.

  20. Mixed Waste Management Facility groundwater monitoring report, First quarter 1994

    SciTech Connect

    Not Available

    1994-06-01

    During first quarter 1994, nine constituents exceeded final Primary Drinking Water Standards in groundwater samples from downgradient monitoring wells at the Mixed Waste Management Facility, the Old Burial Ground, the E-Area Vaults, the proposed Hazardous Waste/Mixed Waste Disposal Vaults, and the F-Area Sewage Sludge Application Site. As in previous quarters, tritium and trichloroethylene were the most widespread elevated constituents. Chloroethene (vinyl chloride), copper, 1,1-dichloroethylene, lead, mercury, nonvolatile beta, or tetrachloroethylene also exceeded standards in one or more wells. Elevated constituents were found in numerous Aquifer Zone IIB{sub 2} (Water Table) and Aquifer Zone IIB{sub 1}, (Barnwell/McBean) wells and in one Aquifer Unit IIA (Congaree) well. The groundwater flow directions and rates in the three hydrostratigraphic units were similar to those of previous quarters.

  1. Investigation of the behavior of VOCs in ground water across fine- and coarse-grained geological contacts using a medium-scale physical model

    SciTech Connect

    Hoffman, F.; Chiarappa, M.L.

    1998-03-01

    One of the serious impediments to the remediation of ground water contaminated with volatile organic compounds (VOCs) is that the VOCs are retarded with respect to the movement of the ground water. Although the processes that result in VOC retardation are poorly understood, we have developed a conceptual model that includes several retarding mechanisms. These include adsorption to inorganic surfaces, absorption to organic carbon, and diffusion into areas of immobile waters. This project was designed to evaluate the relative contributions of these mechanisms; by improving our understanding, we hope to inspire new remediation technologies or approaches. Our project consisted of a series of column experiments designed to measure the retardation, in different geological media, of four common ground water VOCs (chloroform, carbon tetrachloride, trichloroethylene, and tetrachloroethylene) which have differing physical and chemical characteristics. It also included a series of diffusion parameters that constrain the model, we compared the data from these experiments to the output of a computational model.

  2. Method for detecting toxic gases

    DOEpatents

    Stetter, Joseph R. (Naperville, IL); Zaromb, Solomon (Hinsdale, IL); Findlay, Jr., Melvin W. (Bolingbrook, IL)

    1991-01-01

    A method capable of detecting low concentrations of a pollutant or other component in air or other gas, utilizing a combination of a heating filament having a catalytic surface of a noble metal for exposure to the gas and producing a derivative chemical product from the component, and an electrochemical sensor responsive to the derivative chemical product for providing a signal indicative of the product. At concentrations in the order of about 1-100 ppm of tetrachloroethylene, neither the heating filament nor the electrochemical sensor is individually capable of sensing the pollutant. In the combination, the heating filament converts the benzyl chloride to one or more derivative chemical products which may be detected by the electrochemical sensor.

  3. Removal characteristics of trace compounds of landfill gas by activated carbon adsorption.

    PubMed

    Shin, Ho-Chul; Park, Jin-Won; Park, Kwinam; Song, Ho-Cheol

    2002-01-01

    The removal characteristics of trace compounds and moisture in raw landfill gas (LFG) were studied. The LFG from the extraction well was saturated with water and moisture was eliminated by physical methods including cyclone-type dehydrator and compressor. The moisture removal efficiency of dehydrator and compressor was above 80%. As the moisture contents of LFG decreased, the toxic compounds like aromatics and chlorinated compounds were effectively removed by using the granular activated carbon. The breakthrough time and adsorption capacity of benzene, toluene, and ethyl benzene decreased rapidly when the relative humidity is over 60%. The effect of moisture was more pronounced at lower adsorbate concentrations tested than at higher concentrations. The breakthrough curves for multi-component mixtures show displacement effects. In the course of competing adsorption, adsorbates with strong interaction force to displace weakly bounded substances. Adsorption by activated carbon is in descending order of xylene, ethylbenzene, toluene, tri or tetrachloroethylene, benzene, carbon tetrachloride and chloroform in LFG, respectively. PMID:12152829

  4. Metabolism of halogenated ethylenes.

    PubMed Central

    Leibman, K C; Ortiz, E

    1977-01-01

    The metabolism of the chlorinated ethylenes may be explained by the formation of chloroethylene epoxides as the first intermediate products. The evidence indicates that these epoxides rearrange with migration of chlorine to form chloroacetaldehydes and chloroacetyl chlorides. Thus, monochloroacetic acid, chloral hydrate, and trichloroacetic acid have been found in reaction mixtures of 1,1-dichloroethylene, trichloroethylene, and tetrachloroethylene, respectively, with rat liver microsomal systems. Rearrangements of the chloroethylene, and glycols formed from the epoxides by hydration may also take place, but would appear, at least in the case of 1,1-dichloroethylene, to be quantitatively less important. The literature on the metabolism of chlorinated ethylenes and its relationship to their toxicity is reviewed. PMID:612463

  5. Operations Support of Phase 2 Integrated Demonstration In Situ Bioremediation. Volume 1, Final report: Final report text data in tabular form, Disk 1

    SciTech Connect

    Hazen, T.C. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1993-09-01

    This project was designed to demonstrate in situ bioremediation of ground water and sediment contaminated with chlorinated solvents. Indigenous microorganisms were stimulated to degrade trichlorethylene (TCE), tetrachloroethylene (PCE) and their daughter products in situ by addition of nutrients to the contaminated aquifer and adjacent vadose zone. The principle carbon/energy source nutrient used in this demonstration was methane (natural gas). In situ biodegradation is a highly attractive technology for remediation because contaminants are destroyed, not simply moved to another location or immobilized, thus decreasing costs, risks, and time, while increasing efficiency, safety, and public and regulatory acceptability. This report describes the preliminary results of the demonstration and provides conclusions only for those measures that the Bioremediation Technical Support Group felt were so overwhelmingly convincing that they do not require further analyses. Though this report is necessarily superficial it does intend to provide a basis for further evaluating the technology and for practitioners to immediately apply some parts of the technology.

  6. Competitive Sorption and Desorption of Chlorinated Organic Solvents (DNAPLs) in Engineered Natural Organic Matter

    SciTech Connect

    Tang, Jixin; Weber, Walter J., Jr.

    2004-03-31

    The effects of artificially accelerated geochemical condensation and maturation of natural organic matter on the sorption and desorption of trichloroethylene (TCE) and tetrachloroethylene (PCE) were studied. The sorption and desorption of TCE in the presence and absence of the competing PCE and 1,2-dichlorobenzene (DCB) were also examined. A sphagnum peat comprising geologically young organic matter was artificially ''aged'' using superheated water, thus increasing the aromaticity and the degree of condensation of its associated organic matter. The sorption of all solutes tested were increased remarkably and their respective desorptions reduced, by the aged peat. The sorption capacities and isotherm nonlinearities of the peat for both TCE and PCE were found to increase as treatment temperature increased. In the competitive sorption studies, both PCE and DCB were found to depress TCE sorption, with PCE having greater effects than DCB, presumably because the molecular structure o f the former is more similar to that of TCE.

  7. Risk assessment of seeps from the 317 Area of Argonne National Laboratory

    SciTech Connect

    NONE

    1996-09-17

    Chlorinated hydrocarbon contaminants have recently been detected in groundwater seeps on forest preserve property south of the 317 Area at ANL. The 317 Area is near ANL`s southern boundary and is considered the source of the contamination. Five seeps are about 200 m south of the ANL property line and about same distance from the nearest developed trails in the forest preserve. Conservative assumptions were used to assess the possibility of adverse health effects associated with forest preserve seeps impacted by the 317 Area. Results indicate that neither cancer risks nor noncarcinogenic effects associated with exposures to seep contaminants are a concern; thus, the area is safe for all visitors. The ecological impact study found that the presence of the three contaminants (CCl{sub 4}, CHCl{sub 3}, tetrachloroethylene) in the seep water does not pose a risk to biota in the area.

  8. Metallurgical Laboratory Hazardous Waste Management Facility groundwater monitoring report. First quarter 1993

    SciTech Connect

    Not Available

    1993-06-01

    During first quarter 1993, samples from 18 groundwater monitoring wells of the AMB series at the Metallurgical Laboratory Hazardous Waste Management Facility were analyzed for certain heavy metals, indicator parameters, radionuclides, volatile organic compounds, and other constituents. Nine parameters exceeded standards during the quarter. As in fourth quarter 1992, tetrachloroethylene and trichloroethylene exceeded the final Primary Drinking Water Standards in 4 and 7 wells, respectively. Dichloromethane (methylene chloride), not previously compared to a standard in the Savannah River Site Groundwater Monitoring Program, was elevated in one well. Aluminum, iron, manganese, pH, specific conductance, and total organic halogens exceeded the Savannah River Site Flag 2 criteria; all of these parameters, with the exception of aluminum, were reported as elevated in AMB wells during previous quarters. Groundwater flow directions and rates in the water-table unit and the upper section of the Congaree were similar to previous quarters.

  9. Mixed Waste Management Facility (MWMF) groundwater monitoring report: Third quarter 1993

    SciTech Connect

    Not Available

    1993-12-01

    During third quarter 1993, eight constituents exceeded final Primary Drinking Water Standards in groundwater samples from downgradient monitoring wells at the Mixed Waste Management Facility, the Old Burial Ground, the E-Area Vaults, and the proposed Hazardous Waste/Mixed Waste Disposal Vaults. As in previous quarters, tritium and trichloroethylene were the most widespread constituents Chloroethene (vinyl chloride), 1,1-dichloroethylene, dichloromethane (methylene chloride), lead, mercury, or tetrachloroethylene also exceeded standards in one or more wells. The elevated constituents were found in Aquifer Zone IIB{sub 2} (Water Table) and Aquifer Zone IIB{sub 1} (Barnwell/McBean) wells. No elevated constituents were exhibited in Aquifer Unit IIA (Congaree) wells. The groundwater flow directions and rates in the three hydrostratigraphic units were similar to those of previous quarters.

  10. Health assessment for Aberdeen Proving Grounds, Aberdeen, Maryland, Region 3. CERCLIS Nos. MD3210021355 and MD10020036. Preliminary report

    SciTech Connect

    Not Available

    1989-01-19

    The Aberdeen Proving Grounds site is located in Aberdeen (Harford County) Maryland. Preliminary on-site groundwater and surface water sampling results have identified various metals, phosphorus, and volatile organic compounds. They include: 1,2-dichloroethylene, chloroform, 1,2-dichloroethane, trichloroethylene, benzene, 1,1,2,2-tetrachloroethane, tetrachloroethylene, 1,4-dithiane and 1,2-dichloroethylene. In addition, it has been reported that among the substances disposed of on-site are significant quantities of toxic metals, cyanide compounds, phosphorus, phosgene, napalm, and mustard gas. The site is considered to be of public health concern because of the risk to human health caused by the likelihood of human exposure to hazardous substances. Potential environmental pathways include those related to contaminated groundwater, surface water, on-site soils, and volatilization of contaminants in ambient air.

  11. Bioremediation of contaminated groundwater

    DOEpatents

    Hazen, T.C.; Fliermans, C.B.

    1994-01-01

    Disclosed is an apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid (NF) is selected to simulated the growth and reproduction of indigenous subsurface microorganisms capable of degrading the contaminants; an oxygenated fluid (OF) is selected to create an aerobic environment with anaerobic pockets. NF is injected periodically while OF is injected continuously and both are extracted so that both are drawn across the plume. NF stimulates microbial colony growth; withholding it periodically forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is acceptable. NF can be methane and OF be air, for stimulating production of methanotrophs to break down chlorohydrocarbons, especially TCE and tetrachloroethylene.

  12. Distribution of natural halocarbons in marine boundary air over the Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Yokouchi, Yoko; Inoue, Jun; Toom-Sauntry, Desiree

    2013-08-01

    Ongoing environmental changes in the Arctic will affect the exchange of natural volatile organic compounds between the atmosphere and the Arctic Ocean. Among these compounds, natural halocarbons play an important role in atmospheric ozone chemistry. We measured the distribution of five major natural halocarbons (methyl iodide, bromoform, dibromomethane, methyl chloride, and methyl bromide) together with dimethyl sulfide and tetrachloroethylene in the atmosphere over the Arctic Ocean (from the Bering Strait to 79°N) and along the cruise path to and from Japan. Methyl iodide, bromoform, and dibromomethane were most abundant near perennial sea ice in air masses derived from coastal regions and least abundant in the northernmost Arctic, where the air masses had passed over the ice pack, whereas methyl chloride and methyl bromide showed the opposite distribution pattern. Factors controlling those distributions and future prospects for natural halocarbons in the Arctic are discussed.

  13. Geohydrology and the occurrence of volatile organic compounds in ground water, Culpeper basin of Prince William County, Virginia

    SciTech Connect

    Nelms, D.L.; Richardson, D.L. (Geological Survey, Richmond, VA (United States))

    1990-01-01

    The Culpeper basin of Prince William County comprises an interbedded sequence of Upper Triassic and Lower Jurassic sedimentary and volcanic rocks. This sequence is intersected by diabase intrusives and thermally metamorphosed rocks. The rocks of the Culpeper basin are highly fractured and overlain by a thin cover of overburden. Groundwater in the Culpeper basin flows generally from the uplands along lineaments to the lowlands or valleys. Pumping from municipal-supply wells has caused two cones of depression in the Manassas-Manassas Park area. Volatile organic compounds have been detected in groundwater in 5 areas of the Culpeper basin in the county. The dominant volatile organic compounds detected are tetrachloroethylene, trichloroethylene, and 1,1,1-trichloroethane. Concentrations of the volatile organic compounds range from 0.1 to 5,300 microg/L. 62 refs., 20 figs., 15 tabs.

  14. Mixed Waste Management Facility (MWMF) groundwater monitoring report

    SciTech Connect

    Thompson, C.Y.

    1992-06-01

    During first quarter 1992, tritium, trichloroethylene, tetrachloroethylene, lead, antimony, I,I-dichloroethylene, 1,2-dichloroethane, gross alpha, mercury, nickel, nitrate, nonvolatile beta, and total alpha-emitting radium (radium-224 and radium-226) exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the Mixed Waste Management Facility (MWMF) and adjacent facilities. Tritium and trichloroethylene were the most widespread constituents; 57 (49%) of the 116 monitored wells contained elevated tritium activities, and 21 (18%) wells exhibited elevated trichloroethylene concentrations Sixty-one downgradient wells screened in Aquifer Zone IIB2 (Water Table), Aquifer Zone IIB[sub 2] (Barnwell/McBean), and Aquifer Unit IIA (Congaree) contained constituents that exceeded the PDWS during first quarter 1992. Upgradient wells BGO 1D and HSB 85A, BC, and 85C did not contain any constituents that exceeded the PDWS. Upgradient well BGO 2D contained elevated tritium.

  15. Sanitary landfill groundwater monitoring report. Fourth quarter 1994 and 1994 summary

    SciTech Connect

    NONE

    1995-02-01

    Eighty-nine wells of the LFW series monitor groundwater quality in the Steed Pond Aquifer (Water Table) beneath the Sanitary Landfill at the Savannah River Site (SRS). These wells are sampled quarterly to comply with the South Carolina Department of Health and Environmental Control Domestic Waste Permit DWP-087A and as part of the SRS Groundwater Monitoring Program. Dichloromethane, a common laboratory contaminant, and trichloroethylene were the most widespread constituents exceeding standards during 1994. Benzene, chloroethene (vinyl chloride), 1,2-dichloroethane, 1,1-dichloroethylene, 1,2-dichloropropane, gross alpha, mercury, nonvolatile beta, tetrachloroethylene, and tritium also exceeded standards in one or more wells. The groundwater flow direction in the Steed Pond Aquifer (Water Table) beneath the Sanitary Landfill was to the southeast (universal transverse Mercator coordinates). The flow rate in this unit was approximately 140 ft/year during first and fourth quarters 1994.

  16. Mixed Waste Management Facility (MWMF) groundwater monitoring report. First quarter 1992

    SciTech Connect

    Thompson, C.Y.

    1992-06-01

    During first quarter 1992, tritium, trichloroethylene, tetrachloroethylene, lead, antimony, I,I-dichloroethylene, 1,2-dichloroethane, gross alpha, mercury, nickel, nitrate, nonvolatile beta, and total alpha-emitting radium (radium-224 and radium-226) exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in groundwater samples from monitoring wells at the Mixed Waste Management Facility (MWMF) and adjacent facilities. Tritium and trichloroethylene were the most widespread constituents; 57 (49%) of the 116 monitored wells contained elevated tritium activities, and 21 (18%) wells exhibited elevated trichloroethylene concentrations Sixty-one downgradient wells screened in Aquifer Zone IIB2 (Water Table), Aquifer Zone IIB{sub 2} (Barnwell/McBean), and Aquifer Unit IIA (Congaree) contained constituents that exceeded the PDWS during first quarter 1992. Upgradient wells BGO 1D and HSB 85A, BC, and 85C did not contain any constituents that exceeded the PDWS. Upgradient well BGO 2D contained elevated tritium.

  17. Bioremediation of contaminated groundwater

    DOEpatents

    Hazen, Terry C. (Augusta, GA); Fliermans, Carl B. (Augusta, GA)

    1995-01-01

    An apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid is selected to stimulate the growth and reproduction of indigenous subsurface microorganisms that are capable of degrading the contaminants; an oxygenated fluid is selected to create a generally aerobic environment for these microorganisms to degrade the contaminants, leaving only pockets that are anaerobic. The nutrient fluid is injected periodically while the oxygenated fluid is injected continuously and both are extracted so that both are drawn across the plume. The nutrient fluid stimulates microbial colony growth; withholding it periodicially forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is reduced to an acceptable, preselected level. The nutrient fluid can be methane and the oxygenated fluid air for stimulating production of methanotrophs to break down chlorohydrocarbons, especially trichloroethylene (TCE) and tetrachloroethylene.

  18. Mixed Waste Management Facility (MWMF) groundwater monitoring report. First quarter 1993

    SciTech Connect

    Not Available

    1993-06-01

    During first quarter 1993, eight constituents exceeded final Primary Drinking Water Standards in groundwater samples from downgradient monitoring wells at the Mixed Waste anagement Facility, the Old Burial Ground, the E-Area Vaults, and the proposed Hazardous Waste/Mixed Waste Disposal Vaults (HWMWDV). As in previous quarters, tritium and trichloroethylene were the most widespread constituents. Tetrachloroethylene, chloroethene, 1,1-dichloroethylene, gross alpha, lead, or nonvolatile beta levels also exceeded standards in one or more wells. The elevated constituents were found primarily in Aquifer Zone IIB{sub 2} (Water Table) and Aquifer Zone IIB{sub 1}, (Barnwell/McBean) wells. However, several Aquifer Unit IIA (Congaree) wells also contained elevated constituent levels. The groundwater flow directions and rates in the three hydrostratigraphic units were similar to previous quarters.

  19. Mixed Waste Management Facility (MWMF) groundwater monitoring report. Third quarter 1992

    SciTech Connect

    Thompson, C.Y.

    1992-12-01

    During third quarter 1992, 12 constituents exceeded the US Environmental Protection Agency Primary Drinking Water Standards (PDWS) in one or more groundwater samples from monitoring wells at the Mixed Waste Management Facility and adjacent facilities. Tritium and trichloroethylene were the most widespread constituents: 57 (48%) and 23 (19%) of the 119 monitoring wells contained elevated tritium and trichloroethylene levels, respectively. Elevated constituents were found primarily in Aquifer Zone IIB{sub 2} (Water Table) and Aquifer Zone IIB{sub 1} (Barnwell/McBean). Elevated constituents also occurred in five Aquifer Unit IIA (Congaree) wells. Upgradient wells BGO 1D and 2D and HSB 85A, 85B, and 85C did not contain any constituents that exceeded the PDWS. Downgradient wells in the three hydrostratigraphic units contained elevated levels of tritium, trichloroethylene, tetrachloroethylene, chloroethene, antimony, 1,1-dichloroethylene, gross alpha, lead, nonvolatile beta, thallium, total alpha-emitting radium (radium-224 and radium-226), or cadmium.

  20. Health assessment for Vega Alta Public Supply Wells Site, Vega Alta, Puerto Rico, Region 2. CERCLIS No. PRS187147. Final report

    SciTech Connect

    Not Available

    1988-12-02

    The Vega Alta Public Supply Wells Site is a public water supply wellfield located in the municipality of Vega Alta, Puerto Rico. Based on data collected from 1983 to 1985, the ground water is contaminated with volatile organic chemicals (VOCs), notably trichloroethylene, tetrachloroethylene, and 1,2-trans-dichloroethylene. A remediation alternative selected in a Record of Decision dated September 29, 1987 calls for treatment of 4 of the more highly contaminated wells and shutting down 2 others. Remediation efforts are to include air stripping and possibly treatment by carbon adsorption. Monitoring of the effectiveness of these efforts will determined their adequacy to bring the quality of the tap water to acceptable levels. It is not known whether the water currently supplied through the municipality has elevated concentrations of VOCs. Therefore, based on the limited information available, ATSDR has concluded that the Vega Alta Wells site is of public health concern.

  1. Health assessment for Aerojet-General Corporation, Rancho Cordova, Sac Ramento County, California, Region 9. CERCLIS No. CAD980358832. Preliminary report

    SciTech Connect

    Not Available

    1988-12-05

    The Aerojet-General Corporation site is on the National Priorities List. Since the 1950s, Aerojet-General has manufactured liquid and solid propellent rocket engines for military and commercial applications, and has formulated a number of chemicals. The environmental contamination on-site (maximum concentrations reported) consists of trichloroethylene (12 ppm), toluene (4.2 ppm), chloroform (100 ppm), and methylene chloride (5.9 ppm) in ground water; and 1,1-dichloroethane (1.6 ppm), 1,1,1-trichloroethane (1.8 ppm), carbon tetrachloride (1 ppm), and tetrachloroethylene (0.6 ppm) in surface water. The site is considered to be of potential public health concern because of the risk to human health caused by the likelihood of exposure to hazardous substances via contaminated ground water.

  2. Different behavioral effect dose-response profiles in mice exposed to two-carbon chlorinated hydrocarbons: influence of structural and physical properties.

    PubMed

    Umezu, Toyoshi; Shibata, Yasuyuki

    2014-09-01

    The present study aimed to clarify whether dose-response profiles of acute behavioral effects of 1,2-dichloroethane (DCE), 1,1,1-trichloroethane (TCE), trichloroethylene (TRIC), and tetrachloroethylene (PERC) differ. A test battery involving 6 behavioral endpoints was applied to evaluate the effects of DCE, TCE, TRIC, and PERC in male ICR strain mice under the same experimental conditions. The behavioral effect dose-response profiles of these compounds differed. Regression analysis was used to evaluate the relationship between the dose-response profiles and structural and physical properties of the compounds. Dose-response profile differences correlated significantly with differences in specific structural and physical properties. These results suggest that differences in specific structural and physical properties of DCE, TCE, TRIC, and PERC are responsible for differences in behavioral effects that lead to a variety of dose-response profiles. PMID:24910396

  3. TNX-Area groundwater monitoring report. 1993 Annual report

    SciTech Connect

    Not Available

    1994-05-01

    During 1993, samples from well cluster P 26 and the TBG, TNX, XSB, and YSB well series at the TNX Area were analyzed for selected heavy metals, indicator parameters, radionuclides, volatile organic compounds, and other constituents. Seven parameters exceeded the final Primary Drinking Water Standards (PDWS). Dichloromethane (methylene chloride), a common laboratory contaminant, nitrate, and trichloroethylene exceeded PDWS most frequently. Four wells in this area currently are part of the Purge Water Contaminant Program due to high trichloroethylene concentrations. Carbon tetrachloride, gross alpha, lead, and tetrachloroethylene were elevated sporadically in one or more wells during the year. Groundwater flow directions and rates in the Unconfined Aquifer were similar from quarter to quarter during the year.

  4. Air pollutants formed in thermal decomposition of folpet fungicide under oxidative conditions.

    PubMed

    Chen, Kai; Mackie, John C; Kennedy, Eric M; Dlugogorski, Bogdan Z

    2011-01-15

    This contribution studies the decomposition of folpet fungicide under oxidative conditions and compares the product species with those of captan fungicide, which is structurally related to folpet. Toxic products arising from folpet comprised carbon disulfide (highest emission factor of 4.9 mg g(-1) folpet), thiophosgene (14.4), phosgene (34.1), hydrogen cyanide (2.6), tetrachloroethylene (111), hexachloroethane (167), and benzonitrile (4.5). Owing to their related molecular structures, folpet emitted similar products to captan but at different yields, under the same experimental conditions. It appears that the availability of easily abstractable H atoms, in the structure of captan but not in that of folpet, defines the product distribution. In conjunction with the quantum chemical calculations, these experimental measurements afford an enhanced explanation of the formation pathways of hazardous decomposition products of these two structurally related fungicides. PMID:21121660

  5. P-Area Reactor 1993 annual groundwater monitoring report

    SciTech Connect

    NONE

    1994-11-01

    Groundwater was sampled and analyzed during 1993 from wells monitoring the water table at the following locations in P Area: well P 24A in the eastern section of P Area, the P-Area Acid/Caustic Basin, the P-Area Coal Pile Runoff Containment Basin, the P-Area Disassembly Basin, the P-Area Burning/Rubble Pit, and the P-Area Seepage Basins. During 1993, pH was above its alkaline standard in well P 24A. Specific conductance was above its standard in one well each from the PAC and PCB series. Lead exceeded its 50 {mu}g/L standard in one well of the PDB series during one quarter. Tetrachloroethylene and trichloroethylene were detected above their final primary drinking water standards in one well of the PRP well series. Tritium was consistently above its DWS in the PDB and PSB series. Also during 1993, radium-228 exceeded the DWS for total radium in three wells of the PAC series and one well of the PCB series; total alpha-emitting radium exceeded the same standard in a different PCB well. These results are fairly consistent with those from previous years. Unlike results from past years, however, no halogenated volatiles other than trichloroethylene and tetrachloroethylene exceeded DWS in the PRP well series although gas chromatographic volatile organic analyses were performed throughout the year. Some of the regulated units in P Area appear to need additional monitoring by new wells because there are insufficient downgradient wells, sometimes because the original well network, installed prior to regulation, included sidegradient rather than downgradient wells. No monitoring wells had been installed through 1993 at one of the RCRA/CERCLA units named in the Federal Facilities Agreement, the Bingham Pump Outage Pits.

  6. Volatile organic compounds detected in vapor-diffusion samplers placed in sediments along and near the shoreline at Allen Harbor Landfill and Calf Pasture Point, Davisville, Rhode Island, March-April 1998

    USGS Publications Warehouse

    Lyford, F.P.; Kliever, J.D.; Scott, Clifford

    1999-01-01

    Volatile organic compounds are present in ground water at the Allen Harbor Landfill and the Calf Pasture Point sites on the former Naval Construction Battalion Center in Davisville, R.I. Vapor-diffusion samplers were used at the two sites during March-April 1998 to identify possible discharge points for contaminants along the shore of Allen Harbor and in two wetland areas near the shore. Results from vapor-diffusion samplers will be used in conjunction with other site information to evaluate proposed ground-water monitoring programs. Volatile organic compounds were detected in 41 of 115 samplers placed along the shoreline at the Allen Harbor Landfill. Trichloroethylene was the principal volatile organic compound detected of eight target compounds. The highest vapor concentration measured exceeded 300,000 parts per billion by volume in an area where TCE was detected in groundwater from nearby monitoring wells. Other chemicals detected in vapor-diffusion samplers included tetrachloroethylene, toluene, and benzene. Concentrations of individual volatile organic compounds were less than 100 parts per billion by volume in most samplers. Volatile organic compounds, principally trichloroethylene, were detected in 7 of 30 samplers placed along the shoreline at Calf Pasture Point; the highest trichloroethylene concentration was 1,900 parts per billion by volume. A trace concentration of tetrachloroethylene was detected in one of the samplers. One of 24 samplers placed in two wetland areas near the shore (suspected discharge areas for ground-water containing volatile organic compounds) detected trichloroethylene at a vapor concentration of 14 parts per billion by volume.

  7. Ground-water contamination in East Bay Township, Michigan

    USGS Publications Warehouse

    Twenter, F.R.; Cummings, T.R.; Grannemann, N.G.

    1985-01-01

    Glacial deposits, as much as 360 feet thick, underlie the study area. The upper 29 to 118 feet, a sand and gravel unit, is the aquifer tapped by all wells in the area. This unit is underlain by impermeable clay that is at least 100 feet thick. Ground-water flow is northeastward at an estimated rate of 2 to 5 feet per day. Hydraulic conductivities in the aquifer range from 85 to 250 feet per day; 120 feet per day provided the best match of field data in a ground-water flow model. The depth to water ranged from 1 to 20 feet. Chemical analyses indicate that ground water is contaminated with organic chemicals from near the Hangar/Administration building at the U.S. Coast Guard Air Station at East Bay, about 4,300 feet northeast. The plume, which follows ground-water flow lines, ranges from 180 to 400 feet wide. In the upper reach of the plume, hydrocarbons less dense than water occur at the surface of the water table; they move downward in the aquifer as they move toward east Bay. Maximum concentrations of the major organic compounds include: benzene, 3,390 ug/L; toluene, 55,500 ug/L; xylene, 3,900 ug/L, tetrachloroethylene, 3,410 ug/L; amd bis (2-ethyl hexyl) phthalate, 2,100 ug/L. Soils are generally free of these hydrocarbons; however, in the vicinity of past drum storage, aircraft maintenance operations, and fuel storage and dispensing , as much as 1,100 ug/kg of tetrachloroethylene and 1,500 ug/kg of bis (-ethyl hexyl) phthalate were detected. At a few locations higher molecular weight hydrocarbons, characteristic of petroleum distillates were found. (USGS)

  8. Historical review on development of environmental quality standards and guideline values for air pollutants in Japan.

    PubMed

    Kawamoto, Toshihiro; Pham, Thi-Thu-Phuong; Matsuda, Takayuki; Oyama, Tsunehiro; Tanaka, Masayuki; Yu, Hsu-Sheng; Uchiyama, Iwao

    2011-07-01

    Environmental quality standards (EQSs) have been established as desirable levels to be maintained for protection of human health and the conservation of the living environment by Basic Environment Law. EQSs in ambient air had been set for 10 substances (sulfur dioxide (SO(2)), carbon monoxide (CO), suspended particulate matter (SPM), nitrogen dioxide (NO(2)) and photochemical oxidants (Ox), benzene, tetrachloroethylene, trichloroethylene, dioxins and dichloromethane) and guideline values for 7 (acrylonitorile, vinyl chloride monomer, mercury, nickel compounds, 1,3-butadiene, chloroform and 1,2-dichloromethane) in Japan by 2009. EQSs for the classical (or traditional) air pollutants, SO(2), CO, SPM, NO(2) and Ox, were set according to the minimal requirement to protect human health, based on evidence from epidemiological studies conducted before the 1970s. In 1996, the Central Environment Council designated substances which may be hazardous air pollutants and substances requiring priority action, and adopted the concept of risk assessment to set EQSs and guideline values. A life-long risk level (virtually safe dose) of 10(-5) was used to set EQS for benzene, and guideline values for vinyl chloride monomer, nickel compounds, and 1,3-butadiene. EQSs for trichloroethylene, tetrachloroethylene and dichloromethane, and guideline values for acrylonitorile and mercury were set using uncertain factors and lowest observed adverse effect (LOAEL)/no observed adverse effect level (NOAEL). The results of animal experiments were utilized to set guideline values for chloroform and 1,2-dichloroethane. The benchmark approach and human equivalent concentration (HEC) were adopted for 1,2-dichloroethane. The history of setting EQSs and guideline values for hazardous air pollutants is one of adopting new concepts into risk assessment. PMID:21680244

  9. High-Intensity Transmission Properties Of Conventional And Polymeric Index-Matching Fluids

    NASA Astrophysics Data System (ADS)

    Smith, W. L.

    1981-12-01

    Large-aperture harmonic generation is rapidly becoming a standard practice in laser-fusion research. At present, harmonic generation is commonly done with bare nonlinear crystals--that is, crystal plates not protected from atmospheric degradation, and not relieved of Fresnel loss, by anti-reflection windows and index-matching fluid. This situation has been dictated by the recently-observed, aperture-dependent nonlinear loss in harmonic generation cells using layers of conventional index-matching fluids (Cargille 5610 and FC104). While the overall cost of using bare crystals can be tolerated at the small apertures (10-15 cm) in use at present, for the 74-cm harmonic crystal arrays to be used on the Nova laser, loss-free and degradation-free performance is required. In this paper, results will be presented from a study of the 0.53-pm and 1.06-pm high-intensity transmission properties of 10 organic fluids: benzonitrile, benzene, xylene, tetrachloroethylene, acetonitrile, decahydronaphtalene, Cargille 5610, FC104, poly-chlorotrifluoroethylene (Halocarbon 56) and poly-bromotrifluoroethylene (BFC57). We present measurements of the threshold for stimulated Raman scattering (SRS) in 8 of the fluids in a standardized 8-cm, longitudinal geometry. In the two polymeric fluids, SRS was not detected at input intensities up to the superbroadening thresholds (43 and 62 GW/cm2, respectively). Suppression of SRS in these two fluids is achieved by fluorination and polymerization of the parent tetrachloroethylene molecule. Results will also be related from tests in the required transverse geometry, using 8-cm aperture, 0.532-pm pulses of up to 3 GW/cm2. The aforementioned loss mechanism in Cargille 5610 is identified to be transverse stimulated Raman scattering. Finally, we describe a successful demonstration of loss-free, damage-free performance at an aperture-intensity product of 25 GW/cm in Halocarbon 56 fluid.

  10. Evaluation of the atmosphere as a source of volatile organic compounds in shallow groundwater

    USGS Publications Warehouse

    Baehr, A.L.; Stackelberg, P.E.

    1999-01-01

    The atmosphere as a source of volatile organic compounds (VOCs) in shallow groundwater was evaluated over an area in southern New Jersey. Chloroform, methyl tertbutyl ether (MTBE), 1,1,1-trichloroethane, tetrachloroethylene (PCE), and carbon disulfide (not a VOC) were detected frequently at low-level concentrations in a network of 78 shallow wells in the surficial Kirkwood-Cohansey aquifer system. The atmosphere was sampled for these compounds and only MTBE concentrations were high enough to potentially explain frequent detection in shallow groundwater. A mathematical model of reactive transport through the unsaturated zone is presented to explain how variations in unsaturated properties across the study area could explain differences in MTBE concentrations in shallow groundwater given the atmosphere as the source. Even when concentrations of VOCs in groundwater are low compared to regulatory concentration limits, it is critical to know the source. If the VOCs originate from a point source(s), concentrations in groundwater could potentially increase over time to levels of concern as groundwater plumes evolve, whereas if the atmosphere is the source, then groundwater concentrations would be expected to remain at low-level concentrations not exceeding those in equilibrium with atmospheric concentrations. This is the first analysis of VOC occurrence in shallow groundwater involving colocated atmosphere data.The atmosphere as a source of volatile organic compounds (VOCs) in shallow groundwater was evaluated over an area in southern New Jersey. Chloroform, methyl tert-butyl ether (MTBE), 1,1,1-trichloroethane, tetrachloroethylene (PCE), and carbon disulfide (not a VOC) were detected frequently at low-level concentrations in a network of 78 shallow wells in the surficial Kirkwood-Cohansey aquifer system. The atmosphere was sampled for these compounds and only MTBE concentrations were high enough to potentially explain frequent detection in shallow groundwater. A mathematical model of reactive transport through the unsaturated zone is presented to explain how variations in unsaturated properties across the study area could explain differences in MTBE concentrations in shallow groundwater given the atmosphere as the source. Even when concentrations of VOCs in groundwater are low compared to regulatory concentration limits, it is critical to know the source. If the VOCs originate from a point source(s), concentrations in groundwater could potentially increase over time to levels of concern as groundwater plumes evolve, whereas if the atmosphere is the source, then groundwater concentrations would be expected to remain at low-level concentrations not exceeding those in equilibrium with atmospheric concentrations. This is the first analysis of VOC occurrence in shallow groundwater involving collocated atmosphere data.

  11. Test plan for Geo-Cleanse{reg_sign} demonstration (in situ destruction of dense non-aqueous phase liquid (DNAPL))

    SciTech Connect

    Jerome, K.M.; Looney, B.B.; Accorsi, F.; Dingens, M.; Wilson, J.T.

    1996-09-01

    Soils and groundwater beneath an abandoned process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLs, or dense non-aqueous phase liquids. Technologies targeted at the efficient characterization or removal of DNAPL are not currently proven. For example, most DNAPL studies rely on traditional soil and water sampling and the fortuitous observation of immiscible solvent. Once DNAPL is identified, soil excavation (which is only applicable to small contained spill sites) is the only proven cleanup method. New cleanup approaches based on destruction of DNAPL either in situ or ex situ have been proposed and tested at the pilot scale. The proposed demonstration, as described in this report will evaluate the applicability to DNAPL plumes of a technology proven for in situ destruction of light non-aqueous phase liquids (LNAPLs) such as oils.

  12. Health assessment for Welsh Road/Barkman Landfill, Honey Brook, Chester County, Pennsylvania, Region 3. CERCLIS No. PAD980829527. Preliminary report

    SciTech Connect

    Not Available

    1988-12-02

    The Welsh Road/Barkman Landfill site in Honey Brook, Pennsylvania was an unpermitted residential and commercial refuse disposal facility that operated from 1963 to sometime in the 1980s. After 1977, the landfill continued to operate in defiance of legal action to support a closure plan. Various investigations conducted in the 1980s revealed that industrial and hazardous waste had been accepted by the site. The environmental contamination on-site consists of copper, lead, 1,2-dichloropropane, toluene, chloroform and methylene chloride in drummed wastes; and mercury, toluene, dichlorofluoromethane, methylene chloride, trichlorofluoromethane, 5-methyl-2-hexanone, trichloroethylene, 1,2-dichloroethane, and 1,3,5-cycloheptatriene in groundwater. One time sampling indicated the presence of volatile compounds in air (hydrogen chloride and chloroform). The environmental contamination off-site consists of cadmium in sediment; and chloromethane, chloroform, xylenes, dichlorofluoromethane, 1,1-dichloroethane, tetrachloroethylene, p-cresol, toluene, methyl isobutyl ketone, di-n-butyl phthalate, lead, mercury, and zinc in residential well water. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via contaminated groundwater, surface water, soil, sediment, and airborne gases, vapors, and particulate.

  13. Involvement of a collar structure in polar growth and cell division of strain DCB-1

    SciTech Connect

    Mohn, W.W.; Linkfield, T.G.; Pankratz, H.S.; Tiedje, J.M. (Michigan State Univ., East Lansing (USA))

    1990-05-01

    Strain DCB-1 was isolated from an anaerobic enrichment culture which mineralized 3-chlorobenzoate. Apparently, this isolate is a unique type of sulfate-reducing bacterium. The isolate is capable of reductive dehalogenation of 3-chlorobenzoate, other halogenated benzoates, and tetrachloroethylene and is of special interest since it is the only pure culture capable of anaerobic reductive dehalogenation of aromatic compounds. Dechlorination has recently been shown to provide energy to DCB-1 as a terminal electron-accepting process. Microscopic methods were used to investigate the unique the unique collar structure of the gram-negative sulfate-reducing bacterium, strain DCB-1. Polar cell growth apparently occurred from the collar. When the daughter cell was approximately equal in length to the mother cell and the collar was thus centrally located, cell division occurred within the collar region. Division was by a novel mechanism which conserved the collar of the mother cell and gave rise to a new collar of the daughter cell. Cells of DCB-1 were also found to contain stacked internal membranes and glycogen bodies.

  14. A procedure to design a Permeable Adsorptive Barrier (PAB) for contaminated groundwater remediation.

    PubMed

    Erto, A; Lancia, A; Bortone, I; Di Nardo, A; Di Natale, M; Musmarra, D

    2011-01-01

    A procedure to optimize the design of a Permeable Adsorptive Barrier (PAB) for the remediation of a contaminated aquifer is presented in this paper. A computer code, including different routines that describe the groundwater contaminant transport and the pollutant capture by adsorption in unsteady conditions over the barrier solid surface, has been developed. The complete characterization of the chemical-physical interactions between adsorbing solids and the contaminated water, required by the computer code, has been obtained by experimental measurements. A case study in which the procedure developed has been applied to a tetrachloroethylene (PCE)-contaminated aquifer near a solid waste landfill, in the district of Napoli (Italy), is also presented and the main dimensions of the barrier (length and width) have been evaluated. Model results show that PAB is effective for the remediation of a PCE-contaminated aquifer, since the concentration of PCE flowing out of the barrier is everywhere always lower than the concentration limit provided for in the Italian regulations on groundwater quality. PMID:20846781

  15. Permeable Adsorptive Barrier (PAB) for the remediation of groundwater simultaneously contaminated by some chlorinated organic compounds.

    PubMed

    Erto, A; Bortone, I; Di Nardo, A; Di Natale, M; Musmarra, D

    2014-07-01

    In this paper, a Permeable Reactive Barrier (PRB) made with activated carbon, namely a Permeable Adsorptive Barrier (PAB), is put forward as an effective technique for the remediation of aquifers simultaneously contaminated by some chlorinated organic compounds. A design procedure, based on a computer code and including different routines, is presented as a tool to accurately describe mass transport within the aquifer and adsorption/desorption phenomena occurring inside the barrier. The remediation of a contaminated aquifer near a solid waste landfill in the district of Napoli (Italy), where Tetrachloroethylene (PCE) and Trichloroethylene (TCE) are simultaneously present, is considered as a case study. A complete hydrological and geotechnical site characterization, as well as a number of dedicated adsorption laboratory tests for the determination of activated carbon PCE/TCE adsorption capacity in binary systems, are carried out to support the barrier design. By means of a series of numerical simulations it is possible to determine the optimal barrier location, orientation and dimensions. PABs appear to be an effective remediation tool for the in-situ treatment of an aquifer contaminated by PCE and TCE simultaneously, as the concentration of both compounds flowing out of the barrier is everywhere lower than the regulatory limits on groundwater quality. PMID:24747934

  16. D-area oil seepage basin bioventing optimization test plan

    SciTech Connect

    Berry, C.J.; Radway, J.C.; Alman, D.; Hazen, T.C.

    1998-12-31

    The D Area Oil Seepage Basin (DOSB) was used from 1952 to 1975 for disposal of petroleum-based products (waste oils), general office and cafeteria waste, and apparently some solvents [trichloroethylene (TCE)/tetrachloroethylene (PCE)]. Numerous analytical results have indicated the presence of TCE and its degradation product vinyl chloride in groundwater in and around the unit, and of petroleum hydrocarbons in soils within the unit. The DOSB is slated for additional assessment and perhaps for environmental remediation. In situ bioremediation represents a technology of demonstrated effectiveness in the reclamation of sites contaminated with petroleum hydrocarbons and chlorinated solvents, and has been retained as an alternative for the cleanup of the DOSB. The Savannah River Site is therefore proposing to conduct a field treatability study designed to demonstrate and optimize the effectiveness of in situ microbiological biodegradative processes at the DOSB. The introduction of air and gaseous nutrients via two horizontal injection wells (bioventing) is expected to enhance biodegradation rates of petroleum components and stimulate microbial degradation of chlorinated solvents. The data gathered in this test will allow a determination of the biodegradation rates of contaminants of concern in the soil and groundwater, allow an evaluation of the feasibility of in situ bioremediation of soil and groundwater at the DOSB, and provide data necessary for the functional design criteria for the final remediation system.

  17. Well venting and application of passive soil vapor extraction at Hanford and Savannah River

    SciTech Connect

    Rohay, V.J. [Westinghouse Hanford Co., Richland, WA (United States); Rossabi, J.; Looney, B. [Westinghouse Savannah River Co., Aiken, SC (United States); Cameron, R.; Peters, B. [Ebasco Services, Inc., New York, NY (United States)

    1993-09-01

    At the Hanford and Savannah River Sites, wells with open intervals in the unsaturated zone have been observed to {open_quotes}breathe{close_quotes}, i.e., to inhale ambient air from the surface and to exhale soil gas to the atmosphere. This breathing results primarily from the difference in pressure that develops between the soil pressure near the open interval of a well and the barometric pressure. Volatile organic compounds (VOC) have been identified at both Hanford (carbon tetrachloride) and Savannah River (trichloroethylene and tetrachloroethylene). Passive vapor extraction (PVE) refers to the enhancement and application of this natural breathing phenomenon as a remediation method for increased VOC removal rates from the unsaturated zone. Passive vapor extraction is proposed as a complementary technology to be used with active vapor extraction (AVE). The AVE system would be used to extract soil gas from the high VOC concentration, highly permeable zones. The enhanced PVE would be used to address those zones of lower VOC concentration and those zones where extraction is limited by mass transfer and diffusion. The primary advantages of PVE application are low capital costs and minimal operating costs. This combination allows for many small PVE systems to be placed on individual wells and for the systems to operate for the extended periods of time associated with remediation of sites in which soil-gas transport is diffusion limited.

  18. Removal of contaminants in leachate from landfill by waste steel scrap and converter slag.

    PubMed

    Oh, Byung-Taek; Lee, Jai-Young; Yoon, Jeyong

    2007-08-01

    This study may be the first investigation to be performed into the potential benefits of recycling industrial waste in controlling contaminants in leachate. Batch reactors were used to evaluate the efficacy of waste steel scrap and converter slag to treat mixed contaminants using mimic leachate solution. The waste steel scrap was prepared through pre-treatment by an acid-washed step, which retained both zero-valent iron site and iron oxide site. Extensive trichloroethene (TCE) removal (95%) occurred by acid-washed steel scrap within 48 h. In addition, dehalogenation (Cl(-) production) was observed to be above 7.5% of the added TCE on a molar basis for 48 h. The waste steel scrap also removed tetrachloroethylene (PCE) through the dehalogenation process although to a lesser extent than TCE. Heavy metals (Cr, Mn, Cu, Zn, As, Cd, and Pb) were extensively removed by both acid-washed steel scrap and converter slag through the adsorption process. Among salt ions (NH (4)(+) , NO (3)(-) , and PO (4)(3-) ), PO (4)(3-) was removed by both waste steel scrap (100% within 8 h) and converter slag (100% within 20 min), whereas NO (3)(-) and NH (4)(+ ) were removed by waste steel scrap (100% within 7 days) and converter slag (up to 50% within 4 days) respectively. This work suggests that permeable reactive barriers (PRBs) with waste steel scrap and converter slag might be an effective approach to intercepting mixed contaminants in leachate from landfill. PMID:17492478

  19. Health assessment for Spartan Chemical Company, Wyoming, Michigan, Region 5. CERCLIS No. MID079300125. Preliminary report

    SciTech Connect

    Not Available

    1989-03-01

    The Spartan Chemical Company is listed on the National Priorities List. The company distributes liquid industrial chemicals including lacquer thinners, solvents, and wash thinners. Contamination was detected in 1975. Analyses of sampling revealed the following maximum levels of organic compounds: benzene (1,600 ppb), chlorobenzene (780 ppb), 1,2-dichloroethane (73 ppb), trans-1,2-dichloroethylene (13,000 ppb), 1,2-dichloropropane (140 ppb), tetrachloroethylene (1,100 ppb), toluene (260,000 ppb), 1,1,1-trichloroethane (6,300 ppb), trichloroethylene (1,900 ppb), vinyl chloride (210 ppb), xylene (41,000 ppb), and methyl ethyl ketone (6,200 ppb). Soil borings have shown a similar profile of contaminants. It is notable that, when the contamination was discovered in 1975, explosive conditions prevailed in the storm sewer into which the ground water was discharged. The site is of potential public health concern because of the risk to human health that could result from possible exposure to hazardous substances at levels that may result in adverse health effects over time. Potentially contaminated environmental media are surface and subsurface soil, surface water, ground water, consumable plants and animals, and air.

  20. Sewer Gas: An Indoor Air Source of PCE to Consider During Vapor Intrusion Investigations

    PubMed Central

    Pennell, Kelly G.; Scammell, Madeleine Kangsen; McClean, Michael D.; Ames, Jennifer; Weldon, Brittany; Friguglietti, Leigh; Suuberg, Eric M.; Shen, Rui; Indeglia, Paul A.; Heiger-Bernays, Wendy J.

    2013-01-01

    The United States Environmental Protection Agency (USEPA) is finalizing its vapor intrusion guidelines. One of the important issues related to vapor intrusion is background concentrations of volatile organic chemicals (VOCs) in indoor air, typically attributed to consumer products and building materials. Background concentrations can exist even in the absence of vapor intrusion and are an important consideration when conducting site assessments. In addition, the development of accurate conceptual models that depict pathways for vapor entry into buildings is important during vapor intrusion site assessments. Sewer gas, either as a contributor to background concentrations or as part of the site conceptual model, is not routinely evaluated during vapor intrusion site assessments. The research described herein identifies an instance where vapors emanating directly from a sanitary sewer pipe within a residence were determined to be a source of tetrachloroethylene (PCE) detected in indoor air. Concentrations of PCE in the bathroom range from 2.1 to 190 ug/m3 and exceed typical indoor air concentrations by orders of magnitude resulting in human health risk classified as an “Imminent Hazard” condition. The results suggest that infiltration of sewer gas resulted in PCE concentrations in indoor air that were nearly two-orders of magnitude higher as compared to when infiltration of sewer gas was not known to be occurring. This previously understudied pathway whereby sewers serve as sources of PCE (and potentially other VOC) vapors is highlighted. Implications for vapor intrusion investigations are also discussed. PMID:23950637

  1. Replacement Technologies for Precision Cleaning of Aerospace Hardware for Propellant Service

    NASA Technical Reports Server (NTRS)

    Beeson, Harold; Kirsch, Mike; Hornung, Steven; Biesinger, Paul

    1997-01-01

    The NASA White Sands Test Facility (WSTF) is developing cleaning and verification processes to replace currently used chlorofluorocarbon-l13- (CFC-113-) based processes. The processes being evaluated include both aqueous- and solvent-based techniques. Replacement technologies are being investigated for aerospace hardware and for gauges and instrumentation. This paper includes the findings of investigations of aqueous cleaning and verification of aerospace hardware using known contaminants, such as hydraulic fluid and commonly used oils. The results correlate nonvolatile residue with CFC 113. The studies also include enhancements to aqueous sampling for organic and particulate contamination. Although aqueous alternatives have been identified for several processes, a need still exists for nonaqueous solvent cleaning, such as the cleaning and cleanliness verification of gauges used for oxygen service. The cleaning effectiveness of tetrachloroethylene (PCE), trichloroethylene (TCE), ethanol, hydrochlorofluorocarbon 225 (HCFC 225), HCFC 141b, HFE 7100(R), and Vertrel MCA(R) was evaluated using aerospace gauges and precision instruments and then compared to the cleaning effectiveness of CFC 113. Solvents considered for use in oxygen systems were also tested for oxygen compatibility using high-pressure oxygen autogenous ignition and liquid oxygen mechanical impact testing.

  2. Epidemiology and toxicology of volatile organic chemical contaminants in water absorbed through the skin

    SciTech Connect

    Thomas, R.D. (National Academy of Sciences, Washington, DC (USA))

    1989-10-01

    This paper provides a general introduction to the occurrence, epidemiology, and toxicity of some of the most common contaminants of water supplies, the volatile organic chemicals (VCs). VOCs are formed from the reaction of chlorine during disinfection with naturally occurring carbon in the form of humic acids. The VOCs may also enter water supplies as a result of manufacturing, processing, distribution, and urban and agricultural runoff. Their occurrence is summarized. No epidemiologic studies examine the health effects where skin is the sole route of exposure. However, several studies are reviewed where skin is one of the routes of exposure for VOCs. Finally, the toxicity of some of the more important VOCS is outlined, including chloroform, trichloroethylene, tetrachloroethylene, carbon tetrachloride, benzene, and alkylbenzenes. Where possible, similarities in toxicity between individual members of this class of chemical contaminates are noted. There are striking similarities of toxicity of various VOCs in the liver, kidney, and hematopoietic system. These similarities should be considered as skin exposure models are being developed. 72 refs., 1 fig., 6 tabs.

  3. Air purification from TCE and PCE contamination in a hybrid bioreactors and biofilter integrated system.

    PubMed

    Tabernacka, Agnieszka; Zborowska, Ewa; Lebkowska, Maria; Borawski, Maciej

    2014-01-15

    A two-stage waste air treatment system, consisting of hybrid bioreactors (modified bioscrubbers) and a biofilter, was used to treat waste air containing chlorinated ethenes - trichloroethylene (TCE) and tetrachloroethylene (PCE). The bioreactor was operated with loadings in the range 0.46-5.50gm(-3)h(-1) for TCE and 2.16-9.02gm(-3)h(-1) for PCE. The biofilter loadings were in the range 0.1-0.97gm(-3)h(-1) for TCE and 0.2-2.12gm(-3)h(-1) for PCE. Under low pollutant loadings, the efficiency of TCE elimination was 23-25% in the bioreactor and 54-70% in the biofilter. The efficiency of PCE elimination was 44-60% in the bioreactor and 50-75% in the biofilter. The best results for the bioreactor were observed one week after the pollutant loading was increased. However, the process did not stabilize. In the next seven days contaminant removal efficiency, enzymatic activity and biomass content were all diminished. PMID:24316808

  4. Aerobic/anaerobic/aerobic sequenced biodegradation of a mixture of chlorinated ethenes, ethanes and methanes in batch bioreactors.

    PubMed

    Frascari, Dario; Fraraccio, Serena; Nocentini, Massimo; Pinelli, Davide

    2013-01-01

    A novel aerobic/anaerobic/aerobic treatment was implemented in batch reactors containing aquifer materials from a site contaminated by tetrachloroethylene (PCE), trichloroethylene (TCE), vinyl chloride (VC), 1,1,2-trichloroethane (1,1,2-TCA) and chloroform (CF). Consortia grown aerobically on methane, propane, n-pentane and n-hexane completely biodegraded the chlorinated solvent mixture, via aerobic cometabolism of VC, CF, TCE and 1,1,2-TCA, followed by PCE reductive dechlorination (RD) to 1,2-cis-dichlorothylene (cis-DCE) or TCE, and cis-DCE/TCE cometabolism in a further aerobic phase. n-Hexane was the best substrate. No electron donor was supplied for RD, which likely utilized cellular material produced during the aerobic phase. Chloride release was stoichiometric with chlorinated solvent biodegradation. According to the Lepidium sativum ecotoxicity test, a decreased toxicity was observed with propane, n-pentane and n-hexane, but not methane. A kinetic study of PCE RD allowed to estimate the PCE maximum specific rate (0.57 ± 0.07 mg mg(protein)(-1) day(-1)) and half-saturation constant (6.7 ± 1.5 mg L(-1)). PMID:23201903

  5. Seed germination and root elongation as indicators of exposure of wetland seedlings to metals

    SciTech Connect

    Sutton, H.D.; Stokes, S.L.; Hook, D.D.; Klaine, S.J. [Clemson Univ., Pendleton, SC (United States)

    1995-12-31

    Wetland ecosystems have often been impacted by the addition of hazardous waste materials. Methods are needed to evaluate the effect of these substances on wetland ecosystems and the organisms within them. This study evaluates the response of various wetland plant species to representative contaminants (cadmium, nickel, atrazine, anthracene, and tetrachloroethylene). Species tested include Caphalanthus occidentalis (buttonbush), Saururus cernuus (lizard`s tail), Liquidambar styraciflua (sweetgum), Sparganium americanum (bur-reed), and Fraxinus pennsylvanica (green ash). To the authors` knowledge these species have rarely if ever been used in toxicological assays. The endpoints used are germination and root elongation. Preliminary studies using a petri dish system have shown decreased germination at the highest metal concentration (50mg/L) and decreased root elongation in the higher metal concentrations (10, 25, and 50mg/L). Interference from the carrier was observed in the organic tests. Root elongation studies using the metals are being continued using tubes with various sand and vermiculite mixes into which freshly germinated seeds are placed. Species with the best responses will be tested in the field at the Savannah River Site, SC, and also with fuel oil. Lettuce (Lactuca saliva) and radish (Raphanus sativus) are being tested alongside the wetland species as reference organisms for which tests are well established.

  6. Health hazard evaluation report HETA 83-369-1672, Lockheed-Georgia Company, Marietta, Georgia

    SciTech Connect

    Salisbury, S.; McConnell, R.; Anger, K.

    1986-02-01

    Working conditions were evaluated in Building 84, at the Lockheed/Georgia Company, Marietta, Georgia where parts removed from C54 aircraft wings were spray-cleaned with 1,1,1-trichloroethane or a solvent blend called Turco T-1000. An authorized representative of the Aeronautical Machinists and Aerospace Workers, Lodge 709, had requested the evaluation to investigate health hazards in Building 84. Air samples taken near an exhaust-ventilation booth were analyzed for solvents. Personal air sampling detected exposures at concentrations well below NIOSH evaluation criteria: 23 parts per million (ppm) 1,1,1-trichloroethane, 350ppm limit; 5.8ppm methylene-chloride, 75ppm limit; 2.8ppm tetrachloroethylene, 50ppm limit; 1.2ppm aromatic hydrocarbons, 25ppm limit; 0.2ppm diacetone-alcohol, 50ppm limit; 0.5ppm n-butanol, 50ppm limit; and 0.2ppm xylene, 100ppm limit. Blood carboxyhemoglobin, total urinary trichloro compounds and m-methyl-hippuric-acid were within or below normal levels. The authors conclude that no solvent exposures above NIOSH recommended levels were detected during the evaluation.

  7. Occurrence of organic wastewater contaminants, pharmaceuticals, and personal care products in selected water supplies, Cape Cod, Massachusetts, June 2004

    USGS Publications Warehouse

    Zimmerman, Marc J.

    2005-01-01

    In June 2004, the U.S. Geological Survey, in cooperation with the Barnstable County Department of Health and Environment, sampled water from 14 wastewater sources and drinking-water supplies on Cape Cod, Massachusetts, for the presence of organic wastewater contaminants, pharmaceuticals, and personal care products. The geographic distribution of sampling locations does not represent the distribution of drinking-water supplies on Cape Cod. The environmental presence of the analyte compounds is mostly unregulated; many of the compounds are suspected of having adverse ecological and human health effects. Of the 85 different organic analyte compounds, 43 were detected, with 13 detected in low concentrations (less than 1 microgram per liter) from drinking-water supplies thought to be affected by wastewater because of previously detected high nitrate concentrations. (Phenol and d-limonene, detected in equipment blanks at unacceptably high concentrations, are not included in counts of detections in this report.) Compounds detected in the drinking-water supplies included the solvent, tetrachloroethylene; the analgesic, acetaminophen; the antibiotic, sulfamethoxazole; and the antidepressant, carbamazapine. Nitrate nitrogen, an indicator of wastewater, was detected in water supplies in concentrations ranging from 0.2 to 8.8 milligrams per liter.

  8. Test plan for single well injection/extraction characterization of DNAPL

    SciTech Connect

    Looney, B.B.; Jerome, K.M.; Burdick, S.; Rossabi, J.; Jarosch, T.R.; Eddy-Dilek, C.A.

    1995-12-01

    Soils and groundwater beneath an abandoned Process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLS, or dense non aqueous Phase liquids. Technologies targeted at the efficient characterization or removal of DNAPL are not currently proven. For example, most DNAPL studies rely on traditional soil and water sampling and the fortuitous observation of immiscible solvent. Once DNAPL is identified, soil excavation (which is only applicable to small contained spill sites) is the only ``proven`` cleanup method. New cleanup approaches based on enhanced removal by surfactants and/or alcohols have been proposed and tested at the pilot scale. As described below, carefully designed experiments similar to the enhanced removal methods may provide important characterization information on DNAPLs.

  9. Physiologically-based pharmacokinetic and toxicokinetic models in cancer risk assessment.

    PubMed

    Krishnan, Kannan; Johanson, Gunnar

    2005-01-01

    Physiologically-based pharmacokinetic (PBPK) and toxicokinetic models are increasingly being used for the conduct of high dose to low dose and interspecies extrapolations required in cancer risk assessment. These models, by simulating tissue dose of toxic chemicals, help address the uncertainty associated with the default approaches for interspecies and high dose to low dose extrapolations. The applicability of PBPK models in cancer risk assessment has been demonstrated with a number of chemicals (e.g., acrylonitrile, 2-butoxyethanol, chloroform, 1,4-dioxane, methyl chloroform, methylene chloride, styrene, trichloroethylene, tetrachloroethylene, vinyl chloride, vinyl acetate). Recent advances in PBPK modeling facilitate the consideration of population distribution of parameter values, age-dependent changes in physiology and metabolism, multi-route exposures as well as multichemical interactions for application in cancer risk assessment. Whereas the average values for various input parameters have been used to evaluate the age-dependency of tissue dose, the Markov Chain Monte Carlo technique can be applied to address variability and uncertainty in parameter estimates, thus facilitating a more accurate estimation of cancer risk in the population. The PBPK models also uniquely facilitate the simulation of tissue dose, and thereby cancer risks, associated with multi-route and multichemical exposure situations. Overall, the recent advances reviewed in this article point to the continued enhancement of the scientific basis and applicability of PBPK models in cancer risk assessment. PMID:16291521

  10. INTERNAL REFLECTION SENSOR FOR THE CONE PENETROMETER

    SciTech Connect

    Job M. Bello

    1999-05-01

    The objective of this project is to fabricate and demonstrate an internal reflection sensor (IRS) prototype for the cone penetrometer. The IRS is a sensor that responds in real-time to almost any subsurface liquid contaminants. The IRS utilizes the variations of refractive index of different liquid contaminants as a sensing scheme. All the project objectives have been successfully met during the period of the program. A prototype IRS that can be easily integrated into a cone penetrometer was designed and fabricated in the first phase of the program. A controlled field evaluation of the IRS was also conducted during the first phase and results showed that the IRS was capable of locating NAPLs in soil. In the second phase of the program, the IRS was evaluated in the field and pushed into the ground using an actual cone penetrometer system. The IRS was evaluated at known contamination sites at the Savannah River Site and a commercial site in Jacksonville, Florida. Results of the field deployment of the IRS indicated that the sensor was able to sense the location of contaminants such as tetrachloroethylene in the subsurface.

  11. Field test of single well DNAPL characterization using alcohol injection/extraction

    SciTech Connect

    Jerome, K.M.; Looney, B.B.; Rhoden, M.L.; Riha, B.; Burdick, S. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1996-10-29

    Soils and groundwater beneath an abandoned process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLs, or dense non-aqueous phase liquids. Technologies targeted at efficient characterization or removal of DNAPL are not currently proven. The authors performed injection/extraction characterization tests in six existing wells in A/M Area. Water concentrations for TCE and/or PCE in these wells ranged from 0% to 100% of solubility. For each test, small amounts of solubilizing solution were used to try to confirm or deny the presence or absence of DNAPL in the immediate vicinity of the well screen.

  12. Polymer coating behavior of Rayleigh-SAW resonators with gold electrode structure for gas sensor applications.

    PubMed

    Avramov, Ivan D; Länge, Kerstin; Rupp, Swen; Rapp, Bastian; Rapp, Michael

    2007-01-01

    Results from systematic polymer coating experiments on surface acoustic wave (SAW) resonators and coupled resonator filters (CRF) on ST-cut quartz with a corrosion-proof electrode structure entirely made of gold (Au) are presented and compared with data from similar SAW devices using aluminium (Al) electrodes. The recently developed Au devices are intended to replace their earlier Al counterparts in sensor systems operating in highly reactive chemical gas environments. Solid parylene C and soft poly[chlorotrifluoroethylene-co-vinylidene fluoride] (PCFV) polymer films are deposited under identical conditions onto the surface of Al and Au devices. The electrical performance of the Parylene C coated devices is monitored online during film deposition. The PCVF coated devices are evaluated after film deposition. The experimental data show that the Au devices can stand up to 40% thicker solid films for the same amount of loss increase than the Al devices and retain better resonance and phase characteristics. The frequency sensitivities of Au and Al devices to parylene C deposition are nearly identical. After coating with soft PCFV sensing film, the Au devices provide up to two times higher gas sensitivity when probed with cooling agent, octane, or tetrachloroethylene. PMID:17225810

  13. Sanitary Landfill 1991 annual groundwater monitoring report

    SciTech Connect

    Thompson, C.Y.; Norrell, G.T.; Bennett, C.B.

    1992-02-01

    The Savannah River Site (SRS) Sanitary Landfill is an approximately seventy acre site located just south of SRS Road C between the Savannah River Site`s B-Area and Upper Three Runs Creek. Results from the first through third quarter 1991 groundwater monitoring date continue to show evidence of elevated levels of several hazardous constituents beneath the Sanitary Landfill: tritium, vinyl chloride, total radium, cadmium, 1,1,1-trichloroethane, 1,2 dichloroethane, 1,4 dichlorobenzene, trichloroethylene (TCE), tetrachloroethylene, and 1,1 dichloroethylene in excess of the primary drinking water standards were observed in at least one well monitoring the Sanitary Landfill during the third quarter of 1991. All of these constituents, except radium, were observed in the lower half of the original thirty-two acre site or the southern expansion site. Trichloroethylene and vinyl chloride are the primary organic contaminants in groundwater beneath the Sanitary Landfill. Vinyl chloride has become the primary contaminant during 1991. Elevated levels of benzene were consistently detected in LFW 7 in the past, but were not present in any LFW wells during the third quarter of 1991. A minor tritium plume is present in the central part of original thirty-two acre landfill. Elevated levels of tritium above the PDWS were consistently present in LFW 10A through 1991. This well has exhibited elevated tritium activities since the second quarter of 1989. Contaminant concentrations in the Sanitary Landfill are presented and discussed in this report.

  14. Sanitary Landfill 1991 annual groundwater monitoring report

    SciTech Connect

    Thompson, C.Y.; Norrell, G.T.; Bennett, C.B.

    1992-02-01

    The Savannah River Site (SRS) Sanitary Landfill is an approximately seventy acre site located just south of SRS Road C between the Savannah River Site's B-Area and Upper Three Runs Creek. Results from the first through third quarter 1991 groundwater monitoring date continue to show evidence of elevated levels of several hazardous constituents beneath the Sanitary Landfill: tritium, vinyl chloride, total radium, cadmium, 1,1,1-trichloroethane, 1,2 dichloroethane, 1,4 dichlorobenzene, trichloroethylene (TCE), tetrachloroethylene, and 1,1 dichloroethylene in excess of the primary drinking water standards were observed in at least one well monitoring the Sanitary Landfill during the third quarter of 1991. All of these constituents, except radium, were observed in the lower half of the original thirty-two acre site or the southern expansion site. Trichloroethylene and vinyl chloride are the primary organic contaminants in groundwater beneath the Sanitary Landfill. Vinyl chloride has become the primary contaminant during 1991. Elevated levels of benzene were consistently detected in LFW 7 in the past, but were not present in any LFW wells during the third quarter of 1991. A minor tritium plume is present in the central part of original thirty-two acre landfill. Elevated levels of tritium above the PDWS were consistently present in LFW 10A through 1991. This well has exhibited elevated tritium activities since the second quarter of 1989. Contaminant concentrations in the Sanitary Landfill are presented and discussed in this report.

  15. Advanced oxidation processes. Test of a kinetic model for the oxidation of organic compounds with ozone and hydrogen peroxide in a semibatch reactor

    SciTech Connect

    Glaze, W.H.; Kang, J.W.

    1989-01-01

    Experimental data are presented to test a kinetic model of the OE/H{sub 2}O{sub 2} process in a semibatch reactor. The effect of bicarbonate and carbonate ions is measured and found to be in concurrence with model predictions. The effect of pH in the ozone mass-transfer-limited region was examined in bicarbonate-spiked distilled water. Since the reaction is mass transfer limited, the primary effect above pH 7 is the result of changes in the distribution of inorganic carbon species which are OH-radical scavengers. Below pH 7, there is a lag period during which ozone and peroxide increase until the chain reaction begins. The effects of chloride ion and the concentration of radical scavengers other than carbonate species in ground waters are also measured. The mass-transfer/reaction rate model has been used to estimate rate constants for the reaction of hydroxyl radicals with trichloroethylene, 1,2-dibromoethane, 1,2-dibromo-3-chloropropane, carbon tetrachloride, and two bicyclic alcohols, 2-methylisoborneol and geosmin. While the model developed for the distilled water system was successful in predicting the rate of tetrachloroethylene (PCE) oxidation and the concentration of residual ozone and peroxide in regions I and III, respectively, there are several features of the model that remain unresolved when the matrix is changed to a real surface or ground water. This and subsequent papers will investigate these effects.

  16. Malignant Tumors of the Female Reproductive System

    PubMed Central

    Labrèche, France

    2012-01-01

    This review summarizes the epidemiology of cancer of the female reproductive system and associated lifestyle factors. It also assesses the available evidence for occupational factors associated with these cancers. Cervical, endometrial, and ovarian cancers are relatively common, and cause significant cancer morbidity and mortality worldwide, whereas vulvar, vaginal, fallopian tube cancers, and choriocarcinomas are very rare. As several lifestyle factors are known to play a major role in the etiology of these cancers, very few published studies have investigated possible relationships with occupational factors. Some occupational exposures have been associated with increased risks of these cancers, but apart from the available evidence on the relationships between asbestos fibers and ovarian cancer, and tetrachloroethylene and cervical cancer, the data is rather scarce. Given the multifactorial nature of cancers of the female reproductive system, it is of the utmost importance to conduct occupational studies that will gather detailed data on potential individual confounding factors, in particular reproductive history and other factors that influence the body's hormonal environment, together with information on socio-economic status and lifestyle factors, including physical activity from multiple sources. Studies on the mechanisms of carcinogenesis in the female reproductive organs are also needed in order to elucidate the possible role of chemical exposures in the development of these cancers. PMID:23019529

  17. Membrane-extraction ion mobility spectrometry for in situ detection of chlorinated hydrocarbons in water.

    PubMed

    Du, Yongzhai; Zhang, Wei; Whitten, William; Li, Haiyang; Watson, David B; Xu, Jun

    2010-05-15

    Membrane-extraction ion mobility spectrometry (ME-IMS) has been developed for in situ sampling and analysis of trace chlorinated hydrocarbons in water in a single procedure. The sampling is configured so that aqueous contaminants permeate through a spiral hollow poly(dimethylsiloxane) (PDMS) membrane and are carried away by a vapor flow through the membrane tube. The extracted analyte flows into an atmospheric-pressure chemical-ionization (APCI) chamber and is analyzed in a specially made IMS analyzer. The PDMS membrane was found to effectively extract chlorinated hydrocarbon solvents from the liquid phase to vapor. The specialized IMS analyzer has measured resolutions of R = 33 and 41, respectively, for negative- and positive-modes and is capable of detecting aqueous tetrachloroethylene (PCE) and trichloroethylene (TCE) as low as 80 and 74 microg/L in the negative ion mode, respectively. The time-dependent characteristics of sampling and detection of TCE are both experimentally and theoretically studied for various concentrations, membrane lengths, and flow rates. These characteristics demonstrate that membrane-extraction IMS is feasible for the continuous monitoring of chlorinated hydrocarbons in water. PMID:20334385

  18. Research to Support the Determination of Spacecraft Maximum Acceptable Concentrations of Potential Atmospheric Contaminants

    NASA Technical Reports Server (NTRS)

    Orr, John L.

    1997-01-01

    In many ways, the typical approach to the handling of bibliographic material for generating review articles and similar manuscripts has changed little since the use of xerographic reproduction has become widespread. The basic approach is to collect reprints of the relevant material and place it in folders or stacks based on its dominant content. As the amount of information available increases with the passage of time, the viability of this mechanical approach to bibliographic management decreases. The personal computer revolution has changed the way we deal with many familiar tasks. For example, word processing on personal computers has supplanted the typewriter for many applications. Similarly, spreadsheets have not only replaced many routine uses of calculators but have also made possible new applications because the cost of calculation is extremely low. Objective The objective of this research was to use personal computer bibliographic software technology to support the determination of spacecraft maximum acceptable concentration (SMAC) values. Specific Aims The specific aims were to produce draft SMAC documents for hydrogen sulfide and tetrachloroethylene taking maximum advantage of the bibliographic software.

  19. Toxic hazards research unit annual report 1993. Final report, 1 October 1992-30 September 1993

    SciTech Connect

    Dodd, D.E.; Smith, P.M.

    1994-10-01

    This report presents a review of the activities of the Toxic Hazards Research Unit (THRU) for the period 0 1 October 1992 through 30 September 1993. The THRU conducts descriptive, mechanistic, and predictive toxicology research and toxicological risk assessments to provide data to predict health hazards and to assess health risks associated with human exposure to chemicals and materials associated with military systems and operational environments. The report includes summaries of ongoing or completed research activities for the individual toxicology research requirements of the U.S. Air Force, Army, and Navy; highlights of the research support elements and conference activities of the THRU; and appendices that describe the THRU organization and its publications and presentations. The majority of the report describes the progress attained in toxicological studies on a wide variety of chemicals and materials to include tetrachloroethylene, iodotrifluoromethane, ammonium dinitramide, HCFC- 123, trichloroethylene, toluene, liquid propellant formulation 1846, vinyl chloride and trichloroethylene mixture, methylene chloride, MIL-H-19457C hydraulic fluid, acrolein and acrolein/Syloid 244 mixture, 1 ,3,3-trinitroazetidine, and 1,3,5-trinitrobenzene. The THRU also conducted research on lactational transfer and dermal absorption of chemicals, on toxicological risk assessment methods, and evaluated statistical methods for assessing military populations as a subgroup of the public at-large.

  20. Chlorinated organic compounds in ground water at Roosevelt Field, Nassau County, Long Island, New York

    USGS Publications Warehouse

    Eckhardt, D.A.; Pearsall, K.A.

    1989-01-01

    Trichloroethylene (TCE), 1,2-dichloroethylene (DCE), and tetrachloroethylene (PCE) have been detected in water from five public-supply wells and six cooling-water wells that tap the Magothy aquifer at Roosevelt Field, a 200-acre area that is now a large shopping mall and office-building complex. The cooling water is discharged after use to the water table (upper glacial) aquifer through a nearby recharge basin and a subsurface drain field. Three plumes of TCE in groundwater have been delineated--the source plume, which has penetrated both aquifers , and two more recent plumes emanating from the two discharge sites in the water-table aquifer. Concentrations of inorganic constituents in the three plumes are the same as those in ambient water in the area. The two secondary plumes discharged cooling water extended at least 1,000 ft south-southeastward in the direction of regional groundwater flow. Pumping at wells screened in the middle and basal sections of the Magothy aquifers, where clay layers are absent and sandy zones provide good vertical hydraulic connection within the aquifer system, has increased the rate of downward contaminant advection. The transient increases in downward movement are cumulative over time and have brought TCE to the bottom of the Magothy aquifer, 500 ft below land surface. (USGS)

  1. Plume and lithologic profiling with surface resistivity and seismic tomography.

    PubMed

    Watson, David B; Doll, William E; Gamey, T Jeffrey; Sheehan, Jacob R; Jardine, Philip M

    2005-01-01

    Improved surface-based geophysical technologies that are commercially available provide a new level of detail that can be used to guide ground water remediation. Surface-based multielectrode resistivity methods and tomographic seismic refraction techniques were used to image to a depth of approximately 30 m below the surface at the Natural and Accelerated Bioremediation Research Field Research Center. The U.S. Department of Energy (DOE) established the research center on the DOE Oak Ridge Reservation in Oak Ridge, Tennessee, to conduct in situ field-scale studies on bioremediation of metals and radionuclides. Bioremediation studies are being conducted on the saprolite, shale bedrock, and ground water at the site that have been contaminated with nitrate, uranium, technetium, tetrachloroethylene, and other contaminants (U.S. DOE 1997). Geophysical methods were effective in imaging the high-ionic strength plume and in defining the transition zone between saprolite and bedrock zones that appears to have a significant influence on contaminant transport. The geophysical data were used to help select the location and depth of investigation for field research plots. Drilling, borehole geophysics, and ground water sampling were used to verify the surface geophysical studies. PMID:15819938

  2. L-Area Reactor - 1993 annual - groundwater monitoring report

    SciTech Connect

    Chase, J.A.

    1994-09-01

    Groundwater was sampled and analyzed during 1993 from wells monitoring the water table at the following locations in L Area: the L-Area Acid/Caustic Basin (four LAC wells), L-Area Research Wells in the southern portion of the area (outside the fence; three LAW wells), the L-Area Oil and Chemical Basin (four LCO wells), the L-Area Disassembly Basin (two LDB wells), the L-Area Burning/Rubble Pit (four LRP wells), and the L-Area Seepage Basin (four LSB wells). During 1993, tetrachloroethylene was detected above its drinking water standard (DWS) in the LAC, LAW, LCO, and LDB well series. Lead exceeded its 50 {mu}g/L standard in the LAW, LDB, and LRP series, and tritium was above its DWS in the LAW, LCO, and LSB series. Apparently anomalous elevated levels of the common laboratory contaminant bis(2-ethylhexyl)phthalate were reported during first quarter in one well each in the LAC series and LCO series, and during third quarter in a different LCO well. Extensive radionuclide analyses were performed during 1993 in the LAC, LAW, and LCO well series. No radionuclides other than tritium were reported above DWS or Flag 2 criteria.

  3. Health assessment for Garden State Cleaners Company, Buena Borough, Atlantic City, New Jersey, Region 2. CERCLIS No. NJD053280160. Final report

    SciTech Connect

    Not Available

    1990-09-28

    The Garden State Cleaners Company is a dry cleaning establishment located in Buena Borough, New Jersey. Contaminated wastewater from on-site operations was routinely discharged to on-site soils. Analytical data has described significant soil and ground-water contamination from tetrachloroethylene (PCE) and other volatile organic compounds. Ground-water contamination downgradient (to the south) of the site has required the recommended closing of private wells and the installation of a municipal water supply system. An Administrative Order and Notice of Civil Administrative Penalty Assessment (AO and PSO) were issued to Garden State Cleaners in December 1985, requiring GSC to perform a full RI/FS. Municipal water supplies have been made available to affected residens, but utilization is elective. The site was included on the NPL list in March 1989 and is currently ranked 105 of 108 sites in New Jersey. ATSDR and NJDOH consider the Garden State Cleaners site to be of public health concern. The site is being considered for follow-up health study or evaluation.

  4. Stability of nitrate-ion in simulated deposition samples used for quality-assurance activities by the U. S. Geological Survey

    SciTech Connect

    Eckhardt, D.A.V.; Pearsall, K.A.

    1989-01-01

    Trichloroethylene (TCE), 1,2-dichloroethylene (DCE), and tetrachloroethylene (PCE) have been detected in water from five public-supply wells and six cooling-water wells that tap the Magothy aquifer at Roosevelt Field. The cooling water is discharged after use to the water table aquifer through a nearby recharge basin and a subsurface drain field. Three plumes of TCE in groundwater have been delineated - the source plume, which has penetrated both aquifers, and two more recent plumes emanating from the two discharge sites in the water-table aquifer. Concentrations of inorganic constituents in the three plumes are the same as those in ambient water in the area. The two secondary plumes discharged cooling water extended at least 1,000 ft south-southeastward in the direction of regional groundwater flow. Pumping at wells screened in the middle and basal sections of the Magothy aquifers, where clay layers are absent and sandy zones provide good vertical hydraulic connection within the aquifer system, has increased the rate of downward contaminant advection. The transient increases in downward movement are cumulative over time and have brought TCE to the bottom of the Magothy aquifer, 500 ft below land surface. 38 refs., 11 figs., 8 tabs.

  5. Groundwater quality assessment/corrective action feasibility plan. Savannah River Laboratory Seepage Basins

    SciTech Connect

    Stejskal, G.F.

    1989-11-15

    The Savannah River Laboratory (SRL) Seepage Basins are located in the northeastern section of the 700 Area at the Savannah River Site. Currently the four basins are out of service and are awaiting closure in accordance with the Consent Decree settled under Civil Act No. 1:85-2583. Groundwater monitoring data from the detection monitoring network around the SRL Basins was recently analyzed using South Carolina Hazardous Waste Management Regulations R.61-79.264.92 methods to determine if groundwater in the immediate vicinity of the SRL Basins had been impacted. Results from the data analysis indicate that the groundwater has been impacted by both volatile organic constituents (VOCs) and inorganic constituents. The VOCs, specifically trichloroethylene and tetrachloroethylene, are currently being addressed under the auspices of the SRS Hazardous Waste Permit Application (Volume III, Section J.6.3). The impacts resulting from elevated levels of inorganic constituent, such as barium, calcium, and zinc in the water table, do not pose a threat to human health and the environment. In order to determine if vertical migration of the inorganic constituents has occurred three detection monitoring wells are proposed for installation in the upper portion of the Congaree Aquifer.

  6. Groundwater quality assessment/corrective action feasibility plan

    SciTech Connect

    Stejskal, G.F.

    1989-11-15

    The Savannah River Laboratory (SRL) Seepage Basins are located in the northeastern section of the 700 Area at the Savannah River Site. Currently the four basins are out of service and are awaiting closure in accordance with the Consent Decree settled under Civil Act No. 1:85-2583. Groundwater monitoring data from the detection monitoring network around the SRL Basins was recently analyzed using South Carolina Hazardous Waste Management Regulations R.61-79.264.92 methods to determine if groundwater in the immediate vicinity of the SRL Basins had been impacted. Results from the data analysis indicate that the groundwater has been impacted by both volatile organic constituents (VOCs) and inorganic constituents. The VOCs, specifically trichloroethylene and tetrachloroethylene, are currently being addressed under the auspices of the SRS Hazardous Waste Permit Application (Volume III, Section J.6.3). The impacts resulting from elevated levels of inorganic constituent, such as barium, calcium, and zinc in the water table, do not pose a threat to human health and the environment. In order to determine if vertical migration of the inorganic constituents has occurred three detection monitoring wells are proposed for installation in the upper portion of the Congaree Aquifer.

  7. Characterization and simulation of fate and transport of selected volatile organic compounds in the vicinities of the Hadnot Point Industrial Area and landfill: Chapter A Supplement 6 in Analyses and historical reconstruction of groundwater flow, contaminant fate and transport, and distribution of drinking water within the service areas of the Hadnot Point and Holcomb Boulevard Water Treatment Plants and vicinities, U.S. Marine Corps Base Camp Lejeune, North Carolina

    USGS Publications Warehouse

    Jones, L. Elliott; Suárez-Soto, René J.; Anderson, Barbara A.; Maslia, Morris L.

    2013-01-01

    This supplement of Chapter A (Supplement 6) describes the reconstruction (i.e. simulation) of historical concentrations of tetrachloroethylene (PCE), trichloroethylene (TCE), and benzene3 in production wells supplying water to the Hadnot Base (USMCB) Camp Lejeune, North Carolina (Figure S6.1). A fate and transport model (i.e., MT3DMS [Zheng and Wang 1999]) was used to simulate contaminant migration from source locations through the groundwater system and to estimate mean contaminant concentrations in water withdrawn from water-supply wells in the vicinity of the Hadnot Point Industrial Area (HPIA) and the Hadnot Point landfill (HPLF) area.4 The reconstructed contaminant concentrations were subsequently input into a flow-weighted, materials mass balance (mixing) model (Masters 1998) to estimate monthly mean concentrations of the contaminant in finished water 5 at the HPWTP (Maslia et al. 2013). The calibrated fate and transport models described herein were based on and used groundwater velocities derived from groundwater-flow models that are described in Suárez-Soto et al. (2013). Information data pertinent to historical operations of water-supply wells are described in Sautner et al. (2013) and Telci et al. (2013).

  8. Interpretation of Borehole Geophysical Logs at Area C, Former Naval Air Warfare Center, Warminster Township, Bucks County, Pennsylvania, 2007

    USGS Publications Warehouse

    Sloto, Ronald A.

    2008-01-01

    This study was done by the U.S. Geological Survey in cooperation with the U.S. Navy at Area C of the former Naval Air Warfare Center in Warminster Township, Bucks County, Pa., in support of hydrogeological investigations conducted by the Navy to address ground-water contamination in the Stockton Formation. Borehole geophysical logs were collected, heatpulse-flowmeter measurements were made, and borehole television surveys were run in seven boreholes ranging from 31 to 75 feet deep. Caliper logs and borehole television surveys were used to identify fractures and the location of possible water-bearing zones. Heatpulse-flowmeter measurements were used to identify fractures that were water-bearing zones. Natural-gamma and single-point-resistance logs were used to correlate lithology across the area. Elevated concentrations of tetrachloroethylene (PCE) were measured in water samples from wells with water-bearing zones in the interval of the aquifer where monitor well HN-23A is screened. Water samples from wells with water-bearing zones above or below this interval had substantially lower concentrations of PCE. Wells screened in this interval yielded less than 0.5 gallon per minute, indicating that the interval has low permeability; this may account for the small areal extent and slow migration of PCE.

  9. Chemical oxidation of volatile and semi-volatile organic compounds in soil

    SciTech Connect

    Gates, D.D.; Siegrist, R.L.; Cline, S.R.

    1995-06-01

    Subsurface contamination with fuel hydrocarbons or chlorinated hydrocarbons is prevalent throughout the Department of Energy (DOE) complex and in many sites managed by the Environmental Protection Agency (EPA) Superfund program. The most commonly reported chlorinated hydrocarbons (occurring > 50% of DOE contaminated sites) were trichloroethylene (TCE), 1, 1, 1,-trichloroethane (TCA), and tetrachloroethylene (PCE) with concentrations in the range of 0.2 {mu}g/kg to 12,000 mg/kg. The fuel hydrocarbons most frequently reported as being present at DOE sites include aromatic compounds and polyaromatic compounds such as phenanthrene, pyrene, and naphthalene. The primary sources of these semi-volatile organic compounds (SVOCs) are coal waste from coal fired electric power plants used at many of these facilities in the past and gasoline spills and leaks. Dense non-aqueous phase liquids (DNAPLs) can migrate within the subsurface for long periods of time along a variety of pathways including fractures, macropores, and micropores. Diffusion of contaminants in the non-aqueous, aqueous, and vapor phase can occur from the fractures and macropores into the matrix of fine-textured media. As a result of these contamination processes, removal of contaminants from the subsurface and the delivery of treatment agents into and throughout contaminated regions are often hindered, making rapid and extensive remediation difficult.

  10. Risk communication: Health risks associated with environmentally contaminated private wells versus chloroform in a public water supply

    SciTech Connect

    Sidhu, K.S.; Chadzynski, L. (Michigan Dept. of Public Health, Lansing, MI (United States))

    1994-06-01

    During March 1988, 16 private wells in Sault St. Marie, Michigan, were found to be contaminated with one or more environmental contaminants. Risk assessments for carcinogens (benzene, 1,2-dichloroethane, dichloromethane, trichloroethylene, and tetrachloroethylene) were formulated. The maximum concentration of chloroform in the city public water supply was 26 [mu]g/L. The relative health risk from the consumption of chlorinated surface water from the public water supply system would be approximately 4.3 times greater compared to that of consuming groundwater from the contaminated private wells. The affected residents were given three options: (a) continue consumption of bottled water; (b) connection to the existing public water supply system; or (c) construction of deep water wells. The citizens voted for the second option of connecting to the public water supply system and voluntarily accepted the relatively higher health risk. The State of Michigan later proposed to further improve the water purity by upgrading the public water supply system by the incorporation of a filtration plant. The project was completed in August 1993.

  11. Metallurgical Laboratory Hazardous Waste Management Facility groundwater monitoring report. Fourth quarter 1993 and 1993 summary

    SciTech Connect

    Not Available

    1994-03-01

    The AMB wells at the Metallurgical Laboratory Hazardous Waste Management Facility (Met Lab HWMF) are monitored for selected constituents to comply with the Natural Resources Defense council et al. Consent Decree of May 1988 that identifies the Met Lab HWMF as subject to the Resource Conservation and Recovery Act. In addition, the wells are monitored, as requested, for other constituents as part of the Savannah River Site (SRS) Groundwater Monitoring Program. During the fourth quarter 1993, samples from AMB groundwater monitoring wells at the Metallurgical Laboratory Hazardous Waste Management Facility were analyzed for selected heavy metals, indicator parameters, radionuclides, volatile organic compounds, and other constituents. Six parameters exceeded standards during the quarter. As in previous quarters, dichloromethane (methylene chloride), tetrachloroethylene, and trichloroethylene exceeded final Primary Drinking Water Standards; pH, specific conductance, and total organic halogens exceeded the Savannah River Site Flag 2 criteria in one or more of the wells. Groundwater flow direction and rate in the water-table unit were similar to previous quarters.

  12. Volatile chlorinated hydrocarbons in Antarctic superficial snow sampled during Italian ITASE expeditions.

    PubMed

    Zoccolillo, Lelio; Amendola, Luca; Cafaro, Claudia; Insogna, Susanna

    2007-05-01

    In order to detect the presence of some volatile chlorinated hydrocarbons (VCHCs) and to understand their transport and deposition mechanism, superficial snow was sampled during two Italian ITASE (International Trans Antarctic Scientific Expedition) expeditions: the first traverse was carried out in 1998/1999 from Terra Nova Bay to Dome Concordia; the second traverse was carried out in 2001/2002 through Adélie, George V, Oates and Northern Victoria Lands. Some VCHCs (chloroform; 1,1,1-trichloroethane; tetrachloromethane; 1,1,2-trichloroethylene; tetrachloroethylene) were analysed using a highly sensitive and selective hyphenated technique composed of a purge-and-trap injector coupled to a gas chromatograph with a mass spectrometric detector (PTI-GC-MS) operating in SIM mode. Investigated VCHCs were present in all analysed snow samples with concentration levels of several units, tens, or sometimes hundreds of ng kg(-1). VCHC snow concentration levels remained approximately constant with changing distance from the coast and the comparison between fresh and aged snow did not show any substantial differences; on the basis of this evidence marine aerosol and dry deposition may be rejected as principal VCHC transport and deposition mechanism hypotheses. VCHC concentration levels in Antarctic snow samples were comparable to or greater than those found in snow from temperate zones. PMID:17287006

  13. Time series geophysical monitoring of permanganate injections and in situ chemical oxidation of PCE, OU1 area, Savage Superfund Site, Milford, NH, USA

    USGS Publications Warehouse

    Harte, Philip T.; Smith, Thor E.; Williams, John H.; Degnan, James R.

    2012-01-01

    In situ chemical oxidation (ISCO) treatment with sodium permanganate, an electrically conductive oxidant, provides a strong electrical signal for tracking of injectate transport using time series geophysical surveys including direct current (DC) resistivity and electromagnetic (EM) methods. Effective remediation is dependent upon placing the oxidant in close contact with the contaminated aquifer. Therefore, monitoring tools that provide enhanced tracking capability of the injectate offer considerable benefit to guide subsequent ISCO injections. Time-series geophysical surveys were performed at a superfund site in New Hampshire, USA over a one-year period to identify temporal changes in the bulk electrical conductivity of a tetrachloroethylene (PCE; also called tetrachloroethene) contaminated, glacially deposited aquifer due to the injection of sodium permanganate. The ISCO treatment involved a series of pulse injections of sodium permanganate from multiple injection wells within a contained area of the aquifer. After the initial injection, the permanganate was allowed to disperse under ambient groundwater velocities. Time series geophysical surveys identified the downward sinking and pooling of the sodium permanganate atop of the underlying till or bedrock surface caused by density-driven flow, and the limited horizontal spread of the sodium permanganate in the shallow parts of the aquifer during this injection period. When coupled with conventional monitoring, the surveys allowed for an assessment of ISCO treatment effectiveness in targeting the PCE plume and helped target areas for subsequent treatment.

  14. Modeling acute and chronic toxicity of nonpolar narcotic chemicals and mixtures to Ceriodaphnia dubia.

    PubMed

    Niederlehner, B R; Cairns, J; Smith, E P

    1998-02-01

    The response of the daphnid Ceriodaphnia dubia to six widely used industrial chemicals acting through nonpolar narcosis and a mixture was determined. Toxicological effect levels were based on reasonably steady-state, measured concentrations. Reproductive IC50S were 149 microM benzene, 82 microM trichloroethylene, 35 microM toluene, 31 microM ethylbenzene, 26 microM m-xylene, and 4 microM tetrachloroethylene. A QSAR describing 2-day LC50S as a function of log Kow accounted for 90.97% of the variation in response across chemical. A similar QSAR for chronic effects on reproduction accounted for 78.92%. Mixtures of benzene, trichloroethylene, and toluene had effects at concentrations below their individual LOELs. Observed effects of 20/24 mixtures tested fell within the 95% prediction interval for a concentration-addition model of joint action derived from tests with individual components. However, the observed response differed significantly from the predictive relationship. In general, the predictive relationship overestimated mixture toxicity. Fitted relationships reduced observed error by as much as 82% compared to the predictive model. PMID:9515086

  15. Development of CFC-Free Cleaning Processes at the NASA White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Beeson, Harold; Kirsch, Mike; Hornung, Steven; Biesinger, Paul

    1995-01-01

    The NASA White Sands Test Facility (WSTF) is developing cleaning and verification processes to replace currently used chlorofluorocarbon-113- (CFC-113-) based processes. The processes being evaluated include both aqueous- and solvent-based techniques. The presentation will include the findings of investigations of aqueous cleaning and verification processes that are based on a draft of a proposed NASA Kennedy Space Center (KSC) cleaning procedure. Verification testing with known contaminants, such as hydraulic fluid and commonly used oils, established correlations between nonvolatile residue and CFC-113. Recoveries ranged from 35 to 60 percent of theoretical. WSTF is also investigating enhancements to aqueous sampling for organics and particulates. Although aqueous alternatives have been identified for several processes, a need still exists for nonaqueous solvent cleaning, such as the cleaning and cleanliness verification of gauges used for oxygen service. The cleaning effectiveness of tetrachloroethylene (PCE), trichloroethylene (TCE), ethanol, hydrochlorofluorocarbon-225 (HCFC-225), tert-butylmethylether, and n-Hexane was evaluated using aerospace gauges and precision instruments and then compared to the cleaning effectiveness of CFC-113. Solvents considered for use in oxygen systems were also tested for oxygen compatibility using high-pressure oxygen autoignition and liquid oxygen mechanical impact testing.

  16. Development of a method for assessing the toxicity of volatile organic contaminants (VOCs) to soil biota

    SciTech Connect

    Cureton, P.M. [Environment Canada, Ottawa, Ontario (Canada). Evaluation and Interpretation Branch; Lintott, D.; Balch, G.; Goudey, S. [HydroQual Labs. Ltd., Calgary, Alberta (Canada)

    1994-12-31

    A method was developed to assess the toxicity of VOCs to plants and earthworms (survival of Eisenia foetida). The procedures followed were based on Greene et al. Gas samples for head space analyses were removed, at test initiation a termination, through a bulkhead fitting in the lid equipped with septa. Treatment levels were prepared, at low temperature to minimize volatilization, by spiking a soil sample with the compound of interest and then serially diluting it with clean soil. Root elongation tests were conducted on filter paper supported by 70 mesh silica sand spiked with the volatile of interest. Soils were then inundated with water, shaken with heating, and the headspace reanalyzed for the total contaminant concentration in the test system (total equals headspace plus adsorbed). Enclosing the seeds and worms in containers did not appear to have detrimental effects. VOCs tested included benzene, xylene, toluene, ethylbenzene, tetrachloroethylene, and 1,1,2-trichloroethylene. Each test was repeated three times with different batches of soil, seed lots and worms from different colonies. Endpoints derived based on nominal and measured concentrations included: NOEC, LOEC, LC{sub 50} and LC{sub 25} for earthworm mortality and EC{sub 50} and EC{sub 25} for emergence and root elongation.

  17. Biological reductive dechlorination of chlorinated ethylenes: Implications for natural attenuation and biostimulation

    SciTech Connect

    Distefano, T.D. [Pennsylvania State Univ., Harrisburg, PA (United States)

    1995-12-31

    Chlorinated organic compounds are the most frequently found contaminants at many hazardous waste sites and industrial facilities. Numerous industries use chlorinated organics such as tetrachloroethylene also known as perchloroethylene (PCE) -- and trichloroethylene (TCE), as degreasing agents, paint strippers, and in textile processing. These solvents are often detected as soil and ground water contaminants due to improper storage and disposal practices. Laboratory and full-scale investigations have proven that complete biological transformation of PCE and TCE is possible under anaerobic conditions. Biological treatment of chlorinated ethenes has received much interest due to the prevalence of these contaminants and the need to develop technologies that destroy contaminants rather than transfer them to other media. The purpose of this paper is to give an overview of the biological process by which anaerobic bacteria biodegrade chlorinated ethylenes. The benefits of this process are discussed along with key findings that may be employed to determine if dechlorination is occurring under natural conditions. Requirements of these bacteria are described and an assessment of future research needs is provided.

  18. Health assessment for Whitmoyer Laboratories, Jackson Township, Lebanon County, Pennsylvania, Region 3. CERCLIS No. PAD003005014. Preliminary report

    SciTech Connect

    Not Available

    1988-11-17

    The Whitmoyer Laboratories 17.5-acre site is formerly an animal arsenical pharmaceutical manufacturing facility that operated from 1934 to 1984. In the early 1960s, approximately four million pounds of soluble arsenic wastes were placed into unlined lagoons. The environmental contamination on-site consists of arsenic and aniline in solid material in the concrete vault; arsenic, anile, 1,1-trichloroethane, and trans-1,2-dichloroethene in groundwater; arsenic in soil; and arsenic in surface water. Contamination off-site consists of arsenic, aniline, 1,1,1-trichloroethane in groundwater from an industrial well; arsenic in surface water; and arsenic in sediment. In addition, extensive sampling of domestic and industrial wells off-site has found arsenic, aniline, 1,2-dichloroethane, trans-1,2-dichloroethylene, trichloroethylene, 1,1,1-trichloroethane, and tetrachloroethylene. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via contaminated groundwater, surface water, sediment, soil, and possibly air.

  19. Serial reaction modeling using random walk particles tracking methods

    NASA Astrophysics Data System (ADS)

    Henri, C.; Fernández-Garcia, D.

    2012-04-01

    Since the middle of the previous century, DNAPL contamination is a clear identified problem for the management of urban and suburban groundwater resources quality. Random walk particles tracking methods showed their legitimacy and efficiency for modeling reactive transport especially thanks to the absence of numerical dispersion and computational efficiency. We present a new method to efficiently simulate a serial reaction, i.e., the natural degradation of chlorinated solvents, into a trustable 3D random walk particle-tracking model (RW3D). The chemical specie is defined as a particle property (state of the particle). Results of the zeroth spatial moment of the mass transfer equation derivation in the Fourier domain are used as particle state transition probabilities. We obtain thereby the state of a particle after a given time i.e. the mass evolution of the different species involved into the serial reaction. The particle tracking approach is successfully compared to the well- known finite difference code RT3D. We apply this approach to model the behavior of chlorinated compounds resulting from the sequential degradation of tetrachloroethylene (PCE) in highly randomly heterogeneous porous media.

  20. In situ sensing of volatile organic compounds in groundwater: first field tests of a mid-infrared fiber-optic sensing system.

    PubMed

    Steiner, H; Jakusch, M; Kraft, M; Karlowatz, M; Baumann, T; Niessner, R; Konz, W; Brandenburg, A; Michel, K; Boussard-Plédel, C; Bureau, B; Lucas, J; Reichlin, Y; Katzir, A; Fleischmann, N; Staubmann, K; Allabashi, R; Bayona, J M; Mizaikoff, B

    2003-06-01

    A prototype mid-infrared sensor system for the determination of volatile organic pollutants in groundwater was developed and tested under real-world conditions. The sensor comprises a portable Fourier transform infrared spectrometer, coupled to the sensor head via mid-infrared transparent silver halide fiber-optic cables. A 10 cm unclad middle section of the 6-m-long fiber is coated with ethylene propylene copolymer in order to enrich the analytes within the penetration depth of the evanescent field protruding from the fiber sensor head. A mixture of tetrachloroethylene, dichlorobenzene, diethyl phthalate, and xylene isomers at concentrations in the low ppm region was investigated qualitatively and quantitatively in an artificial aquifer system filled with Munich gravel. This simulated real-world site at a pilot scale enables in situ studies of the sensor response and spreading of the pollutants injected into the system with controlled groundwater flow. The sensor head was immersed into a monitoring well of the aquifer system at a distance of 1 m downstream of the sample inlet and at a depth of 30 cm. Within one hour, the analytes were clearly identified in the fingerprint region of the IR spectrum (1300 to 700 cm(-1)). The results have been validated by head-space gas chromatography, using samples collected during the field measurement. Five out of six analytes could be discriminated simultaneously; for two of the analytes the quantitative results are in agreement with the reference analysis. PMID:14658691

  1. Heterogeneity of chlorinated hydrocarbon sorption properties in a sandy aquifer.

    PubMed

    Zhao, Xianda; Wallace, Roger B; Hyndman, David W; Dybas, Michael J; Voice, Thomas C

    2005-08-01

    Hydraulic conductivity and sorption coefficients for chlorinated hydrocarbons (chloroform, carbon tetrachloride and tetrachloroethylene) were evaluated for 216 sediment samples collected across a 15 m transect and a 21 m depth interval in a contaminated aquifer near Schoolcraft, Michigan. Relationships between hydraulic conductivity, linear sorption partition coefficients, grain size classes, and spatial location were investigated using linear regression analysis and geostatistical techniques. Clear evidence of layering was found in sorption properties, hydraulic conductivity and grain sizes. Conductivity correlated well with grain size, as expected, but sorption varied inversely with grain size, contrary to some previous reports. No significant correlation was found between sorption properties and hydraulic conductivity. This is likely due to the unexpected presence of small amounts of highly sorptive coal-like solids, which dominate the sorption behavior but have little effect on conductivity. The results demonstrate that recent findings regarding the high sorption capacity of coal materials found in soils can exert a controlling influence on contaminant transport. Designers of in situ remediation systems should be cautioned that 1) it is not reasonable to assume that sorption capacity and hydraulic conductivity are related, 2) sorption capacity and hydraulic conductivity are critical measurements for contaminant site characterization and subsequent transport modeling, 3) estimating sorption capacity from organic carbon measurement may lead to greater errors than performing sorption isotherms, and 4) it is more important to characterize vertical heterogeneity rather than horizontal heterogeneity because both sorption and hydraulic conductivity are correlated across longer distances in the horizontal plane. PMID:16040155

  2. DESORPTION BEHAVIOR OF TRICHLOROETHENE AND TETRACHLOROETHENE IN U.S. DEPARTMENT OF ENERGY SAVANNAH RIVER SITE UNCONFINED AQUIFER SEDIMENTS

    SciTech Connect

    Vangelas, K; Robert G. Riley, R; James E. Szecsody, J; A. V. Mitroshkov, A; C. F. Brown, C; Brian02 Looney, B

    2007-01-10

    Sorption is governed by the physico-chemical processes that partition solutes between the aqueous and solid phases in aquifers. For environmental systems, a linear equilibrium relationship between the amount of contaminant in the alternative phases is often assumed. In this traditional approach, the distribution coefficient, or K{sub d}, is a ratio of contaminant associated with the solid phase to the contaminant in the water phase. Recent scientific literature has documented time-dependant behaviors in which more contaminant mass is held in the solid phase than predicted by the standard model. Depending on the specific conceptualization, this has been referred to as nonlinear sorption, time-variable sorption, or ''irreversible sorption''. The potential impact of time-variable sorption may be beneficial or detrimental depending on the specific conditions and remediation goals. Researchers at the Pacific Northwest National Laboratory (PNNL) have been studying this process to evaluate how various soil types will affect this process for sites contaminated with chlorinated solvents. The results described in this report evaluate sorption-desorption of trichloroethylene (TCE) and tetrachloroethylene (PCE) in Savannah River Site (SRS) soils. The results of this study will be combined with ongoing PNNL research to provide a more comprehensive look at this process and its impact on contaminant plume stability and sustainability. Importantly, while the results of the study documented differences in sorption properties between two tested SRS soils, the data indicated that ''irreversible sorption'' is not influencing the sorption-desorption behaviors of TCE and PCE for these soils.

  3. Membrane-Extraction Ion Mobility Spectrometry for In-Situ Detection of Chlorinated Hydrocarbons in Water

    SciTech Connect

    Du, Yongzhai [ORNL; Zhang, Wei [ORNL; Whitten, William B [ORNL; Li, Haiyang [ORNL; Watson, David B [ORNL; Xu, Jun [ORNL

    2010-01-01

    Membrane-extraction ion mobility spectrometry (ME-IMS) has been developed for in-situ sampling and analysis of trace chlorinated hydrocarbons in water in a single procedure. The sampling is configured so that aqueous contaminants permeate through a spiral hollow polydimethylsiloxane (PDMS) membrane and are carried away by a vapor flow through the membrane tube. The extracted analyte flows into an atmospheric pressure chemical ionization (APCI) chamber and is analyzed in a home-made IMS analyzer. PDMS membrane is found to effectively extract chlorinated hydrocarbon solvents from liquid phase to vapor. The specialized IMS analyzer has been found to have resolutions of R=33 and 41, respectively, for negative- and positive-modes and is capable of detecting aqueous tetrachloroethylene (PCE) and trichloroethylene (TCE) as low as 80 g/L and 74 g/L in negative ion mode, respectively. The time-dependent characteristics of sampling and detection of TCE are both experimentally and theoretically studied for various concentrations, membrane lengths, and flow rates. These characteristics demonstrate that membrane-extraction IMS is feasible for the continuous monitoring of chlorinated hydrocarbons in water.

  4. Review of analytical results from the proposed agent disposal facility site, Aberdeen Proving Ground

    SciTech Connect

    Brubaker, K.L.; Reed, L.L.; Myers, S.W.; Shepard, L.T.; Sydelko, T.G.

    1997-09-01

    Argonne National Laboratory reviewed the analytical results from 57 composite soil samples collected in the Bush River area of Aberdeen Proving Ground, Maryland. A suite of 16 analytical tests involving 11 different SW-846 methods was used to detect a wide range of organic and inorganic contaminants. One method (BTEX) was considered redundant, and two {open_quotes}single-number{close_quotes} methods (TPH and TOX) were found to lack the required specificity to yield unambiguous results, especially in a preliminary investigation. Volatile analytes detected at the site include 1, 1,2,2-tetrachloroethane, trichloroethylene, and tetrachloroethylene, all of which probably represent residual site contamination from past activities. Other volatile analytes detected include toluene, tridecane, methylene chloride, and trichlorofluoromethane. These compounds are probably not associated with site contamination but likely represent cross-contamination or, in the case of tridecane, a naturally occurring material. Semivolatile analytes detected include three different phthalates and low part-per-billion amounts of the pesticide DDT and its degradation product DDE. The pesticide could represent residual site contamination from past activities, and the phthalates are likely due, in part, to cross-contamination during sample handling. A number of high-molecular-weight hydrocarbons and hydrocarbon derivatives were detected and were probably naturally occurring compounds. 4 refs., 1 fig., 8 tabs.

  5. Neurologic illness associated with occupational exposure to the solvent 1-bromopropane--New Jersey and Pennsylvania, 2007-2008.

    PubMed

    2008-12-01

    1-Bromopropane (1-BP) (n-propyl bromide) is a solvent increasingly used as a substitute for ozone-depleting chloro-fluorocarbons and similar regulated compounds. 1-BP is used in vapor and immersion degreasing operations and other manufacturing processes, and as a solvent in industries using aerosol-applied adhesives. In some states, 1-BP is used as a solvent in dry cleaning because of restrictions on use of perchloroethylene (tetrachloroethylene), a possible human carcinogen. Published studies of workers exposed to 1-BP have raised concerns about occupational health risks associated with exposure. This report describes two cases involving workers exposed to 1-BP and diagnosed with clinical manifestations of neurotoxicity. The cases, when coupled with previously reported studies of workers exposed to 1-BP, illustrate potential health risks of 1-BP exposure. Clinicians and public health professionals should be alert to potential health effects among workers exposed to 1-BP, particularly in dry cleaning and other workplaces where 1-BP use might be increasing, and effective control methods to limit exposure to 1-BP should be implemented at worksites. PMID:19052528

  6. Biooxidation studies of pollutants in effluent from the X-710 laboratory

    SciTech Connect

    Greiner, M.J.; Deacon, L.E.

    1983-09-30

    The effluent from the X-710 Laboratory Facility was processed through the original sewage treatment plant with no observable problems. It is now processed through the new treatment plant but this may not satisfy EPA requirements because of possible detrimental effects on the biomass resulting from the presence of toxic pollutants in the X-710 waste stream. As determined by extensive analytical characterization, nine heavy metals and five organics were present in possible environmentally unacceptable concentrations. These were arsenic, cadmium, chromium, copper, iron, nickel, lead, uranium, zinc, acetone, Freon-113, isopropyl alcohol, tetrachloroethylene, and trichloroethylene. The metals and organics were tested to determine their effect on the biomass by biooxidation studies that simulated the activated sludge treatment process in the laboratory. One study tested the metals for a two-month period, while another study tested the organics for a two-month period. In both cases, the maximum contaminant concentrations observed were used in the tests to ensure worst possible case conditions for study. Results of both studies indicated that no detrimental effect was seen on the biomass at the concentrations tested. Thus, no further testing or investigation of pretreatment technologies for the X-710 effluent was required since the laboratory studies show that effluents can be processed through the X-6619 Sewage Treatment Facility with no toxic effect on the biomass. 2 refs., 2 figs.

  7. Savannah River Site A/M Area Southern Sector Characterization Cone Penetrometer Report

    SciTech Connect

    Raabe, B.A. [Westinghouse Savannah River Company, Aiken, SC (United States)

    1993-05-01

    The Savannah River Site (SRS) is located in the Atlantic Coastal Plaingeologic province. This area is characterized by low relief, predominantly unconsolidated sediments of Cretaceous though Tertiary age. A multiple aquifer system underlies the A/M Area and affects the definition and distribution of a contaminant plume. The water table and uppermost confined aquifer (Steed Pond Aquifer) are contaminated with elevated concentrations of trichloroethylene(TCE) and tetrachloroethylene (PCE) and their associated compounds. The deeper aquifers in this area have less widely spread chlorinated hydrocarbon contamination.Cone penetrometer testing was selected as the method of investigation because it is minimally invasive, offers advanced technological capabilities in gathering lithologic data, and offers groundwater sampling capabilities. CPT testing utilizes a hydraulic push tool system. The probe collects real-time data that is processed by computer into soil/lithology classifications. The system can also be used to collect sediment and soil vapor samples although these features were not utilized during this project. Advantages of the CPT system include a small borehole diameter which minimizes cross-contamination of lithologic units, virtual elimination of drill cuttings and fluids that require disposal, collection of various types of undisturbed sediment and water samples and plotting of hydrostratigraphic and lithologic data while in the field.

  8. Preliminary Engineering Report contaminated groundwater seeps 317/319/ENE area

    SciTech Connect

    NONE

    1996-10-01

    When the Resource Conservation and Recovery Act Facility Investigation (RFI) in the 317/319/ENE Area of Argonne National Laboratory-East (ANL-E) was being completed, groundwater was discovered moving to the surface through a series of seeps. The seeps are located approximately 600 ft south of the ANL fence line in Waterfall Glen Forest Preserve. Samples of this water were collected and analyzed for selected parameters. Two of five seeps sampled were found to contain detectable levels of organic contaminants. Three chemical species were identified: chloroform (14-25 {mu}g/L), carbon tetrachloride (56-340 {mu}g/L), and tetrachloroethylene (3-6 {mu}g/L). The other seeps did not contain detectable levels of volatile organic compounds (VOCs). The water issuing from these two contaminated seeps flows into a narrow ravine, where it is visible as a trickle of water flowing through sand and gravel deposits on the floor of the ravine. Approximately 100-ft downstream of the seep area, the contaminated water is no longer visible, having drained back into the soil in the bed of the ravine. Figure 1 shows the location of the 317/319/ENE Area in relation to the ANL-E site and the Waterfall Glen Forest Preserve.

  9. Inspection and monitoring plan, contaminated groundwater seeps 317/319/ENE Area, Argonne National Laboratory

    SciTech Connect

    NONE

    1996-10-11

    During the course of completing the Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) in the 317/319/East-Northeast (ENE) Area of Argonne National Laboratory-East (ANL-E), groundwater was discovered moving to the surface through a series of groundwater seeps. The seeps are located in a ravine approximately 600 ft south of the ANL-E fence line in Waterfall Glen Forest Preserve. Samples of the seep water were collected and analyzed for selected parameters. Two of the five seeps sampled were found to contain detectable levels of organic contaminants. Three chemical species were identified: chloroform (14--25 {micro}g/L), carbon tetrachloride (56--340 {micro}g/L), and tetrachloroethylene (3--6 {micro}g/L). The other seeps did not contain detectable levels of volatile organics. The nature of the contaminants in the seeps will also be monitored on a regular basis. Samples of surface water flowing through the bottom of the ravine and groundwater emanating from the seeps will be collected and analyzed for chemical and radioactive constituents. The results of the routine sampling will be compared with the concentrations used in the risk assessment. If the concentrations exceed those used in the risk assessment, the risk calculations will be revised by using the higher numbers. This revised analysis will determine if additional actions are warranted.

  10. Henry's law constants of chlorinated solvents at elevated temperatures.

    PubMed

    Chen, Fei; Freedman, David L; Falta, Ronald W; Murdoch, Lawrence C

    2012-01-01

    Henry's law constants for 12 chlorinated volatile organic compounds (CVOCs) were measured as a function of temperature ranging from 8 to 93°C, using the modified equilibrium partitioning in closed system (EPICS) method. The chlorinated compounds include tetrachloroethylene, trichloroethylene, cis-1,2-dichloroethylene, vinyl chloride, 1,1,1-trichloroethane, 1,1-dichloroethane, 1,2-dichloroethane, chloroethane, carbon tetrachloride, chloroform, dichloromethane, and chloromethane. The variation in Henry's constants for these compounds as a function of temperature ranged from around 3-fold (chloroethane) to 30-fold (1,2-dichloroethane). Aqueous solubilities of the pure compounds were measured over the temperature range of 8-75°C. The temperature dependence of Henry's constant was predicted using the ratio of pure vapor pressure to aqueous solubility, both of which are functions of temperature. The calculated Henry's constants are in a reasonable agreement with the measured results. With the improved data on Henry's law constants at high temperatures measured in this study, it will be possible to more accurately model subsurface remediation processes that operate near the boiling point of water. PMID:22071373

  11. Synthesis of nanoporous Al2O3 membranes from polybutyl methacrylate functionalized SiO2 particles as a sacrificial template.

    PubMed

    Tseng, Wenjea J; Guo, Shiuan-Fu

    2012-10-01

    SiO2 surface is first modified with 3-trimethoxysilyl propyl methacrylate (MPS) in order to graft with polymerized butyl methacrylate (BMA) to form SiO2@MPS-BMA core--shell hybrid particles. The polymeric BMA shell enables anchoring of aluminum ions in tetrachloroethylene solvent, results in SiO2 @Al2O3 composite particles upon subjected to calcination. Removal of the SiO2 core by acid etching forms nanoporous gamma-Al2O3 membrane with a Horvath-Kawazoe (HK) pore size of 1.4 nm and a Brunauer-Emmett-Teller (BET) surface area of 78.6 m2 x g(-1). Transmission electron microscopy reveals formation of interconnected pore channels in the membrane. It is interesting to note that the Al2O3 membrane remains at a reasonably high surface area (53.9 m2 x g(-1)) after an isothermal holding at 1200 degrees C, when gamma-Al2O3 changed into predominately alpha-Al2O3. The process is indeed general and can be extended to the synthesis of other inorganic porous solids. PMID:23421155

  12. Synergistic and antagonistic effects on genotoxicity of chemicals commonly found in hazardous waste sites

    SciTech Connect

    Ma, T.H.; Sandhu, S.S.; Peng, Y.; Chen, T.D.; Kim, T.W.

    1992-01-01

    Synergistic and antagonistic effects on genotoxicity of mixtures of four chemicals; i.e., lead tetraacetate (LTA), arsenic trioxide (ATO), dieldrin (DED), and tetrachloroethylene (TCE), were evaluated by the Tradescantia-micronucleus (Trad-MCN) assay. The chemicals were mixed in ratios of 1:1, 1:2 and 2:1 for mixtures of two chemicals and 1:1:1 each for three chemicals. The concentration of stock solution of these chemicals was around the minimum effective dose (MED) or below the MED for these chemicals as reported by Sandhu et al. (1989). Treatments were applied to plant cuttings by hydroponic uptake of the mixed solutions through the stems of the plant for 30 h followed by fixation of the flower buds in aceto-alcohol (1:3 ratio) without a recovery period. Microslides were prepared for scoring MCN frequencies. Results of two series of repeated experiments indicated that all mixtures of LTA/ATO exhibited antagonistic effects. On the other hand, all mixtures of TCE and DED exhibited synergistic effect. These data indicate that for evaluating biological hazards at chemical waste sites, it is prudent to evaluate the genotoxicity of complex chemical mixtures as these exist in nature because the biological effects based on evaluating individual chemicals may not be true predictors of the interactive effects of the pollutants.

  13. Sorption of vapors of some organic liquids on soil humic acid and its relation to partitioning of organic compounds in soil organic matter

    USGS Publications Warehouse

    Chlou, G.T.; Kile, D.E.; Malcolm, R.L.

    1988-01-01

    Vapor sorption of water, ethanol, benzene, hexane, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and 1,2-dibromoethane on (Sanhedron) soil humic acid has been determined at room temperature. Isotherms for all organic liquids are highly linear over a wide range of relative pressure (P/P??), characteristic of the partitioning (dissolution) of the organic compounds in soil humic acid. Polar liquids exhibit markedly greater sorption capacities on soil humic acid than relatively nonpolar liquids, in keeping with the polar nature of the soil humic acid as a partition medium. The limiting sorption (partition) capacities of relatively non-polar liquids are remarkably similar when expressed in terms of volumes per unit weight of soil humic acid. The soil humic acid is found to be about half as effective as soil organic matter in sorption of relatively nonpolar organic compounds. The nearly constant limiting sorption capacity for nonpolar organic liquids with soil humic acid on a volume-to-weight basis and its efficiency in sorption relative to soil organic matter provide a basis for predicting the approximate sorption (partition) coefficients of similar compounds in uptake by soil in aqueous systems.

  14. Haloalkene oxidation by the soluble methane monooxygenase from Methylosinus trichosporium OB3b: mechanistic and environmental implications.

    PubMed

    Fox, B G; Borneman, J G; Wackett, L P; Lipscomb, J D

    1990-07-10

    The soluble, three-protein component methane monooxygenase purified from Methylosinus trichosporium OB3b is capable of oxidizing chlorinated, fluorinated, and brominated alkenes, including the widely distributed ground-water contaminant trichloroethylene (TCE). The oxidation rates for the chloroalkenes were observed to be comparable to that for methane, the natural substrate, and up to 7000-fold higher than those reported for other well-defined biological systems. The competitive inhibitor tetrachloroethylene was found to be the only chlorinated ethylene not turned over. However, this appears to be due to steric effects rather than electronic effects or the lack of an abstractable proton because chlorotrifluoroethylene was efficiently oxidized. As evidenced by the formation of diagnostic adducts with 4-(p-nitrobenzyl)pyridine, the halogenated alkenes were oxidized predominantly by epoxidation. Stable acidic products resulting from subsequent hydrolysis were identified as the major products. However, additional aldehydic products resulting from intramolecular halide or hydride migration were observed in 3-10% yield during the oxidation of TCE, vinylidene chloride, trifluorethylene, and tribromoethylene. Product analysis of the hydrolysis reaction of authentic TCE epoxide showed little or no 2,2,2-trichloroacetaldehyde (chloral) formation, indicating that atomic migration occurred prior to product dissociation from the enzyme. The occurrence of atomic migration products shows that an intermediate in the substrate to product conversion carries significant cationic character. Such a species could be generated through interaction with a highly electron-deficient activated oxygen in the active site.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2207083

  15. FIELD SCREENING FOR HALOGENATED VOLATILE ORGANIC COMPOUNDS

    SciTech Connect

    John F. Schabron; Joseph F. Rovani Jr.; Theresa M. Bomstad

    2002-06-01

    Western Research Institute (WRI) initiated exploratory work towards the development of new field screening methodology and a test kit to measure halogenated volatile organic compounds (VOCs) in the field. Heated diode and corona discharge sensors are commonly used to detect leaks of refrigerants from air conditioners, freezers, and refrigerators. They are both selective to the presence of carbon-halogen bonds. Commercially available heated diode and corona discharge leak detectors were procured and evaluated for halogenated VOC response. The units were modified to provide a digital readout of signal related to VOC concentration. Sensor response was evaluated with carbon tetrachloride and tetrachloroethylene (perchloroethylene, PCE), which represent halogenated VOCs with and without double bonds. The response characteristics were determined for the VOCs directly in headspace in Tedlar bag containers. Quantitation limits in air were estimated. Potential interferences from volatile hydrocarbons, such as toluene and heptane, were evaluated. The effect of humidity was studied also. The performance of the new devices was evaluated in the laboratory by spiking soil samples and monitoring headspace for halogenated VOCs. A draft concept of the steps for a new analytical method was outlined. The results of the first year effort show that both devices show potential utility for future analytical method development work towards the goal of developing a portable test kit for screening halogenated VOCs in the field.

  16. A pilot study for delineation of areas contributing water to wellfields at Jackson, Tennessee

    USGS Publications Warehouse

    Broshears, R.E.; Connell, J.F.; Short, N.C.

    1991-01-01

    The U.S. Geological Survey, in cooperation with the Tennessee Department of Health and Environment, Division of Groundwater Protection, and the Jackson Utility Division, conducted a pilot study to determine data needs and the applicability of four methods for the delineation of wellhead protection areas. Jackson Utility Division in Jackson, Madison County, Tennessee, pumps about 9 million gallons of ground water daily from two municipal wellfields that tap an unconfined sand aquifer. Under natural hydraulic gradients, ground waterflows southward toward the South Wellfield at approximately 2 to 3 feet per day; natural flow toward the North Wellfield from the east at 1 to 2 feet per day. Water quality generally is suitable for most uses. Concentrations of dissolved solids are low, and excessive iron is the only significant naturally occurring water-quality problem. However, trace concentrations of volatile organic compounds have been detected in water pumps from the South Wellfield; the highest concentration of a single compound has been 23 micrograms per liter of tetrachloroethylene. Potential sources of ground-water contamination in the Jackson area include a hazardous-waste site, municipal and industrial landfill, and underground-storage tanks. Some of the four method for delineating wellhead protection areas did not adequately describe zones contributing flow to the wellfields. Calculations based on a uniform flow equation provided a preliminary delineation of zones of contribution for the wellfields and ground-water time-of-travel contours. Limitations of the applied methods motivated the design of a more rigorous hydrogeologic investigation.

  17. Carbonaceous sorbents for high-temperature interactive liquid chromatography of polyolefins.

    PubMed

    Chitta, Rajesh; Macko, Tibor; Brüll, Robert; Miller, Matthew; Cong, Rongjuan; deGroot, Willem

    2013-07-01

    The elution behavior of polyethylene (PE) and the three stereoisomers of polypropylene (PP) was studied on porous graphite along with three other carbon-based sorbents, carbon-clad zirconia particles, activated carbon, and exfoliated graphite in a systematic way in this work. Decahydronaphthalene, 1,2,3,4-tetrahydronaphthalene, 1,3,5-trimethylbenzene, tetrachloroethylene, xylene and p-xylene were used as mobile phases. While PE is adsorbed to various extents on all the tested carbonaceous sorbents from the majority of the solvents, PP is fully adsorbed only in selected cases. Testing alcohols (C7-C9) as mobile phase with Hypercarb™ indicates that all stereoisomers of PP are selectively adsorbed and desorbed when a solvent gradient alcohol?1,2,4-trichlorobenzene is used at 160°C. The retention of all stereoisomers of PP increases with the polarity of the alcohol. Linear PE is retained on Hypercarb™ even from 1,2-dichloro- and 1,2,4-trichlorobenzene, when a temperature below 120°C is applied, while it is not retained from these solvents at higher temperatures. All stereoisomeric forms of PP are not adsorbed under the same conditions. Some of the tested new sorbent/solvent systems have potential to be applied in routine analysis of industrially synthesised polyolefins. PMID:23616412

  18. Identification of reaction intermediates/products from the photocatalytic degradation of trichloroethylene on illuminated titanium dioxide surfaces

    SciTech Connect

    Hung, C.H.; Marinas, B.J. [Purdue Univ., West Lafayette, IN (United States)

    1996-11-01

    The objective of this study was to identify reaction intermediates/products from the gas-phase photocatalytic degradation of trichloroethylene (TCE) on anatase titanium dioxide (TiO{sub 2}) surfaces illuminated with near-ultraviolet light (360 nm wavelength). A Pyrex glass annular photocatalytic reactor fabricated with turbulence promoters was used for this purpose. The inner surface of the outside tube forming the annular reactor was coated with TiO{sub 2} prepared by vapor phase hydrolysis of titanium isopropoxide. Reaction intermediates/products were concentrated by passing the photocatalytic reactor off-gas through a stainless steel tube immersed in liquid nitrogen. Compounds deposited were allowed to revolatilize or were washed with deionized water and analyzed by gas chromatography with a mass spectrum selective detector (GC/MS), or by ion chromatography (IC), respectively. Preliminary results revealed the presence of many halogenated organic compounds, including phosgene, 1,2-dichloroethylene, chloroform, carbon tetrachloride, dichloroacetyl chloride, 1,1,2-trichloroethane, tetrachloroethylene, 1,1,2,2-tetrachloroethane, pentchloroethane, and hexachloroethane, as well as hydrochloric acid. The abundance of most of these compounds except phosgene and hydrochloric acid was observed to diminish with increasing oxygen concentrations. Possible reaction mechanisms and pathways for the photocatalytic degradation of TCE will be presented.

  19. Calculation of relative Raman intensities. I. Influence of CNDO/2 and LNDO parameters on the calculated intensities

    NASA Astrophysics Data System (ADS)

    Wiegeler, W.; Bleckmann, P.

    1980-08-01

    Line intensities in Raman spectra are determined by means of a modified CNDO/2 and a modified INDO method [1, 2]. Perturbation terms are developed which are inserted into the Hartree—Fock operator used in the CNDO/2 and INDO theory [3, 4] to yield the induced dipole moment as a function of the normal co-ordinate Q, from which the polarizability change upon Q is obtained. The normal co-ordinate determination is carried out with a program developed by us [5]. The influence of different basis sets on the calculated Raman intensities of phosgene, dichloromethane, tetrachloroethylene, cis-1,2-dichloroethylene and on the thiocyanate anion, all of which contain second-row elements, is investigated. We obtain the best correlation between theoretical and observed intensities if the number of basis functions is the same for each atom in a molecule. For the intensity calculation on formaldehyde, we have used the energy minimum geometries. Contrary to expectation, they do not lead to better intensities than calculations using experimental structural data. It is shown that the description of hydrogen atoms by only one 1 s function is insufficient for the calculation of relative Raman intensities by the CNDO/2 and the INDO method.

  20. Identification and quantification of products formed from the photocatalytic degradation of trichloroethylene vapor on TlO{sub 2} illuminated with near-UV light

    SciTech Connect

    Hung, C.H.; Marinas, B.J. [Purdue Univ., West Lafayette, IN (United States)

    1995-12-31

    The objectives of this study were to identify and quantify reaction products from photocatalytic degradation of trichloroethylene (TCE) vapor on the surfaces of anatase titanium dioxide (TiO{sub 2}) immobilized inside a reactor with annular configuration at ambient temperature and pressure. Ten chlorinated organic compounds including phosgene (COCl{sub 2}), 1,2-dichloroethylene (C{sub 2}H{sub 2}Cl{sub 2}), dichloroacetyl chloride (C{sub 2}HCl{sub 3}O), chloroform (CHCl{sub 3}), carbon tetrachloride (CCl{sub 4}), 1,1,2-trichloroethane (C{sub 2}H{sub 3}Cl{sub 3}), 1,1,2,2-tetrachloroethane (C{sub 2}H{sub 2}Cl{sub 4}), tetrachloroethylene (C{sub 2}O{sub 4}), pentachloroethane (C{sub 2}HCl{sub 5}), and hexachloroethane (C{sub 2}Cl{sub 4}) and two inorganic specks HCl and Cl{sub 2} were identified in the photocatalytic reactor effluent. In general, the fraction of TCE going into chlorinated organic products appeared to peak at an oxygen concentration of 150 ppmv and then to decrease at higher oxygen levels. Cl-containing products observed at high oxygen concentrations were predominately the inorganic species HCl and Cl{sub 2}.

  1. A paired comparison between human skin and hairless guinea pig skin in vitro permeability and lag time measurements for 6 industrial chemicals.

    PubMed

    Frasch, H Frederick; Barbero, Ana M

    2009-01-01

    The purpose of the present study was to measure and compare permeability coefficients (k(p)) and lag times (tau) in human skin and hairless guinea pig (HGP) skin. Paired experiments employed heat-separated epidermal membranes from human and HGP sources mounted on static in vitro diffusion cells. Infinite-dose, saturated aqueous solutions of 6 industrial chemicals were used as donors: aniline, benzene, 1,2- dichloroethane, diethyl phthalate, naphthalene, and tetrachloroethylene. No significant differences were found between human and HGP skin for either k(p) or tau for any of these chemicals (p >or= .24). HGP vs. human k(p) measurements, and HGP vs. human tau measurements, were highly correlated. For k(p), the slope of the linear correlation was close to unity (1.080 +/- 0.182) and the intercept close to 0 (0.015 +/- 0. 029 cm/h), with a correlation coefficient (r(2)) = 0.898. For tau, the slope was also close to unity (0.818 +/- 0.030) and the intercept close to 0 (-0.014 +/- 0.023 h), with r(2) = 0.994. These results suggest that HGP skin may serve as an excellent surrogate for human skin in in vitro dermal penetration studies. PMID:19552540

  2. 1992 toxic hazards research unit annual report. Annual report, 1 October 1991-30 September 1992

    SciTech Connect

    Wall, H.G.; Dodd, D.E.; Vinegar, A.; Schneider, M.G.

    1993-04-01

    This report presents a review of the activities of the Toxic Hazards Research Unit (THRU) for the period 1 October 1991 through 30 September 1992. The THRU conducts descriptive, mechanistic, and predictive toxicology research and toxicological risk assessments to provide data to predict health hazards and to assess health risks associated with human exposure to chemicals and materials associated with military systems and operational environments. The report includes summaries of ongoing or completed research activities for the individual toxicology research requirements of the U.S. Air Force, Army, and Navy; highlights of the research support elements and conference activities of the THRU; and appendices that describe the THRU organization and its publications and presentations. 1,3,3-Trinitroazetidine (TNAZ), 1,3,5-Trinitrobenzene (TNB), Carboxylic acid metabolite, Chlorofluorocarbon, Chloroform, Delayed neurotoxicity, Halon replacement, Hydraulic fluid, Hydrazine, Inhalation, Jet engine oil, Lactational transfer, Methylene chloride, MIL-H-19457C, Neurotoxic Esterase (NTE), OTTO Fuel II, Perchloroethylene (PCE), Physiologically Based Pharmacokinetic (PBPK) modeling, Polychlorotrifluoroethylene (pCTFE), Quantitative Structure-Activity Relationships (QSAR), Reproductive, Risk assessment, Smoke, Tetrachloroethylene (PCE), Toxic dust, Vinyl Chloride (VC) and Trichloroethylene (TCE) mixture.

  3. Occupational exposure to rubber vulcanization products during repair of rubber conveyor belts in a brown coal mine.

    PubMed

    Gromiec, Jan P; Weso?owski, Wiktor; Brze?nicki, S?awomir; Wróblewska-Jakubowska, Krystyna; Kucharska, Ma?gorzata

    2002-12-01

    Several hundred chemical compounds were found in workroom environments in the rubber industry, but most of the published exposure data relate to the production of tyres; information from the "non-tyre" sections are very limited, if any. This study was carried out to identify chemical substances and measure their air concentrations in the repair shop of a brown coal mine in which damaged rubber conveyor belts were repaired. GC-MS and HPLC analysis of stationary air samples resulted in identification of aliphatic and aromatic hydrocarbons to C12, PAHs, alcohols, phenols, ketones, heterocyclic nitrogen and sulfur compounds. Quantitative evaluation of occupational exposure included determination of organic compound vapours collected on charcoal (GC-MSD), polycyclic aromatic hydrocarbons (HPLC), N-nitrosoamines and other amines (GC-NPD) and DNPH derivatives of aldehydes (HPLC) in the breathing zone of workers representing all job titles. The concentrations of investigated compounds were very low. Carcinogenic substances: N-nitrosoamines, benzene, PAHs were not present in workroom air in concentrations exceeding limits of detection of the analytical methods being applied; concentrations of methylisobutylketone, tetrachloroethylene, naphtha, aromatic hydrocarbons, phthalates and aldehydes were much lower than the respective occupational exposure limit values. The results indicate much lower exposure than that reported in the production of tyres and other fabricated rubber products. PMID:12509065

  4. Analysis of nitrate and volatile organic compound data for ground water in the Great Salt Lake Basins, Utah, Idaho, and Wyoming, 1980-98, National Water-Quality Assessment Program

    USGS Publications Warehouse

    Thiros, Susan A.

    2000-01-01

    In 1995, ground water was the source of drinking water to about 52 percent of the population served by public drinking water systems in the Great Salt Lake Basins study unit, which includes parts of Utah, Idaho, and Wyoming. Existing nitrate and volatile organic compound data for ground water collected in the study unit were compiled and summarized as part of the National Water-Quality Assessment Program?s objective to describe water-quality conditions in the Nation?s aquifers. Prerequisites for the inclusion of nitrate and volatile organic compound data into this retrospective analysis are that the data set is available in electronic form, the data were collected during 1980-98, the data set is somewhat regional in coverage, and the locations of the sampled sites are known. Ground-water data stored in the U.S. Geological Survey?s National Water Information Systemand the Idaho and Utah Public DrinkingWater Systems databases were reviewed. Only the most recent analysis was included in the data sets if more than one analysis was available for a site. The National Water Information System data set contained nitrate analyses for water from 480 wells. The median concentration of nitratewas 1.30 milligrams per liter for the 388 values above minimum reporting limits. The maximum contaminant level for nitrate as established by the U.S. Environmental Protection Agency was exceeded in water from 10 of the 200 wells less than or equal to 150 feet deep and in water from3 of 280 wells greater than 150 feet deep. The Public Drinking Water Systems data set contained nitrate analyses for water from 587 wells. The median concentration of nitrate was 1.12 milligrams per liter for the 548 values above minimum reporting limits. The maximum contaminant level for nitrate was exceeded at 1 site and 22 sites had concentrations equal to or greater than 5 milligrams per liter. The types of land use surrounding a well and the well depth were related to measured nitrate concentrations in the sampled ground water. Overall, water sampled from wells in rangeland areas had a lowermedianmeasured nitrate concentration (0.76 milligrams per liter) than water from areas with an agricultural or urban/residential land use (1.41 and 1.20 milligrams per liter, respectively). In the NationalWater Information System data set, the median measured nitrate concentration in water from urban/residential areas varied from 1.00 milligrams per liter for wells greater than 150 feet deep to 1.84 milligrams per liter for wells less than or equal to 150 feet deep. The Public DrinkingWater Systems and the National Water Information System data sets contained analyses for most of the State and Federally regulated volatile organic compounds in water from about 368 and 74 wells, respectively. Fifteen different volatile organic compounds were detected at least once in ground water sampled from the Great Salt Lake Basins study unit. Water from 21 wells contained at least 1 volatile organiccompound at detectable concentrations. About 68 percent of the volatile organic compounds detected were in water sampled from wells in Salt Lake County, Utah. Tetrachloroethylene was the most commonly detected volatile organic compound in ground water sampled from the study unit, present in 8 out of 442 samples. Maximum contaminant levels for tetrachloroethylene and 1,1-dichloroethylene as established by the U.S. Environmental Protection Agency were exceeded in water from one well each.

  5. Occurrence of Selected Organic Compounds in Groundwater Used for Public Supply in the Plio-Pleistocene Deposits in East-Central Nebraska and the Dawson and Denver Aquifers near Denver, Colorado, 2002-2004

    USGS Publications Warehouse

    Bails, Jeffrey B.; Dietsch, Benjamin J.; Landon, Matthew K.; Paschke, Suzanne S.

    2009-01-01

    The National Water-Quality Assessment Program of the U.S. Geological Survey has an ongoing Source Water-Quality Assessment program designed to characterize the quality of water in aquifers used as a source of drinking-water supply for some of the largest metropolitan areas in the Nation. In addition to the sampling of the source waters, sampling of finished or treated waters was done in the second year of local studies to evaluate if the organic compounds detected in the source waters also were present in the water supplied to the public. An evaluation of source-water quality used in selected groundwater-supplied public water systems in east-central Nebraska and in the south Denver metropolitan area of Colorado was completed during 2002 through 2004. Fifteen wells in the Plio-Pleistocene alluvial and glacial deposits in east-central Nebraska (the High Plains study) and 12 wells in the Dawson and Denver aquifers, south of Denver (the South Platte study), were sampled during the first year to obtain information on the occurrence and distribution of selected organic chemicals in the source waters. During the second year of the study, two wells in east-central Nebraska were resampled, along with the associated finished water derived from these wells, to determine if organic compounds detected in the source water also were present in the finished water. Selection of the second-phase sampling sites was based on detections of the most-frequently occurring organic compounds from the first-year Source Water-Quality Assessment study results. The second-year sampling also required that finished waters had undergone water-quality treatment processes before being distributed to the public. Sample results from the first year of sampling groundwater wells in east-central Nebraska show that the most-frequently detected organic compounds were the pesticide atrazine and its degradate, deethylatrazine (DEA, otherwise known as 2-chloro-4-isopropylamino-6-amino-s-triazine or CIAT), which were detected in 9 of the 15 wells (60 percent of the samples). The second most frequently detected organic compound was tetrachloroethylene, detected in 4 of the 15 wells (27 percent of the samples), followed by chloroform, trichloroethylene, and 2-hydroxyatrazine (2-hydroxy-4-isopropylamino-6-ethylamino-s-triazine, or OIET), present in 3 of the 15 wells (20 percent of the samples). The pesticide compounds deisopropylatrazine (2-chloro-6-ethylamino-4-amino-s-triazine, or CEAT), metolachlor, and simazine and the volatile organic compound cis-1,2-dichloroethylene were detected in 2 of the 15 wells, and the compounds diuron and 1,2-dichloroethane were detected in only 1 of the 15 wells during the first-year sampling. Most detections of these compounds were at or near the minimum reporting levels, and none were greater than their regulatory maximum contaminant level. There were few detections of organic compounds during the first year of sampling groundwater wells in the South Platte study area. The compounds atrazine, deethylatrazine, picloram, tetrachloroethylene, methyl-tert-butyl-ether (MTBE), tris(2-butoxyethyl)phosphate, and bromoform were detected only once in all the samples from the 12 wells. Most detections of these compounds were at or near the minimum reporting levels, and none were greater than their regulatory maximum contaminant level. Second-year sampling, which included the addition of paired source- and finished-water samples, was completed at two sites in the High Plains study area. Source-water samples from the second-year sampling had detections of atrazine and deethylatrazine; at one site deisopropylatrazine and chloroform also were detected. The finished-water samples, which represent the source water after blending with water from other wells and treatment, indicated a decrease in the concentrations of the pesticides at one site, whereas concentrations remained nearly constant at a second site. The trihalomethanes (THMs or disinfec

  6. Effect of Clay on DNAPL Mobilization During Alcohol Flushing

    NASA Astrophysics Data System (ADS)

    Rossman, A. J.; Hayden, N. J.; Matmon, D.

    2001-05-01

    An improved understanding of dense non-aqueous phase liquid (DNAPL) behavior in clay-containing porous media is critical for improving restoration attempts using in-situ remediation techniques such as alcohol flushing. Clay type and clay fraction at the pore scale affect initial DNAPL distribution and potential mobilization during alcohol flushing. Mobilization experiments were performed on columns containing well-sorted Ottawa white sand and columns containing sand with a 10 percent clay fraction. The clays used were Kaolinite and Ca-montmorillonite. The columns were characterized for pore-size distribution using pressure-saturation experiments and brought to a residual tetrachloroethylene (PCE) saturation before flushing. Successive increments of isopropyl alcohol (IPA) were flushed through the columns to determine the alcohol concentration at the onset of mobilization. In columns containing pure sand and 10 percent Kaolinite (K10), PCE mobilized at approximately the same IPA concentration. PCE mobilized with a much lower IPA concentration in columns containing 10 percent Ca-montmorillonite (M10) indicating that Ca-montmorillonite is affecting DNAPL mobilization. The mobilization at lower IPA concentrations may be due to differing pore sizes and pore-size distributions resulting from the clay type, clay colloid detachment during flushing, interfacial interactions between clay, DNAPL and the pore fluid or some combination of these factors. Pressure-saturation relationships show smaller pores and a greater pore size distribution in the M10 columns. Colloids were observed in the effluent in many experiments and a statistically significant decrease in PCE/water interfacial tension was measured in solutions containing Ca-montmorillonite colloids.

  7. Effect of Humic Acid on Migration, Distribution and Remediation of Dense Non-aqueous Phase Liquids: A laboratory investigation

    NASA Astrophysics Data System (ADS)

    Cheng, Z.; Wu, J.; Xu, H.; Gao, Y.

    2014-12-01

    Over the last decades, dense non-aqueous phase liquids (DNAPLs) contamination in the subsurface increases with the rapid development of oil industry and becomes the focus of many studies. The migration, distribution and remediation efficiency of DNAPLs in the subsurface environment are greatly affected by the solution chemistry besides the physical heterogeneities of aquifers. Humic acid (HA), which is ubiquitous in natural environments, is a surface active substance exhibiting solubility enhancement behavior for hydrophobic organic compounds such as DNAPLs. Here we reported a laboratory investigation to study the effects of HA on the infiltration, immobilization and subsequent recovery of DNAPL in porous media. Tetrachloroethylene (PCE) was selected as the representative DNAPL in this study. Two-dimensional (2-D) sandbox experiments were conducted to investigate the effects of different HA concentrations on the transport, distribution of PCE and the remediation of PCE using surfactant (Tween 80) flushing in a saturated porous media system. The surfactant flushing of PCE was performed after the PCE transport and distribution had reached equilibrium. A light transmission visualization method with charge-coupled device (CCD) camera was adopted to visualize PCE distribution and quantify its saturation. In addition, the experiments were also designed to gather data for the validation of multiphase flow models. Effluent samples were collected to determine dissolved PCE concentrations. PCE solubilization and PCE-water interfacial tension were experimentally determined in aqueous solutions of varying HA concentrations. The experimental results showed that the presence of HA can have a dramatic impact on PCE flow and entrapment, and significantly improved the recovery of PCE during surfactant enhanced aquifer remediation (SEAR). The findings are of use for better understanding of the migration and entrapment of DNAPLs and developing of SEAR technology.

  8. Radionuclides, metals, and organic compounds in water, eastern part of A and B irrigation district, Minidoka County, Idaho

    SciTech Connect

    Mann, L.J.; Knobel, L.L. (Geological Survey, Idaho Falls, ID (United States))

    1990-01-01

    The US Geological Survey, in response to a US Department of Energy request, collected and analyzed water samples from 15 sites in Minidoka County, Idaho. Samples were collected from 12 groundwater and 3 irrigation wastewater sites. Samples were analyzed for tritium, gross alpha-particle and beta-particle radioactivity, total uranium, radium, radon-222, strontium-90, gross gamma radioactivity, trace metals, purgeable organic compounds, nutrients, and pesticides. Seven samples had tritium concentrations larger than the reporting level, ranging from 0.045 [plus minus]0.013 to 0.106 [plus minus]0.013 pCi/ml. Ranges of dissolved concentrations for some other radionuclides or types of radioactivity follow: gross alpha-particles radioactivity as thorium-230 - 2.23 [plus minus]0.61 to 9.10 [plus minus]1.25 pCiL; gross beta-particle radioactivity as strontium-90 in equilibrium with yttrium-90 - 2.50 [plus minus]1.28 to 10.3 [plus minus]2.5 pCi/L; total uranium - 1.38 [plus]/[minus]0.16 to 5.22 [plus minus]1.02 microg/L; radium-226 - 0.0102 [plus minus]0.0064 to 0.149 [plus minus]0.024 pCi/L; and strontium-90 - from [lt] the reporting level to 0.483 [plus minus]0.071 pCi/L. Concentrations of nitrite plus nitrate as nitrogen ranged from 0.94 to 5 mg/L. Tetrachloroethylene and benzene were present in water from an irrigation drain.

  9. Effects of Daily Precipitation and Evapotranspiration Patterns on Flow and VOC Transport to Groundwater along a Watershed Flow Path

    USGS Publications Warehouse

    Johnson, R.L.; Thoms, R.B.; Zogorski, J.S.

    2003-01-01

    MTBE and other volatile organic compounds (VOCs) are widely observed in shallow groundwater in the United States, especially in urban areas. Previous studies suggest that the atmosphere and/or nonpoint surficial sources could be responsible for some of those VOCs, especially in areas where there is net recharge to groundwater. However, in semiarid locations where annual potential evapotranspiration can exceed annual precipitation, VOC detections in groundwater can be frequent. VOC transport to groundwater under net discharge conditions has not previously been examined. A numerical model is used here to demonstrate that daily precipitation and evapotranspiration (ET) patterns can have a significant effect on recharge to groundwater, water table elevations, and VOC transport. Ten-year precipitation/ET scenarios from six sites in the United States are examined using both actual daily observed values and "average" pulsed precipitation. MTBE and tetrachloroethylene transport, including gas-phase diffusion, are considered. The effects of the precipitation/ET scenarios on net recharge and groundwater flow are significant and complicated, especially under low-precipitation conditions when pulsed precipitation can significantly underestimate transport to groundwater. In addition to precipitation and evapotranspiration effects, location of VOC entry into the subsurface within the watershed is important for transport in groundwater. This is caused by groundwater hydraulics at the watershed scale as well as variations in ET within the watershed. The model results indicate that it is important to consider both daily precipitation/ET patterns and location within the watershed in order to interpret VOC occurrence in groundwater, especially in low-precipitation settings.

  10. Distribution of volatile organic compounds in a New Jersey coastal plain aquifer system

    USGS Publications Warehouse

    Fusillo, T.V.; Hochreiter, J.J., Jr.; Lord, D.G.

    1985-01-01

    Samples for analysis of volatile organic compounds were collected from 315 wells in the Potomac-Raritan-Magothy aquifer system in southwestern New Jersey and a small adjacent area in Pennsylvania during 1980-82. Volatile organic compounds were detected in all three aquifer units of the Potomac-Raritan-Magoth aquifer system in the study area. Most of the contamination appears to be confined to the outcrop area at present. Low levels of contamination, however, were found downdip of the outcrop area in the upper and middle aquifers. Trichloroethylene, tetrachloroethylene, and benzene were the most frequently detected compounds. Differences in the areal distributions of light chlorinated hydrocarbons, such as trichloroethylene, and aromatic hydrocarbons, such as benzene, were noted and are probably due to differences in the uses of the compounds and the distribution patterns of potential contamination sources. The distribution patterns of volatile organic compounds differed greatly among the three aquifer units. The upper aquifer, which crops out mostly in less-developed areas, had the lowest percentage of wells with volatile organic compounds detected (10 percent of wells sampled). The concentrations in most wells in the upper aquifer which had detectable levels were less than 10 ??g/l. In the middle aquifer, which crops out beneath much of the urban and industrial area adjacent to the Delaware River, detectable levels of volatile organic compounds were found in 22 percent of wells sampled, and several wells contained concentrations above 100 ??g/l. The lower aquifer, which is confined beneath much of the outcrop area of the aquifer system, had the highest percentage of wells (28 percent) with detectable levels. This is probably due to (1) vertical leakage of contamination from the middle aquifer, and (2) the high percentage of wells tapping the lower aquifer in the most heavily developed areas of the outcrop.

  11. Effect of sonication on the photo-catalytic mineralization of some chlorinated organic compounds.

    PubMed

    Hirano, Katsuhiko; Nitta, Hidenori; Sawada, Katsuya

    2005-03-01

    Effects of the irradiation of ultrasound (US) on the photo-catalytic mineralization of some chlorinated organic compounds such as dichloroethane, tri- and tetrachloroethylenes, chloroacetic acids and chloromethanes were examined in oxygen saturated aqueous solutions suspended titanium dioxide (P25) particles. The yields of the sonochemical mineralization for these compounds were found to be extremely low compared to the photo-catalysis. However, the pre-sonication, US irradiation on the sample solution before the photo-irradiation, enhanced significantly the following photo-catalytic degradation to the complete oxidation. The effect was investigated in detail and it was found that the effect was mainly owing to the increase in the capability of the catalysis of which particles were sparsely dispersed by the sonication. The other contribution of the pre-sonication effect was found to be "pre-sonolysis", the initial formation of some intermediated products sonochemically, which are oxidizable more rapidly further to carbon dioxide than the original compound by the following photo-catalytic reactions. The pre-sonolysis effect was observed remarkably for trichloroacetic acid and tetrachloromethane, both of which are known to be hardly reactive to the photo-catalytic degradation. The photo-catalytic degradation with simultaneous sonication were also carried out for these compounds. The synergetic effect in the mineralization was observed both for carbontetrachloride and for trichloroacetic acid, the higher carbon dioxide yield being obtained in the simultaneous reaction than the sum of the yields in the photo-catalysis and the sonolysis each alone, while no significant synergetic effect was observed in the mineralization of other compounds. PMID:15501709

  12. Sulfur dioxide, hydrogen sulfide, total reduced sulfur, chlorinated hydrocarbons and photochemical oxidants in southern California museums

    NASA Astrophysics Data System (ADS)

    Hisham, Mohamed W. M.; Grosjean, Daniel

    Indoor and outdoor concentrations of the air pollutants ozone, NO 2, SO 2, H 2S, total reduced sulfur (TRS), peroxyacetyl nitrate (PAN), methyl chloroform and tetrachloroethylene, have been measured at three southern California museums. Indoor maxima were 175 ppb for NO 2, 77 ppb for O 3, 0.7 ppb for PAN, 1.2 ppb for C 2Cl 4, >6.3 ppb for CH 3CCl 3, 2.5 ppb for SO 2, 1.4 ppb for TRS, and 46 ppt for H 2S. Indoor levels and indoor/outdoor ( I/ O) ratios for the chlorinated hydrocarbons pointed out to indoor sources. Outdoor and indoor levels of SO 2 and TRS were low at all three museums, but I/ O ratios for SO 2 were high and averaged 0.89. H 2S concentrations were low, 16-46 ppt at one museum and less than 6 ppt at the other two museums. I/ O ratios for the air pollutants with outdoor sources (ozone, PAN and NO 2) showed substantial variations, from low values of 0.02-0.33 at locations without influx of outdoor air to high values of 0.85-0.88 at locations experiencing high influx of outdoor air. Of the 10 institutions we have surveyed in southern California to date, eight exhibit high I/ O ratios, e.g. 0.60-1.00 for PAN. Of the four museums surveyed that were equipped with HVAC and chemical filtration, only two yielded the expected low I/ O ratios.

  13. Savannah River Site DNAPL technical program plan

    SciTech Connect

    Jordan, J.E.; Looney, B.B.; Rossabi, J.; Bergren, C.L.

    1993-12-31

    This document was developed by the environmental remediation and technology development organizations at the Savannah River Site (SRS) and is the Site technical program plan to address the remediation of residual chlorinated hydrocarbon solvents in the groundwater and the soil. These solvents are often labeled dense nonaqueous phase liquids (DNAPLs). At SRS, the primary DNAPL constituents of concern are trichloroethylene (TCE) and tetrachloroethylene (PCE); two commonly used industrial organic solvents. The goal of the technical program plan is to provide clear objectives for DNAPL characterization and remediation activities at SRS. Developed by a task team of researchers at SRS, the objectives and program description document a coordinated, programmatic approach to identify solutions to the complex problem of DNAPL contamination. The purposes of this program are to expedite the development and application of technologies for DNAPL characterization and remediation, to provide a well characterized {open_quotes}real{close_quotes} site to perform the work, and to facilitate DNAPL remediation at SRS. Given the appropriate resources, SRS will provide an intelligent application of technical skills and confidence toward the remediation of DNAPLS. We have completed an initial characterization of DNAPLs that provides unique data on the location, nature, and extent of DNAPL occurrences at a field site. Future activities will leverage the initial characterization data for DNAPLs at SRS to demonstrate efficient progression through the characterization phase leading to cleanup. The initial characterization data provides a tool to focus this program`s activities. As a result, solutions to the complex problem of DNAPL contamination will be tested and demonstrated in the most cost-effective manner. Where appropriate, the program will rely on identifying and utilizing innovative technologies developed by industry and universities.

  14. Biodesulfurization techniques: Application of selected microorganisms for organic sulfur removal from coals. Final report

    SciTech Connect

    Elmore, B.B.

    1993-08-01

    As an alternative to post-combustion desulfurization of coal and pre-combustion desulfurization using physicochemical techniques, the microbial desulfurization of coal may be accomplished through the use of microbial cultures that, in an application of various microbial species, may remove both the pyritic and organic fractions of sulfur found in coal. Organisms have been isolated that readily depyritize coal but often at prohibitively low rates of desulfurization. Microbes have also been isolated that may potentially remove the organic-sulfur fraction present in coal (showing promise when acting on organic sulfur model compounds such as dibenzothiophene). The isolation and study of microorganisms demonstrating a potential for removing organic sulfur from coal has been undertaken in this project. Additionally, the organisms and mechanisms by which coal is microbially depyritized has been investigated. Three cultures were isolated that grew on dibenzothiophene (DBT), a model organic-sulfur compound, as the sole sulfur source. These cultures (UMX3, UMX9, and IGTS8) also grew on coal samples as the sole sulfur source. Numerous techniques for pretreating and ``cotreating`` coal for depyritization were also evaluated for the ability to improve the rate or extent of microbial depyritization. These include prewashing the coal with various solvents and adding surfactants to the culture broth. Using a bituminous coal containing 0.61% (w/w) pyrite washed with organic solvents at low slurry concentrations (2% w/v), the extent of depyritization was increased approximately 25% in two weeks as compared to controls. At slurry concentrations of 20% w/v, a tetrachloroethylene treatment of the coal followed by depyritization with Thiobacillus ferrooxidans increased both the rate and extent of depyritization by approximately 10%.

  15. Characterization of anaerobic chloroethene-dehalogenating activity in several subsurface sediments

    SciTech Connect

    Skeen, R.S.; Gao, J.; Hooker, B.S.; Quesenberry, R.D.

    1996-11-01

    Anaerobic microcosms of subsurface soils from four locations were used to investigate the separate effects of several electron donors on tetrachloroethylene (PCE) dechlorination activity. The substrates tested were methanol, formate, lactate, acetate, and sucrose. Various levels of sulfate-reducing, acetogenic, fermentative, and methanogenic activity were observed in all sediments. PCE dechlorination was detected in all microcosms, but the amount of dehalogenation varied by several orders of magnitude. Trichloroethylene was the primary dehalogenation product; however, small amounts of cis-1,2-dichloroethylene, 1,1-dichloroethylene, and vinyl chloride were also detected in several microcosms. Lactate-amended microcosms showed large amounts of dehalogenation. in three of the four sediments. One of the two sediments which showed positive activity with lactate also had large amounts of delialogenation with methanol. Sucrose, formate, and acetate also stimulated large amounts of delialogenation in one sediment that showed activity with lactate. These results suggest that lactate may be an appropriate substrate for screening sediments for PCE or TCE delialogenation activity, but that the microbial response is not sufficient for complete in situ bioremediation. A detailed study of the Victoria activity revealed that delialogenation rates were more similar to the Cornell culture than to rates measured for methanogens, or a methanol-enriched sediment culture. This may suggest that these sediments contain a highly efficient delialogenation activity similar to the Cornell culture. This assertion is supported further by the fact that an average of 3% of added reducing equivalents could be diverted to dehalogenation in tests which were conducted using PCE-saturated hexadecane as a constant source of PCE during incubation. Further evidence is needed to confirm this premise. The application of these results to in situ bioremediation of highly contaminated areas are discussed.

  16. Characterization of the methanotrophic bacterial community present in a trichloroethylene-contaminated subsurface groundwater site.

    PubMed Central

    Bowman, J P; Jiménez, L; Rosario, I; Hazen, T C; Sayler, G S

    1993-01-01

    Groundwater, contaminated with trichloroethylene (TCE) and tetrachloroethylene (PCE), was collected from 13 monitoring wells at Area M on the U.S. Department of Energy Savannah River Site near Aiken, S.C. Filtered groundwater samples were enriched with methane, leading to the isolation of 25 methanotrophic isolates. The phospholipid fatty acid profiles of all the isolates were dominated by 18:1 omega 8c (60 to 80%), a signature lipid for group II methanotrophs. Subsequent phenotypic testing showed that most of the strains were members of the genus Methylosinus and one isolate was a member of the genus Methylocystis. Most of the methanotroph isolates exhibited soluble methane monooxygenase (sMMO) activity. This was presumptively indicated by the naphthalene oxidation assay and confirmed by hybridization with a gene probe encoding the mmoB gene and by cell extract assays. TCE was degraded at various rates by most of the sMMO-producing isolates, whereas PCE was not degraded. Savannah River Area M and other groundwaters, pristine and polluted, were found to support sMMO activity when supplemented with nutrients and then inoculated with Methylosinus trichosporium OB3b. The maximal sMMO-specific activity obtained in the various groundwaters ranged from 41 to 67% compared with maximal rates obtained in copper-free nitrate mineral salts media. This study partially supports the hypothesis that stimulation of indigenous methanotrophic communities can be efficacious for removal of chlorinated aliphatic hydrocarbons from subsurface sites and that the removal can be mediated by sMMO. PMID:8368829

  17. Reconnaissance of volatile organic compounds in the subsurface at Rutgers University, Busch Campus, Piscataway Township, New Jersey

    USGS Publications Warehouse

    dePaul, V.T.

    1996-01-01

    During 1991-92, the U.S. Geological Survey conducted a hydrogeologic reconnaissance at a site near the Rutgers University, Busch Campus, Chemical Engineering building, C-Wing. Results of analyses of the soil-gas samples, which were collected at 43 locations, indicated the presence of volatile organic compounds, primarily carbon tetrachloride, near the C-Wing building and about 550 feet downgradient from and southwest of the C-Wing building. Concentrations of the compound in soil-gas samples were highest (2.1 ug/L (micrograms per liter)) along the southwestern wall of the C-Wing building. Ground-water samples were collected at depths as great as 55 feet from five wells and piezometers near the C-Wing building. Samples collected along the southwestern wall of the building also contained the highest concentrations of volatile organic compounds. Concentrations of carbon tetrachloride in the ground-water samples ranged from < 0.35 ug/L to 3,400 ug/L, and concentrations of tetrachloro- ethylene ranged from < 0.28 ug/L to 85 ug/L. Ground-water samples collected at depths of 55 feet or more from two wells located on the Rutgers University Golf Course about 2,400 feet down- gradient from the C-Wing building contained concentrations of tetrachloroethylene as great as 17.7 ug/L. Water levels measured in six wells and six piezometers indicated that the general flow direction in the shallow part of the aquifer is to the southwest of the C-Wing building. An electrical-resistivity survey was conducted by azimuthal resistivity techniques. The results of the survey were consistent with field measurements, and the dominant vertical fractures near the Busch Campus trend northeast. An electromagnetic survey was ineffective as a result of cultural interferences and could not be used to determine the hydrogeologic characteristics of the site.

  18. Application of a new vertical profiling tool (ESASS) for sampling groundwater quality during hollow-stem auger drilling

    USGS Publications Warehouse

    Harte, P.T.; Flanagan, S.M.

    2011-01-01

    A new tool called ESASS (Enhanced Screen Auger Sampling System) was developed by the U.S. Geological Survey. The use of ESASS, because of its unique U.S. patent design (U.S. patent no. 7,631,705 B1), allows for the collection of representative, depth-specific groundwater samples (vertical profiling) in a quick and efficient manner using a 0.305-m long screen auger during hollow-stem auger drilling. With ESASS, the water column in the flights above the screen auger is separated from the water in the screen auger by a specially designed removable plug and collar. The tool fits inside an auger of standard inner diameter (82.55 mm). The novel design of the system constituted by the plug, collar, and A-rod allows the plug to be retrieved using conventional drilling A-rods. After retrieval, standard-diameter (50.8 mm) observation wells can be installed within the hollow-stem augers. Testing of ESASS was conducted at one waste-disposal site with tetrachloroethylene (PCE) contamination and at two reference sites with no known waste-disposal history. All three sites have similar geology and are underlain by glacial, stratified-drift deposits. For the applications tested, ESASS proved to be a useful tool in vertical profiling of groundwater quality. At the waste site, PCE concentrations measured with ESASS profiling at several depths were comparable (relative percent difference <25%) to PCE concentrations sampled from wells. Vertical profiling with ESASS at the reference sites illustrated the vertical resolution achievable in the profile system; shallow groundwater quality varied by a factor of five in concentration of some constituents (nitrate and nitrite) over short (0.61 m) distances. Ground Water Monitoring & Remediation ?? 2011, National Ground Water Association. No claim to original US government works.

  19. Application of a new vertical profiling tool (ESASS) for sampling groundwater quality during hollow-stem auger drilling

    USGS Publications Warehouse

    Harte, Philip T.; Flanagan, Sarah M.

    2011-01-01

    A new tool called ESASS (Enhanced Screen Auger Sampling System) was developed by the U.S. Geological Survey. The use of ESASS, because of its unique U.S. patent design (U.S. patent no. 7,631,705 B1), allows for the collection of representative, depth-specific groundwater samples (vertical profiling) in a quick and efficient manner using a 0.305-m long screen auger during hollow-stem auger drilling. With ESASS, the water column in the flights above the screen auger is separated from the water in the screen auger by a specially designed removable plug and collar. The tool fits inside an auger of standard inner diameter (82.55 mm). The novel design of the system constituted by the plug, collar, and A-rod allows the plug to be retrieved using conventional drilling A-rods. After retrieval, standard-diameter (50.8 mm) observation wells can be installed within the hollow-stem augers. Testing of ESASS was conducted at one waste-disposal site with tetrachloroethylene (PCE) contamination and at two reference sites with no known waste-disposal history. All three sites have similar geology and are underlain by glacial, stratified-drift deposits. For the applications tested, ESASS proved to be a useful tool in vertical profiling of groundwater quality. At the waste site, PCE concentrations measured with ESASS profiling at several depths were comparable (relative percent difference <25%) to PCE concentrations sampled from wells. Vertical profiling with ESASS at the reference sites illustrated the vertical resolution achievable in the profile system; shallow groundwater quality varied by a factor of five in concentration of some constituents (nitrate and nitrite) over short (0.61 m) distances.

  20. Survey of bottled drinking water sold in Canada. Part 2. Selected volatile organic compounds

    SciTech Connect

    Page, B.D.; Conacher, H.B.S.; Salminen, J. [Health and Welfare Canada, Ottawa, Ontario (Canada)] [and others

    1993-01-01

    Selected volatile organic compound (VOC) contaminants were determined in 182 samples of retail bottled waters purchased in Canada. Samples included spring water (86) packaged in containers of polyethylene or in smaller containers of transparent plastic or glass, mineral water (61) packaged only in transparent plastic or glass, and miscellaneous bottled waters (35). Analyses were performed by 3 laboratories, each using headspace sampling and capillary gas chromatography with either mass spectrometric (1 laboratory) or flame ionization detection with mass spectrometric confirmation, if required (2 laboratories). Benzene, the contaminant of primary interest, was detected in only 1 of the 182 samples at 2 {mu}g/kg. Other VOC contaminants detected (number of positive samples, average, and range of positives in {mu}g/kg) included toluene (20, 6.92, 0.5-63), cyclohexane (23, 39.2, 3-108), chloroform (12, 25.8, 3.7-70), and dichloromethane (4, 59, 22-97). Cyclohexane was found in the plastic and as a migrant from the plastic in 20 samples of spring water, but it was found in only 1 of 61 mineral water samples analyzed at only 3 {mu}g/kg/. Chloroform was found almost exclusively in samples that could have been obtained from public water supplies. It was not found in mineral water samples, but it was found in 1 spring water sample at 3.7 {mu}g/kg. The source of the toluene contamination was not known. Other VOCs detected include ethanol and limonene, associated with added flavoring; pentane, as a migrant from a foamed polystyrene cap liner; and 1,1,2,2-tetra-chloroethylene in a sample of demineralized water. 10 refs., 6 tabs.

  1. An anaerobic field injection experiment in a landfill leachate plume, Grindsted, Denmark: 1. Experimental setup, tracer movement, and fate of aromatic and chlorinated compounds

    NASA Astrophysics Data System (ADS)

    Rügge, Kirsten; Bjerg, Poul L.; Pedersen, JøRn K.; MosbæK, Hans; Christensen, Thomas H.

    1999-04-01

    A continuous, natural-gradient field injection experiment, involving 18 xenobiotic compounds and bromide as tracers, was performed in the anaerobic region of a leachate plume downgradient from the Grindsted Landfill, Denmark. The injection lasted for 195 days, and within this period a continuous cloud was established. Over a period of 924 days the cloud movement was monitored in approximately 70 discrete sampling points in the central part of the cloud, and the spatial distribution was described by seven cloud snapshots involving 400-700 sampling points. The bromide cloud movement closely followed the varying flow direction predicted by the water table measurements. Moment analysis showed decreasing tracer flow velocities and reduced capture of bromide mass with time, which may be explained by varying flow conditions (direction, hydraulic gradient) and the heterogeneous geological conditions in the sandy aquifer. Naphthalene, having the highest log Kow value, was the most retarded compound, with a retardation of less than 10%. Therefore sorption was not considered to be a significant attenuation process for any of the compounds studied. Transformation under iron-reducing conditions was observed for toluene, o-xylene, TeCM, 1,1,1-TCA, PCE, and TCE, while transformation of benzene and napthalene was not detected in the aquifer within the time frame of this study. First-order transformation rates were in the range of 0.028-0.039 d-1 and 0.0014-0.0028 d-1 for the aromatic compounds toluene and o-xylene, respectively. The rates for the chlorinated aliphatic compounds, tetrachloromethane, 1,1,1- trichloroethane, tetrachloroethylene, and trichloroethylene, were >0.7 d-1, 0.0044-0.0054 d-1, 0.0012-0.0038 d-1, and 0.0003-0.001 d-1, respectively. Long lag periods and slow transformation rates were observed for some of the compounds, suggesting that lack of transformation reported in the literature may be attributable to short experimental periods in those studies.

  2. Simultaneous analysis of 28 urinary VOC metabolites using ultra high performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC-ESI/MSMS).

    PubMed

    Alwis, K Udeni; Blount, Benjamin C; Britt, April S; Patel, Dhrusti; Ashley, David L

    2012-10-31

    Volatile organic compounds (VOCs) are ubiquitous in the environment, originating from many different natural and anthropogenic sources, including tobacco smoke. Long-term exposure to certain VOCs may increase the risk for cancer, birth defects, and neurocognitive impairment. Therefore, VOC exposure is an area of significant public health concern. Urinary VOC metabolites are useful biomarkers for assessing VOC exposure because of non-invasiveness of sampling and longer physiological half-lives of urinary metabolites compared with VOCs in blood and breath. We developed a method using reversed-phase ultra high performance liquid chromatography (UPLC) coupled with electrospray ionization tandem mass spectrometry (ESI/MSMS) to simultaneously quantify 28 urinary VOC metabolites as biomarkers of exposure. We describe a method that monitors metabolites of acrolein, acrylamide, acrylonitrile, benzene, 1-bromopropane, 1,3-butadiene, carbon-disulfide, crotonaldehyde, cyanide, N,N-dimethylformamide, ethylbenzene, ethylene oxide, propylene oxide, styrene, tetrachloroethylene, toluene, trichloroethylene, vinyl chloride and xylene. The method is accurate (mean accuracy for spiked matrix ranged from 84 to 104%), sensitive (limit of detection ranged from 0.5 to 20 ng mL(-1)) and precise (the relative standard deviations ranged from 2.5 to 11%). We applied this method to urine samples collected from 1203 non-smokers and 347 smokers and demonstrated that smokers have significantly elevated levels of tobacco-related biomarkers compared to non-smokers. We found significant (p<0.0001) correlations between serum cotinine and most of the tobacco-related biomarkers measured. These findings confirm that this method can effectively quantify urinary VOC metabolites in a population exposed to volatile organics. PMID:23062436

  3. Characterization of the Chronic Risk and Hazard of Hazardous Air Pollutants in the United States Using Ambient Monitoring Data

    PubMed Central

    McCarthy, Michael C.; O’Brien, Theresa E.; Charrier, Jessica G.; Hafner, Hilary R.

    2009-01-01

    Background Ambient measurements of hazardous air pollutants (air toxics) have been used to validate model-predicted concentrations of air toxics but have not been used to perform risk screening at the national level. Objectives We used ambient concentrations of routinely measured air toxics to determine the relative importance of individual air toxics for chronic cancer and noncancer exposures. Methods We compiled 3-year averages for ambient measurement of air toxics collected at monitoring locations in the United States from 2003 through 2005. We then used national distributions of risk-weighted concentrations to identify the air toxics of most concern. Results Concentrations of benzene, carbon tetrachloride, arsenic, 1,3-butadiene, and acetaldehyde were above the 10?6 cancer risk level at most sites nationally with a high degree of confidence. Concentrations of tetrachloroethylene, ethylene oxide, acrylonitrile, and 1,4-dichlorobenzene were also often greater than the 10?6 cancer risk level, but we have less confidence in the estimated risk associated with these pollutants. Formaldehyde and chromium VI concentrations were either above or below the 10?6 cancer risk level, depending on the choice of agency-recommended 10?6 level. The method detection limits of eight additional pollutants were too high to rule out that concentrations were above the 10?6 cancer risk level. Concentrations of 52 compounds compared with chronic noncancer benchmarks indicated that only acrolein concentrations were greater than the noncancer reference concentration at most monitoring sites. Conclusions Most pollutants with national site-level averages greater than health benchmarks were also pollutants of concern identified in modeled national-scale risk assessments. Current monitoring networks need more sensitive ambient measurement techniques to better characterize the air toxics problem in the United States. PMID:19479023

  4. Locally-calibrated light transmission visualization methods to quantify nonaqueous phase liquid mass in porous media

    NASA Astrophysics Data System (ADS)

    Wang, Huaguo; Chen, Xiaosong; Jawitz, James W.

    2008-11-01

    Five locally-calibrated light transmission visualization (LTV) methods were tested to quantify nonaqueous phase liquid (NAPL) mass and mass reduction in porous media. Tetrachloroethylene (PCE) was released into a two-dimensional laboratory flow chamber packed with water-saturated sand which was then flushed with a surfactant solution (2% Tween 80) until all of the PCE had been dissolved. In all the LTV methods employed here, the water phase was dyed, rather than the more common approach of dyeing the NAPL phase, such that the light adsorption characteristics of NAPL did not change as dissolution progressed. Also, none of the methods used here required the use of external calibration chambers. The five visualization approaches evaluated included three methods developed from previously published models, a binary method, and a novel multiple wavelength method that has the advantage of not requiring any assumptions about the intra-pore interface structure between the various phases (sand/water/NAPL). The new multiple wavelength method is also expected to be applicable to any translucent porous media containing two immiscible fluids (e.g., water-air, water-NAPL). Results from the sand-water-PCE system evaluated here showed that the model that assumes wetting media of uniform pore size (Model C of Niemet and Selker, 2001) and the multiple wavelength model with no interface structure assumptions were able to accurately quantify PCE mass reduction during surfactant flushing. The average mass recoveries from these two imaging methods were greater than 95% for domain-average NAPL saturations of approximately 2.6 × 10 - 2 , and were approximately 90% during seven cycles of surfactant flushing that sequentially reduced the average NAPL saturation to 7.5 × 10 - 4 .

  5. Respiratory exposure to components of water-miscible metalworking fluids.

    PubMed

    Suuronen, Katri; Henriks-Eckerman, Maj-Len; Riala, Riitta; Tuomi, Timo

    2008-10-01

    Water-miscible metalworking fluids (MWFs) are capable of causing respiratory symptoms and diseases. Recently, much emphasis has been put on developing new methods for assessing respiratory exposure to MWF emulsions. The air concentrations of ingredients and contaminants of MWF and inhalable dust were measured in 10 metal workshops in southern Finland. Oil mist was determined by infra red spectroscopy analysis after tetrachloroethylene extraction from the filter. Aldehydes were collected on Sep-Pak chemosorbents and analysed by liquid chromatography. Volatile organic compounds (VOCs) were collected on Tenax adsorbents and analysed by gas chromatography with mass spectrometric detection after thermal desorption. Endotoxins were collected on glass fibre filter and analysed by enzyme-based spectrophotometry, and viable microbes were collected on polycarbonate filter and cultured. Inhalable dust was collected on cellulose acetate filter and quantified gravimetrically. Associations between the different exposures were calculated with Spearman's correlations. The mean concentration of oil mist was 0.14 (range <0.010-0.60) mg m(-3). The mean total concentration of aldehydes was 0.095 (0.026-0.38) mg m(-3), with formaldehyde as the main aldehyde. The average total concentration of VOC was 1.9 (0.34-4.5) mg m(-3) consisting mainly of high-boiling aliphatic hydrocarbons. Several potential sensitizing chemicals such as terpenes were found in small quantities. The concentration of microbial contaminants was low. All the measured air concentrations were below the Finnish occupational exposure limits. The exposure in machine shops was quantitatively dominated by volatile compounds. Additional measurements of MWF components such as aldehydes, alkanolamines and VOCs are needed to get more information on the chemical composition of workshops' air. New air cleaning methods should be introduced, as oil mist separators are insufficient to clean the air of small molecular impurities. PMID:18678881

  6. Attenuation of methane and volatile organic compounds in landfill soil covers.

    PubMed

    Scheutz, Charlotte; Mosbaek, Hans; Kjeldsen, Peter

    2004-01-01

    The potential for natural attenuation of volatile organic compounds (VOCs) in landfill covers was investigated in soil microcosms incubated with methane and air, simulating the gas composition in landfill soil covers. Soil was sampled at Skellingsted Landfill at a location emitting methane. In total, 26 VOCs were investigated, including chlorinated methanes, ethanes, ethenes, fluorinated hydrocarbons, and aromatic hydrocarbons. The soil showed a high capacity for methane oxidation resulting in very high oxidation rates of between 24 and 112 microg CH4 g(-1) h(-1). All lower chlorinated compounds were shown degradable, and the degradation occurred in parallel with the oxidation of methane. In general, the degradation rates of the chlorinated aliphatics were inversely related to the chlorine to carbon ratios. For example, in batch experiments with chlorinated ethylenes, the highest rates were observed for vinyl chloride (VC) and lowest rates for trichloroethylene (TCE), while tetrachloroethylene (PCE) was not degraded. Maximal oxidation rates for the halogenated aliphatic compounds varied between 0.03 and 1.7 microg g(-1) h(-1). Fully halogenated hydrocarbons (PCE, tetrachloromethane [TeCM], chlorofluorocarbon [CFC]-11, CFC-12, and CFC-113) were not degraded in the presence of methane and oxygen. Aromatic hydrocarbons were rapidly degraded giving high maximal oxidation rates (0.17-1.4 microg g(-1) h(-1)). The capacity for methane oxidation was related to the depth of oxygen penetration. The methane oxidizers were very active in oxidizing methane and the selected trace components down to a depth of 50 cm below the surface. Maximal oxidation activity occurred in a zone between 15 and 20 cm below the surface, as this depth allowed sufficient supply of both methane and oxygen. Mass balance calculations using the maximal oxidation rates obtained demonstrated that landfill soil covers have a significant potential for not only methane oxidation but also cometabolic degradation of selected volatile organics, thereby reducing emissions to the atmosphere. PMID:14964359

  7. Use of plume mapping data to estimate chlorinated solvent mass loss

    USGS Publications Warehouse

    Barbaro, J.R.; Neupane, P.P.

    2006-01-01

    Results from a plume mapping study from November 2000 through February 2001 in the sand-and-gravel surficial aquifer at Dover Air Force Base, Delaware, were used to assess the occurrence and extent of chlorinated solvent mass loss by calculating mass fluxes across two transverse cross sections and by observing changes in concentration ratios and mole fractions along a longitudinal cross section through the core of the plume. The plume mapping investigation was conducted to determine the spatial distribution of chlorinated solvents migrating from former waste disposal sites. Vertical contaminant concentration profiles were obtained with a direct-push drill rig and multilevel piezometers. These samples were supplemented with additional ground water samples collected with a minipiezometer from the bed of a perennial stream downgradient of the source areas. Results from the field program show that the plume, consisting mainly of tetrachloroethylene (PCE), trichloroethene (TCE), and cis-1,2-dichloroethene (cis-1,2-DCE), was approximately 670 m in length and 120 m in width, extended across much of the 9- to 18-m thickness of the surficial aquifer, and discharged to the stream in some areas. The analyses of the plume mapping data show that losses of the parent compounds, PCE and TCE, were negligible downgradient of the source. In contrast, losses of cis-1,2-DCE, a daughter compound, were observed in this plume. These losses very likely resulted from biodegradation, but the specific reaction mechanism could not be identified. This study demonstrates that plume mapping data can be used to estimate the occurrence and extent of chlorinated solvent mass loss from biodegradation and assess the effectiveness of natural attenuation as a remedial measure.

  8. CROWTM PROCESS APPLICATION FOR SITES CONTAMINATED WITH LIGHT NON-AQUEOUS PHASE LIQUIDS AND CHLORINATED HYDROCARBONS

    SciTech Connect

    L.A. Johnson, Jr.

    2003-06-30

    Western Research Institute (WRI) has successfully applied the CROWTM (Contained Recovery of Oily Wastes) process at two former manufactured gas plants (MGPs), and a large wood treatment site. The three CROW process applications have all occurred at sites contaminated with coal tars or fuel oil and pentachlorophenol (PCP) mixtures, which are generally denser than water and are classified as dense non-aqueous phase liquids (DNAPLs). While these types of sites are abundant, there are also many sites contaminated with gasoline, diesel fuel, or fuel oil, which are lighter than water and lie on top of an aquifer. A third site type occurs where chlorinated hydrocarbons have contaminated the aquifer. Unlike the DNAPLs found at MGP and wood treatment sites, chlorinated hydrocarbons are approximately one and a half times more dense than water and have fairly low viscosities. These contaminants tend to accumulate very rapidly at the bottom of an aquifer. Trichloroethylene (TCE) and perchloroethylene, or tetrachloroethylene (PCE), are the major industrial chlorinated solvents that have been found contaminating soils and aquifers. The objective of this program was to demonstrate the effectiveness of applying the CROW process to sites contaminated with light non-aqueous phase liquids (LNAPLs) and chlorinated hydrocarbons. Individual objectives were to determine a range of operating conditions necessary to optimize LNAPL and chlorinated hydrocarbon recovery, to conduct numerical simulations to match the laboratory experiments and determine field-scale recoveries, and determine if chemical addition will increase the process efficiency for LNAPLs. The testing consisted of twelve TCE tests; eight tests with PCE, diesel, and wood treatment waste; and four tests with a fuel oil-diesel blend. Testing was conducted with both vertical and horizontal orientations and with ambient to 211 F (99 C) water or steam. Residual saturations for the horizontal tests ranged from 23.6% PV to 0.3% PV. Also conducted was screening of 13 chemicals to determine their relative effectiveness and the selection of three chemicals for further testing.

  9. Fates of chlorinated volatile organic compounds in aerobic biological treatment processes: the effects of aeration and sludge addition.

    PubMed

    Chen, Wei-Hsiang; Yang, Wen-Ben; Yuan, Chung-Shin; Yang, Jun-Chen; Zhao, Qing-Liang

    2014-05-01

    The emission of volatile organic compounds (VOCs) from wastewater treatment plants (WWTPs) is becoming an environmental issue of increasing concern. As biological treatment has been considered as one important approach for VOC removal, lab-scale batch experiments were conducted in this study to investigate the fates of four chlorinated hydrocarbons, including chloroform, carbon tetrachloride, trichloroethylene (TCE), and tetrachloroethylene (PERC), in the biological treatment processes with respect to the effects of aeration and sludge addition. The VOC concentrations in the phases of air, water, and sludge under four simulated treatment stages (the first sedimentation, the forepart and rear part of aerobic biological treatment, and the second sedimentation) were analyzed. The results were used to understand the three-phase partitioning of these compounds and to estimate their potentials for volatilization and biological sorption and degradation in these technologies with the concept of fugacity. It was observed that the VOCs were mainly present in the water phase through the experiments. The effects of aeration or sludge addition on the fates of these VOCs occurred but appeared to be relatively limited. The concentration distributions of the VOCs were well below the reported partitioning coefficients. It was suggested that these compounds were unsaturated in the air and sludge phases, enhancing their potentials for volatilization and biological sorption/degradation through the processes. However, the properties of these chlorinated VOCs such as the volatility, polarity, or even biodegradability caused by their structural characteristics (e.g., the number of chlorine, saturated or unsaturated) may represent more significant factors for their fates in the aerobic biological treatment processes. These findings prove the complication behind the current knowledge of VOC pollutions in WWTPs and are of help to manage the adverse impacts on the environment and public health by the VOCs from these particular sources. PMID:24321332

  10. Treatment of chlorinated ethenes in groundwater with ozone and hydrogen peroxide

    SciTech Connect

    Clancy, P.B. [IBM Corp., Essex Junction, VT (United States); Armstrong, J.; Couture, M. [Dartmouth College, Hanover, NH (United States)] [and others

    1996-12-31

    A study was conducted to enhance the performance of an advanced oxidation process in treating chlorinated ethenes in groundwater at IBM`s groundwater treatment system at its Essex Junction, Vermont facility. A model describing the reaction kinetics and mass transfer of a co-current ozone injection process is presented. This model, in conjunction with experiments, demonstrates that the treatment performance of the ozone treatment process at a given ozone/air concentration and ozone mass flowrate cannot be improved by varying process operating parameters such as number of ozone injectors utilized, use of a static mixer, or variation of groundwater flowrate through each injector. This is because dissolved ozone reaches equilibrium with the injected ozone/air mixture within two seconds of initial contact. Also, the Venturi-type ozone injection system presently in use destroys nearly half of the injected ozone. Injection of hydrogen peroxide in conjunction with ozone increases the overall tetrachloroethylene (PCE) treatment efficiency by a factor of four (in comparison to ozone alone) at a H{sub 2}O{sub 2}/O{sub 3} mass ratio of between 1 and 2. Treatment of trichloroethylene (TCE) is enhanced by a factor of two. This enhancement of the oxidative treatment process results in a reduction in solvent mass load to a granular activated carbon (GAC) adsorption system located downstream, thus potentially reducing the usage GAC and regeneration of spent GAC. However, residual hydrogen peroxide and/or hydroxyl free radicals from the oxidation process effluent may interact adversely with certain grades of GAC; the causes of this interaction and methods to attenuate it (i.e., the use of more resistant grades of GAC) are discussed. Overall O{sub 3}/H{sub 2}O{sub 2}/GAC system operating costs can potentially be reduced significantly (up to $20K annually). An economic analysis and system operation/cost optimization study are presented. 8 refs., 7 figs., 1 tab.

  11. A method for quantification of volatile organic compounds in blood by SPME-GC-MS/MS with broader application: From non-occupational exposure population to exposure studies.

    PubMed

    Aranda-Rodriguez, Rocio; Cabecinha, Ashley; Harvie, Jeromy; Jin, Zhiyun; Marchand, Axelle; Tardif, Robert; Nong, Andy; Haddad, Sami

    2015-06-15

    Humans are continuously exposed to volatile organic compounds (VOCs) as these chemicals are ubiquitously present in most indoor and outdoor environments. In order to assess recent exposure to VOCs for population-based studies, VOCs are measured in the blood of participants. This work describes an improved method to detect 12 VOCs by head-space solid-phase microextraction gas chromatography coupled with isotope-dilution mass spectrometry in selected reaction monitoring mode (SPME-GC-MS/MS). This method was applied to the analysis of trihalomethanes, styrene, trichloroethylene, tetrachloroethylene and BTEX (benzene, toluene, ethylbenzene, m-xylene, p-xylene, o-xylene) in a population-based biomonitoring study (Canadian Health Measures Survey). The method showed good linearity (>0.990) in the range of 0.010-10?g/L and detection limits between 0.007 and 0.027?g/L, precision better than 25% and good accuracy (±25%) based on proficiency testing materials. Quality Control data among runs over a 7 month period showed %RSD between 14 and 25% at low levels (?0.03?g/L) and between 9 and 23% at high levels (?0.4?g/L). The method was modified to analyze samples from a pharmacokinetic study in which 5 healthy volunteers were exposed to single, binary and quaternary mixtures of CTEX (chloroform, ethylbenzene, toluene and m-xylene), thus the expected concentration in blood was 1 order of magnitude higher than those found in the general population. The method was modified by reducing the sample size (from 3g to 0.5g) and increasing the upper limit of the concentration range to 395?g/L. Good linearity was found in the range of 0.13-395?g/L for toluene and ethylbenzene and 0.20-609?g/L for m/p-xylene. Quality control data among runs over the period of the study (n=13) were found to vary between 7 and 25%. PMID:25965874

  12. Asthma symptoms in Hispanic children and daily ambient exposures to toxic and criteria air pollutants.

    PubMed Central

    Delfino, Ralph J; Gong, Henry; Linn, William S; Pellizzari, Edo D; Hu, Ye

    2003-01-01

    Although acute adverse effects on asthma have been frequently found for the U.S. Environmental Protection Agency's principal criteria air pollutants, there is little epidemiologic information on specific hydrocarbons from toxic emission sources. We conducted a panel study of 22 Hispanic children with asthma who were 10-16 years old and living in a Los Angeles community with high traffic density. Subjects filled out symptom diaries daily for up to 3 months (November 1999 through January 2000). Pollutants included ambient hourly values of ozone, nitrogen dioxide, sulfur dioxide, and carbon monoxide and 24-hr values of volatile organic compounds (VOCs), particulate matter with aerodynamic diameter < 10 microm (PM10, and elemental carbon (EC) and organic carbon (OC) PM10 fractions. Asthma symptom severity was regressed on pollutants using generalized estimating equations, and peak expiratory flow (PEF) was regressed on pollutants using mixed models. We found positive associations of symptoms with criteria air pollutants (O3, NO2, SO2, PM10), EC-OC, and VOCs (benzene, ethylbenzene, formaldehyde, acetaldehyde, acetone, 1,3-butadiene, tetrachloroethylene, toluene, m,p-xylene, and o-xylene). Selected adjusted odds ratios for bothersome or more severe asthma symptoms from interquartile range increases in pollutants were, for 1.4 ppb 8-hr NO2, 1.27 [95% confidence interval (CI), 1.05-1.54]; 1.00 ppb benzene, 1.23 (95% CI, 1.02-1.48); 3.16 ppb formaldehyde, 1.37 (95% CI, 1.04-1.80); 37 microg/m3 PM10, 1.45 (95% CI, 1.11-1.90); 2.91 microg/m3 EC, 1.85 (95% CI, 1.11-3.08); and 4.64 microg/m3 OC, 1.88 (95% CI, 1.12-3.17). Two-pollutant models of EC or OC with PM10 showed little change in odds ratios for EC (to 1.83) or OC (to 1.89), but PM10 decreased from 1.45 to 1.0. There were no significant associations with PEF. Findings support the view that air toxins in the pollutant mix from traffic and industrial sources may have adverse effects on asthma in children. PMID:12676630

  13. In-situ characterization using pulsed laser systems and hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Chinni, Rosemarie Catherine

    We are investigating the use of resonance-enhanced multiphoton ionization (REMPI) to detect volatile organic compounds (VOCs) mainly BTEX compounds (benzene, toluene, ethylbenzene, o-, m -, and p-xylenes) and some organochlorides, such as tetrachloroethylene (PCE), trichloroethylene (TCE), and carbon tetrachloride, found in the environment. The long term objective of this work is to develop a system for measuring and identifying a wide range of VOCs at part-per-billion levels in the environment in-situ in the subsurface. The specific focus of this work is to identify and optimize the experimental parameters that affect the determination of these organic compounds using the REMPI technique. REMPI is a spectroscopic technique that is advantageous for in-situ analyses involving VOCs found as contaminants in the environment. REMPI can give quantitative and qualitative information about these compounds and it has the capability to detect specific contaminants and distinguish them from other species in the sample. The REMPI technique is well-suited to detect these compounds since selective ionization of the species of interest occurs. This research involves the development of a fiber-optic REMPI probe. Our current prototypes include lensed and non-lensed probe designs. However, the main focus of this dissertation is the optimization of the non-lensed probe design. The primary volatile organic compounds that this dissertation will address are the BTEX compounds, benzene, toluene, ethylbenzene, and o-, m-, and p-xylenes. These VOCs will be analyzed using REMPI in order to determine the best conditions and parameters appropriate for each species. This involves the determination of the optimal laser wavelength for each species, both alone and in mixtures. For these studies, partial least squares (PLS) multivariate calibration is used to examine the REMPI excitation scans of various mixtures of BTEX compounds. Hyperspectral imaging and laser-induced fluorescence are also discussed in this dissertation. The study involving hyperspectral imaging demonstrates a novel way to make 2-dimensional temperature "maps" of flames using a dimension reduction fiber array by measuring iron emission from the flame. Laser ablation along with LIF are performed together to monitor the effect of flame retardant chemicals in the combustion environment by measuring OH radical fluorescence and fluorescent lifetime.

  14. In-Situ Anaerobic Biosurfactant Production Process For Remediation Of DNAPL Contamination In Subsurface Aquifers

    NASA Astrophysics Data System (ADS)

    Albino, J. D.; Nambi, I. M.

    2009-12-01

    Microbial Enhanced Oil Recovery (MEOR) and remediation of aquifers contaminated with hydrophobic contaminants require insitu production of biosurfactants for mobilization of entrapped hydrophobic liquids. Most of the biosurfactant producing microorganisms produce them under aerobic condition and hence surfactant production is limited in subsurface condition due to lack of oxygen. Currently bioremediation involves expensive air sparging or excavation followed by exsitu biodegradation. Use of microorganisms which can produce biosurfactants under anaerobic conditions can cost effectively expedite the process of insitu bioremediation or mobilization. In this work, the feasibility of anaerobic biosurfactant production in three mixed anaerobic cultures prepared from groundwater and soil contaminated with chlorinated compounds and municipal sewage sludge was investigated. The cultures were previously enriched under complete anaerobic conditions in the presence of Tetrachloroethylene (PCE) for more than a year before they were studied for biosurfactant production. Biosurfactant production under anaerobic conditions was simulated using two methods: i) induction of starvation in the microbial cultures and ii) addition of complex fermentable substrates. Positive result for biosurfactant production was not observed when the cultures were induced with starvation by adding PCE as blobs which served as the only terminal electron acceptor. However, slight reduction in interfacial tension was noticed which was caused by the adherence of microbes to water-PCE interface. Biosurfactant production was observed in all the three cultures when they were fed with complex fermentable substrates and surface tension of the liquid medium was lowered below 35 mN/m. Among the fermentable substrates tested, vegetable oil yielded highest amount of biosurfactant in all the cultures. Complete biodegradation of PCE to ethylene at a faster rate was also observed when vegetable oil was amended to the microbial cultures. The microorganisms responsible for biosurfactant production was isolated and identified as Pseudomonas Sp (designated as Pseudomonas Sp ANBIOSURF-1, Gene bank no: FJ930079), Pseudomonas stutzeri (MTCC 10033), Pseudomonas Sp (MTCC 10032) from groundwater, soil and municipal sewage sludge enrichments respectively. This study confirms that biosurfactants can be produced under anaerobic conditions and also in sufficient quantities. The cultures were also able to cometabolically degrade PCE to Ethylene. The isolated microorganisms can be used for remediation of DNAPL contaminated sites by in-situ biosurfactant production.

  15. Assessing the Use of Dry Wells as a Tool for Stormwater Management and Groundwater Recharge in Urban Areas

    NASA Astrophysics Data System (ADS)

    Edwards, E.; Harter, T.; Fogg, G. E.; Washburn, B.; Bryson, R.; Meirovitz, C.; Fawcett, J.; Kretsinger Grabert, V. J.; Bowles, C.; Carr, M.; Nelson, C.

    2014-12-01

    Dry wells are gravity-fed, excavated pits with perforated casings used to facilitate stormwater infiltration and groundwater recharge in areas comprised primarily of impermeable surfaces or low permeability soils. Stormwater runoff that would otherwise be routed to streams or drains in urban areas is used as a source of aquifer recharge. However, the potential for groundwater contamination caused by urban runoff bypassing surface soil filtration has prevented more widespread use of dry wells as a recharge mechanism. We present the results of a literature survey to assess the potential of dry wells for safe stormwater recharge. Dry wells have been inculpated in groundwater contamination events, although accusations were typically not backed by scientific data. In 1989 groundwater in Modesto, CA, was contaminated with tetrachloroethylene from a dry cleaning facility. The city had been using dry wells to manage stormwater for more than 50 years without detrimental impacts before the contamination. A USGS monitoring study proved that the contamination was from sewer system leakage, and did not involve the dry wells. Some areas of the country have used dry wells with positive results. The Underground Injection Control system (UICs) study in Portland, OR, has been active for ten years, and currently operates over 9,000 UICs. Initially, a ten foot separation distance was enforced between the seasonal high water table and the bottom perforation of the UIC; however, due to monitoring and modeling results that indicate the protectiveness of groundwater, this distance has been reduced to zero feet. Future work will include a comparative pilot study involving a residential and an industrial site in Elk Grove, CA. The study will use modeling tools to assess the recharge potential and groundwater protectiveness of dry wells. Both sites are outfitted with four monitoring wells each: an upgradient monitoring well, two downgradient monitoring wells, and a vadose zone monitoring well. The results of water quality sampling will determine the contaminants of interest, and a model of the fate and transport of these contaminants in the vadose zone will be coupled with hydraulic models to estimate the response of the hydrogeologic system to dry well recharge, with the goal of creating a tool that can be used to evaluate future dry well locations.

  16. Assessing the vulnerability of public-supply wells to contamination—High Plains Aquifer near York, Nebraska

    USGS Publications Warehouse

    Jagucki, Martha L.; Landon, Matthew K.; Clark, Brian R.; Eberts, Sandra M.

    2008-01-01

    The U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program found, in studies from 1991 to 2001, low levels of mixtures of contaminants in ground water near the water table in urban areas across the Nation. Although contaminants were detected less frequently in deeper ground water typically developed for public supply the proximity of contaminant mixtures to underlying public-water-supply sources prompted the NAWQA Program to begin, in 2001, an intensive study to assess the vulnerability of public-supply wells to contamination. As part of this study, the pathways and processes by which contaminants reach public-supply wells in nine aquifer systems across the country are being investigated. In addition to studying the processes that occur below land surface—whereby contaminants are mobilized or attenuated—scientists are also investigating how human activities can affect the vulnerability of public-supply wells to contamination. This fact sheet highlights findings from two reports on the vulnerability study of a single, representative public-supply well in York, Nebraska. The selected high-capacity well typically produces more than 720,000 gallons per day from the upper confined aquifer of the High Plains aquifer. A possible source of contamination to the well is intensive, irrigated agriculture, which can sometimes result in elevated concentrations of nitrate and pesticides in ground water. In addition, a sampling of the selected public-supply well by the USGS in 2002 found low concentrations of the solvents trichloroethylene (TCE), tetrachloroethylene (PCE), and their degradation products, which may be linked to historical chemical use in urban and residential areas of York. Uranium and arsenic (which occur naturally in the sediments that make up the aquifers in the area) also were detected in 2002 at concentrations less than drinking-water standards but still of concern. Overall, the current NAWQA study found that three primary factors affect the movement and fate of contaminants and the vulnerability of the public-supply well in York: (1) timing of water entry (recharge) to the aquifer, (2) short-circuiting of natural flow paths through inactive wells, and (3) natural geochemical conditions of the aquifer. Study findings are intended to help water managers, drinking-water suppliers, policymakers, and scientists to better understand how and why contamination of public-supply wells occurs and whether water quality may improve or degrade. Additionally, study findings may be used to evaluate various pumping, resource-development, and land-management scenarios.

  17. Final report on CCM key comparison CCM.D-K2: Comparison of liquid density standards

    NASA Astrophysics Data System (ADS)

    Bettin, Horst; Jacques, Claude; Zelenka, Zoltán; Fujii, Ken-ichi; Kuramoto, Naoki; Chang, Kyung-Ho; Lee, Yong Jae; Becerra, Luis Omar; Domostroeva, Natalia

    2013-01-01

    The results are presented of the key comparison CCM.D-K2 that covered the density measurements of four liquids: the density of water at 20 °C, of pentadecane at 15 °C, 20 °C, 40 °C and 60°C, of tetrachloroethlyene at 5 °C and 20 °C and of a viscous oil at 20 °C. Seven national metrology institutes measured the densities at atmospheric pressure by hydrostatic weighing of solid density standards in the time interval from 27 April 2004 to 28 June 2004. Since the participants were asked not to include components for a possible drift or inhomogeneity of the liquid in their uncertainty budget, these uncertainty contributions are investigated for the final evaluation of the data. For this purpose, results of stability and homogeneity measurements of the pilot laboratory are used. The participants decided not to include a possible drift of the liquid's density since no significant drift could be detected, and the influence of the drift and its uncertainty are negligible. Similarly, the inhomogeneity of the water and pentadecane samples is not significant and has no influence on the evaluation. Thus, it was neglected. Only the inhomogeneities of tetrachloroethylene and of the viscous oil were significant. Consequently, they were included in the evaluation. With one or two exceptions, the results show good agreement among the participants. Only in the case of water are the results clearly discrepant. The key comparison reference values were calculated by the weighted mean (taking into account a small correlation between two participants) in the case of consistent results. Otherwise the Procedure B of Cox was used. The expanded uncertainties of all reference densities are below 1 × 10-5 in relative terms. This satisfies the needs of all customers who wish to calibrate or check liquid density measuring instruments such as oscillation-type density meters. The comparison fully supports the calibration measurement capabilities table in the BIPM key comparison database. The results can be used to link regional comparisons to this CCM key comparison. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  18. GE/NOMADICS IN-WELL MONITORING SYSTEM FOR VERTICAL PROFILING OF DNAPL CONTAMINANTS

    SciTech Connect

    Ronald E. Shaffer; Radislav Potyralio; Joseph Salvo; Timothy Sivavec; Lloyd Salsman

    2003-04-01

    This report describes the Phase I effort to develop an Automated In Well Monitoring System (AIMS) for in situ detection of chlorinated volatile organic compounds such as trichloroethylene (TCE) and tetrachloroethylene (PCE) in groundwater. AIMS is composed of 3 primary components: (a) sensor probe, (b) instrument delivery system, and (c) communication/recharging station. The sensor probe utilizes an array of thickness shear mode (TSM) sensors coated with chemically-sensitive polymer films provides a low-cost, highly sensitive microsensor platform for detection and quantification. The instrument delivery system is used to position the sensor probe in 2 inch or larger groundwater monitoring wells. A communication/recharging station provides wireless battery recharging and communication to enable a fully automated system. A calibration curve for TCE in water was built using data collected in the laboratory. The detection limit of the sensor probe was 6.7 ppb ({micro}g/L) for TCE in water. A preliminary field test was conducted at a GE remediation location and a pilot field test was performed at the DOE Savannah River Site (SRS). The AIMS system was demonstrated in an uncontaminated (i.e., ''clean'') 2-inch well and in a 4-inch well containing 163.5 ppb of TCE. Repeat measurements at the two wells indicated excellent day-to-day reproducibility. Significant differences in the sensor responses were noted between the two types of wells but they did not closely match the laboratory calibration data. The robustness of the system presented numerous challenges for field work and limited the scope of the SRS pilot field test. However, the unique combination of trace detection (detection limits near the MCL, minimum concentration level) and size (operations in 2-inch or larger groundwater wells) is demonstration of the promise of this technology for long-term monitoring (LTM) applications or rapid site characterization. Using the lessons learned from the pilot field test, a number of design changes are proposed to increase the robustness of the system for extended field studies and commercialization.

  19. Design and Operation of a Borehole Straddle Packer for Ground-Water Sampling and Hydraulic Testing of Discrete Intervals at U.S. Air Force Plant 6, Marietta, Georgia

    USGS Publications Warehouse

    Holloway, Owen G.; Waddell, Jonathan P.

    2008-01-01

    A borehole straddle packer was developed and tested by the U.S. Geological Survey to characterize the vertical distribution of contaminants, head, and hydraulic properties in open-borehole wells as part of an ongoing investigation of ground-water contamination at U.S. Air Force Plant 6 (AFP6) in Marietta, Georgia. To better understand contaminant fate and transport in a crystalline bedrock setting and to support remedial activities at AFP6, numerous wells have been constructed that include long open-hole intervals in the crystalline bedrock. These wells can include several discontinuities that produce water, which may contain contaminants. Because of the complexity of ground-water flow and contaminant movement in the crystalline bedrock, it is important to characterize the hydraulic and water-quality characteristics of discrete intervals in these wells. The straddle packer facilitates ground-water sampling and hydraulic testing of discrete intervals, and delivery of fluids including tracer suites and remedial agents into these discontinuities. The straddle packer consists of two inflatable packers, a dual-pump system, a pressure-sensing system, and an aqueous injection system. Tests were conducted to assess the accuracy of the pressure-sensing systems, and water samples were collected for analysis of volatile organic compound (VOCs) concentrations. Pressure-transducer readings matched computed water-column height, with a coefficient of determination of greater than 0.99. The straddle packer incorporates both an air-driven piston pump and a variable-frequency, electronic, submersible pump. Only slight differences were observed between VOC concentrations in samples collected using the two different types of sampling pumps during two sampling events in July and August 2005. A test conducted to assess the effect of stagnation on VOC concentrations in water trapped in the system's pump-tubing reel showed that concentrations were not affected. A comparison was conducted to assess differences between three water-sampling methods - collecting samples from the well by pumping a packer-isolated zone using a submersible pump, by using a grab sampler, and by using a passive diffusion sampler. Concentrations of tetrachloroethylene, trichloroethylene and 1,2-dichloropropane were greatest for samples collected using the submersible pump in the packed-isolated interval, suggesting that the straddle packer yielded the least dilute sample.

  20. Induced Polarization with Electromagnetic Coupling: 3D Spectral Imaging Theory, EMSP Project No. 73836

    SciTech Connect

    Morgan, F. Dale; Sogade, John

    2004-12-14

    This project was designed as a broad foundational study of spectral induced polarization (SIP) for characterization of contaminated sites. It encompassed laboratory studies of the effects of chemistry on induced polarization, development of 3D forward modeling and inversion codes, and investigations of inductive and capacitive coupling problems. In the laboratory part of the project a physico-chemical model developed in this project was used to invert laboratory IP spectra for the grain size and the effective grain size distribution of the sedimentary rocks as well as the formation factor, porosity, specific surface area, and the apparent fractal dimension. Furthermore, it was established that the IP response changed with the solution chemistry, the concentration of a given solution chemistry, valence of the constituent ions, and ionic radius. In the field part of the project, a 3D complex forward and inverse model was developed. It was used to process data acquired at two frequencies (1/16 Hz and 1/ 4Hz) in a cross-borehole configuration at the A-14 outfall area of the Savannah River Site (SRS) during March 2003 and June 2004. The chosen SRS site was contaminated with Tetrachloroethylene (TCE) and Trichloroethylene (PCE) that were disposed in this area for several decades till the 1980s. The imaginary conductivity produced from the inverted 2003 data correlated very well with the log10 (PCE) concentration derived from point sampling at 1 ft spacing in five ground-truth boreholes drilled after the data acquisition. The equivalent result for the 2004 data revealed that there were significant contaminant movements during the period March 2003 and June 2004, probably related to ground-truth activities and nearby remediation activities. Therefore SIP was successfully used to develop conceptual models of volume distributions of PCE/TCE contamination. In addition, the project developed non-polarizing electrodes that can be deployed in boreholes for years. A total of 28 of these electrodes were deployed at the SRS site in September of 2002. The project found that (1) currently available field instrumentation need to be faster by an order of magnitude for full SIP to be engaged for broadband characterization in the field, (2) some aspects of the capacitive coupling problem in borehole geometries can be solved by use of a high impedance receiver, (3) a careful investigation of ways to adequately compare inversion results to ground-truth data is warranted, (4) more laboratory studies should be directed to understand the influence of micro-organisms and long residence time of contaminants (aging) on spectral IP properties.

  1. Water-Quality Conditions of Chester Creek, Anchorage, Alaska, 1998-2001

    USGS Publications Warehouse

    Glass, Roy L.; Ourso, Robert T.

    2006-01-01

    Between October 1998 and September 2001, the U.S. Geological Survey's National Water-Quality Assessment Program evaluated the water-quality conditions of Chester Creek, a stream draining forest and urban settings in Anchorage, Alaska. Data collection included water, streambed sediments, lakebed sediments, and aquatic organisms samples from urban sites along the stream. Urban land use ranged from less than 1 percent of the basin above the furthest upstream site to 46 percent above the most downstream site. Findings suggest that water quality of Chester Creek declines in the downstream direction and as urbanization in the watershed increases. Water samples were collected monthly and during storms at a site near the stream's mouth (Chester Creek at Arctic Boulevard) and analyzed for major ions and nutrients. Water samples collected during water year 1999 were analyzed for selected pesticides and volatile organic compounds. Concentrations of fecal-indicator bacteria were determined monthly during calendar year 2000. During winter, spring, and summer, four water samples were collected at a site upstream of urban development (South Branch of South Fork Chester Creek at Tank Trail) and five from an intermediate site (South Branch of South Fork Chester Creek at Boniface Parkway). Concentrations of calcium, magnesium, sodium, chloride, and sulfate in water increased in the downstream direction. Nitrate concentrations were similar at the three sites and all were less than the drinking-water standard. About one-quarter of the samples from the Arctic Boulevard site had concentrations of phosphorus that exceeded the U.S. Environmental Protection Agency (USEPA) guideline for preventing nuisance plant growth. Water samples collected at the Arctic Boulevard site contained concentrations of the insecticide carbaryl that exceeded the guideline for protecting aquatic life. Every water sample revealed a low concentration of volatile organic compounds, including benzene, toluene, tetrachloroethylene, methyl tert-butyl ether, and chloroform. No water samples contained volatile organic compounds concentrations that exceeded any USEPA drinking-water standard or guideline. Fecal-indicator bacteria concentrations in water from the Arctic Boulevard site commonly exceeded Federal and State guidelines for water-contact recreation. Concentrations of cadmium, copper, lead, and zinc in streambed sediments increased in the downstream direction. Some concentrations of arsenic, chromium, lead, and zinc in sediments were at levels that can adversely affect aquatic organisms. Analysis of sediment chemistry in successive lakebed-sediment layers from Westchester Lagoon near the stream's mouth provided a record of water-quality trends since about 1970. Concentrations of lead have decreased from peak levels in the mid-1970s, most likely because of removing lead from gasoline and lower lead content in other products. However, concen-trations in recently-deposited lakebed sediments are still about 10 times greater than measured in streambed sediments at the upstream Tank Trail site. Zinc concentrations in lakebed sediments also increased in the early 1970s to levels that exceeded guidelines to protect aquatic life and have remained at elevated but variable levels. Pyrene, benz[a]anthracene, and phenanthrene in lakebed sediments also have varied in concentrations and have exceeded protection guidelines for aquatic life since the 1970s. Concentrations of dichloro-diphenyl-trichloroethane, polychlorinated biphenyls (PCBs), or their by-products generally were highest in lakebed sediments deposited in the 1970s. More recent sediments have concentrations that vary widely and do not show distinct temporal trends. Tissue samples of whole slimy sculpin (Cottus cognatus), a non-migratory species of fish, showed con-centrations of trace elements and organic contaminants. Of the constituents analyzed, only selenium concentra-tions showed levels of potential concern for

  2. Water quality of the Mississippian carbonate aquifer in parts of middle Tennessee and northern Alabama, 1999

    USGS Publications Warehouse

    Kingsbury, James A.; Shelton, John M.

    2002-01-01

    Water-quality data for nitrate, fecal-indicator bacteria, pesticides, and volatile organic compounds collected in parts of Middle Tennessee and northern Alabama indicate that the Mississippian carbonate aquifer in these areas is susceptible to contamination from point and nonpoint sources. Thirty randomly located wells (predominantly domestic), two springs, and two additional public-supply wells were sampled in the summer of 1999 as part of the U.S. Geological Survey?s National Water-Quality Assessment (NAWQA) Program. These wells and springs were sampled to characterize the occurrence and distribution of the above constituents in this karst aquifer of Mississippian age and to determine the principal environmental factors related to their occurrence.Nitrate and fecal indicator bacteria were frequently detected at the sampled sites. Nitrate exceeded the drinking-water maximum contaminant level of 10 milligrams per liter in two samples; the median concentration for all samples was about 1.5 milligrams per liter. Correlation of nitrate concentrations to the amount of cropland near a site and to pesticide detections indicates that fertilizer application is the predominant source of nitrogen to the aquifer. Fecal-indicator bacteria were present in samples from about 40 percent of the sites. The presence of fecal-indicator bacteria is weakly correlated to the depth to ground water but is not correlated to a specific land use near the sites.Pesticides and pesticide breakdown products (metabolites) were detected at 74 percent of the sites sampled. Concentrations generally were less than 1 microgram per liter and no pesticide detections exceeded drinking-water maximum contaminant levels. The maximum total pesticide concentration measured was about 4 micrograms per liter. Intensity of pesticide use, proximity of sites to areas of pesticide application, and soil hydrologic group were the primary factors affecting the occurrence of pesticides.Volatile organic compounds were detected at generally low concentrations at about 81 percent of the sites sampled. Concentrations of trichloroethylene, tetrachloroethylene, and 1,2-dichloropropane at three sites equalled or exceeded drinking-water maximum contaminant levels. The maximum concentration measured was 7.5 micrograms per liter of trichloroethylene. The presence of volatile organic compounds in the Mississippian carbonate aquifer was not related to hydrogeology, soil properties, or land use near the sites; although higher total volatile organic compound concentrations and greater numbers of compounds in samples generally were associated with a higher percentage of urban land use near a site. Chloroform was the most frequently detected compound, and correlation of low-level detections to the amount of wetlands near sites having these detections may indicate biogenic formation of chloroform.The relation between land use and water quality was stronger for constituents that are contributed to the environment systematically (fertilizer and pesticide applications), than those contributed inadvertently (leaking septic tanks or chemical spills or leaks). Land use and soils characterized in circular buffer areas near sites sampled in this karst aquifer explained some of the variation in nitrate concentration and presence of pesticides. Use of land use and soil data with greater detail than the large scale data used in this analysis and buffer areas based on well capacities and ground-water withdrawals might strengthen this type of analysis.

  3. Nonaqueous Phase Liquid Dissolution in Porous Media: Multi-Scale Effects of Multi-Component Dissolution Kinetics on Cleanup Time

    SciTech Connect

    McNab, W; Ezzedine, S; Detwiler, R

    2007-02-26

    Industrial organic solvents such as trichloroethylene (TCE) and tetrachloroethylene (PCE) constitute a principal class of groundwater contaminants. Cleanup of groundwater plume source areas associated with these compounds is problematic, in part, because the compounds often exist in the subsurface as dense nonaqueous phase liquids (DNAPLs). Ganglia (or 'blobs') of DNAPL serve as persistent sources of contaminants that are difficult to locate and remediate (e.g. Fenwick and Blunt, 1998). Current understanding of the physical and chemical processes associated with dissolution of DNAPLs in the subsurface is incomplete and yet is critical for evaluating long-term behavior of contaminant migration, groundwater cleanup, and the efficacy of source area cleanup technologies. As such, a goal of this project has been to contribute to this critical understanding by investigating the multi-phase, multi-component physics of DNAPL dissolution using state-of-the-art experimental and computational techniques. Through this research, we have explored efficient and accurate conceptual and numerical models for source area contaminant transport that can be used to better inform the modeling of source area contaminants, including those at the LLNL Superfund sites, to re-evaluate existing remediation technologies, and to inspire or develop new remediation strategies. The problem of DNAPL dissolution in natural porous media must be viewed in the context of several scales (Khachikian and Harmon, 2000), including the microscopic level at which capillary forces, viscous forces, and gravity/buoyancy forces are manifested at the scale of individual pores (Wilson and Conrad, 1984; Chatzis et al., 1988), the mesoscale where dissolution rates are strongly influenced by the local hydrodynamics, and the field-scale. Historically, the physico-chemical processes associated with DNAPL dissolution have been addressed through the use of lumped mass transfer coefficients which attempt to quantify the dissolution rate in response to local dissolved-phase concentrations distributed across the source area using a volume-averaging approach (Figure 1). The fundamental problem with the lumped mass transfer parameter is that its value is typically derived empirically through column-scale experiments that combine the effects of pore-scale flow, diffusion, and pore-scale geometry in a manner that does not provide a robust theoretical basis for upscaling. In our view, upscaling processes from the pore-scale to the field-scale requires new computational approaches (Held and Celia, 2001) that are directly linked to experimental studies of dissolution at the pore scale. As such, our investigation has been multi-pronged, combining theory, experiments, numerical modeling, new data analysis approaches, and a synthesis of previous studies (e.g. Glass et al, 2001; Keller et al., 2002) aimed at quantifying how the mechanisms controlling dissolution at the pore-scale control the long-term dissolution of source areas at larger scales.

  4. Results of the basewide monitoring program at Wright-Patterson Air Force Base, Ohio, 1993-1994

    USGS Publications Warehouse

    Schalk, C.W.; Cunningham, W.L.

    1996-01-01

    Geologic and hydrologic data were collected at Wright-Patterson Air Force Base (WPAFB), Ohio, as part of Basewide Monitoring Program (BMP) that began in 1992. The BMP was designed as a long-term project to character ground-water and surface-water quality (including streambed sediments), describe water-quality changes as water enters, flows across, and exits the Base, and investigate the effects of activities at WPAFB on regional water quality. Ground water, surface ware, and streambed sediment were sampled in four rounds between August 1993 and September 1994 to provide the analytical data needed to address the objectives of the BMP. Surface-water-sampling rounds were designed to include most of the seasonal hydrologic conditions encountered in southwestern Ohio, including baseflow conditions and spring runoff. Ground-water-sampling rounds were scheduled for times of recession and recharfe. Ground-water data were used to construct water-table, potentiometric, and vertical gradient maps of the WPAFB area. Water levels have not changed significantly since 1987, but the effects of pumping on and near the Base can have a marked effect on water levels in localized areas. Ground-ware gradients generally were downward throughout Area B (the southwestern third of the Base) and in the eastern third of Areas A and C (the northeastern two-thirds of the Base), and were upward in the vicinity of Mad River. Stream-discharge measurements verified these gradients. Many of the U.S. Environmental Protection Agency maximum contaminant level (MCL) exceedances of inorganic constituents in ground water were associated with water from the bedrock. Exceedances of concentrations of chromium and nickel were found consistently in five wells completed in the glacial aquifer beneath the Base. Five organic compounds [trichloroethylene (TCE), tetrachloroethylene (PCE), vinyl chloride, benzene, and bis(2-ethylhexyl) phthalate] were detected at concentrations that exceeded MCLs; all of the TCE, PCE, and vinyl chloride exceedances were in water from glacial aquifer, whereas the benzene exceedance and most of the bis(2-ethylhexyl) phthalate exceedances were in water from the bedrock. TCE (16 exceedances) and PCE (11 exceedances) most frequently exceeded the MCLs and were detected in the most samples. A decrease in concentrations of inorganic and organic compounds with depth suggest that many constituents detected in ground-water samples are associated partly with human activities, in addition to their natural occurrence. Included in the list of these constituents are nickel, chromium, copper, lead vanadium, zinc, bromide, and nitrate. Many constituents are not found at depths greater than 60 to 80 feet, possibly indicating that human effects on ground-water quality are limited to shallow flow systems. Organic compounds detected in shallow or intermediate-depth wells were aligned mostly with flowpaths that pass through or near identified hazardous-waste sites. Few organic contaminants were detected in surface water. The only organic compound to exceed MCLs for drinking water was bis(2-ethylhexyl) phthalate, but it was detected at concentrations just above the MCL. Inorganic constituents detected at concentration exceeding MCLs include beryllium (twice), lead (once), thallium (once), and gross alpha radiation (once). No polycyclic aromatic (PAHs) were detected in surface-water samples. The highest concentrations of contaminants detected during a storm event were in samples from upgradient locations, indicating that off-Base sources may contribute to surface-water contamination. Inorganic and organic contaminants were found in streambed sediments at WPAFB, primarily in Areas A and C. Trace metals such as lead, mercury, arsenic, and cadmium were detected at 16 locations at concentrations considered 'elevated' according to a ranking scheme for sediments. PAHS were the organic compounds detected most frequently and in highest concentrations organo

  5. Geohydrology and distribution of volatile organic compounds in ground water in the Casey Village area, Bucks County, Pennsylvania

    USGS Publications Warehouse

    Sloto, Ronald A.; Conger, Randall W.; Grazul, Kevin E.

    1998-01-01

    Casey Village and the adjoining part of the U.S. Naval Air Warfare Center (NAWC) are underlain by the Late Triassic-age Stockton Formation, which consists of a dipping series of siltstones and sandstones. The direction of vertical ground-water gradients in the Stockton Formation varies among well locations and sometimes with time. Vertical gradients can be substantial; the difference in water levels at one well pair (two wells screened at different depths) was 7.1 ft (feet) over a 32-ft vertical section of the aquifer. Potentiometric-surface maps show a groundwater divide that bisects the Casey Village area. For wells screened between 18 and 64 ft below land surface (bls), the general ground-water gradient is to the east and northeast on the east side of the divide and to the south and southwest on the west side of the divide. For wells screened between 48 and 106 ft bls, the general ground-water gradient is to the northeast on the east side of the divide and to the southwest and northwest on the west side of the divide. An aquifer test at one well in Casey Village caused drawdown in wells on the opposite side of the ground-water divide on the NAWC and shifted the ground-water divide in the deeper potentiometric surface to the west. Drawdowns formed an elliptical pattern, which indicates anisotropy; however, anisotropy is not aligned with strike or dip. Hydraulic stress caused by pumping crosses stratigraphic boundaries. Between 1993 and 1996, the trichloroethylene (TCE) concentration in water samples collected from wells in Casey Village decreased. The highest concentration of TCE measured in water from one well decreased from 1,200 mg/L (micrograms per liter) in 1993 when domestic wells were pumped in Casey Village to 140 mg/L in 1996, 3 years after the installation of public water and the cessation of domestic pumping. This suggests that pumping of domestic wells may have contributed to TCE migration. Between 1993 and 1996, the tetrachloroethylene (PCE) concentration in water samples collected from wells in Casey Village decreased only slightly. The highest concentration of PCE measured in water from one well decreased from 720 mg/L in 1993 to 630 mg/L in 1996. The distribution of TCE and PCE in ground water indicates the presence of separate PCE and TCE plumes, each with a different source area. The TCE plume appears to be moving in two directions away from the ground-water divide area. The pumping of a domestic well may have caused TCE migration into the ground-water divide area. From the divide area, the TCE plume appears to be moving both to the east and the west under the natural hydraulic gradient. Aquifer-isolation tests conducted in the well with the highest TCE concentrations showed that concentrations of TCE in water samples from the isolated intervals were similar but slightly lower in the deeper isolated zones than in the shallower isolated zones. Upward flow was measured in this well during geophysical logging. If the source of TCE to the well was from shallow fractures, upward flow of less contaminated water could be flushing TCE from the immediate vicinity of this well. This may help explain why the concentration of TCE in water from this well decreased an order of magnitude between 1993 and 1996.

  6. Assessing the susceptibility to contamination of two aquifer systems used for public water supply in the Modesto and Fresno metropolitan areas, California, 2001 and 2002

    USGS Publications Warehouse

    Wright, Michael T.; Belitz, Kenneth; Johnson, Tyler

    2004-01-01

    Ground-water samples were collected from 90 active public supply wells in the Fresno and Modesto metropolitan areas as part of the California Aquifer Susceptibility (CAS) program. The CAS program was formed to examine the susceptibility to contamination of aquifers that are tapped by public supply wells to serve the citizens of California. The objectives of the program are twofold: (1) to evaluate the quality of ground water used for public supply using volatile organic compound (VOC) concentrations in ground-water samples and (2) to determine if the occurrence and distribution of low level VOCs in ground water and characteristics, such as land use, can be used to predict aquifer susceptibility to contamination from anthropogenic activities occurring at, or near, land surface. An evaluation was made of the relation between VOC occurrence and the explanatory variables: depth to the top of the uppermost well perforation, land use, relative ground-water age, high nitrate concentrations, density of leaking underground fuel tanks (LUFT), and source of recharge water. VOCs were detected in 92 percent of the wells sampled in Modesto and in 72 percent of the wells sampled in Fresno. Trihalomethanes (THM) and solvents were frequently detected in both study areas. Conversely, the gasoline components?benzene, toluene ethylbenzene, and xylenes (BTEX)?were rarely, if at all, detected, even though LUFTs were scattered throughout both study areas. The rare occurrence of BTEX compounds may be the result of their low solubility and labile nature in the subsurface environment. Samples were analyzed for 85 VOCs; 25 were detected in at least one sample. The concentrations of nearly all VOCs detected were at least an order of magnitude below action levels set by drinking water standards. Concentrations of four VOCs exceeded federal and state maximum contaminant levels (MCL): the solvent trichloroethylene (TCE) and the fumigant 1, 2-dibromo-3-chloropropane (DBCP) in Fresno, and the solvents TCE and tetrachloroethylene (PCE) in Modesto. Chloroform, which is a by product of water disinfection and a constituent used in industrial processes since the 1920s, was the most frequently detected compound, whereas the gasoline oxygenate methyl tert-butyl ether (MTBE), which has been in widespread production and use only since the 1990s, was detected in only 2 percent of the samples. Downward migration of contaminants appears to be a viable pathway of contamination in the unconfined and semi-confined aquifers underlying the Fresno and Modesto study areas. Within the individual study areas, VOCs were detected more frequently and in greater numbers in shallower wells than in deeper wells. Additionally, VOCs were detected more frequently and in greater numbers in Modesto than in Fresno. Wells sampled in Modesto were significantly shallower than the wells sampled in Fresno; the other explanatory variables examined in this report were not significantly different between the two study areas. VOCs occurred more frequently in younger ground water (water recharged after 1952) than in older ground water (water recharged prior to 1952). Additionally, wells withdrawing younger ground water had a higher number of VOCs detected per well than did wells withdrawing older ground water. Younger ground water was at or near the land surface during a period when VOCs came into widespread production and use. Therefore, wells from which younger ground water is withdrawn may be more susceptible to contamination. Of the explanatory variables examined in this study, land use was the best predictor of aquifer susceptibility in the Fresno and Modesto study areas. VOCs were detected more frequently in wells located in heavily urbanized areas. The number of VOCs detected in ground water was positively correlated to the degree of urbanization. VOCs are produced and used primarily in urban land use settings; therefore, aquifers underlying urban areas may be more susceptible to

  7. Hydrogeology, Chemical Characteristics, and Transport Processes in the Zone of Contribution of a Public-Supply Well in York, Nebraska

    USGS Publications Warehouse

    Landon, Matthew K.; Clark, Brian R.; McMahon, Peter B.; McGuire, Virginia L.; Turco, Michael J.

    2008-01-01

    In 2001, the U.S. Geological Survey, as part of the National Water Quality Assessment (NAWQA) Program, initiated a topical study of Transport of Anthropogenic and Natural Contaminants (TANC) to PSW (public-supply wells). Local-scale and regional-scale TANC study areas were delineated within selected NAWQA study units for intensive study of processes effecting transport of contaminants to PSWs. This report describes results from a local-scale TANC study area at York, Nebraska, within the High Plains aquifer, including the hydrogeology and geochemistry of a 108-square-kilometer study area that contains the zone of contribution to a PSW selected for study (study PSW), and describes factors controlling the transport of selected anthropogenic and natural contaminants to PSWs. Within the local-scale TANC study area, the High Plains aquifer is approximately 75 m (meter) thick, and includes an unconfined aquifer, an upper confining unit, an upper confined aquifer, and a lower confining unit with lower confined sand lenses (units below the upper confining unit are referred to as confined aquifers) in unconsolidated alluvial and glacial deposits overlain by loess and underlain by Cretaceous shale. From northwest to southeast, land use in the local-scale TANC study area changes from predominantly irrigated agricultural land to residential and commercial land in the small community of York (population approximately 8,100). For the purposes of comparing water chemistry, wells were classified by degree of aquifer confinement (unconfined and confined), depth in the unconfined aquifer (shallow and deep), land use (urban and agricultural), and extent of mixing in wells in the confined aquifer with water from the unconfined aquifer (mixed and unmixed). Oxygen (delta 18O) and hydrogen (delta D) stable isotopic values indicated a clear isotopic contrast between shallow wells in the unconfined aquifer (hereinafter, unconfined shallow wells) and most monitoring wells in the confined aquifers (hereinafter, confined unmixed wells). Delta 18O and delta D values for a minority of wells in the confined aquifers were intermediate between those for the unconfined shallow wells and those for the confined unmixed wells. These intermediate values were consistent with mixing of water from unconfined and confined aquifers (hereinafter, confined mixed wells). Oxidation-reduction conditions were primarily oxic in the unconfined aquifer and variably reducing in the confined aquifers. Trace amounts of volatile organic compounds (VOC), particularly tetrachloroethylene (PCE) and trichloroethylene (TCE), were widely detected in unconfined shallow urban wells and indicated the presence of young urban recharge waters in most confined mixed wells. The presence of degradation products of agricultural pesticides (acetochlor and alachlor) in some confined mixed wells suggests that some fraction of the water in these wells also was the result of recharge in agricultural areas. In the unconfined aquifer, age-tracer data (chlorofluorocarbon and sulfur hexafluoride data, and tritium to helium-3 ratios) fit a piston-flow model, with apparent recharge ages ranging from 7 to 48 years and generally increasing with depth. Age-tracer data for the confined aquifers were consistent with mixing of 'old' water, not containing modern tracers recharged in the last 60 years, and exponentially-mixed 'young' water with modern tracers. Confined unmixed wells contained less than (=) 97% of old water. Confined mixed wells contained >30% young water and mean ages ranged from 12 to 14 years. Median concentrations of nitrate (as nitrogen, hereinafter, nitrate-N) were 17.3 and 16.0 mg/L (milligram per liter) in unconfined shallow urban and agricultural wells, respectively, indicating a range of likely nitrate sources. Septic systems are most numerous near the edge of the urban area and appear to be

  8. Hydrogeologic Investigation, Water Chemistry Analysis, and Model Delineation of contributing Areas for City of Tallahassee Public-Supply Wells, Tallahassee, Florida

    USGS Publications Warehouse

    Davis, J. Hal; Katz, Brian G.

    2007-01-01

    Ground water from the Upper Floridan aquifer is the sole source of water supply for Tallahassee, Florida, and the surrounding area. The City of Tallahassee (the City) currently operates 28 water-supply wells; 26 wells are distributed throughout the City and 2 are located in Woodville, Florida. Most of these wells yield an ample supply of potable water; however, water from several wells has low levels of tetrachloroethylene (PCE). The City removes the PCE from the water by passing it through granular-activated carbon units before distribution. To ensure that water-supply wells presently free of contamination remain clean, it is necessary to understand the ground-water flow system in sufficient detail to protect the contributing areas. Ground-water samples collected from four public-supply wells were analyzed for tritium (3H), chlorofluorocarbons (CFCs), and sulfur hexafluoride (SF6). Using data for the CFC compounds, apparent ground-water ages ranged from 7 to 31 years. For SF6, the apparent ages tended to be about 5 to 10 years younger than those from CFCs. Apparent ages based on the tritium/tritiogenic helium-3 (3H/3Hetrit) method ranged from 26 to 33 years. The three dating methods indicate that the apparent age of ground water generally decreases from northern to southern Leon County. This southward trend of decreasing ages is consistent with increasing amounts of recharge that occur as ground water moves from north to south. The ground-water age data derived by geochemical and tracer analyses were used in combination with the flow model and particle tracking to determine an effective porosity for the Hawthorn clays and Upper Floridan aquifer. The effective porosities for the Upper Floridan aquifer that resulted in best model matches were averaged to produce an effective porosity of 7 percent, and the effective porosities for the Hawthorn clays that resulted in a match were averaged to produce an effective porosity of 22 percent. Probabilistic contributing areas were determined for 26 City wells using MODFLOW and MODPATH. For each probabilistic contributing area delineated, the model was run 100 times and the results were analyzed statistically. For each of the 100 runs, a different hydraulic conductivity for each of the zones was assigned to the Upper Floridan aquifer. The hydraulic conductivities were generated randomly assuming a lognormal probability distribution; the mean of the distribution was equal to the hydraulic conductivity from the calibrated model. The 5-year time-dependent capture zones (TDCZs), assuming effective porosities of 0.1, 1, and 7 percent for four representative wells, were delineated. The higher probabilities of capture (greater than 40, 60, and 80 percent) were similar for all effective porosities, and the TDCZ delineated using a 7-percent porosity was slightly smaller; the lower probabilities of capture (greater than 10 and 20 percent) showed a large range of variability.

  9. Geohydrology and simulation of ground-water flow in the Red Clay Creek Basin, Chester County, Pennsylvania, and New Castle County, Delaware

    USGS Publications Warehouse

    Vogel, K.L.; Reif, A.G.

    1993-01-01

    The 54-square-mile Red Clay Creek Basin, located in the lower Delaware River Basin, is underlain primarily by metamorphic rocks that range from Precambrian to Lower Paleozoic in age. Ground water flows through secondary openings in fractured crystalline rock and through primary openings below the water table in the overlying saprolite. Secondary porosity and permeability vary with hydrogeologic unit, topographic setting, and depth. Thirty-nine percent of the water-bearing zones are encountered within 100 feet of the land surface, and 79 percent are within 200 feet. The fractured crystalline rock and overlying saprolite act as a single aquifer under unconfined conditions. The water table is a subdued replica of the land surface. Local ground-water flow systems predominate in the basin, and natural ground-water discharge is to streams, comprising 62 to 71 percent of streamflow. Water budgets for 1988-90 for the 45-square-mile effective drainage area above the Woodale, Del., streamflow-measurement station show that annual precipitation ranged from 43.59 to 59.14 inches and averaged 49.81 inches, annual streamflow ranged from 15.35 to 26.33 inches and averaged 20.24 inches, and annual evapotranspiration ranged from 27.87 to 30.43 inches and averaged 28.98 inches. The crystalline rocks of the Red Clay Creek Basin were simulated two-dimensionally as a single aquifer under unconfined conditions. The model was calibrated for short-term steady-state conditions on November 2, 1990. Recharge was 8.32 inches per year. Values of aquifer hydraulic conductivity in hillside topographic settings ranged from 0.07 to 2.60 feet per day. Values of streambed hydraulic conductivity ranged from 0.08 to 26.0 feet per day. Prior to simulations where ground-water development was increased, the calibrated steady-state model was modified to approximate long-term average conditions in the basin. Base flow of 11.98 inches per year and a ground-water evapotranspiration rate of 2.17 inches per year were simulated by the model. Different combinations of ground-water supply and wastewater-disposal plans were simulated to assess their effects on the stream-aquifer system. Six of the simulations represent an increase in population of 14,283 and water use of 1.07 million gallons per day. One simulation represents an increase in population of 28,566 and water use of 2.14 million gallons per day. Reduction of average base flow is greatest for development plans with wastewater removed from the basin through sewers and is proportional to the amount of water removed from the basin. The development plan that had the least effect on water levels and base flow included on-lot wells and on-lot septic systems. Five organochlorine insecticides--lindane, DDT, dieldrin, heptachlor, and methoxychlor--were detected in ground water. Four organophosphorus insecticides--malathion, parathion, diazinon, and phorate--were detected in ground water. Four volatile organic compounds--benzene, toluene, tetrachloroethylene, and trichloroethylene--were detected in ground water. Phenol was detected at concentrations up to 8 micrograms per liter in water from 50 percent of 14 wells sampled. The concentration of dissolved nitrate in water from 18 percent of wells sampled exceeded 10 milligrams per liter as nitrogen; concentration of nitrate were as high as 19 milligrams per liter. PCB was detected in the bottom material of West Branch Red Clay Creek at Kennet Square at concentrations up to 5,600 micrograms per kilogram.

  10. Hanford Site Groundwater Monitoring for Fiscal Year 1998

    SciTech Connect

    Hartman, M.J. [and others

    1999-03-24

    This report presents the results of groundwater and vadose-zone monitoring and remediation for fiscal year (FY) 1998 on the Word Site, Washington. Soil-vapor extraction in the 200-West Area removed 777 kg of carbon tetrachloride in FY 1998, for a total of 75,490 kg removed since remediation began in 1992. Spectral gamma logging and evaluation of historical gross gamma logs near tank farms and liquid-disposal sites in the 200 Areas provided information on movement of contaminants in the vadose zone. Water-level monitoring was performed to evaluate groundwater-flow directions, to track changes in water levels, and to relate such changes to evolving disposal practices. Water levels over most of the Hanford Site continued to decline between June 1997 and June 1998. The most widespread radiological contaminant plumes in groundwater were tritium and iodine-129. Concentrations of technetium-99, uranium, strontium-90, and carbon-14 also exceeded drinking water standards in smaller plumes. Plutonium and cesium-137 exceeded standards only near the 216-B-5 injection well. Derived concentration guide levels specified in U.S. Department of Energy Order 5400.5 were exceeded for tritium, uranium, strontium-90, and plutonium in small plumes or single wells. One well completed in the basalt-confined aquifer beneath the 200-East Area exceeded the drinking water standard for technetium-99. Nitrate is the most extensive chemical contaminant. Carbon tetrachloride, chloroform, chromium, cis-l, Z-dichloroethylene, fluoride, and trichloroethylene also were present in smaller areas at levels above their maximum contaminant levels. Cyanide concentrations were elevated in one area but were below the maximum contaminant level. Tetrachloroethylene exceeded its maximum contaminant level in several wells in the 300 Area for the first time since the 1980s. Metals such as aluminum, cadmium, iron, manganese, and nickel exceeded their maximum contaminant levels in filtered samples from numerous wells; they are believed to represent natural components of groundwater. Resource Conservation and Recovery Act of 1976 groundwater monitoring continued at 25 waste management areas during FY 1998: 17 under detection programs and data indicate that they are not adversely affecting groundwater, 6 under interim-status groundwater-quality-assessment programs to assess possible contamination, and 2 under final-status corrective-action programs. Groundwater remediation in the 100 Areas continued to reduce the amount of strontium-90 (100-N) and chromium (100-K, D, and H) reaching the Columbia River. Two systems in the 200-West Area operated to prevent the spread of carbon tetrachloride and technetide uranium plumes. Groundwater monitoring continued at these sites and at other sites where there is no active remediation. A three-dimensional, numerical groundwater model was applied to simulate radionuclide movement from sources in the 200 Areas following site closure in 2050. Contaminants will continue to move toward the southeast and north (through Gable Gap), but the areas with levels exceeding drinking water standards will diminish.

  11. Modeling of a supersonic DC plasma torch system for carbon nanotube production

    NASA Astrophysics Data System (ADS)

    Guo, Liping

    The carbon nanotube (CNT) structure forms a very promising source material. It has unique properties such as high thermal and electrical conductivities, and a very high mechanical strength. In recent years, researchers were able to improve both the quantity and quality of the CNT production. Among the efforts made to scale up the production, Harbec and Meunier designed a new plasma torch process for the industrial production of CNT in bulk powder form. Their process is based on the DC plasma-jet pyrolysis of a carbon-containing gas. Experiments were conducted using either 100 slpm of argon or 225 slpm of helium. Tetrachloroethylene (C2Cl4, or TCE) was selected as the carbon raw material. The present work focuses on the modeling of this CNT synthesis process and aims at an understanding of the physical and chemical phenomena observed in this system. First, a description is made of the temperature and flow fields, as well as the species concentration distribution in the torch nozzle using both possibilities of He or Ar as the plasma gas. This is followed in the second part of the thesis by a model aimed to study the nucleation and evolution of the metal particles acting as catalyst for CNT growth in the nozzle. In the third part, the modeling of the TCE pyrolysis process in the flow was carried out. The fluid dynamics equations are used in this system showing supersonic characteristics. A realizable k-? model is used to address the turbulent effects in the flow fields. The moment method is employed to calculate the formation of the fine catalyst particles from the metal vapor injected. Within the supersonic domain of the flow field, the influence of existing shock waves on the particle nucleation is discussed, as well as the chemical reactions involved. Results show that the supersonic phenomena make it possible for metal particles to nucleate and be maintained in small sizes. This however also causes a backflow in the nozzle, which partially contributes to the experimentally observed soot deposition and CNT growth within the nozzle. The carbon containing gas experiences a fast dissociation process once it enters the nozzle. The produced carbon species are maintained in small clusters of carbon atoms in the high temperature environment within the nozzle. These clusters and atoms serve as the source of CNT growth and form a layer of carbon deposit on the surface of the nozzle. This deposited layer acts as a thermal insulator changing the conditions in the nozzle, particularly on the wall. A modeling of this effect is performed, confirming that the basic requirements for CNT growth are attained within the nozzle itself. A parametric study of the process is carried out and suggestions are made on the geometry of the reactor and the operating parameters for the formation of CNT. These modeling results suggest that the process can be optimized with carefully chosen operating parameters. With the specific design of the nozzle used here, it is recommended to operate at lower pressures in the reactor in order to avoid a backflow in the nozzle. Different kinds of metal catalyst can be used in this system and the reactor length should be adjusted accordingly in order to optimize the outcome of the process.

  12. California GAMA program: ground-water quality data in the San Diego drainages hydrogeologic province, California, 2004

    USGS Publications Warehouse

    Wright, Michael T.; Belitz, Kenneth; Burton, Carmen A.

    2005-01-01

    Because of concerns over ground-water quality, the California State Water Resources Control Board (SWRCB), in collaboration with the U.S. Geological Survey and Lawrence Livermore National Laboratory, has implemented the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. A primary objective of the program is to provide a current assessment of ground-water quality in areas where public supply wells are an important source of drinking water. The San Diego GAMA study unit was the first region of the state where an assessment of ground-water quality was implemented under the GAMA program. The San Diego GAMA study unit covers the entire San Diego Drainages hydrogeologic province, and is broken down into four distinct hydrogeologic study areas: the Temecula Valley study area, the Warner Valley study area, the Alluvial Basins study area, and the Hard Rock study area. A total of 58 ground-water samples were collected from public supply wells in the San Diego GAMA study unit: 19 wells were sampled in the Temecula Valley study area, 9 in the Warner Valley study area, 17 in the Alluvial Basins study area, and 13 in the Hard Rock study area. Over 350 chemical and microbial constituents and water-quality indicators were analyzed for in this study. However, only select wells were measured for all constituents and water-quality indicators. Results of analyses were calculated as detection frequencies by constituent classification and by individual constituents for the entire San Diego GAMA study unit and for the individual study areas. Additionally, concentrations of constituents that are routinely monitored were compared to maximum contaminant levels (MCL) and secondary maximum contaminant levels (SMCL). Concentrations of constituents classified as 'unregulated chemicals for which monitoring is required' (UCMR) were compared to the 'detection level for the purposes of reporting' (DLR). Eighteen of the 88 volatile organic compounds (VOCs) and gasoline oxygenates analyzed for were detected in ground-water samples. Twenty-eight wells sampled in the San Diego GAMA study had at least a single detection of VOCs or gasoline oxygenates. These constituents were most frequently detected in the Alluvial Basin study area (11 of 17 wells), and least frequently detected in the Warner Valley study area (one of nine wells). Trihalomethanes (THMs) were the most frequently detected class of VOCs (18 of 58 wells). The most frequently detected VOCs were chloroform (18 of 58 wells), bromodichloromethane (8 of 58 wells), and methyl tert-butyl ether (MTBE) (7 of 58 wells). Three VOCs were detected at concentrations greater than their MCLs. Tetrachloroethylene (PCE) and trichloroethylene (TCE) were detected in one well in the Hard Rock study area at concentrations of 9.75 and 7.27 micrograms per liter (?g/L), respectively; the MCL for these compounds is 5 ?g/L. MTBE was detected in one well in the Alluvial Basins study area at a concentration of 28.3 ?g/L; the MCL for MTBE is 13 ?g/L. Twenty-one of the 122 pesticides and pesticide degradates analyzed for were detected in ground-water samples. Pesticide or pesticide degradates were detected in 33 of 58 wells sampled, and were most frequently detected in the Temecula Valley study area wells (9 of 14 wells), and least frequently in the Warner Valley study area wells (3 of 9 wells). Herbicides were the most frequently detected class of pesticides (31 of 58 wells), and simazine was the most frequently detected compound (27 of 58 wells), followed by deethylatrazine (14 of 58 wells), prometon (10 of 58 wells), and atrazine (9 of 58 wells). None of the pesticides detected in ground-water samples had concentrations that exceeded MCLs. Eight waste-water indicator compounds were detected in ground-water samples. Twenty-one of 47 wells sampled for waste-water indicator compounds had at least a single detection. Waste-water indicator compounds were detected most frequently in the Allu

  13. Reactive hydro- end chlorocarbons in the troposphere and lower stratosphere : sources, distributions, and chemical impact

    NASA Astrophysics Data System (ADS)

    Scheeren, H. A.

    2003-09-01

    The work presented in this thesis focuses on measurements of chemical reactive C2 C7 non-methane hydrocarbons (NMHC) and C1 C2 chlorocarbons with atmospheric lifetimes of a few hours up to about a year. The group of reactive chlorocarbons includes the most abundant atmospheric species with large natural sources, which are chloromethane (CH3Cl), dichloromethane (CH2Cl2), and trichloromethane (CHCl3), and tetrachloroethylene (C2Cl4) with mainly anthropogenic sources. The NMHC and chlorocarbons are present at relatively low quantities in our atmosphere (10-12 10-9 mol mol-1 of air). Nevertheless, they play a key role in atmospheric photochemistry. For example, the oxidation of NMHC plays a dominant role in the formation of ozone in the troposphere, while the photolysis of chlorocarbons contributes to enhanced ozone depletion in the stratosphere. In spite of their important role, however, their global source and sinks budgets are still poorly understood. Hence, this study aims at improving our understanding of the sources, distribution, and chemical role of reactive NMHC and chlorocarbons in the troposphere and lower stratosphere. To meet this aim, a comprehensive data set of selected C2 C7 NMHC and chlorocarbons has been analyzed, derived from six aircraft measurement campaigns with two different jet aircrafts (the Dutch TUD/NLR Cessna Citation PH-LAB, and the German DLR Falcon) conducted between 1995 and 2001 (STREAM 1995 and 1997 and 1998, LBA-CLAIRE 1998, INDOEX 1999, MINOS 2001). The NMHC and chlorocarbons have been detected by gas-chromatography (GC-FID/ECD) in pre-concentrated whole air samples collected in stainless steel canister on-board the measurement aircrafts. The measurement locations include tropical (Maldives/Indian Ocean and Surinam), midlatitude (Western Europe and Canada) and polar regions (Lapland/northern Sweden) between the equator to about 70ºN, covering different seasons and pollution levels in the troposphere and lower stratosphere. Of special interest in this thesis are the tropical regions because they are becoming increasingly important in terms of global anthropogenic pollution and climate change. In addition, natural emissions of hydrocarbons (notably isoprene and terpenes from plants) and reactive chlorocarbons appear to be concentrated in the tropics, where the largest uncertainties exist with respect to source type and source strength. Whenever available, the reactive NMHC and chlorocarbon data have been analyzed with the help of concurrent measurements, which includes ozone (O3), carbon monoxide (CO), nitrogen oxide (NO), total reactive oxidized nitrogen (NOy), nitrous oxide (N2O), carbon dioxide (CO2), methane (CH4), acetone (CH3COCH3), methanol (CH3OH), acetonitrile (CH3CN), the chlorofluorocarbons CFC-11 (CCl3F) and CFC-12 (CCl2F2), the hydrofluorocarbon HFC-134a (CH2FCF3), and the hydrochlorofluorocarbons HCFC-141b (CH3CCl2F) and HCFC-142b (CH3CClF2). These additional measurements provided important information about the air mass origin, pollution sources, and chemical age of the encountered air masses. The STREAM-measurements contribute to the present understanding of the budgets of reactive organic trace species in the mid-latitude lower stratosphere at different seasonal conditions. It was found that during summer and fall, the mean concentrations of reactive NMHC and acetone in the lower stratosphere were a factor of two or more higher than during winter, as a result of more intense and frequent mixing across the tropopause. The role of tropical emissions in the global budget of hydrocarbons and the chlorocarbons CH3Cl, CH2Cl2, CHCl3, and C2Cl4 has been investigated during the LBA/CLAIRE 1998, INDOEX 1999 and MINOS 2001 campaigns. The INDOEX measurements over the Indian Ocean showed that strongly enhanced CH3Cl and related combustion tracers, such as CO, hydrocarbons and CH3CN in polluted air masses from India and Southeast Asia, relate to the extensive use of biofuels (notably the burning of agricultural waste and dung) in households and small industries. During the MINOS campaign

  14. Application of health-based screening levels to ground-water quality data in a state-scale pilot effort

    USGS Publications Warehouse

    Toccalino, Patricia L.; Norman, Julia E.; Phillips, Robyn H.; Kauffman, Leon J.; Stackelberg, Paul E.; Nowell, Lisa H.; Krietzman, Sandra J.; Post, Gloria B.

    2004-01-01

    A state-scale pilot effort was conducted to evaluate a Health-Based Screening Level (HBSL) approach developed for communicating findings from the U.S. Geological Survey (USGS) National Water-Quality Assessment Program in a human-health context. Many aquifers sampled by USGS are used as drinking-water sources, and water-quality conditions historically have been assessed by comparing measured contaminant concentrations to established drinking-water standards and guidelines. Because drinking-water standards and guidelines do not exist for many analyzed contaminants, HBSL values were developed collaboratively by the USGS, U.S. Environmental Protection Agency (USEPA), New Jersey Department of Environmental Protection, and Oregon Health & Science University, using USEPA toxicity values and USEPA Office of Water methodologies. The main objective of this report is to demonstrate the use of HBSL approach as a tool for communicating water-quality data in a human-health context by conducting a retrospective analysis of ground-water quality data from New Jersey. Another important objective is to provide guidance on the use and interpretation of HBSL values and other human-health benchmarks in the analyses of water-quality data in a human-health context. Ground-water samples collected during 1996-98 from 30 public-supply, 82 domestic, and 108 monitoring wells were analyzed for 97 pesticides and 85 volatile organic compounds (VOCs). The occurrence of individual pesticides and VOCs was evaluated in a human-health context by calculating Benchmark Quotients (BQs), defined as ratios of measured concentrations of regulated compounds (that is, compounds with Federal or state drinking-water standards) to Maximum Contaminant Level (MCL) values and ratios of measured concentrations of unregulated compounds to HBSL values. Contaminants were identified as being of potential human-health concern if maximum detected concentrations were within a factor of 10 of the associated MCL or HBSL (that is, maximum BQ value (BQmax) greater than or equal to 0.1) in any well type (public supply, domestic, monitoring). Most (57 of 77) pesticides and VOCs with human-health benchmarks were detected at concentrations well below these levels (BQmax less than 0.1) for all three well types; however, BQmax values ranged from 0.1 to 3,000 for 6 pesticides and 14 VOCs. Of these 20 contaminants, one pesticide (dieldrin) and three VOCs (1,2-dibromoethane, tetrachloroethylene, and trichloroethylene) both (1) were measured at concentrations that met or exceeded MCL or HBSL values, and (2) were detected in more than 10 percent of samples collected from raw ground water used as sources of drinking water (public-supply and (or) domestic wells) and, therefore, are particularly relevant to human health. The occurrence of multiple pesticides and VOCs in individual wells also was evaluated in a human-health context because at least 53 different contaminants were detected in each of the three well types. To assess the relative human-health importance of the occurrence of multiple contaminants in different wells, the BQ values for all contaminants in a given well were summed. The median ratio of the maximum BQ to the sum of all BQ values for each well ranged from 0.83 to 0.93 for all well types, indicating that the maximum BQ makes up the majority of the sum for most wells. Maximum and summed BQ values were statistically greater for individual public-supply wells than for individual domestic and monitoring wells. The HBSL approach is an effective tool for placing water-quality data in a human-health context. For 79 of the 182 compounds analyzed in this study, no USEPA drinking-water standards or guidelines exist, but new HBSL values were calculated for 39 of these 79 compounds. The new HBSL values increased the number of detected pesticides and VOCs with human-health benchmarks from 65 to 77 (of 97 detected compounds), thereby expanding the basis for interpreting contaminant-occu