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Trichloroethylene (TCE), a frequently used chlorinated solvent has been completely degraded in aqueous solution over the as-synthesised Cu-TiO2 irradiated with UV light. The effect of pH and the role played by specific generated reactive oxygen species in the mineralisation process were evaluated. Cu-TiO2 was synthesised and characterised according to our previous study. The photodegradation results, which followed the pseudo-first-order kinetic model, revealed that pH had a negligible effect on the degradation as the complete dechlorination occurred in all adjusted pH solutions. In addition, probe compound tests using nitrobenzene and tetrachloromethane suggested that the hydroxyl radical (•OH) is mainly generated when coupling UV with Cu-TiO2, and the superoxide radical anion (O2•−) is highly generated when UV is applied alone. Free radical quenching studies demonstrated that O2•− is the major radical responsible for the degradation of TCE compared to •OH. The results obtained in the present study can serve as a support for further studies on the removal of TCE using UV coupling catalyst.

This study evaluated the long-term performance of enhanced anaerobic bioremediation (EAB) at chlorinated solvent sites to determine if sustained treatment processes were helping to prevent concentration rebound. A database of groundwater concentration versus time records was compiled for 34 sites, with at least 3 years of posttreatment monitoring data (­median = 4.7 years, range = 3.0 to 11.7 years). Long-term performance was evaluated based on order-of-magnitude (OoM) changes in parent compound concentrations during various monitoring periods. Results indicate that, relative to the pretreatment concentration, a median concentration reduction for all 34 sites of 1.0 OoM (90% reduction) was achieved by the end of the posttreatment monitoring period. No rebound was observed at 65% of the sites between the first year of posttreatment monitoring and the final year. During this posttreatment period, Mann-Kendall trend analysis indicated that the concentration was stable or decreasing at 89% of the sites where a trend could be established (n = 27; 33% decreasing, 56% stable, 11% increasing). Statistical analysis indicates there is no evidence that the distribution of median concentration reductions after the first year of posttreatment monitoring was different than the distribution of median reductions 2 to 11 years later at the end of the monitoring period (p = 0.67). Similarly, statistical analysis indicates that there is no evidence that the distribution of median reductions for a larger set of sites (n = 84) with less than 3 years of posttreatment monitoring data (1.1 OoM; 92% reduction) was different than the distribution of median OoM reductions for the 34-site dataset with longer monitoring periods (p = 0.80). This suggests that, at a typical site, a 3-year monitoring period should be sufficient for evaluating performance. The results of this study indicate that, in the long term, after the end of active treatment, sustained treatment processes contribute to relatively modest concentration reductions but do mitigate rebound at the majority of EAB sites.

Contamination by chlorinated solvents is typically associated with point sources, which are able to release high concentrations and to generate well defined plumes. Nevertheless, in urban settings (especially in functional urban areas—FUAs), multiple-point sources are frequently present, consisting of a series of unidentifiable small sources clustered within large areas, generating a diffuse, anthropogenic contamination. This situation results in the coexistence of single plumes with higher contaminant concentrations, and larger areas where the concentration is lower but still higher than the maximum admissible concentration limits. This paper proposes a methodology devised to cope with the diffuse contamination by chlorinated solvents within shallow aquifers due to multiple-point sources in FUAs. The approach is based on a Bayesian model that helps to spatially evaluate the likelihood of having active multiple-point sources, and to relate their impact on the shallow aquifer to the hydrogeological features of the area. Moreover, the approach allows testing of the efficiency of the monitoring network to properly characterize the contamination in the aquifer. The consistency of the results of the analysis was also checked for the Milan FUA (Italy) by a comparison to a previous study, performed through an inverse numerical modelling approach within a Monte Carlo statistical framework to identify the areas with the highest likelihood to host potential multiple-point sources.

Many uses of trichloroethylene (TCE) pose unreasonable health risks to workers and consumers, the US Environmental Protection Agency says in its latest evaluation of the chlorinated solvent. The dr...

Nowadays, the main challenge in the actual road infrastructure context is to guarantee an efficient, safe and durable road network for daily users. Without a regular maintenance, road pavement materials are ageing and lead to a local deterioration. To better predict the durability, it is also essential to assess road pavement materials properties after ageing. In literature, asphalt mixture ageing is often assessed by the measurement of consistency, oxidation and rheological properties on the binder, which is previously extracted with a chlorinated solvent. However, this method is solvent and time consuming; it also lies on the dissolution and possible modification of the bitumen structure. Therefore, the paper aims at developing an in-situ method to directly assess the ageing state in compacted road pavement asphalt mixtures. Based on a statistical chemomap Imaging ATR methodology, variations in the microscopic carbonyl absorbance are quantified in the analyzed bituminous mastic of recycled asphalt mixtures displaying different oxidation states. Results allow successfully validating the direct measurement of microscopic oxidation properties on asphalt mixture specimens. Through the calculation of a microscopic oxidation average, the degree of remobilization can be indirectly assessed in bituminous mixtures incorporating reclaimed asphalt. More largely, the statistical chemomap method opens new perspectives to link the measurement of local oxidative ageing properties with mechanical behavior of compacted asphalt mixtures specimens, for a better prediction of road materials performances and durability.

Electrochemical reduction of 9,10-phenanthrenequinone, benzil and acenaphthenequinone in 1,1,1-trichloroethane (TCE)/TBAP under constant potential conditions provides an interesting entry to new coupling products through an electron-transfer reaction in solution to the chlorinated solvent. This electroinduced reaction points out the differences in the reaction pathway followed by these 1,2-dicarbonyl compounds depending on their geometry. The intermediates nature and their behavior, both in solution and at the electrode surface, are discussed.

The combination of electrokinetic and zero-valent iron (ZVI) treatments were used to treat soils contaminated with chlorinated solvents, including dense nonaqueous phase liquid (DNAPL), at an active industrial site in Ohio. The remediation systems were installed in tight clay soils under truck lots and entrances to loading docks without interruption to facility production. The electrokinetic system, called LasagnaTM, uses a direct current electrical field to mobilize contaminant via electroosmosis and soil heating. The contaminants are intercepted and reduced in situ using treatment zones containing ZVI. In moderately contaminated soils around the LasagnaTM-treated source areas, a grid of ZVI filled boreholes were emplaced to passively treat residual contamination in decades instead of centuries. The remediation systems were installed below grade and did not interfere with truck traffic during the installation and three years of operation. The LasagnaTM systems removed 80 percent of the trichloroethylene (TCE) mass while the passive ZVI borings system has reduced the TCE by 40 percent. The remediation goals have been met and the site is now in monitoring-only mode as natural attenuation takes over. © 2014 Wiley Periodicals, Inc.

The industrial solvent, trichloroethene (TCE), is among the most ubiquitous chlorinated compounds found in subsurface contamination. Operation of an avionics repair shop at a military base has resulted in past release of solvent chemicals including TCE and other chlorinated aliphatic hydrocarbons. The objectives of this study were to investigate the occurrence of natural remediation process and the feasibility of using natural remediation as the remedial option at this site. The following tasks have been performed: (1) site characterization to delineate the lateral and vertical extent of contaminants in the subsurface; (2) field investigation of natural remediation; and (3) efficiency of TCE removal through natural remediation in the field. Results indicate that TCE biodegradation occurred at this site, and natural remediation is a possible remedial alternative for TCE plume containment. Evidences for the TCE natural remediation included: (1) decreased TCE and other chlorinated compounds concentrations along the transport path; (2) production of the TCE degradation byproducts (including ethane); (3) decreased total organic carbon along the transport path, (4) deceased pH in the spill source area; (5) production of chloride ion and carbon dioxide. Experiences obtained from this study would be helpful in developing a site remedial protocol for other DNAPL sites.

Cobalamin and other corrinoids are essential cofactors for many organisms. The majority of microbes with corrinoid-dependent enzymes do not produce corrinoids de novo, and instead must acquire corrinoids produced by other organisms in their environment. However, the profile of corrinoids produced in corrinoid-dependent microbial communities, as well as the exchange and modification of corrinoids among community members have not been well studied. In this study, we applied a newly developed liquid chromatography tandem mass spectrometry-based corrinoid detection method to examine relationships among corrinoids, their lower ligand bases and specific microbial groups in microbial communities containing Dehalococcoides mccartyi that has an obligate requirement for benzimidazole-containing corrinoids for trichloroethene respiration. We found that p-cresolylcobamide ([p-Cre]Cba) and cobalamin were the most abundant corrinoids in the communities. It suggests that members of the family Veillonellaceae are associated with the production of [p-Cre]Cba. The decrease of supernatant-associated [p-Cre]Cba and the increase of biomass-associated cobalamin were correlated with the growth of D. mccartyi by dechlorination. This supports the hypothesis that D. mccartyi is capable of fulfilling its corrinoid requirements in a community through corrinoid remodelling, in this case, by importing extracellular [p-Cre]Cba and 5,6-dimethylbenzimidazole (DMB) (the lower ligand of cobalamin), to produce cobalamin as a cofactor for dechlorination. This study also highlights the role of DMB, the lower ligand produced in all of the studied communities, in corrinoid remodelling. These findings provide novel insights on roles played by different phylogenetic groups in corrinoid production and corrinoid exchange within microbial communities. This study may also have implications for optimizing chlorinated solvent bioremediation.

The US Department of Defense should overhaul its process for establishing a workplace exposure limit for the chlorinated solvent trichloroethylene (TCE), a Nov. 15 report by a National Academies of Sciences, Engineering, and Medicine committee says. The report questions why the DOD did not follow best practices in its hazard assessment and review of published studies on the health effects of TCE. Deviating from best practices “puts the agency in a position of having to develop, document, and defend a different approach, which is particularly difficult when applied to a chemical with a large and controversial database, such as TCE,” the report states. TCE is a human carcinogen and has adverse effects on the liver, kidneys, brain, and immune system, as well as on reproduction. The DOD is concerned about people inhaling TCE while working in facilities near contaminated DOD sites. The US military once widely used TCE as a

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

There are few published reports of allocation methodologies for contamination at complex sites not associated with the traditional Superfund landfill scenario (i.e., based on waste in records). Allocation can be especially difficult when the contamination is derived from neighboring facilities. Such was the situation in a lawsuit brought by Solvent Chemical (Solvent) in the United States District Court for the Western District of New York (New York v. Solvent Chem. Co., Inc., 685 F. Supp. 2d 357 (W.D.N.Y)). Solvent had filed a cost-recovery and contribution claim against Olin and DuPont, neighboring industrial facilities, to recover costs associated with groundwater and soil remediation. Solvent alleged that the contamination found in groundwater recovery wells on the Solvent site was predominately due to releases from the former adjacent Dupont chlorinated solvent production facility and from Olin's neighboring former chlorinated benzene production facility. However, complicating matters for Solvent was ...

Groundwater systems are increasingly used for seasonal aquifer thermal energy storage (SATES) for periodic heating and cooling of buildings. Its use is hampered in contaminated aquifers because of the potential environmental risks associated with the spreading of contaminated groundwater, but positive side effects, such as enhanced contaminant remediation, might also occur. A first reactive transport study is presented to assess the effect of SATES on the fate of chlorinated solvents by means of scenario modeling, with emphasis on the effects of transient SATES pumping and applicable kinetic degradation regime. Temperature effects on physical, chemical, and biological reactions were excluded as calculations and initial simulations showed that the small temperature range commonly involved (ΔT < 15 C) only caused minor effects. The results show that a significant decrease of the contaminant mass and (eventually) plume volume occurs when degradation is described as sediment-limited with a constant rate in space and time, provided that dense non-aqueous phase liquid (DNAPL) is absent. However, in the presence of DNAPL dissolution, particularly when the dissolved contaminant reaches SATES wells, a considerably larger contaminant plume is created, depending on the balance between DNAPL dissolution and mass removal by degradation. Under conditions where degradation is contaminant-limited and degradation rates depend on contaminant concentrations in the aquifer, a SATES system does not result in enhanced remediation of a contaminant plume. Although field data are lacking and existing regulatory constraints do not yet permit the application of SATES in contaminated aquifers, reactive transport modeling provides a means of assessing the risks of SATES application in contaminated aquifers. The results from this study are considered to be a first step in identifying the subsurface conditions under which SATES can be applied in a safe or even beneficial manner. © 2013 Elsevier B.V.

BACKGROUND: Exposure to dichloromethane (DCM or methylene chloride - CH2 Cl2 ) in paint strippers continues to be an avoidable source of morbidity and mortality. DCM has been under regulatory scrutiny by occupational and consumer product agencies since the identification of its carcinogenicity in the mid-1980s. METHODS: We investigated two independent workplace incidents that resulted in three cases of DCM intoxication from paint stripper use. RESULTS: Each incident investigated resulted in a fatality. A third worker suffered obtundation requiring hospitalization and intubation. CONCLUSIONS: The continued occurrence of fatalities and other serious injuries due to DCM-containing paint strippers in the United States calls for a re-evaluation of existing regulatory strategies. Am. J. Ind. Med. © 2013 Wiley Periodicals, Inc. Language: en

Åtskilliga områden i Sverige bedöms vara förorenade med klorerade lösningsmedel som är toxiska för människa och miljö. I begreppet klorerade lösningsmedel ingår bland annat klorerade etener, till exempel perkloreten och trikloreten. Dessa är starkt förknippade med förorening från kemtvättar samt mekaniska industrier. Föroreningarna går att bryta ned med mikrobiella metoder men för att resultatet ska bli lyckat krävs goda mikrobiella och kemiska kunskaper. Vid många svenska saneringar av akvifärer som förorenats av kemtvättar har man använt sig av biostimulering, som är en typ av förstärkt mikrobiell självrening. Biostimulering innebär att man genom tillsats in situ av kolkälla stimulerar den naturliga nedbrytningen. En kompletterande teknik är bioaugmentation varvid man tillsätter speciellt utvalda mikroorganismer. Bioaugmentation är en etablerad teknik i till exempel USA, men har hittills bara använts vid enstaka förorenade objekt i Sverige. Denna publikation förklarar varför det ibland krävs en kombination av biostimulering och bioaugmentation för att saneringen ska bli lyckad. I publikationen beskrivs hur man undersöker om det finns behov av att kombinera metoderna samt hur de båda åtgärdsmetoderna kan utföras i full skala. Publikationen baseras på omfattande studier av främst utländsk litteratur, listade i en separat Bilaga. Textinnehållet i publikationen exemplifieras delvis med diagram vars underliggande data är hämtade från erfarenheter erhållna i ett projekt utfört i pilotskala, i en kloretenförorenad akvifär vid Alingsås tvätteri.

Annually, thousands of oil spills occur across the globe. As a result, petroleum substances and petrochemical compounds are widespread contaminants causing concern due to their toxicity and recalcitrance. Many remediation strategies have been developed using both physicochemical and biological approaches. Biological strategies are most benign, aiming to enhance microbial metabolic activities by supplying limiting inorganic nutrients, electron acceptors or donors, thus stimulating oxidation or reduction of contaminants. A key issue is controlling the supply of electron donors acceptors. Bioelectrochemical systems (BES) have emerged, in which an electrical current serves as either electron donor or acceptor for oil spill bioremediation. BES are highly controllable and can possibly also serve as biosensors for real time monitoring of the degradation process. Despite being promising, multiple aspects need to be considered to make BES suitable for field applications including system design, electrode materials, operational parameters, mode of action and radius of influence. The microbiological processes, involved in bioelectrochemical contaminant degradation, are currently not fully understood, particularly in relation to electron transfer mechanisms. Especially in sulfate rich environments, the sulfur cycle appears pivotal during hydrocarbon oxidation. This review provides a comprehensive analysis of the research on bioelectrochemical remediation of oil spills and of the key parameters involved in the process. (C) 2017 Elsevier Ltd. All rights reserved.

A procedure for the design of an aerobic cometabolic process for the on-site degradation of chlorinated solvents in a packed bed reactor was developed using groundwater from an aquifer contaminated by trichloroethylene (TCE) and 1,1,2,2-tetrachloroethane (TeCA). The work led to the selection of butane among five tested growth substrates, and to the development and characterization from the site's indigenous biomass of a suspended-cell consortium capable to degrade TCE (first order constant: 96 L gprotein(-1) day(-1) at 30 °C and 4.3 L gprotein(-1) day(-1) at 15 °C) with a 90 % mineralization of the organic chlorine. The consortium immobilization had strong effects on the butane and TCE degradation rates. The microbial community structure was slightly changed by a temperature shift from 30 to 15 °C, but remarkably affected by biomass adhesion. Given the higher TCE normalized degradation rate (0.59 day(-1) at 15 °C) and attached biomass concentration (0.13 gprotein Lbioreactor(-1) at 15 °C) attained, the porous ceramic carrier Biomax was selected as the best option for the packed bed reactor process. The low TeCA degradation rate exhibited by the developed consortium suggested the inclusion of a chemical pre-treatment based on the TeCA to TCE conversion via β-elimination, a very fast reaction at alkaline pH. To the best of the authors' knowledge, this represents the first attempt to develop a procedure for the development of a packed bed reactor process for the aerobic cometabolism of chlorinated solvents.

Introduction to Recalcitrant Compounds J.W. Talley Toxicological Exposure of Bound Recalcitrant Compounds H. Fredrickson, J.S. Furey, and J.W. Talley Roadblocks to the Implementation of Biotreatment Strategies J.W. Talley The Federal Integrated Biotreatment Research Consortium (Flask to Field) J.W. Talley Chlorinated Solvent Contaminated Soils and Groundwater: Field Application of the Solvent Extraction Residual Biotreatment Technology G. Sewell, S.C. Mravik, A.L. Wood, M. Annable, R. Sillan, and K. Warner Enhancing PCB Bioremediation J.M. Tiedje, T.V. Tsoi, K.D. Pennell, L.D. Hansen, A. Wani, and Desiree P. Howell Polycyclic Aromatic Hydrocarbons (PAHs): Improved Land Treatment with Bioaugmentation H. Prichard, J. Jones-Meehan, C. Nestler, Dr. Lance D. Hansen, William Straube, Dr. W. Jones, Dr. J. Hind, and J.W. Talley Future Needs for Research and Development J.W. Talley. Index

NbX 5 (X = F, 1a ; X = Cl, 1b ) reacted with γ-butyrolactone (but), e-caprolactam (cap), δ-valerolactam (val) in 1:1 M ratio in chlorinated solvent, affording either the neutral coordination adducts NbCl 5 L (L = but, 2a ; L = val, 2b ) or the ionic ones [NbX 4 L 2 ][NbX 6 ] (X = F, L = but, 3a ; X = F, L = val, 3b ; X = F, L = cap, 3c ; X = Cl, L = cap, 3d ). The reaction of 1a with equimolar amount of guanine (gua) in CH 3 CN resulted in the formation of the complex [NbF 4 (gua) 2 ][NbF 6 ], 3e . The addition of two equivalents of organic substrate to 1 gave selectively the compounds NbCl 5 L 2 (L = but, 4a ; L = val, 4b ) or [NbF 4 L 4 ][NbF 6 ] (L = but, 5a ; L = val, 5b ; L = cap, 5c ). The 1:2 M reaction of 1b with e-caprolactam proceeded with C–N bond activation and afforded the derivative , 6 , in high yield.

Background Previous epidemiologic findings suggest an association between exposure to trichloroethylene (TCE), a chlorinated solvent primarily used for vapor degreasing of metal parts, and non-Hodgkin lymphoma (NHL). Objectives We investigated the association between occupational TCE exposure and NHL within a population-based case–control study using detailed exposure assessment methods. Methods Cases (n = 1,189; 76% participation rate) and controls (n = 982; 52% participation rate) provided information on their occupational histories and, for selected occupations, on possible workplace exposure to TCE using job-specific interview modules. An industrial hygienist assessed potential TCE exposure based on this information and a review of the TCE industrial hygiene literature. We computed odds ratios (ORs) and 95% confidence intervals (CIs) relating NHL and different metrics of estimated TCE exposure, categorized using tertiles among exposed controls, with unexposed subjects as the reference group. Results We observed associations with NHL for the highest tertiles of estimated average weekly exposure (23 exposed cases; OR = 2.5; 95% CI, 1.1–6.1) and cumulative exposure (24 exposed cases; OR = 2.3; 95% CI, 1.0–5.0) to TCE. Tests for trend with these metrics surpassed or approached statistical significance (p-value for trend = 0.02 and 0.08, respectively); however, we did not observe dose–response relationships across the exposure levels. Overall, neither duration nor intensity of exposure was associated with NHL, although we observed an association with the lowest tertile of exposure duration (OR = 2.1; 95% CI, 1.0–4.7). Conclusions Our findings offer additional support for an association between high levels of exposure to TCE and increased risk of NHL. However, we cannot rule out the possibility of confounding from other chlorinated solvents used for vapor degreasing and note that our exposure assessment methods have not been validated.

A combination of batch and column experiments evaluated the mass transfer of two candidate partitioning electron donors (PEDs), n-hexanol (nHex) and n-butyl acetate (nBA), for enhanced bioremediation of trichloroethene (TCE)-dense nonaqueous phase liquid (DNAPL). Completely mixed batch reactor experiments yielded equilibrium TCE-DNAPL and water partition coefficients (KNW) for nHex and nBA of 21.7 ± 0.27 and 330.43 ± 6.7, respectively, over a range of initial PED concentrations up to the aqueous solubility limit of ca. 5000 mg/L. First-order liquid-liquid mass transfer rates determined in batch reactors with nBA or nHex concentrations near the aqueous solubility were 0.22 min(-1) and 0.11 min(-1), respectively. Liquid-liquid mass transfer under dynamic flow conditions was assessed in one-dimensional (1-D) abiotic columns packed with Federal Fine Ottawa sand containing a uniform distribution of residual TCE-DNAPL. Following pulse injection of PED solutions at pore-water velocities (vp) ranging from 1.2 to 6.0 m/day, effluent concentration measurements demonstrated that both nHex and nBA partitioned strongly into residual TCE-DNAPL with maximum effluent levels not exceeding 35% and 7%, respectively, of the applied concentrations of 4000 to 5000 mg/L. PEDs persisted at effluent concentrations above 5 mg/L for up to 16 and 80 pore volumes for nHex and nBA, respectively. Mathematical simulations yielded KNW values ranging from 44.7 to 48.2 and 247 to 291 and liquid-liquid mass transfer rates of 0.01 to 0.03 min(-1) and 0.001 to 0.006 min(-1) for nHex and nBA, respectively. The observed TCE-DNAPL and water mass transfer behavior suggests that a single PED injection can persist in a treated source zone for prolonged time periods, thereby reducing the need for, or frequency of, repeated electron donor injections to support bacteria that derive reducing equivalents for TCE reductive dechlorination from PED fermentation.

Remediation of chlorinated solvent DNAPL sites often meets with mixed results. This can be attributed to the diametrically opposed nature of the impacts, where the disparate dissolved-phase plume is more manageable than the localized, high-concentration source area. A wide range of technologies are available for downgradient plume management, but the relative mass of contaminants in a DNAPL source area generally requires treatment for such technologies to be effective over the long term. In many cases, the characteristics of DNAPL source zones (e.g., depth, soil heterogeneity, structural limitations) limit the available options. The following describes the successful full-scale implementation of in situ chemical reduction (ISCR) enhanced bioremediation of a TCE DNAPL source zone. In this demonstration, concentrations of TCE were rapidly reduced to below the maximum contaminant level (MCL) in less than six months following implementation. The results described herein suggest that ISCR-enhanced bioremediation is a viable remedial alternative for chlorinated solvent source zones. © 2010 Wiley Periodicals, Inc.

Perchlorate has been detectable at milligram/liter concentrations in groundwater for decades, and investigations were originally primarily limited to sites where rocket-fuel development or testing had occurred. Other compounds of concern with low-concentration toxicity have been detected at many sites and have dominated the focus of the remedial industry since the 1970s. Once a revised analytical method was developed in 1997 to detect perchlorate concentrations down to 4 µg/L, its widespread presence was recognized at many sites and led perchlorate to claim center stage attention on a national level by the early 2000s. Although perchlorate's early association with military use persists (headlines often equate perchlorate with “rocket fuel,” regardless of the actual source), perchlorate detection at non-military sites has led to the recognition that other potential sources also require consideration. The ability to definitively distinguish potential sources from one another remains a challenge even today. Initial concerns over perchlorate recalcitrance, however, have since been allayed by the repeated demonstrations of successful remediation using a variety of familiar technologies. In this sense, perchlorate remediation strategies have been an outgrowth from chlorinated solvent–focused remediation technologies that had evolved since the 1970s. The fact that in situ technologies were being deployed aggressively—an approach that took many years for the solvent remediation industry to implement with regulatory approval—even as the extent of perchlorate was still be determined at many sites, is evidence that lessons learned from decades of chlorinated solvent remediation have and will continue to benefit perchlorate remediation speed and efficiency. As the debate over risk to human health from perchlorate exposure via food and water continues, it is apparent that in situ bioremediation of soil and groundwater has been demonstrated to be a powerful tool that remedial engineers and scientists would be wise to seriously consider at any site. In Situ Bioremediation of …

GW597599 1 is a novel NK-1 antagonist currently under investigation for the treatment of CNS disorders and emesis. The initial chemical development synthetic route, derived from the one used by medicinal chemistry, involved several hazardous reagents, gave low yields, and produced high levels of wastes. Through a targeted process of research and development, application of novel techniques, and extensive route scouting, a synthetic route for GW597599 has been developed. This paper reports the optimisation work of the second stage in the chemical synthesis of GW597599: the development of a pilot-plant-suitable process for the manufacturing of an optically pure arylpiperazine derivative. In particular, the new process eliminates the need to purchase and store dangerous and expensive borane by generating it in situ and also the need for a chlorinated solvent, thereby improving the safety of the process and substantially reducing the overall waste. The final yield and throughput will be significantly enhanced.

For risk-based decision making, local and global impacts should be considered simultaneously. In metal degreasing processes, various cleansing agents are used and a significant amount of such cleansing agents is released into the environment. An appropriate measure of reducing chemical risk associated with industrial cleaning processes should be implemented on the basis of evaluation results representing the local and global impacts. In this study, we assessed metal degreasing processes using a chlorinated solvent with an open-top washing machine and four alternative scenarios, namely, improving the settings of the machine (two cases), changing the local ventilation system, and installing a recovery system using activated carbon. The applied methods are plant-specific risk and life cycle assessments. Specifically in the risk assessment, detailed process data available for decision makers are utilized to evaluate occupational and neighborhood risks. The results of this case study indicate a tradeoff relationship between the local and global impacts in metal degreasing. Through the discussions on the practicability of the integration of the local and global impacts into actual decision making, we conclude that the way to use, select, or integrate risk and life cycle assessments should be analyzed systematically as the situation demands at decision making.