摘要:

AbstractAs the limitations of site remedial technologies become more apparent and greater experience in their field implementation and effectiveness is gained, increased emphasis is placed on development of a structured technology selection process. Ideally, this selection process should yield the most cost‐effective technology, which will accomplish cleanup goals in the shortest time frame. Although laboratory treatability studies comprise an essential component of this process, very little has been written about the methodology of designing, executing, and assessing the value of their results. This article presents practical considerations for environmental professionals who use treatability results in technology selection or others who execute such studie

ISSN:1051-5658    

DOI:10.1002/rem.3440030402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThis article provides an overview of a dynamic methodology leading to the estimation of the level of mercury concentration in soil and soil cleanup volumes associated with a large number of gate stations suspected of having mercury in their soil. The methodology uses a unique screening approach that has been developed for relating measurements of volatile mercury near the surface to mercury concentration in the upper soil subsurface (about twelve inches deep). The screening approach was used in an effort to reduce the number of sites that are subject to extensive multimedia environmental sampling and analysis. The approach helps to focus on a small number of sites that are suspected of having the highest mercury concentration in soil, perform multimedia environmental sampling at these sites, use the field data to perform risk assessment, and determine the cleanup action levels and the volume of hot spots soil to be cleaned at these sites. The information obtained for the most contaminated sites is used to determine, if required, the level of cleanup for less contaminated sites.

ISSN:1051-5658    

DOI:10.1002/rem.3440030403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractEnvironmental consulting is a relatively new and rapidly growing field. It involves traditional engineering and construction risks as well as the specter of potential—and likely uninsured or uninsurable—liability for environmental conditions and professional errors. To succeed in today's litigious society, environmental consultants and contractors need to understand the risks inherent in their work. They must conduct their operations in a manner conducive to quality assurance, risk control, and effective project management. Constant and clear communication with the client is essential to a good working relationship and repeat business. Effective project control, risk management, file documentation, and contract negotiation are critical tools for profitable growth and our professional liability defe

ISSN:1051-5658    

DOI:10.1002/rem.3440030404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractThis article explains new EPA regulations that provide for use of corrective action management units (CAMUs) and temporary units (TUs) as cost‐effective techniques for remediating hazardous wastes at facilities undergoing RCRA corrective action and at CERCLA remediation sites. The author outlines EPA criteria for approving the use of CAMUs, discusses the benefits and limitations of using them, and recommends possible ways to improve on the CAMU concep

ISSN:1051-5658    

DOI:10.1002/rem.3440030405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractBecause of increased awareness and knowledge about their behavior, dense nonaqueous phase liquids (DNAPLs) are being detected at an increasing frequency at hazardous and solid waste land disposal units. Remedial systems at sites containing DNAPLs need to be designed to address the specific problems presented by DNAPLs. Because of their physical properties, DNAPLs migrate downward and are difficult to remove using conventional recovery methods. Groundwater pumping schemes can be designed to hydraulically contain this vertical migration. The purpose of this article is to present an approach for evaluating the potential to halt the vertical migration of DNAPLs using hydraulic control.Detailed groundwater flow modeling of a group of waste basins indicates that groundwater pumping in low‐permeability sands can impose the upward hydraulic gradients required to stop downward DNAPL movement. However, a recovery well system located around the perimeter of the waste basins will not impose the required gradients over a sufficiently large area to effectively contain DNAPLs under the basins because the distribution of vertical gradients that could stop DNAPLs extends only about fifty to sixty feet from the wells. Additional modeling indicates that horizontal recovery wells located directly under the basins can contain the vertical migration of DNAPL

ISSN:1051-5658    

DOI:10.1002/rem.3440030406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractHalogenated and nonhalogenated hydrocarbon contaminants are currently found in natural waterways, groundwater, and soils as a result of spills and careless disposal practices. The development of proper treatment methodologies for the waste streams producing this environmental damage is now a subject of growing concern. A significant number of these waste stream compounds are chemically stable and are thus resistant to environmental degradation.Numerous researchers have investigated the use of ionizing radiation to decompose chlorinated hydrocarbons in diverse matrices and have proposed various free‐radical‐induced reaction mechanisms.This article is divided into two sections. First, we present data on experimentally measured, radiolytically induced decomposition of hazardous wastes and toxic substances using accelerator‐generated bremsstrahlung sources and gamma radiation from cobalt‐60. Data are presented on the radiolytically induced reduction in concentration of volatile organic compounds (VOCs) dissolved in water and in air, polychlorinated biphenyls (PCBs) dissolved in oil, high explosives dissolved in groundwater, and chemical weapon surrogates. The results of these studies suggest the potential use of ionizing radiation as a method of hazardous waste treatment.The second section of this article describes the technical aspects of a field‐scale radiolytic decomposition site cleanup demonstration using an electron accelerator. A portable, commercially available electron accelerator was set up at the Lawrence Livermore National Laboratory's (LLNL's) Site 300, a Superfund site, where vacuum extraction wells were removing trichloroethylene (TCE) vapor from a ground spill into the unsaturated soil zone. The accelerator was retrofitted into the existing vacuum extraction system such that the extracted TCE‐containing vapor passed through the accelerator beam for treatment. The concentration of TCE in the vapor was reduced by an amount dependent on the accelerator beam power. Production of reaction products in the vapor was measured as a function of ab

ISSN:1051-5658    

DOI:10.1002/rem.3440030407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

摘要:

AbstractContaminated groundwater at a chemical antioxidant and phenolic resin chemical production site was subjected to treatability studies to develop design criteria for surface water discharge. Raw groundwater required pretreatment for total suspended solids (TSS) and color removal prior to treatment by ultraviolet light/hydrogen peroxide (UV/H2O2). Because of high capital and operating costs for UV/H2O2, biological treatment was evaluated as an alternate. Respirometric analyses showed that completely mixed activated sludge could be applied as a treatment technology to the groundwater. Biotreatment resulted in an approximately 70 percent reduction in soluble chemical oxygen demand (SCOD). Residual SCOD was recalcitrant to further biodegradation. The treated effluent was tested for aquatic toxicity using fathead minnows (Pimephales promelas) andCeriodaphnia dubiaand was found to be toxic. Toxicity reduction of biotreatment effluent was evaluated in bench‐scale experiments using activated carbon adsorption, filtration, and UV/H2O2. Subsequent toxicity testing showed that filtration alone could reduce the bioeffluent toxicity and that residual SCOD was not the primary source of toxicit

ISSN:1051-5658    

DOI:10.1002/rem.3440030408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

ISSN:1051-5658    

DOI:10.1002/rem.3440030409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

ISSN:1051-5658    

DOI:10.1002/rem.3440030411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY

ISSN:1051-5658    

DOI:10.1002/rem.3440030412

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1993

数据来源: WILEY