ISSN:1051-5658    

DOI:10.1002/rem.3440070302

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

年代:1997

数据来源: WILEY

摘要:

AbstractThe former Nebraska Ordnance Plant site in east‐central Nebraska was included on the National Priorities List because of explosives and trichloroethene contamination. The preferred groundwater remedy includes hydraulic containment of the contaminated groundwater and focused extraction of the more highly contaminated groundwater as components of the remedial action. The purpose of hydraulic containment is to stop the spread of contamination, while the more aggressive focused extraction will be used to speed up the remediation and reduce total cleanup costs. This case study illustrates how straightforward groundwater models were combined with uncertainty analysis to select a precise definition of the focused extraction areas. The purpose of the analysis was to reduce ultimate remediation costs, given the significant uncertainty associated with the estimated remediation times. The selected definition provides a basis for more sophisticated groundwater modeling, the goal of which was to locate extraction wells and define their flow rates. The batch flushing model provided the governing equations, and Monte Carlo analysis was used for the uncertainty analysis. All of the analysis was performed on a personal computer using commercially available softwar

ISSN:1051-5658    

DOI:10.1002/rem.3440070303

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

年代:1997

数据来源: WILEY

摘要:

AbstractPotential health risks and cleanup costs are primary factors for measuring the effectiveness of a remediation project concerning a site contaminated with residual radioactive materials. Demanding cleanup of a contaminated site to its original condition, while eliminating any health risks after cleanup, can require prohibitive costs. However, by setting practical remediation objectives and by performing realistic but conservative risk assessments, health risks can be acceptable and cleanup costs can be reasonable. This article uses the South‐Middle and Southeast Vaults Decontamination and Demolition Project at Argonne National Laboratory to demonstrate how negligible health risks can result after cleanup with minimal cleanup costs. Substantial cost savings of approximately $2 million was realized by implementing in‐place decontamination and demolition (D&D) on the basis of acceptable risk, instead of requiring cleanup of the site to its original condition. By using the RESRAD computer program as a modeling tool, we show the maximum projected radiation dose (0.1 mrem per year) and the potential lifetime cancer risk (on the order of 106) to an individual from exposure to the residual radioactivities are negligibly small. In addition to aiding in the selection of a preferred remediation alternative, results of the RESRAD modeling were also used to guide the implementation of the selected alternative to reduce exposures from the dominant pathway and to ensure that exposures from all pathways would be as low as reasonably achieva

ISSN:1051-5658    

DOI:10.1002/rem.3440070304

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

年代:1997

数据来源: WILEY

摘要:

AbstractThis article illustrates how two different decision analysis (DA) methods can be used to assist in making environmental remediation decisions. The two DA methods are Multiattribute Utility Theory (MAUT) and the Analytic Hierarchy Process (AHP). MAUT and AHP differ greatly in their underlying philosophies. MAUT employs an interval scale and constructs utility functions that quantify the total utility to the decision maker of each technology alternative; AHP employs a ratio scale and uses pairwise comparisons to produce a final ranking of the alternatives that reflects the decision maker's comparative preferences. In this study, the same technology was ranked first by both methods; however, the remaining rankings did not agree. Also, statistical analysis indicated that some score differences may be statistically insignificant. These results are presented and discussed along with a comparison of the features, advantages, and disadvantages of these two DA approaches.

ISSN:1051-5658    

DOI:10.1002/rem.3440070305

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

年代:1997

数据来源: WILEY

摘要:

AbstractEPA's use of a 1 part per billion (ppb) level for dioxin contamination in residential soils is shown to be too high and not protective of public health. It was derived in a 1984 cancer risk assessment by another federal agency, but it is inconsistent with risk‐based levels of 2 to 4 parts per trillion (ppt) obtained by using EPA's standard risk assessment methods. EPA has called the 1 ppb level a policy‐based level, which correctly distinguishes it from a risk or health‐based cleanup standard. The 1984 assessment is shown in this article to have considerable shortcomings. For over a decade, dioxins have been left in soils at levels posing health risks and sometimes at levels that EPA is legally required to address. Moreover, noncancer effects have been ignored, but recent work has shown them to support action at low ppt levels. To protect public health, be consistent with current scientific knowledge and other EPA policies, reduce confusion in the environmental management community, and be responsive to public demands for stringent dioxin cleanups, new EPA policy guidance for dioxin soil cleanups is needed, and key elements are presented in this article. In an ad hoc fashion, EPA Region 4 has recently used a 200 ppt dioxin cleanup level for residential soil, acknowledged to correspond to a one‐in‐ten‐thousand cancer risk, at two Superfund sites, which environmental professionals should be aware of. This suggests a shift in

ISSN:1051-5658    

DOI:10.1002/rem.3440070306

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

年代:1997

数据来源: WILEY

摘要:

AbstractAdaptive sampling and analysis programs (ASAPs) provide a cost‐effective alternative to traditional sampling program designs. ASAPs are based on field analytical methods for rapid sample turnaround and field‐based decision support for guiding the progress of the sampling program. One common objective of ASAPs is to delineate contamination present in soils, either to support feasibility studies or remedial action designs. An ASAP based on portable gas chromatograph/ mass spectrograph (GC/MS) technologies developed at Tufts University combined with decision support tools created at Argonne National Laboratory was used to delineate explosives contamination in soils at Joliet Army Ammunition Plant, Joliet, Illinois. Tufts' GC/MS technologies provided contaminant‐specific identification and quantification with rapid sample turnaround and high sample throughput. Argonne's decision support tools estimated contamination extent, determined the uncertainty associated with those estimates, and indicated where sampling should continue to minimize uncertainty. In the case of Joliet, per sample analytical costs were reduced by 75 percent as compared to the cost of off‐site laboratory analyses for explosives. The use of an ASAP resulted in a much more accurate identification and delineation of contaminated areas than a traditional sampling program would have with the same number of samples collected on a regular grid. While targeting explosives contamination in soils at Joliet, the ASAP technologies used in this demonstration have much broader appl

ISSN:1051-5658    

DOI:10.1002/rem.3440070307

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

年代:1997

数据来源: WILEY

摘要:

AbstractDecisions that determine the proper risk‐based remediation approach are based on technical, regulatory, cost, legal, and political factors. A wide variety of options such as the ASTM RBCA tiered approach, the API Decision Support Software, and a host of agency‐specific methods and commercial risk assessment software are all available. The optimization of a remediation project requires the right remediation technology coupled with the appropriate analytical framework. For groundwater remediation, the application of various “risk reduction” technologies can be classified as aggressive (pump and treat), moderate intensity (air sparging), low intensity (oxygen release compound‐ORC®), and intrinsic (monitor only). The time frame of risk analysis will establish the proper risk reduction strategy. The selection process is inherently iterative, and the approach by which an optimal solution can be derived forms the basis of this article. A case study of a Texas site put these issues in

ISSN:1051-5658    

DOI:10.1002/rem.3440070308

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

年代:1997

数据来源: WILEY

摘要:

AbstractThere are numerous technologies currently being tested by EPA, universities throughout the world, and private research organizations. A few of the more promising innovative technologies as well as fully tested and proven remedies for treating contaminated groundwater are presented in this article. Although several of those technologies have been in existence for only four to five years, the results of full‐scale testing are being produced. The method for each of these promising technologies is described, results from recent field‐scale studies are summarized, and a discussion of cost is presen

ISSN:1051-5658    

DOI:10.1002/rem.3440070309

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

年代:1997

数据来源: WILEY

ISSN:1051-5658    

DOI:10.1002/rem.3440070310

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

年代:1997

数据来源: WILEY

ISSN:1051-5658    

DOI:10.1002/rem.3440070311

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

年代:1997

数据来源: WILEY