Practical Methods for Meeting Remediation Goals at Hazardous Waste Sites

Risk-based cleanup goals or preliminary remediation goals (PRGs) are established at hazardous waste sites when contaminant concentrations in air, soil, surface water, or groundwater exceed specified acceptable risk levels. When derived in accordance with the Environmental Protection Agency's risk assessment guidance, the PRG is intended to represent the average contaminant concentration within an exposure unit area that is left on the site following remediation. The PRG, however, frequently has been used inconsistently at Superfund sites with a number of remediation decisions using the PRG as a not-to-exceed concentration (NTEC). Such misapplications could result in overly conservative and unnecessarily costly remedial actions. The PRG should be applied in remedial actions in the same manner in which it was generated. Statistical methods, such as Bower's Confidence Response Goal, and mathematical methods such as "iterative removal of hot spots," are available to assist in the development of NTECs that ensure the average postremediation contaminant concentration is at or below the PRG. These NTECs can provide the risk manager with a more practical cleanup goal. In addition, an acute PRG can be developed to ensure that contaminant concentrations left on-site following remediation are not so high as to pose an acute or short-term health risk if excessive exposure to small areas of the site should occur. A case study demonstrates cost savings of five to ten times associated with the more scientifically sound use of the PRG as a postremediation site average, and development of a separate NTEC and acute PRG based on the methods referenced in this article.     

Remedial Policies in Radiologically-Contaminated Forests: Environmental Consequences and Risk Assessment

As a result of the Chernobyl nuclear power plant accident in 1986, large forested areas in Europe were contaminated by radionuclides. Extensive societal pressure has been exerted to decrease the radiation dose to the population and to the environment. Thus, in making abatement and remediation policy decisions not only economic costs, but also human and environmental risk assessment are desired. Forest remediation by organic layer removal, one of the most promising cleanup policies, is considered in this paper. Ecological risk assessment requires evaluation of the radionuclide distribution in forests. The FORESTPATH model^(1,2) is used for predicting the radionuclide fate in forest compartments after deposition as well as for evaluating the application of the remedial policy. Time of intervention and radionuclide deposition profile was predicted as being crucial for the remediation efficiency. Risk assessment conducted for a critical group of forest users in Belarus shows that consumption of forest products (berries and mushrooms) leads to about 0.004% risk of a fatal cancer. Cost-benefit analysis for forest cleanup suggests that complete removal of organic layer is too expensive for application in Belarus.     

反垄断法私人实施制度的价值

反垄断法实施制度的运行目标和功能主要是对理性行为主体的威慑、为垄断违法行为导致的危害后果提供救济,以及解释、明确反垄断法针对对象的范围和实施标准。私人实施在实现这三个目标和功能方面有着十分特殊的价值。我国反垄断法的私人实施制度相关规则有待进一步的细化和完善,在此过程中应当注重明确反垄断法实施的目标和功能,规则制定要具有科学性、前瞻性,同时注意把握私人实施与公共实施之间的互动关系。     

Paying for permanence: Public preferences for contaminated site cleanup

We use conjoint choice questions to investigate the preferences of people in four cities in Italy for income and future/permanent mortality risk reductions delivered by contaminated site remediation policies. The VSL is €5.6 million for an immediate risk reduction. If the risk reduction takes place 20 years from now, the implied VSL is €1.26 million. Respondents’ implicit discount rate is 7%. The VSL depends on respondent characteristics, familiarity with contaminated sites, concern about the health effects of exposure to toxicants, having a family member with cancer, perceived usefulness of public programs and beliefs about the goals of government remediation programs.

Deliberation: Integrating Analytical Results into Environmental Decisions Involving Multiple Stakeholders

The National Research Council has recommended the use of an analytic/deliberative decision making process in environmental restoration decisions that involve multiple stakeholders. This work investigates the use of the results of risk assessment and multiattribute utility analysis (the "analysis") in guiding the deliberation. These results include the ranking of proposed remedial action alternatives according to each stakeholder's preferences, as well as the identification of the major reasons for these rankings. The stakeholder preferences are over a number of performance measures that include the traditional risk assessment metrics, e.g., individual worker risk, as well as programmatic, cultural, and cost-related impacts. Based on these results, a number of proposals are prepared for consideration by the stakeholders during the deliberation. These proposals are the starting point for the formulation of actual recommendations by the group. In our case study, these recommendations included new remedial action alternatives that were created by the stakeholders after an extensive discussion of the detailed analytical results.     

Selecting a Portfolio of Technologies: An Application of Decision Analysis

The Department of Energy is faced with the critical and complex decision of selecting technologies for waste site remediation. This research focuses on developing a decision support tool which assists the decision maker to find an optimal portfolio. A portfolio consists of selecting the appropriate processes for a remediation site and, subsequently, selecting a technology for each process so that the decision maker's objectives are achieved. The measures supporting the objectives are risk, life-cycle cost, and time required for remediation. The model uses exponential attribute utility functions with an additive objective function. The model provides the decision maker with estimates of the cost and time distributions, and their associated utility. Cumulative frequency distributions illustrate the dominance of technology choices and the variance in the results. The model permits sensitivity analysis in the form of rainbow and tornado diagrams to display the effects of changes in the values of the input variables. Overall, the model provides a generic technology selection tool that can be used to make better informed decisions and may be easily manipulated to reflect changes in the remediation process.     

不同经济发展水平地区农村居民点整治意愿研究———基于山东省和福建省两地农户的调查

以山东省和福建省为例,通过农户调查对两地农村居民点整治意愿进行实证研究,旨在比较分析不同经济发展水平地区农村居民点整治意愿,探索农村居民点整治的实施机制,为保障农村居民点整治的顺利开展提供借鉴.结果显示,两个样本区农户居民点整治意愿都比较高,普遍对居住环境改善的期望较高,并且补偿方式上倾向于选择一次性货币补偿;不同经济发展水平地区农户在土地处理方式与安置方式上有不同的诉求:在土地处理方面,经济发展水平较高地区,农户较为愿意将其土地全部征收,多数愿意转为镇民,反之,农户只较为愿意进行居民点整治,转为镇民的意愿较低;在安置方式方面,虽然都较为愿意选择就地集中改造建村或新建中心村,但是,经济发展水平较高地区,存在部分农户倾向于选择获取补偿自行进城购房的安置方式,反之则不存在.针对分析结果,提出了相应的对策建议.