Yardsticks to Integrate Risk Assessment,Risk Management,and Groundwater Remediation

Remediation of contaminated sites has focused largely on restoration of groundwater aquifers. Often the stated remedial goal is to achieve conditions allowing unrestricted use and unrestricted exposure. Such total groundwater cleanup has occurred at some sites, but is the exception rather than the rule. At the same time, significant effort occurs to perform risk assessments for potential exposure to contaminants in groundwater at sites, both before and after remediation. The logical synergy between risk assessment and remediation is for risk management to seek opportunities for optimal use of groundwater based upon realistic expectations of cleanup technologies and the relevant acceptable residual (postremediation) levels of contaminants. This article explores an approach to improve this synergistic relationship between risk assessment, risk management, and remediation for groundwater cleanups. ©2015 Wiley Periodicals, Inc.     

Economic Project Risk Assessment in Remediation Projects Prior to Construction: Methodology Development and Case Study Application

Probabilistic economic analysis, including uncertainty of probabilities and consequences of project risks, is not widely used in remediation projects. This article presents a project risk assessment (PRA) method to identify, quantify, and analyze risks in remediation projects. The suggested method is probabilistic and includes uncertainty analysis of input variables based on expert judgment. It was originally developed as a part of a sustainability assessment tool, but is viable as a stand‐alone tool for remediation projects. The method is applied to a case study: a former paint factory that is being redeveloped into a residential area. The PRA method is used for analyzing and comparing the project risks associated with four remediation options, all including excavation but with different degrees of onsite treatment. The result of the case study application shows which alternative has the lowest mean risk cost, the highest probability to have the lowest risk cost, and how the risk costs are distributed, but also, importantly, helps the user to prioritize between risk‐reduction measures. ©2015 Wiley Periodicals     

Green Remediation or Sustainable Remediation: Moving From Dialogue to Common Practice

Different points of view have emerged concerning how to best consider and address the largely unexamined ancillary environmental impacts, and more particularly the social and economic impacts, of remediation activities. These views are generally categorized as “green remediation” and “sustainable remediation.” This article dissects the commonalities and differences between “green” and “sustainable” remediation approaches. Several key obstacles to the broader implementation of sustainable remediation practices are identified. Similarities identified among the two concepts offer a common ground and areas of collaboration. The objective of this article is to support maturation of the remediation industry by addressing the opposition to and supporting the implementation of sustainable remediation practices, including offering recommendations for a path forward. ©2015 Wiley Periodicals, Inc.     

环境风险评价中氯气泄漏扩散的计算

根据HJ/T169-2004((建设项目环境风险评价技术导则>(简称<导则>),对某化工厂使用的液氯钢瓶的事故源进行分析.采用<导则>推荐的Cox和Carpenter稠密气体扩散模型,在氯气泄漏的初期,将其作为重气泄漏扩散进行计算,得到重气云团温度、半径、卷入空气质量和质量浓度随扩散时间的变化关系.计算结果与非重气扩散高斯模式的计算结果有较大差异.因此,对涉及氯气的项目进行环境风险评价时,应重视氯气作为重气泄漏扩散的环节.     

Screening Technology Trains for DNAPL Remediation

The Department of Energy (DOE) is conducting a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) mandated Remedial Investigation/Feasibility Study for a site contaminated with Dense Non-Aqueous Phase Liquid (DNAPL) pollutants. Three key efforts were a hydrogeological modeling approach, the generation of feasible sequences of technologies, and the screening of alternative technologies. This research uses a decision analysis process to provide a quantitative assessment of the candidate technologies. Decision analysis modeling was used to gain insight into each sequence of technologies. Sensitivity analysis was also conducted to assess the impact of key assumptions. The results provided the DOE with an objective and traceable rationale for screening and reducing all of the potential technology combinations to 58 technology combinations and a method for identifying the top scoring combinations. The approach has wide applicability to similar CERCLA remediation efforts.     

Cost Evaluation for Selected Remediation Technologies

Relatively little data are available to document the historical cost for using common remediation technologies, and site managers often must rely on information from technology vendors and predictive models, which may not accurately reflect the experiences of previous technology users. To help address these concerns, the U.S. Environmental Protection Agency (EPA) conducted an evaluation of data on historical costs of common remediation technologies. Cost curves were developed for four technologies, showing the relationship between cost for remediation and quantity of material treated. Although costs are known to be highly site‐specific and affected by many factors, the curves are useful in illustrating the variability of historical costs and the economies of scale for treating relatively large quantities of material. © 2002 Wiley Periodicals, Inc.     

A Preliminary Risk Assessment Protocol for Renegade Nanoparticles Deployed During Nanoremediation

The NanoRem European research project aims to support and develop the appropriate use of nanotechnology for contaminated land remediation by facilitating practical, economic, and exploitable nanotechnology for in situ remediation. This can only be achieved in parallel with a comprehensive understanding of the environmental risk‐benefit balance for the use of the nanoparticles (NPs) being investigated. While the NanoRem NPs could have a significant toxicity this is likely to be less potent than NPs currently being released into the environment, such as those from a variety of antibacterial products. The NanoRem NPs are likely to interact with the aquifer matrix, each other, and groundwater chemistry to rapidly cease to be mobile and are unlikely to penetrate into the aquifer more than a few meters from the point of injection. In terms of the source‐pathway‐receptor paradigm, the NanoRem NPs are cautiously presumed to represent a hazard (i.e., source). At least one receptor, in the form of not yet polluted groundwater, is present at all the NanoRem case study sites. While there are considerable uncertainties particularly with regards to the transport of NanoRem NPs, the ability of NPs to penetrate far into the formation is likely to be very limited. The relatively short travel distances reported in the literature for a variety of NP types and geological conditions suggest that the pathways are at best very limited in extent. Overall, this means that in many cases the level of risk renegade NPs can pose to the environment or human health is at most minimal. A qualitative protocol developed for the NanoRem field trials can demonstrate that injecting NanoRem NPs into contaminated groundwater poses a minimal level of risk due to the reduced pathway. ©2016 Wiley Periodicals, Inc.     

Accounting for Science and Uncertainty in Cleanup Levels: The Use of 1 μg/kg as the Cleanup Criterion for Dioxin in Soil

At hazardous waste sites, a 1 μg/kg (ppb) cleanup level has commonly been used for dioxin in residential soil. This article outlines reasons for the continued use of this value in site remediation. Dioxin, one of the most toxic compounds known, has been a focus of scientific study for many years. However, controversy continues to surround its regulation, with some scientists arguing that new scientific results support decreasing risk estimates for dioxin and others taking the opposite view. Part of this controversy appears to involve a decreasing emphasis on cancer and an increased concern about non-cancer and ecological impacts of dioxin. The 1 ppb soil cleanup level represents a reasonable generic value for dioxin, with higher or lower values required on a case-by-case basis to protect specific populations.     

梨园杀虫剂的环境风险评价

评价了某雪花梨栽培试验园区施用的杀虫剂对周围环境的风险性。其中包括;利用化学物质排毒系数评价法对梨园杀虫剂进行初步风险识别;非突发性水环境污染风险分析。采用瞬时点源一维河流模型对杀虫剂因事故性泄漏水体造成的风险进行预测;简要说明了杀虫剂进入土壤的途径及其对施药区和非施药区土壤的危害;采用高斯烟团模式,通过大气取样,对杀虫剂超常量喷施进入大气捕捞浓度分布进行统计分析,测算出杀虫剂在不同浓度范围出现的相对频率,从而鉴别其对居民点空气质量的危害几率。     

Accounting for Climate Change: Introduction

The assessment of greenhouse gases (GHGs) emitted to and removed from the atmosphere is high on both political and scientific agendas internationally. As increasing international concern and cooperation aim at policy-oriented solutions to the climate change problem, several issues have begun to arise regarding verification and compliance under both proposed and legislated schemes meant to reduce the human-induced global climate impact. The approaches to addressing uncertainty introduced in this article attempt to improve national inventories or to provide a basis for the standardization of inventory estimates to enable comparison of emissions and emission changes across countries. Authors of the accompanying articles use detailed uncertainty analyses to enforce the current structure of the emission trading system and attempt to internalize high levels of uncertainty by tailoring the emissions trading market rules. Assessment of uncertainty can help improve inventories and manage risk. Through recognizing the importance of, identifying and quantifying uncertainties, great strides can be made in the process of Accounting for Climate Change.     

Progress in Sustainable Remediation

In the past decade or so, management of historically contaminated land has largely been based on prevention of unacceptable risks to human health and the environment, to ensure a site is “fit for use” (i.e., achieves suitability for beneficial uses). More recently, interest has been shown in including sustainability as a decision‐making criterion. Sustainability concerns include the environmental, social, and economic consequences of risk‐management activities themselves, and also the opportunities for wider benefit beyond achieving risk‐reduction goals alone. This article provides a global roundup of progress by these initiatives and their key documentation. It reviews common themes and points of divergence. The information is based on a literature review and surveying the various networks involved, with a particular focus on recent developments in the United Kingdom. The global roundup updates a previous global roundup presented in Europe in 2013 at Aquaconsoil 2013 (Bardos et al., 2013a, 2013b). © 2014 Paul Bardos     

氯化亚砜生产的环境风险评价

用危险指数法对氯化亚砜生产过程各单元的风险性进行了评价,预测了制备锅爆炸事故的环境影响范围和程度。     

Resilience: A New Consideration for Environmental Remediation in an Era of Climate Change

There has been a growing movement within the environmental industry to develop more sustainable approaches in environmental remediation. These have generally included carbon footprint analysis, life cycle assessment, and best management practices to reduce the overall net environmental, social, and economic impacts of investigation and remediation activities. One of the foundational reasons net environmental impacts are currently evaluated is to identify and, subsequently, reduce contributions to climate change, primarily greenhouse gas emissions. While this trend toward sustainability and reduction in impact to the global environment is both important and admirable, the approach to remediation design and long‐term planning now needs to evolve further to better incorporate climate resilience into sustainable remediation design and implementation: designing remediation solutions that account for the projected impacts of climate change, as well as have the capacity to adapt to changing conditions. As a global population, we are now beyond the point of being able to prevent climate change and instead need to plan for adapting to it. In remediation, the effects of climate change create both risks and opportunities which should be considered during remedial design and long‐term planning. Responsible parties may see the push for—and management of—these considerations through their internal corporate risk management. The authors of this paper propose a simple framework for climate adaptation and resilience evaluations and plan development for remediation projects. ©2015 Wiley Periodicals, Inc.     

Remediation process optimization: A status report

There are hundreds of contaminated sites with remediation systems that require evaluation and modification to accomplish cleanup goals. These systems are operating well past projected cleanup schedules, cost more than projected to operate, and may not be as protective of human health and the environment as planned. Remediation process optimization (RPO) is an effective method to assess the progress of a system toward achieving cleanup goals within desired time frames and to make the necessary changes in order to reach those goals. Eight main components to the RPO process are evaluated during a review and an implementation plan of recommended changes to the system is developed. Follow‐up and tracking are essential to successful RPO programs. In this article, the authors present a summary of a recent Technical and Regulatory (TechReg) Guidance Document (Interstate Technology and Regulatory Council [ITRC], 2004) and related Technology Overview Series on Advanced Topics in RPO (ITRC, 2006) in a distilled form. © 2007 Wiley Periodicals, Inc.     

Actuarial Risk Analysis to Promote National Contingency Plan (NCP)‐Consistent Remediation

This article provides a case study of how green and sustainable remediation (GSR) concepts (including, but not limited to, worker risk) can be incorporated into the existing National Contingency Plan (NCP)/Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedy selection framework. The occupational risks of worker fatalities and injuries associated with two site remediation alternatives were calculated and compared. The results demonstrated that the increased worker risks associated with one of the remedy alternatives rendered it inferior based on the NCP “Balancing Criteria” of short‐term effectiveness. This type of approach is implementable at many sites by leveraging readily available information at the remedy selection stage using published methods and data sources. © 2014 Wiley Periodicals, Inc.     

用事故树分析法进行炼厂油罐爆炸事故的环境风险评价

论述了风险、风险评价、环境风险评价的概念及其主要内容，说明利用事故树分析法进行工程环境风险评价的程序和方法。并运用这种方法对某炼厂油罐爆炸事故进行了大气环境风险评价。     

Remediation of PCB-contaminated sediments: Volatility and solubility considerations

Through volatilization and long distance atmospheric transport, polychlorinated biphenyls (PCBs) have been redistributed throughout the global environment. Over the last 70 years, these compounds have permeated every known environmental niche including the remote polar regions of the globe. In this article, the solubility and volatility of the PCB congeners are reviewed relative to the remedial technologies that are currently in use or under consideration. The following discussion focuses primarily on the management options for PCB-contaminated, subaqueous solids that require removal, dewatering, drying, and other treatment to degrade the target contaminants and/or containment in engineered facilities including constructed islands, upland secure landfills and subaqueous pits. Environmental mobility resulting from natural and engineered processes is discussed in relation to the potential for contributing to the global loading and redistribution of PCBs. Additionally, select emerging technologies and management options are reviewed relative to their potential to produce secondary environmental impacts resulting from the soluble and/or volatile redistribution of PCBs. Based on a lack of long-term experience and the recognition that contaminants will remain unaltered for decades, technologies involving engineered containment structures should be considered temporary remedial measures until cost-competitive, destructive processing of contaminated sediments is feasible.     

Groundwater Remediation and Aquifer Clean-Up: A Case Study

Groundwater was being remediated with pump and treat technology at a facility where the groundwater was contaminated with commonly used degreaser solvents. Hydraulic conductivity of the heterogeneous residuum was beneficiated by applying pneumatic fracturing technology. The remedial system was controlled and monitored by a sophisticated remote telemetry system. A case history follows.