INTEGRATED FRAMEWORK FOR ASSESSMENT OF
SITE REMEDIATION OPTIONS
James L. Regens and Donald G. Hodges
Tulane University Medical Center
Patrick Wilkey and Eric Zimmerman
Argonne National Laboratory
Anthony Armstrong
Oak Ridge National Laboratory
Linda Kelley
CB Consulting
Timothy A. Hall
ManTech Environmental Corporation
Eugene A. Hughes
Erin Engineering and Research, Inc.
ABSTRACT
The Consortium for Environmental Risk Evaluation (CERE) has designed an integrated Technology Evaluation Framework to help environmental managers select and deploy remediation technologies, The Technology Evaluation Framework allows managers to identify and systematically compare conventional and innovative remediation technologies to assess site remediation options. The Framework integrates eight criteria that are relevant to the technology selection and deployment decision in order to assess site remediation options.
INTRODUCTION
Environmental managers address a complex interplay of factors when selecting site remediation options to meet the requirements of various health and environmental regulations. Specific objectives that influence selecting a remedial alternative include: managing risks; reducing costs; protecting worker health and safety; minimizing generation of waste; creating a collaborative relationship with regulators and stakeholders; focusing technology deployment on cost and risk reduction; and integrating waste treatment and disposal across sites. The final site management decision involves difficult trade-offs among these conflicting concerns, and each requires an understanding of the site and the remediation technology's attributes (National Research Council 1997, 1996; U.S. Environmental Protection Agency 1996; U.S. Congressional Budget Office 1995; U.S. Office of Technology Assessment 1991).
As shown in Fig. 1, the Technology Evaluation Framework can be used during the technology screening or alternatives evaluation stages of the CERCLA Remedial Investigation/Feasibility Study (RI/FS) process. In the technology screening stage, the Framework enables environmental managers to quickly identify data gaps. These gaps can be filled during the RI/FS process, and the Framework can be used again at later stages of the remedy selection process. The summary results from the Framework help ensure that potentially useful solutions are not missed and that the value of the available information base for decision-making purposes is maximized. The RCRA Facility Investigation/Corrective Measures Study (FI/CMS) process is similar to the RIFFS process, and the Framework can be used to compliment these processes to ensure the credibility and reproducibility of the technology evaluation results. Because RCRA corrective actions are often time-sensitive, the CERE Framework allows managers to quickly evaluate technologies or remedial alternatives and to spend their available time evaluating the more promising alternatives. At a site pursuing voluntary compliance, environmental managers and regulators may be more willing to consider new technologies meeting desired end uses. The Framework provides a means for establishing credibility and characterizing applicable technologies in these cases.
Figure 1. Generalized Remedy Selection Process Applicable to CERCLA, RCRA, or Voluntary Cleanup
OVERVIEW OF THE TECHNOLOGY EVALUATION FRAMEWORK
The Technology Evaluation Framework provides a comprehensive, consistent method for selecting environmental technologies and developing alternative remediation strategies to address site restoration problems at CERCLA, RCRA, and voluntary compliance sites. In developing the Framework, four key issues were considered:
To meet these challenges, the Technology Evaluation Framework was developed to help environmental managers assemble and synthesize information to evaluate and compare conventional and innovative remediation technologies. Based on the decisions that environmental managers must make and the challenges they confront, the Technology Evaluation Framework is sensitive to three key design objectives (1) use comprehensive and consistent criteria; (2)delineate information gaps and uncertainties; and (3)provide compatibility with other management tools, when appropriate, to support setting priorities and planning processes. The Technology Evaluation Framework provides a comprehensive and consistent basis for the evaluation and comparison of technologies and promotes interactive communication about remedial options. It can be used both for evaluative purposes and as a communication tool to help initiate and focus a dialogue between the environmental manager and a variety of interested stakeholders. Additionally, it can be used to provide sufficient documentation to inform other remediation managers facing similar contamination problems. The Framework also can be used to provide a baseline against which remedial actions can be reassessed as new information becomes available about conditions at a site or about a technology.
The Technology Evaluation Framework was developed from an extensive dialogue with environmental managers, supplemented by the experience of individual team members and reviews of completed technology selection and deployment activities. As shown in Fig. 2, the Technology Evaluation Framework incorporates eight criteria that influence the selection of site remediation options. Because an individual criterion may carry varying degrees of importance at various sites, the Framework allows environmental managers to use the criteria with their own set of site-based influences (i.e., weights). As a result, the practicality of technologies to address site cleanup problems can be assessed comprehensively. The documented, reproducible evaluation allows environmental managers to make comparisons of remediation technologies on a consistent basis.
Figure 2. CERE Technology Evaluation Framework Criteria
The technical performance of a technology is of great importance to an environmental manager because the technology must be effective to achieve the site cleanup goals and be accepted by the regulators and the community. Technical performance is evaluated on the basis of four indicators: effectiveness, readiness, implementability, and reliability. Effectiveness measures the ability to meet the remediation goals for the site. Readiness measures the probability that a technology can be deployed at a particular site to resolve a particular site contamination problem. Implementability measures potential impact of engineering requirements on the practicality of applying a technology under site-specific conditions. Reliability measures the proportion of the time the technology or remedial system is likely to be operational at capacity.
The second criterion incorporated into the Framework provides a common life-cycle cost basis for the meaningful comparison of technologies by using documented estimating principles to divide cost into management and integration (M&I) costs, capital costs, and operations and maintenance (O&M) costs. The life-cycle cost of a technology incorporates the funds required to design, mobilize, deploy, maintain, operate, and demobilize a technology over the time period for which the cost of implementing a technology accrues.
Many technologies and associated cleanup processes generate waste-stream by-products, or residuals. The determination of the by-products of a particular technology choice is important because the by-products influence the overall ability to maintain and control hazardous or acutely hazardous substances in an appropriate manner. The process residuals indicator, existing system capacities, is evaluated on the likelihood that process residuals generated by technology deployment will not require modification of the existing waste-management systems.
Regulatory feasibility, the relative degree of difficulty or ease in securing administrative or regulatory approval of a technology, is an important criterion in the overall evaluation process for selecting and deploying a technology at a particular site. The Framework employs two indicators for regulatory feasibility: permitting experience and the need for permit modifications. Permitting experience is directly relevant because permitting requirements significantly contribute to the schedule and level of management associated with the deployment of a particular technology. The second indicator for regulatory feasibility is permit modifications that may need to be considered to handle process residuals. Residuals require additional handling and may require a combination of additional treatment, interment, or removal from the site. Residuals also can trigger additional regulatory requirements due to land disposal restrictions at the receiving site.
The risks associated with a remediation technology may be an important factor in the decision to select and deploy that technology, because health and safety impacts can vary substantially for workers, the public, and the environment (National Research Council 1995). The Technology Evaluation Framework divides the risk associated with a remediation technology into two categories: relative risk reduction and risks during deployment. Relative risk reduction is defined as the difference between baseline risk and risk at a site after technology deployment. Deployment risks are those risks that are potentially encountered during remediation of the site. Deployment risk is represented by indicators for exposure, transportation, and site safety risk. Three target receptors—workers, the public, and the environment--are evaluated for each indicator of deployment risk.
Environmental technologies need to be evaluated in terms of their potential impact on future land use. The reuse of the remediated site is dependent on a number of factors, including the technology employed and the type of contamination involved. Understanding the restrictions placed on reuse by technology deployment will be important in deciding whether the technology has long-term management implications, as well as the associated value limitations and acceptability to stakeholders of an unusable site.
Although the assessment of ecological risks associated with a technology's use captures most of the impacts to the natural system, the potential to ameliorate or exacerbate existing natural resource damages at a site requires additional evaluation. Natural resource damage mitigation, as a technology selection and deployment indicator, is assessed in terms of the extent to which deployment of a technology reduces the existing damages to natural resources or ecosystems in the site area.
The Technology Evaluation Framework recognizes the importance of stakeholder input. An initial evaluation of stakeholder concerns, as revealed by prior experience, is useful for alerting environmental managers to possible issues (National Research Council 1997). Examples of important stakeholders include Native American tribes, state and local governments, workers, citizen activist groups, and site advisory boards associated with government installations. Stakeholders' concerns may vary depending on conditions at a particular site and can change over time. The indicators for stakeholder concerns - performance, cost, risk, process residuals, natural resource damages, environmental justice, and tribal issues - are evaluated based on issues raised in prior deployments.
APPROACH TO FRAMEWORK APPLICATION
The Technology Evaluation Framework is flexible in the method and timing of its application. It may be used at multiple stages of the technology selection and deployment process. The quality of the technology evaluation is a function of the quality of the data and information inputs at the time of application. Under some circumstances, an environmental manager might decide to use the Framework in an iterative fashion to screen technologies. With an iterative approach, the manager would array the criteria into a series of tiers. Fig. 3 depicts examples of such a tiered approach in which the eight criteria have been divided into three tiers. In the first example, an environmental manager can first identify those technologies that have favorable performance indicators. At the second stage of the tiered approach, technologies that rate well for the specific site and contamination conditions are then evaluated in terms of life-cycle cost, risk, and process residuals. The technologies that prove favorable for these parameters are further evaluated in the third tier. The third tier focuses on permitting issues, stakeholder concerns, and post-remediation impacts. Specifically, technologies that are favorably evaluated in the first two tiers would be evaluated for effects on future land use, natural resource damage, regulatory feasibility, and stakeholder concerns. A tiered approach also may be structured to focus on reaching final end states when life-cycle costs is a major constraint.
Figure 3. Examples of Tiered Application of Technology Evaluation Framework
It is important to interweave public interaction throughout each tier of evaluation, especially for public agencies responsible for site restoration activities. The basis for stakeholder concerns may parallel the evaluation criteria in the Framework and needs to be discussed with the public as the decision-making progresses. As an environmental manager proceeds through each step of applying the tiers, new sets of concerns may be identified. Those concerns can provide a basis for discussion with the site-based stakeholders while the environmental manager interacts with them during the remedy selection process. Each tier may identify a different set of concerns that may need to be addressed in stakeholder interactions. In addition, depending on the local context, concerns about environmental justice and tribal perspectives may require consideration at each of the tiers. By interacting with the public while progressing through the tiers, the remediation manager is likely to develop a better understanding of the stakeholder concerns, provide meaningful information to the stakeholders, and receive stakeholder feedback regarding these issues throughout the technology selection and deployment process.
BENEFITS OF USING THE TECHNOLOGY EVALUATION FRAMEWORK
The Framework helps environmental managers identify data needs associated with the technology and determine where the technology would require more development prior to deployment at a particular site. By synthesizing data needs, it is possible to ensure that research and development (R&D) is targeted to overcome shortfalls in meeting site-specific goals. Environmental managers also benefit from visualizing estimates of funding requirements throughout the years of remediation and from identifying issues for discussion with appropriate stakeholders prior to final cleanup decisions.
Stakeholders, regulators, and technology developers benefit because the synthesis of the Framework results provides a clear presentation of the technology attributes and how those attributes contribute to selection and deployment of a technology to resolve site-specific remediation issues. With this information, all involved parties can focus on the important issues of interest.
Because the Framework documents the permitting history for a remediation technology or the need for permit modifications to deal with the technology's process residuals, discussions with regulators can occur on a common basis. Regulators can identify how technical performance is anticipated to affect the existing contamination and how risk is anticipated to be reduced by deploying various technologies. Technology developers and owners derive benefit because the evaluation of their technologies can provide an indication of where the technology needs improvement as well as the level of improvement required to be competitive with other options to address contamination problems at specific sites.
Output from the Technology Evaluation Framework provides a baseline against which technology selection and deployment decisions can be reassessed by factoring in new information. As new information becomes available, revising the data originally included in the Framework can help an environmental manager evaluate whether altering the method of deployment or extent of use of a technology is desirable.
The Framework can be used by environmental managers to initiate and focus a dialogue between the environmental manager and a variety of stakeholders. This may help managers avoid unnecessarily narrowing options or becoming too committed to a particular course of action before involving all interested parties. Such a dialogue potentially can increase the accuracy and completeness of the information on which the evaluation is based; help ensure that the full range of relevant factors is taken into account; and increase the likelihood that final choices are acceptable and, therefore, implementable.
ACKNOWLEDGMENTS
Managed by Tulane University, the Consortium for Environmental Risk Evaluation (CERE) is a partnership, involving an integrated team of experts from universities, national laboratories, and consulting firms, established in 1994 under DOE Cooperative Agreement #DE-FC01-94EW54102. The CERE program is funded by the DOE Office of Environmental Management (EM) and directed by Dr. James L. Regens of Tulane University Medical Center. These opinions do not necessarily represent the official position of the federal government or DOE.
REFERENCES
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