------- If LNAPLs and DNAPLs are not removed, they The current recognition of the limitations of pump- serve as on-going sources of contamination. and-treat technology has led to EPA interest in However, DNAPLs can be extremely difficult to improving the efficiency of extraction systems, as well locate and their migration pathways difficult to as increasing development and application of in situ determine. If present, current application of pump- treatment technologies. The Technology Innovation and-treat systems may not achieve projected clean- Office (TIO) conducted a study inventorying research, up goals or meet anticipat- ed remediation schedules. Where the above cases do not exist, current use of pump-and-treat tech- nology can be effective in reducing contamin- ant levels to the remed- ial objectives. It also can be highly effective in con- taining contamination. Occurrence of Contaminated Ground Water at NPL Sites * Sites with no ground- water contamination Sites with ground- water contamination (other media ato contaminated) * NPL Characterization Project, EPA/640/841/069, November 1991 laboratory studies, and field demonstrations of in situ treatment for contaminated ground water. The study concluded that there are large gaps in both in situ technologies available for ground-water remediation and research in developing and evaluating new in situ treatment technologies for ground water. RESEARCH AND DEVELOPMENT Coal Higher priority for research and development of in situ ground-water treatment technologies is needed to produce new technologies that will be more effective and achieve cleanup faster than current technologies. Synopses of Findings A current inventory shows that only 15 technologies to supplement or improve pump-and-treat remedia- tion are in the research and development stage. Most of these technologies have entered, or are ready to enter, the "controlled field experiment" stage of development. Field studies provide the quantitative information that is needed to move the technologies forward to full-scale demonstrations and eventual applications. In situ systems require an in-depth understanding of the subsurface not required with ex situ systems. Site characterization for a field experiment or demon- stration of an in situ technology must be comprehen- sive, but even thorough characterization of a con- taminated site produces contaminant mass estima- tions with wide error margins. Without accurate knowledge of the contaminant mass in the aqui- fer, it is difficult to determine the effectiveness of a technology. Because of these limitations, experimental sites where contaminants may be introduced are needed to determine a technology's effectiveness. Sites with existing contamination, where researchers can participate in site characterization, are also needed to demonstrate in situ technologies. In addition, there is no central repository where research information is stored. Users are not aware of technology development and researchers are not aware of gaps that exist in current research. Strategic Objectives Q Investigate the availability of field research sites, similar to the Borden Canadian Forces Base, where contaminants may be introduced. Q Increase the number of demonstrations of in situ treatment technologies for ground water on existing waste sites. Q Prioritize research needs. Q Improve communication between technology users and researchers. ------- REGULATIONS Goal To reduce barriers to research, development, and application, State and Federal regulations that are identified as impediments need to be examined. Synopses of Findings Workshop participants identified State and Federal regulations as impediments including: 1) regula- tions that do not allow reinjection; 2) enforce- ment of water quality standards, which serve as barriers to injection of substances (such as ni- trates) that could augment in situ bioremedi- ation; 3) "No Degradation" policies, which may not allow for the use of Alternate Concentra- tion Limits (ACLs) for ground-water cleanup; and 4) the use of Drinking Water Standards as Applicable or Relevant and Appropriate Requirements (ARARs) in Superfund. Strategic Objectives Q Provide a forum for State and Federal regula- tors to discuss the evaluation of the injection of surfactants, co-solvents, nitrates, and other sub- stances that will assist in cleanup of ground water. G Provide regulators guidance and protocols in technical areas of concern, such as hydraulic control in the area of injection and fate of in- jected substances. Q Open a dialogue between concerned parties about the limitations of current and developing technologies and achievable cleanup standards. APPLICATION Goal Increase in the selection and use of innovative treatment technologies for remediation of contaminated ground water requires incen- tives for technology users, reduced risk of failure, and better understanding of the limitations of existing technology. Synopses of Findings A few in situ treatment technologies have been applied full-scale to ground-water cleanup. They include in situ bioremediation with oxygen enhancement by hydrogen peroxide and air sparging. Application to contaminant cleanup at sites regulated under other authori- ties is possible, but, to date, only 12 Superfund RODs have selected an innovative in situ technology for ground-water remediation. There are no incentives to use an innovative technology because cleanup criteria may not be met and containment by pump-and-treat methods would still be needed. Lacking adequate performance data, Federal and State regulators are willing to approve long term pump-and-treat systems to contain the contamination, rather than apply a new technology that may not meet cleanup goals. Engineers prefer ex situ systems where treatment variables, such as temperature, volume, and duration, can be controlled. Strategic Objectives Q Educate stakeholders on in situ ground-water technologies and the limitations of current technologies. Q Collect and standardize cost and performance data by evaluating full scale applications and eventually produce design manuals. Q Reward those who take the risk of using in situ treatment systems. ------- PUMP-AND-TREAT TECHNOLOGY Coal The cost and performance of pump-and-treat technology currently in use must be determined in order to serve as a benchmark for comparison of in situ treatment technologies. Synopses of Findings For in situ treatment to be routinely considered as an alternative or enhancement to pump-and-treat, it must prove to be more effective, less costly, or more timely in remediating aquifers. However, there is little published information concerning the costs and efficiency for current technologies. Many users are unsure of what the total costs will be for current pump-and-treat systems and have no benchmark for comparison against the costs of alternative technologies. Strategic Objectives Q Establish a record of capital, operating, and maintenance costs for current pump-and-treat technology use. Q Determine the actual effectiveness of pump-and- treat technologies as they are currendy used. INFORMATION SHARING Coal Increase the communication between ground- water professionals, researchers, regulators, site managers, and industry by more widely disseminat- ing concise technology information for in situ ground-water treatment. Synopses of Findings Technology users and regulators have many questions about new or innovative in situ treat- ments for ground water. To foster an environ- ment of acceptance for in situ technology, technol- ogy users and regulators need information that is targeted towards resources they use. Strategic Objectives Q Track in situ applications of treatment technologies. Q Improve information distribution to State agencies and Federal facilities. Q Encourage innovative technology advocacy in States, EPA Regions, other Federal agencies, and professional societies. Q Assess users' information needs for in situ treat- ment technologies. Q Target information sources relied upon by users. BIBLIOGRAPHY In Situ Treatment of Contaminated Ground Water: An Inventory ofResearch and Field Demonstrations and Strate- gies for Improving Ground-Water Remediation Technologies, U.S. EPA, (Available through the Technology Innovation Office), September, 1992. Considerations in Ground-Water Remediation at Superjund Sites and RCRA Facilities—Update, Directive 9283.1-06, U.S. EPA, Office of Solid Waste and Emergency Response (OSWER), May 27,1992. Evaluation of Ground-Water Extraction Remedies: Phase II, Volume 1, Summary Report, Publication 9355.4-05, U.S. EPA, Office of Emergency and Remedial Response (OERR), February, 1992. ^ The mission of EPA's Technology Innovation Office (TIO) is to increase government and industry applications of innovative treatment technologies to contaminated waste sites. To obtain additional information regarding the use of innovative treatment technologies, contact the Technology Innovation Office (TIO) at (703) 308-8800 or write: U.S. Environmental Protection Agency, Technology Innovation Office, 401 M Street, S.W. (OS-HOW), Washington, DC 20460 tftt'^^^ This document is not intended to and does not constitute any rulemaking, policy or guidance by U.S. EPA, and cannot be relied upon to create substantive or procedural right enforceable by any party. ------- |