andvuhe&ll ' 'ty to contamination of -water resources, EFA is planm g to adopt a dif€emtialprotection policy. Early in 1987, the agency intends to issue groundwater classification guidelines that will provide a framework for imple-g the policy. Theguidelineswill be structuredto pmtea the most valuable and useful groundwater supplies, given limited availableresources. The guidelies also should help to define underground l e ' thatcanbeusedsafelyasreposfor hazardous wastes.
well injection of hazardous wastes, a disposal method for which EPA promulgated regulations in 1980 under the Safe Drinking Water Act. These are the underground injection controls (UIC). The Hazardous and Solid Wastea Amendments of 1984 direct the EPA administrator to reevaluate the practice by Aug. 8, 1988, to determine w h e k the ban on land disposal of hazardouswastes should be extended to deepwell injection. In anticipation of this deadline, a 1986 study pqared for the Underground Injection Practices Council found that during the 25 years this d o d has been in use, approximately 9% of the. 500 Class I wells (wells injecting wastes below an underground supply of drinking water) experienced malhctions. Five wells had malfnnctions that multed in contamination of underground drinking-water supplies. These leaks were cleaned up, and no adverse health effectshave been attrib uted to these system failures. Most of the mallimctions occurred in the injection wells of older design. Indications are that wells of newer design, with improved monitoring systems and responsive preventive maintenance, will substantially reduce the incidence of well malfunction and resulting contaminant discharges, although there are not sufficient long-term data available to verify this. The 1980 UIC regulations provide for improved data collection and record-keeping to evaluate problems and advances in technology and procedures. When malfunctions occur,these data may be invaluable as a basis for furtherdesign improvements. EPA may want to umsider including similar performance data requirements in its underground storage tank program regulations to enhance continuous system improvementsand reduce ris ronmentaldamage.
agency and the public, addresses leaking undergmund storage tanks. In a 1986 EPA study, 433 underground fuel tank systems were tested to estimatethe percentage of leaking systems in a nationwide population of abwt 750,000 such systems. Under test conditions, an estimated 35% of nonfarm systems leaked at an average rate of 0.32 gaYh (9 million barrels of fuel per year). Further, the study indicated there is little difference in either the leak rate or percentage of systems leaking, regardlessoftheageofthetankS,coasaUction material (steel or glass fiber), or whether the steel tanks were cathcdid y protected. In addition, it found that only 2.3%of the leak rate could be attributed to distribution systems (valves and pipes). There are qnestions about the comparabiity of the test method to actual operatiag conditions that could not be directly answered from the test data. Proponents of glass fiber and cathcdically proteaed steel tanks feel there is insufficient quantity or duration of containment performance data to conclude that these systems perform no better than the unprotected steel tanks generally used in older systems. Because of uncertainties associated with the test method and the apparent lack of data to verify that one or more @bnologies provide superior containment capabiity, EFA is finding it difficult to determine what regulatory ap pmach to adopt.
Undergmind storage tanks The program that has m n t l y received the most attention, from both the
Richard M. Dowd, Ph.D., is a Msh-
underground water ly extends to deep
government official. Congres has enacted lited groundwater protection provisions in various statutes administered by EPA. Under Sections of the Safe Drinking Water Act (SWDA) and the Hazardous and Solid Wastes Amendments of 1984 (which amend the Resource Conservation and Recovery Act of 1976), EPA has several prcgrams that deal with undergmund water contamination. These include
, Teohml.. W. 20,No. 9, lSaa
ingtm. D.C., consulta?U to Environmentnl Research & B&logy, Inc.
