Safe Drinking Water Act:

Improvements in Implementation Are Needed to Better Assure the Public of Safe Drinking Water

GAO-11-803T: Published: Jul 12, 2011. Publicly Released: Jul 12, 2011.

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David C. Trimble
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Office of Public Affairs
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This testimony discusses highlights of GAO's report on the Environmental Protection Agency's (EPA) implementation of requirements for determining whether additional drinking water contaminants warrant regulation. The number of potential drinking water contaminants is vast--as many as tens of thousands of chemicals may be used across the country, and EPA has identified more than 6,000 chemicals that it considers to be the most likely source of human or environmental exposure. The potential health effects of exposure to most of these chemicals, and the extent of their occurrence in drinking water, are unknown. Under 1996 amendments to the Safe Drinking Water Act, every 5 years EPA is to determine for at least five contaminants whether regulation is warranted, considering those that present the greatest public health concern. EPA issued final regulatory determinations in 2003 and 2008 on a total of 20 contaminants, deciding in each case not to regulate. EPA did not recommend any new contaminants for regulation until February 2011, when it reversed its controversial 2008 preliminary decision to not regulate perchlorate, an ingredient in rocket fuel and other products. This statement summarizes our report being released today that (1) evaluates the extent to which EPA's implementation of the 1996 amendments has helped assure the public of safe drinking water and (2) reviews the process and scientific analyses EPA used to develop the 2008 preliminary decision to not regulate perchlorate..

EPA has not effectively implemented the 1996 amendments' requirement to consider, for regulatory determinations, contaminants that present the greatest public health concern. The contaminant candidate list that the amendments require EPA to develop every 5 years represents one level of prioritization as EPA selects from a larger universe those contaminants the agency believes warrant consideration for regulation. However, EPA officials told us that its Office of Water, which has primary responsibility for implementing the requirements of the Safe Drinking Water Act, has not (1) further ranked or otherwise prioritized the contaminants on the list on the basis of public health concern or (2) prioritized contaminants on the basis of public health concern when selecting them for regulatory determinations. For 16 of the 20 regulatory determinations made through January 2011, EPA based its decisions to not regulate on its assessment that public exposure to these drinking water contaminants was minimal--that is, there was limited or no occurrence of them in public drinking water systems. An EPA official described these determinations as addressing the "low hanging fruit"--rather than the contaminants of greatest public health concern. Overall, data availability--not consideration of greatest public health concern--has been the primary driver of EPA's selection of contaminants for regulatory determinations. In contrast to EPA's usual regulatory determination process, which is managed by a work group of professional staff with relevant expertise from across the agency, EPA officials decided that the agency's continuing deliberations on perchlorate would be managed by a less inclusive, small group of high-level officials, such as the Deputy Administrator and several Assistant Administrators. Notably, EPA did not include the Office of Children's Health Protection in its small group despite EPA's and the National Academies' conclusion that iodide uptake inhibition from perchlorate exposure had been identified as a concern in connection with increasing the risk of neurodevelopmental impairment in fetuses of pregnant women with iodine deficiency and to developmental delays and decreased learning capability in infants and children. This group of high-level officials managed the regulatory determination process for perchlorate both within EPA and externally with the Perchlorate Interagency Working Group, whose work was coordinated by the Council on Environmental Quality. According to an EPA briefing document, the Perchlorate Interagency Working Group was established in 2002 "to identify and help resolve perchlorate science and science policy issues."

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