Summary: The quality of the nation's waters has improved since the Clean Water Act was revised in 1972. The act bans facilities from discharging pollutants in amounts exceeding those authorized in their discharge permits. But GAO's analysis of the Environmental Protection Agency's (EPA) compliance data for fiscal years 1992-94 shows that major facilities often violated their permits. For fiscal year 1994, for example, about one in six of the nation's 7,000 major regulated facilities significantly violated the discharge limits in their permits. However, EPA believes that the actual number of major violations of discharge permits may be nearly twice as high as the compliance data suggest. In addition, violations that EPA has not identified may be as serious from an environmental perspective as those that it has identified. EPA does not identify all significant violations of discharge limits because its criterion for screening violations has not remained consistent with the types of discharge limits used in permits. In September 1995, EPA expanded its criterion for identifying cases of significant noncompliance and, hence, for assigning enforcement priorities.
