	Most Tanks Have Been Upgraded, but Many Are Not Properly Operated and Maintained

Based on state responses to our survey, we estimated that nearly 617,000, or about 89 percent of the approximately 693,000 regulated tanks, had been upgraded with the federally required equipment by the end of fiscal year 2000. However, another five states reported that at least half of their non-upgraded tanks were still in use. EPA and states assume that the tanks are empty or inactive and therefore pose less risk. According to our survey results, some states and EPA regions would need additional staff to conduct more frequent inspections. Some Tanks Continue to Leak Even After They Have Been Upgraded, Although the Extent of this Problem is Unknown

In fiscal year 2000, EPA and the states confirmed a total of more than 14,500 leaks or releases from regulated tanks, although the Agency and many of the states could not verify whether the releases had occurred before or after the tanks had been upgraded. EPA, as one of its program initiatives, is working with the states to gather data on leaks from upgraded tanks in order to determine whether equipment requirements need to be strengthened, such as requiring double-walled tanks. In closing, the states and EPA cannot ensure that all regulated tanks have the required equipment to prevent health risks from fuel leaks, spills, and overfills or that tanks are safely operated and maintained.
Why GAO Did This Study

Hazardous substances that leak from underground storage tanks can contaminate the soil and water and pose continuing health risks. Leaks of methyl tertiary butyl ether--a fuel additive--have forced several communities to close their wells. GAO surveyed all 50 states and the District of Columbia to determine whether tanks are compliant with the Environmental Protection Agency's (EPA) underground storage tank (UST) requirements.

What GAO Found

About 1.5 million tanks have been closed since the program was created, leaving about 693,000 tanks subject to UST requirements. Eighty-nine percent of these tanks had the required protective equipment installed, but nearly 30 percent of them were not properly operated and maintained. EPA estimates that the rest were inactive and empty. More than half of the states do not meet the minimum rate recommended by EPA for inspections. State officials said that they lacked the money, staff, and authority to conduct more inspections or more strongly enforce tank compliance. States reported that even tanks with the required leak prevention and detection equipment continue to leak, although the full extent of the problem is unknown. EPA is seeking better data on leaks from upgraded tanks and is considering whether it needs to set new tank requirements, such as double-walled tanks, to prevent future leaks.