During the last ten years, the nation has become increasingly aware of the potential for environmental damage from leaks in underground and aboveground storage tanks, and related pipelines. Federal and state regulations have been developed that mandate inspections, require regular testing and set out design standards of construction for underground storage systems. More specifically, existing federal regulations (40 CFR Parts 280 and 281, September 1988) require that underground tanks and pipelines containing petroleum products and other hazardous substances be tested for leaks on a regular basis and that once a leak has been detected, it be corrected. While this requirement appears to be relatively simple, it, in fact, presents substantial difficulty in implementation. The difficulties are of two types.