The dangers of leaking underground storage tanks
Oil spills from leaking underground storage tanks at homes and gas stations are the largest single threat to groundwater quality in the United States today.10 An estimated 1.2 million tanks nationwide, many of which were installed prior to new regulations in 1988, are a concern because tanks corrode quickly when buried unprotected in the soil. Corrosion, and other factors such as improper installation, spills during product delivery, and piping failures, have already caused more than 400,000 confirmed underground storage tank leaks nationwide.11
Petroleum products can contaminate water with chemicals that are very difficult to clean to drinking water standards. Gasoline spills are particularly troublesome. A 1998 survey by the DEC found that gasoline spills contaminated more than 800 private wells. Forty-seven public water supply wells in New York State were contaminated with the gasoline additive MTBE. This additive generally travels through groundwater faster than the rest of the gasoline components and is therefore an early indicator of contamination. The presence of MTBE at a site is estimated to increase cleanup costs by 20%-50%.12
The EPA estimates that cleanup of petroleum spilled underground could cost upwards of $32 billion. In New York State alone, DEC reports that in fiscal year 1999-2000 there were oil spills at more than 3,500 private homes, 1,000 gasoline stations and 1,200 other businesses.13 The Oil Spill Fund, administered by the Office of the State Comptroller, pays for cleanups and relocations in New York State. Since 1995, the Fund spent nearly twenty million dollars each year to clean up spills where a responsible party failed to perform the necessary cleanup. DEC estimates that these amounts represent only 5 to 10 percent of actual clean up costs for all spills statewide, since the majority of spills are cleaned up by the responsible parties, whose costs are not included in the total. Thus, oil spills in New York State probably cost over $200 million per year in cleanup costs alone. No one has tried to calculate the cost of potential human health or ecological injuries.