This leakage can come from underground or damaged aboveground tanks. The chances of a leak occurring increase dramatically when tanks are poorly maintained or more than 15 years old. Spills can also occur when tanks are being filled. It takes very little fuel to contaminate groundwater. A 1-gallon spill can contaminate a million gallons of water to the point where odor and taste make it unacceptable to drink.
Fuel oil contains a number of potentially toxic chemicals.
Once groundwater is contaminated, it is very difficult and expensive to clean up. There are many ways to ensure that your aboveground or basement tank does not leak. The first and foremost is to be sure the tank is on solid, stable footings that resist movement from changes in soil moisture and frost heaving. Brick, cinder block and concrete are the most common materials for footings. Place a waterproof layer under the fill pipe to prevent small spills from reaching water supplies.