The greatest cost is to replace underground tanks, which can run about $30,000 each at a small station.
The spring kept 21 underground tanks filled with over half a million gallons of water.
It isn't even necessary to remove an underground storage tank.
The water was contaminated years ago by the company's underground storage tanks.
Six years earlier an underground storage tank was found to be leaking.
Homeowners who do not have insurance on their underground tanks, however, face a far more uncertain future.
A company builds a gas station, with underground tanks to store the fuel.
"Now, with the companies we represent, not one will write a new policy that covers an underground storage tank."
The waste, held in 51 underground tanks, will be somewhat concentrated by chemical means.
The county estimates that up to 25 percent of the more than 30,000 residential underground tanks now in use are leaking or will be soon.