While they are all inactive by now, as their average life span was only 15 to 25 years, there are still thousands of underground oil tanks in the region. In Oak Bay, the fire department’s records show ...

FILE - Workers remove a 10,000-gallon underground gasoline storage tank to be replaced with a new tank at a gas station in Sacramento, Calif., May 23, 2003.

In Oak Bay, the fire department’s records show the municipality had approximately 1,800 underground oil storage tanks in residential properties as of 1998, the last time a review was undertaken.

FILE - Workers remove a 10,000-gallon underground gasoline storage tank to be replaced with a new tank at a gas station in Sacramento, Calif., May 23, 2003. Nearly half of Americans depend on ...

FILE - Workers remove a 10,000-gallon underground gasoline storage tank to be replaced with a new tank at a gas station in Sacramento, Calif., May 23, 2003. Nearly half of Americans depend on ...