The US Navy is preparing to replace storage tanks that have leaked approximately 1.5 million gallons of fuel into the ground at Point Loma Naval Base.
The $140 million (101 million) replacement project will last five years, involving the construction of eight aboveground tanks at the base's Defense Fuel Support Point – the largest naval fuel depot in the world. Some tanks are years past their expected life span, with 54 needing replacement.
Between 1999 and 2003 oil leaked from three tanks. The spillage reached about 50 feet below ground. The Navy began its cleanup work in 2001, with a possible further 20 years until completion. The Navy has spent nearly $60 million to repair the leaks, map the underground plume and clean up the site. Only about 10% of the leaked fuel has been recovered.
The new tanks will be installed at the same site as some existing tanks. Combined capacity is 42 million gallons of jet and marine diesel fuel for military ships and aircraft at facilities throughout the region.
In September, contractors started digging an 800 ft gravel-filled trench near the existing tanks to speed up the recovery. Forming the trench will cost $3.5 million. The tanks will be circular and double-walled, featuring monitors designed to detect leaks and track fuel movement in and out of them with improved volume controls. Workers also will build four catch basins around the replacement tanks to capture rainfall runoff and fuel spills.
The Navy's plan also includes construction of a facility near the tanks to recover oil from the bilge water of its ships. The current plant is 30 years old.
Navy officials are expected to choose a contractor for the tank-replacement project in spring 2008, with construction starting later in the year. When work is finished, the new fuel tanks will occupy 35 acres on the base instead of the current 200.