Under the petroleum cleanup program the Navy has been removing tanks and fuel lines and cleaning up spills and fuel leaks dating back to the early 1990s before the base closed. Most of the tanks and fuel lines were removed within three years after the base closed in 1997.
Cleaning up leaked and spilled fuel has been slower, often involving running a vapor extraction pump 24/7 for years. In a few cases, a groundwater contamination site will require a callback after the initial work is completed. The Navy’s routine monitoring of groundwater, even after cleanup work has been completed, is aimed at determining whether there is a rebound in contamination readings and follow-up treatment is necessary. Three such sites needing more work, on land recently acquired by the city, are currently undergoing follow-up treatment at the Navy’s expense.
Two of the sites once served as automobile service stations. The other site is where fuel was removed from planes before they were serviced.
The treatment method is simple. Air is pumped into the ground where the contamination is the highest. This causes the petroleum products to vaporize, and then a suction system draws out the vapors into a barrel of charcoal. The air injected into the ground also helps natural petroleum-digesting bacteria to grow.
Solar-powered cleanup for the first time at Alameda Point
Air injection/extraction pumps at the two former service station sites are running on electricity from the grid. At the former plane de-fueling site next to Building 410, however, the Navy is using a solar-powered pump for the first time anywhere at Alameda Point. Derek Robinson, the Navy’s Environmental Coordinator, explained the solar choice saying, “Electricity is not optimum because the overhead electrical tie-in is located too far away for the system to be tied in to the grid cost effectively. The solar units provide the power necessary to operate the air sparging and soil vapor extraction system at a competitive price.” The only other option was a combustion engine pump running on gas or diesel.
“The battery storage system is traditional lead/acid batteries,” said Robinson. “The solar array charges storage batteries allowing the system to store energy and operate in cloud cover and beyond strictly daylight hours; however, the system is designed to power off the blowers once the voltages drop below a preset level,” he said.
Sustainable Technologies, located just a block away at Alameda Point, constructed the entire rig. It consists of solar panels, a box full of lead-acid batteries, a circuit panel, and a pump. Ironically, Sustainable Technologies is located on a Superfund site that will take another six years to clean up.
The area next to Building 410 where the fuel spills occurred has had a number of cleanup actions going back to 2002. “Corrective actions under the petroleum program were conducted in 2002 and 2011 and a remedial action under the CERCLA [Superfund] program was conducted between 2005 and 2006,” said Robinson.
Work will continue until the end of the year. The Navy will always be responsible for returning to do more cleanup work if groundwater testing shows some of the contamination was missed.
Locations of three petroleum cleanup sites currently undergoing more cleanup work.