Capt. Mark Patton, commanding officer at Naval Base Point Loma, has confirmed that traces of fuel product from a large plume have been detected in La Playa.
The discovery came a little more than a week after the Navy placed two investigation wells on private property about 10 feet from the federal property line. Until the announcement, officials thought the product was contained on military land.
Initial data show product at the site to be a few inches thick at a depth of up to 50 feet below the surface. Patton estimated that the “thin extension,” or finger, branching from the larger body of the plume could be up to 60 feet wide.
Patton said that preliminary data from the wells do not always offer the best picture and typically show more product than is actually there.
Laurie Walsh, engineer for the San Diego Regional Water Quality Control Board, oversees the Navy’s progress on the matter for the state and agreed that weeks of readings from the wells are necessary to show the true fuel level there.
“Initially, you can get a build-up of fuel, and at times it can be higher than what would be seen in the aquifer itself,” Walsh said. “It’s not an exact science; it’s estimation.”
Regardless of how accurate the early findings prove to be, Patton said he preferred to take what information he had to the public immediately.
“We wanted to put out preliminary information that we had and not keep that from public knowledge because we knew there was a strong public interest,” he said.
Within a day of receiving the results from a Navy contractor, Patton noticed District 2 Councilman Kevin Faulconer and Congresswoman Susan Davis (D-San Diego). Other local leaders, including representatives from the Peninsula Community Planning Board, Point Loma Association, Coastkeeper, Audubon Society and Peninsula Chamber of Commerce, were briefed on Tuesday, Aug. 1.
A second phase of wells “” already permitted and extending further into the community “” will be placed the week of Aug. 7, though information from the sites will not be readily available for another two to three weeks. A third phase is planned if necessary. Patton said the process will continue until the plume’s northernmost boundary is established.
“We need to see where it’s gone,” Walsh said. She stressed that identifying the plume’s perimeter is currently the most pressing step and one that must take place before a corrective action plan can be developed.
Such a plan was slated for completion in September, though incorporating the most recent data will push the deadline into October, Walsh said.
The recent announcement is the latest in a series of discoveries about the plume’s boundaries and its curious migration northward and uphill, when for years Navy attention had been focused on halting its downhill and eastern movement toward the bay.
In July, a geologic survey at the base attributed the migration toward the property line to hydraulic forces pushing north as the underground water table flattens as well as small ground fractures detected by electric and seismic signals that might have guided the fuel in that direction.
Now that it is clear that fuel has reached La Playa, Patton said the same noninvasive technology will be employed in the neighborhood to better understand the area. He added that vapor probes have already been set up near the wells and show no indication of health hazards.
Neither Patton nor Walsh commented on a future cleanup plan for the residential extent of the plume, saying it was too soon to guess what action might be needed. Walsh did note, however, that the Navy is responsible for remediation wherever fuel is found.
For five years, the Navy has collaborated with the state and local governments to extract the fuel and water mixture from the ground on the base.
Each week the Navy removes 45,000 gallons of liquid from the affected area. Roughly 128,000 gallons of actual fuel have been pumped out of the plume to date, along with a much greater amount of water, which is extracted from the mixture and sent into the sewer system. The recovered fuel is later resold and reused.
Extraction takes place from the same wells used for monitoring and investigation purposes, which are no wider than 4 inches but reach depths of up to 60 feet. Patton said the Navy has spent $1.5 million to date on well permitting, digging and maintenance.
Both the Navy and the water board maintain that there are no new leaks, only more precise technology allowing both to accurately map the plume.
Rough estimates have indicated that the mass, which lies within 340 yards of San Diego Bay, could be as large as 1.5 million gallons.
Fuel began dripping from the bottom of one of the aboveground tanks in 1999. The petroleum continued to seep through the dry, rocky ground until it hit the water table 50 feet below, where it spread laterally.
Sensors alerted officials to the first leak in 2000, and the Navy took one tank offline. Two more leaks were subsequently discovered in 2002 and 2003.
The Navy is currently pursuing a project to replace the 27 aboveground and 23 underground tanks with 10 state-of-the-art mega-tanks.
As one of the nation’s Strategic Petroleum Reserves, the submarine base stores roughly 42 million gallons of fuel on site for the Navy, Army, Marine Corps and Air Force.
Patton said that $135 million has already been programmed for the project, $10 million more than initial estimates presented in March.
The first dollars are scheduled to be released in October 2007, and construction could begin in early 2008.
Another town hall forum to discuss the latest developments is tentatively planned for September, at which time more conclusive evidence as to the plume’s perimeter should be available.
“The best thing I can do to quell fears is to continue to talk to any groups that want me to come talk to them,” Patton said.