Why this matters:
The Las Flores basin at Camp Pendleton is one of four aquifers that supply drinking water to over 38,000 active service members at the base. It also meets the Pacific Ocean and is a habitat to wildlife.
The U.S. Marine Corps has closed a landfill at Camp Pendleton indefinitely pending repairs in response to a cease and desist order from water regulators, who cited years of environmental violations and contamination.
Since early 2000, the Las Pulgas Landfill has faced multiple hurdles and violations while attempting to expand the facility, the most crucial being the discovery of tears in the liners which prevent toxic fluids in the trash from seeping into the earth.
But the event that proved to be the turning point was when the Marines pumped millions of gallons of a toxic substance known as leachate into the stormwater system during tropical storm Hilary, which subsequently flows into Las Flores Creek and out into the Pacific Ocean. Leachate is the polluted waste water from trash and is known to contain heavy metals such as lead and mercury and other toxins such as benzene and ammonium that are harmful to humans and marine life.
Initial investigations, mandated by the San Diego Regional Water Quality Control Board, took over a year to carry out, which according to Chair Celeste Cantú is too long.
“We often end up at this point, at this ‘kumbaya’ point where everybody sees the light,” Chair Celeste Cantú said at the water board’s February meeting, acknowledging that the Marine Corps has been cooperating.
“The sad reality is the water board does not have the resources or the time to go through that process. And I’m sure the Marine Corps does not either.”
Commander Steve Ramsey, the public works officer at the base, said that costs have “not been insignificant.” He said that the Marines installed a temporary liner over the landfill that cost $4 million, almost as much as the original liner. Trash has since been diverted to the San Onofre landfill, a municipal facility they also own and run.
The water board’s enforcement order demands that Marines cease taking in new loads of waste until the system can face “100 year storm events” without discharging polluted water into storm drains. During the pause, they will also have to repair the torn liner, finish construction and pass a water board inspection.
“We’ve documented years of noncompliance to the notices of violation which demonstrate the Marine Corps’ inability to manage the landfill without board input,” said Frank Melbourn, a water resource engineer speaking on behalf of the board.
The cease and desist order for the landfill is not the first time Camp Pendleton has faced water related violations. Its own water system was found to be in violation of the Safe Drinking Water Act in 2017. The EPA found animal carcasses in treated water at the base and pressured the Marines to address the maintenance of their water systems.
The EPA has also designated Camp Pendleton as a superfund site, meaning that the groundwater has been contaminated as a result of military operations over dozens of years. The EPA found the water to have high levels of chemicals that stem from degreasing solvent and oil dispersant that have been correlated with numerous types of cancer. The Marines have been carrying out remediation since the 80’s, though as of 2019, when the last five-year review took place, the area continues to require more interventions.
At the landfill, some of the contamination has been tied to the leak of leachate from the broken liner. A landfill liner is basically a thick plastic sheet laid over a layer of clay that is meant to stop contaminated liquid from seeping into groundwater.
The story of tears to the Las Pulgas liners drags over two decades.
The first tears were discovered in 2003 on the original part of the landfill, known as Phase 1, soon after new requirements were prescribed for landfills. At that time the Marines voluntarily halted operations, and while investigating found additional damage to the liner.
What followed were years of back and forth between the water board and the Marines, with the water board saying in 2007 the landfill should either close Phase 1 all together, or rebuild it. The decision was to rebuild, and to also finish construction on the new section, Phase 2.
After Phase 2 was completed, Phase 1 was fixed and soon collapsed and tore again in 2017 due to shallow groundwater the builders failed to identify during construction. And while repairing that liner, the liner under Phase 2 was damaged in 2022.
Leachate is normally collected and pumped into a wastewater facility where it is treated. In the case of Las Pulgas, not only was it leaking from the liner, but the design was not capable of sustaining a weather event such as that of tropical storm Hilary which hit in early 2023.
Melbourn said the ground became saturated with water and landfill operators pumped leachate out into surface waters, and the landfill also sustained significant flooding and erosion.
Ramsey said the event and subsequent interactions with the water board have triggered a “conceptual shift” with how they are viewing landfill maintenance.
“We collectively and I personally did not fully recognize the seriousness (of) what was about to happen,” Ramsey said, recounting the impact of the storm.
Ramsey also cited a lack of preparedness due to a contractor not being able to procure the needed top soil to secure the landfill for the winter season.
Lt. Taylor Dorsey said in a statement to inewsource, that the Marines support the cease and desist order and “are working diligently through the process required by the San Diego Regional Water Quality Control Board and remain committed to maintaining the highest environmental standards at Marine Corps Base Camp Pendleton.”
Despite the violations and the cease and desist order, both the water board’s prosecution and the U.S. Marines’ representatives applauded one another for their cooperation.
“It looks like we’re going to have a performing landfill, which is really important,” Cantú said. “We’ve got to do better moving forward.”
