Prima Deshecha: Questions We Believe Should Be Resolved Before Local Landfill Expansion
Ladera Health Watch is now working with residents and advocates concerned about the proposed increase in operations at Prima Deshecha Landfill.
Orange County is considering increasing the landfill’s permitted daily tonnage from 4,000 to 8,000 tons per day, with up to 10,000 tons on certain emergency days. The County’s environmental review is still underway, and its website currently says it is reevaluating the proposed Final Subsequent Environmental Impact Report.
As we have reviewed that record, one thing has stood out: some of the most significant concerns are already in the regulators’ own files.
In March, South Coast AQMD reviewed the County’s Draft SEIR and underlying modeling and raised concerns about the use of older meteorological data, omission of landfill flares and other stationary sources from the health-risk analysis, the need to better evaluate actual residences and schools, and the lack of analysis showing how the proposed increase would affect landfill-gas generation and control capacity. AQMD said excluding certain stationary sources likely underestimated potential cancer and non-cancer risks to nearby sensitive receptors.
We are also looking closely at the landfill’s historic unlined disposal areas and historical industrial waste. Water Board records identify WMU2 as a closed, pre-regulation landfill that accepted waste from 1973 to 1980 and still has an approximately 26.42-acre unlined waste footprint that future Zone 4 development would incorporate.
One historical record is particularly relevant. Orange County records show that in January 1991 approximately 3,350 tons of hydrocarbon-contaminated soil associated with TRW were disposed at Prima Deshecha after the material was tested for acceptance at a Class III landfill. TRW was later acquired by Northrop Grumman in 2002.
We do not know from the records we currently have where within Prima that material was placed, and its disposal there is not evidence that it is currently causing contamination.
But it raises an important, answerable question: is the existing monitoring program designed to detect the specific contaminants associated with the historical wastes disposed in the landfill’s older areas?
Prima is monitored under current Water Board requirements. The question we are examining is not whether monitoring exists, but whether a regulatory compliance-monitoring program necessarily answers the historical-waste questions now being raised.
Before any increase is approved, we believe the final environmental review should clearly address:
whether existing groundwater, leachate, surface-water and other monitoring is sufficient to evaluate contaminants associated with specific historical waste streams;
where known historical industrial wastes were disposed and what monitoring covers those locations;
how significantly increased waste intake would affect landfill-gas generation and control capacity;
emissions from flares and other stationary sources;
impacts on actual nearby homes, schools and other sensitive receptors, including San Juan Hills High School; and
whether updated air and health-risk modeling reflects current meteorological conditions and surrounding development.
Our position is straightforward: before Orange County substantially increases Prima Deshecha’s permitted daily tonnage, the final environmental review should demonstrate that the concerns raised by regulators, and the questions raised by the landfill’s historical waste record, have been adequately addressed using current data.
Thank you for continuing to support this work. We'll keep sharing developments as they happen.
Thank you to everyone continuing to help move it forward.
Sincerely,
Jackie French Ladera Health Watch
