The per-and polyfluoroalkyl substances (PFAS) are a group of chemicals used to make fluoropolymer coatings and products that resist heat, oil, stains, grease, and water. Fluoropolymer coatings can be in a variety of products.
An obscure report by the Navy in 2022 on the Former Marine Corps Air Station Tustin describes high levels of PFAS escaping the base 23 years after its closure in 1999.
The Final Preliminary Assessment/Site Inspection Report on Per- and Polyfluoroalkyl Substances, Former Marine Corps Air Station Tustin, describes the migration of the carcinogens and various pathways to human exposure. The report provides a kind of PFAS roadmap to human ingestion.
Frightening concentrations of PFAS in groundwater and surface water are draining from the area of the old base and creating a public health crisis that few are willing to acknowledge. PFAS levels were reported at 836,600 parts for trillion (ppt) for three compounds tested in the groundwater: PFOA (743,000), PFOS (26,900) ppt, and PFBS (66,700). The EPA says it will set enforceable drinking water limits at 4 ppt for PFOS and PFOA by the end of this year. Commercial labs can test for 55 compounds so there is a lot the U.S. Navy isn’t telling us.
Surface water that drains from the old base into San Diego Creek was reported at 199 ppt for PFOS alone. Although the number seems small compared to the groundwater levels, this is concerning because the compound bioaccumulates in living things like invertebrates that fish consume. Bioaccumulation rates for PFOS in aquatic life may be thousands of times greater than the levels in the water.
Groundwater and the regional aquifer flow southwesterly toward the Pacific Ocean.
The Santa Ana – Santa Fe Channel and Barranca Channel carry surface water flow southeast along the edges of the base’s old boundary. The Santa Ana-Santa Fe Channel discharges into Peters Canyon Channel which merges with San Diego Creek about a third of a mile southwest of the station. Barranca Channel also discharges into San Diego Creek approximately 1 mile southwest of the old base.
San Diego Creek empties into upper Newport Bay approximately 4 miles southwest of the Station.