Effort launched to reassess sediment contamination at Palos Verdes Superfund site

SCCWRP has launched a follow-up study examining the state of sediment contamination along the Palos Verdes shelf a decade after completing the Superfund site’s last ecological condition assessment in 2012.

The 13-month study, launched in September, involves deploying passive samplers to measure levels of the pesticide DDT and an industrial class of chemicals known as PCBs that are leaching out of surface layers of sediment into the water column above.

Although DDT and PCBs were banned decades ago, millions of pounds of these chemicals were discharged to the 17-square-mile Superfund site in the years prior. The chemicals can continue to exert toxic effects for decades.

Passive sampling devices measure the portion of contamination in seafloor sediment that dissipate into the water column over time, creating potential exposure routes for sediment-dwelling marine life. SCCWRP is using the same passive sampling-based study design that was used during the site’s 2012 sediment quality assessment.