Per- and Polyfluorinated Substances (PFAS)

CATEGORY OF SERVICE, LOCATION:

PFAS Investigation Work Plan  and Site Characterization, Mountain View, California

TYPE OF CLIENT:

Valley Oil Company, Oil Services Distributor

BACKGROUND:

  • The owner (“discharger”) of bulk fuel terminal received a directive from the California State Water Quality Control Board (SWRCB) requiring the owner to screen property for Aqueous Film Forming Foams (AFFF) which may have contained per-polyfluoroalkyl substances (PFAS)  as fire-fighting agents in the foam.

  • Failure to comply would result in financial penalties up to $25,000 per day.

  • Regulatory compliance required the submission of a PFAS Investigation Work Plan, including a review of historic facility operations with regard to fire-fighting measures, and general chemical handling and operational practices.

PFAS Investigation

CLIENT GOALS FOR PROJECT:

Client requested Trinity to assist with the timely submission of the Work Plan, Performance of the Investigation and preparation of the Report of Findings.   

PROJECT APPROACH:

  • Trinity developed a scope of work, an analytical and sampling program, and QA/QC measures related to PFAS investigations. Trinity followed Santa Clara County guidance for the work plan preparation.

  • The analytical program involved testing near surface soil, surface water run-off collected in sewers, stormwater, and groundwater. 

RESULTS, RESOLUTION, NEXT STEPS:

  • The investigation results showed PFAS chemicals in all samples at varying concentrations; however; QA/QC samples (field blank samples) contained highest detections of PFAS chemicals, which raised suspicion to source of PFAS-chemicals detected in samples

  • Trinity initiated quality control testing of laboratory supplied de-ionized water, decontamination water brought on Site by drillers, and local municipal supply obtained from the onSite faucet. Test results revealed that the de-ionized water (confirmed by spilt samples to two different labs) and Santa Cruz municipal supply water brought onSite by the driller contained PFAS chemicals; Santa Clara local municipal supply water was PFAS free. 

  • Tested absorbent product used to contain fueling spills, and found adsorbent contained multiple PFAS compounds. The adsorbent comes in to contact with surface water run-off to explain detections in surface water samples.

  • Trinity demonstrated to regulators that samples results were affected by decontamination procedures.

  • Site was issued a no further action letter with regard to PFAS issues.