Design-Implement, NAPL Treatment Pilot Study

Design-Implement, NAPL Treatment Pilot Study, IR Site 03 – Former Oily Waste Ponds, Parcel E, Hunters Point Naval Shipyard, San Francisco, CA

Designed and performed a pilot test to test a) in-situ thermal remediation (ISTR) using thermal conductive heating (TCH) to aggressively remove mobile non-aqueous phase liquid (NAPL) oily waste to protect San Francisco Bay, and b) in-situ solidification/stabilization to reduce NAPL migration to nearby ecological receptors in the San Francisco Bay.  The phases of work consisted of design, field implementation, data evaluation, reporting and recommendations.

  • Prepared planning documents, including a Work Plan, SAP/QAPP/FSP, Health & Safety Plan, Waste Management Plan, Environmental Protection Plan, QC Plan, and Radiological Material Management Plan
  • Pre-design characterization included tidal influence study and pump test (24-hour constant rate test, using 16 transducers) to facilitate remedial design
  • Soil and groundwater characterization, including 60+ soil and 13 baseline groundwater samples
  • In-situ Thermal Remediation (ISTR) using Thermal Conduction Heating (THC) Pilot Test
    • Designed remediation system for 46 heater wells, 46 co-located vacuum extraction wells, 14 MPE wells, 7 re-injection wells, 10 temperature and pressure monitoring points, and off-gas vapor treatment system including manifold piping network, vapor liquid separator/knock out tank, air heat exchanger, blower, and GAC
    • Installed an used 46 TCH heater wells to generate heat to produce steam agitation/ stripping and to reduce NAPL viscosity
    • Performed NAPL extraction from 14 MPE wells
    • Horizontal vacuum extraction wells at ground surface provided pneumatic control of upper zone during subsurface heating
    • Re-injected treated warm water into 7 wells to retain heat optimization system and provide hydraulic control
    • Design included two heat exchange units which allowed formation temperatures to reach 100 degrees C within the two weeks of start-up
  • Sampling and analyses to assess effectiveness
  • In-Situ Solidification/Stabilization (ISS) Pilot Test
  • Coordinated with USEPA Region 9, state EPA (DTSC and RWQCB-SF), and San Francisco Redevelopment Agency

Contract Value $3.7 Million