Project: Terminal 117
CERCLA Removal Action & EE/CA
Terminal 117 Early Action Area
Terminal 117 is the site of a former asphalt roofing materials manufacturing facility that operated between 1937 and 1993. PCBs, TPH, dioxins, and PAHs have been detected at elevated levels at the site and triggered EPA to designate the site as an Early Action Area of the Lower Duwamish Superfund site. CRETE was part of the team that developed the EE/CA that was completed in 2011.
CRETE is now leading a multi-disciplinary team that is preparing the design and bid documents for the sediment and upland removal action. The cleanup is anticipated to include the dredging of about 10,000 cubic yards of sediment and the excavation of about 35,000 cubic yards of soil. The team identified key design issues, project risks, and construction cost drivers early in the design process and is now working with the Port and other agencies to provide a design that incorporates regulatory, engineering, and bid strategies to address these items. The design will be completed in 2012. The cleanup is anticipated to be performed between Summer 2013 and early 2014.
CRETE principals previously managed a Time-Critical Removal Action to remove and dispose of PCB-contaminated soil, including: regulatory negotiations, preparation of relevant work plans (SAP, QAPP, CQAP, CMP, FSP), public involvement support with the local neighborhood association and other stakeholders, and preparation of the construction scope of work and construction oversight.
CRETE principals also managed a temporary bank repair due to slope failure. A keyed riprap design was used to minimize habitat disturbance, avoid disturbance of substrate soils, provide a design life that extends beyond the time horizon for site cleanup, and minimize the amount of fill material.
Work Performed
- Regulatory negotiations - CERCLA/MTCA
- Permitting - TSCA risk-based disposal approval, EPA off-site policy rule, biological assessment
- Sediment and upland cleanup design
- Construction oversight
- Upland and sediment EE/CA
- Insurance cost recovery
- Groundwater-surface water fate and transport
- Dioxin forensics
Value Added
- Implemented a removal action in a residential area with intensive stakeholder involvement
- Designed, permitted and implemented a temporary bank repair
- Obtained a non-potability determination for site groundwater
- Negotiated cleanup levels incorporating groundwater-surface water attenuation due to tidal influence
- Participated in a dioxin forensics work group that concluded that the site was likely not a significant contributor of dioxins to the neighborhood