Client: Alaska Army National Guard
Location: Emmonak, Fort Yukon, and Kotlik, Alaska
Completion Year: 2017
Scope of Work:
- Remedial investigation (sampling and analysis; drilling; groundwater monitoring)
- Removal actions (soil excavation; confirmation sampling, ground and surface water monitoring)
Brice executed environmental services at three Federal Scout Armories located in western Alaska. All three sites are accessible only by air and sea. To execute the project, we prepared site-specific work plans including UFP-QAPP to establish DQOs; a Sampling Analysis Plan; Project Management Plan and project schedule; and Community Relations, Waste Management, Contractor Quality Control, and Site Safety and Health Plans.
At Emmonak, Brice performed a remedial investigation (RI). Petroleum contamination was present from potential sources including leaks or spill from drums, tanks, or pipelines; releases at the adjacent Lower Yukon School District Tank Farm; and a fuel line break from the heating oil tank on the City property. We used a Geoprobe 6610 DT direct push drill rig to UVOST probes and soil borings to facilitate field screening and analytical sample collection. Four monitoring wells were installed and were sampled for DRO, RRO, GRO, BTEX, and PAH. Brice recommended that a removal action be performed. We further recommended that if ADEC determined that petroleum contamination detected in groundwater poses unacceptable risk, that groundwater transducers be installed in the four monitoring wells to monitor groundwater elevation and retrieve data quarterly for one year to measure seasonal fluctuations.
At Fort Yukon, Brice removed 16 cubic yards of petroleum-contaminated soil to achieve a No Further Action (NFA)/Cleanup Complete Determination with no institutional controls (ICs). Soil with contaminant concentrations exceeding the ADEC-approved cleanup levels identified in the ROD was removed and replaced with clean backfill. We also removed soil contaminated with DRO, 1-methylnaphthalene, and 2-methylnaphthalene to facilitate a Cleanup Complete determination without ICs. Excavated material was loaded into 16 Super Sacks, one-cubic yard in size. When the Yukon River thawed in May 2017, the Super Sacks were transported via barge to Nenana, then trucked to Alaska Soil Recycling in Anchorage for treatment and disposal.
At Kotlik, we excavated 34 cubic yards of petroleum-contaminated soil to achieve the ADEC-approved site-specific cleanup levels; collected field screening and confirmation soil samples; and backfilled and restored the site. We then began long-term monitoring of groundwater and surface water, installing four monitoring wells. Samples are collected annually for five years.