Case Study

Spill Characterisation & Remediation (US)

SLR prepared work plans and completed fieldwork associated with a limited source removal of diesel-impacted soil at a pump station in Alaska. The removal occurred in an area of continuous permafrost and required field screening of the soil and confirmation sampling of the excavation to document attainment of ADEC soil target cleanup levels. Contaminated soil remaining under an active fueling island is being remediated using soil vapor extraction (SVE). SLR installed two SVE wells near the fueling island during this same field effort and the limited removal.

Location:

Alaska

Client:

Confidential Upstream/Midstream Client

Sector:

Oil & Gas

Project Objectives:

SLR provided a full range of remediation activities including monitoring, feasibility studies and remedial design.

Our Role

SLR undertook the following works:

  • SLR designed an SVE system to address gasoline–contaminated soil in place below an active fuel island. The SVE was designed based on the results of a pilot study that measured the air permeability of the soil and the effective radius of the SVE wells. Once the SVE system was completed, SLR began operation during the following summer season
  • SLR also provided a detailed operation and maintenance (O&M) manual for the system to the client. SLR conducts routine operation and maintenance checks of the site, and collects air samples for laboratory analysis of hydrocarbon content. To date, the SVE system has removed petroleum hydrocarbons from the subsurface and has operated without mechanical failure
  •  Surface water and groundwater downgradient of the excavation area and the fuel island are being sampled to monitor the effectiveness of the remedial actions, and this monitoring indicates hydrocarbon concentrations are stable or decreasing.