ETIC implemented the corrective action plan for a major utility company that included excavation of petroleum hydrocarbon-impacted soil, dewatering activities, transportation and disposal of impacted soil and groundwater, backfill and compaction of the excavation using clean imported material, and site restoration activities.
Prior to initiation of field activities, ETIC prepared a site-specific health and safety plan and an Environmental Controls Plan that included spill prevention, controls, and counter measures to be implemented as well as storm water pollution prevention and dust controls measures. The excavation area was then cleared and the existing asphalt was saw-cut and removed.
The sheet-pile shoring system was installed per the project-specific Excavation Support and Protection Plan. The soil within the interior of the shoring was excavated to a total depth of 27 feet below ground surface (bgs) using a combination of excavators to excavate between 10 and 15 feet bgs, followed by use of a mini-excavator, which was lowered within the excavation using a crane, to reach the total depth. The excavated areas were then backfilled and compacted. All excavated soil was transported offsite by a preapproved transporter at a preapproved facility. Dust suppression measures were accomplished by using a trailer-mounted water tank and pump during soil excavation, stockpiling, and truck loading activities.
Following completion of the excavation backfilling activities, the sheet-pile shoring was removed, and the asphalt pavement was replaced to match the existing surface using hot-mix. Lastly, final site clean-up was performed, and all equipment was removed from the site. A final survey of the adjacent structures was conducted by a licensed surveyor to check for settlement.
Client: Major Utility Client
Location: Grass Valley, California
Duration of Project: Aug 2009 – Nov 2009