Southern California Gas Company
Former Aliso MGP Site, Los Angeles
Shoring
Shoring of an active MTA maintenance building during the remediation by a non-vibratory method using bucket auger drilling and cement Slurry piles to facilitate the removal of impacted soil to ground water level 30 ft deep. (Photo shows the backfilling of the saturated zone with pea gravel)
Vapor Barrier
Installation of a multi-layer plastic vapor barrier along the a boundary of the excavation not accessible to cleanup at this stage
Odor, VOC, and Hydrogen Sulfide Control
Odor, VOC, and hydrogen sulfide control during subsurface excavation by in-situ vapor extraction and an emission control system consisting of a combined low temperature scrubber for hydrogen sulfide followed by high temperature thermal oxidizers for aromatic VOCs and methane.
Odor, VOC, and Hydrogen Sulfide Control
Reaching the impacted ground water approx. 30 ft bgs and excavating the impacted saturated soil (the ground water zone was treated with Oxygen Release Compounds and backfilled with gravel)
Odor, VOC, and Hydrogen Sulfide Control
The contaminated groundwater at a depth of around 30 feet below ground surface was accessed, and the contaminated soil in the saturated zone was removed by excavation. Oxygen Release Compounds were applied to treat the affected groundwater, and the area was refilled with gravel.
Dust Control
Dust control utilizing both high pressure spray and fire hose during the excavation of the impacted soil.
