Assessment and Remediation at Bulk Storage Site

The challenge:

Petroleum-impacted groundwater from a bulk petroleum storage facility was discovered discharging from a groundwater spring to a stream commonly used for recreational fishing. GES was contracted to investigate the source of petroleum impact to the spring, identify and implement a corrective action strategy, and evaluate the possibility of retrofitting a previously-existing sparge system to effectively address the source material discharging at the spring.

The GES solution:

GES conducted a geophysical survey, geologic mapping, fracture trace analysis, and a literature review to identify features and possible transport mechanisms for the migration of petroleum-impacted groundwater to the spring. An additional microgravity geophysical survey identified a fracture trend oriented directly towards the spring discharge location. Extensive soil boring and monitoring well installation activities aided in defining the source of contamination and migration pathway to the spring. GES selected a soil vapor extraction system as the most appropriate technology and prepared a detailed engineering design package including the use of a catalytic oxidizer to treat recovered soil vapors.

The benefits:

The geophysical survey allowed for effective well placement, thereby reducing overall drilling, sampling, and monitoring costs. Through adequate source delineation, soil vapor extraction wells were installed in the pipe manifold area without compromising the integrity of underground utilities. Improved groundwater quality at the spring discharge point was observed within six months of continuous active soil vapor recovery efforts in the pipe manifold area.