Major Oil Company

Lansdowne, Pennsylvania

Roux Associates performed all investigative and reporting requirements for the Pennsylvania Department of Environmental Protection (PADEP) which ultimately led to the design, construction, and operations and maintenance (O&M) of a 20 gpm combined groundwater depression/250 standard cubic feet per minute soil vapor extraction (SVE) system capable of treating unsaturated soils, light non-aqueous phase liquid (LNAPL), and residually-impacted groundwater. During preparation of the design package, Roux Associates prepared technical specifications and detailed design drawings for the civil, mechanical, electrical, and control components of the project. The design package included necessary information for local building permits and planning board approvals. Upon completion of the detailed design, Roux Associates conducted the project for our client as a design construct with construction management and O&M.

The treatment system consisted of five pneumatically-operated extraction pumps used to depress groundwater and recover separate-phase product in the vicinity of the released petroleum source area. Each well was retrofitted for SVE. Both the combined fluids and vapor streams were conveyed to the treatment compound whereby moisture was removed from the air stream prior to treatment via thermal/catalytic oxidation. LNAPL and groundwater were treated via oil/water separation, bag filtration, and carbon treatment prior to discharge to the local publicly-owned treatment works. Initial concentrations in the vapor stream exceeded 73,000 parts per million (ppm) of total petroleum hydrocarbons (TPH) and within six months of startup, TPH concentrations were non-detected after conducted cyclical and pulsed SVE operations.

Groundwater concentrations dropped from separate-phase product to below PADEP ACT II groundwater quality criteria within 10 months of operations. PADEP approved the cessation of both the SVE component and the groundwater component.