AMEREN Illinois

Prior to remedial activities, O6 ENV and its subcontractors installed an engineered earth retention system, consisting of drilled tangent pilings to allow for remedial extents adjacent to open public ROWs. The work was performed within the city street and immediately adjacent to the most active fiber-optic service line in Champaign County. Impacted soils were excavated from greater than 25 feet below the ground surface.

Approximately 25,000 tons of impacted soil was excavated with an 80,000 lb. hydraulic excavator and loaded into end dump trailers and transported to Republic Brickyard Landfill for disposal at the Sub-Title D landfill. The impacted soil was manifested as Non-RCRA Regulated Waste under 40 CFR Section 262.34(a) which provides a RCRA Exemption for certain wastes generated form former manufactured gas plant activities. Additionally, 200,000 gallons of MGP-impacted groundwater were treated via an onsite wastewater treatment plant operated by the O6 ENV Class K operator and released to the local POTW.

The excavations were backfilled using soil and gravel from an off-site borrow source. The borrow material was transported by tandem truck, placed with a dozer, and compacted to the specified levels.
An extension site restoration project was performed by O6 ENV and its subcontractors to reconstruct the city streets, storm sewers, and streetlights within the project boundaries.