Paper_CAPPING & CLOSURE FOR TWO PENNSYLVANIA LANDFILLS SUBJECT TO U.S. EPA’S CCR RULE PROMULGATED UNDER 40 CFR 257 SUBPART D

Paper_CAPPING & CLOSURE FOR TWO PENNSYLVANIA LANDFILLS SUBJECT TO U.S. EPA’S CCR RULE PROMULGATED UNDER 40 CFR 257 SUBPART D

Grand Rapids, Michigan

This project consisted of capping two coal combustion residuals (CCR) landfills with geosynthetic capping systems consisting of 24-inches of final cover soil over eight ounce per square yard filter/separation geotextile over Super Gripnet geomembrane with drainage studs along top and friction spikes along the bottom over a prepared subgrade consisting of in-place cover soil. Approximately 20 acres were capped at each landfill in 2023. Closure plans addressing CCR Rule requirements were prepared and posted to the stations’ CCR Rule websites. Per those plans, the stations intend to cease coal combustion and residual waste disposal by year-end 2028. To comply with Title 25, Pennsylvania Code §288.234(d), requiring closure within one year after cessation of waste placement, approximately 30 acres of each 200-acre site must be capped yearly between 2023 and 2029. This presentation will review the cap system alternatives investigated, cap system selection per site conditions, cap system design, permitting, pre-construction test pads for rock sizes above and below cap system geosynthetics, construction issues and mitigation solutions, stormwater control during construction, and termination details along both the toe of the landfill and adjacent future capping phases as well as permit revisions to reduce cover soil thickness along benches and slopes.