Savannah River Nuclear Solutions personnel said they saved taxpayers $9 million while consolidating more than 400,000 cubic yards of coal ash and ash contaminated soil excavated from across 90 acres at the Department of Energy’s (DOE) Savannah River Site (SRS).
Crews cleaned up pond-like basins used to manage the coal byproducts from the D-Area Powerhouse, which provided steam and electricity for SRS missions for more than 59 years. SRS shut down the powerhouse in 2012 and began using biofuel facilities which burn forest debris, agricultural waste and scrap lumber.
The mammoth cleanup task at SRS was completed more than a year ahead of schedule. The result is two mounds of coal ash and soil, each having a water-shielding, highly protective cover in place.
“Our goal was to safely and cost-effectively protect the environment locally as well as the nearby Savannah River,” SRNS D Area Project Manager Susan Bell said. “We were pursuing performance excellence and timely completion with this multi-year project, and those goals were not just met, but exceeded.”
Phase one of the cleanup project consolidated over 130,000 cubic yards of ash and impacted soil onto an existing 21-acre ash landfill. Completion of this phase formed the first of two highly protected areas in D Area.
Phase two consolidated almost 300,000 cubic yards of ash, coal fines and contaminated soil from two basins and adjacent wetlands into a second huge and carefully-protected area. Like the landfill, it was fully capped with geosynthetic material and a thick earthen cover consisting of fill dirt and grass-covered topsoil.
The geosynthetic, polyethylene-based system used ensures rainwater runs off the mounds, eliminating erosion and the possible migration of contaminants to the groundwater.
Approximately 1.8 million square feet of geosynthetic material, covering approximately 20 acres, was installed over the second mound.
“The key is layers of protection,” Bell added. “Each layer has its own purpose, all working together.”
The SRS D Area Ash Project is a result of a closure strategy developed and approved by a core team consisting of members of DOE-Savannah River, SRNS and state and federal environmental regulatory agencies.