AIKEN, S.C. - EM and the Savannah River Site (SRS) management and operations contractor are using new technology to spur cleanup of the site’s legacy coal ash.
EM, Savannah River Nuclear Solutions (SRNS), and subcontractors are incorporating new advanced protective barrier technology into the second phase of the Area D Ash Basin Project to significantly accelerate the schedule and lower costs, saving taxpayers more than $300,000.
Workers will consolidate 335,000 cubic yards of ash, coal fines (particle size usually less than one-sixteenth inch), and contaminated soil into a mound. They will cap the mound with geosynthetic material and a thick earthen cover consisting of fill dirt and grass-covered topsoil as they did in the successful first phase earlier this fall.
“We’re pleased with our progress to date; however, consolidating all the ash into two large mounds is only as good as the method used to protect them," SRNS Project Manager Susan Bell said. “That’s why we’re using the highest quality, most technologically advanced techniques and materials to ensure this is the case at SRS."
The barrier is made of highly durable plastic sheets covered with a unique geotextile material. This material permits rainwater to pass through to the plastic layer where the water runs off within numerous small channels, preventing two feet of soil and sod from sifting through and clogging these drainage channels.
“This new geosynthetic plastic-based system ensures rainwater runs off a mound, eliminating erosion and other potential issues," said Bell. “In addition, the new product can be installed faster and at a lower cost."
Workers will install 1.8 million square feet of the material over an estimated 41 acres.
“The key is layers of protection," added Bell. “Each layer has its own purpose, all working together."
SRS generates power and steam through an environmentally friendly biomass plant, but for decades the site’s electricity came from the coal-fired D Area Powerhouse, resulting in hundreds of thousands of cubic yards of residual ash.
In the first phase, workers consolidated more than 90,000 cubic yards of ash and dirt into an existing SRS ash landfill adjacent to the excavation site, resulting in a highly protected mound of relocated material about 21 acres in size.
By the project’s end, workers will have removed about 90 million gallons of water from the basins, excavated and consolidated over 400,000 cubic yards of ash, and remediated more than 90 acres of federal property, protecting the environment, including nearby Savannah River.
The project resulted from a closure plan developed by EM, SRNS, and state and federal environmental regulatory agencies.
Source: U.S. Dept. of Energy, Office of Environmental Management
