With the addition of new emissions controls as well as changes in EPA standards and regulations, the closure of ash landfills is becoming a more common occurrence. Garrett & Moore has served as the design and closure certification engineer for a significant number of ash landfill closures projects over the past few years to include both lined and unlined ash landfills containing either Class C and Class F fly ashes and other coal combustion residuals.
While on the surface the closure of ash landfills may appear more straightforward than the closure of more conventional MSW landfills containing compressible and LFG producing municipal solid waste, the closure of an ash landfill has its own unique challenges and design considerations. Final grading of the waste mass and resulting overlying closure cap system can play a huge role in the overall post-closure performance of the landfill. Garrett & Moore has strong experience designing final waste and final cover grades for ash landfills that minimize infiltration (and thereby minimize potential for groundwater impacts) as well as provide effective and low-maintenance stormwater runoff management systems. Whether the landfill primarily contains easily gradable and highly erodible fly ash or hardened pozzolonic fly ash requiring rippers or hydraulic rams to break up the ash, Garrett & Moore has designed Owner friendly operational and closure programs that are protective to the environment, cost effective, exceed regulatory requirements, and minimize long-term post-closure maintenance.
Once the landfill is certified closed, Garrett & Moore has also assisted Owners with post-closure planning for the ash landfill sites to include investigating and closure of landfill appurtenances such as regulated NPDES landfill runoff wastewater ponds. While every state’s regulatory requirements are different, proper closure of the landfill runoff ponds can be just as important as the landfill closure in terms of managing and maintaining long-term environmental compliance while minimizing post-closure maintenance.
Garrett & Moore is proud of our work assisting Owners in all facets of coal ash landfill development, operations, and closure and post-closure care. Our track record in this field of work is unsurpassed in the Carolinas.