PROJECTS: ENVIRONMENTAL REMEDIATION
Coal Combustion Residual (CCR)
Pond Closure Solutions
Forgen is a trusted utility partner, successfully managing Coal Combustion Residual (CCR) pond/impoundment closure and Effluent Limitations Guidelines (ELG) requirements. Many civil contractors are skilled at moving soil from “point A to point B”, but are rarely versed in the thixotropic nature of wet CCRs or complex risk mitigation strategies required to handle these projects and their potential environmental impacts. We can provide subject matter experts in CCR chemistry, production, beneficial use, power plant CCR operations, and CCR environmental management requirements, as well as full service offerings for complete management of utility plant CCR and ELG requirements. Services complimentary to this type of work include slurry walls, dredging, dewatering, water management, stabilization, source removal, and repository construction.
ARAPAHOE STATION CCR POND CLOSURE
- Excavation and closure of six coal ash ponds
- 190,000 tons of CCR waste material excavated and removed from site
- 335,000 cy of subgrade cut and fill placement
- Construction of 1,200 lf of surface water controls
- Construction of 360,000 sf of infiltration ponds
The client for this high visibility urban pond closure was a large Colorado utility serving more than 3.3 million electric customers and 1.8 million natural gas customers. Company holdings at the time included thirteen coal fired power plants (seven located in Colorado), three wind farms, 27 hydroelectric plants, and two nuclear power stations. The decommissioning of the plant was driven by EPA’s rulemaking governing the management of Coal Combustion Residuals (CCR) which was promulgated in response to the TVA Kingston Coal Ash spill of 2008. All infrastructure and waste associated with the plant needed to be removed in order to allow the property to be effectively marketed and re-developed in the future.
FLY ASH REMOVAL & TRANSPORTATION
FORMER COAL-FIRED POWER PLANT
- Removal of approximately 7.5 acres of fly ash
- Approximately 6,000 cy or about 120 truckloads moved daily
- Removal of 212,500 cy of fly ash from river bank
- Sensitive residential and business area
The City of Kalamazoo acquired land for development on the northeast edge of Kalamazoo’s downtown area and along the Kalamazoo River which had accumulated fly ash from a former coal-fired power plant once operated by a Michigan-based utility. The ash covered about 7.5 acres of this site and reached to heights of 25 ft in some places. After analyses, the City concluded that the cost of removing the ash was prohibitive, but through a collaborative effort with the Michigan Department of Environmental Quality, a Michigan-based utility company, and two engineering firms, a revised approach made the project affordable by transporting the ash to landfills to be used as fill material to contour the sites for closure. This project required significant coordination to effectively execute the work including a tightly managed, continuous flow of trucks traveling between the ash site and the landfills. Approximately 6,000 cy, or about 120 truckloads, per day was moved while minimizing dust and noise to the surrounding businesses and residential areas.
ENVIRONMENTAL REMEDIATION PROJECTS
INFRASTRUCTURE TECHNOLOGIES PROJECTS