Coal Ash Ponds and Landfill Closure  

TRC’s engineering and construction services during closure helped the project proceed without significant interruption. 

Coal Ash Ponds and Landfill Closure   

The client operated coal-fired boilers at their facility for many years and managed the staging and disposal of coal combustion residuals (CCR) in ponds. These coal-fired units have been retired and the CCR ponds are no longer required. The client also had an on-site landfill. This 3-year project involved closure of the multiple CCR ponds, with final disposition of the CCR in the on-site 12.5-acre landfill, and final closure of the landfill. The CCR ponds encompassed 12 acres and were 18 feet deep. The site also had former process water ponds (previously closed) that were part of the final site restoration activities that encompassed 6.5 acres and were 10 feet deep. TRC served as the project’s remediation contractor. 

TRC’s construction team self-performed the excavation of approximately 165,000 cubic yards of CCR from the three existing CCR ponds. Prior to removal, the CCR ponds were dewatered. Once dewatered, the CCR was excavated, stabilized, transported, and placed into the on-site landfill. This included addressing significant water management challenges due to severe weather during closure operations. 

Following the CCR removal activities, TRC completed the landfill closure which included review of the final cover system design for constructability, establishment of erosion controls, re-grading of the existing side slopes, installation of storm water drainage features, and installation of the final lined cover system, which had been previously approved by the state agency. 

Site restoration activities included re-grading five former process water ponds and the three closed CCR ponds to optimize long-term storm water management at the site within construction budgets. Additionally, a new wildlife habitat and wildlife habitat credit was created within the former CCR ponds. 

TRC provided both engineering and construction services during the closure activities, allowing the project to proceed without significant interruption. Closing the CCR pond system, capping the landfill, and restoring the site completed the regulatory closure at the site and significantly reduced the long-term liabilities for the site owner, without disrupting site operations. 

Client

Confidential Client

Project Location

US