Fly Ash Ponds and Bottom Ash Pond Closure
Location: Hutsonville, Illinois
Per Illinois Pollution Control Board rulemaking, Ameren developed procedures for ash pond closure at their Hutsonville, Illinois Power Station. These procedures outlined the final cover system, as well as a Construction Quality Assurance (CQA) Program.
The Ameren Hutsonville Power Plant has been decommissioned. In a previous project, the unlined Ash Pond D was capped in place and a groundwater collection system was installed to address environmental impacts. Four additional ash ponds remained on site, including the unlined Bottom Ash Pond and the lined Ash Pond A, Ash Pond B, and Ash Pond C. The ash in the Bottom Ash Pond, Ash Pond B, and Ash Pond C was relocated to Ash Pond A and they were clean closed with storm water controls. Ash Pond A was capped using a traditional RCRA Subtitle D cap of 40-mil HDPE liner with a 3-foot vegetative cover.
Geotechnology implemented the CQA which included QA/QC for clean closure of three ash ponds and a cap closure of one ash pond which included base subgrade, geosynthetic liner, vegetative cover, and storm water controls. Soils testing was performed by Geotechnology’s geotechnical soil laboratories. The CQA plan also included CQA monitoring, inspection and sampling/testing to verify compliance with project plans and specifications. It also required preparation of an acceptance report at the end of construction that provided all inspection and testing documentation and certifies that the facility has been constructed in accordance with the engineering design.
Weekly reports were prepared for the owners review that included construction activities/progress, equipment and personnel on-site, and copies of daily field observation reports.
Geotechnology’s ash pond closure experience provided real-time solutions to issues that developed during this large scale project.
The successful completion of this project represents one of the first regulated and engineered ash pond closures in Illinois. The project will be an important model for future ash pond closures.
For further information regarding ash pond closure and regulations, click here.