Upgrade work at CTP progressing
Courtesy photo A crane sets a piece of the new filtration equipment at the Central Treatment Plant in Kellogg.
KELLOGG — Work on the Bunker Hill Central Treatment Plant continues to move forward at a steady pace.
Last week, work crews began placing new filter equipment throughout the site with a total of seven filter vessels to be delivered to the site over the coming weeks. These are the first of the treatment system process equipment that will arrive at the site over the coming months.
As of now, roughly 20 percent of the upgrade work on the CTP (itself) has been completed and right around 50 percent of the overall project (including CTP upgrade, soil bentonite cutoff wall, groundwater collection system and sludge impoundment facility) is finished.
Rod Zion, the project director with the Army Corps of Engineers, gave a detailed description of the coming work at the CTP, as well as the surrounding work, including the groundwater collection system and barrier wall being constructed.
“For the Central Treatment Plant upgrade, remaining work in general consists of construction of the filter building and installation of treatment process equipment, construction of the reactor facility, and construction and installation of the new thickener tank,” Zion said. “Work ahead also includes construction of the new effluent pipeline system, construction of the in-water diffuser structure to the South Fork Coeur d’Alene River, and completion of various sludge and filtrate piping systems at the new Sludge Impoundment Area.”
He spoke at length as well concerning the groundwater collection system and barrier wall.
“For the Groundwater Collection System, ongoing work includes installation of 12 extraction wells,” Zion said. “Work ahead for the GWCS includes installation of extraction pumps, construction of groundwater collection header, and construction of the dual forced main groundwater conveyance pipeline system to the CTP. For the Soil Bentonite Cutoff Wall, the remaining work consists of closing in gaps in the wall that were left open to allow continued passage of groundwater during construction, as well as some gaps that were left open for some sewer line crossings. The remaining work at the SBCW will be completed after the GWCS is fully operational.”
The work is part of a required remedial action under the U.S. Environmental Protection Agency’s larger efforts to clean up toxic contamination in the basin.
AMEC Foster Wheeler Environmental & Infrastructure Inc., of Blue Bell, Pa., was awarded a $48,140,266 design-build contract in 2016 with the purpose of upgrading and expanding the currently operating CTP and support facilities.
Construction is scheduled to be completed and commissioned by May 2020, but according to Zion, the project is behind schedule.
“As of right now, the project is slightly behind schedule. Schedule slippage is in part due to some adverse weather impacts experienced during the winter,” Zion said. “The contractor is also looking into ways to create more concurrency of activities in their construction schedule to recover schedule slippage.”
Final project completion is currently scheduled for mid-May 2021.