The CFPUA Board on Wednesday, August 10, received an updated project schedule for new granular activated carbon (GAC) filters at the Sweeney Water Treatment Plant.
The GAC filters have been under construction since November 2019 and are being built to provide effective treatment for Chemours’ PFAS contamination such as GenX.
On Wednesday, a representative from Black & Veatch, the contracted project manager for the filter project, outlined the latest schedule. Under the new schedule, all eight of the new Granular Activated Carbon (GAC) filters are projected to be available for service in late December 2022.
However, based on projected drinking water demands, only four of the eight filters need to be online to provide effective PFAS treatment – to a standard where, for example, levels of GenX are at or near non-detection. Under the schedule announced Wednesday, that should occur prior to December. If work goes as currently planned, CFPUA customers in the Sweeney water system could begin receiving drinking water effectively treated for Chemours’ PFAS by early fall 2022.
Much of the preparation and testing for one filter must be completed before work begins to prepare and test the next filter. As of Wednesday, August 10, preparation and testing had been completed on one filter and was in process for a second one.
CFPUA will provide regular updates online and on its Facebook, Instagram, and Twitter accounts as work continues to bring the filters online.
In late July, trucks carrying GAC media for the new filters began arriving at Sweeney. Trucks with GAC for the filters arrive outside the facility, where Adams Robinson and subcontractor Calgon Carbon begin the loading process. Each filter will hold 320,000 pounds of GAC – eight truckloads delivered over about three days.
Once GAC is installed in a filter, it must be “washed” and “rinsed” over a number of days to prepare the GAC media and achieve water-quality parameter goals such as proper pH. This process will occur in succession for each of the eight filters.
According to Black & Veatch, the Sweeney Treatment Enhancement Project is facing delays resulting from a number of factors, including supply-chain and labor-shortage challenges similar to those affecting projects throughout the region.
The new filters are being constructed and made operational while Sweeney, already among the state’s most sophisticated water treatment plants, continues to produce about 80 percent of the drinking water CFPUA distributes to its customers.
Picture from August 3, 2022, shows water in one of eight new GAC filters at Sweeney during the “washing” process.