Black & Veatch, the firm CFPUA has contracted to design and manage the ongoing pilot test at Sweeney Water Treatment Plant, has provided its project update for the month of December 2017. The update details the most recent results from the Granular Activated Carbon (GAC) and Ion Exchange (IX) technologies, in addition to outlining the plan for integrating new types of media into the project in mid-January 2018.
As can be seen in the report, both of the established GAC and IX test columns have seen total breakthrough of GenX and other short-chain per-fluorinated compounds. New types of GAC and IX media will now be installed to measure and compare their effectiveness in removing those compounds.
Aside from measuring the breakthrough rates of compounds, the pilot test also collects data on the adsorption properties of the media. As has been reported previously, both GAC and IX media undergo a process known as chromatographic peaking—the preferential adsorption of one molecule over another. As the media fill with compounds they have treated out of the water, they can begin to release older compounds back into the water. Monitoring this process during the pilot test will allow CFPUA staff to feed those factors into the decision process when selecting potential treatment technologies.
CFPUA will continue to share monthly updates on the pilot test with the public as the project progresses. For the most recent results of the pilot test sampling, see our Special Compound Testing webpage.
We have received the results for December 28 from our on-going GenX testing at the Sweeney Water Treatment Plant. Levels of GenX continue to remain below the DHHS health goal of 140 parts per trillion (ppt).