As the Environmental Protection Agency (EPA) prepares to release its drinking water regulations on perfluoroalkyl and polyfluoroalkyl substances (PFAS), also known as “forever chemicals,” the Tampa Water Department is exploring a pioneering approach that will put it ahead of the curve.

Suspended Ion Exchange (SIX) will help address Tampa’s water quality needs as well as position the Water Department to meet the EPA’s future drinking water regulations. The Tampa Water Department is working to adopt this state-of-the-art technology at the David L. Tippin Water Treatment Facility. Once complete, this SIX facility will become the first in America and the largest in the world.

This technology will push the department to the forefront of the effort to address PFAS concerns. PFASs are manufactured chemicals that are widely used and break down slowly over time. Researchers are trying to determine the impact of long-term PFAS exposure; however, scientific studies show that PFAS may be linked to negative health effects in humans. At press time, the EPA was expected to release its finalized regulations on six PFAS chemicals by the start of 2024. The proposed limits, which have yet to become official, are 4 parts per trillion. To put that into perspective, one part per trillion is equal to a drop of water in 20 Olympic-sized swimming pools.

The Tippin Water Treatment Facility monitors PFAS levels in its finished water as required by the EPA’s Unregulated Contaminant Monitoring Rule. Testing completed over the last year showed some PFAS variants were detected in the samples, with the levels of two PFAS chemicals, PFOA and PFOS, detected slightly above the proposed limits in some samples. More than 33% of Florida’s water treatment facilities exceed the proposed limits.

Only a limited number of technologies can minimize PFAS levels in drinking water. While many utilities are still trying to determine how to address the upcoming regulations, the Tampa Water Department already has a framework in development, and SIX is an essential piece of that solution.

“The City of Tampa and the Tampa Water Department are committed to providing our residents with clean, safe drinking water,” said Mayor Jane Castor. “There are a limited number of technologies capable of minimizing PFAS levels in drinking water, making this technology a critical investment to improve the quality of our water for generations to come.”

The Tampa Water Department initially piloted this technology in 2020. The pilot program showed that SIX will provide added benefits, including:

• Reducing the amount of chemicals needed to treat the drinking water, which will save the department approximately $1.4 million each year
• Improving the quality of the drinking water
• Increasing operational safety at the Tippin Water Treatment Plant.

The results of the pilot were so promising that the SIX pilot is being tested at the Howard F. Curren Advanced Wastewater Treatment Plant. The technology is of interest to many other utilities in Florida and beyond, and seven utility tours were scheduled in November and December.