Water treatment Membranes Americas
Wednesday, 23 November 2022

IX protection against PFAS: US District hires specialists to safeguard water supplies

The South Adams County Water and Sanitation District has hired environmental and construction services firm Brown and Caldwell to design a new ion exchange process to protect its water supplies from PFAS. 

Taking the fight to PFAS 

The South Adams County Water and Sanitation District has hired environmental and construction services firm Brown and Caldwell to design a new ion exchange (IX) process to protect its water supplies from Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS). 

Brown and Caldwell will design an 18 million gallons per day (MGD) IX process at its Klein Water Treatment Facility in the State of Colorado. 

Consisting of seven new IX treatment trains, a 375,000-gallon equalisation tank, and six vertical turbine pumps to feed the IX trains from the District’s 13 groundwater supply wells, the Klein Water Treatment Facility is expected to complete construction by the end of 2026. 

In addition, nine 5-micron cartridge filters will be installed as an extra barrier to remove water-borne particulates before reaching the IX trains.

Once finished, the facility will have a combined capacity of 26 MGD.

Currently, the District serves 67,000 residents.

Moving the PFAS goalposts

The move comes as the US Environmental Protection Agency (EPA) lowered its interim lifetime Health Advisory Levels (HALs) for PFAS in drinking water supplies. 

It recently lowered its HALs for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) from 70 parts per trillion (ppt) combined to 0.004 ppt for PFOA and 0.02 ppt for PFOS.

The EPA has moved the goalposts, and we are taking steps to reduce the presence of PFAS even further.

Abel Moreno, district manager, speaking on the lowered HALs, said: “Ever since the district first began voluntarily testing for PFAS, we have been monitoring for these compounds and working to reduce their impact on our customers.

Currently, while the district maintains test levels below 70 ppt for PFOA and PFOS, it says that the new HALs are set so low that it is not yet possible to detect the presence of the compounds at these levels scientifically.

The battle against PFAS has begun

PFAS is being called one of the biggest challenges facing the water sector today. 

Previously in the United States, there was a lack of federal policies to protect US citizens from the negative impact of PFAS. 

Then in July 2021, Congress passed a bill that would see the EPA enact limits on PFAS chemicals in drinking water and declare them hazardous substances.

Following this, water technology innovations have emerged to help tackle the problem.

Independent not-for-profit research technology organisation, Battelle, recently demonstrated its PFAS Annihilator™ Destruction Technology at a wastewater treatment plant in Michigan. 

A closed-loop on-site destruction solution powered by supercritical water oxidation, the system demonstrated its capability to mobilise and destroy PFAS chemicals that were present in the contaminated water.

As recently covered by Aquatech Online (5 solutions to remove PFAS from water), other solutions include carbon filtration, IX, Plasmatron, supercritical water oxidation and reverse osmosis membranes.