DENVER — Dozens of water sources across Colorado would be considered unsafe under newly-proposed Environmental Protection Agency limits on so-called forever chemicals, or PFAS.
The EPA on Tuesday proposed maximum contaminant levels of 4 parts per trillion. The 4 parts per trillion threshold had been identified as the highest acceptable level in a health advisory last June.
Under the latest proposal, PFAS levels would be enforceable under the Safe Drinking Water Act – legislation that regulates more than 90 contaminants in American drinking water.
In 2016, the EPA had set safe PFAS levels at 70 parts per trillion.
What the heck are PFAS and why are they suddenly a big deal in Colorado?
Tests of more than 100 public drinking water sources in Colorado showed traces of PFAS in 2020, according toThe Denver Post.
PFAS (polyfluoroalkyl and perfluoroalkyl substances), also known as "forever chemicals," are a group of man-made chemicals that have been used in industry and consumer products since the 1940s because of their useful properties, according to the EPA.
For context, we’re talking about an incredibly small amount of these harmful compounds.
“One part per trillion is the equivalent of one drop of dish detergent in the amount of dishwater that would fill a railroad car train ten miles long,” Martin Kimmes, the water treatment and quality manager for the City of Thornton, told Denver7 last summer.
He said a tool to measure that small of an amount doesn’t even exist.
The federal proposal would have sweeping effects across the country, but Colorado could be impacted more than most.
A 2021 study by Public Employees for Environmental Responsibility (PEER) found that Colorado may have the most PFAS-contaminated sites of any state in the U.S. At the time, the EPA had identified roughly 21,000 sites in Colorado that were “handling PFAS” – thousands more than any other state.
The agency found around 120,000 such sites across the country.
Last year, Thornton reported PFAS levels in its water system that were more than 1,300 times the acceptable level. Englewood had more than 600 times the acceptable level in its water system.
Other water providers that showed a high concentration of the chemicals included Arapahoe County, Aurora, Brighton, Crowley County, Sterling, Englewood, Frisco and Lafayette, according to The Denver Post.
You can search water providers' PFAS levels in the tool embedded below or here, courtesy of The Post.