Denver officials filed a lawsuit against the Colorado Department of Public Health and Environment claiming the agency illegally shoehorned new wastewater permit conditions to include regulating so-called PFAS “forever chemicals” at Denver International Airport in violation of state law.

The permit, issued in 2012, is being renewed by CDPHE with new and amended requirements for stormwater discharges, according to Denver’s court filing.

Denver alleges the new requirements don’t fit under the umbrella of the existing permit and that imposing those conditions as part of a permit renewal would cost the city “a significant amount of work and expenditures,” including “many PFAS-related requirements that are vague and unfeasible.”

David Steinberger, senior assistant city attorney in the airport section, told the Denver Gazette in an interview that the challenges faced by the airport in complying include a permit condition that says that no firefighting equipment that discharges any PFAS can be used.

“With respect to PFAS specifically, at its core, we think the agency is trying to use the stormwater permit as a way to regulate PFAS at the airport in a way that exceeds their authority,” Steinberger said.

Denver attempted to appeal the new conditions and claims that CDPHE dodged the issue by excluding the permit terms Denver asked to be considered by narrowing the “scope of the hearing,” and without any explanation as to why the department would not consider the matter, which Steinberger characterized as arbitrary.

The chemicals involved are group of per-and poly-fluoroalkyl “forever chemicals” collectively called PFAS that have recently become a hot-button issue because of their ubiquitous presence in both the environment and in humans. Scientists say that nearly every person on earth has some amount of PFAS in their bodies because it is widely used in manufacturing a wide spectrum of consumer products including cookware non-stick coatings and plastic products.

According to the Agency for Toxic Substances and Disease Registry — a federal public health agency of the U.S. Department of Health and Human Services — research involving humans suggests that high levels of certain PFAS may lead to increased cholesterol levels, decreased vaccine response in children, changes in liver enzymes, increased risk of high blood pressure or pre-eclampsia in pregnant women, small decreases in infant birth weights, and increased risk of kidney or testicular cancer.

ATSDR emphasizes the word “may” in its report, adding: “At this time, scientists are still learning about the health effects of exposures to mixtures of different PFAS.”

One of the major sources of pollution now being found in many areas is aqueous film forming foam (AFFF) used, among other fire departments, at airports all over the country for fighting fuel fires in aircraft crashes. Since the 1970s, AFFF has been used both for firefighting and training.

The airport is still using AFFF firefighting foam with PFAS because FAA regulations require the use of military-specification foam and the new style foam is still under development and has not yet been approved by the FAA.

This, Steinberger said, creates a nearly impossible situation even when the airport converts to a fluorine-free firefighting foam, as it intends to do.

“For instance, one of the requirements in the permit is that, you can’t discharge out of firefighting equipment if there may be any residual PFAS in that equipment,” said Steinberger. “And that’s an impossible standard because once PFAS is in a piece of equipment, it’s going to be very hard, if not impossible, to ensure that there will be no residual PFAS in that system, especially because we’re looking at such small amounts of PFAS that get regulated. I mean, we’re testing into parts per trillion.”

One unfeasible path to compliance with the permit, Steinberger said, would be to replace the entire firefighting fleet and scrap the current equipment.

“We would like more dialogue with them. I mean, I think no one wants to be in litigation,” said Steinberger. “I think there’s a lot of opportunity for us to work collaboratively to find common sense approaches that meet their goals, but also do it in a way that will actually work for an airport.”

Forever chemicals were found in the water and soil in the Security-Widefield area near Colorado Springs in 2013 and were determined to be caused by the historic use of firefighting foam at Peterson Air Force Base according to a report by the Agency for Toxic Substances and Disease Registry.

The ATSDR issued a nationwide report on PFAS contamination last year and the Environmental Protection Agency issued a health advisory drastically lowering the agency’s recommendations on safe limits for drinking water.

The EPA set a new non-regulatory lifetime health advisory level recommendations at 0.004 parts per trillion (ppt) for PFOA and 0.02 ppt for PFOS, the two most prevalent types of PFAS. The previous EPA recommendation was concentrations of 70 parts per trillion. An EPA fact sheet described the new health advisory levels as “below the levels at which analytical methods can measure PFOA and PFOS.”

On July 5, 2023 the United States Geological Survey released a report saying: “At least 45% of the nation’s tap water is estimated to have one or more types of the chemicals known as per- and polyfluorinated alkyl substances, or PFAS.”

The USGS says “there are more than 12,000 types of PFAS, not all of which can be detected with current tests; the USGS study tested for the presence of 32 types.

CDPHE spokesperson Kaitlin Beekman said: “We do not comment on pending litigation.”