FAIRBANKS — Alaska’s Department of Environmental Conservation seeks to tighten the standards for per- and polyfluoralkyl chemical pollution in a set of regulation changes up for public comment through Nov. 5.
PFAS chemicals are found in many products, including nonstick pots, waterproof fabrics and high-end ski wax. In Alaska, the cause of most water pollution is an old fire suppressant known as aqueous film-forming foam. The substances are considered “emerging contaminants,” because they’ve been found to cause sickness in animals, but the extent of their risks to humans isn’t well understood.
PFAS can easily spread across property lines because they dissolve in water and move with underground water flows to pollute nearby wells. Since 2016, Alaska has required PFAS polluters to clean up the source of contamination based on the concentration of two perfluorinated chemicals, perfluorooctanoic acid, or PFOS, and perfluorooctane sulfonate, or PFOA.
The regulations up for comment this month add three additional chemicals to the list of substances that require cleanup when concentrations in groundwater reach a concentration of 70 parts per trillion, which represents about 3 1/2 drops of liquid in an Olympic-sized swimming pool. The three new chemicals are perfluoroheptanoic acid (PFHpA); perfluorohexanesulfonic acid (PFHxS); and perfluorononanoic acid (PFNA).
“Those compounds are similar in structure — 6 to 8 fluorinated carbons each — the evidence indicates that the compounds have similar biological half lives, which is indicative of toxicity. And the toxicity information, even though its limited, indicates that these compounds cause adverse health affects at similar doses as PFOA and PFOS,” said Sally Schlichting, a policy and regulations manager of the Alaska Department of Environmental Conservation in Juneau.
“More than one of these compounds may cause additive or synergistic health effects, which gives an additional reason of using the summed value,” she said.
In setting the standards for PFHpa, PFHxS and PFNA, Alaska is following the lead of Massachusetts and several other states, Schlichting said. The federal Environmental Protection Agency has standards known as lifetime health advisories for PFOS and PFOA, but not the other three chemicals.
The state environmental conservation department previously added the new chemicals to the standards for drinking-water wells with a memo in August. By making them part of the cleanup standards, the state would further require PFAS polluters to clean up the source of the chemical and to map the spread of the chemical in the groundwater.
Most of Alaska’s known PFAS contamination sites are in the Interior. The conservation department is monitoring firefighting foam cleanups at Eielson Air Force Base; the city of Fairbanks Regional Fire Training Center on 30th Avenue; Fairbanks International Airport; and at the old Williams Alaska Petroleum oil refinery in North Pole. A sixth site is outside the Interior, in the southeast Alaska town of Gustavus.
In Fairbanks, the city government has spent more than $3 million since 2016 testing water, delivering clean water and connecting properties with contaminated drinking-water wells to city water. In addition to drinking water for homes, the city has started providing irrigation water at the South Davis soccer fields, where concentrations of PFOS alone were more than 10 times the drinking water standard.
It’s hard to know whether any additional homes will need to be connected to city water based on the changing state standards, said Fairbanks city engineer Robert Pristash.
“To ask if there’s going to be more connections now, I don’t know how to answer that,” he said. “There is likely to be more, but (to find out) how may more, we have to figure out if we’re going to test (and) what the levels are going to be.”
He observed that for drinking-water wells, Fairbanks uses a standard of 59.5 parts per trillion, which is stricter than the EPA lifetime health advisory level of 70 parts per trillion. But because new cleanup rules regulate more than drinking water, they may affect people who use contaminated nondrinking-water wells to water plants.
In addition to the new cleanup standards for five of the chemicals, a separate standard will apply to water contaminated with a sixth PFAS, perfluorobutanesulfonic acid (PFBS), though it’s only considered harmful at much higher concentrations, 200 parts per trillion.
To read and comment on the new PFAS cleanup standards, visit bit.ly/2EaI5Ee.
Contact Outdoors Editor Sam Friedman at 459-7545. Follow him on Twitter:@FDNMoutdoors.
