Ontario government says PFOS continues to be found in Glanbrook streams
Ontario's Ministry of the Environment, Conservation and Parks confirmed that perfluorooctane sulfonate is still leaching from the Hamilton International Airport above the threshold numbers.
Gary Wheeler, spokesperson for the ministry, stated in a series of email responses to questions that PFOS, a synthetic chemical part of a class called PFAS (perfluoroalkyl and polyfluoroalkyl substances) that the contamination continues to migrate" from the airport at levels above the agreed upon threshold."
The ministry has required the airport to provide a plan for further mitigation measures to reduce the levels of PFOS, he said. The airport conducts monthly inspections of the former firefighting area, has maintained the integrity of a cap installed on the former pad and ensured a vegetative cover to mitigate potential erosion.
In 2022, additional mitigation measures took place, including dewatering and decommissioning of an existing stormwater retention pond at the former site, installation of a permeable soil cap over the pond and surrounding ditches, and restoration of topsoil and vegetation.
A mitigation summary report outlining the activities was submitted to the ministry in January. It is expected that surface water sampling will be completed in the spring to determine if the mitigation effort has been able to stop the outflow.
The ministry publishes fish consumption advisories that have incorporated PFOS contamination results for years. The advisories suggest some fish in Lake Niapenco, including bass, catfish and crappie, should not be consumed at all by children and women of child-bearing age.
The Niagara Peninsula Conservation Authority stated in a 2020 water quality monitoring program report that evidence of PFOS is present in Lake Niapenco, but not at concentrations above Health Canada drinking water guidelines." The report stated these chemicals will continue to be present" in Lake Niapenco due to the delay to contain upstream sources."
Wheeler also confirmed that the Ontario government is working with" the federal government and other provinces on detailing new Canadian guidelines for PFAS after the United States's Environmental Protection Agency announced it will be lowering the PFAS levels in drinking water.
Wheeler said since 2017 the province has been providing interim advice for the evaluation of PFAS contamination in drinking water.
We will consider the approaches of the Canadian government and the U.S. Environmental Protection Agency once they have been finalized," said Wheeler.
The EPA announced in March it is proposing to limit the amount of harmful forever chemicals" in drinking water to the lowest level tests can detect. Officials said, if adopted, the guidelines will save thousands of lives and prevent serious illnesses, including cancer.
It is the first time the EPA has proposed regulating a toxic group of compounds that are widespread, dangerous and expensive to remove from water.
Dr. Joe Minor, who raised the issue of PFOS leaking into the ground near the airport after sampling a stream that runs under Airport Road in 2011, said the worst polluted locations are around the places where the PFAS were manufactured."
But there are other toxic hot spots" that have PFAS levels higher than background levels and are mainly down stream of airfields where the chemical was sprayed in huge quantities" for firefighting.
It is important to deal with these government-created toxic hot spots because they continue to release amounts of PFAS that are above background levels," said Minor.
The ongoing risk assessment on the leaking chemicals began several years after local scientists found high levels in Lake Niapenco wildlife. Studies traced the now-banned pollutant, once used in firefighting foam, to a 1980s-era training pad at Hamilton's airport.
Hamilton International Airport over the years has instituted several mitigation efforts to dig out and cap the training pad starting in 2019. Aviation firefighting foam contained PFOS until a voluntary phase-out production in 2002, stated the airport. The foam was used for training purposes from 1985 to 1989.
A federal study has been examining the downstream impact of the chemicals along the Welland River from the airport as far as the eastern end of Lake Niapenco in Binbrook. The chemicals are believed to travel through ditches and creeks into the river.
Hamilton public health conducted testing of area wells in 2012 and found no concerns.
Minor has urged the Niagara Peninsula Conservation Authority to identify the PFAS problem at Binbrook. He said it took years before the authority adopted a catch and release policy, but it was only encouraged." He also said there was no mention of any contamination problem.
The authority has a do not consume fish" statement on its website, but does not mention PFAS contamination.
At the NPCA's September 2022 board meeting, several citizen members urged the authority to post clear fish consumption warnings.
The problem with PFAS pollution is that it is very persistent in the environment. PFAS pollution lasts longer than the attention spans of local governments," Minor said. When communications are updated any mention of the problem gets lost."