Dayton stopped pumping drinking water at seven groundwater wells at the Huffman Dam well field last April where an early warning groundwater monitoring network showed per- and polyfluoroalkyl (PFAS) substances city officials believe were part of a contamination plume migrating from Wright-Patterson Air Force Base.
The two sources of separate contamination could eventually poise a threat to dozens of city groundwater wells in the Mad River well field, Dayton authorities said.
RELATED: Dayton demands Wright-Patt act on water concerns
The Huffman Dam and Tait’s Hill well fields — more than three miles apart — are the “bookends” of the city’s Mad River well field system that counts more than 60 groundwater drinking wells, officials said.
“Ultimately, we absolutely have to have resolution on how to contain that contamination so that it doesn’t get into the rest of the Mad River well field and then treat it with a cleanup,” said City Manager Shelley Dickstein. “Down the road, if we did nothing the entire well field would be at risk.”
Ohio EPA Director Craig Butler sent a Feb, 21 letter to Dayton, saying the state agency was “disappointed” the city had not shared the information with the agency about the fire training center before mid-February, but was confident Dayton would act to address the contamination.
“It is more critical than ever that Dayton be more forthright with sampling results and data as this investigation progresses to ensure Dayton’s drinking water is protected,” he wrote.
Among other instructions, the Ohio EPA ordered the city to test treated water at its Ottawa treatment plant monthly for PFAS beginning March 31 and raw water at least quarterly.
If Dayton detects PFAS contamination over the threshold level of 70 parts per trillion in monitoring well between the fire training site and the operating production wells, it must alert the Ohio EPA and sample the production wells closest to the contamination, Butler added.
Dayton also must determine if the firefighting training site is the source of detected PFAS levels of less than 10 parts per trillion at the Ottawa treatment plant by submitted a work plan by April 30, Butler wrote.
A city spokesman was not able to immediately comment late Thursday.
City leaders have urged the Air Force to act more quickly to prevent contamination of the Huffman well field and reimburse the city nearly $1 million in costs for testing and studies.
Wright-Patterson spokeswoman Marie Vanover said Thursday base authorities did not know about the contamination at the city’s firefighting training site until Wednesday.
The base continues to study the extent of contamination and has demonstrated a commitment to identify and mitigate groundwater contamination, she said in an email.
“We will continue to evaluate potential impacts to the drinking water and will work with our local and state partners to develop defensible work plans to do so,” she added. “The Air Force is committed to protecting human health and the environment and we are working aggressively to ensure our installation and supporting communities have access to safe drinking water.”
Dayton says the water it distributes to residents is safe, and it has not detected the contaminant in treated water, according to Michael Powell, city water department director.
As a safeguard, Dayton shut down the dozen production wells at the two sites to avoid drawing contamination further into the groundwater, said Deputy City Manager Tammi Clements.
A May 2017 sampling of groundwater monitoring wells at Tait’s Hill found at least one sample registered 1,200 parts per trillion – similar to hot spots found inside Wright-Patterson, Dayton officials said. The Environmental Protection Agency health advisory threshold for lifetime exposure in drinking water is 70 parts per trillion.
RELATED: Wright Patt treating tainted water in contaminated drinking wells
Dayton reported it discovered polyfluroalkyl substances at less than 10 parts per trillion for the first time in the raw water intake of its Ottawa water treatment facility near the Mad River last November.
Huffman groundwater wells stand about a half mile from the base boundary and is also north and upstream of the city’s firefighting training site, one of the reasons city officials said they contend Wright-Patterson is the likely source of contamination migrating toward Huffman. A city-owned early warning system of monitoring wells at Huffman detected at least one sample with 35 parts per trillion of the contaminant, according to the city.
“The early warning network did exactly what it was supposed to do,” Clements said. “It warns us in enough time that we can mitigate a problem before it actually reaches the (drinking) production wells.”
Dickstein outlined the two sources of contamination in a Feb. 21 letter sent to city managers.
RELATED: City stopped pumping water from well field near Wright-Patt
The latest communication followed a Feb. 7 letter she sent to city managers in the region, asking them to co-sign a letter urging Wright-Patterson to reach more quickly to prevent the contamination of the Huffman well field and an aquifer three million people rely on.
The city, thus far, has had a mixed response to the plea.
Dayton has nearly 200 groundwater wells and two water treatment plants spread among three primary well fields.
Along with the Mad River well field, the others include Miami and Rip Rap Road well fields near the Great Miami River.
The city has a capacity to pump nearly 200 million gallons daily, but typically pumps less than 60 million gallons a day, according to Clements.
PFAS substances are found in consumer products from clothing to cookware, but were also used in firefighting foam.
The U.S. EPA reported human epidemiology and animal testing studies indicate exposure to the contaminant suggest it may be responsible at certain levels for testicular and liver cancer; changes in cholesterol; low birth weight in newborns; liver tissue damage; and effects on the immune system and thyroid.
About the Author