RALEIGH, NC (WBTV) - The North Carolina Department of Environmental Quality adopted new performance standards for private water wells despite objections from epidemiologists at the North Carolina Department of Health and Human Services.
On Friday, DEQ announced new performance standards for water filtration devices that allow for levels of a toxic chemical called hexavalent chromium more than ten times the health screening level used by health scientists at NCDHHS.
DEQ set the new performance standards as required by the Coal Ash Management Act, which requires Duke Energy to provide an alternate source of drinking water to residents with drinking water wells near Duke coal ash ponds that have been found to contain elevated levels of hexavalent chromium.
Duke Energy is providing water filtration devices to some households where the well water was deemed unsafe to drink.
Residents who lived near Duke coal ash ponds received "do not drink" letters from state regulators in 2015 if their well water was found to have a level of hexavalent chromium of .07 ug/L or higher. That standard was later rescinded by political appointees at DEQ and NCDHHS who worked for then-Governor Pat McCrory.
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The new filtration devices will have to provide water that meets the new performance standards set by DEQ.
The new standard fails to set a specific limit for hexavalent chromium and, instead, only gives a standard for total chromium. There are two variations of chromium: chromium3 and chromium6; only chromium6 - more commonly known as hexavalent chromium - is considered toxic.
Scientists with the NCDHHS Occupational and Environmental Epidemiology Brach pushed back against DEQ's decision to only set one standard for total chromium in a memo prepared in April 2017.
"North Carolina (NC) Department of Environmental Quality (DEQ) stated that they will use exclusively 10 ug/L total chromium (including hexavalent chromium) as a performance standard for the evaluation of private drinking water wells treatment technologies," a draft of the memo obtained by WBTV reads.
"The basis of this position is that DEQ does not have confidence in the draft EPA IRIS cancer slope factor (CSF) for hexavalent chromium because of the comments in the draft document and they believe 10 ug/L is sufficient to protect the people with coal ash management act (CAMA) affected private drinking water wells."
The memo goes on to say that the epidemiologists at NCDHHS will continue using the previous standard set for hexavalent chromium in 2015 and criticizes DEQ's decision to not use the same standard.
"It is not health protective from exposure to a mutagenic carcinogen such as hexavalent chromium," the memo states.
But a press release announcing the new standards issued by DEQ on Friday sounds a different tune.
"We want every family in North Carolina to have access to safe, clean drinking water," DEQ Secretary Michael Regan said. "We've set performance standards for coal ash contaminants to ensure that families who use these filtration systems will have water that meets or exceeds federal and state standards."
At his confirmation hearing to assume the helm at DEQ earlier this year, Regan did not directly answer a question about what the appropriate level of hexavalent chromium in water should be.
"We're trying to ascertain the right level of data to set that standard. Those are ongoing conversations," Regan said. "We are not there yet."
Spokesmen for DEQ and NCDHHS issued the following joint statement in response to questions from WBTV on Tuesday afternoon: