Testimony by North Carolina’s state epidemiologist sheds light on discord among health experts on the decision to rescind do-not-drink advisories for wells near coal ash waste.
By Catherine Clabby
As state regulators prepare to release risk assessments of Duke Energy coals ash waste impoundments this week, a state health official divulged that some health officials opposed the state’s reversal of warning that drinking wells near the waste posed health risks.
Megan Davies, the state epidemiologist and epidemiology section chief in the Department of Health and Human Services, in sworn testimony also disclosed that politics, not just health-risk assessments, played a role in the March DHHS decision to back off from do-not-drink advisories for the wells.
The physician divulged too that she had reservations about the accuracy of the first line in the state’s safe-to-drink letters sent to well owners. It said: “We have reviewed the do not drink usage recommendation because we have determined your water is as safe to drink as water in most cities and towns across the state and country.”
Davies revealed this and more under oath during a pre-trial deposition taken May 4 by the Southern Environmental Law Center, which represents environmental groups in a lawsuit against Duke Energy regarding clean up of its coal ash.
DHHS leaders criticized release of Davies’ deposition. “It is misleading that the Southern Environmental Law Center would release partial information before our citizens have the complete facts,” said DHHS Communications Director Kendra Gerlach.
Crystal Feldman, deputy secretary for the state Department of Environmental Quality, agreed that the deposition is misleading. “Dr. Davies’ deposition only provides one viewpoint,” Feldman said.
SELC released a transcript of the deposition just days before the deadline – this Wednesday – when the DEQ is due to release risk assessments from coal ash impounded on 10 of 14 Duke Energy properties. The assessments could decide how fast and how aggressively clean up of the waste must occur on all sites.[pullquote_right]This is one of two stories about depositions given by state health officials over the coal ash situation. The other story is here.[/pullquote_right]Coal ash waste dumps at four sites already designated as high risk by the state’s Coal Ash Management Act must be excavated and closed by 2019. That includes the L.V. Sutton Energy Complex in New Hanover County, Dan River station in Rockingham County, Allen Steam Station in Gaston County and Asheville Steam Station.
Intermediate-risk sites must be excavated and closed by 2024; low-risk ponds must be closed, but not excavated, by 2029.
Better to wait
Well owners and environmentalists have criticized the DHHS and DEQ move in March to rescind 2015 DHHS advice that people not drink water in 320 drinking wells located near Duke Energy coal ash waste sites. That came after tests of the wells detected contaminants associated with coal ash, mostly hexavalent chromium and vanadium.
“The initial ‘do-not-drink’ advisory was a very cautious recommendation,” the March letter said. “In fact the recommendation regarding one of the elements is based on a potential one in a million risk for an average person consuming well water everyday for more than 70 years. Now that we have had time to study and review more data, we have concluded that it’s appropriate to return to drinking and using your water for cooking and other uses.”
Davies said she and Danny Staley, director of the DHHS Division of Public Health, favored waiting until the source of two contaminants in the well water was made clear before telling residents that drinking their water was safe.
Some well owners and environmentalists suspect coal ash is the source of both.
“We both felt it made more sense to wait on source determination,” Davies said under oath during her deposition. “That is relevant because if it were a contaminant, there might be ongoing contamination of wells with the increase in levels. So we felt we should wait until all the information was in and DEQ had made a determination, and then communicate with the well owners in that full context.”
DEQ has said groundwater, the primary source of well water, has been contaminated underneath all of the Duke Energy properties with coal ash waste but the risk of the contamination to drinking water is not clear. DEQ’s assessment of whether contaminants from coal ash could reach drinking wells is one thing that state risk assessments expected this week could clarify.
Politics in play?
The picture Davies paints of discussions among state health officials is more complex than the policy-focused description that DEQ Assistant Secretary Tom Reeder described recently.
“DHHS went back and revised original health-risk evaluation. They decided to make their recommendation consistent with federal safe drinking-water rules,” Reeder said while giving a talk last month at UNC-Chapel Hill.
Davies said Randall Williams, deputy secretary of health services, shared her worry that people advised to drink water from other sources would experience stress as a result, a potential health threat. But Williams also voiced concern that state legislators might limit state public involvement in assessing well water if the letter was not dispatched.
“So was Dr. Williams concerned that if you did not send out a ‘do-not-drink’ letter, that members of the General Assembly might restrict the administrative authority of the Department of Public health?… Did he express that concern?,” asked Frank Holleman, senior litigator for the SELC.
“Yes,” answered Davies, whose organization issued do-not-drink advisories based on screening levels established by state epidemiologists.
Two bills introduced in the House and Senate after the letters were sent would limit local, county and state officials from releasing health advisories for wells and public drinking water to cases where federal or state regulatory contaminant standards are exceeded.
Davies stressed that she did not favor releasing a letter that said the well water was as safe to drink as most public water systems in the state and the country, which are regulated by federal standards, when the letter did not disclose to well owners that federal rules do not yet regulate hexavalent chromium or vanadium in drinking water.
Safe as what water?
Also, the claim that well water was as safe as most public drinking-water supplies contradicted what she’d seen regarding levels of hexavalent chromium in public drinking water in Raleigh and Charlotte, which were lower than those detected in some wells near coal ash sites, Davies said.
“They are, on average, lower than those measured … in the drinking wells under the [Coal Ash Management Act] sampling,” Davies said.
California and North Carolina share the lowest groundwater standard for hexavalent chromium in the country. The standard, 10 parts per billion, is used to determine levels at which polluters must clean up. Only eight states in the U.S. have groundwater standards for vanadium; North Carolina’s is 8 ppb.
Drinking water contaminated with hexavalent chromium has been associated with increased risks of stomach tumors, Davies said during her testimony. Vanadium has been observed to create effects to kidneys and blood cells in toxicological studies of lab animals, she said.
Holleman queried Davies closely on discrepancies between the March letter’s claim and sampling of well water in Salisbury, near the Buck Steam Station treatment plant. One well test found levels of hexavalent chromium of 21.8 micrograms per liter, about 300 times more than the state screening level, Holleman said, citing a state notification to the well owner.
“Would you agree that this gentleman’s well water is less safe than the well water in Salisbury?… This well water has more hexavalent chromium in it, and therefore a higher associated risk for the adverse health effects of hexavalent chromium, which is cancer, right?” Holleman asked.
“Yes,” Davies said.
“And would you agree, therefore, the water in this gentleman’s well is not as safe as the drinking water at the Salisbury Public Water System, which has less than one parts per billion?,” he asked.
“Based on the hexavalent chromium level, yes,” Davis answered.
In cross-examination, Brent Rosser, a Charlotte attorney representing Duke Energy, emphasized the low increase in cancer risk represented by the state’s hexavalent chromium screening level.
“The one-in-a-million risk standard is higher than the lifetime odds of death from getting struck by lightning, a lethal dog bite, and a cataclysmic storm; correct?” Rossner asked.
“Yes,” said Davies.
“And, in fact, if my math is correct, the one in a million standard is over seven times more likely – or I guess you are seven times more likely to get struck by lightning and be killed than to develop cancer under the one in a million standard. Does that sound right?,” he said.
“Approximately, yes,” Davies responded.
Public health mission
But a second exchange with Holleman regarding the screening levels noted this: “The standard you used is the one in a million standard, which is the standard generally accepted in the field of toxicology and epidemiology; is that correct?,” Holleman asked.
“It is the standard laid out in the 2L Rule,” a state rule that regulates state groundwater quality, Davies responded. “And it is a generally accepted standard in the field of health-risk evaluation.”
Holleman also noted that the letters rescinding the do-not-drink orders referred to the state’s health mission of protecting North Carolinians.
“Now, the next to the last sentence says, ‘Our mission at the Department of Health and Human Services and the Department of Environmental Quality is to protect the health and safety of all North Carolinians.’ Do you believe this letter supported that mission or was consistent with that mission?” Holleman asked.
Davies’ answer was one word.
Note: This article has been altered to add a response from the Department of Environmental Quality.
Safe To Drink Letter (PDF)
Davies Deposition (PDF)Z Smith Reynolds Foundation to examine issues in environmental health in North Carolina. [/box]