Initial water tests performed at a small number of control wells in the state show metals contaminants at similar levels to those found in wells near Duke Energy coal ash ponds, state environmental officials say.
The N.C. Department of Environment and Natural Resources is testing wells that are generally in the vicinity of Duke coal ash disposal sites but have no groundwater connection to water from the sites.
This is being done to determine what levels of contaminant associated with coal ash can be found in the background levels of water that appears not to be affected by the coal ash ponds.
Duke spokeswoman Erin Culbert says the testing to date supports Duke’s contention that the contaminants found in hundreds of wells within 1,500 feet of Duke coal ash ponds in the state also occur naturally in the state’s ground water.
“This to be another important piece of data to be considered,” she says. “Our position is that it generally validates our contention that these contaminants are found in naturally occurring levels.”
The N.C. Department of Health and Human Services have reacted to the results the same way they reacted to the wells near the ponds. Out of 24 wells tested, DHHS issued “do not drink” recommendations to owners of 20 of the 24 control wells tested to date.
DHHS in May and June had issued warnings to the owners of 191 wells within the 1,500 foot limit of Duke ash ponds that they should not drink the water from the wells. That was of 207 wells tested. At issue were the levels of two contaminants — hexavalent chromium and vanadium. The state has no specific standard for determining a safe level of those metals in well water. So DHHS has followed its policy of using the strictest standard available, issuing recommendations not to drink the water if the contaminants rise to the level that cause a one in a million chance of causing cancer in an individual. That level is far lower than federal standards for those contaminants in community water sources such as municipal water systems.
Last month, DENR issued what it called “a health risk explanation” for residents who had received the “do not drink” recommendations. DENR said the explanation was an attempt to put the danger presented by the metals in the wells in perspective.
DENR cited several statistical risks that were significantly higher than those posed by the well water, including a contention that a person would be eight times more likely to be killed by a lightning strike (a 1 in 136,011 chance) than getting cancer from the well water.
That won DENR some criticism from people in the affected areas and state environmental groups. Frank Holleman, a senior attorney for the Southern Environmental Law Center, said DHHS was the proper authority to assess the risks.
“DENR’s job is to make sure that water is not polluted to unsafe levels,” he says. “They are not there to minimize the warnings issued by Health and Human Services.”
DHHS does not challenge the statistics offered by DENR. But it stands by its recommendations.
“Risk assessment is understood by different people in different ways. For some, these comparisons will make sense; for others, they may not,” says spokeswoman Alexandra Lefebvre. “However, because every Health Risk Evaluation is highly individualized, DHHS continues to provide individual consultations about the recommendations they have received.”
But the new water testing appears to show at least that however the risk is understood, it may not be limited only to wells that may be affected by Duke ash ponds.
DENR says in a blog posted Monday “the study provides a limited evaluation of the distribution of metals … that may be naturally occurring in the groundwater.” But it notes that the limited number of wells were all in the region of Duke’s Allen, Buck and Marshall steam stations. DENR is continuing to do tests of wells in the regions around all 14 current and former Duke coal plants.
Monday’s results were simply the first available so far.
Duke will continue to provide bottled water to the owners of the 191 wells that may have had their water impacted by Duke’s ponds. But Duke is not providing water to the owner of the control wells.
It is not clear what steps those people who received the most recent warnings should take. DHHS officials have conceded that the levels being found in the wells are probably below what can be removed by filtration systems. Meanwhile Duke continues to assist with water sampling and analysis to determine whether the 191 initial wells are impacted by contaminants from the ash ponds.
Culbert says Duke expects to have that work completed by mid September. She said Duke will continue to provide bottled water to those well owners until a determination is made whether Duke is responsible for the contamination.
“We will give several weeks notice before any decision on whether to discontinue providing bottled waters so that the residents can plan accordingly,” she says.