CHARLOTTE, NC (Bruce Henderson/The Charlotte Observer) - State health officials will lift their advice that hundreds of residents who live near Duke Energy coal ash ponds not drink their well water.
Tests last year found elevated levels of two elements, vanadium and hexavalent chromium, in private wells. Both occur naturally and in coal ash.
The N.C. Department of Health and Human Services last spring advised nearly 300 well owners, many of them in Gaston and Rowan counties, not to drink their water as testing continued. Duke says it is not responsible for the contaminants but has supplied residents with bottled water since then.
But the department said Tuesday that it's revoking that advice, as it relates to vanadium and hexavalent chromium, in letters that will go out this week.
The don't-drink advisories were based on temporary screening standards that HHS developed, on authority of the state coal-ash law, because state groundwater standards for vanadium and hexavalent chromium don't exist.
The state's health and environmental departments sparred for months over those levels, internal emails showed, with the environmental agency warning they were too low.
"Using an abundance of caution, we issued low levels that we knew were low levels," Dr. Randall Williams, deputy HHS secretary of health services, said in an interview Tuesday. "But we're also humble enough to revisit them and decided that, based on new information, we felt it was appropriate to change them."
A review of regulations elsewhere showed that neither the federal government nor most other states have set standards for hexavalent chromium, which is of concern because it may cause cancer, he said. The exception is California, whose standard is much higher than the screening level used in North Carolina.
Levels of the two elements above the state's screening standards also widely appear in public water systems, including Charlotte's, and in groundwater that is not affected by coal ash.
Most recently, that happened in Lee County, where coal ash will be disposed of in a former clay mine.
The state Department of Environmental Quality plans to recommend a groundwater standard for vanadium of 20 parts per billion, far higher than the .3 ppb level used in assessing the wells, Williams said.
The Environmental Protection Agency, which regulates only total chromium in drinking water, is reviewing whether to issue a separate standard for its hexavalent form.