• State to Duke: Get camera scans of ash pond pipes.
State officials told Duke Energy on Wednesday to do video inspections of all pipes at the ash ponds near 14 of its current and former coal-fired power plants.
"The agency will request that Duke Energy use cameras to video the insides of all pipes at the facilities and provide the videos to the state," the N.C. Department of Environment and Natural Resources said in a news release.
The DENR has taken a more vigilant approach to Duke Energy's 30-plus ash ponds since the Feb. 2 spill of massive quantities of coal ash at its retired Dan River power plant in Eden.
In years past, state officials received several engineering reports dating back to the late 1990s that urged monitoring drainage pipes under the two-pond, Dan River ash basin and
possibly examining them with robot cameras.
Those suggestions were never acted upon because Duke officials said water coming from the pipes did not appear dirty, a sign of leakage into the pipes that could suggest structural problems. But one of the Dan River pipes ruptured last month, causing the huge spill, and the other was later found to have a major leak.
An inspection by a robot camera confirmed problems with the second pipe.
Meanwhile, the spill continued to affect downstream communities as a hazardous-materials unit in Danville, Va., responded to calls about a suspicious substance in the river. The team was summoned to the area near the Union Street Bridge to investigate a deposit that struck observers as unusual, said Steve Dishman, assistant fire chief for the community 20 miles down river from last month's spill. It turned out to be coal ash, Dishman said.
Back in North Carolina, the DENR's latest move apparently stems partly from reports Duke submitted to state regulators recently, acknowledging that eight of its ash ponds have some amount of piping made of corrugated metal.
The Dan River pipe that collapsed was metal and less durable than reinforced concrete, the other common material used in making such pipes. Previously, Duke asserted that the Dan River facility was the only one with such metal piping.
State officials said Wednesday that although that belief didn't pan out, Duke apparently was correct in earlier statements that the Dan River ponds are the only ones with drainage pipes running directly beneath the pools of stored ash.
Coal ash results from power plants that burn pulverized coal to produce electricity. It includes heavy metals and other contaminants that can be harmful to humans, fish and wildlife.
DENR officials announced their decision to seek across-the-board video monitoring of all ash pond pipes as part of a larger initiative in which regulators plan next week to "conduct detailed inspections of all Duke Energy's coal ash facilities in North Carolina."
"During our (earlier) visual inspections, we did not see any discoloration or cloudy water that you would typically see if wastewater was leaking into the spillway pipes," said Tracy Davis, director of the DENR's division of energy, minerals and land resources. "However, running cameras through every pipe and getting the plans for each site will give us a much better understanding of the construction of those spillway pipes."
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