State officials are concerned about the structural integrity of a second stormwater pipe located underneath a coal ash pond at Duke Energy’s Dan River plant. The pipe discharges into the Dan River about 100 yards downstream from a 48-inch pipe that spilled an estimated 39,000 tons of coal ash into the river last week.
Steve McEvoy, a dam safety engineer with the N.C. Division of Energy, Mineral and Land Resources, observed a number of deficiencies with the second, 36-inch pipe after reviewing a Duke Energy video inspection of the pipe interior.
Via the News & Observer:
A state inspector received the video from Duke during a visit to the site Tuesday. Company officials had indicated no serious problems with the second pipe, but when the inspector viewed the video Thursday he observed “infiltration … dripping and flowing” through leaky joints. At three different points, the inspector described what he termed as a “gusher.”
News & Observer - NC officials fear 2nd pipe collapse at Duke plant
The second pipe “has the potential by configuration to release ash material in a way similar to the 48-inch conduit,” McEvoy said in a letter to Duke Energy.
NC DENR has given Duke Energy ten days to come up with a plan and schedule to repair the second pipe.
“We’re concerned about the leaks we see in the 36-inch pipe and want to prevent a second pipe failure,” said Tracy Davis, director of the N.C. Division of Energy, Mineral and Land Resources.
Letter from NC DENR to Duke Energy, originally obtained by the Coal Ash Chronicles:
Charlotte Observer – Second pipe at Duke ash-spill site could break
Charlotte Business Journal – NC warns Duke Energy about second storm pipe under Dan River plant
In addition to the damaged pipe, a second possible leak at the Dan River site has been identified by the Waterkeeper Alliance and Yadkin Riverkeeper about a third of a mile upstream from last week’s massive spill.
Via the Waterkeeper Alliance:
On Thursday, February 6, Waterkeeper Alliance attorney Pete Harrison patrolled the spill site and noticed an unusual discharge flowing down an embankment at the southwest corner of of the plant’s coal ash impoundment.
“This area caught my attention because the rocks were stained bright orange and there was water cascading down, right into the river,” Harrison said. “When I paddled closer, I could see that the rocks had a thick, slimy coating, an indication of iron-oxidizing bacteria that is often present where seepage is bleeding out of coal ash pits.”
Harrison added, “The discharge concerned me because I’d reviewed the discharge permit for this facility and I knew that there wasn’t supposed to be anything coming out of the ash pond right there.” His team returned to the area four more times since last Thursday to see if anyone had attempted to stop it, but the discharge was still flowing unabated each time they went.
Waterkeeper Alliance – Ash pond still dumping while Duke begins ash removal from river
The group says that laboratory analysis of the discharge confirms coal ash pollutants well above human health and water quality standards, including high levels of arsenic and chromium.
Duke Energy and the EPA are conducting separate analyses of the water, but say the discharge is stormwater runoff flowing from a pipe that is not connected to the coal ash pond.
Via the Charlotte Business Journal:
He says Duke and the EPA decided “out of an abundance of caution” to test a sample from the runoff. The test was taken a couple of days ago, and Duke and the EPA are conducting separate tests on it.
The Waterkeeper Alliance says the water sampled by Duke and the EPA is not from the same site as the leak identified by the environmental group.
Harrison says neither the state or the federal agency was aware of the water discharge the alliance found until he asked officials about it at a public hearing the EPA held on Tuesday.
He contends the discharge he sampled, and has seen on five occasions since, is not the same one Duke is referring to.
Charlotte Business Journal – Feds testing water an environmental group says is a new leak from Duke Energy’s Dan River ash pond
Charlotte Observer – EPA to test Dan River for reported ash leak
NC DENR is also investigating a discharge of wastewater from the emergency pipe system installed in response to the Feb. 2 coal ash spill:
Duke Energy reported to DENR and the EPA that less than 1,000 gallons of wastewater reached the Dan River from an emergency piping system the company installed during its response to the coal ash spill. Duke installed the emergency piping system Feb. 9 to divert wastewater away from the coal ash pond that failed and into a separate, working coal ash pond at the Dan River Steam Station.
The company reported that the newly constructed emergency piping system, at one point, did not work as intended and a backflow from the emergency system got into an existing pipe connection at the site and discharged into the Dan River. Duke reported to environmental regulators that the wastewater released from the emergency piping system to the Dan River contained yard drainage water, basement sump water and treated domestic wastewater from sources outside either coal ash lagoon. The company reported that the existing pipe through which the back flow occurred was plugged when the company discovered the problem to avoid further discharges to the river.
The company reported that wastewater from the emergency piping system did not intersect with the coal ash waste and, therefore, the company reports that no coal ash waste made its way into the Dan River during the wastewater spill.
An unpermitted discharge of wastewater into waters of the state, such as the Dan River, is a violation of the Clean Water Act, which is enforced by the N.C. Department of Environment and Natural Resources. DENR’s investigation of this wastewater discharge will be included in the probe the state is conducting of the coal ash spill and any subsequent enforcement actions.