SOUTHPORT — Environmental advocacy groups are concerned with the makeup of potentially harmful wastewater being discharged by a steam electric power plant in Southport. In a joint letter, the groups acknowledge some new provisions in the discharge permit represent improvements but overall, say it’s “far too lax.”
Capital Power shares a wastewater discharge canal with Duke Energy’s Brunswick Nuclear Plant and has operated on an expired (but administratively extended) National Pollutant Discharge Elimination System (NPDES) permit for years; in April 2016, the company applied to renew the permit; over three years later, the state issued it a draft permit in June.
In August, the Southern Environmental Law Center (on behalf of Cape Fear River Watch, North Carolina Coastal Federation, the Sierra Club, and the Brunswick Environmental Action Team) submitted a lengthy response to the company’s draft NPDES permit, and in September, to its stormwater permit, which releases stormwater out the same outfall location.
In both instances, the SELC urged the Department of Environmental Quality (DEQ) to strengthen its discharge requirements.
The DEQ is hosting a public hearing on the permits Thursday at 6 p.m. at Brunswick Community College in Bolivia.
Capital Power, or CPI USA North Carolina LLC, is a 88-megawatt power plant that burns coal, tires, and wood to produce steam. Capital Power sells steam to Archer Daniels Midland and electricity generated by its superheated steam to its neighbors at Duke Energy’s Brunswick Nuclear Plant.
Capital Power releases its wastewater into Duke Energy’s often foamy water cooling canal that stretches around the city and ends at the Intracoastal Waterway, which makes its way into the Atlantic Ocean near Caswell Beach.
The discharge from both power plants is eventually emptied into a mixing zone less than one half-mile offshore on Caswell Beach. Capital Power’s direct outfall location releases wastewater just one quarter-mile east of N.C. 87, which crosses over the canal.
The plant employs about 50 people. Its continuous wastewater treatment operations consist of one distribution box and weir (Outfall 003) which transports wastewater from the plant’s fuel pile stormwater runoff, boiler room, cooling tower, demineralizer, sanitary runoff, reverse osmosis discharge, and floor sumps into two 500,000 gallon settling basins. Solids are to settle within these basins while nearly 400,000 gallons of wastewater is discharged daily.
Several concerns raised
SELC describes the treatment process as “not sophisticated” in its permit comments. The power plant’s omissions in its renewal application are “alarming,” according to the SELC, including omissions of outfall data at the sole discharge location into the canal which could be the only data point for understanding the concentrations of materials within coal bottom-ash transport water.
In its comments on the draft stormwater permit, SELC points out that according to monitoring data in November 2015, Capital Power discharged copper at a concentration as high as 26 micrograms, more than five times the acute water quality standard of 4.8 micrograms. Lead discharges are also a concern, according to the SELC, with discharges nearing chronic water quality standards.
Transformer oil likely containing toxic polychlorinated biphenyls (PCBs) and other potentially hazardous materials is exposed at the plant, which may be releasing residuals into the canal after rain events.
DEQ’s draft permit requires Capital Power to conduct a Pollutant Prevention Act (PPA) testing for 126 priority pollutants within six months of the next time it opts to renew or modify its current permit. This monitoring would occur once per permit cycle, according to the draft permit.
Environmental groups say the delayed and infrequent monitoring requirement for pollutants likely to be present in Capital Power’s wastewater is not acceptable.
“DEQ offers no reason for allowing this delay and none is obvious, particularly when three years have elapsed since CPI’s current weak permit expired,” SELC’s August letter states. “Furthermore, DEQ proposes to allow CPI to demonstrate compliance with the priority pollutant discharge prohibition through engineering calculations, rather than actually physically testing the wastewater. This is insufficient.”
Asked to generally respond to SELC’s comments and the possibility that wastewater would be tested for pollutants extensively after it was permitted, DEQ spokesperson Sharon Martin said the state welcomes feedback.
“All wastewater was characterized as part of this permit renewal, and we welcome the public input on the draft permits. All public comments will be weighed by staff at the close of the comment period before any final action is taken,” Martin said Tuesday.
DEQ’s public hearing on the Capital Power draft stormwater and NPDES permits will take place Thursday, Nov. 21, at 6 p.m. Speaker signup will begin at 5:30 p.m. in Building A at the Brunswick Community College in Bolivia.
View DEQ’s draft discharge permit for CPI below:
View SELC’s response to the NPDES discharge permit below (click full-screen mode to read):
Send tips and comments to Johanna Ferebee at firstname.lastname@example.org