Badin Business Park has formally submitted an application to renew its NPDES (National Pollutant Discharge Elimination System) permit. The 144-page application was submitted to the NC Department of Environmental Quality’s Division of Water Resources on April 25, 2022.
The current permit, which authorizes discharges into Badin Lake and an unnamed tributary to Little Mountain Creek, expires on October 31, 2022.
In the permit application, Badin Business Park has asked DEQ to consider two minor modifications related to stormwater discharges: (1) the removal of monitoring requirements and discharge limits for trichlorethylene at two outfalls; and (2) the ability to use “grab samples” in lieu of 24-hour composite samples for chronic toxicity at Outfall 012.
The first change is requested because trichlorethylene has never been detected at the two outfalls (Outfalls 011 and 012) and there is not a reasonable potential of exceeding the trichlorethylene water quality standard.
The second request, regarding chronic toxicity sampling at Outfall 012, involves “grab” sampling rather than composite sampling. Current requirements call for one sample taken during the first two days of discharge and a second sample taken during the third, fourth or fifth day of discharge.
“Discharge at Outfall 012 is largely driven by stormwater, and, as a result, is intermittent, infrequent, and typically of short duration,” the permit application explains. “Discharge at this outfall commonly ends before the second composite sample can be collected, resulting in an invalid test. Converting to a ‘grab’ sample for chronic toxicity at Outfall 012 could reduce the likelihood of an invalid test.” The application states that North Carolina’s toxicity test procedures allow for the use of “grab” samples in lieu of 24-hour composite samples if approved in a facility’s permit.
DEQ is currently reviewing the Badin Business Park’s permit application for completeness. Once complete, it will develop a draft NPDES permit for public review and comment. The timing for the development of the draft permit will be determined by DEQ.
Badin Business Park currently monitors and reports stormwater and groundwater discharges at 11 outfalls, or drainage areas, around the former Badin Works smelter each month.