NPDES Permit #SC0001848
Westinghouse is permitted to discharge treated wastewater to the Congaree River under a National Pollutant Discharge Elimination System (NPDES) permit issued by DHEC. This permit sets monitoring requirements and pollutant limits, as necessary, on the effluent from the wastewater treatment system. After extensive technical review, a new five (5)-year NPDES permit was drafted for the facility. The proposed draft permit underwent a thirty (30) day public comment period ending in October 2019 and a second thirty (30) day public comment period ending in June 2023. All comments received during both public notice periods were taken under consideration. The permit was issued September 15, 2023.
Flow, ultimate oxygen demand (UOD), dissolved oxygen (DO), biochemical oxygen demand (BOD5), pH, total suspended solids (TSS), total nitrogen, ammonia-nitrogen, nitrate nitrogen, phosphorous, fluoride, uranium, total residual chlorine (TRC), mercury, oil & grease, E. coli, and whole effluent toxicity (WET) are currently monitored in the permit.
Also, through the NPDES permit, groundwater in the vicinity of the wastewater treatment facility is monitored for nitrate-nitrogen, fluoride, uranium, technetium-99,semi-volatile organic compounds (SVOCs) (including bis(2-ethylhexyl) phthalate, naphthalene, tributyl phosphate, and others measured by EPA Method 8270), pH, turbidity, and specific conductance.
- NPDES Permit
- Fact Sheet & Permit Rationale
- NPDES Final Determination Letter
- Response to Comments
- Guide to Board Review
Fish Tissue Study
Bluegill sunfish (bream) were collected from the Congaree River and analyzed to indicate if the fish are accumulating uranium and fluoride due to the Westinghouse effluent discharge that would demonstrate an environmental monitoring response relative to water quality concerns or public health protection concerns upon consumption of the fish by recreational and/or subsistence fishermen.
Bluegill sunfish was chosen for the study because work published by others indicated that this species’ food source (insects) makes it an early indicator of uranium uptake and because it is also commonly consumed by those who fish on the Congaree River. Field conditions determined the size of the fish but the goal to use pan size was met. Pan size is the size fish one would normally catch for consumption, approximately 5-10 inches for bluegill.
Fish were collected from the Congaree River at three (3) locations – near downtown Columbia; at/around the Westinghouse wastewater treatment facility effluent diffuser; and, just upstream from its confluence with the Wateree River.
For complete details of the sampling and analyses performed, please read the entire report that can be found here:
Within the context of the point-in-time of sample collection, target species and analytical methods:
- The target species of bluegill sunfish was indicated to be healthy from an ecological viewpoint.
- No signal for uranium from the Westinghouse facility was discerned.
- A slight, apparent signal for fluoride was observed at/around the Westinghouse wastewater diffuser but it was not overall significantly different (statistically) from the other two (2) locations.
- Based on the whole fish dataset as an environmental monitoring sentinel, neither uranium nor fluoride was indicated to be contaminants of concern for ambient water quality.
- Based on the filet dataset as a public health monitoring sentinel, neither uranium nor fluoride was indicated to be contaminants of concern for human consumption of bluegill sunfish.
Based on the results obtained from this study, additional evaluation is not presently planned. This decision will be re-visited should new information prompt renewed concern.