15A NCAC 02B .0403 DEFINITION OF TERMS
(1) "Commission" means the Environmental Management Commission or its successor.
(2) "Conventional pollutants" means biochemical oxygen demand (BOD(5)), Total Suspended Solids (TSS), pH, fecal coliform, oil and grease, and any other pollutants the USEPA designates as conventional in applicable regulations.
(3) "Director" means the Director of the Division of Water Resources or Division of Energy, Mineral and Land Resources, Department of Environmental Quality, whichever is the permitting authority; or his or her designee.
(4) "Division" means the Division of Water Resources or the Division of Energy, Mineral and Land Resources, Department of Environmental Quality, whichever is the permitting authority.
(5) "Effluent limited" segment of a surface water means a segment that stream monitoring, assessment, modeling, or other analysis indicates is meeting applicable water quality standards or will meet applicable water quality standards after the application of minimum treatment requirements.
(6) "Minimum treatment requirements" means the minimum technology-based effluent limitations that a specific discharge would be required to meet in order to satisfy applicable treatment standards, including the following:
(a) "Secondary treatment" is the minimum standard of treatment for POTWs, as set forth in Rule .0406(a) of this Section.
(b) "Best waste stabilization pond technology" is the standard of treatment for waste stabilization ponds treating municipal or similar wastewaters only, as set forth in Rule .0406(a) of this Section.
(c) "Best practicable waste treatment technology," or "BPWTT," is an advanced standard of treatment for POTWs, as set forth in Rule .0406(a) of this Section.
(d) "Best practicable pollutant control technology," or "BPT," is the minimum standard of treatment for existing industrial dischargers, as set forth in Rule .0406(c) of this Section and in 40 CFR Chapter I, Subpart N – Effluent Guidelines and Standards.
(e) "Best conventional pollutant control technology," or "BCT," is a standard of treatment for existing industrial dischargers and typically applies to conventional pollutants, as set forth in Rule .0406(c) of this Section and in 40 CFR Chapter I, Subpart N – Effluent Guidelines and Standards.
(f) "Best available technology economically achievable," or "BAT" is a standard of treatment for industrial dischargers and typically applies to nonconventional and priority pollutants, as set forth in Rule .0406(c) of this Section and 40 CFR Chapter I, Subpart N – Effluent Guidelines and Standards.
(g) "New source performance standards" is the standard of treatment for industrial dischargers determined to be a new source pursuant to 15A NCAC 02B .0407.
Minimum treatment requirements must be met even if the receiving waters affected can or are expected to be able to accept higher pollutant‑load levels and still meet applicable water quality standards.
(7) "Nonconventional pollutant" means any pollutant not categorized as a conventional or priority pollutant parameter.
(8) "Oxygen consuming wastes" means those wastewater discharge components that are oxygen demanding in the aquatic environment. These are generally limited by BOD(5) and NH(3)‑N.
(9) "Priority pollutant" means any chemical pollutant listed in 40 CFR Part 423, Appendix A.
(10) "Publicly owned treatment works," or "POTW," means a treatment works owned by a State or a municipality and is as defined in 40 CFR 403.3. This regulation can be accessed free of charge at http://www.gpo.gov/fdsys/.
(11) "Settleable solids" means the volumetric measurement of solids determined in the following manner: place one liter of the wastewater in a standard Imhoff cone and allow to settle for 45 minutes. After 45 minutes settling, stir the liquid layer, taking care not to disturb the solids already settled, and allow to settle for 15 additional minutes. Read the volume of solids immediately in milliliter per liter (ml/l).
(12) "Staff" means the Division.
(13) "Technology-based effluent limitations (or limits)," or "TBELs," means those effluent limits that are based on minimum treatment requirements.
(14) "Waste stabilization pond" (also called a "lagoon" or "oxidation pond") means an excavated or impounded basin designed for long term detention of treated or untreated wastewater and biological treatment to reduce biochemical oxygen demand and suspended solids. The pond may be single-cell or multi-cell. Stabilization ponds are further defined as:
(a) Photosynthetic Pond means a pond that is designed to rely on photosynthetic oxygenation (i.e., oxygen from algae) for any portion of the oxygen needed for waste treatment; this includes oxidation ponds and facultative lagoons. These ponds may have supplemental aeration by mechanical means. With regard to hydraulic flow, photosynthetic ponds are either of the:
(i) flow‑through type, in which the pond is designed to discharge throughout the year; or
(ii) controlled‑discharge type, in which the pond is designed to retain the wastewater without discharge from six months to one year, followed by controlled discharge over a short time interval, typically one to three weeks;
(b) Aerated Pond means a pond that is designed to rely on mechanical or diffused air aeration rather than photosynthetic oxygenation to provide oxygen needed for biological waste treatment. Aerated ponds are either of the:
(i) complete-mix type, in which sufficient energy is imparted to the wastewater to prevent deposition of solids in the pond; or
(ii) partial-mix type, in which only sufficient energy is used to dissolve and mix oxygen in the wastewater. Solid materials that settle in the partial-mix pond are decomposed anaerobically. Algae are commonly found in the partial-mix aerated pond, but the pond's design does not rely on photosynthetic oxygenation.
This definition does not include polishing or holding ponds which are preceded by other biochemical or physical/chemical secondary treatment processes and designed to increase their efficiency.
(15) "Water quality-based effluent limitations (or limits)," or "WQBELs," means those effluent limits that are established to ensure that a discharge does not cause or contribute to a contravention of state surface water quality standards.
(16) "Water quality limited" segment of a surface water means a segment in which water quality does not meet applicable water quality standards or is not expected to meet them even after the application of minimum treatment requirements.
History Note: Authority G.S. 143-215; 143-215.1; 143-215.3(a)(1);
Eff. February 1, 1976;
Amended Eff. August 12, 1979; November 1, 1978; December 1, 1976;
Readopted Eff. May 1, 2020.