Current through Register Vol. XLI, No. 40, October 4, 2024
Section 47-30-7 - Calculating WV/NPDES Conditions7.1. Outlets and Discharge Points. All permit effluent limitations, standards, and prohibitions shall be established for each outlet or discharge point of the permitted facility, except as otherwise provided under paragraph 6.3.k.2. and subsection 7.8. of this rule. Where a person has a number of outlets emerging into the waters of this State in close proximity to one another, such outlets may be treated as a unit for the purposes of section 7 of this rule.7.2. Metals. All permit effluent limitations, standards or prohibitions for a metal shall be expressed in terms of the "total recoverable metal" as defined in 40 C.F.R. Part 136 unless: 7.2.a. An applicable effluent standard or limitation has been promulgated under the CWA and specifies the limitation for the metal in the dissolved or valent form;7.2.b. In establishing permit limitations on a case-by-case basis, it is necessary to express the limitation on the metal in the dissolved or valent form in order to carry out the provisions of the CWA; or7.2.c. All approved analytical methods for the metal inherently measures its dissolved form.7.3. Continuous Discharges. For all continuous discharges, all permit effluent limitations, standards, and prohibitions, including those necessary to achieve water quality standards, shall be stated as maximum daily and average monthly discharge limitations.7.4. Noncontinuous Discharges. Discharges that are not continuous shall be particularly described and limited, considering the following factors, as appropriate: 7.4.c. Maximum rate of discharge of pollutants during the discharge; and7.4.d. Prohibition or limitation of specified pollutants by mass, concentration or other appropriate measure.7.5. Mass Limitations. Any pollutants limited in terms of mass additionally may be limited in terms of other units of measurement, and the permit shall require the permittee to comply with both limitations.7.6. Pollutants in Intake Water. Except as provided in subsection 7.7. of this rule, effluent limitations imposed in permits shall not be adjusted for pollutants in the intake water.7.7. Net Limitations.7.7.a. Upon request of the discharger, technology-based effluent limitations or standards shall be adjusted to reflect credit for pollutants in the discharger's intake water if: 7.7.a.1. The applicable effluent limitations and standards contained in 40 C.F.R. Subchapter N specifically provide that they shall be applied on a net basis; or7.7.a.2. The discharger demonstrates that the control system it proposes or uses to meet applicable technology-based limitations and standards would, if properly installed and operated, meet the limitations and standards in the absence of pollutants in the intake waters.7.7.b. Credit for generic pollutants such as biochemical oxygen demand or total suspended solids should not be granted unless the permittee demonstrates that the constituents of the generic measure in the effluent are substantially similar to the constituents of the generic measure in the intake water or unless appropriate additional limits are placed on process water pollutants either at the outfall or elsewhere.7.7.c. Credit shall be granted only to the extent necessary to meet the applicable limitation or standard, up to a maximum value equal to the influent value. Additional monitoring may be necessary to determine eligibility for credits and compliance with permit limits.7.7.d. Credit shall be granted only if the discharger demonstrates that the intake water is drawn from the same body of water into which the discharge is made. The Secretary may waive this requirement if he or she finds that no environmental degradation will result.7.7.e. The provisions of subsection 7.7. of this rule do not apply to the discharge of raw water clarifier sludge generated from the treatment of intake water.7.8. Internal Waste Streams. 7.8.a. When permit effluent limitations or standards imposed at the point of discharge are impractical or unfeasible, effluent limitations or standards for discharges of pollutants may be imposed on internal waste streams before mixing with other waste streams or cooling water streams. In those instances the monitoring requirements under subsection 5.11. of this rule shall also be applied to the internal waste streams.7.8.b. Limits on internal waste streams will be imposed only when the fact sheet under section 11 of this rule sets forth the exceptional circumstances that make such limitations necessary, such as when the final discharge point is inaccessible (for example, a point that is beneath ten (10) meters of water), the wastes at the point of discharge are so diluted as to make monitoring impractical, or the interferences among pollutants at the point of discharge would make detection or analysis impracticable.7.9. Disposal of Pollutants into Wells or Underground Mines or by Land Application. 7.9.a. Calculations of Effluent Limitations (General). When part of a discharger's process wastewater is not being discharged into surface waters of the State because it is disposed into a well, underground mine or by land application thereby reducing the flow or level of pollutants being discharged into surface waters of the State, the Secretary may establish limits on the concentration and quantity of such discharge and applicable effluent standards and the limitations for the surface discharge in a WV/NPDES permit shall be adjusted to reflect the reduced raw waste resulting from such disposal.7.9.b. Calculations of Effluent Limitations (Specified). The provisions of subdivision 7.9.a. of this rule shall not apply to the extent that promulgated effluent limitations guidelines specify a different specific technique for adjusting effluent limitations to account for well injection underground, mine disposal or land application.7.9.c. The provisions of subdivision 7.9.a. of this rule do not alter a discharger's obligation to meet any more stringent requirements established under sections 5 or 6 of this rule.