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<br />Page 10 Session Law 2024-44 Senate Bill 802 <br />water is estimated to be low flow or zero flow, or under certain conditions non-existent, as <br />determined by the United States Geological Survey (USGS). Within 20 days of the date USEPA <br />approves the draft rules submitted pursuant to this subsection, the Commission shall initiate the <br />process for temporary and permanent rules pursuant to Chapter 150B of the General Statutes. <br />The draft rules submitted to USEPA for approval shall include all of the following: <br />(1) Defined terms. – <br />a. "Treated domestic wastewater" shall mean sewage and wastewater <br />comprised of waste and wastewater from household, commercial or <br />light industrial operations (e.g., homes, restaurants, car washes, <br />laundromats servicing only domestic laundry) excluding any industrial <br />process wastewater regulated by USEPA under the Categorical <br />Pretreatment Standards. <br />b. "Low-risk discharges" means discharges of 2 million gallons per day <br />or less of treated domestic wastewater when the dissolved oxygen <br />content (DO) of the effluent is significantly higher (1.5 mg/l or greater) <br />than the DO of the receiving water during low flow periods and the <br />biological oxygen demand content (BOD) of the effluent is <br />significantly lower (1.5 mg/l or more) than the DO of the effluent. <br />c. "Sag" means a reduction in the existing DO in the background surface <br />receiving water to which treated wastewater will be discharged. Sag is <br />typically related to nutrient elements within treated wastewater, which <br />may promote the growth of oxygen-consuming micro-organisms, <br />increasing the BOD, which at elevated levels may reduce DO in the <br />background surface water body. <br />(2) Criteria for permitting. – <br />a. Applicants shall be required to demonstrate, through an analysis <br />comparing the limits of the NPDES permit to the characteristics of the <br />receiving water, that a proposed discharge meets criteria for a low-risk <br />discharge as defined in this subsection. When a discharge is <br />determined to be low-risk, the applicant shall demonstrate using <br />simple modeling of the applicant's choosing, provided that the model <br />chosen is utilized elsewhere in USEPA Region 4, such as the <br />Streeter-Phelps model used in the State of Alabama, to show that the <br />Sag, if any, in the DO of the receiving water will not exceed 0.1mg/l. <br />b. Discharges to low flow or zero flow receiving waters shall be subject <br />to the following conditions: <br />1. The receiving waters fall within any of the following <br />categories: <br />I. The 7Q10 or 32Q2 flow statistics are estimated to be <br />zero by the USGS. <br />II. The drainage area of the discharge point is less than 5 <br />square miles as specified by the USGS on-line tools or <br />other methodology that meets the standard of care for <br />such work. <br />III. The 7Q10 flow is estimated to be less than 1 cubic foot <br />per second by the USGS. <br />2. The proposed flow for any wastewater discharge shall be the <br />lesser of the following: <br />I. No more than one-tenth of the flow generated by the <br />one-year, 24-hour storm event given the drainage area <br />and calculated using the rational method. The rational <br />14