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Use of flow equalization in systems that have a design flow exceeding 3000 gallons <br /> per day or when the criteria of this innovative approval are proposed not to be <br /> followed may be considered for review and approval by the State on a case-by-case <br /> basis, prior to permitting by the local health department. <br /> II. Flow Equalization Terms: <br /> a. Equalized Daily Flow(EQ) - The total volume of wastewater generated by flow <br /> events at the facility during the flow equalization cycle divided by the number <br /> of days in the cycle. <br /> b. Flow Equalization Cycle—The time period in which wastewater will be stored <br /> and dosed. Ex. 7day cycle, 14 day cycle, etc. <br /> c. Flow Event—An event in the flow equalization cycle in which wastewater will <br /> be generated. Ex/church service, sporting event, day of operation, etc. <br /> d. Orifice Control Device—A calibrated flow restriction placed in the supply line <br /> prior to the nitrification field that allows the flow to be controlled. <br /> e. Flow Balance—A daily account of the amount of stored effluent in the <br /> equalization tank which is derived from the incoming flow, residual storage, and <br /> the outgoing flow. The flow balance shows the day of the week, the amount of <br /> wastewater generated, the amount of wastewater dosed, and the residual amount <br /> of effluent left in the dosing tank each day. At the end of the flow equalization <br /> cycle, the sum of the incoming flow should equal the sum of the amount dosed. <br /> III. System Description: <br /> a. Minimum pretreatment by septic tank and effluent filter as required in 15A <br /> NCAC 18A .1952. <br /> b. Grease Trap as required in 15A NCAC 18A .1955(k) <br /> c. Equalization/Pump Tank <br /> d. Timer Control Panel <br /> e. Pump <br /> f. Pressure Manifold, LPP distribution system, other pressure dispersal devices, or <br /> an Orifice Control Device when serial distribution is utilized <br /> g. Nitrification Field <br /> IV. Siting Criteria: <br /> The Flow Equalization System with timed dosing may be utilized on sites that meet <br /> the following criteria. <br /> a. Sites classified suitable or provisionally suitable in accordance with rules .1939 <br /> .1948; <br /> b. Sites reclassified provisionally suitable in accordance with Rule .1956; <br /> c. Sites meeting the criteria for low pressure pipe systems in accordance with Rule <br /> .1957(a)(2); or <br /> 2 <br /> 102 <br />