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i. Pressure manifold, low-pressure pipe distribution or drip distribution shall be <br /> required for all flow equalization systems. Serial distribution may be used for <br /> retrofitting existing serial distribution systems if the effluent flows through an <br /> orifice control device before the flow becomes gravity(orifice shall be <br /> minimum of 3/4-inch for 1-1/2-inch supply line, 1-inch for 2-inch supply line in <br /> order to achieve minimum 2-fps scour velocities). An accessible turn-up with a <br /> threaded cap and regulating valve shall be provided prior to the orifice control <br /> device to allow regulation of the flow (note: do not adjust flow to be less than <br /> necessary to achieve 2-fps scour velocity). <br /> j. Floats: The following floats shall be provided and shall meet the requirements <br /> of Rule .1952 (c)(5) <br /> i. A low- level/redundant-off switch shall prevent the pump from running <br /> in the event the level in the tank is below the pump intake. <br /> ii. A timer-enabling switch shall be set at or above the pump submergence <br /> level and shall not allow for partial doses. <br /> iii. A high-level alarm shall activate after the equalization volume is <br /> exceeded. If there is a controlled delay before alarm activation, the delay <br /> shall be no more than 5 minutes. After being silenced, the alarm horn shall <br /> automatically reset and shall be audible with each high level event. The <br /> alarm event counter shall record each activation of the alarm. <br /> iv. A timer override switch located at or above the alarm shall dose no more <br /> than a designed dose event to the drainfield. The alarm shall re-activate at <br /> each override event. The timer override float may be integral with the <br /> alarm float. <br /> Other sensor devices may be utilized as approved by the State but must meet all <br /> four float actions. <br /> k. Dosing Volume: The dosing volume shall be calculated based on the size of the <br /> nitrification fields and the number and frequency of the dosing events desired <br /> per day. The minimum and maximum pump run times shall be in accordance <br /> with pump manufacturer's recommendations. The dosing volume shall be <br /> calculated based on 40 to 80 percent of the drainline pipe volume for <br /> conventional systems and 5 to 8 times the lateral volume for low-pressure pipe <br /> or drip systems. <br /> 1. Drain field: The equalized daily flow(EQ) shall be calculated by adding the <br /> design daily flow for each event as determined by Rule .1949 in the flow <br /> equalization cycle and then dividing by the number of days in the cycle. Under <br /> this approval, the maximum number of equalization days is 14 unless otherwise <br /> approved by the State on a case by case basis. The nitrification field shall be <br /> sized by dividing the equalized daily flow(EQ) by the LTAR as determined in <br /> .1955, .1956 and 1957. <br /> 5 <br /> 105 <br />