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1/8-inch diameter. Note: small pipe and perforation sizes are preferred to provide the <br /> largest possible scouring velocity in the laterals, minimize hole clogging, and at the <br /> same time provide uniform distribution during frequent small doses. <br /> (4) Pipe perforations shall point upwards,except 1-2 perforations which shall point <br /> downwards to drain the lateral. <br /> (5) Requirements for LPP systems in Rule.1957(a)(5),except as provided for <br /> herein, shall otherwise be met.This includes requirements for lateral turn-ups,turn-up <br /> protective sleeves,and manifold cleanouts. <br /> e. An observation port(minimum 6-inch diameter)or similar device with a <br /> removable cap shall be provided to facilitate easy above-grade observation of a <br /> portion of the sand filter surface. <br /> f. An effluent sampling point must be established,such as follows: <br /> (1) Locate a sampling access port in the discharge pipe between the underdrain exit point <br /> from the sand filter and the drainfield. A 4-way cross or similar device can be used <br /> where the underdrain discharge pipe and the vertical sampling port intersect to facilitate <br /> collection of effluent samples. The vertical sampling access port/vent pipe must come <br /> above the ground surface,be constructed of 4-inch diameter Schedule 44 PVC pipe,be <br /> vented to the atmosphere,and contain a removable cap to allow visual observation and <br /> sampling of sand filter effluent flowing to the drainfield. The cap shall be removable <br /> and constructed to prevent the entrance of rainwater,surface water,rodents and insects. <br /> This could also simultaneously meet the filter underdrainage system requirement. <br /> (2) Alternately, if ventilation is otherwise provided for the filter underdrainage system(see <br /> above), a distribution box or drop box may be used for the sampling access point, <br /> located in the final effluent discharge line prior to the drainfield trenches. The box must <br /> be constructed to facilitate at-grade access. <br /> g. Dosing system <br /> (1) A State-approved pump tank shall be provided with a liquid capacity at least <br /> equal to the required Septic tank liquid capacity. <br /> (2) Small,frequent doses shall be used to provide maximum treatment of the <br /> effluent. Minimum dose volume shall be 5 tunes the liquid capacity of the distribution <br /> laterals,plus the volume of any manifold and supply line sections which drain between <br /> doses. <br /> (3) Timed dosing regimes rather than on-demand dosing shall be utilized with dosing <br /> frequencies ranging from 4 to 24 doses per day for Type A and B sand filters,and 24 to <br /> 48 doses per day for Type C sand filters(see below). <br /> (4) The pump shall be controlled using a control panel that includes an adjustable two-stage <br /> timer(to control and adjust number of doses per day and dosing time),an elapsed run <br /> time meter,and a pump impulse counter. <br /> (5) The systems shall be designed for a minimum distal pressure head of 4 feet. <br /> (6) Requirements for pump dosing systems in Rule.1952(c),except as provided for <br /> herein,shall otherwise be met. <br /> 7 <br /> 133 <br />