COMPLIANCE INFO_1995-1999 - Laserfiche WebLink

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I \ WARNING: In a non -traffic installation, insure that the areas above the tanks will never be subject to traffic or other type loads. NOTE: +hese depths of cover are MINIMUMS in all cases. NOTE: Asphalt and concrete pads must extend a minimum of 12 inches beyond tank in all directions. NOTE: Maximum burial depth is 7 feet of cover over top of tanks. NOTE: Unattached manway riser (if present) must not transmit load from the concrete slab to the tank. There must be a minimum of o inert soace between the bottom of the riser and the top of the tank. NOTE: Tanks of 10 foot diameter and 30.000 gallons and larger may require a deeoer burial or thicker top slab to offset buoyancy. Contact Xerxes' Tecnnical Service Department for further information. C NOTE: These are minimum spacings and must be increased as needed to accommodate deadmen or anchor stabs. Refer to Section 7 on tank anchoring. Always allow sufficient clearance to allow the deadmen to be set outside of the tank shadow. TOP VIEW 1411`21:Y111 0 • Where shoring is not required to maintain a vertical wall from top to bottom of the excavation, and the soil is stable, the minimum spacing between the sidewall or endcap of the tank and side of excavation must be 18 inches (24 inches for 12 foot tanks]. If more than one tank is to be installed in the same hole. there must be at least 18 inches between the tanks. rr'7•T1'If If the soil has less than '50 IbsJso. ft. cohesion as calculated from an unconfined compression test; or in soils having an ultimate beating capacity of less than 3500 lbsisq. ft.. or where soil ,mil not maintain a vertical wail, the excavation must allow a minimum space equal to 1l2 the diameter of the tank between the side amenocao of the rank and the excavation wall to ennance lateral soil resistance. The spacing between adjacent tanks, 18 inches. emains the same. A reinforced concrete siab may oe required under :he :ank for the foundation in rile pit oottom. lla :•ARMNG: if the soil is extremely soft or inherently unstable, (e.g. peat, quicksand, muck, landfill, very soft or highly expansive clay, etc.) Xerxes recommends that the tank owner seek the advice of a local foundation professional engineer. FiLTER FABRIC The tank owner or his technical representative is responsible for determining whether after fabric or an alternate filtering technique is appropriate for a specific installation. Filter fabric allows the passage of water but prevents the migration and mixing of native soil and the select backfill material. It helps preserve the integrity of the select backfill envelope which surrounds and supports the tank. Xerxes recommends that filter fabric be used when the tank may be installed in: • areas with frequently changing ground water conditions or areas subject to tidal fluctuations, • unstable soils such as cited above, • water conditions with silty soil. For further information concerning fabric specifications and installation procedures, consult the filter fabric supplier's installation guide or instructions. To install filter fabric, typically filter fabric manufacturers recommend that the installer line the excavation sides and bottom with the fabric. Overlap adjoining panels by at least 12 inches. Place backfill material on the panels around the edge of the hole to anchor them in place. in wet -hole conditions, use backfill material to sink and hold the fabric in place on the hole bottom. NOTE: Polyethylene film is not considered an effective mamial to prevent ) migration of pea gravel, crushed stone and native soli; it may tear or degrade while in service. AN CAUTION: Xerxes ifammmends dist every site be thoroughly evaluated for the potential to trap water or otherwise subject the tank to a rise in the local water table. Xerxes recommends that all tanks be anchored in installations in which water my enter the hole. Failure to anchor the tank in a wet hole may damage the tank or surrounding pro Prepare a smooth level bed, 12 inches thicbc, of approved backfill material. Place the tank or tanks onto the bed. Do not set Xerxes tanks directly onto a concrete slab or on timbers, cradles or directly onto the hole bottom. Leveling: As the tank is being placed, set the tank pitch as shown on the site pians. Xerxes does not require that a tank be pitched. All pitch is determined by the tank owners specification. if a double wail tank is pitched, the monitor should be at the tow end. Use the Loos of the ribs to establish ionglitudinal level. Establish lateral level by placing the level across the top of a fitting, a manway or a collar. When the tank is olaced. false the first diameter reading (Der1ecaon rearing W on the cnecxlist). See Section 13 for Instructions on taking deflection readings. if the tank is m oe anchored, instaii the anchoring hardware ral this ime,'See Section 7.