COMPLIANCE INFO_1999-2001 - Laserfiche WebLink

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5.1.1.5. Erect barricades, etc., to prevent unauthorized vehicle or pedestrian traffic. 5.1.1.6. Inspect, a minimum of once a day, the excavation and surrounding area. 5.1.2. For additional information on excavation, trenching and shoring safety practices, consult OSHNs "Construction Industry Standards," Part 1926, Subpart P; and "Fall Protection Rules and Regulations." 5.1.3. The minimum depth of the excavation is normally determined by the presence or absence of groundwater and the presence or absence of traffic at the site. These dimensions are critical to the successful installation of a tank and are often regulated by code. 5.1.4. For additional requirements and specifications, refer to federal, state and local codes; NFPA 30, 30A and 31; API RP 1615; PEI RP 100; and FIGURE 5-1 and FIGURE 5-2. 5.1.5. In all cases, the depths of cover given in 5.1.5.1. and in 5.1.5.2. are minimums. 5.1.5.1. Tanks subjected to traffic loads (H-20 loads) must have a cover depth of at least 18 inches of backfill [36 inches for 12 -foot tanks] plus 6 inches of reinforced concrete or 9 inches of asphalt. (See FIGURE 5-1.) In a wet condition, sufficient overburden and/or an appropriate anchoring system must be 40 present to offset buoyancy of the tank. FIGURE 5-1 5.1.5.2. Tanks not subjected to traffic loads must have a cover depth of at least 24 inches of backfill [48 inches for 12 -foot tanks], or 12 inches of backfill [36 inches for 12 -foot tanks] plus 4 inches of reinforced concrete or 6 inches of asphalt. (See FIGURE 5-2.) In a wet condition, sufficient overburden and/or an appropriate anchoring system must be present to offset buoyancy of the tank. 10 FIGURE 5-2 In a nontraffic installation, ensure that the areas above the tanks are not subjected to traffic or other types of loads, which could cause tank damage and result in death, serious personal injury or property damage. 5.1.5.3. The maximum burial depth is 7 feet of cover over the top of the tank. Deviation from this may be permissible with prior written authorization from Xerxes. Call your Xerxes representa- tive for a special quotation prior to tank purchase if the burial depth is to be greater than 7 feet. 5.1.5.4. Asphalt and concrete pads must extend a minimum of 12 inches beyond the tank in all directions. 5.1.5.5. An unattached manway riser (if present) must not transmit load from the concrete slab to the tank. A minimum space of 6 inches must exist between the bottom of the riser and the top of the tank. 5.1.5.6. Traffic loads from the top slab must not be transmitted to an attached sump or riser. A minimum space of 3 inches must exist between the riser or sump and the slab. 5.2.1. GENERAL 5.2.1.1. The following are minimum spacings and must be increased as needed to accommodate deadmen or anchor slabs. (See Section 6.) 5.2.1.2. Always provide sufficient clearance to allow the deadmen to be set outside of the tank "shadow" (See FIGURE 5-3.)