COMPLIANCE INFO_2005-2010 - Laserfiche WebLink

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Trenching,bedding Recommended practices and backfilling Although fiberglass pipe has excellent strength,it must be protected against impact which may occur from improper handling or during backfilling. • Provide a trench width equal to the pipe diameter plus six inches on each side. Separate multiple lines by at least 4 inches.Refer to Fig.5-1. • Provide a minimum of 18 inches of select backfill between the top of the pipe and unpaved ground surfaces. • Provide a minimum of 4 inches of select backfill between the top of the pipe and reinforced concrete pavement(4 inches minimum thickness). • Provide a minimum of 8 inches of select backfill between the top of the pipe and asphalt pavement(2 inches minimum thickness). • Slope the trench bottom evenly from the dispensers back to sumps or tanks at a minimum% in/ft. • Maintain the trench bottom free of hard or sharp objects. • Grade the trench bottom with at least 6 inches of select backfill to provide firm, even support for the pipe.Compact the subgrade well to prevent differential settling. • Protect the pipe from impact during backfilling and abrasion during operation by surrounding it with four to six inches of select backfill such as washed sand,pea gravel(3k-inch maximum)or crushed stone(lb-inch maximum). • Wrap pipe lying near concrete with rubber or foam padding to avoid direct contact with the concrete. Norte--�—� Asphaft '',-, 2(min) 4(min) ` 18(min) 4 • -r- - 8(min) r a ` 4(min) ® CO , • Fig.5.1.Use only select materials _ for bedding and backfilling select back® - 6(mh) Dualoy 30001L fuel handling ' systems.Native materials ® , are rarely suitable and Nathre should not be used. Sol 4( ) 6(min ) Dry fitting contained Recommended practices primary piping Have island forms,boxes,and shear valves in place before dry fitting. • Lay out and dry fit primary and containment piping at the same time. • Allow sufficient clearance when dry fitting the primary to accommodate the containment fittings.Dimensions of containment fittings may be found at the end of this Fig.and During layout,bonding document. _/� and inspection,support the r®®—®—®®®—bond not nm piping on 2x4 blocks to keep the ' Do p' ary system i joints clean and to keep bedding ( I together before the secondary ' out of the pipe.Remove supports I containment system has been before burial � dry fit. I 5