Outside installations must be a minimum of 50mm above ground level to exclude stormwater.
Chequerplate covers can be fitted with recessed drop handles and/or frame to suit brick paved areas.
Cast iron covers can be supplied.
Epoxy coating is available upon request.
Increments are available on request.
Heavy duty and light duty concrete covers with cast in cast iron covers and frames are available.
Trade waste arresters are available as either oil and grease arresters, settling pits or acid neutraliser pits.
Excavation, Base Preparation and Backfill
Over excavate by 300mm all around to all sides for backfill.
Base preparation shall consist of excavating flat uniform surface to a depth of 100mm below the required level and backfilling with 10-12mm gravel for bedding of the tank.
Where natural ground is extremely soft, over excavate by 200mm, compact 100mm of 50-75mm ballast into the surface and backfill to the required level with 10-12mm gravel.
Complete backfilling with approved granular material such as sand compacted in 150mm layers to 90% maximum dry density in accordance with AS3798.
After installation of the tank, backfilling shall be raised evenly around the tank with a maximum backfill height differential of 400mm at any time.
Please Note: Where circular gas-tight inspection covers are fitted a minimum of 600mm vertical clearance between the underside of the cover slab and the static water level in the arrester is necessary to facilitate routine servicing.