1. Formation constructed to engineers specification to provide a smooth void free surface onto which the RAWMAT® HDB is laid.
2. Rolls of RAWMAT® HDB are simply pulled of the roll and laid directly onto the formation, there is no requirements for protection geotextiles.
3. Rolls are overlapped by following the 150mm lap lines printed on the rolls.
4. RAWMAT® HDB is laid and overlapped to cover the entire tank base running up and over the berm to allow for connection to the bund floor lining membrane.
5. Rolls of RAWMAT® HDB are simple to joint, this is done by peeling back the white geotextile of the lower sheet and applying Rawpaste Mastic to the black geotextile side of the upper sheet.
6. Sealing to tell-tale pipes is done by making a star cut into the roll, feeding the tell-tale pipe through and applying RAWSEAL® waterstop and Rawpaste Mastic to seal.
7. Once sealed through the main sheet, apply an additional patch sealed with Rawpaste mastic before replacing the white geotextile.
8. When the formation has been covered with RAWMAT® HDB, the overlaps and tell-tales sealed the confining material is placed and compacted to the engineers specified requirements.
9. Once backfill has been placed and compacted the bitsand layer is placed prior to the placement of the tank.
10. The tank is then placed on the berm, the RAWMAT® HDB offers secondary containment protection to the ground.