BASF seals Clem 7 tunnelBrisbane's Clem 7 tunnel is 4.8 km long with a deepest point 70 m below sea level. To save time on waterproofing, contractor LBB JV selected a spray-applied polymer membrane from BASF Construction Chemicals. The selected MASTERSEAL 345 ensured all irregularities in the porous profile of the tunnel were evenly coated, providing a positive waterproof seal. Read the full press release and visit www.meyco.basf.com. For full construction history visit tunnelbuilder archive au/21. 30/11.