MarineFAST® Wastewater Treatment Systems are commonly referred to as a Type II (two) MSD biological (aerobic digestion) treatment system. The Type II MSD systems are powerful, flow-through discharge devices tested in conditions described in 33 CFR 159.121. MarineFAST® Marine Sewage Treatment Marine and offshore sewage treatment systems built to handle extreme environments. All MarineFAST® (Fixed Activated Sludge Treatment) units are fully certified by US Coast Guard under U.S. and IMO regulations.