Abstract: A closed-environment wet-abrasive blasting system includes a vacuum device for recovering a waste stream of water, abrasive particulate and surface debris. The waste stream is filtered resulting in cleaned water recycling through the system. During operation, water is pumped from a water holding tank to a blast head. Also, abrasive particulate is forced from canister to the blast head. The abrasive material and water form a blast stream which impacts on a surface to treat the surface. The blast head is held to the surface during use by the suction force and defines a work volume over the surface under treatment. In effect, the blast head defines a closed environment in which abrasive particulate water and surface debris do not escape into the surrounding environment, but instead is captured. The vacuum force pulls the surface debris, abrasive particulate and water (i.e., waste stream) from the blast head along a vacuum hose into a recovery tank.