How mud and water removed from ship chain locker ?

The chain moves through the chain pipe and the hawse pipe as the anchor is raised or lowered. The chain pipe connects the chain locker to the deck and the hawse pipe runs from the deck through the hull of the ship. When recovering the anchor, the anchor and chain are washed off with a fire hose to remove mud, marine organisms, and other debris picked up during anchoring. Seawater from the fire hose is directed either through the hawse pipe or directly over the side onto the chain while recovering the anchor. 
The top of the chain pipe has a canvas sleeve to keep water from entering the chain locker through the chain pipe. Under rare circumstances, like heavy weather, rain or green water (seawater that comes over the bow during heavy weather) gets under the chain pipe canvas cover and into the chain locker. A diagram of a typical chain locker is provided in Figure 2. 
Any fluid that accumulates in the chain locker sump is removed by either drainage eductor for discharge directly overboard or by draining the chain locker effluent into the bilge. 
As the fluid in the chain locker sump is being drained for overboard discharge, the locker is sprayed with firemain water to flush out sediment, mud, or silt. An eductor is a pumping device that uses a high velocity jet of seawater from the firemain system to create a suction to remove the accumulated liquids and solids.