Each job is different and requires a specific procedure. Some tanks may require entry in order to clean them properly. It may not be feasible or possible to enter some vessels. In these instances, a robotic 2-D or a 3-D nozzle may be used. Water flow, spin rate, and drop rate are regulated so that all areas of the tank are hydro-blasted and cleaned without ever entering the tank. The Hydro-mower is another tool that cleans more efficiently that conventional methods. The "mower" utilizes the high pressure supplied by the hydro-blaster to direct water flow to spinning nozzles. The water is focused on the concrete or steel pad and the full potential of the cleaning power is realized with minimal waste. Other specialty nozzles, such as high water flow or rotary action, are available if needed.