As a mud engineer, also known as a drilling fluids engineer or mud man, you manage the drilling fluid used in the digging of oil wells. This involves making adjustments to the liquid being used, supervising the equipment on a rig, and helping test for oil and gas. This position offers a significant amount of control over the specifications of a drilling plan, in part because the fluid mixture must be customized to create the most effective drilling path through the unique terrain of the area. Since your presence is required during the drilling process, mud engineers spend almost all of their time on-site.