WITSML - Operations Mud Losses Component Schema Volume of mud lost at shakers (at surface). Volume of mud lost in mud cleaning equipment (at surface). Volume of mud lost in pit room (at surface). Volume of mud lost while tripping (at surface). Surface volume lost other location. Total volume of mud lost at surface. Mud volume lost downhole while circulating. Mud volume lost downhole while running casing. Mud volume lost downhole while cementing. Mud volume lost downhole behind casing. Mud volume lost downhole during abandonment. Mud volume lost downhole from other location. Total volume of mud lost downhole.