Definition - What does Mud Wall mean?
A mud wall is a borehole wall that has been reinforced with a slurry mixture. Bentonite clay is often used in drilling fluid to seal the borehole wall to prevent water seepage. Drilling fluid is commonly referred to as mud or slurry. A mud wall may be used in lieu of more expensive methods to maintain the integrity of the borehole.
Trenchlesspedia explains Mud Wall
The semi-liquid mixture of drilling fluid usually includes a type of clay called bentonite, which can cake the walls of a borehole and mechanically support its structure. It’s all part of a mixing system that delivers, retrieves, and recycles the drilling fluid for re-use.
The science of mud is essential to trenchless construction. Proper mixture and methods are important. Reinforcing a borehole with bentonite mud during the drilling process is one of the techniques that makes horizontal drilling so successful.