Weathered and fractured rock should be divided into soil-like weathered material, permeable fractured zones and competent rock. The required support-fluid function changes as the excavation moves through those states.

Weathered rock

Expect mixed particle sizes, fines and occasional clay seams. Density and sand trends help identify whether the main problem is coarse spoil or fine solids.

Fractures

Open fractures can create whole-fluid loss. If fluid properties are already qualified and loss remains high, chemical escalation may not be the answer; casing, grouting or another support measure can be required.

Competent rock and sockets

In competent rock, tooling, cuttings removal and socket cleanliness become more important than increasing support-fluid chemistry. MUDOZAN should only be considered for a genuine carrying-capacity deficit, not as a substitute for cuttings removal.

Final base

A clean socket/base must be verified separately from clean slurry. Stable excavation does not prove the toe is free of sediment.