Had a similar project near a pumping station that required the lagging to stay in place. Somewhat expensive but used the sides of trench boxes. They stayed in place and solved that problem. Trench guys will often resell older boxes which work well for the lagging you are looking for.
PS...
I have a complex slope stability design to complete which contains a deep layer of caliche. Lightly cemented. Looking for shear strength parameters for this material to use in the analyses.
Thx in advance.
Durtguy
