I have just excavated my hole for my 20x40 ft pool with an 8 ft deep end. My shallow end floor is ok (not perfect) and the ramp to the deep end hopper is manageable. But my deep end walls are rough due to layers of shale encountered. Although my excavator wasn’t a pool guy” I think he did the best he could with my soil condition. I need to smooth somewhat by hand and the deep end wall corners, but my question is if there are cave ins and roughness due to extruding shale what is the best approach? Is there a stabilization material to use or patch those areas with pool base first ?