About 2 acres steep natural ravine from glacier retreat in S central IL, Depth at very bottom 40+ ft. Depth planned 25 ft building dam at lowest moving in and up ravine. Only possible due to oil pipeline coming through clearing all trees shrubs, stumps roots etc. getting clay and dirt no problem, large hill just south and cleared is approximately 250,000-300,000 cubic yards. Dam runs E to W about 25 ft high now about 140 ft long. Final detail survey can not be completed till pipeline in and everything regraded etc. dam could most likely be less high. Depth of pond may be able to go to 20 ft deep. Have more photos of area.