Abstract: On October 22, 2012, Employee #1, of S.M. Hentges & Sons Inc., was operating a backhoe excavator, dredging vegetation and sedimentation from a pond used to collect runoff from an airport. The pond covered approximately 4 acres. It was 30 ft. to 40 ft. deep. The pond's top 2 ft. was water, and the remaining depth consisted of cattail bog and decomposing vegetation. Employee #1 was operating the backhoe on top of wood mats used to support the backhoe and prevent it from sinking into the pond. He was keeping three mats underneath the backhoe and moving one mat in front as he moved forward. The mat farthest to the rear rolled, causing the backhoe to begin sliding into the water. Employee #1 attempted to rotate the backhoe cab to stop the machine from sliding. He was found crushed to death, pinned between the top of the cab and the mat. Minnesota OSHA investigated and proposed two serious citations.