Abstract: At 12:24 p.m. on August 15, 1985, Employee #1 was inside a manhole box helping to guide a section of sewer manhole into place. As a backhoe lowered the manhole section, Employee #1 saw that the chain reaching from the backhoe bucket to the manhole was too short. He signaled the operator to withdraw the section and adjust the length of the chain. While the manhole section was being withdrawn, Employee #1 stepped outside the protective box into an unprotected part of the trench. The north side of the trench collapsed above him, knocking him down, partially covering him, and pushing him part way back into the manhole box. Employee #1 was hospitalized for a fractured pelvis along with numerous lacerations, abrasions, and contusions. The manhole excavation and adjacent trench were approximately 15 ft deep, with vertical sides.