Abstract: At 1:00 p.m. on March 14, 2013, Employee #1 and Employee #2, of Los Angeles Engineering Inc., a general engineering and pipeline construction company, were working on a pipeline construction project. They were excavating a trench for the purpose of installing steel reinforced concrete pipe for a storm drain. They were in a section of the trench that lacked any shoring or other protection and checking the depth. The trench measured 14 feet deep. Coworker #1 was operating a backhoe in the trench, excavating soil from a trench cave-in that had occurred along the south wall two hours earlier. Coworker #2, the supervisor, was in the immediate area of the earlier collapse, operating a front loader atop the north wall of the trench at surface grade level. The north wall of the trench collapsed. It collapsed directly on Employee #1, pushing him into the south wall of the trench and completely burying him. Employee #1 was killed. The collapsing trench pushed Employee #2 against a trench shield in a shored section of the trench, burying him to his thighs. Emergency personnel were called, and at 1:45 p.m. the Los Angeles Fire Department dispatched fire and rescue resources to the site. At 1:55 p.m., the Los Angeles Fire Department notified Cal/OSHA. Fire Department personnel exposed Employee #1's head and determined that he was dead. They began a recovery operation that lasted 7 hours. Employee#2 was extricated from the trench and transported by air ambulance to UCLA Ronald Reagan Medical Center, where he was hospitalized and treated for trauma to his legs, including one or more leg fractures. Cal/OSHA, which immediately responded after being notified by the Los Angeles Fire Department, arrived at the site at 3:00 p.m. Cal/OSHA contacted the employer, fulfilling reporting requirements. Cal/OSHA's investigation determined that Employees #1 and #2 were working in a 14-foot deep trench that was not protected from a cave-in by any protective systems or procedures. The trench in which they were working had caved in two hours earlier. When the second cave-in occurred, killing Employee #1 and seriously injuring Employee #1, their supervisor was in the immediate area and was in possession of engineering documents indicating that employees must not work in the unprotected sections of the trench. ACCIDENT RELATED-SERIOUS CITATIONS ISSUED: Cal/OSHA planned to issue a Willful Serious Accident Related citation for a violation of T8 CCR 1541.1(a), a serious citation for a violation of 1541(k), and a serious citation for a violation of 1509(a).