Abstract: At approximately 9:00 a.m. on November 2, 2012, Employee #1, the owner of a heavy equipment company, was working for Creative Home Interiors, Inc., dba Chi Construction. Chi Construction had been hired by Plumas County, CA to rebuild a boat launch at Honkers Bay Dock, Lake Davis, in Portola, CA. Employee #1, who had been hired as the main equipment operator for the project, was operating a Komatsu PC 290 hydraulic excavator rented by Chi Construction and excavating mud from the lake. Employee #1's brother, Coworker #1, a regular employee of Chi Construction, also was working at the site, operating a backhoe loader and assisting Employee #1. However, Coworker #1 was away from the excavation site, driving the backhoe to a parking lot approximately .25 mile away to dump a load of mud and then returning. During this time, the excavator, with Employee #1 in the operator's cab, apparently tipped over and sank into the lake. Employee #1 drowned. According to Coworker #1, who was interviewed during the investigation, he and Employee #1 had performed all their pre-shift inspections on the equipment, and both machines were in good working condition. The employer provided an IIPP and Code of Safe Practices meeting minimum requirements. Both Employee #1 and Coworker #1 were experienced operators.