Inspection Detail

Inspection: 300813003 - Greka Energy

Inspection Information - Office: Labor Enforcement Task Force (Letf) Unit - South

Investigation Summary

At approximately 11:12 a.m. on April 18, 2002, three workers were replacing a leaking 2-inch casing gate valve. At the wellhead, there were about 25 vehicles that were parked near the well. The vehicles belonged to harvest workers that were conducting strawberry harvesting northeast of the wellhead. One vehicle was parked at the wellhead and the others were parked along a windscreen fence that was 15 feet to 20 feet southeast of the wellhead. One of the workers backed a vacuum truck up to the wellhead and connected a 3-inch bleed down line to the casing gate valve to relieve gas pressure (blowdown) in the wellhead. The process vents the gas through the truck, removing any hydrogen sulfide that may have been present, and discharges it through a bleeder valve. The blowdown operation lasted approximately one hour, at which point the farm laborers began exiting the field towards their vehicles. One of the workers closed a 2-inch casing gate valve but did not close the bleeder valve on the bottom of the truck. Therefore, the gas stream continued to be vented from the bottom of the truck. The laborers started their cars and left the area, with the exception of one car that was north of the wellhead and had two occupants inside. Employee #2 was the driver of the vehicle and was not too familiar or comfortable with its controls. Due to the car's close proximity to the well, one of the workers instructed Employees #1 and #2, in both English and Spanish, not to drive forward into the gas cloud. Employee #2 expressed that she did not know how to operate the vehicle in reverse and Employee #1 switched seats with her. Employee #1 needed to move the car forward in order to maneuver around a vehicle parked behind him. The vehicle entered the gas cloud and an explosion occurred. One of the workers immediately shut the bleeder valve at the bottom of the truck and emergency services were contacted. A crew of firefighter paramedics responded within 10 minutes. Both Employees #1 and #2 were hospitalized at Marian Medical Center and treated. Employee #1 suffered minor injuries, while Employee #2 experienced second-degree burns to her face and arms. She later died. During an investigation, it was determined that the gas stream was not tested for the Lower Explosive Limit or hydrogen sulfide prior to the blowdown operation, but air monitoring was conducted at the beginning of the operation with no hydrogen sulfide detected. Additionally, there were 30 barrels of water on the vacuum truck.

Keywords: BURN, WELL, GAS, EXPLOSION, PRESSURE PIPING, WELLHEAD, ARM, FACE, PRESSURE RELEASE