Inspection Detail

Inspection: 304478811 - Petro-Hunt Llc

Inspection Information - Office: Baton Rouge Area Office

Investigation Summary

At approximately 3:00 a.m. on August 18, 2002, Employees #1 through #5 were flowing a well into a frac tank at the site of the Raymos Investment Number 1 Well, approximately 4 miles north of Pierre Part, Louisiana. Drilling had started on this well on February 26, 2002 and was completed on August 14, 2002. The rig was removed and completion work started the following day when the crew had begun to perforate the well. At a depth of approximately 75 feet, the wire line attached to the perforating gun gave out and the gun became hung up in the well head. The employer pumped methanol into the hole to free the perforating gun. The wire line rams cut both the electric and logging lines, causing the tools to fall to the bottom. The employer removed the tools before beginning to test the well, which started on the night of August 17 and continued into the morning of August 18. During the testing, oil and water from the well was flowed into the frac tanks near the well head. The frac tank containing the oil was approximately two-thirds full, meaning the capacity for vapor accumulation was severely reduced. At some point prior to the accident, Employee #5, the well testing contractor, gauged the frac tanks and determined that they were filling faster than expected. At approximately 2:30 a.m., a request was made to Settoon Industries, a local contractor, to have a suction truck come to the site to remove some of the fluids from the frac tanks. At about this same time, Employee #1, the drilling foreman, contacted Employee #2, the production technician, to come to the site to look at the problem. When Employee #2 arrived at the site, he was accompanied by his son, Employee #3. When the suction truck arrived at the site, Employee #4, the driver, was directed to position the truck with the rear of the tanker close to the frac tanks and the tractor angled toward the office trailers. The driver left the truck running and walked to the front of the frac tanks to speak with the other four workers. Employee #4 then turned and began to walk back to his truck when a flash fire ignited around the frac tank that contained the oil. All five employees sustained severe burns and were transported to the Burn Unit at the Baton Rouge General Hospital where they were hospitalized. Approximately 10 days later, Employee #4 died from complications of his injuries. Subsequent investigation into the cause of the fire determined that no one was smoking near the frac tank nor was anyone using a cell phone or two-way radios. The flare was operating at the time, but the 60 foot tall stack was located approximately 160 feet away. Prior to the flash, one witness observed a blue flame propagating near the base of the frac tank. It was hot and humid and, since there was no wind, hydrocarbon vapors were accumulating along the ground near the frac tanks, although the concentration of the vapors was less than the LEL. Because the flame proceeded toward the rear of the frac tank, this suggests that vapors were also escaping from a open hatch at the rear of the tank. The physical evidence indicated that when the fire reached the area of the rear hatch, the flame went vertical and up the side of the tank until the vapor concentration exceeded the LEL. On the inside of the frac tank, the inlet hose opening was flush with the top of the vessel. As oil flowed from the hose into the tank, a static charge developed at the opening since the oil was splash loaded and a "T" deflector or conductive down spout with a 45-degree bevel at the end was not installed near the end of the down spout. The vapor concentration inside the vessel was under the LEL and any static charge would not cause the vapor to explode until it exceeded the LEL. The two sources of hydrocarbons coupled with the perfect weather conditions suggests that it was only a matter of time before an explosion would occur. The origin of the blue flame was not determined. Employees #1 and #3 through #5 all had on cotton clot

Keywords: FLAMMABLE VAPORS, OIL WELL PERFORATING, BURN, CLOTHING, FIRE, STATIC ELECTRICITY, WORK RULES, TRUCK DRIVER, DRILL OPERATOR, CHEMICAL VAPOR