CSB investigators determined that a lit cigarette or lighter was the likely ignition source for explosion.
|The site of the fire and explosion lacked warning signs
A fiery explosion that took the life of a 21-year-old member of the public in Weeletka, Oklahoma, on April 14 occurred at an unattended oil and gas production site that was unsecured and likely lacked fire or explosion warning signs, CSB investigators have determined following a four-day field assessment. Investigators arrived in Weleetka on Sunday evening and have been examining the site, conducting witness interviews, and gathering other information throughout the week.
The accident occurred at approximately 9:00 p.m., while six individuals aged 18 to 32 were socializing at the rural site, which was normally unmanned. The site, which had four petroleum storage tanks and two brine storage tanks, was operated on private land by two production firms, Three MG Family Inc. and Enterprise Energy, who leased the mineral rights. A third company, Scissor Tail Energy, operated a gas metering and collection system connected to the production equipment.
The blast occurred about 10 minutes after the group arrived at the site. Witnesses stated that they were drawn to the site when they saw the open gate while driving along a public roadway. Witnesses further stated that oil sites were a common gathering place for local residents and that they were largely unfamiliar with the hazards.
Based on witness interviews, CSB investigators determined that a lit cigarette or lighter was the likely ignition source for the explosion, which happened as the 21-year-old male who later died, was peering into the hatch on top of one of the tanks. That tank contained what was later described as approximately 160 barrels of light crude oil. The resulting explosion and fire engulfed the victim and caused a second explosion in an interconnected tank. The victim suffered third-degree burns over 85% of his body. He was able to describe the accident to emergency response and ambulance personnel, but died the following morning at a Tulsa burn unit. Another individual suffered second-degree burns. A fire burned for more than three hours at the site until it could be extinguished by several responding fire departments using foam.
'No Place to Hang Out' video educates about fire risks and hazards at oil sites
"The catwalk leading to the top of the tank was unsecured and readily accessible," said CSB Investigator Vidisha Parasram. "The tank hatches had no mechanism which would permit them to be secured or locked. No fire or explosion warning signs or other warning signage was visible anywhere on the site following the accident." Ms. Parasram said the CSB would continue to study whether
any signage could have been destroyed in the fire, but that even the undamaged portions of the facility and the entrance gates had no posted warnings. Eyewitnesses said they saw no signs on the night of the accident o
r during previous visits to the site.
The site entrance was protected only by an unmarked gate which multiple witnesses described as being wide open on the night of April 14, and generally open and unlocked at other times. Apart from the gate the site had no fencing or other protective measures that would keep members of the public safe from hazards on the site.
"Following this accident, our investigative team was able to observe a number of other oil and gas production sites in the area. The vast majority were unsecured and had no warning signs," said CSB Investigations Supervisor Don Holmstrom, who leads the CSB regional office in Denver. "Oil and gas sites that lack security measures and warning signs are an accident waiting to happen." State officials told the CSB that Oklahoma has approximately 257,000 active and unplugged oil and gas production sites; Oklahoma requires fencing and warning signs only at sites that have toxic hydrogen sulfide gas hazards, according to state officials.
The deadly blast occurred one day after the release of a new CSB safety video at a public meeting in Hattiesburg , Mississippi . The safety video, "No Place to Hang Out," is aimed at educating young people on the hazards of socializing at oil sites, a common practice in rural areas, the CSB found. The video tells the story of the tragic deaths of 18-year-old Wade White and 16-year-old Devon Byrd, killed October 31, 2009, when an oil tank, located in a clearing in the woods near the home of one of the boys in the rural town of Carnes, suddenly exploded while the two were hanging out at the site.
Frequency of explosions at oil sites is quite high due to inflammable nature of oil
A CSB preliminary analysis released on April 13 showed that 24 similar explosions and fires occurred at oil and gas production sites between 1983 and 2009. Those accidents resulted in 42 fatalities and a number of injuries; all the fatalities occurred among teenagers and young adults under the age of 25. In most cases, the explosions were ignited by a cigarette, match, or lighter. The CSB found no specific federal standards or industry guidance for security or public protection measures at oil and gas production sites. Certain states including Ohio and Colorado require fencing and other public safety measures at sites in urban areas. Ohio requires tank hatches to be sealed and locked at unattended oil sites.
Counting the accident on April 14, the CSB has thus far identified a total of seven oil site explosions and fires in Oklahoma since 1990 that killed or injured members of the public, the highest total for any state. Four of these accidents caused multiple fatalities.
CSB Board Member William Wark said: "The CSB is concerned about these ongoing accidents across the country that are needlessly taking the lives of young people. To me, it is self-evident that hazardous oil and gas sites should be secured against unauthorized entry and posted with extensive and specific warning signs. And we need to educate teenagers and young adults to stay away from these sites - they are dangerous." Mr. Wark said the CSB team received outstanding cooperation from local law enforcement and fire officials during the investigation.
The day prior to the explosion in Weleetka, the CSB Board issued a statement "urging oil and gas production companies to ensure that they provide adequate security and warning signage around sites that have tank fire or explosion hazards; and further urging state legislatures, local governments, and regulators to review rules governing oil and gas tank sites to ensure they require adequate barriers, security measures, and warning signs." Mr. Wark said a CSB task group will be working over the next several months to develop additional specific safety recommendations, incorporating the findings from the recent accidents in Mississippi and Oklahoma .