Local News

CSB: Purged gas line may have caused blast

Posted June 18, 2009

— The U.S. Chemical Safety Board said Thursday that natural gas purged from a line to a new water heater likely caused a fatal explosion last week in a Garner food plant.

Investigators from the Bureau of Alcohol, Tobacco, Firearms and Explosives determined last weekend that a gas leak caused the June 9 explosion at the 425,000-square-foot ConAgra Foods plant on Jones Sausage Road.

The CSB and inspectors with the state Division of Occupational Safety and Health have interviewed 120 ConAgra workers in recent days to determine the cause of the gas leak and how that sparked the explosion.

Don Holmstrom, U.S. Chemical Safety Board Web only: Initial findings in plant explosion revealed

Don Holmstrom, an investigation supervisor with the CSB, said the natural gas line leading to a new industrial water heater was purged on the morning of the explosion to remove air from the line. Outside contractors were working with ConAgra personnel to put the gas line and water heater into service, he said.

Investigators are looking at the possibility that the purged gases were vented into the pump room that has been identified as the site of the blast, Holmstrom said. They could have created "a flammable gas cloud" that exploded, he said.

The spark for the explosion hasn't been determined, Holmstrom said, and it might never be found because of the extensive damage in the plant.

"The current focus of our investigation is to determine why flammable gas was released into the midst of an occupied building with about 100 people in the immediate vicinity," he said.

CSB Chairman John Bresland said he's never heard of someone venting gas fumes inside a building.

"In my mind, that would seem to be a risky operation," Bresland said.

Holmstrom and Bresland declined to name the contractor working on the water heater. Two ConAgra workers filed suit Monday against Southern Industrial Constructors Inc., a Raleigh mechanical contractor, blaming its crew for the blast.

"The people involved in the installation were also involved in the purging," Holmstrom said.

The lawsuit alleges that Southern Industrial improperly installed the gas-fueled water heater in the plant. David Stradley, the attorney for the workers, said Wednesday that permits issued by Garner officials for the work in the plant implicate the contractor in the blast.

Rod Pettey, an attorney for Southern Industrial, said in statements that the company's four employees who were at the ConAgra plant the day of the explosion weren't anywhere near the blast site and weren't responsible. The permits show the crew only tapped into an existing gas main on the plant's roof and didn't work in the pump room, he said.

Investigators plan to examine equipment at the blast site – explosion reconstruction experts are part of the CSB team – and review employee training records, ConAgra's selection of contractors and applicable fire codes and insurance standards as part of the probe.

"We want to be able to examine the incident scene to correlate ... witness statements with exact physical evidence," Holmstrom said.

Bresland said it's hard to determine when investigators will be able to get to the pump room because the site remains very unstable. The blast damaged about 100,000 square feet of the plant, he said.

"It was a very sobering site to see the impact of that explosion. It was a significant explosion and certainly a terrible tragedy for the people involved,” he said.

The CSB also plans to look into the release of ammonia from the plant into a nearby creek following the explosion. Ammonia is a flammable and toxic liquid, and the company uses it in its refrigeration operations.

Holmstrom said part of the ammonia leaked from pipes in the blast, and "a controlled release" was performed to drain the plant's lines and prevent further damage.

Production to resume in August

ConAgra spokesman Dave Jackson said the company plans to restart "limited production" of Slim Jim beef jerky products at the plant in August.  Some production also will be handled by a ConAgra plant in Troy, Ohio, he said.

The blast occurred in the packaging area of the plant, and Jackson said the company plans to hire an outside firm to handle packaging of Slim Jims produced in Garner.

Garner Mayor Ronnie Williams said ConAgra officials have assured him that the company will rebuild the plant and resume full production in the future. The plant employs about 900 people.

"The rebuilding is going to take place in a timely fashion, and the workers can go back to work," Williams said.

Four workers burned in the blast remain in critical condition in the North Carolina Jaycee Burn Center at UNC Hospitals in Chapel Hill. A fifth worker was in fair condition Thursday at the burn center, and a sixth was in good condition.

The hospital erroneously reported improvements in several patients' conditions on Wednesday.


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  • SailbadTheSinner Jun 18, 2009

    You’re going to have to give me a LOT more information than a ‘purged gas line’ caused this. Although certainly possible, it seems unlikely ....

    For example: Exactly how much gas was purged? If you know the size and length of the line, which can both be measured, and the pressure of the NG, which can be determined from regulator settings, then you can compute the volume of the released gas. More important, you can compute the amount of energy that was released when the NG ignited.

    And then, the big question: Was that energy release sufficient to cause the level of damage that was actually experienced?

    I’ll be interested to read the report when there are enough details to make an engineering assessment of what really happened.

    But, these things take time. After all, when you rush a miracle man, you get lousy miracles ....

    I’m patient. I can wait ....


  • Stringbean Jun 18, 2009

    "The U.S. Chemical Safety Board said Thursday that natural gas purged from a line to a new water heater likely caused a fatal explosion last week in a Garner food plant"

    NO WAY!....lets just say it might have started out as a "purge".but what some one did was he/she left the valve or the end of a line open for one heck of a long time....this was more than a water heater or 2...or 5 dont let them fool ya

  • mrduffin Jun 18, 2009

    I hope Southern Industrial had licensed people supervising the job. If not their goose is cooked! I used to work for a school system in maintenace and they will hire anybody to work on the gas equipment because it is cheaper than hiring a licensed person. One of these days there is going to be an explosion that hurts lots of people like what happened at Con-Agra. Until then unlicensed, unqualifed people are working on the gas boilers and water heaters in your kids schools. When I worked there I was the licensed person but I made too much money so they replaced me an unlicensd person when I retired. Southern Industrial will see the extra money is well spent if their on-site supervisor was not licensed!

  • ranquick Jun 18, 2009

    I bet the guy who spoke out last week against COn-Aga feel like a heel now, he put his foot right in his mouthand why, simple some lawyer looking to make a HUGE quick dollar put thoughts in his head abut sueing for millions... and we still not sure what happen, I thin they said "Might Have". I do not blame the families for Law suits.. I blame Liars oh sorry Lawyers who chase cases like this just to make a quick dollar on someones tragedy.

  • EverythingTicksMeOff Jun 18, 2009

    Allright! Now we know that the lawyer who filed the law suit is wrong as to the cause of the explosion and who might be responsible. I guess the lawyer will just have to amend his lawsuit to change it to his next theory.

  • 5-113 FA Retired Jun 18, 2009

    CSB: Gas purged from new line may have caused blast

    Key words here: "MAY HAVE" That's certainly enough proof for me. I'll take mine in $10's and $20's please, and while you're at it, wash my car.

  • mrduright Jun 18, 2009


    What "type" of people are refering too?

  • clintoflannagan Jun 18, 2009

    Well whether they are ambulance chasers or not it looks like they might be right. And if they are right then it looks like an absolutely preventable tragedy.

    With that said, I still agree with everyone who has raised questions about how this lawyer filed the lawsuit so fast.

  • oldfirehorse Jun 18, 2009

    If it is proven that someone purged an NG line inside the building then whomever they work for needs to be sued into the next century. That's about the stupidest thing I can imagine. Purge the line into an enclosure to avoid an explosion in the line/equipment without having been purged. If it weren't so tragic it would be hilarious.

  • Justabum Jun 18, 2009

    The ambulance chasers have their cars gassed and are ready to roll.