As industrial emergencies go, the February 2009 fire in a 679-foot tunnel used to move petroleum coke beneath a busy Los Angeles County rail corridor did not get much press. One official spokesperson stated it was "relatively insignificant" and "fairly minor."
Los Angeles County Fire Department Battalion Chief Bruce Arvizu said he found the press release understandable considering today's overblown reactions to such incidents.
Addressing an audience of industrial firefighters, Arvizu discussed the recent fire as one of the opening speakers at the 2009 Industrial Fire World Emergency Responder Conference & Expo in Beaumont, TX, in March.
Disagreement still exists whether two loud, earth shaking blasts reported during a confined space entry by firefighters were coal dust detonations or some other type of concussion.
"Talk about a near miss," Arvizu said. "This was a near miss. I'm glad I'm not talking about fatalities."
Major financial considerations also figured in the emergency. The tunnel ties together two halves of a 265,000-barrel per day refinery, among the largest in California. According to the owners, it supplies about 25 percent of the Los Angeles gasoline market.
Splitting the 630-acre refinery is a 20-mile dedicated freight expressway known as the Alameda Corridor, which the tunnel runs beneath. The corridor links the ports of Los Angeles and Long Beach to the transcontinental rail network near downtown Los Angeles.
"It's about ten rail tracks wide," Arvizu said. "A lot of commerce goes through there. If I had to shut that down, which I have done before, I've got senators and the governor breathing down my neck. It's about $4 million every 15 minutes to shut this rail head down."
Despite early success, firefighters were forced to abandon confined space entries in favor of flooding the tunnel with more than 400,000 gallons of water.
"In hindsight, we probably could have compressed that incident to less than two hours had we gone with gut instinct to flood it in the beginning," Arvizu said.
In 31 years as a firefighter, the fire in Carson was Arvizu's first involving a tunnel. Before arriving on scene for the February 23 fire, he had no idea that this particular tunnel even existed.
"I've trained on tunnel fires," Arvizu said. "Our jurisdiction has had some of the largest tunnel fires in California history. But I'd never been involved in an actual incident."
Likewise, none of the key personnel under his command had direct experience with tunnel fires.
Measuring 10 feet in diameter, the tunnel beneath the Alameda Corridor has been part of refinery operations since 1964. It houses a conveyor belt that moves coke, a petroleum byproduct that is 99.9 percent carbon, from a coker unit to a storage barn.
At about 3 p.m. the conveyor belt stopped operating. By about 5 p.m. workers noticed smoke coming from the tunnel opening.
"There is no fire protection or life safety system in that tunnel," Arvizu said.
Los Angeles County firefighters at the nearest station were just coming back from a drill when the telephone rang. It was the refinery fire chief.
"Our relationship with the refineries is so good that a lot of times they call us directly on the cell phone and talk to us personally," Arvizu said. "We all become creature of habit like that. Had the firefighters been out I'm not sure how we would have gotten the alarm."
Arvizu, a battalion chief for nine years, is responsible for a heavily industrialized region of south-central
"Battalion 7 gets the lion's share of large fires," he said. "We get probably two good fires a year that are second and third alarm fires. That means you've got 15 to 20 fire engines."
Shortly after the refinery contacted firefighters, Arvizu received notification from dispatch.
"They said 'We've got something going with an alarm call,'" he said. "I said 'Well, what do you have?' The dispatcher said, 'We're not sure.'"
The tunnel, about 200 feet down, runs east to west. Arvizu met with the refinery fire chief at the west side of the tunnel which was then designated "Division A." It was one of only two openings available for maintenance and personnel.
"Once we got there the refinery chief said, 'Well, it's not a big deal, just a coke fire,'" Arvizu said. "I said 'Copy – Is it in the coke barn?' 'No,' he said, 'it's in the tunnel.' I said to myself 'Tunnel – oh God!' You've just got a gut feeling that it's not going to be a good deal."
Technical information available about the tunnel was limited. It was built using a combination of corrugated pipe and cut and cover construction.
"Just dig a big trench, pour and place the cement, then cover the top of it," Arvizu said. "Then pour your dirt or ballast over that. It's a real cheap way to go and offers pretty good integrity."
Flooding the tunnel was his first inclination, he said. A sign posted at the tunnel entrance lent credence to Arvizu's original thought.
"It said 'Equipment structure integrity issues – possible sharp edges, tripping hazards, access and egress issues, fallen debris, visibility issues, hot coke, energized power lines,'" he said.
Beside the conveyor system, the tunnel contained about a foot of water and product debris, owing to a plugged drain. Elevation dropped 15 feet moving from east to west. Because of an onshore breeze, smoke was not much of an issue in the vestibule where the coke collected outside the tunnel.
"When we looked into the tunnel originally, we could see a glow of fire and smoke about 75 feet in," Arvizu said.
A response for a confined space incident in a refinery is probably the largest first alarm that the Los Angeles County Fire Department musters, he said. Firefighters responded with six fire engines, two trucks, a hazardous materials unit and an urban search-and-rescue team.
"The reason why it didn't go to a second alarm is because the refinery had a good cadre of firefighters, bringing about 30 or 40 folks," Arvizu said. "I really didn't need more resources because we train with these folks a lot. It's a good relationship."
Two captains that Arvizu dubbed as his "superstars" supported a confined space entry to attack the fire. He put his initial inclination toward flooding on the backburner.
"I'm a great believer in listening to my folks," Arvizu said. "I had confidence that it was a good plan, a workable plan. I said 'Okay, we'll just do it like a Level A entry with Level B clothing.'"
Organizationally, duties were divided between incident command and operations.
"The refinery has a fire chief and an assistant chief," Arvizu said. "We tried to marry the fire chief with IC and the OPS chief with me. It works out really well."
Arvizu said his rule on organization is to keep it as simple as possible.
"I took operations and logistics, but felt I was stretched a bit thin," he said. "If I had appointed a logistics chief, I would have given him the water group, medical and ventilation. I like to break it down to just three division groups reporting to me – fire attack,
The overall strategy was offensive, Arvizu said.
"My objective was tunnel access, locate the fire, confine it and ventilate," he said.
Any confined space entry depends on rigorous fire ground controls following NFPA guidelines, Arvizu said.
"That means setting up your
Communications, often challenging on the fire ground, were well in hand at the tunnel emergency, Arvizu said.
"We have low megahertz for tactical radios," Arvizu said. "Command radios are high frequency. We were always in contact. In fact I had four frequencies going. At all major incidents I have a command frequency, an entry frequency, a tactical frequency and an administrative frequency."
Firefighters are able to isolate those frequencies from the multitude of other emergency radio traffic ongoing in
"I hear only what is going on at the incident," Arvizu said. "I don't hear about a rescue in South Central LA or a shooting or whatever."
Firefighters who made the initial entry later reported being very uneasy, Arvizu said.
"They were walking through a foot of water in close proximity to the wall," Arvizu said. "The ground was uneven with coke slurry. You've got all kind of pipe going through there." Add to that the difficulty of hose handling in a confined space, requiring assigned hose handlers.
Still, the report from that first team was reassuring, Arvizu said. Using two 1¾-inch lines, firefighters moved 75 feet down the tunnel to confront the fire.
"The guys said, 'We knocked the fire down,'" Arvizu said. "Visibility was down to zero because we had our ventilation set up behind us. We used Tempest positive pressure ventilation blowers operating at about 48,000 cfm to push everything ahead of us when we made our entry."
Firefighters exited the tunnel covered in coke dust. The first stop was gross decon, followed by rehab.
"I had our medics set up to take baselines," Arvizu said. "Believe it or not, about 20 percent of our people did not get out of rehab really quick because their baselines were a little bit high. After about 20 minutes, they recovered."
"I told them '100 feet or 10 minutes on air,'" Arvizu said. "It gives them one-third in and two-third air to come back out."
If the firefighter cannot reach that 100-foot mark, his play pipe still gives the chance for penetration, he said. On a commercial fire, advancing to 150 to 200 feet inside increases the risk versus benefit ratio exponentially.
"If something goes wrong, your chances of surviving are very, very small," Arvizu said.
One essential piece of safety equipment that Arvizu carries is an egg timer.
"I set it for 10 to 14 minutes," Arvizu said. "Guys make fun of it but if you look at fires historically, if things aren't improving within 14 minutes it's time to change tactics. If it's getting better, you get a bottle change and go back in. If it's getting worse, you pull everybody out and regroup."
Again, the firefighters exited the tunnel with a positive report.
"They said 'The thermal balance is down to 170 degrees F -- it's a cold smoke fire,'" Arvizu said. "They thought that a third entry would get it."
The refinery fire chief wanted to check for himself. Thinking this would be the last entry necessary, Arvizu expected to again penetrate the tunnel at least 75 feet. Procedure would be the same as before, with firefighters rotating every 10 minutes until the fire was out. The only difference was Arvizu ordered the use of one-hour air bottles.
"We have about 20 one-hour bottles we can put immediately at a fire and get 20 more if we need them from outlying companies," Arvizu said.
The specific mission of the third entry was reconnaissance to check for damage to the integrity of the tunnel and extinguish the remaining fire. Firefighters descended to tunnel level and were about to enter when the first of two resounding concussions like sonic booms were heard. After the concussions, heavy black smoke and large flame erupted from the tunnel.
For Arvizu, the moment brought an unpleasant flashback.
"I heard the entry team safety officer say 'Okay, that's it, everybody out,'" Arvizu said. "We were in
Later, Arvizu had the opportunity to question firefighters who were above ground on the Division A side of the tunnel when the 'loud concussions' were heard.
"One firefighter said 'Chief, I was in fear of my life,'" Arvizu said. "He said the ground shook enough that he lost his balance. This guy was a 6-foot, 4-inch body builder type. He said 'Honest to God Chief, I looked at the truck and it was shaking like a rag doll. We immediately jumped in and drove it another 100 yards away.'"
The cause of the concussions is still under investigation. That cause will likely be electrical, mechanical or product related, Arvizu said.
"Some people say it was concrete spalding off the walls," Arvizu said. "I walked that tunnel three days later. Where it was supposedly spalded looked like a nuclear bomb went off. All the metal light fixtures were bent and melted."
By 8:20 p.m., the incident commander decided to flood the tunnel after reviewing all available options.
"It was suggested that we use high expansion foam," Arvizu said. "We talked to Ansul to get some calculations. The Ansul representative was concerned that due to the length of the tunnel and the 15-foot elevation as much as two-fifths of it could still be burning after foam was introduced."
In hindsight, one alternative unexplored was using compressed air foam (CAF), Arvizu said.
"It never occurred to me until I talked to (IFW chairman) David White and other people," Arvizu said. "In
Within two hours, firefighters flooded the entire tunnel using 4,300 gpm of water delivered at both entrances. Runoff was diverted to the refinery's clarifiers that easily handled the load.
"It was cheap and simple," Arvizu said. "In hindsight, we learned much and probably will not make an entry like that again."
Aside from flooding as a first step, Arvizu said he would have changed several other aspects of the confined space entry. Increased staffing for the
"I probably should have had another 10 folks there," Arvizu said. "Not that you're going to need 24 people, but
Firefighters can be as bad about rubber necking as civilians. One problem at the tunnel fire was that entry teams waiting their turn tended to crowd the entrance to see what was going on.
"In the future I would assign a captain to get the teams together and cue them up about 50 yards away," Arvizu said. "That involves discipline."
Maintaining discipline proved to be a problem in one other episode, he said. At one point, Arvizu turned to his safety officer and asked him to set up rehab. He refused.
"Safety officers are great people, but they get so focused in on doing one thing that they are not very versatile," Arvizu said. "I said 'Just take a minute or two and get it going.' He said, 'I can't – I'm the safety officer.' So, we went toe to toe over that."
Arvizu said he has already scheduled a confined space awareness class for his division. He has also launched an effort to identify and pre-plan all industrial tunnels in his jurisdiction.
"I have found three more," Arvizu said. "That makes seven, including a long train tunnel and several vehicle tunnels."