Sedgwick County (Kansas) Fire District Deputy Chief Rick Brazill made a split-second command decision. Nine hours into a fire involving 40 vertical storage tanks burning at a wholesale chemical distribution center, firefighters poured water on the tank farm for 15 minutes straight in preparation for an attack using alcohol-resistant foam.

 "We had knockdown," Brazill said. "But about the time we got ready to start the foam the top of a tank blew off. It scared everyone. My safety officer was ready to shut the operation down and pull everybody out."

Brazill decided to continue. It would prove to be a critical choice in that both water and foam were in relatively short supply. Soon a solid foam blanket was in place across the flammable liquids filling the common dike, extinguishing much of the fire.

"If it had taken another 10 gallons we would have been in trouble," Brazill said. "We made a choice to attack and extinguish it and the plan worked. We had somebody looking out for us that day."

Nine hours earlier, a tanker truck offloaded varnish-makers and painters (VM&P) naphtha at the tank farm in question, located in Valley Center, north of Wichita. The naphtha was pumped into a 15,000-gallon aboveground storage tank designated Tank 31, located on the south side of the tank farm, said Valley Center Fire Chief Lonnie Tormey.

That tank exploded during the offloading, creating a huge fireball over the city. The tank lid, blown off by the blast, cleared the entire tank farm and landed north of the distribution center.

Beside naphtha, bulk storage at the site included oil, diesel, mineral spirits, acetone, toluene and xylene. Flames spread through the tank farm, triggering numerous explosions involving storage tanks with capacities ranging from 3,000 to 20,000 gallons. At least one home and a nearby business suffered structural damage from flying debris.

The July 17, 2007, incident eventually led to the evacuation of thousands of Valley Center residents. Difficulty locating adequate foam supplies delayed extinguishment. Although the tank farm was a total loss, firefighters saved an adjoining warehouse with an inventory of the same flammable liquids packed in 55-gallon drums.

In Valley Center, population 6,000, the fire department consists of a full-time fire chief, one other full-time firefighter and 24 volunteers. All Valley Center Fire Department personnel hold state certification as Firefighter I, Firefighter II and hazmat operations level.

Working from one fire station, the Valley Center F.D. has two engines, one rated at 1,500 gpm engine and the other at 1,250 gpm. The department also has two squads or grass trucks and a tender.

"That takes care of the majority of everything we have around here," Chief Tormey said. "The department added the engines and tenders because thanks to recent annexations Valley Center is almost 40 percent without hydrants."

Local firefighters regarded the distribution center as a very safe operation, he said.

 "They don't do any refining, just storage and bulk delivery," Tormey said. "There is a warehouse stacked with 55-gallons drums delivered to the aircraft plants and aircraft parts companies in Wichita. They had a lot of cleaning solvents, even soap and some motor oil."

Firefighters knew about the emergency before the first dispatch call. Shortly after 9 a.m. Tormey heard the first blast as he was standing outside the Valley Center fire station.

 "I didn't know what it was but it sounded like more than just a transformer blowing," he said. "It wasn't 30 seconds later that there was another explosion."

By the time Tormey reached a fire truck, a local police officer en route reported a massive black cloud rising above the southwest part of town. It was first thought that a grain elevator two blocks away from the distribution center had exploded.

"The station is only three-quarters of a mile from the plant," Tormey said. "As soon as we got halfway we could tell it was the chemical storage facility instead. It was awful dark from the black smoke."

Mayhem greeted Tormey at the distribution center. Explosions continued to rock the tank farm, hurling fireballs and debris skyward. In addition to the burning storage tanks, a tanker truck involved in the offloading at the time of the first blast was on fire.

Thanks to a lack of wind, the thick smoke rose straight up, Tormey said. Most of the surrounding area was zoned industrial, but a residential neighborhood lay north of the facility. Still, the decision was soon made to start evacuating a 10 block radius. Police proceeded to the nearby residential neighborhood to go door-to-door.

Even before reaching the scene, Tormey requested mutual aid from the Wichita Fire Department and the Sedgwick County Fire District. Within the first 10 minutes of the emergency, Brazill arrived with a quint from a Sedgwick County Fire District station eight miles away. A quint, or quintuple combination pumper, is an apparatus that serves the dual purpose of an engine and a ladder truck.

The fire district includes 17 Sedgwick County towns smaller than Wichita and Valley Center. However, much of the district is anything but rural. Major industries covered by the district include Boeing, Cessna, Lear Jet, Raytheon, two major chemical plants and a grain elevator. The district includes almost 100,000 residents.

"Sedgwick County is pretty well seasoned in handling natural disasters," Brazill said. "We've had tornadoes, floods, all kind of events in the last four or five years. We are well practiced in setting up incident command and working together with different agencies within the county."

Tormey and Brazill found the distribution center's manager waiting at a timber products business across the street. He informed them that all 20 employees were accounted for and had been safely evacuated.

"I asked him what he had, and he said it was all alcohol based solvent products," Brazill said. "He said the tank farm had a 640,000-gallon capacity. I asked him what the capacity of the tank farm's dike was. He didn't know."

The tank farm was arranged in three rows with the tallest tanks, about 40 feet high, on the west side nearest the warehouse. The lowest tanks, about 15 feet tall, were arranged on the east side with a row of intermediate height between.

"Each tank had a pipe coming out of it leading to a loading dock at the warehouse," Tormey said. "That's where they loaded and unloaded semis. That one corner of the west warehouse was probably 30 to 40 feet from the tank farm."

The tallest tanks averaged about 10 feet in diameter, while the shorter tanks ranged from five to six feet in diameter. All but four of the tanks sat in the same common dike. On average, the tanks only had about three feet of space between them.

Other than a decent set of hydrants fed from a 750,000-gallon water tank within half a mile of the site, the tank farm had no fixed fire systems in place, Tormey said.

Among the immediate concerns was flame impingement on the warehouse, Tormey and Brazill said. Tractor-trailer rigs parked east of the tank farm were subject to intense radiant heat. Also, five railcars containing dry cleaning solvent were parked next to the warehouse.

The first critical decision made by Tormey and Brazill was that Brazill would take charge as incident commander. Tormey chose to remain on scene with the firefighters. Initially, a command post was established only a few blocks away. Later, responders moved it several blocks further away to a local Masonic lodge.

"We tried to make it a unified command," Brazill said. "Chief Tormey was out in the trenches helping the firefighting forces. I was really in the command post with the city manager and the mayor. I kept them advised on what we were doing. They made the ultimate decision as far as their citizens and their city, but I gave them options."

City officials decided to extend the evacuation to the entire community, Tormey said.

"So much was unknown," he said. "We decided we might as well do the whole town because we were having trouble locating a sufficient quantity of foam to start extinguishing."

Access to move equipment into position was limited by several factors, Brazill said. The single gate into the center led into a parking lot filled with tractor-trailer trucks. Firefighters were forced to enter via the parking lot of an adjoining business on the west side of the center, cutting a fence in the process.

Establishing a water supply, responders used the fire district's quint, together with unmanned monitors, to protect the warehouse exposure.

"Our access to this place was horrible," Brazill said. "We had semis on fire, barrels blowing up and we didn't feel comfortable putting fire apparatus in close to those tanks because we didn't know the capacity of the dike."

Railroad officials were not anxious to risk their personnel to move the threatened railcars without assurances from the fire district about safety, Brazill said.

"Our fire district has a position designated as railroad liaison," Brazill said. "We're pretty close with the railways throughout the Wichita-Sedgwick County area. They are very cooperative. We have direct radio contact with them. We had to shut down railroad traffic through Valley Center."

Radio communication between responders at the scene proved to be more difficult, Brazill said.

 "Everyone within the county is on an 800-megahertz system, except for Valley Center," Brazill said. "We kept a law enforcement representative from Valley Center close by who had direct radio communications with the Valley Center fire units."

Cell phone communications held up throughout the entire emergency, he said.

The situation at the tank farm worsened. The tanks were equipped with manways close to the ground for maintenance. With the fire spreading across the flooded dike, the gaskets around these manways soon burned away, dumping even more flammable liquid to the ground.

"We were working with 360-degree, three-dimensional fires – in the tanks, on the tanks, between the tanks," Brazill said. "We had flange fires and lots of product in the dike that was burning."

Both Brazill and Tormey agreed that foam was needed. Valley Center only kept a couple of gallons of foam on hand, none of it AR/AFFF. Likewise, the fire district only carried about 25 gallons of Class A and B foam on its trucks.

 "We contacted McConnell Air Force Base and Boeing," Brazill said. "They sent out two big crash trucks."

Unfortunately, the crash trucks proved less than successful.

"They couldn't get the foam up over that tall row of tanks to do any good," Brazill said. "Also, the AFFF foam the crash trucks carried was not alcohol resistant foam. It wasn't compatible with the product that was burning. They'd knock the fire down and as soon as they shut the foam off, it would flash back again."

Despite thousands of gallons of foam, the tank farm continued to burn. Also, as Brazill feared, firewater overflowed the dike.

"We did get some of it in the sewer system," he said. "It killed the bacteria and for a couple of days they were dumping raw sewage into the Arkansas River."

Responders decided to step back and reconsider the situation, Brazill said.

"At that point we kind of retreated," he said. "We decided 'Okay, we're keeping it out of the warehouse, and we have all the citizens evacuated to a safe distance. The fire wasn't going anywhere."

Brazill said he leveled with the Valley Center officials about the chances of extinguishment.

"I told them that we may just have to let it burn out," he said. "Right now we've got it in check and nobody is in danger, but this thing has the potential to burn for a couple of days. Of course, nobody wanted to hear that but they understood why."

Nearly four hours into the emergency, Brazill got good news. A supply of alcohol-based foam had been located at the 110,000 barrels-a-day Frontier Refinery in El Dorado. Given his choice of receiving the foam in 55-gallon drums, a tanker or a 1,250 gpm pumper, Brazill chose the pumper.

"When the pumper arrived, Frontier's fire chief, David Zorn, was on it," Brazill said. "He had been a member of our department before he went to work at the refinery."

After Brazill and Zorn conducted another reconnaissance of the fire scene, a new operations plan was devised. First, the unmanned monitors would be deployed against new targets since fires at the south end of the tank farm no longer threatened the warehouse.

"Some of the south side tanks were no longer burning because they were either out of product or the wind was pushing the vapors north," Brazill said. "The monitors had also been assigned to fires involving barrels loaded on trailers. Those had been extinguished."

A tractor-truck would be employed to move trailers that had not burned to give Zorn room to position his pumper to best use the deck gun. Before hitting the fire with the alcohol-based foam, the Frontier pumper and the fire district's quint would be used to cool the tanks with water and achieve knockdown.

This plan qualified as a last-ditch effort for the fire district, Brazill said.

"If we hadn't gotten it, it was going to burn for several days," Brazill said. "There was no way that I could commit resources for several days outside our jurisdiction."

Firefighters tied into another hydrant several blocks to the north that supplied them with another 2,000 gpm. However, this involved moving hose lines and relocating apparatus.

"We were taxing the Valley Center water system," Brazill said. "We didn't know if we'd have enough water to do what we wanted. I advised the Valley Center officials about what we were going to do and they jacked up the pumps at their water treatment plant to give us some additional water. We put a pumper down at the new plug and put a relay pumper between it and the fire."

Firefighters began the operation at about 6 p.m. The last previous explosion in the tank farm had been before noon. As before, firefighters achieved knockdown with 15 minutes of water poured onto the tank farm. Then, before the foam attack could begin, the lid blew off one of the 15-foot tanks.

"I kind of second guessed myself on whether that was the right decision to continue," he said. "But we poured the foam to it and blacked out the fire. We used every bit of foam that Frontier had brought."

Experts later determined that the final explosion was not a BLEVE as originally thought, but an air pressure release.

"We had cooled that tank using the aerial device," Brazill said. "Then we redirected the stream onto some other tanks. In the process, the vent on the first tank sucked in a big gulp of air. When the tank heated up again, it blew the top of the tank off."

Responders used fire extinguishers to put out the last of the flange fires, being careful not to disturb the foam blanket covering the dike, he said. Later, Brazill requested more foam from Boeing to maintain the foam blanket.

"Again, they didn't have alcohol resistant foam," he said. "We thought getting a foam blanket down to suppress any vapors, even if it wasn't compatible, was better than nothing."

Fire district personnel remained on scene until midnight, Brazill said. Valley Center firefighters stayed several days until an environmental company hired by the distribution center's owners took over the site.

Good firefighters always reevaluate their efforts after a major incident. After the Valley Center fire, the fire district undertook a reappraisal of resources immediately available in the event of an industrial emergency, Brazill said.

"It opened our eyes," he said. "Come to find out we had a resource right here in the county that we overlooked. Vulcan Chemicals had about 2,000 gallons of alcohol resistant foam concentrate in 55-gallon barrels that we could have had for the asking."

Lessons Learned

  • Fire departments must perform pre-plans on special hazards. All commercial properties should be pre-planned, but, as a bare minimum, pre-plan all special hazards such as tank farms.
  • The correct type of foam must be either on hand or firefighters should know where to obtain it in an emergency.
  • It should be realized that with the type of tanks in this tank farm have the potential to blow out at the bottom as well as the top. If any bottom had blown out, it could have exposed firefighters to a very grave situation.
  • Storage tanks are designed with a weak roof weld that allows the roof to blow off rather than have the tank blow out at the bottom. The problem is the weak roof weld joint may not even work on small tanks less than 50 feet in diameter.
  • Some of these tanks were dome roof tanks. Those types of tanks are much more likely to blow out at the bottom than cone roof tanks.
  • Fire departments must control and monitor the water in dikes as it can cause major runoff problems as well as spreading the fire.
  • The runoff from flammable liquid fires can cause as much damage as the fire. Fire departments must monitor this and, in some cases, allowing the fire to burn out may be the best solution.

The firefighters at Valley Center did a great job. They handled this major event without getting anyone injured or killed.