Firefighters cool the remains of a collapsed fuel storage tank at Buncefield. - Photo courtesy of Herfordshire Constabulary.

Firefighters cool the remains of a collapsed fuel storage tank at Buncefield.

Photo courtesy of Herfordshire Constabulary.

For Kelvin Hardingham, fighting the fires that spread through the Buncefield oil storage depot north of London in December 2005 too often became an exercise in futility. With 20 fuel storage tanks ablaze on site, some had to be extinguished not once but repeatedly throughout the three-day emergency.

"As a matter of fact, we put out two tanks at least four times," Hardingham said."You get a little fed up putting the same tank out time after time."

Due to environmental concerns that runoff would pollute the nearby drinking water supply for North London, authorities repeatedly cut off water to the firefighters. This made it impossible to gain control of the many fires in fuel storage tanks that were mostly in the 60-foot diameter range but some as large as 145 feet. Pressure fires from ruptured lines and fires in the containment dikes surrounding the tanks also swept through the facility following the largest explosion and fire in England since World War II.

Eventually, many of these fires simply burned themselves out, Hardingham said.

Hardingham, the U.K. representative for Williams Fire & Hazard Control, first served as a technical advisor to local authorities during the Buncefield emergency, then graduated to a hands-on role as the operational firefighting coordinator onsite.

"To say this fire was a success in terms of extinguishing is probably untrue," he said. "But things certainly weren't in our favor. Most of all was the water supply. If you're constantly having your water supply cut off, your likelihood of success is very low."

Before December, the Buncefield terminal might not have been famous, but it was important. The depot provided eight percent of the U.K.'s overall oil supplies. Across the southeast U.K., that figure rose to 20 percent. Located about 25 miles from London, the 50-acre Buncefield depot interacted with various refineries across the U.K. via three different pipelines. A fourth pipeline supplied 40 percent of the aviation fuel used at London's Heathrow Airport, the world's third busiest airport. Buncefield also supplied London's Gatwick Airport, the second largest U.K. airport.

About 40 percent of the Buncefield depot on its north side is taken up by the east and west units of the Hertfordshire Oil Storage Terminal, a joint venture between Total and Chevron. In 2004, 2.34 million metric tons of fuel passed through the HOSL units either by pipeline or the nearly 400 tanker trucks loaded each day on a 24-hour basis. Products stored on site included ultra-low sulfur diesel, unleaded gasoline, super unleaded motor spirit, kerosene, gas oil and aviation fuel.

It was the north side of the depot that bore the brunt of the explosion and subsequent fires. A BP Oil terminal divided this area from the rest of the depot but experienced little damage from the blast.

"There was no on-site firefighting crew at Buncefield," Hardingham said. "This wasn't a terminal that justified having its own dedicated fire crew."

What caused the explosion that rocked the southeast U.K. at 6 a.m. on Sunday, Dec. 11, remains a matter of conjecture. Reports issued by the Buncefield Major Incident Investigative Board point to a tank overfill in Tank 912 at HOSL West that created an immense vapor cloud. The cloud flowed offsite to nearby unrelated businesses, eventually finding a source of ignition.

"The explosion registered 2.4 on the Richter scale," Hardingham said. "There were three or four smaller explosions within the next 10 minutes. Fortunately there were only 43 people injured. I say fortunately because had this occurred at 11 a.m.on a Monday, all these nearby factories would have been full of people."

Smoke spreads across the southeastern U.K. from the Buncefield oil depot. - Photo courtesy of Chiltern Air Support Unit.

Smoke spreads across the southeastern U.K. from the Buncefield oil depot.

Photo courtesy of Chiltern Air Support Unit.

Before joining Williams F&HC in 1996, Hardingham served 30 years in the U.K.municipal fire service, the last 10 spent as the liaison between the municipal fire service and the petrochemical industry.

"That's when I was introduced to Dwight and his late father Les, and we brought the Williams F&HC Big Gun technology to Europe," Hardingham said.

Holding world records for massive extinguishments, Williams F&HC is known for innovative technologies in extinguishing agents, nozzles, fixed and portable monitor systems, hose and other components of firefighting delivery systems.The largest monitor nozzle in the ground-breaking Big Gun line can deliver 15,000 gallons per minute.

People more than 200 miles away in France and the Netherlands heard the initial Buncefield explosion. Hardingham, living 110 miles from Buncefield in Leigh-On-Sea, Essex, could see the smoke spreading across the southeastern skies of England when he left for London that morning.

"It was daylight, but it was like night at the railroad station," Hardingham said.

Hardingham did not become directly involved at Buncefield until 18 hours after the initial explosion. The trip to London was at the request of Sky News, the U.K.equivalent of Fox News. Hardingham's 40 years of firefighting experience was employed first as a television commentator covering an event drawing media attention across Europe and beyond.

Aerial photographs supplied by the Hertfordshire Constabulary and the Chiltern Air Support Unit revealed the extent of the devastation. Beside the storage depot, surrounding commercial buildings owned by Fuji Film and other companies had sustained substantial blast damage. Glass and other exterior materials had been stripped away. Contents of the buildings littered the surrounding countryside.

"About a mile south were the European offices formerly used by BP," Hardinghamsaid. "It was fairly modern with quite large offices. There was a glass atrium that stood as tall as the 11-story building. It was cracked from top to bottom and quite seriously damaged."

These surrounding buildings were the opening challenge for firefighters, even before operations at the depot could begin, Hardingham said.

"The buildings had a maze of fire in them," he said. "The firefighters had to go around and figure out if they had anyone in those buildings."

As to the onsite emergency, the first priority was to assess the number of injuries and degree of damage. Information in those first moments was not easy to obtain. Casualties on site were primarily tanker truck drivers either arriving or departing to make deliveries. No one with a working knowledge of the complete facility could be located immediately.

Buncefield is located only three miles from the center of Hemel Hempstead, population 81,143. The regional fire authority — the Hertsfordshire Fire Rescue Service (HFRS) — had never faced an incident like this before, Hardingham said.

"The only thing they've ever planned for at this site was a single tank fire," hesaid. "To plan for 20 tanks immediately catching fire in one hit plus all the other damage was unrealistic."

In the earliest hours, firefighters busied themselves with the offsite fires. Onsite operations were limited to establishing cooling jets nozzles to protect three tanks not yet ablaze. Hampering even those initial actions was a lack of available water. The explosion destroyed the depot's two fire water pump stations, effectively disabling the entire independent fire water system. Firefighters were forced to draw from a small lake almost 1,000 feet away at a maximum of about 1,000 gallons per minute.

When called upon, Hardingham would play a key role in the command structure governing the emergency response. In the U.K., coordination and management of major emergencies involve three levels of interlinked leadership. Strategic aims are handled by Gold command, the top tier of the command structure.

The second tier, Silver command, that handles tactical concerns, was done away with during the Buncefield emergency. Third is the Bronze command, which directly supervises operations on the fire ground. Hardingham participated at this level.

"My son, Mark Hardingham, with the Essex Fire Rescue Service, responded to the fire with a crew and some Williams F&HC equipment," Hardingham said. "He phoned me about three or four hours after he got there, explaining the situation. He basically said 'Dad, what do we need to do?' So, I talked him through some of the things he needed to consider, look at and plan for."

About two hours later, Hardingham got a call from the office of deputy prime minister John Prescott who had assumed responsibility for coordinating the government's response to the emergency. Hardingham was asked to report to Buncefield as a technical advisor in support of local authorities.

"When I met the fire commander, he said 'Who are you?' — no one had told him I was coming," Hardingham said. "I explained who I was and he said 'Well, you'd better come into the command area.'"

Hardingham's next move came straight out of the Williams F&HC playbook. He spent the next 45 minutes making a reconnaissance of the fire ground. Then he came back with an important question — "Are you sure you want to put this fire out?"

"Even Red Adair said there are times to act and times to walk away," Hardingham said. "The fire was in the middle of a field and not going anywhere. The buildings around it were already destroyed. There were eight or nine tanks that weren't on fire that we could protect. Again, I asked, do we really want to put this out?" The answer he received cited priorities other than those in evidence on the fire field.

"The fire chief had said in the national press that they were going to put it out,"Hardingham said. "Therefore, we're going to put it out."

The Gold command post was almost 30 miles from the actual fire. Hardingham soon deployed to the Bronze command post about half a mile from the incident. He was now the operations firefighting coordinator on site reporting directly to the HFRS Bronze Command structure.

Press briefings reported that nearly 600 firefighters were on hand at Buncefield. However, access to the fire ground itself was tightly restricted to a relative handful of responders.

"Basically, out of the 600 firefighters, there were two guys from [BP], five guys from [SembCorp], five guys from [Total], myself and six guys from the Essex fire brigade," Hardingham said. "If there had been 600 people on that fire ground it would have been a nightmare, so virtually all these other personnel were held back in reserve during the initial firefighting operations."

About the time Hardingham arrived at Buncefield, firefighters had successfully increased the water supply on site to five lines of 6-inch hose. Coping with the water problem had not been easy. The nearest inexhaustible supply of water was a canal about 1½ miles away.

"The concern with the canal was that if you put large pumps on the edge you could destroy the bank," Hardingham said. "If you destroy the bank you destroy the entire canal system. So they decided they could not take water from the canal."

The next available source, two miles away across farmland, had its own drawbacks. With no hard road access, authorities had to use cranes and cherrypickers to lift and place the 2,000 gpm pumps used to relay the water.

"In the U.K. we have what we call the New Dimensions program, which is like your Homeland Security," Hardingham said. "The program purchased 54 2,000-gpm pumps and miles of 6-inch hose. That was what was used at this emergency." Fourteen 2,000-gpm pumps and 12 lines of 6-inch hose relayed water to the fire.

Meanwhile, decisions about strategy were made. Firefighters moved into position in anticipation of getting more water for a foam attack. A 1,000-gpm monitor supplied by Total, two Williams F&HC's 2x6 Guns owned by BP U.K. and ConocoPhillips U.K. and a Williams F&HC 2,000-gpm Patriot II owned by SembCorp were carefully located to attack multiple fires.

"It demonstrated the value of long-range trailer monitors," Hardingham said."People tend to like to get a foam pod and stick a monitor on top of it. That's fine if you can get it into place. But if it's in place and you can't get to it because the infrastructure is collapsing and the roadway is knackered, you're stuck. With the trailer-type mobile monitors, six or seven guys can hump that over the 6-inch hose and the fallen pipe racks."

Twenty hours into the emergency three hose lines became available to fight fire. Cooling operations were reduced in order to supply the direct firefighting. Flames successfully died in the targeted tanks. However, having an inexhaustible water supply is not the same thing as a guaranteed supply.

"What you want for your fire water supply is reliability," Hardingham said. "That is the one thing we did not have. We had to constantly shut down for three and four hours at a time. There we would be fighting the fire and suddenly the water would be turned off."

The Environmental Agency, the U.K.'s version of the Environmental Protection Agency, became a high profile participant during the event, Hardingham said.

"When they said shut the fire water off, there was no argument," he said.

During the incident U.K. officials collected and stored 9 million gallons of firewater runoff with plans to incinerate it. The firefighting foam used by responders contributed directly to the large amount of runoff, Hardingham said.

The explosion destroyed all the foam stored on site at Buncefield. The only foam available in the early hours was brought by municipal firefighters.

Aqueous film forming foam or AFFF, made using fluorocarbon surfactants, is specifically designed to cover burning hydrocarbon-based liquids. However, fluoroprotein foam, made from natural proteins, remains standard issue used by most U.K. municipal departments. Some AFFF-AR (alcohol resistant) foam arrived with the first industrial fire crews and one or two more enlightened U.K. municipal fire brigades, Hardingham said.

"If you can put the fire out a lot quicker, the problems with firewater runoff are less," he said. "If they had used AFFF they would have used considerably less foam."

Worse, some of the foam used — whether AFFF or fluoroprotein — was of questionable quality, Hardingham said. The chemical contents of the concentrate may have settled over time, leaving the firefighters with little more than water to work with.

"When you sprayed some of this foam on the fire, it just sizzled," Hardingham said. "It wouldn't put the fire out."

Tank fires were not the only problem on the rise. Small-to-large pressure fires raging throughout the damaged tank farm had gone largely unchecked. Pressure fires do not respond well to water or foam, Hardingham said. It takes dry chemical and the specialized equipment to extinguish pressurized that has ignited. None of that was immediately available.

Two and a half hours after the first foam attack was interrupted, water to the scene was reestablished and firefighters prepared for a second try. Tanks that had been extinguished had since reignited.

"Remember what I said earlier about the questionable foam," Hardingham said."We got a very questionable tanker load of foam. We off-loaded it into a 4,000-gallon foam pod and from there we were proportioning it out to about 6,000 gpm with a Williams F&HC proportioning unit."

No one knows where the bad foam came from, but the poor quality was immediately apparent, Hardingham said.

"It gave us a real problem," he said. "We were struggling to hold the fire back."

After the first 24 hours, firefighters started receiving factory-fresh foam from U.K.-based Angus Fire, greatly improving the consistency, Hardingham said. Bulk AFFF-ATC foam was available from Europe but never requested by HFRS Command.

On Monday afternoon, one of the tanks not yet burning began causing anxiety. Infrared cameras mounted on a helicopter helped firefighters monitor temperatures on the ground. One particular tank registered an increasingly elevated temperature. The Bronze commander consulted Hardingham on the fireground.

"The HFRS command were very concerned," Hardingham said. "They believed the tank was about to explode like a bomb."

Storage tanks are designed with a weak seam where the roof and sides meet. In the event of an internal vapor ignition, the roof separates and blows off, leaving the tank shell intact. The tank retains its contents and any resulting fire spreads across the surface of the exposed flammable liquid.

"It may go to fire, but a weak seam split between the tank wall and the roof means it will not explode," Hardingham said. "However, I could not persuade the HFRS Command otherwise."

HFRS held the authority in this situation. Unlike in the U.S., municipal fire departments in the U.K. legally take charge of fire operations upon entering a plant or refinery. The senior official with the local fire department is in command. The only exceptions are nuclear plants and military bases.

"A lot of smaller distribution terminals rely on help from municipal departments," Hardingham said. "Unfortunately, many municipal departments have little understanding of the petrochemical industry. For example if you start talking about condensate, they have no idea what you mean. That's no criticism of them because it's not their job. Their roles are more focused on handling such things as structure fires, road accidents, etc."

On the positive side, municipal departments such as the Essex Fire Rescue Brigade make a practice of sending officers and firefighters to the annual Xtreme Industrial Fire & Training event conducted by Williams F&HC in Beaumont, Texas.The weeklong event includes classroom sessions, case studies, hands-on field logistics and live fire exercises.

"They're sending six this year," Hardingham said in 2006. "They usually send two or four most years, but they're sending six because they've released more money for this training following this incident."

Likewise, the U.K. divisions of Total, Lindsey Oil, Conoco, SembCorp and BP have all been either represented at the annual school or received onsite training by WF&HC.

The Bronze commander ordered Hardingham to shift one of the key monitors to cooling the exterior of the tank in question and extinguish surrounding groundfires. Hardingham advised against it, noting that the new location would not be close enough to extinguish the fires being targeted. Also, it meant taking a key monitor, a trailer-mounted Ambassador 2X6 Gun capable of up to 6,000 gpm, out of action.

At that moment, the 2X6 was the most effective weapons at the firefighters' disposal, Hardingham said.

"Now these guys are surrounded almost 220 degrees by fire," he said. "If they knock it off (the 2X6), they've got nothing to fight those fires with. They could easily end up being totally surrounded 360 degrees by fire."

Hearing that, the Bronze commander ordered that the firefighters evacuate the entire site.

"It gave us a chance to have a rest and reassess exactly what we are going to do with this water which was still being knocked on and off on a regular basis," Hardingham said.

As the firefighters walked off the site, they saw 12 lines of six-inch hose along the terminal roadway, he said.

"Now all we had coming in on the site were three lines of six-inch hose, "Hardingham said. "I've asked many times where those other nine lines of 6-inch hose were going? To this day, I have never had an answer. Our immediate reaction was, 'Where the hell is this hose going?' We were really shocked."

Once the site was evacuated, a meeting of the officials in charge was held. Hardingham said he remained adamant about what was needed for success at Buncefield. "I argued that what we needed to do is be secure with our water supplies and decide whether to protect the unburned areas and let the rest of this facility burn, because if you continue to have the water turned on and off, you're wasting all the effort and the foam."

The decision was made to return to the site in two hours and concentrate on protecting the unburned tanks. Firefighters used water curtains to protect the tanks that could be saved, allowing the rest to burn.

"To be honest, at this point in the timeline, there wasn't a lot left to burn in some of them," Hardingham said.

Some of the tanks burning would have been difficult to extinguish under the best of conditions, he said. One of the last tanks tackled posed its own special problems.

"Anyone who has dealt with an internal floating roof tank knows they're buggers," Hardingham said. "We left this one. We couldn't extinguish it. It was burning out the vents and we had no way of extinguishing it with the other tanks burning. To make matters worse, it had pressure fires burning outside it."

Using an extended aerial ladder to gain a better view, he determined that the roof had split open and the tank was burning inside.

"We decided to let it burn itself out," Hardingham said. "It only had about 10 feet of product left in it. We put out the bund (containment dike) and tried to deal with the pressure fires."

Finally, one by one, the fires went out. On Dec. 11, the site held more than 9.2 million gallons of gasoline, diesel and aviation fuel. Fifty-nine hours later, almost one-third of this inventory was lost.

Strangely enough, Hardingham actually made it home to Leigh-On-Sea twice during the lengthy fire, only to be recalled to the scene. On one visit, he walked through the front door covered in grime from head to foot.

"My wife wanted to know why I was dirty," Hardingham said. "There were lots of firemen on the television and they were all clean."

In the future, Hardingham said, the U.K. needs to consider having plans in place to mobilize a team of experts with experience in petroleum and petrochemical firefighting when these emergencies occur.

"We have hostage negotiators and hijack teams who are trained especially for those jobs," Hardingham said. "Why not have experts for industrial emergencies?"

In particular, the team of about a dozen experts would train to take charge of storage tank fires.

"We don't need it for process fires because these are not long-term fires,"Hardingham said. "We need it for tank fires because these are the ones that do last for a while. It may be 12 hours before you start to attack it. So you've got long-term implications."

This team, trained to interact in industrial emergencies, should, in Hardingham's opinion, include members of the government, the Environmental Agency, municipal firefighters and industrial fire crews.

"This incident proves to me that you need expertise," Hardingham said. "What if these industrial firefighting teams with their fire chiefs and equipment had not been released by their management to attend or if they had been busy doing something else? Where would we have been?"

A letter from Roy Wilsher, HFRS Chief Fire Officer, published in Industrial FireWorld subsequent to the above feature, challenged the Hardingham account regarding Buncefield on several key issues. The majority of tank fires were extinguished within 36 hours of the "main foam attack starting over" with nine million gallons of product saved, Wilsher said.

He agreed that some reignitions had occurred and that some of the foam supply "was not up to scratch." However,the decision cited by Hardingham to evacuate the fire ground was not based on concern about a possible tank explosion, Wilsher said, but about a running fuel fire breaching the containment bund walls, threatening to release a large amount of water. Wilsher also stated that Hardingham was not the operations firefighting coordinator on site. Hardingham had no role in the command structure, he said.

In a reply to Wilsher, Hardingham stated again that he was initially asked to attend by the deputy prime minister's office as a technical advisor. Although he never held a command position at Buncefield, he did function as firefighting activities coordinator in conjunction with HFRS Bronze command.

"Williams Fire & Hazard Control submitted an invoice to HFRS for our charges in relation to my technical assistance and attendance which was paid promptly by HFRS," Hardingham said.

He also reaffirmed that the reason he was given for the evacuation was that the unignited tank might explode without immediate cooling water. Hardingham said he was certain that oil industry fire crews who attended would bear out his version of events.

An editorial that appeared in the June 2007 edition of the Joint Oil and Industry Forum (JOIFF) newsletter, The Catalyst, states that the forum had consulted members who attended the incident and confirmed that Hardingham "had a significant command role, actively directing firefighting operations and was a key industrial figure liaising between Hertfordshire Fire and RescueService operations firefighting coordinator and the incident commander, located at Bronze command."

Editor's note: This after-action review appeared in "Disasters Man-Made" by David White and Anton Riecher that was published in 2011.