Buncefield fire


The Buncefield fire was a major fire at an oil storage facility that started at 06:01 UTC on Sunday 11 December 2005 at the Hertfordshire Oil Storage Terminal, located near the M1 motorway, Hemel Hempstead, in Hertfordshire, England. The terminal was the fifth largest oil-products storage depot in the United Kingdom, with a capacity of about of fuel. The terminal is owned by Total UK Limited and Texaco.
The first and largest explosion occurred near tank 912, which led to further explosions which eventually overwhelmed 20 large storage tanks.
The emergency services announced a major emergency at 06:08 and a firefighting effort began. The cause of the explosion was a fuel-air explosion in a vapour cloud of evaporated leaking petrol. The British Geological Survey monitored the event, which measured 2.4 on the Richter scale.
News reports described the incident as the biggest of its kind in peacetime Europe and certainly the biggest such explosion in the United Kingdom since the 1974 Flixborough disaster. The flames had been extinguished by the afternoon of 13 December 2005. However, one storage tank reignited that evening, which firefighters left to burn rather than attempting to extinguish it again.
The Health Protection Agency and the Major Incident Investigation Board provided advice to prevent incidents such as these in the future. The primary need is for safety measures to be in place to prevent fuel escaping the tanks in which it is stored. Added safety measures are needed for when fuel does escape, mainly to prevent it forming a flammable vapour and stop pollutants from poisoning the environment.

Incident

Explosion and fire

The first and largest explosion occurred at 06:01 UTC on Sunday, 11 December 2005 near container 912. Further explosions followed which eventually overwhelmed 20 large storage tanks.
From all accounts, it seems to have been an unconfined vapour cloud explosion of unusually high strengthalso known as a fuel-air explosion. Because of an inversion layer, the explosions were heard up to away; there were reports that they were audible in Belgium, France, and the Netherlands.
The British Geological Survey monitored the event, which measured 2.4 on the Richter scale. It was reported that people were woken in south London, and as far west as Wokingham about away, where in its southern suburb, Finchampstead, numerous people felt the shockwave after the initial explosion. Subsequent explosions occurred at 06:27 and 06:28.
Witnesses many miles from the terminal observed flames hundreds of feet high; the smoke cloud was visible from space, and from as far north as Lincolnshire about away. Damage from the blasts included broken windows at various buildings including the Holy Trinity church and Leverstock Green School, blown-in or warped front doors, and an entire wall being removed from a warehouse more than from the site. Buildings in neighbouring St Albans also suffered; Townsend School had serious blast damage, and was subsequently closed for repair work and a window was blown out of St Albans Abbey about away.
Several nearby office blocks were hit so badly that almost every window, front and back, was blown in as the explosion ripped through them. The timing of the explosion before work hours possibly prevented additional casualties. Reports also indicated that cars in nearby streets caught fire. The roof of at least one house was blown off. Buildings in the vicinity were evacuated by police, not only because of the smoke and possibility of more explosions, but because of the danger of structural damage making the buildings unstable.
There were 43 reported injuries. Two people were hospitalized, one in Watford General Hospital, with breathing difficulties, and another in Hemel Hempstead Hospital, although they were not in a life-threatening condition. No one was killed in the incident. All members of staff from the terminal were accounted for.
Hertfordshire police and fire services and the member of parliament for the area, Mike Penning, said that there were seven fuel tanks on the site which, as of 14:00 on 12 December, had not been affected. These tanks were at risk of exploding if the fire were to spread.

Tackling the blaze

The emergency services announced a major emergency at 06:08 and a tremendous firefighting effort began. At peak times this effort consisted of 25 fire engines, 20 support vehicles and 180 fire fighters.
Around 150 firefighters were called immediately to the incident, and began tackling the blaze at 08:20 on the morning of 11 December, putting in containment measures before applying a large quantity of foam. The incident occurred close to junction 8 of the M1 motorway, which led to its closure and the setting up of a public exclusion area. It was estimated that this incident would be the largest "single-seat" fire in the world ever to be fought by a fire brigade, and foam supplies from sites all over the UK were drawn upon.
Plans had been in place to start using foam at midnight on 11 December, but were delayed by last-minute concerns over possible pollution of local rivers and underlying water sources. Six high volume pumps were used to extract of water per minute per secondfrom a reservoir from the fire, with six more high-volume pumps deployed at various locations to serve as boosters. Thirty-two thousand litres of fire fighting foam per minute were directed against the fire for just over four hours, after which the pumping rate was reduced. Half of the 20 individual fires were reported extinguished by midday.
By 16:30 on Monday 12 December, it was reported that a further two tank fires had been extinguished, but that one of the tanks extinguished earlier had ruptured and re-ignited, and was now threatening to cause the explosion of an adjacent tank. This led to the M1 motorway being closed again; the public exclusion area was widened, and firefighters were temporarily withdrawn until the risk posed by the threatened tank could be assessed.
Firefighting operations were resumed at about 20:00, and it was anticipated that all fires could be extinguished during the night. Further damage occurred to one of the storage tanks in the early hours of Tuesday morning, causing firefighters to be withdrawn once again, but operations resumed at 08:30. By midday on 13 December, all but three fires had been extinguished, although the largest tank was still burning. Bronze commandoperations on the groundwas visited by the Bishop of St Albans, the local vicar, and the industrial chaplain supporting the fire crews, to see how they were coping.
Firefighters were confident that the remaining fires could be extinguished during the day on Tuesday, 13 December. The smoke plume had been considerably reduced and was more grey, indicating the amount of vapourised water now combining with the smoke. It was reported at 16:45 that all tank fires had been extinguished, although some smaller fires persisted. 75% of firefighters for Hertfordshire were involved in fighting the fire, supported by 16 other brigades. The entire gold command operation, involving many agencies as well as all the emergency services, was run from Hertfordshire Constabulary's headquarters in Welwyn Garden City, some distance from the fire.
A further fire broke out during the early morning of 14 December. Firefighters were of the view that extinguishing it would leave the risk of petroleum vapour re-igniting or exploding, so it would be better to allow the fire, which was well contained, to burn itself out. Hertfordshire Fire Service's deputy chief Mark Yates stated that escaping petroleum vapour was the most likely cause of the original explosion and fire.

Smoke cloud

The black smoke cloud, which was visible from satellite photographs, drifted at a high altitude, around, towards Reading and Swindon, and could be seen across much of South East England.
The small particles in the smoke contained hydrocarbons, which can be an irritant but have a low toxicity and were not expected to cause any long-term harm. The Met Office issued warnings that the smoke in the atmosphere could come down in rainfall during the night of 11 December.
The fire resulted in 244 people requiring medical aidmainly on the first day of the fire. From those 117 had symptoms attributable to the incident, of whom 38 were members of the public. The majority of those visiting hospitals were from the rescue services and attended for precautionary check ups. Most of them had no symptoms, except for 63 emergency workers who suffered respiratory complaints, of which half were sore throats.
For the first two days of the fire, the high thermal energy made the plume highly buoyant; this, together with settled weather conditions, allowed the plume to rise to a great height with little cross-mixing. When the fire was reduced in intensity it was reported to be possible that the plume would be less buoyant and that ground-level smoke concentrations could then rise significantly. By 12 December, it was reported that the smoke cloud had reached northern France; it was expected to arrive in northern Spain by the weekend.
To investigate the smoke cloud the Facility for Airborne Atmospheric Measurements, a research aircraft operated jointly by NERC and the Met Office, made two flights on 12 and 13 December. In the first flight the edge of the plume was followed along the south coast of England. Carbon monoxide, nitrogen oxides and ozone concentrations were found to be low with soot particles being the major component in the cloud. The second flight went into the centre of the plume to obtain data to help forecasting and emergency teams.

Reactions and response

Evacuations and closures

Hundreds of homes in the Hemel Hempstead area were evacuated, and about 2,000 people had to find alternative accommodation; emergency services asked residents of the smoke-affected areas to close their windows and doors and to stay inside.
Hertfordshire Constabulary advised people who had houses with smashed windows to seek refuge with friends or family nearby if possible. Some people whose homes were damaged by the blast were placed in hotels, while others stayed in a nearby shopping centre. Total, the operator of the Buncefield depot, set up a helpline for people whose properties had been damaged by the explosion, and called in local authorities and the Salvation Army to provide accommodation or other help.
Concerns for public safety resulted in about 227 schools, libraries, and other public buildings across Hertfordshire and Buckinghamshire closing on 12 and 13 December. Police and local authorities advised residents to consult the Hertfordshire Direct website for up-to-date information.
Seventy-eight schools in Luton borough were closed on 13 December, along with a limited number of schools in Bedfordshire, on the advice of Hertfordshire's Health Protection Agency that all schools within a radius of the incident site should be closed because of concerns surrounding the effect of the smoke plume on children's health. Schools reopened as normal on 14 December.