Analysis of Buncefield Explosion - Case Study Example

TABLE OF CONTENTS 1. Introduction……………………………………………………………… 2 2. Summary of the Buncefield Incident……………………………………... 6 3. Effects On The Surrounding Area Both During and After The Buncefield Event ………………………………………………... 7 4. Steps Of Redevelopment That Were Required For Reconstruction Of The Site………………………………………………………………………. 11 5. Summary Of The Key Findings Following The Official Investigation Into The Event…………………………………………………………………….. 13 6. Conclusion………………………………………………………………... 19 7. References 21 INTRODUCTION One of the most important aspects of construction technology is fire technology and the many fire disasters that occur regularly points to just how much this is the case. The UK has constantly been faced with fire tragedies over the years and with each tragedy, questions arise to what could have been done better with regards to the preventative measures. One such fire tragedy was the Buncefield incident which was such a major explosion that the effectiveness of these preventative measures was called into question. To understand what went wrong and how similar explosions can be prevented in the future, the following discussion analyzes the cause of the explosion; the effects on the environment; and the methods of redevelopment that can be used to redevelop such a contaminated piece of land. SUMMARY OF THE BUNCEFIELD INCIDENT The Buncefield tragedy happened on 11 December, 2005 when several explosions went off in the Buncefield Oil Storage Depot in Hertfordshire. According to Ceranna (2009, p. 491), great amounts of vapour emitted from the Buncefield site in line with loss of containment from pipe work or tanks. A large fire followed covering up 21 tanks that were on the site. Involved in the emergency response were the fire and police services with over 180 firefighters fighting the inferno with the use of 26 fire pumps and more than 700,000 liters of foam (Moore and Lakha, 2006, p. 171). The explosion was one of the largest in European history creating a tremor that measured 2.4 on the Richter scale and causing extensive damage affecting up to 2km from the site. Many homes were damaged. Even businesses were affected where 20 businesses that employed about 500 workers were ruined while the location of 60 other businesses that employed 3500 workers though not destroyed were badly damaged. In terms of human casualties, no deaths occurred though 60 people suffered from minor injuries. 2000 people were evacuated. Concerning the environmental effect of the explosion, there was significant pollution and great amounts of black smoke was discharged which spread dispersed far across Hertfordshire and beyond. In fact, the fire burned for several days and the devastation to the site was immense (New Forest Crime District Council, 2007). EFFECTS ON THE SURROUNDING AREA BOTH DURING AND AFTER THE BUNCEFIELD EVENT Despite being the largest explosion in pace- time Europe, the effects were surprisingly minimal. That said, there were considerable effects in terms of contamination of the land end environmental pollution. The fire was caused due to a spillage of 300 tonnes of petrol and this in itself is major pollution. The site inventory when the explosion occurred was more than 35 million liters of petrol, aviation fuel and diesel. About a third of the site inventory was lost having been consumed by the fire (New Forest Crime District Council, 2007). During the Buncefield explosion, widespread destruction was experienced on the site and large sections of Buncefield were destroyed. During this time, over 2000 homes were evacuated and the site was out of operation to allow the Health and Safety Executive and Environment Agency to monitor and investigate the area. There were twisted wrecks of the burnt fuel tanks left on site, 26 million litres of stored water was contaminated. According to the Environmental Agency (2009), there was contamination of groundwater beneath and up to 2km of the site by the fire-fighting foams used in fighting the fire and the hydrocarbons that had been emitted from the explosion itself. 800,000 litres of contaminated water from the Blackbird sewage treatment works leaked into the Colne which is a tributary of the Thames causing major concern. Despite this, the water contamination was contained and with time, the contamination reduced and was restricted to the immediate area near the depot.  The movement of this water contamination was fortunately contained. Nevertheless, an on-site monitoring borehole was set up by the oil companies in 2007 to help enhance understanding about the degree of the water contamination (Environment Agency, 2009). In terms of air pollution, reports concerning the results of the air quality showed that there was not any widespread air pollution on the ground during the incident. One such report, the 'Interim Review of Air Quality Aspects of the Buncefield Oil Depot Explosion' revealed that in spite of the magnitude of the explosion, the concentrations of pollutants on the ground-level were not far off from the concentrations that are usually present at that time of the year (Local Government Chronicle, 2006). They also reported that there was little public exposure to the plume created by the fire. In terms of the actual types of pollutants released, they included carbon monoxide, particulate matter, volatile organic compounds, polycyclic aromatic hydrocarbons, nitrogen oxides, hydrocarbons, dioxins and furans. Importantly, the concentrations of chemical contaminants like hydrocarbons or polycyclic aromatic compounds that one expects from such a major fire were low posing no major threat to the environment and public (Local Government Chronicle, 2006). Therefore, the air pollution at the site was minimal during and after the explosion. As for soil pollution, the Department for the Environment, Food, and Rural Affairs revealed that explosion did not cause much pollution to the soil or around the site (BBC News, 2006). Therefore, the soil conditions on the site were remarkably almost as good they were before the explosion. STEPS OF REDEVELOPMENT THAT WERE REQUIRED FOR RECONSTRUCTION OF THE SITE Following such a major explosion, redevelopment of the land into a commercial or residential property is challenging. Risk assessment is necessary and there are various steps that should be taken as part of the process or risk assessment and there are four main stages: hazard identification, hazard assessment, risk estimation and lastly, risk evaluation. It is these four stages that this discussion shall analyze. 1. Hazard identification: Under this first stage, a desk study shall be carried out. The desk study is a report detailing various aspects about the site including the following: previous land use; site history; physical characteristics such as the topography and geology; site location; site description, the intended site use; details about the storage tanks on the site together with details about their contents, leaks or spillages; details about discussions held with appropriate bodies; a walk over survey; the drainage on the site; photographs of the site; and a preliminary risk assessment among others. In addition, the contaminants of concern are identified s that it is known what the exact contaminants being combated are (Ryedale District Council, 2007, p. 1). 2. Hazard assessment: Under the second stage of, a conceptual site model is developed. A conceptual Model Site (CSM) is a model which shows in written or diagram form the various links existing between contaminants, receptors and pathways and is needed by not only the Environment Agency but also by the planning authorities who have to mitigate against hazards to human health. This CSM is updated continually since as the risk assessment process goes on, so does the information that is received over the course of later stages in the redevelopment process. 3. Risk estimation: this is a stage which is quite involving. Here, the ones involved in the process have to design and implement the site Investigations. In addition to this, quantitative and qualitative risk assessment is carried out to assess the risks to the environment, human health as well as to water (both ground and surface water with the use of models such as R&D 20, CLEA and SNIFFER. 4. Risk evaluation: this is the last stage and is one which basically entails evaluating the critical receptor and the risk management objectives as well as to determine the risk management techniques to be used (Doak 2004, p. 4). All these four steps are very important in analyzing the site in terms of the level of contamination, the hazard levels and also predicting the type of activities that can be carried out safely on the site. THE KEY FINDINGS FOLLOWING THE OFFICIAL INVESTIGATION INTO THE EVENT Since the Buncefield explosion was such a major incident, there were many questions as to the cause of the explosion as well as the parties responsible for it. An official investigation was therefore conducted to get to the bottom of the incident. The Health & Safety Executive (HSE) led the investigation. According to the report, the explosion was caused after the overflow of thousands of gallons of petrol from a storage tank following the break down of automatic monitoring systems. The writers of the report believed that a defective fuel gauge might have allowed petrol big enough to fill five swimming pools into tank 912 at the Hertfordshire depot from around 3 am to 6am the same day the explosion happened. The petrol began to flow out of vents on the top of the tank later transforming into flammable vapour cloud as it flowed down the tank’s side. The vapour cloud spread to about 8 hectares of the site by the time of its ignition which was possibly set of by a spark in an electrical generator or a fire pump house (Fickling, 2006). The investigation revealed that the fuel in the tank was likely surging at 890,000 liters an hour. Also, a misty white cloud was showed b CCTV footage at the site the spread from the tank for over 20 minutes before the explosion while witnesses revealed that this cloud was seven meters deep in certain areas. This shows that the security at the site was poor since this cloud spread for 20 minutes which is a long time in which the owners of the site could have prevented the explosion. In addition, according to Nissé (2006), the report by the HSE also revealed that the Buncefield oil storage site had been built using an outdated design that would not have been allowed under modern building and construction standards and regulations. There were grave defects to the design of Buncefield which made the explosion larger than it should have been. The same expert explained that the site was so overcrowded such that it was unable to handle the large amounts of extremely inflammable aviation fuel that went through it. In addition, the fuel tanks were grouped about three or four to a bund yet in other parts of Europe, sites never have in excess of two tanks to a bund pointing to the shocking overcrowding that was present at Buncefield. Another shocking revelation of the report is that both Total and the BPA who used the depot had agreed to safety reports with the HSE that require them to meet the terms of European regulations concerning the control of major hazards. In fact, the HSE had visited the site on 24 November, barely a month before the unfortunate incident. HSE approved of the site meaning that they felt that it conformed to international safety standards (Nissé, 2006). In summary, the key findings of the official investigation into the Buncefield investigation are that the fire was caused by an overflow of thousands of gallons of petrol from a storage tank following the break down of automatic monitoring systems. It was worsened by the lack of proper handling and the poor safety standards at the depot such as over crowding. CONCLUSIONS The Buncefield explosion was the largest in peacetime European history and though there were no casualties, the financial damage was great. Fortunately, the environmental damage was minimal with low levels of air, water and soil pollution being reported by environmental and government bodies that investigated the effects. This is positive news for reconstruction/ redevelopment efforts since the level of contamination was low. To prevent such a major explosion from re occurring, the government should enforce strict safety regulations in similar depots, ensuring that all comply with international safety and building standards to ensure that overcrowding is prevented and that fuel is stored safely. If this is accomplished, the chances of another explosion of that nature will have been reduced considerably ensuring the safety and assurance of all citizens against avoidable fires such as this one. REFERENCES BBC News. 2006. Buncefield explosion: One year on. Retrieved 13th January, 2010 from http://news.bbc.co.uk/2/hi/uk_news/6181626.stm Ceranna, L. 2009. The Buncefield explosion: a benchmark for infrasound analysis across Central Europe. Geophysical Journal International Vol 177 (2): 491 - 508 Doak, Malcolm. 2004. Contaminated Land and Risk Assessment: The Basics Necessary Steps Prior To Remediation and Development. Environmental Protection Agency. http://www.epa.ie/downloads/advice/licensee/IAH%20Tullamore%202004%20NDP%20Paper(final).pdf Environment Agency. 2009. Buncefield fuel depot. Retrieved 13th January, 2010 from http://www.environment-agency.gov.uk/homeandleisure/pollution/water/89141.aspx Fickling, David. 2006. Faulty fuel gauge caused Buncefield explosion. The Guardian. Retrieved 13th January, 2010 from http://www.guardian.co.uk/uk/2006/may/09/buncefield.davidfickling Local Government Chronicle. 2006. Buncefield Air Quality Findings Published. Retrieved 14th January, 2010 from http://www.lgcplus.com/news/buncefield-air-quality-findings-published/508408.article New Forest Crime District Council. 2007. Crime and Disorder Review Panel – 20 November 2007. Retrieved 13th January, 2010 from http://www.newforest.gov.uk/committeedocs/cdrp/CDR03240.pdf Moore, Tony and Lakha, Raj. 2006. Tolley's handbook of disaster and emergency Management. Massachusetts: Elsevier Ltd. Nissé, Jason. 2006. HSE could face massive claims over Buncefield explosion: Environmental protection expert tells 'IoS' that depot, built in 1968, did not meet current design standards. The Independent. Retrieved 12th January, 2010 from http://www.independent.co.uk/news/business/news/hse-could-face-massive-claims-over-buncefield-explosion-519878.html Ryedale District Council. 2007. Developing potentially contaminated land: A guide for Developers. Retrieved 14th January, 2010 from http://www.ryedale.gov.uk/pdf/Developing_%20potentially_contaminated_landapril07.pdf Read More