Los Alfaques disaster

The Los Alfaques disaster was a road tanker explosion that occurred near a holiday campsite on Tuesday 11 July 1978 in Alcanar, Spain. The exploding truck, which was carrying 23 tons of highly flammable liquefied propylene, killed 215 people and severely burned 200 more. Several individuals from the company that owned the vehicle were prosecuted for criminal negligence. The accident resulted in new legislation in Spain, restricting the transit of vehicles carrying dangerous cargo through populated areas to night time only.

Most of the victims were holidaymakers from Germany and other European countries who were staying at the Los Alfaques seaside campground. The site, which is located at km 159 on the N-340 national road, is 2 km south of the town of Sant Carles de la Ràpita.

Background
The campsite of Los Alfaques (Spanish for "the sandbanks") is triangular-shaped and wedged between the beach and the N-340 coastal national road. It is about 2 km south of the nearest township, Sant Carles de la Ràpita, although it belongs to the territory of the Alcanar municipality. When the accident occurred, it was 200 m in length and 10,000 m2 in area. From north to south, it tapered from about 100 m down to 30 m wide. Separating the campsite from the road was a brick wall with a concrete foundation. The campsite's legal capacity was 260 people. However, on the day of the accident, some 800 people were staying on the original grounds and on two new undeclared extensions; luckily, not all occupants were at the premises at the time.

The truck involved in the accident consisted of a Pegaso tractor unit and a Fruehauf semi-trailer tanker. It was owned by Cisternas Reunidas S.A. and on the day of the accident was driven by 50-year-old Francisco Imbernón Villena. The trailer was manufactured in 1973. Its maximum capacity was 45 m3 with a maximum allowed mass of 19.35 tons (at 8 bar and 4 °C).

Loading and departure
At 10:15 am, the driver arrived at the state-owned refinery, located at La Pobla de Mafumet, 9 km north of Tarragona, to be loaded with liquefied propylene for another state-owned company, Paular (now Repsol), in Puertollano. At 12:05 pm the fully-laden truck left the refinery carrying 23.47 MT of propylene, which was more than 4 tons over the maximum design load for the tanker (i.e., 19.35 MT). Thus, the tank was nearly hydraulically full of liquid, with minimal ullage space.

The tanker drivers were under instructions to take the smaller N-340 national road instead of the A-7. In the late 1970s, the N-340 was still a narrow and winding coastal road that passed directly through several densely populated urban areas.

Explosion
By 2:35 pm the truck was driving past the Los Alfaques campsite, after travelling 102 km from the ENPETROL refinery. The time is known because the driver's watch –which was found still attached to his burnt wrist– had stopped at 2:36 pm. The tightly packed campsite was crowded with nearly 1,000 holidaymakers, many from Germany, in trailers and tents.

During the journey, solar radiation and ambient temperature heated the liquefied gas from its initial conditions. Under normal circumstances, the presence of ullage gas vapors would have meant an increase in pressure well within the mechanical limits of the tank. However, the tank was hydraulically full, which meant that the liquid had no room left to thermally expand. This resulted in the tank walls being stressed over their design capacity.

According to some reports from surviving witnesses, the tanker was already leaking liquefied gas while passing by the campsite. Some witnesses thought they heard a loud bang that preceded the leak. The bang might have been caused by a blown tire, which caused the truck to swerve and crash into the wall separating the campsite from the roadside (possibly overturning in the process). Others argue that there was no mechanical failure or traffic accident before the loss of containment, with the overstressed pressure vessel failing at a weak point.

Within seconds highly flammable propylene started flashing out of the ruptured tank and formed a white cloud that drifted into the campsite and towards a discothèque to the northeast. According to some reports, numerous intrigued campers approached the cloud with curiosity as it continued to spread. Eventually it became so dense that many were unable to see the tanker. Within moments of the cloud reaching the discothèque, it ignited into a flash fire that quickly returned to the source of the leak thus causing the weakened tanker to explode. This generated a massive boiling-liquid expanding-vapor explosion (BLEVE), whereby the entire content of the tank car vaporized and burnt almost instantly in a fireball with a diameter estimated between 40–60 m and 180 m, resulting in tremendous levels of thermal radiation, as well as a significant blast wave. Other reports suggest that external fires did not contribute to the onset of the BLEVE, with the pressure vessel having BLEVE'd as a consequence of the tank walls being weakened by the thermal expansion of the liquid propylene, and the resulting expanding-vapour cloud catching fire only moments after its release.

The fire destroyed everything –cars, trailers and buildings– within a 90 m radius, charred everything within a 300 m radius, gutting over 90% of the main camping area. The 400 m2 discothèque to the northeast, which was later determined to be the likely source of the ignition, was also razed, killing all the staff members inside. Additionally, 34 vehicles and 21 tents were burnt out, a restaurant partially collapsed, and the tanker truck was broken into three main pieces. The blast effects of the BLEVE were comparatively minor, although there was at least one secondary confined explosion inside the discothèque buildings. The truck tractor was broken into four pieces. Two-thirds of the tank flew north-west, landed about 150 m away and then slid coming to rest against the wall of a restaurant, 300 m from the starting point. The middle section was flung about 100 m into the campsite.

Emergency response
The explosion and fireball instantly killed 158 people, including the truck driver. Victims were seen with their hair and clothing on fire, fleeing into the sea in an attempt to put out the flames. In the first 45 minutes after the disaster, the wounded were removed in an uncoordinated fashion with the help of other survivors using their own cars and vans. Locals also provided help and took the wounded to the hospitals. Ambulances and other emergency forces gradually arrived. The first ambulance came at 2.45 pm from a Shell oil drilling site at San Carles. Municipal ambulances arrived at 3.05 pm and the fire brigade at about 3.30 pm. The Civil Guard and the armed forces searched the devastated camp for survivors. It took three hours until the last of the wounded were removed and taken to hospital.

The burning tanker blocked the road, dividing the injured into two groups, one being taken northwards and the other southwards. On the road to the north, the injured received adequate medical care, once they had reached either the hospitals at Amposta or at Tortosa. At this stage, the final destination of 58 severely burned patients was the Francisco Franco Hospital in Barcelona. 82 severely burned patients were taken south to the in Valencia. In most cases no medical steps of any importance were taken during the journey. Several of the injured developed severe shock on the journey and had no measurable blood pressure on arrival. Many of the patients had burns covering more than 90% of their bodies, and most of them died during the following days. Contributing to the high mortality figure was the inappropriate medical care given en route to the hospital, especially for the wounded that were driven south towards Valencia.

In the week following the disaster, the patients from France, Germany, Belgium and the Netherlands were evacuated to their own countries.

Victims
More than 300 people were wounded, some of them severely. Initially 217 people died directly from the explosion (four Spaniards including the driver; all the others were foreign nationals), while the total number of people who died in the following months as a result of their injuries rose to at least 270. The official figure for the number of victims is 215.

Many of the victims were burned beyond recognition. Identification was difficult, as most of them were wearing only swimming suits, and the administration building where their documents were stored was destroyed in the explosion. There was no DNA test available at that time. As a result of the work done by the forensic teams from the tourists' home countries, all victims were eventually identified.

Seven of the victims remained unidentified until some time later, and they were interred at the cemetery of Tortosa. The bodies of a French family, consisting of a couple and their two children, were returned to France some years later, after compensation had been settled. The bodies of another family of three originating from Colombia were never sent home, and they remain the only foreigners to be interred at the cemetery of Tortosa along with local victims.

Inquiry
Following the accident, Cisternas Reunidas accepted responsibility for the disaster, but denied any order or prohibition to the drivers to use the motorway instead of the national road, claiming that it was the driver who chose which road to take. Later, some workers at the Tarragona plant stated they heard the driver heatedly arguing with someone on the phone and demanding money for the motorway toll. ENPETROL initially declined any responsibility, claiming that the delivery of the cargo was the carrier's responsibility, and they had not received any complaint.

The official inquiry determined that the truck had been severely overloaded, and also lacked emergency pressure relief valves, which would have helped prevent the BLEVE. However, these valves were no longer mandatory in 1978 as they previously had been. The truck was due for an inspection check-over in 1980, and it had passed the previous inspection.

The tank container was manufactured on 13 December 1973 by a workshop from Bilbao, and at that time it did not meet the requirements for carrying flammable liquids, since it lacked emergency pressure release valves. Therefore, the tank had been used to carry other substances, some of which were highly corrosive. Tests on the remnants of the steel tank revealed microscopic stress cracks consistent with corrosion caused by previous loads of improperly pressurized anhydrous ammonia. Possibly compounded by the effect of an external impact that caused additional structural damage, these factors likely led to the almost instantaneous rupture of the tank when the flames flashed back into the tanker. Even without safety valves, a structurally sound and properly filled tanker should have been able to maintain structural integrity in a fire long enough to at least allow nearby people to escape.

The inquiry also revealed that overloading of tankers was common practice at ENPETROL facilities. The Tarragona plant lacked either a meter to measure the amount of gas dispensed or an automatic shut-off device to prevent overfilling, and consequently most tanks were consistently overloaded. The driver was neither informed of the overloading, nor about the type and class of the cargo, and there was no means for him to check the pressure level of the tank before he departed or to monitor it in transit. He had not attended the hazmat training program for drivers of vehicles carrying dangerous goods, because the company considered his experience of 20 years as a truck driver to be sufficient. The inquiry also determined that, between 3 January and 7 July of that year, 32 tanks driven by several different individuals left the Tarragona refinery overloaded.

Legacy
After the tragedy, daytime transit of populated areas by vehicles carrying dangerous cargo was prohibited.

In 1982, four employees of ENPETROL and two of Cisternas Reunidas were convicted of criminal negligence, and were sentenced to prison for between one and four years. Later, four of them were released after appealing the Court's decision, and all prison sentences were suspended or reduced. The two companies paid an equivalent of €13.23 million (not allowing for inflation) as compensation to the victims.

Six months after the tragedy, the completely renovated campsite was reopened to tourists and Los Alfaques continued in operation.

In 2012 the owners of the still-operating campsite sought relief through Spanish courts under the newly approved "Right to Be Forgotten" Act passed by Spain, arguing that Google Search results were unfairly weighted towards the 1978 disaster and were driving away their business. The campsite owners protested that even 30 years after the disaster, the top 12 Google search results for "Los Alfaques" still focused on the 1978 tragedy, including many gruesome thumbnails of burnt human remains, stacked caskets and coroner procedures during cleanup of the campground. The trial was dismissed, with the plaintiffs being informed that they would need to pursue a U.S. lawsuit against Google.

In popular culture
The accident is featured in the 2007 German film Day of Disaster (original title: Tarragona – Ein Paradies in Flammen, also known as Tarragona: Paradise on Fire), directed by Peter Keglevic. The film is loosely based on real facts, and contains blunders and factual errors, such as cars or registration plates which could only have appeared years later, or the driver spending the night before at home with the already (over)loaded tanker parked in front of his house.