Part of the Qajjenza area in Birzebbuga yesterday morning was stinking horribly after a leak developed at the Enemalta Gas Depot, forcing the evacuation of dozens of workers and nearby residents.
The accident took place at around 6.50am when a gas bottle distribution truck hit a 200-litre (45-gallon) tank which contained the toxic chemical ethyl mercaptan, also known as ethanethiol, a corporation statement said later.
The chemical is added to the odourless Liquefied Petroleum Gas (LPG) used in homes as a safety measure to indicate potential leaks. Ethanethiol gives off a persistent and unpleasant odour of skunk. It is stored in a liquefied state, which is very flammable, and evaporates easily. In its evaporated form and under certain conditions, ethanethiol can be explosive. The chemical is also highly toxic and can cause dizziness, nausea, unconsciousness and irritation of the skin and eyes.
The truck hit the storage barrel and caused a crack. The Civil Protection Department (CPD) was immediately alerted, both by the plant workers as well as by the neighbouring residents.
Plant operations were halted right away and the corporation ordered a precautionary evacuation of the site while the tank was temporarily patched.
The police cordoned off the area and evacuated the workers until the arrival of the CPD officers, who asked nearby residents to close their doors and windows, switch off their air conditioners and electrical equipment, evacuate the area and avoid lighting any fire.
The Enemalta Fire Fighting Section manned a tank-to-tank transfer using explosive-proof pumps, which took about an hour-and-a-half to complete, while CPD members cooled the tank down in order to prevent it from heating up and catching fire.
Occupational Health and Safety Authority (OHSA) inspectors have now cleared the plant as safe and bottling production recommenced at 11.30am, the corporation said.
Speaking to this newspaper, CPD director Peter Cordina said all those involved had to work really fast because of the concentrated amount and intense smell of the ethanethiol.
The gas depot at Qajjenza was built in 1959 and its current storage capacity is of 2,300 metric tons of LPG and 200 metric tons of propane. Enemalta had proposed the relocation of the plant to ix-Xoqqiet, limits of Benghajsa, Birzebbuga. The Malta Environment and Planning Authority issued the permit for the relocation on 1 February 2007.
Birzebbuga mayor Joseph Farrugia said this incident was the latest sign of the danger Qajjenza residents have to live with. He called on the government to speed up the relocation of the plant to Xoqqiet and encourage the prospective new owners of the corporation’s petroleum division to start investing in the new plant as soon as possible.