Enemalta inquiry uncovers cause of 'rotten cabbage' odours in 2009

Enemalta Corporation has kept under wraps an internal investigation it has been conducting on a case of theft, which inadvertently discovered the cause of an incident two years ago that resulted in a foul smell of gas reported across Malta.

The Enemalta board of inquiry was told that on 4 September 2009, 10 barrels each containing 45 gallons of methyl mercaptan were allegedly burnt in the limits of Mġarr. The activity was carried out by a number of Enemalta employees assisted by a fire engine belonging to Enemalta’s fire section.

One of the reasons for the inexplicable, foul smell that resulted is that methanethiol is a colourless gas that smells like rotten cabbage. But it is also found in humans and animals, and disposed of through animal feces. It occurs naturally in cheese, and is one of the chemicals responsible for bad breath and flatulence.

The incidents had provoked reports from various localities including San Gwann, Valletta, Birkirkara, Rabat, Iklin and Imsida about the persisting gas foul smell. But 24 months down the line, Enemalta has never made any formal declarations on the cause of the smell.

Enemalta had then said that its technical staff had investigated all the corporation’s installations, visited towns using gas detectors, and also visited “a site where Mercaptan was deposited in the morning” but only said it had established there was no danger.

Mercaptan is the harmless, non-toxic chemical that is added to natural gas to make it easier to detect in case of a leak.

Labour MP Joe Mizzi, who has been pursuing answers on the cause of the smell, said he found the details to be “shocking”.

“A few days ago I received the same information and immediately I saw a pattern. Why is it that every time that a major mishap takes place in Enemalta, the information is kept under wraps?

“The Prime Minister needs to launch an independent enquiry on this case. It is not acceptable that serious offences like this are sealed away from public scrutiny,” Mizzi said.

Mizzi also said that on various occasions, Enemalta has adopted a policy not to be truthful about such events. “Even through finance minister Tonio Fenech, Enemalta lied to House of Parliament when the Marsa precipitators were switched off. Fenech went on record saying that the main reason was a technical failure. But then it transpired that the precipitators were off after MEPA’s instructions.”

Earlier in July 2009, Enemalta had to seal a container which leaked Mercaptan at its facility in Corradino after a valve was stolen.

Mercaptan is added to gas cylinders because of its distinctive smell to help users detect any leaks since Liquid Petroleum Gas is highly combustible but is odorless.

Methyl mercaptan has raised eyebrows through the international community with various leak cases reported, including a major case in 2009 in San Francisco Bay Area. In November of that year a gas supplier injected too much methanethiol into supply lines. Thousands of households flooded the emergency support systems reporting the leaks.