Ammonia Leak In Mexico Pemex Pipeline Kills 7 In Oaxaca

Four more Pemex workers have died after a blast at one of the state oil company's refineries in the southern state of Oaxaca, taking the death toll up to seven. The explosion happened on Tuesday, as workers performed construction on what the Associated Press described as a highway expansion project. The government of Oaxaca said machinery operated by a private company hit a pipeline carrying ammonia to a petrochemical plant, causing the leak which triggered the explosion. Some 1,200 people were evacuated from houses in the area, and the Mexican military cordoned off the immediate area where the disaster occurred. Pemex said that as a security measure, the flow of the gas through the pipes was immediately cut off.

The news comes exactly a month after seven people were injured by an explosion as they attempted to illegally tap a pipeline belonging to Pemex in Tonanitla, a town about 25 miles north of the capital of Mexico City. The company is a frequent target of illegal pipeline taps - Carlos Morales, head of Pemex's exploration and production arm, told Reuters in June that it loses as much as 5,000 to 10,000 barrels of crude oil per day. "The thefts target gasoline, diesel and crude ... they vary all the time but without a doubt they have a major impact on the (Pemex) budget. Each year fuel theft in Mexico has increased 30 percent," Morales said.

And in February of this year, Pemex suffered the huge setback in what had been a steadily improving safety track record when an explosion ripped through four floors of its administrative headquarters in Mexico City, jolting the 54-story Pemex Executive Tower next door. 33 workers were killed in that accident and 120 injured. Workers were in the midst of changing shifts at the time it went off, a coincidence which undoubtedly increased the toll of casualties. It was the largest single-day death toll the company had seen in over a decade.

Pemex has been state-owned since 1938, when the assets of Standard Oil and Royal Dutch Shell were seized and petroleum deposits nationalized after the companies refused to comply with a judge's ruling in a dispute between them and the Mexican government. But in the face of lagging efficiency and drying-up petroleum reserves which could see Mexico become a net importer of oil by 2020, it will likely undergo a major overhaul soon.

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