A faulty, outdated valve apparently caused the huge blast Nov. 11 at a Petroleos Mexicanos gasoline tank farm on the outskirts of Mexico City that killed four people and injured 19 others.
It was the latest in a string of mishaps for the troubled state petroleum company, which has led it to reevaluate its safety procedures and try to restore its image, critical for a company that oversees the economic lifeblood of the country.
Pemex General Director Adrian Lajous last week told Mexico's Congress that an inspection conducted in July detected that the metal in the valve did not meet Pemex specifications.
He could not say why the valve, installed in 1977, was not changed at that time. Pemex is checking other installations for similar valves.
Deadly blast
Pemex is again the target of public and official ire after the Nov. 11 explosion at its San Juanico refined products storage complex in the densely populated suburb a few minutes from the nation's capital (OGJ, Nov. 25, Newsletter).
About 100,000 bbl of leaded and unleaded gasoline burned out of control for more than 36 hr, destroying two of six storage tanks. More than 5,000 people were evacuated from residential areas near San Juanico. Pemex estimates that it lost $5 million worth of product.
In addition to the explosion at San Juanico, Pemex has had a spate of high-profile accidents at installations around the nation.
In July, a natural gas processing complex in the southern state of Chiapas exploded-taking off line more than a third of Pemex's natural gas production capacity.
Taking the heat
Earlier in the week, Lajous acknowledged Pemex had a safety problem: "In terms of effectiveness of our maintenance, it's likely that we are not clearly in line with standards that prevail in other countries around the world."
After the San Juanico explosion, Pemex said it will launch a 3-year program to develop risk assessment and response plans, bring facilities up to international safety standards, and conduct emergency preparedness exercises for communities near its facilities.
Oil Watch Mexico Director Sylvia Whizar said Pemex must instill a new "safety ethic" in addition to any technological or structural changes.
"Accidents involving Pemex facilities occur much more frequently and are more severe than those involving similar businesses in other countries," Whizar said. Pemex's budget is two-thirds of what is recommended internationally, she charged.
Lajous contends Pemex's budget is not the issue, however, because 20% of Pemex spending in 1996 has been dedicated to maintenance: "We are in the process of transition from a technology where there are still many manual controls to completely automated technology."
Mounting criticism
During the Nov. 19 hearing before the joint committee of Congress, federal deputy Ifgenia Martinez, a frequent critic of the oil monopoly, told Lajous that Pemex's concepts of safety and security should be similar to those followed by airlines.
While the San Juanico complex was on fire, the head of the Mexico City civil defense department called on Pemex to relocate the San Juanico facility to a safer location away from urban areas. Pemex officials rejected such a move, saying that the alternative of trucking refined products over a great distance would be more dangerous to communities.
The main opposition party, Democratic Revolutionary Party, said Pemex's top officials should be tried for alleged criminal negligence and corruption because of accidents at San Juanico and other Pemex facilities.
On Nov. 21, 1984, an explosion at the San Juanico complex sent a shock wave that could be felt throughout a large portion of Mexico City. More than 500 people died in the accident.
Since then, the facility has been downsized considerably but is still in use. In 1990, an underground pipeline exploded at San Juanico, causing damage but no loss of life.
Urban facilities
Pemex has three storage complexes in the Valley of Mexico, which includes Mexico City and the states of Mexico and Morelos, with a combined capacity of about 8 million l. of refined products. An additional 3,000 small and medium-sized tanks are located near industrial plants.
Environmentalist groups are urging Pemex to reduce the size of the three storage areas and surround them with a buffer zone. In many cases, such as in San Juanico, residential areas are now abutting Pemex facilities.
Lajous agreed that urban sprawl should be contained. He told Congress that local governments cannot let people build homes and other structures next to Pemex facilities or over its pipelines.
Environmentalists also said that firefighters must be trained to respond appropriately to petroleum fires. Initially, municipal firefighters tried to douse the flames with water, which helped spread the blaze to other areas. One of the four victims was a town fireman.
Copyright 1996 Oil & Gas Journal. All Rights Reserved.
