UPDATE 1-Cost-cutting factor in Citgo refinery fire-sources

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By Erwin Seba

CORPUS CHRISTI, Texas, July 23 (Reuters) - Deferred repairs aimed at reducing costs may have played a role in in a fire last Sunday at Citgo Petroleum Corp's Corpus Christi, Texas, refinery which seriously wounded one worker, according to sources familiar with events leading to the blaze.

U.S. refiners have been putting off repairs and routine maintenance to cut costs since margins began sliding in mid-2008 as the recession hit nationwide fuel demand.

The fire in the plant's alkylation unit came after a pipeline failure triggered a vapor cloud, the sources said.

"There are massive lists of items needing repair that have been put off," said a source familiar with refinery operations.

"We don't have any information as to how the fire developed," said Larry Elizondo, a spokesman for Citgo, the U.S. refining and marketing subsidiary of Venezuela's state-owned oil company, PDVSA.

"All I can tell you is what I've already provided," he said.

One worker from the Citgo refinery, Gabriel Alvarado, 34, has undergone two surgeries for severe burns that extend over 60 percent of his body. He is being treated at the burn unit in Brooke Army Medical Center in San Antonio.