But the plant, part of the largest refinery complex in Venezuela, has from time to time spewed contaminants into the bay and the adjoining Caribbean Sea, threatening the livelihood of families living in this poor fishing village of several thousand on the country’s northwest coast.

With each spill — scores of them over the past three decades, residents say — fishermen have been forced to suspend their work as plumes of contaminants turned the water’s surface into a shimmering toxic kaleidoscope, poisoned fish and waterfowl, killed mangroves and soiled the town’s beaches.

The fishermen and their families have been able to do little, as if trapped in the worst of forced marriages, the population lashed to the refinery by the bay they share.

Most recently, a storage tank overflowed in heavy rain last October, dumping thousands of gallons of refinery slop into the bay. Dead fish washed ashore in Amuay, and dozens of pelicans were killed. Fishermen who worked the bay could not fish there for more than a month, leaving them in a financially perilous situation amid soaring inflation and a national economy in free fall.