Efforts to stop a California industrial disaster were on a "new trajectory" on Sunday, officials said, revealing that crews discovered a pressure-relieving crack in the tank behind a toxic chemical leak in Orange County, where 50,000 people remain evacuated.In a post to X, Orange County Fire Authority Interim Chief TJ McGovern said the discovery still needs validating, but if confirmed, it could alter the strategy as crews search for a solution to the crisis."With this new information, it could change our trajectory and our strategy to this event," he said. "Last night was a successful operation for this emerging incident."The crisis, entering its fourth day on Sunday, remained without a clear solution as a tank estimated to contain 7,000 gallons of methyl methacrylate continued to leak at GKN Aerospace in Garden Grove. OCFA Incident Commander and Division Chief Craig Covey said on Saturday that the temperature inside the tank was rising at a rate of about one degree per hour. That was contrary to the agency's thinking on Friday, just hours after the leak caused the first evacuation orders on Thursday night.When speaking to reporters on Sunday, California State Senator Tom Umberg, who represents the area, said the temperature read 100 degrees during Saturday night's operation, which is as high as the reading goes. He called the potential release of pressure "a good thing.""That may avoid the two concerns that we all had," he said. "One was an explosion, the other was a leak of liquid material vaporizing into a toxic fume, a toxic plume."