MOSS LANDING, Calif.—At dusk on Jan. 16, rancher Brad Beach was checking on his small herd of Texas Longhorn cattle—a majestic bull named Tex, two cows, and three calves—grazing about two miles inland from California’s central coastline.

Beach saw smoke blowing from the coast, where two towers marked the distinctive silhouette of an energy plant. Shortly after leaving the herd, he noticed that a massive fire had broken out at the plant and came back to get his cattle, only to be turned away by the California Highway Patrol, which had the area on lockdown as residents were evacuating.