EUREKA, Utah (AP) – A Utah agency is working to seal thousands of old mines across the state after people have died in rock falls and all-terrain-vehicle crashes and from poisonous air in the past few decades. The American West holds hundreds of thousands of abandoned mines, many of them potentially dangerous. In Utah alone, state figures show there have been 11 deaths since 1982 and more than 40 injuries, including people who fell into old mines and others who entered them to explore. The openings were thrown into the spotlight this year when two missing teenagers were found dead in a Utah mine shaft. Utah’s Division of Oil, Gas and Mining has sealed some 6,000 abandoned mines across the state and aims to close more than 10,000 more. But not everyone wants to them shut. A subculture of explorers has been slipping underground to survey the caverns for years.