A decades-old urban legend was put to rest Saturday when workers for a documentary film production company recovered “E.T.” Atari game cartridges from a heap of garbage buried deep in the New Mexico desert. The “Atari grave” was, until that moment, a highly debated tale among gaming enthusiasts and other self-described geeks for 30 years. The story claimed that the video game company sent about a dozen truckloads of cartridges to be forever hidden in a concrete-covered landfill in southeastern New Mexico.