ALBUQUERQUE, N.M. (AP) — U.S. land managers violated environmental laws and their own regulations when issuing dozens of leases to drill in one of the nation's busiest oilfields, environmentalists claimed Monday in the latest lawsuit aimed at getting the federal government to consider the cumulative effects of oil and gas development. WildEarth Guardians filed its complaint Monday in U.S. District Court, claiming the oil boom in southeastern New Mexico is a threat to Carlsbad Caverns National Park and the surrounding area's cave systems and desert slopes. The group also is concerned about d...