(Susan Montoya Bryan | AP file photo) This April, 2006, file photo shows the Four Corners Power Plant in Waterflow, N.M., near the San Juan River in northwestern New Mexico. The closure of the coal-fired power plant on the Navajo Nation sooner than expected will be a major blow to a region where coal has been a mainstay of the economy for decades. Arizona Public Service Co. now plans to shutter the Four Corners Power Plant in 2031 when its coal contract expires rather than wait until 2038.