ALBUQUERQUE, N.M. (AP) — Officials at the nation's only underground nuclear waste repository will be flipping the switch on an interim ventilation system this week, allowing mining to resume for the first time since a 2014 radiation release contaminated part of the facility. Still, they caution it will be a few years before the flow of air is enough to meet the pace of operations before the leak. Bruce Covert, president of the contractor that runs the Waste Isolation Pilot Plant, said testing was done and the U.S.