Xcel Energy, the utility company that runs the plant, said the spillage was "fully contained on-site and has not been detected beyond the facility". "Xcel Energy took swift action to contain the leak to the plant site, which poses no health and safety risk to the local community or the environment," the Minnesota-based utility said in a statement on Thursday. Roughly one-quarter of the spilled tritium has been recovered so far, and Xcel has said it may build above-ground storage tanks to store the contaminated water