The Monticello Nuclear Generating Plant is one of the five oldest plants in the United States and hosts a single GE BWR-3 reactor in Monticello, Minnesota, on the banks of the Mississippi River. Xcel Energy, the utility which owns and operates the nuclear power plant is conducting power uprate studies which would increase the plants generating capacity from 613 megawatts to 700 megawatts. Currently, the plant is in the middle of its 26th scheduled refueling outage and power capacity expansion work is being conducted onsite.
On May 31st staff at Monticello were conducting a focused self-assessment of the external flooding mitigation standards in place at the nuclear plant, when it was determined that the current standards may not adequately protect critical equipment which are required to maintain safe shutdown from external probable maximum floods. The staff will have to set new compensatory measures in place ranging including procedural changes, additional barriers, and contingency actions.
Source: NRC Event Notifications