Kernkraftwerk Rancho Seco

The Rancho Seco Nuclear Generating Station is a decommissioned nuclear power plant built by the Sacramento Municipal Utility District (SMUD) in Herald, California.HistoryIn 1966, SMUD purchased in southeast Sacramento County for a nuclear power plant, which was built in Herald, 25mi south-east of downtown Sacramento.In the early 1970s, a small pond was expanded to a 160acre lake to serve as an emergency backup water supply for the station. The lake has always received its water from the Folsom South Canal and has no relationship with the power plant's daily water supply. Surrounding the lake is of recreational area originally operated by the County of Sacramento for day-use activities.The 2,772 MWt Babcock & Wilcox pressurized water reactor (913 MWe) achieved initial criticality on 16 September 1974 and entered commercial operation on 17 April 1975.On 20 March 1978 a failure of power supply for the plant's non-nuclear instrumentation system led to steam generator dryout. (ref NRC LER 312/78-001). In an ongoing study of "precursors" that could lead to a nuclear disaster if additional failures were to have occurred, in 2005 the United States Nuclear Regulatory Commission concluded that this event at Rancho Seco was the third most serious safety-related occurrence in the United States (Behind the Three Mile Island accident and the cable tray fire at Browns Ferry).