From 1968 until permanent shutdown in 1996, Connecticut Yankee operated a 619 megawatt pressurized water reactor at the Haddam Neck site. The nuclear power plant underwent a successful decommissioning from 1998-2007 with all plant structures removed and the site restored to stringent state and federal clean-up standards.
The Connecticut Yankee Atomic Power Company Board of Directors voted to permanently close the CY plant in December 1996. The decision was based on an economic study that concluded that due to changing market conditions, electric customers would save money if the plant were closed.
CY chose immediate dismantlement (the DECON method) because it was the most practical and environmentally responsible option for the plant. Other considerations included the use of current plant employees who were trained and knowledgeable about the facility, prevention of long-term maintenance costs, and the availability of low-level waste disposal facilities. Significant decommissioning activities began at CY in May 1998, and were successfully completed in November 2007 with NRC approval to reduce the land under the NRC license to the approximately 5 acre Independent Spent Fuel Storage Installation.