Decommissioning is the process by which nuclear power plants are safely retired from service.

After the closure of a nuclear power plant, the plant owner is accountable for reducing the site’s residual radioactivity to safe levels. The site must be decommissioned within 60 years of the plant closure. The decommissioning process involves removing the used nuclear fuel from the reactor, placing it into the used fuel pool and eventually into dry storage containers (which can be stored on-site or transported off-site), dismantling systems or components containing radioactive products (e.g., the reactor vessel) and cleaning up or dismantling contaminated materials from the facility.

Once the decommissioning process is complete, the NRC terminates the owner’s license and releases the site property for other uses.

• Constellation purchased TMI Unit 1 in 2000, producing approximately 800 megawatts of carbon-free electricity, enough to power about 800,000 homes annually for almost two decades with virtually no greenhouse gas emissions. 
• Over the years, the station and its employees pumped more than $3.5 billion into the local economy, including wages, taxes, and local purchases. 
• Since 2000, TMI Unit 1 contributed $6 million to local charitable organizations and non-profits, with employees spending almost 40,000 hours volunteering in the community.  
• Safety and performance excellence were a top priority, with more than 5.9 million hours and counting worked safely once Constellation purchased the unit.
• Since 2000, TMI Unit 1 offset more than 95 million metric tons of carbon, the equivalent of nearly 20 million cars off the road. 
• The station is such a landmark in the Londonderry Township community that artwork of the island is painted on the sides of several fire engines and the Lower Dauphin Communities That Care “Bookmobile.”

To decommission a nuclear power plant, the licensee must submit a post‐shutdown decommissioning activities report to the Nuclear Regulatory Commission (NRC). This report provides a description of the planned decommissioning activities, a schedule for accomplishing them, and an estimate of the expected costs.

The site must be decommissioned within 60 years of the plant ceasing operations.

The decommissioning process involves removing the used nuclear fuel from the reactor, dismantling systems or components containing radioactive products (e.g., the reactor vessel), and cleaning up or dismantling contaminated materials from the facility. Contaminated materials can be disposed of in two ways: decontaminated on site or removed and shipped to a waste processing, storage or disposal facility.

During TMI Unit 1 decommissioning, a team of employees will remain on-site.

• Security: Guards will safeguard the facility until all nuclear fuel has been removed from the site. 
• Engineers, technicians, and specialty workers: A highly-qualified, skilled staff of experts will oversee and conduct the entire dismantlement process. 
• Environmental scientists: Using company employees and contracted experts, Constellation will continue a strong environmental monitoring program through decommissioning. 
• Emergency responders: Teams of qualified employees, both on and off-site, will be on-call all day, every day to work to protect the plant and the public in an unlikely emergency situation.