The Three Mile Island Nuclear Plant – An Update on the 35th Anniversary

Neil Sheehan
Public Affairs Officer
Region I
 
The Three Mile Island Unit 2 Control Room bustles during the crisis in 1979. For more historical information, click on the photo to go to the NRC YouTube video about the accident.
The Three Mile Island Unit 2 Control Room bustles during the crisis in 1979. For more historical information, click on the photo to go to the NRC YouTube video about the accident.

Today marks 35 years since the accident at the Three Mile Island 2 nuclear power plant. As is the case every year, it represents another opportunity to reflect on the most significant nuclear power plant accident to ever occur in the U.S.

Perhaps less well known to the average citizen is where things stand in terms of the Middletown, Pa., site all these years later.

GPU Nuclear, which owned the plant at the time of the accident, removed the damaged fuel from the reactor and decontaminated the plant in ensuing years. Once the plant was placed in a safe, stable condition, it transitioned to what is known as “post-defueled monitored storage” — a change that was formally approved by the NRC in 1993.

Last year, the current owner, FirstEnergy, submitted a roadmap to the agency on its plans for eventual dismantling the plant. Those details were contained in a document called a Post-Shutdown Decommissioning Activities Report, or PSDAR.

In short, the plant will remain in storage until its neighboring reactor, Three Mile Island 1, permanently ceases operations, something currently expected to happen in 2034. Once that happens, decommissioning work on both units will be undertaken, but those efforts are projected to take many years.

NRC regulations allow up to 60 years for the completion of decommissioning activities for U.S. nuclear power plants.

A view of the TMI-2 control room, last year, with two NRC inspectors.
A view of the TMI-2 control room, last year, with two NRC inspectors.

Meanwhile, the NRC will continue to inspect TMI-2 at regular intervals. The focus of those reviews includes maintenance of the structures, management oversight, fire protection and plant support activities. The results of those inspections can be found in the NRC’s electronic documents system.

While another anniversary has arrived for TMI, the work on keeping close watch on the plant goes on, and will continue for many years to come.