Three Mile Island - Unit 2

1.0 Site Identification

Type of Site: Power Reactor Facility
Location: Middletown, PA
License No.: DPR-73
Docket No.: 50-320
License Status: DECON
Project Manager: Amy Snyder

2.0 Site Status Summary

The Three Mile Island, Unit 2 (TMI-2) operating license was issued on February 8, 1978, and commercial operation was declared on December 30, 1978. On March 28, 1979, the unit experienced an accident which resulted in severe damage to the reactor core. (For details, see the Backgrounder on the Three Mile Island Accident.)

TMI-2 has been in a non-operating status since that time. The licensee conducted a substantial program to defuel the reactor vessel and decontaminate the facility. All spent fuel, including debris material that contains spent fuel, has been removed, except for some debris material in the reactor coolant system and ex-vessel (a total quantity of residual fuel is estimated to be less than 1125 kg or approximately 1 percent of the original core inventory). Ex-vessel, means the areas outside the reactor vessel (RV) that resulted from fuel material transport within the RV and from the RV to locations outside the RV as described in the GPU Nuclear, TMI 2 Defueling Completion Report (ML111100641).This debris material is primarily in the form of finely divided, small particle-size sediment material, resolidified material either tightly adherent to components or in areas inaccessible to defueling, and adherent films on surfaces contained within piping, tanks, and other components.

The removed fuel (TMI-2 debris) is currently in storage Idaho Nuclear Technology and Engineering Center (INTEC) on the Idaho National Laboratory (INL) Site, formerly known as the Idaho National Environmental and Engineering Laboratory, in Butte County, Idaho, in 10 CFR Part 72- specific Independent Spent Fuel Storage Installation (ISFSI) and the U.S. Department of Energy has taken title and possession of the fuel. TMI-2 has been defueled and decontaminated to the extent the plant is in a safe, inherently stable condition suitable for long-term management, similar to SAFSTOR where the facility would remain until decommissioning at some later time. This long-term management condition was termed post-defueling monitored storage (PDMS), which was approved in 1993. At that time, the license was changed to a Possession Only License (POL).

On December 18, 2020, the TMI-2 POL license was transferred to TMI-2 Solutions, a wholly owned subsidiary of Energy Solutions. Following the license transfer (ML20352A381) and closing (ML20350B569), TMl-2 entered what the licensee called “Phase 1” of its decommissioning plan while the facility remained in a PDMS condition. The stated purpose of the license transfer was to enable the accelerated decommissioning of TMI-2 (i.e., with completion by 2037 instead of 2053). However, with the submission of its most recent annual decommissioning trust fund report, dated March 30, 2023, the licensee now plans to terminate the license by 2052 due to market conditions (ML23094A116).

On October 27, 2022, TMI-2 Solutions submitted the TMI-2 Amended Post-Shutdown Decommissioning Activities Report (ML22306A051). The Nuclear Regulatory Commission (NRC) staff is currently reviewing it for acceptability.

March 31, 2023, the NRC issued License Amendment No. 67 (ML23051A042) to the TMI-2 POL in response to TMI-2 Solutions, License Amendment Request dated February 19, 2021 (ML21057A046). This amendment eliminates certain technical specification requirements based on the current radiological conditions; relocates certain administrative controls to the Decommissioning Quality Assurance Plan; and removes multiple license conditions that are no longer applicable. Under this amendment, the licensee can conduct source reduction and some building demolition; however, buildings that are eligible for the National Registry of Historic Property will not be authorized for demolition until all environmental impacts have been evaluated.

In its license amendment request (LAR) submitted February 22, 2023 (ML23058A064), TMI-2 Solutions requests review of major decommissioning activities, as defined in 10 CFR 50.2, “Definitions,” that would diminish the historic integrity (e.g., physical demolition) of the TMI-2 Solutions owned buildings at TMI-2 previously deemed eligible for the National Register of Historic Places (NRHP) by the Pennsylvania State Historic Preservation Office (SHPO). TMI-2 Solutions explains that demolition of the properties deemed eligible for the NRHP could result in an environmental impact not bounded by the Decommissioning Generic Environmental Impact Statement (NUREG-0586, Supplement 1, Vol. 1) (ML023470304) with respect to cultural, historic, and archaeological resources if appropriate mitigation is not developed in consultation with the SHPO. The requested action is limited to evaluating the previously unbounded environmental impacts on cultural, historical, and archaeological resources given the historic nature of the NRHP eligible properties, and more specifically, to initiate consultation under the National Historic Preservation Act. The NRC accepted this LAR for review on March 31, 2023 (ML23082A342).

TMI-2 Solutions plans to decommission TMI-2 independently of Three Mile Island Station, Unit 1. Specifically, TMI-2 Solutions plans to conduct Source Term Reduction starting mid-2023 to mid-2028; go into SAFSTOR 2029 to 2045 (e.g., security, monitoring, and project oversight); conduct active demolition from 2046 to 2052; conduct Fuel Debris Storage Management starting mid-2029 through 2053; and terminate the license by the end of 2052 (ML23094A116).

3.0 Major Technical or Regulatory Issues


4.0 Estimated Date For Closure

Calendar year 2052, except for an area set aside for storage of the fuel bearing material (TMI-2 Debris Material) on a generally licensed TMI-2 ISFSI that is currently in the planning stage.

Page Last Reviewed/Updated Monday, May 01, 2023