ML23354A211

Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5

ML23354A211
Person / Time
Site:	Three Mile Island
Issue date:	12/20/2023
From:	Jeffery Lynch TMI-2 Solutions
To:	Office of Nuclear Material Safety and Safeguards, Document Control Desk
References
TMI2-RA-COR-2023-0022
Download: ML23354A211 (1)

Text

December 20, 2023 TMI2-RA-COR-2023-0022 10 CFR 50.82 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Three Mile Island, Unit 2 NRC Possession Only License No. DPR-73 NRC Docket No. 50-320

Subject:

Response to Request for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5

References:

(1) Letter TMI2-RA-COR-2021-0004 from van Noordennen, G. P. (EnergySolutions) to Document Control Desk (U.S. NRC), Notification of Amended Post-Shutdown Decommissioning Activities Report (PSDAR) for Three Mile Island, Unit 2 in Accordance with 10 CFR 50.82(a)(7), Revision 4, dated March 17, 2021 (ML21084A229)

(2) Letter TMI2-RA-COR-2022-0022 from Lackey, M. B. (EnergySolutions) to Document Control Desk (U.S. NRC), Notification of Amended Post-Shutdown Decommissioning Activities Report (PSDAR) for Three Mile Island, Unit 2 in Accordance with 10 CFR 50.82(a)(7), Revision 5, dated October 27, 2022 (ML22306A051)

(3) U.S. NRC, TMI Unit 2, PSDAR Rev. 5 RAIs, dated June 29, 2023 (E-Mail:

ML23187A020; RAIs: ML23187A033)

(4) Letter TMI2-RA-COR-2023-0014 from Devik, T. (EnergySolutions) to Document Control Desk (U.S. NRC), Response to Requests for Additional Information for the TMI-2 Post-Shutdown Decommissioning Activities Report, Rev. 5, dated August 8, 2023 (ML23221A140)

TMI-2Solutions submitted the TMI-2 Post-Shutdown Decommissioning Activities Report (PSDAR) Rev. 4 on March 17, 2021 (Reference 1) and Rev. 5 on October 27, 2022 (Reference 2).

By E-mail dated June 29, 2023 (Reference 3), the NRC issued Requests for Additional Information (RAIs) to support its review of the PSDAR. TMI-2Solutions responded to the RAIs on August 8, 2023 (Reference 4) by providing an updated Decommissi oning Cost Estimate (RAI 2) and stated its plans to provide the NRC a supplement to the PSDAR by December 28, 2023 (RAIs 1 and 3). of this letter provides updated responses to RAIs 1 and 3.

TMI2-RA-COR-2023-0022 Page 2 of 2 If the NRC has any questions with respect to the c ontent of this document or wishes to obtain any additional information, please contact Timothy Devik, TMI-2 Licensing Manager, at (603) 384-0239 or trdevik@energysolutions.com.

Sincerely,

Joseph R. Lynch Director, D&D Regulatory Affairs/Licensing EnergySolutions

Attachment:

- Responses to RAIs 1 and 3

cc: w/Attachment

NRC Regional Administrator - Region I NRC Lead Inspector - Three Mile Island Nuclear Station - Unit 2 NRC Project Manager - Three Mile Island Nuclear Station - Unit 2 Director, Bureau of Radiation Protection - PA Dept of Environmental Protection Chief, Division of Nuclear Safety, Bureau of Radiation Protection - PA Dept of Environmental Protection Chairman, Board of County Commissioners - Dauphin County Manager - Londonderry Township Attachment 1 TMI2-RA-COR-2023-0022

to TMI2-RA-COR-2023-0022 Responses to RAIs 1 and 3

3 Pages Follow Attachment 1 TMI2-RA-COR-2023-0022

RAI-1

Is the description of planned decommissioning activities and the associated schedule accurate given that TMI-2S plans to delay building demolition until 2045. Please provide your plans to update the PSDAR to reflect any change [to] decommissioning method, decommissioning activities, and the schedule. This should also include when TMI-2S plans to move from DECON to SAFSTOR, as the Decommissioning Fund Status Report states there will be a gap between 2029 and 2045 before building demolition.

TMI-2Solutions Response:

As stated in TMI-2Solutions previous response to RAI 1 (ML23221A140, Reference 4), TMI-2Solutions does not intend to change the decommissioning method to SAFSTOR following the completion of Phase 1b. However, additional time is needed to fully evaluate the impact of the unique challenges presented by the radiological conditions at TMI-2 on project plans, contingencies, and timing.

As described in PSDAR Section 3.1.2, the purpose of Phase 1b is to perform the activities associated with Fuel Bearing Material (FBM)1 recovery and source term reduction necessary to reduce radiological conditions at TMI-2 to levels that are generally consistent with a plant at the end of its operating life. Phase 1b includes packagi ng, transport, and storage of the remaining FBM on the Three Mile Island Independent Spent Fuel Storage Installation (ISFSI).

Unlike other reactor facilities undergoing decommissioning, the source of remaining radiation at TMI-2 is distributed throughout the Reactor Building and portions of the Auxiliary and Fuel Handling buildings. Thus, each area requires its own decontamination strategy and additional planning. For example, TMI-2Solutions has been performing mockups of plans to mitigate the radiological risks from legacy contaminated debris in the Reactor Building basement, as well as procuring and training on robotic tools to perform demolition of the concrete-block stairwell/elevator structure and scabbling of the walls. TMI-2Solutions also has and continues to assess innovative technologies and chemical decontamination methods through coordination with numerous specialty vendors to determine the most effective strategies to perform Phase 1b activities.

Table 5-1 of the PSDAR shows Rad Building source term reduction, which includes the Reactor Building basement activities, occurring in parallel with Large Component and Reactor Vessel source term reduction. Additional and recent char acterization following TMI-2 entry into DECON using robotics and LiDar scanning provided TMI-2Solutions with new information about radiological conditions in areas of the Reactor Building that were previously inaccessible during the Post-Defueling Monitored Storage (PDMS) condition. Based on the dose rates measured and ALARA principles, TMI-2Solutions has been reassessing the sequence of several major decommissioning activities in the Reactor Building.

1 FBM refers to any component or pieces of components associated with pressurized water operations that have been contaminated by used nuclear fuel and/or the associated isotopes in used nuclear fuel. This term is synonymous with legacy terms used to describe the remaining ~1% of UO2 fuel inventory remaining at TMI-2 (e.g., Debris Material, Core Debris, Fuel Bearing Waste). GPU Nuclear submitted the final Defueling Completion Report to the NRC on February 22, 1990, which provided the results of the extensive defueling efforts completed prior to TMI-2 entering Post-Defueling Monitored Storage in 1993. The total fuel removal from the initial TMI-2 cleanup was approximately 99% of the original core loading, and the possibility of criticality in the TMI-2 Reactor Building is precluded.

1 of 3 Attachment 1 TMI2-RA-COR-2023-0022 Because of the unique challenges presented by the radiological conditions at TMI-2 as described above, a 90-day extension is needed to finalize updated schedule information for the PSDAR.

TMI-2Solutions plans to provide this supplemental information to the NRC by March 20, 2024. In addition to the PSDAR, TMI-2Solutions provides routine updates to the TMI-2 Community Advisory Panel (CAP) regarding ongoing decommissioning plans and activities to foster information exchange with members of the public. The TMI-2 CAP is a volunteer organization that was established to engage the local community and facilitate communications regarding the TMI-2 decommissioning project. Past meeting minut es and presentations are publicly available on the TMI-2Solutions website at www.tmi2solutions.com.

RAI-3

PSDAR Section 6.1.14 Cultural, Historic, and Archeological Resources does not reflect the latest information submitted in the January 20, 2023 RAI responses (ML23121A249) and the February 22, 2023 LAR (ML23058A064), that was submitted for review [of] major decommissioning activities, as defined in 10 CFR 50.2, that would diminish the historic integrity (e.g., physical demolition) of the TMI-2 Solutions owned buildings previously deemed eligible for the National Register of Historic Places. Please confirm that this information remains accurate and your plans to update the PSDAR due to the change in major decommissioning activities.

TMI-2Solutions Response Based on the information submitted in the January 20, 2023, RAI responses (ML23121A249) and February 22, 2023, LAR (ML23058A064), TMI-2Solutions proposes Section 6.1.14 of the PSDAR be revised in its entirety with the following:

In Section 4.3.14.2 of the Final Generic Environmental Impact Statement on Decommissioning of Nuclear Facilities, NUREG-0586, Supplement 1 (Decommissioning GEIS), the NRC states that impacts to cultural, historical, or archaeological re sources are considered detectable if an activity has a potential to have a discernable adverse effect on the resources. The impacts are destabilizing if the activity would degrade the resource to the poi nt that it would be of significantly reduced value to the future generations, such as physically damaging structures or artifacts or destroying the physical context of the resource in its environment. The NRC also states that the nuclear facility itself could be potentially eligible for inclusion in the National Register of Historic Places (NRHP).

In this case, appropriate mitigation would be deve loped in consultation with the State Historic Preservation Office (SHPO). Under the National Historic Preservation Act (NHPA), mitigation is determined through the Section 106 process, which seeks to accommodate historic preservation concerns with the needs of Federal undertakings through consultation among the agency official and other parties with an interest in the effects of the undertaking on historic properties.

A Historic Resource Survey Form (HRSF) was completed by the Pennsylvania Historic and Museum Commission (PHMC) in 2010 which stated that the TMI-2 Historic District above-ground resource (Key No. 156047) is eligible for the NRHP under Criterion A (properties significant for their association with event that have made a significant contribution to the broad patterns of history), and under Criterion Consideration G (properties that have achieved significance within the last 50 years), with a period of significance from March 28, 1979 - April 4, 1979 (ML21084A229). A map of the TMI-2 Historic District above-ground resource as well as a boundary survey map depicting TMI-2Solutions-owned parcels were provided to the NRC in a

2 of 3 Attachment 1 TMI2-RA-COR-2023-0022 letter dated January 20, 2023 (ML23025A039). In a letter dated July 28, 2023 (ML23209A763),

the PA SHPO confirmed that the TMI-2 Historic District resource remains individually eligible for listing in the NRHP.

The removal, dismantlement, and disposal of contaminated systems, structures, and components, as well as the eventual and necessary physical demolition of the facility, is imperative to protection of public health and safety and maintaining environmental welfare, and there is no viable alternative to decommissioning that achieves this goal. However, given the exceptional historical significance of the TMI-2 facility, the eventual and necessary physical demolition of the TMI-2Solutions-owned buildings previously deemed eligible for the NRHP is an adverse effect that requires mitigation to be developed in consultation with the PA SHPO and other consulting parties per 36 CFR 800. In accordance with the guidance set forth in the Decommissioning GEIS, TMI-2Solutions submitted a License Amendment Request (LAR) for NRC review of major decommissioning activities, as defined in 10 CFR 50.2, that would diminish the historic integrity (e.g., physical demolition) of the TMI-2Solutions-owned buildings previously deemed eligible for the NRHP (ML23058A064; RAI Supplement, ML23121A249). In a letter dated March 31, 2023 (ML23062A737), the NRC stated that, in order for the NRC to conduct its review and to allow appropriate mitigation to be developed, the NRC plans to initiate consultation for this undertaking under Section 106 of the NHPA. The Section 106 review will consider potential effects to above-and below-ground cultural resources within the Area of Potential Effect.

Based on the above, TMI-2Solutions concludes that the potential environmental impacts regarding historical, cultural, and archaeological resources will be reviewed through the site-specific environmental review for the LAR.

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