ML12296A216

From kanterella
Jump to navigation Jump to search

Acceptance Review TMI-1 RR-12-02 Letdown Nozzle Weld Swol - TAC ME9818
ML12296A216
Person / Time
Site: Three Mile Island Constellation icon.png
Issue date: 10/22/2012
From: Peter Bamford
Plant Licensing Branch 1
To: Tom Loomis
Exelon Corp, Exelon Generation Co
Bamford P
Shared Package
ml12297A104 List:
References
TAC ME9818
Download: ML12296A216 (1)


Text

From: Bamford, Peter To: "thomas.loomis@exeloncorp.com" Cc: "david.helker@exeloncorp.com"

Subject:

Acceptance Review of Relief Request RR-12-02, Proposed Structural Weld Overlay on Cold Leg Letdown Nozzle Welds (TAC NO. ME9818)

Date: Monday, October 22, 2012 1:55:00 PM By letter dated October 18, 2012 (Agencywide Documents Access and Management System Accession No. ML12292A584), Exelon Generation Company, LLC (Exelon) submitted a relief request for U.S. Nuclear Regulatory Commission (NRC) approval. In the relief request, Exelon proposes to perform a structural weld overlay of the lower cold leg letdown nozzle dissimilar metal welds (DMWs) and Alloy 600 safe-end at Three Mile Island, Unit 1 (TMI-1). The proposed overlay is intended to proactively mitigate the potential for Primary Water Stress Corrosion Cracking degradation, which DMWs have shown a propensity for, in Pressurized Water Reactor (PWR) reactor coolant systems.

TMI-1 plans to install the overlay during a refueling outage scheduled to begin in the fall of 2013.

The purpose of this email is to provide the results of the NRC staff's acceptance review of the subject relief request. The acceptance review was performed to determine if there is sufficient technical information in scope and depth to allow the NRC staff to complete its detailed technical review. The acceptance review is also intended to identify whether the application has any readily apparent information insufficiencies in its characterization of the regulatory requirements or the licensing basis of the plant.

The NRC staff has reviewed your submittal and concluded that the request does provide technical information in sufficient detail to enable the NRC staff to continue with its detailed technical review and make an independent assessment regarding the acceptability of the proposed request in terms of regulatory requirements and the protection of public health and safety and the environment. Given the lesser scope and depth of the acceptance review as compared to the detailed technical review, there may be instances in which issues that impact the NRC staffs ability to complete the detailed technical review are identified despite completion of an adequate acceptance review. If additional information is needed, you will be advised by separate correspondence.

Peter Bamford NRR/DORL/LPL 1-2 Beaver Valley & TMI-1 Project Manager 301-415-2833