ML25086A006
| ML25086A006 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 03/26/2025 |
| From: | Mark Yoo NRC/NRR/DNRL/NLRP |
| To: | Wilson C Constellation Energy Generation |
| References | |
| Download: ML25086A006 (1) | |
Text
REQUEST FOR CONFIRMATION OF INFORMATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION DRESDEN, UNITS 2 AND 3, SUBSEQUENT LICENSE RENEWAL REVIEW - SAFETY CONSTELLATION ENERGY GENERATION, LLC DRESDEN, UNITS 2, 3 DOCKET NO. 05000237, 05000249 ISSUE DATE: 3/26/2025 Set #2 RCI 3.3.2-1 Subsequent License Renewal Application (SLRA) Table 3.3.2-8 credits the Fire Water System program for managing flow blockage, hardening or loss of strength, and loss of material for the polymer piping and piping components exposed internally to raw water. The items in the SLRA cite Aging Management Review (AMR) item 3.3.1-263 with generic note E.
AMR item 3.3.1-263 in NUREG-2192, Standard Review Plan for Review of Subsequent License Renewal Applications for Nuclear Power Plants (ML17188A158), manages hardening or loss of strength due to polymeric degradation; loss of material due to peeling, delamination, wear; cracking or blistering due to exposure to ultraviolet light, ozone, radiation, or chemical attack; and flow blockage due to fouling for polymeric piping and piping components exposed to raw water.
In the letter dated February 20, 2025 (ML25051A253), the applicant revised plant-specific note 5 to SLRA Table 3.3.2-8 related to the buried polymer piping and piping components in the Fire Protection System. Specifically, the note identified the polymeric piping in the Fire Protection System as polyurethane based cured-in-place-polymer-pipe liner.
During the audit of the Fire Water System program, the applicant stated that cracking or blistering are not applicable aging effects because the raw water from the Kankakee River does not contain aggressive chemicals, and no degradation of the polymeric piping was identified from an operating experience search.
Please confirm that the raw water environment for the polyurethane based cured-in-place-polymer-pipe liner in the Fire Protection System does not contain aggressive chemicals that may cause cracking or blistering. In addition, please confirm that there is no plant-specific operating experience for the polyurethane based cured-in-place-polymer-pipe liner exposed internally to raw water in the Fire Protection System due to age-related degradation.
RCI B.2.1.27-1 Based on discussions between the applicant and staff during the audit, it is the staffs understanding that carbon fiber reinforced polymer (CFRP) piping and piping components in the condensate system (SLRA Table 3.4.2-1) is referring to a CFRP wrap applied over existing piping, such that the internal surface of the wrap is not in direct contact with the treated water environment but is in direct contact with the soil environment. Confirm that this is an accurate assessment.
RCI B.2.1.11
Background:
As shown below in B.2.1.11, the OCCW System manages carbon fiber reinforced polymer for loss of material, cracking, hardening or loss of strength, reduction of heat transfer, and flow blockage.
B.2.1.11 Open-Cycle Cooling Water System Program Description
[Description clipped for brevity] The program applies to components constructed of steel, cast iron, stainless steel, copper alloys, and carbon fiber reinforced polymer.
The program manages piping, piping components, and heat exchanger components in safety-related and nonsafety-related raw water systems that are exposed to a raw water environment for loss of material, cracking, hardening or loss of strength, reduction of heat transfer, and flow blockage.
In Table 3.3.1, the OCCW System AMP is called out to manage hardening or loss of strength, and loss of material for CFRP but flow blockage and cracking are not mentioned, despite being listed as aging effects requiring management (AERMs).
In Table 3.3.2-12, hardening or loss of strength, and loss of material for CFRP are listed but flow blockage and cracking are not.
Confirm that:
- 1. Based on discussions between the applicant and staff during the audit, it is the staffs understanding that CFRP piping and piping components in the open cycle cooling water system are referring to a CFRP wrap applied over existing piping, such that the internal surface of the wrap is not in direct contact with the raw water environment and therefore, flow in these lines does not affect the intended function of spatial interaction. Confirm that this is an accurate assessment.
- 2. Based on discussions between the applicant and the staff during the audit, it is the staffs understanding that CFRP piping in the open cycle cooling water system underwent chemical resistance testing (i.e., pickle jar test) to ensure the CFRP was appropriate for use due to exposure to ultraviolet light, ozone, radiation, or chemical attack and therefore, cracking or blistering are not applicable aging mechanisms. Confirm that this is an accurate statement.