ML24197A230
| ML24197A230 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 07/15/2024 |
| From: | Mark Yoo NRC/NRR/DNRL/NLRP |
| To: | Snider S Duke Energy |
| Shared Package | |
| ML24197A228 | List: |
| References | |
| Download: ML24197A230 (1) | |
Text
RAI - 2024 Annual Update Flow Blockage for Gray Cast Iron and Ductile Iron Fire Hydrants with Internal Coatings/Linings Regulatory Basis:
Section 54.21(a)(3) of Title 10 of the Code of Federal Regulations (10 CFR) requires an applicant to demonstrate that the effects of aging for structures and components will be adequately managed so that the intended function(s) will be maintained consistent with the current licensing basis for the period of extended operation. One of the findings that the U.S.
Nuclear Regulatory Commission (NRC) staff must make to issue a renewed license (10 CFR 54.29(a)) is that actions have been identified and have been or will be taken with respect to managing the effects of aging during the period of extended operation on the functionality of structures and components that have been identified to require review under 10 CFR 54.21, such that there is reasonable assurance that the activities authorized by the renewed license will continue to be conducted in accordance with the current licensing basis. In order to complete its review and enable making a finding under 10 CFR 54.29(a), the staff requires additional information in regard to the matters described in the requests for information.
Background:
Table 3.3-1, ID 063, in NUREG-2192, Standard Review Plan for Review of Subsequent Licene Renewal Applications for Nuclear Power Plants (ML17188A158), addresses managing loss of material and flow blockage [underline added for emphasis] of steel fire hydrants exposed to outdoor air, raw water, raw water (potable), and treated water by the Fire Water System program.
The third annual update to the Oconee Nuclear Station, Units 1, 2, and 3, Subsequent License Renewal Application, dated May 24, 2024 (ML24145A069), added gray cast iron and ductile iron fire hydrants with internal coatings/linings to SLRA Table 3.3.2-24, Auxiliary Systems -
High Pressure Service Water System - Aging Management Evaluation, because an engineering change package approved replacement fire hydrants with an epoxy coating on the inside and outside surfaces.
Issue:
Flow blockage was not identified as an applicable aging effect for the ductile iron fire hydrants with internal coatings/linings exposed internally to raw water in SLRA Table 3.3.2-24.
Regardless if the fire hydrant has an internal coating/lining, it could become blocked due to debris from the raw water source. The staff notes that flow blockage was identified as an applicable aging effect for the ductile iron fire hydrants without an internal coating/lining exposed internally to raw water in SLRA Table 3.3.2-24 (ML21158A194).
Gray cast iron and ductile iron fire hydrants with internal coatings/linings were not added to SLRA Table 3.3.2-26, Auxiliary Systems - Keowee Fire Detection/Protection System - Aging Management Evaluation. Nor were gray cast iron and ductile iron with internal coatings/linings added to SLRA Section 3.3.2.1.26 as materials in the Keowee Fire Detection/Protection System. The staff also notes that flow blockage was identified as an applicable aging effect for
the ductile iron fire hydrants without an internal coating/lining exposed internally to raw water in SLRA Table 3.3.2-26 (ML21158A194).
Request:
- 1. Please discuss why flow blockage was not identified as an applicable aging effect for the ductile iron fire hydrants with internal coatings/linings exposed internally to raw water in SLRA Table 3.3.2-24.
- 2. Please discuss whether SLRA Section 3.3.2.1.26 should include materials gray cast iron and ductile iron with internal coatings/linings and SLRA Table 3.3.2-26 should include gray cast iron and ductile iron fire hydrants with internal coatings/linings, including flow blockage as an applicable aging effect for a raw water internal environment.