ML15036A431
| ML15036A431 | |
| Person / Time | |
|---|---|
| Site: | Braidwood  |
| Issue date: | 02/05/2015 |
| From: | Joel Wiebe Plant Licensing Branch III |
| To: | Krejcie J Exelon Corp |
| References | |
| Download: ML15036A431 (3) | |
Text
1 NRR-PMDAPEm Resource From:
Wiebe, Joel Sent:
Thursday, February 05, 2015 12:59 PM To:
Jessica Krejcie
Subject:
Preliminary RAIs for LAR Regarding Braidwood Station Technical Specification, "Ultimate Heat Sink"
- Jessica, By letter dated August 19, 2014 (ADAMS Accession No. ML14231A902), as supplemented by letter dated January 20, 2015 (ADAMS Accession No. ML15020A246), Exelon submitted a license amendment request to raise the Braidwood Station, Unit 1 and Unit 2, technical specification 3.7.9.2 limit of 100° F to 102° F. During the acceptance review the NRC staff determined that the submittal contained sufficient information to initiate a contract to obtain resources to support the NRC staff review of the submittal. As a result, the NRC staff will not continue the acceptance review process.
During our initial look at the submittal, the NRC staff identified information that is needed to support our review. These initial questions are provided to promote early communication of needed information. Because these questions were developed during our brief look at the submittal to support our contract process, additional questions may arise during our detailed review of the submittal.
A response to the following requests for additional information is requested within 30 days. If clarification of the questions is needed, contact me at 301-415-6606 or Joel.Wiebe@nrc.gov.
- 1. On page 17 of Attachment 1 to the August 19, 2014, letter, various safety analyses were identified that were not affected by the proposed UHS temperature increase. Provide the rationale used to support the determination that the increased UHS temperature will not affect the results of the following safety analyses.
LOCA Analyses including Large and Small Breaks Analyses, Long-Term-Cooling/Post-LOCA Boric Acid Precipitation, and LOCA Forces UFSAR Chapter 15 Transient Analyses for Various Non-LOCA Events Low Temperature Overpressure Protection (LTOP) Analysis Evaluation of the Reactor Coolant Pump and Reactor Coolant Pump Motor Limits on Component Cooling and Seal Injection Temperatures Control Systems Operability/Margin to Trip/Component Sizing Evaluations Which Reviewed the Control and Protection System Setpoints to Verify that the System Capacities do not change The information to be provided should include for each of the applicable analyses (1) a listing of equipment that are directly or indirectly supported by the UHS, and were credited in the above safety analyses, (2) the assessment of the effects of increased UHS temperature on equipment identified in above item (1), and (3) the impacts of the increased UHS temperature on the affected safety analyses. For the non-LOCA transient analyses, the requested information should be provided for each of the applicable events discussed in UFSAR Chapter 15.
- 2. Provide the dimensions and volume of the essential cooling pond.
- 3. Describe the flow path of cooling water from the discharge of the essential service water discharge pipe inside the essential cooling pond to the lake screen house in terms of effective volume and surface area. Quantify the effective volume and surface area. Use sketches as necessary to indicate effective volume, effective surface area and flow.
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- 4. Describes the LakeT-PC model including size, surface area and volume of each plug and the number of plugs.
- 5. Provide justification that demonstrates that the LakeT-PC model accurately represents the effective essential cooling pond volume and surface area with sufficient accuracy and within the margin of error for the temperature of cooling water that supplies the safety related loads.
- 6. Describe how the precision temperature instrument is used to monitor the SX pump discharge temperature to ensure the new SR limit is not exceeded. Specifically, Section 3.7 describes operator actions when the UHS temperature starts increasing during current operation. However, this description does not explain how the precision temperature instrument (described in Section 3.8) would be used to verify the temperature when the temperature of any operating SX pump discharge temperature exceeds 97°F.
- 7. Provide justification that demonstrates that the increase in the maximum cooling water temperature to 105.2 F does not adversely affect the uncertainty of the UHS precision temperature instrument. The August 19, 2014, letter states the UHS precision temperature instrument has a maximum uncertainty of 0.07°F. However, details on the specifications for the instrumentation being used has not been provided to allow verification of the identified uncertainty. Furthermore, the letter does not describe the impact that an increase in the maximum cooling water temperature of 105.2 F may have on the uncertainty of the UHS precision temperature instrument.
Hearing Identifier:
NRR_PMDA Email Number:
1858 Mail Envelope Properties (Joel.Wiebe@nrc.gov20150205125900)
Subject:
Preliminary RAIs for LAR Regarding Braidwood Station Technical Specification, "Ultimate Heat Sink" Sent Date:
2/5/2015 12:59:26 PM Received Date:
2/5/2015 12:59:00 PM From:
Wiebe, Joel Created By:
Joel.Wiebe@nrc.gov Recipients:
"Jessica Krejcie" <Jessica.Krejcie@exeloncorp.com>
Tracking Status: None Post Office:
Files Size Date & Time MESSAGE 4785 2/5/2015 12:59:00 PM Options Priority:
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No Reply Requested:
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