ML13015A284

NRC Strawman-Plant Specific IP Content

ML13015A284
Person / Time
Issue date:	01/11/2013
From:	Jessica Kratchman Containment and Balance of Plant Branch
To:	Bauer S, Flaig K Dominion, Nuclear Energy Institute
Jessican Kratchman, NRR/JLD, 415-5112
References
EA-12-049
Download: ML13015A284 (5)

Text

1 Kratchman, Jessica From:

Kratchman, Jessica Sent:

Friday, January 11, 2013 4:26 PM To:

'Kurt Flaig'; 'BAUER, Scott' Cc:

Bowman, Eric; Jackson, Christopher; Mitchell, Matthew; Regner, Lisa; Taylor, Robert; Skeen, David; Reed, Timothy; Burton, Tasheena

Subject:

NRC Strawman-plant specific IP content (EA-12-049)

Attachments:

Information in the plant specific submittal for ELAP.docx Categories:

Important record Scott/ Kurt, I apologize for the delay, but please find attached the NRC Strawman regarding plant-specific content for Integrated Plan submittals (associated with Order EA-12-049, Mitigating Strategies). I think you will find this input valuable.

Per the NRCs requirements, I will be making this email and the attachment publically available.

Thanks.

-Jessie Jessica Kratchman Project Manager Japan Lessons Learned Project Directorate Office of Nuclear Reactor Regulations United States Nuclear Regulatory Commission 301-415-5112

The Information for the Plant Specific Submittal for the Analysis of the Extended Loss of AC Power Event (ELAP)

WCAP-17601 and NEI 12-06 are provided as a guide to NSSS response to an Extended Loss of AC Power Event (ELAP). Part of the resulting submittal requires that the technical basis for certain actions is also provided. The list below may be used to guide licensees in providing a technical basis.

Some licensees may choose to provide their own technical basis and others may rely on WCAP-17601 or a combination of both. Therefore, the list below, is separated into main and subtopics, as well as direction specifically to those licenses who wish to rely on the WCAP. All questions, specifically related to the WCAP will be identified as such. For example,

1. Main Topic

a. Sub-Topic

i. Specific examples.

b. WCAP: Directions for those applying WCAP-17601.

For licensees who use the WCAP, it is suggested they ensure that the WCAP addresses each main and subtopic. Additionally, they need to demonstrate that the analysis performed in the licensee is representative of their plant.

Systems and Strategies

1. Provide a sequence of events (SOE) for the plant-specific ELAP analysis used to support the FLEX mitigation strategies

a. Provide a table of the SOE including time and reference for each event.

b. Provide a description of why the time is reasonably achievable.

i. For example, if you plan to have injection into the RCS by 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, provide a description of why the time is reasonably achievable.

c. Provide a justification or reference demonstrating why performing this action by this time will be acceptable. If this answer is associated with an analysis, provide that analysis.

i. For example, if you plan to have injection into the RCS by 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and you have performed an ELAP analysis which demonstrates that injection by 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> will meet your acceptance criteria, provide that analysis.

d. WCAP: Provide a reference for each event in the SOE table and the applicable sections of the WCAP-17601.

e. WCAP: Identify and justify deviations from the WCAP report.

2. For any analysis used to justify an action, provide a list of the assumptions and values of the plant initial conditions used in that analysis

a. Demonstrate that those assumptions and initial conditions are representative of your plant.

b. WCAP: Confirm that they are the same as or equivalent to that specified in the applicable sections of the WCAP:

i. Section 4.2.1 for all plant types ii. Section 4.2.2 for Westinghouse unique assumptions iii. Section 4.2.3 for Combustion Engineering unique assumptions iv. Section 4.2.4 for Babcock and Wilcox unique assumptions

c. WCAP: Identify the assumptions and values of the plant initial conditions that are different from that in the WCAP and justify their use.

3. Provide discussion of the NSSS acceptance criteria used for the ELAP analysis

a. Identify the acceptance criteria and justify them.

i. The recommended acceptance criteria are those proposed in the WCAP, prevent core damage and no recriticality.

ii. If you plan to use these criteria, identify the specific technical criteria which demonstrate you meet the acceptance criteria.

b. WCAP: Confirm that the criteria are consistent with that discussed in Section 4.3 of the WCAP-17601.

c. WCAP: Identify and justify differences from WCAP-17601.

4. Provide discussion of how containment functions are maintained during ELAP.

a. Identify the acceptance criteria and justify them.

b. WCAP: Does not address containment response.

5. Provide discussion of the reactor coolant pump (RCP) seal leakage rates used for an ELAP.

a. Address the applicability of the model used for the plant specific RCP seal design and analysis at ELAP conditions.

i. Include a discussion of the seal failure time and at which temperature as well as data that supports this time and temperature.

b. If using low-leakage seals, provide validation data which demonstrates the capability of the seals.

c. If using asymmetric cooling of the steam generators, demonstrate that the seal temperature in the non-cooling loop does not exceed the temperature which would cause the seals to fail.

d. WCAP: Address the applicability of the models discussed in the applicable sections of Chapters 4 and 6 in WCAP compared to plant specific RCP Seal Design and operating conditions

i. Section 4.4.1 for Westinghouse ii. Section 4.4.2 and Chapter 6 for Combustion Engineering iii. Section 4.4.3 for Babcock and Wilcox

e. WCAP: For plants with seal leak flow rates expected to be greater than those discussed in the WCAP report, identify and address the differences.

6. Provide operator action and associated action times credited in the ELAP analysis.

a. Where operator action is credited, confirm that such action is consistent with the plant emergency operating or flex mitigation strategies procedures, and that action times are appropriate for the operator to achieve the required action

b. WCAP: same as above.

7. Provide a list of systems and components which are used in the mitigation of an ELAP event.

a. Provide a list of systems and components and their associated mission times.

b. WCAP: Reference the applicable sections of WCAP.

8. Provide the plant parameters that are monitored during the ELAP event.

a. Justify that all (safety or non-safety related) instrumentation and controls used by the operator to measure plant parameters are sufficient to perform their intended functions in the containment conditions expected during ELAP.

b. WCAP: Confirm that they are consistent with that discussed in section 3.4 of WCAP.

c. WCAP: Identify and justify differences of the plant analysis and the WCAP.

9. For the following, confirm whether motive power, valve controls, and valve motive air system will be available, which can be expected to function and provide the desired information within a time frame compatible with the cooldown anticipated in an ELAP event:

a. Steam Generator Pressurized Operator Relief Valve (SG PORV)

b. Auxiliary spray control valve.

c. Auxiliary feedwater valve.

d. WCAP: same as above.

10. Provide discussion of the objectives of the licensees approach to mitigation of the ELAP event.

a. Provide discussion of the objectives and the plans for implementation

b. WCAP: Provide discussion of the licensees position on the recommendations (objectives) in applicable sections of Chapter 3 in WCAP-17601 for the flex mitigation strategies.

i. Section 3.1 for Westinghouse NSSS ii. Section 3.2 for Combustion Engineering NSSS iii. Section 3.3 for Babcock and Wilcox NSSS

c. WCAP: List the recommendations that are applicable to the plant and provide rationale for the applicability and discuss the implementation plan for the recommendations (objectives).

d. WCAP: Provide rationale for each of the recommendations that are determined to be inapplicable to the plant.

Codes and Methods

11. Provide a discussion any computer codes used to perform analysis on the ELAP event.

a. Specifically, demonstrate that the codes have been used before for an event with similar phenomena.

b. If 2-phase cooling (including reflux condensation) is relied upon during the critical portion of the ELAP analysis (such that an error in those models may impact when certain equipment needs to be setup at the plant), justify the capabilities of the computer code to model that phenomena.

12. Provide discussion of the boron mixing model used for the shutdown margin determination in support of the plant FLEX mitigation strategies and address the adequacy of the mixing model for the intended purpose with analysis and/or boron mixing test data applicable to the ELAP conditions.

13. Provide rationale for each of the analyses, that are determined to be applicable to the plant, that are used to support the adequacy of the plant FLEX mitigation strategies

a. Provide discussion for the analysis that addresses the acceptability of the analyses related to methods, assumptions, and the results.

b. WCAP: Provide a list of the applicable sections of Chapter 5 in WCAP documenting the analyses that are used to support the adequacy of the plant FLEX mitigation strategies.

i. Section 5.1 for turbine auxiliary feedwater pump heat and RCS heat loss ii. Section 5.2 for Base scenarios iii. Section 5.3 ELAP coping times, relative to RCS inventory control iv. Section 5.4 for interruption or reduced heat secondary heat sink capacity

v. Section 5.5 RCS depressurization benefit and risk vi. Section 5.6 Passive safety injection for RCS boration and makeup and isolation/venting to prevent gas injection to the RCS vii. Section 5.7 RCS response with little or no RCS leakage viii. Section 5.8 for re-criticality ix. Section 5.9 for instrument line break

c. WCAP: Provide rationale for each of the analyses that are determined to be applicable to the plant.

d. WCAP: Provide discussion for any analyses that are part of the ELAP but have not been included in the WCAP.