ML043000048

Request for Additional Information, Proposed Draft Implementation Guidance for Risk Management Technical Specifications (Rmts) Initiative 7 TSTF-427, Hazard Barriers, & Rmts Initiative 6 Proposed CEOG TSTF-426

ML043000048
Person / Time
Issue date:	11/13/2004
From:	Tjader T NRC/NRR/DIPM/IROB
To:	Bradley B Nuclear Energy Institute
Tjader T., NRC/IROB, 415-1187
References
Download: ML043000048 (13)

Text

November 13, 2004 Mr. Biff Bradley Nuclear Energy Institute Suite 400 1776 I Street, NW Washington, DC 20006-3708

Dear Mr. Bradley:

The Nuclear Regulatory Commission (NRC) staff has completed its review of the Nuclear Energy Institute (NEI) proposed Draft Implementation Guidance for Risk Management Technical Specifications (RMTS) Initiative 7 TSTF-427, Hazard Barriers, and the RMTS Initiative 6 proposed CEOG TSTF-426, Revised Actions to Preclude Entry into LCO 3.0.3.

Enclosed are the staff comments and requests for additional information (RAIs) on the Implementation Guidance for RMTS Initiative 7 TSTF-427 (enclosure 1), and on the Initiative 6 proposed CEOG TSTF-426 (enclosure 2).

We are prepared to meet with you to further discuss these comments and RAIs to ensure that the Implementation Guidance for RMTS Initiative 7 TSTF-427, and the Initiative 6 proposed CEOG TSTF-426 are acceptable, and to ensure continued progress.

Please contact me at (301) 415-1187 or e-mail trt@nrc.gov if you have any questions or need further information on these proposed changes.

Sincerely,

/RA/

T. R. Tjader, Senior Reactor Engineer Technical Specifications Section Reactor Operations Branch Division of Inspection Program Management Office of Nuclear Reactor Regulation

Enclosures:

As stated cc: See attached page

ML043000048 DOCUMENT NAME: G:\DIPM\TSS\Tjader\RAI-RMTS-I6TSTF426-I7HBIG-Ltr-10-04.wpd OFFICE SRE:TSS:IROB:DIPM SC:TSS:IROB:DIPM NAME TRTjader THBoyce DATE 10/26/2004 11/13/2004 Mr. Biff Bradley cc via e-mail:

Mr. Tony Pietrangelo Mr. Rick Hill Nuclear Energy Institute General Electric Nuclear Energy Mr. Biff Bradley Mr. Michael S. Kitlan, Jr.

Nuclear Energy Institute Duke Energy Corporation Mr. Mike Schoppman Mr. Noel Clarkson Nuclear Energy Institute Duke Energy Corporation Mr. Alan Hackerott, Chairman Mr. Donald Hoffman Omaha Public Power District EXCEL Services Corporation Mr. Jim Kenny Mr. Ted Book Pennsylvania Power & Light Company Framatech-ANP Mr. James Andrachek Mr. R. J. Schomaker Westinghouse Electric Company Framatech-ANP Mr. Jack Stringfellow Mr. J. E. Rhoads Southern Nuclear Operating Company Energy Northwest Mr. Donald McCamy Mr. Ken Canavan Browns Ferry Nuclear Plant DS&S Mr. Ray Schneider Mr. Sam Chien Westinghouse Electric Company SCE Mr. Frank Rahn Mr. Gary Chung EPRI SCE-SONGS Mr. Wayne Harrison Mr. Courtney Smyth STP PSEG Nuclear LLC Mr. Drew Richards Mr. Jerry Andre STP Westinghouse Electric Company Mr. Gabe Salamon Mr. David Helher PSEG Nuclear Exelon Mr. Gene Kelly Exelon

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COMMENTS AND REQUEST FOR ADDITIONAL INFORMATION (RAI)

ON TSTF-427 (NEI 04-08 [DRAFT Rev 13])

INDUSTRY IMPLEMENTATION GUIDANCE FOR INITIATIVE 7a (BARRIERS)

General

1. The applicability of the proposed LCO 3.0.9 should be allowed only when at least one train of a multi-train system, other than the one impacted by the barrier degradation, is operable. This should be clarified in the implementation guidance.

2. The proposed guidance does not explicitly address emergent conditions. Let us assume that a risk assessment, as proposed in the guidance, was performed and was concluded that barriers x and y can be removed to perform maintenance without declaring the supported systems inoperable for up to 30 days. Let us also assume that during the time interval when barriers x and y are removed, a train of an important system (perhaps the redundant train of a system whose second train is protected by a removed barrier) is found to be unavailable. Under these conditions it is quite likely that the plant risk would increase significantly. Clear guidance is needed to address situations like this in a timely manner. For how long would the plant continue to operate with degraded barriers without declaring the supported systems inoperable and on what basis?

3. The proposed guidance considers only the risk associated with the degraded barriers in the maintenance rule (MR) 10 CFR 50.56 (a)(4) criteria instead of the total configuration risk. Please explain the basis.

4. Guidance for treating the impact of external events on equipment supported by degraded barriers (e.g., tornados and external flooding) is needed.

5. The proposed guidance relies significantly on the results of quantitative risk assessments for decision making. However, it is stated that qualitative or blended risk assessments can also be used, as in MR 10 CFR 50.56 (a)(4) guidance, to implement the proposed LCO 3.0.9. Guidance is needed on how to use qualitative or blended risk assessments to ensure that the proposed LCO 3.0.9 will be implemented safely.

6. The definition of a barrier at the system train level by initiating event (page 7), is appropriate. According to this definition, LCO 3.0.9 allows up to 30 days before declaring the LCOs for the supported (protected) systems, independently of how the train barrier is degraded. In other words, LCO 3.0.9 requires that the degradation of elementary barriers (e.g., doors, curbs and installed barriers), which make up a train barrier for an initiating event, should not (collectively) last more than 30 days every time LCO 3.0.9 is used without declaring the supported systems LCOs. This clarification should be included in the implementation guidance.

7. TSTF-427 does not list any safety benefits of the proposed LCO 3.0.9. Please provide this information with discussion and examples, as appropriate.

Enclosure 1

8. TSTF-427 does not provide any background information regarding the treatment of barriers, including the impact of their degradation on operability requirements for supported systems, in the technical specifications and other applicable regulations.

This information is needed to establish the starting point of the proposed TS change and use it to assess its risk impact. Please provide this information.

Specific

1. On page 3, it is stated: Another important consideration is the capability of the plants PRA and configuration control tool. Plants with more sophisticated models and tools can make greater use of flexibility afforded by the Technical Specification initiatives.

What is meant by greater use of flexibility for plants with sophisticated models and what will be the use for plants with less sophisticated models? Guidance is needed to clarify how this statement will be implemented with the proposed LCO 3.0.9 on barriers.

2. The reviewers note, on the top of page 6, needs clarification. It states that LCO 3.0.9 may be expanded to other initiating event categories provided plant-specific analysis demonstrates that the frequency of the additional initiating events is bounded by the generic analysis.... How can an initiating event frequency be bounded by the generic risk analysis? Please clarify.

3. On pages 7 and 8, it is stated: For BWRs.....The ECCS, as a whole, not HPSI or HPCS system alone, must meet the single failure criterion. Thus, for the purposes of this initiative, LCO 3.0.9 can be used on single train systems when a separate diverse method to achieve the same safety function exists. The BWR ECCS single train high pressure systems (HPCI, HPCS, RCIC) are considered to be functionally redundant with ADS and low pressure systems. The staff believes that the guidance for allowing the plant to operate with degraded barriers for up to 30 days, without declaring the supported system LCOs, should be based on the assurance of low risk impact and defense-in-depth considerations and not just on whether the single failure criterion is met. Thus, it seems reasonable to be able to use LCO 3.0.9 on single-train redundant systems performing the same function, such as RCIC and HPCI, assuming it is not used on both simultaneously or when one of them is unavailable (this would not provide adequate defense-in-depth for some accidents, such as loss of offsite power with station blackout, even though redundant low pressure systems are available). In any case, the LCO 3.0.9 requirements for allowing degraded barriers should not be more relaxed than TS requirements governing simultaneous (supported) equipment outages. Please clarify and further justify your statement in light of these staff comments.

4. On page 8, it is stated that TSTF-427 ........requires some modification of the applicability of the current (a)(4) program. Several generic statements are made about the needed modification of the current (a)(4) program. Please clarify the following:

S It is stated that the rigor of licensee risk assessment programs and, thus, the ability to address the risk impact of multiple combinations of degraded barriers ...should be considered, and, as appropriate restrictions may need to be placed on the use of this initiative. This includes limiting the use of the barrier initiative to a reasonable number of degraded barriers at a given time, such that combinations of barriers/initiators are capable of being addressed by the risk assessment and

management tool. Although the staff agrees, in principle, with this statement, it must be pointed out that a process needs to be developed that will identify such appropriate restrictions and will provide guidance on using these restrictions in conjunction with the proposed LCO 3.0.

S It is stated that licensees must commit to the guidance of NUMARC 93-01, Section 11.......and that alternative methods ....are not used. Please explain what is the objective of such a commitment.

S A quote from NUMARC 93-01 Section 11.3.2.6 is stated, regarding the consideration of plant alterations (e.g., removal of barriers) in risk assessments, to show that written guidance in 10 CFR 50.65(a)(4) exists for the removal of barriers.

Although the staff agrees, in principle, with this observation, we would like to point out that the proposed TS change theoretically allows (based on the results of risk assessment) a large number of degraded barriers for up to 30 days before declaring the LCOs for the supported (protected) systems. This new allowance could introduce significant additional risk that must be properly assessed and managed. Therefore, the proposed implementation guidance should provide assurance that controls will be in place to ensure that the plant risk would not increase unacceptably. In addition, it must be shown that any risk increase will be consistent with guidance provided in risk-informed regulatory guides (e.g.,

RG 1.177 and RG 1.174) when the allowance is implemented in accordance with the proposed implementation guidance.

S Item 2, on page 9, states: For implementation of this initiative, the plant Maintenance Rule program and procedures will need to be revised to ensure that the risk assessment and management process is used whenever a barrier.....is considered degraded.... It is not clear why and how the Maintenance Rule program will need to be revised. What is the risk assessment and management process you are referring to in this statement? Please clarify.

5. On page 9, it is stated: A comprehensive listing of plant barriers and their design basis function is not required to implement this initiative as the risk analysis can be performed for degraded barrier(s) on a case-by-case basis. However, if one is available, it will save the licensee time in the performance of the risk assessment. An implicit assumption in this statement is that licensees have (and will take) adequate time to accurately verify the design basis function of barriers before they are removed for maintenance. This has the potential for errors that could impact the risk-informed decisionmaking process. Therefore, at a minimum, licensees should have a list of barriers protecting risk-important equipment, their associated design basis function(s) and potential interactions among equipment supported by the removed barriers. Please discuss.

6. On page 9, it is stated: It is expected that consideration of the risk impacts of using LCO 3.0.9 will generally be performed qualitatively, or through a combination of quantitative and qualitative methods. However, the process for assessing the acceptability of using the degraded barrier allowance, as outlined in Section 6.2 and the flowcharts of Figures 2 and 3, relies significantly on the results of quantitative risk assessments for decision making. The staff believes that guidance is needed on how to

use qualitative or blended risk assessments to ensure that the proposed LCO 3.0.9 will be safely implemented. In particular, this guidance should outline a process for using the action thresholds based on qualitative considerations discussed in NUMARC 93-01, Section 11, to assess the acceptability of the LCO 3.0.9 degraded barrier allowance. This guidance should be documented in a TSTF-427 revision together with a discussion demonstrating (using examples, if appropriate) that such guidance has incorporated adequate controls to provide confidence that the proposed time allowance for degraded barriers would be implemented safely (e.g., in accordance with guidance provided in applicable regulatory guides, such as RG 1.177 and RG 1.174).

7. On page 10 it is stated that a simple screening evaluation for multiple systems may be employed as the first step to determine the overall risk importance of the system or combination of systems to which the allowance would be applied at a given time. Could this simple screening evaluation be expanded, by considering a bounding initiating event frequency (sum of frequencies of all possible initiators associated with the degraded barrier), to a general bounding simplified approach that would be used for risk-informed decisionmaking when LCO 3.0.9 is implemented? Please discuss.

8. There is some inconsistent and confusing terminology in Section 6.2 where the process for assessing the risk impact of LCO 3.0.9 is discussed. For example, the words system and train are used interchangeably. Also, the word barrier is used for both elementary barriers (e.g., doors, curbs and installed barriers) and train barriers which are made up of several elementary barriers. Please clarify.

9. On page 18, the initiating event categories associated with LCO 3.0.9 barriers are listed.

Please provide typical frequency values and related key assumptions made in assessing these frequencies.

10. On page 19, guidance on determining and using risk achievement worth (RAW) values is discussed. Please provide typical RAW values (on a ratio scale) of safety system trains at representative PWR and BWR plants.

11. On page 19 it is stated: If there is very little or no interaction between the affected components or systems, the RAW values can be summed ........ Please explain what is meant by very little or no interaction and provide proof that this statement is valid generically.

12. On page 22 it is stated: There may be other similar processes based on RG 1.182 and NUMARC 93-01 that define risk management actions and determine acceptable time frames, such as those that result in colors or use other defense-in-depth methods to define specific risk levels and risk management actions. The staff does not disagree, in principle, with the use of other similar processes based on NUMARC 93-01 as long as such processes will follow the staff approved implementation guidance. Please explain, by using an example, if necessary, the process of using defense-in-depth methods to define specific risk levels and determine acceptable time frames.

13. On page 23 it is stated: Documentation of each individual use of the risk assessment and risk management actions for use of LCO 3.0.9 is not explicitly required by the NRC.

However, it may be prudent to document these activities for internal reasons........

Although no explicit documentation of 50 CFR50.56 (a)(4) risk assessments is required, this does not mean that no documentation will be necessary when the proposed LCO 3.0.9 is implemented. Since this new allowance could introduce significant additional risk, the decision making approach should include controls which will provide assurance that this risk will be properly assessed and managed. The documentation of the specific degraded barriers, their protective function(s) and affected equipment, and the associated risk-informed justification could be one of the controls in place to ensure that LCO 3.0.3 will be implemented safely. Please discuss.

14. On page A-1 it is stated that the colors are determined from the RAW value. This conflicts the summary table reported in page A-5. It appears that only the Green color is determined by the RAW value. The other colors are determined by the conditional CDF value. Since the RAW value (on a ratio scale) is linked to a plants base CDF, which varies from plant to plant, the staff believes that all colors should ultimately be determined by the CDF value and not by the RAW value. For example, for a plant with base CDF of 2E-4/year, a RAW of 1.9 implies a conditional CDF of 3.8E-4/year. In this case, according to the criteria listed in the summary table of page A-5, the color is both Green (RAW less than 2) and Orange (CDF greater than 2.5E-4/year but less than 1E-3/year). Please discuss.

15. Appendix A discusses an example of a risk assessment and management program, which uses a matrix process with pre-solved configurations, involving both single and multiple equipment being affected by degraded barriers. The staff review identified the following areas that need clarification or more detailed discussion:

S On page A-1 it is stated: The first step in quantifying the PRA matrix is to determine the CDF1 for the single TS component....... and the CDF2 for combinations of TS equipment (i.e., one degraded barrier impacts two TS systems/functions). The explanation in parenthesis is confusing. Is there any reason for stating that one degraded barrier impacts two TS systems as opposed to two degraded barriers each impacting one TS system? Please clarify.

S In the second paragraph of page A-3 it is stated: The CDF value of 2.5E-4/yr is shown in Table A-4 and is based on the time it takes to reach an ICDP of 1E-6.

This time period corresponds approximately to 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />...........If the CDF value is shown not to exceed 2.5E-4/yr then the risk increase while the barrier is removed is minimal. How was the 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> time period estimated? It appears that this value conflicts the allowed times reported in Table A-6. Why is not the equation of page A-5 used to assess the time it takes to reach an ICDP of 1E-6? Also, please explain why the risk increase is minimal if the CDF value is shown not to exceed 2.5E-4/yr.

S It is stated that no removal of barrier(s) is allowed, without entering the supported systems LCOs, when the conditional CDF (obtained by assuming that the protected equipment by the degraded barrier(s) are unavailable) is higher than 1E-3/year. However, it appears that this statement conflicts some of the calculated

allowed times reported in Table A-6. For example, an allowed time of six days is shown in Table A-6 for the case of a barrier impacting both the 4.16 kV essential power and the AFW turbine-driven pump, a case with a conditional CDF of about 7E-3/year. Please clarify.

16. Recommend the following addition, denoted by italics, to the last sentence of the proposed LCO 3.0.9: At the end of this time, up to a maximum of 30 days, the barriers must be ....

17. Recommend the following additions, denoted by italics, to the proposed the Bases of LCO 3.0.9:

- Change the first sentence of the Bases to read, LCO 3.0.9 establishes that, under certain conditions, systems ....

- Change the last sentence of the second Bases paragraph to read, If the time allowance, up to a maximum of 30 days, expires ....

TSTF-426 REQUEST FOR ADDITIONAL INFORMATION General Comments:

16. The intent of Topical Report WCAP-16125-NP was to provide 1) a risk-informed justification for delaying entry into LCO 3.0.3 for specific technical specification systems with explicit LCO 3.0.3 entry requirements (Initiative 6.c), and 2) a risk-informed justification for adding conditions to specific LCOs where conditions currently do not exist and require default entry into LCO 3.0.3 (Initiative 6.b). WCAP-16125-NP specifically states on page 1 that the intent of these modifications is to provide a risk-informed alternative to the current LCO 3.0.3 requirements such that the plant staff has adequate time to resolve a significant loss of function while the plant remains operating.

Resolving the issue while the plant is at power is often the lowest risk state. In those rare instances where a repair at power is attempted but is unsuccessful, and a delayed shutdown is still required, the additional planning time will reduce risks during plant transition while incurring negligible incremental risks to the public health and safety.

TSTF-426 proposes to delete Required Actions for entrance into LCO 3.0.3 for the technical specifications covered in the topical report. The staffs safety evaluation did not approve the deletion of these Required Actions, only a risk-informed delayed entry into LCO 3.0.3. This change needs to be justified to be acceptable.

Tech Spec Specific Comments:

17. TS 3.5.1 has an explicit LCO 3.0.3 entry requirement (STS Condition D) when two or more Safety Injection Tanks (SITs) are inoperable. The topical report requested and the staff safety evaluation approved the revision to Condition D to allow 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore one SIT to operable. The topical report states on page 42 that At the end of this period, the operator will be instructed to exit the LCO via resolution of the problem, or take actions to bring the plant to hot shutdown. The staff safety evaluation states, under proposed modification, that the proposed change is to increase the time available to restore one SIT before entry into LCO 3.0.3 to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. However, TSTF-426 proposes to delete the requirements to enter LCO 3.0.3 and reverse Conditions C and D. As such, if the Required Actions and associated Completion Times of any Actions are not met, the plant must be in MODE 3 in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and the pressure must be reduced to < [700] psia within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in order to exit the Applicability of the TS. TSTF-426 did not provide justification for the deletion of the Required Action to enter LCO 3.0.3 or the proposed change in shutdown end state (MODE 3 with pressure < [700] psia versus MODE 5). Provide adequate justification.

18. TS 3.5.2 currently requires two ECCS trains to be OPERABLE. STS Condition B which requires the restoration of one or more trains to OPERABLE status in 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is replaced by three subsystem condition statements (Conditions B, C, and D). Conditions B and D are discussed in the topical report and the staffs safety evaluation and are acceptable. Proposed Condition C addresses the inoperability of one HPSI subsystem with a completion time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. This new condition is consistent with the intent and completion time of current STS Condition B and is acceptable.

Enclosure 2

a. However, both the topical report and TSTF-426 proposed to delete existing STS Condition D which requires immediate LCO 3.0.3 entry when less than 100% of the ECCS flow equivalent to a single OPERABLE train is available. This proposed change was not accepted by the staff because an adequate basis was not provided for the deletion of STS Condition D. Page 33 of the staffs safety evaluation provides specific guidance on what information the WOG needs to address to justify this change. This justification was not provided in TSTF-426 and is not acceptable.

b. With the proposed changes discussed above, TSTF-426 proposes that existing STS Condition C, which requires the plant be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and reduction in pressurizer pressure to < [1700] psia within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if the Required Action and associated Completion Time not met, be revised to become Condition E. The topical report does not discuss this change (besides listing it on the table) and therefore it was not addressed as part of the staffs review. In addition, TSTF-426 does not provide any justification for the proposed change. This change is also not acceptable without further justification.

19. TS 3.6.6A and 3.6.6B have explicit LCO 3.0.3 entry requirements when two containment spray trains inoperable OR any combination of three or more trains inoperable (Condition G of TS 3.6.6A) or any combination of three or more trains inoperable (Condition G of TS 3.6.6B). TSTF-426 proposes to delete Condition G in both TS 3.6.6A and 3.6.6B. Both the topical report (Table 5.2.3-2) and TSTF-426 propose to revise the shutdown modes to MODE 3 in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and MODE 5 in 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. However, the staffs safety evaluation specifically stated that this proposed change is not justified in the topical report and not acceptable without further justification (see page 38).

TSTF-426 did not provide adequate justification for this proposed change and therefore the proposed deletion of Condition G in TS 3.6.6A and 3.6.6B is not acceptable. In particular, TSTF-426 deletes the Condition statements that address any combination of three ... trains inoperable, which if not included will illogically result in the TS allowing additional time for four trains inoperable, but require an immediate LCO 3.0.3 entry for three trains inoperable.

20. TSTF-426 identifies an editorial change to TS 3.6.10. This LCO requires [Two] ICS trains to be OPERABLE. TSTF-426 states that the brackets around Two are removed.

However, the STS markups do not show this change. In fact, new Condition B also has the brackets around Two. New Condition B states [Two] ICS trains inoperable. If the proposed editorial change is to be made, the STS should be marked up appropriately.

The proposed editorial change is also applicable to the new Condition B.

21. TS 3.7.11 has, as Condition F, explicit LCO 3.0.3 entry requirements when two CREACS trains are inoperable in MODE 1, 2, 3, or 4 for reasons other than Condition B.

The staffs safety evaluation for the RMTS Initiative 6 topical report states specifically that the proposed end state change to MODE 4 does not apply to Condition F. WCAP-16125-NP does not provide justification for modifying the Required Action from Enter LCO 3.0.3" to an end state of MODE 4.

However, TSTF-426 proposed the following: Condition F is revised to require restoring one CREACS train to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and moves Condition F to

Condition C. Existing Condition C, now Condition D, which requires entering Mode 3 in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and Mode 5 in 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />, is modified to apply to the new Condition C. TSTF-426 continues to state that The Topical Report also justified a change in the end state from Mode 5 to Mode 4. This end state change was included in TSTF-422 and is, therefore, not included in this Traveler.

TSTF-422 proposes to change the end state for existing Condition C, which is not applicable to Condition F. The staff did not approve the end state change as proposed in the topical report for Condition F. As such, the proposed changes to TS 3.7.11 (except for the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> completion time in Condition F) are not acceptable without further justification.

22. TS 3.7.12 Condition E requires entering LCO 3.0.3 immediately when two CREATCS trains are inoperable. TSTF-426 proposes similar changes to TS 3.7.12 as those discussed in RAI 6. Similar to the discussion above, the staffs safety evaluation states that the proposed change to allow MODE 4 as the final end state is not justified in the topical report and is not acceptable. TSTF-426 did not provide any justification for the proposed end state change. In addition, TSTF-422 proposes to change the end state for existing Condition B which is not applicable to TSTF-426. Therefore, the proposed changes to TS 3.7.12, except for the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> completion time to Condition E, are not acceptable without further justification.