NOC-AE-03001657, Proposed Emergency Change to Technical Specification 3.8.1.1, Note 12

Proposed Emergency Change to Technical Specification 3.8.1.1, Note 12

ML033640261
Person / Time
Site:	South Texas
Issue date:	12/27/2003
From:	Parkey G South Texas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NOC-AE-03001657, STI: 31682779, TAC MC1616
Download: ML033640261 (18)

Text

December 27, 2003 NOC-AE-03001657 10CFR50.90 U. S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852 South Texas Project Unit 2 Docket No. STN 50-499 Proposed Emergency Change to Technical Specification 3.8.1.1 Note 12

Reference:

1. Letter from T. J. Jordan to NRC Document Control Desk dated December 15, 2003, Proposed Emergency Change to Technical Specification 3.8.1.1 (NOC-AE-03001647)

2. Letter from T. J. Jordan to NRC Document Control Desk dated December 18, 2003, Supplement 1 to Proposed Emergency Change to Technical Specification 3.8.1.1 (NOC-AE-03001650)

3. Letter from T. J. Jordan to NRC Document Control Desk dated December 20, 2003, Revision to Proposed Emergency Change to Technical Specification 3.8.1.1 (NOC-AE-03001653)

4. Letter from T. J. Jordan to NRC Document Control Desk dated December 23, 2003, Proposed Emergency Change to Technical Specification 3.8.1.1 to Support Diesel Generator Inspections (NOC-AE-03001656)

5. Letter from David Jaffe, NRC, to J. J. Sheppard, STPNOC, dated December 23, 2003, South Texas Project, Unit 2 - Issuance of Amendment Concerning One-Time Allowed Outage Time Extension for No. 22 Emergency Diesel Generator (TAC No MC1616)

In References 1 - 4, STP Nuclear Operating Company (STPNOC) requested an emergency amendment to the STP Unit 2 Operating License NPF-80. The proposed changes to the Technical Specifications (TS) would revise TS 3.8.1, AC Sources - Operating, to permit a one-time extension of the allowed outage time (AOT) for Unit 2 Standby Diesel Generator (SDG) 22 from 14 days to complete repairs on the SDG. Reference 5 approved a one-time extension of the SDG 22 AOT to 21 days to support inspections of the other two Unit 2 SDGs. However, that AOT extension does not provide time to complete repairs on SDG 22.

This submittal supersedes the changes proposed in Reference 3 for a one-time extension of the AOT to 113 days to complete the repairs on SDG 22, although the technical basis and compensatory actions described in Reference 3 still apply and are referenced in the attachments. The total AOT proposed in this submittal is the same as that proposed in Reference 3 or 113 days. However, since STI: 31682779

NOC-AE-03001657 Page 2 of 4 the AOT was extended from 14 days to 21 days by References 4 and 5, the AOT extension is now 92 days instead of 99 days.

As described in Reference 3, STPNOC has determined that an extension of the SDG AOT to 113 days is necessary and can be justified. The proposed revised AOT extension meets the criteria of Regulatory Guide 1.174, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis and Regulatory Guide 1.182, Assessing and Managing Risk Before Maintenance Activities at Nuclear Power Plants.

with no additional compensatory measures beyond the actions required by the STP Configuration Risk Management Program (CRMP). However, as described in Reference 3, STPNOC will provide the additional compensatory action of incorporating temporary non-safety-related diesel generator capability.

As described in Reference 2, STPNOC determined that the cause of the SDG 22 failure is microcracks created on the master connecting rod during manufacturing that propagated due to high cycle fatigue until the master connecting rod failed. Reference 2 includes a detailed description of the STPNOC cause evaluation, potential for common mode failure, and a description of the inspections performed on the other SDG 22 connecting rods and on the connecting rods for the STP Unit 1 SDGs. Those inspections have been completed with no recordable indications. Consequently, STPNOC has determined there is no evidence of common mode failure.

To provide further confirmation that there is no potential for common mode failure, STPNOC will apply the 7 day AOT extension proposed in Reference 4 and approved by Reference 5 to inspect the connecting rods on the other two Unit 2 SDGs. This application is based on the assumption that the inspections of the other two Unit 2 SDGs will be successful such that there is clearly no potential for common cause. STPNOC will apprise the NRC of the results of the inspections.

Separate from this application, STPNOC is providing the following supplementary information to support the proposed amendment:

• The inspection results for SDG 21 and SDG 23

• Stress analysis evaluation for justifying NDE inspection intervals

• NDE process calibration standard photographs The AOT for SDG 22 expires on December 30, 2003. As described in Reference 3, the repair of SDG 22 may take up to 113 days from the time the SDG failed. Consequently, extension of the SDG 22 AOT beyond the 21 days approved in Reference 5 is required.

Prompt approval of the proposed license amendment is needed to avoid a potential shutdown in accordance with TS 3.8.1.1 at the expiration of the AOT, which would require STP Unit 2 to be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Therefore, STPNOC requests approval of this license amendment request on an emergency basis and issuance of the amendment no later than December 29, 2003 to allow implementation prior to expiration of the AOT on December 30, 2003.

NOC-AE-03001657 Page 4 of 4 cc:

(paper copy) (electronic copy)

Bruce S. Mallett A. H. Gutterman, Esquire Regional Administrator, Region IV Morgan, Lewis & Bockius LLP U. S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 L. D. Blaylock Arlington, Texas 76011-8064 City Public Service U. S. Nuclear Regulatory Commission David H. Jaffe Attention: Document Control Desk U. S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike R. L. Balcom Rockville, MD 20852 Texas Genco, LP Richard A. Ratliff A. Ramirez Bureau of Radiation Control City of Austin Texas Department of Health 1100 West 49th Street C. A. Johnson Austin, TX 78756-3189 AEP Texas Central Company Jeffrey Cruz Jon C. Wood U. S. Nuclear Regulatory Commission Matthews & Branscomb P. O. Box 289, Mail Code: MN116 Wadsworth, TX 77483 C. M. Canady City of Austin Electric Utility Department 721 Barton Springs Road Austin, TX 78704

NOC-AE-03001657 Attachment 1 Page 1 of 9 Attachment 1 Description of Changes and Safety Evaluation 1.0 Description Pursuant to 10 CFR 50.90 and 10 CFR 50.91(a)(6), STP Nuclear Operating Company (STPNOC) requests an emergency amendment to the STP Unit 2 Operating License NPF-80.

The proposed change to the Technical Specifications (TS) would revise TS 3.8.1, AC Sources - Operating, to extend the allowed outage time (AOT) for Unit 2 Standby Diesel Generator (SDG) 22 from 21 days to 113 days. STPNOC is proposing this as a one-time change.

During a surveillance test on December 9, 2003, SDG 22 experienced a failure and STPNOC will not be able to complete the repairs in the current 21day AOT. The maintenance activities are being worked on a 24-hour per day schedule until completed.

Emergency approval of the proposed license amendment is needed to avoid a potential shutdown in accordance with TS 3.8.1 at the expiration of the AOT on December 30, 2003. Action 3.8.1.1.b would require STP Unit 2 to be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

STPNOC could not reasonably have foreseen or anticipated the failure of SDG 22.

Therefore, STPNOC requests approval of this license amendment request on an emergency basis and issuance of the amendment no later than December 29, 2003 to allow implementation prior to expiration of the AOT on December 30, 2003.

This license amendment request is a risk-informed licensing change. The proposed change meets the criteria of Regulatory Guide RG 1.174, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis and Regulatory Guide 1.182, Assessing and Managing Risk Before Maintenance Activities at Nuclear Power Plants.

2.0 Proposed Change The proposed change revises Note 12 for TS 3.8.1.1.b, TS 3.8.1.1.c, and TS 3.8.1.1.f to permit a one-time extension to the AOT for SDG 22 from 21 days to 113 days from its failure on December 9, 2003, as shown below.

(12)

For the Unit 2 Train B standby diesel generator (SDG 22) failure of December 9, 2003, restore the inoperable standby diesel generator to OPERABLE status within 113 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

NOC-AE-03001657 Attachment 1 Page 2 of 9 3.0 Background 3.1 Electrical Power Systems On-site AC Sources Description See Reference 3 of the cover letter.

3.2 Past Performance See Reference 3 of the cover letter 3.3 SDG 22 Failure See Reference 2 and Reference 3 of the cover letter.

Based on the evaluations described Reference 2 and Reference 3 of the cover letter, STPNOC concluded there was no potential for common cause failure. To provide further confirmation that there is no potential for common mode failure, STPNOC will apply the 7 day AOT extension proposed in Reference 4 and approved by Reference 5 of the cover letter to inspect the connecting rods on the other two Unit 2 SDGs and apprise the NRC of the results of the inspections.

If STPNOCs conclusions regarding common mode failure change prior to approval of this amendment, STPNOC will promptly advise the NRC and withdraw the proposed amendment. If the conclusions change subsequent to issuance of the amendment, STPNOC will promptly evaluate the operability of the potentially affected SDGs and apply the requirements of the Technical Specifications.

4.0 Technical Analysis 4.1 Electrical Power Systems AC Sources Safety Analysis Basis See Reference 3 of the cover letter.

4.2 Deterministic Evaluation (Defense in Depth and Safety Margins)

See Reference 3 of the cover letter.

4.3 Probabilistic Risk Assessment (PRA) Evaluation The PRA description and evaluation is provided in Reference 3 of the cover letter.

The risk for the proposed AOT extension in this application is for 92 days because it begins after the 7 day AOT extension approved in Reference 5 of the cover letter has ended. The calculation in Reference 3 was for 99 days.

NOC-AE-03001657 Attachment 1 Page 3 of 9 Regulatory Guide 1.174 Evaluation Because the SDG 22 condition is limited in time, the delta CDF and the delta LERF are multiplied by the expected 92-day extension of the AOT to obtain a conditional probability. The conditional probability is treated as an Incremental Conditional Core Damage Probability (ICCDP) and Incremental Conditional Large Early Release Probability (ICLERP) for the evaluation against RG 1.174. The PRA evaluation for extending the AOT an additional 92 days was performed assuming zero maintenance (except for required TS surveillances which render equipment non-functional) for that time.

The table below depicts the acceptance criteria of RG 1.174 and the results calculated for the proposed change. Attachment 4 provides a breakdown of the change in risk levels for each planned surveillance during the proposed AOT.

ICCDP Total CDF ICLERP Total LERF STP Unit 2 before - 9.1E-06/yr - 5.2E-07/yr proposed change Results with 92 6.2E-06 1.5E-05/yr 4.3E-07 9.4E-07/yr days additional SDG 22 AOT RG 1.174 Criteria >1.0E-06 <1.0E-04/yr. >1.0E-07 <1.0E-05/yr

<1.0E-05 <1.0E-06 These values are within the criteria established in RG 1.174.

RG 1.182 Evaluation RG 1.182 and RG 1.160 are used in conjunction with NUMARC 93-01 as standards for implementation of 10CFR50.65 (Maintenance Rule). Section 11.3.7.2 of NUMARC 93-01 includes recommended quantitative risk action thresholds for maintenance activities, as reproduced in the table below.

NOC-AE-03001657 Attachment 1 Page 4 of 9 Incremental Incremental [Conditional]

[Conditional] Core Large Early Release Damage Probability Probability (ICLERP)1 (ICCDP)1

> 1E-05 Configuration should not > 1E-06 normally be entered voluntarily 1E 1E-05

• Assess non- 1E 1E-06 quantifiable factors

• Establish risk management actions

< 1E-06 Normal work controls < 1E-07 Note 1: For clarity and consistency of terms, the term conditional is added to the table heading. The calculated ICDP includes the quantified effect of the maintenance configuration (condition).

The ICCDP for the proposed change is 6.2E-06, which is within the 1E 1E-05 range and the ICLERP for the proposed change is 4.3E-07, which is within the 1E 1E-06 range. Attachment 4 provides a breakdown of planned surveillance activities that would render equipment non-functional during the proposed AOT. As described in Section 4.4 of this application, STPNOC will address the non-quantifiable factors and establish risk management actions.

PRA Evaluation Conclusions The final results of the risk evaluation were compared with the risk significance criteria from RGs 1.174 and 1.182. The calculated values for ICCDP and ICLERP demonstrate that the proposed SDG 22-completion time change has an acceptably small quantitative impact on plant risk.

Station risk levels remain low (near baseline values) and manageable with sufficient margin to allow remedial and corrective actions to be implemented in the event unplanned equipment outages occur. Therefore, it is concluded that, based on the small quantitative plant risk impact and the compensatory measures described in Sections 4.4 and 4.5, the risk associated with the SDG 22 outage does not impose a significant risk to public health and safety.

4.4 Risk Management, Including Compensatory Actions and Consideration of Non-quantifiable factors See Reference 3 of the cover letter. In addition to the risk management actions described in Reference 3, the compensatory actions for unplanned entry into extended AOTs for SDGs are repeated below. Compensatory action 4 is modified (see the underlined words) from that described in Reference 3 in view of the duration of the proposed EAOT.

NOC-AE-03001657 Attachment 1 Page 5 of 9

1. Notification of the transmission/distribution service providers (TDSP) of the condition and of the maintenance restrictions required for the STP switchyard.

2. Hang EAOT protected train signs.

3. Planned maintenance on required systems, subsystems, trains, components, and devices that depend on the other trains of equipment during the EAOT SHALL NOT be performed.

4. No planned maintenance that could result in an inoperable OPEN containment penetration.

5. Containment purges shall be for pressure control only and for short duration.

6. No planned maintenance on the Unit 2 Technical Support Center Diesel Generator.

7. No planned maintenance on Load Center 2W.

8. No planned maintenance on Motor Control Center 2G8.

9. No planned maintenance on the Positive Displacement Charging Pump (PDP).

10. No planned maintenance on the Emergency Transformer or the 138KV Blessing to STP and Lane City to Bay City lines.

11. No maintenance activities in the switchyard that could directly cause a Loss of Offsite Power event unless required to ensure the continued reliability and availability of the offsite power sources.

12. No planned maintenance on the turbine-driven auxiliary feedwater pump.

13. Attempt to VERIFY that the station is not under hurricane, tornado, or flood watches or warnings. (Note that weather was addressed earlier in this application and no severe weather is currently forecast.)

14. Attempt to VERIFY with the TDSP that no adverse weather conditions exist in the areas of our offsite power supplies that challenge the stability of grid.

15. ENSURE the Work Schedule contains no planned maintenance on Switchgear 2L or 2K.

4.5 Non-Safety-Related Diesel Generator (NDG) Capability Reference 3 of the cover letter provides a description of the NDG capability.

PRA Analysis of Temporary Diesel Generator Capability The use of the NDGs can be explicitly credited in STPs PRA for this issue. The NDGs are assumed to provide power to Unit 2 B Train components in the event of a Loss of Offsite Power (LOOP). The NDGs have arrived on site with installation activities in progress, but for the PRA analysis they are assumed to be available on January 15, 2004. The NDGs are conservatively not being credited for safety injection (SI) conditions (i.e., LOCAs, Steam Generator Tube Ruptures, and Steam Line Breaks).

NOC-AE-03001657 Attachment 1 Page 6 of 9 The capabilities of the NDGs are such that the essential equipment for supporting safe reactor shutdown is fully supported. The external events included in the PRA that affect the plant switchyard are also assumed to affect the NDGs. These include external floods, seismic events, and high winds. For external floods, the NDGs are not credited in the most severe cases, which are the loss of the main coolant reservoir impoundment in differing locations. For seismic events, the NDGs are not credited with the same level of robustness as the SDGs. The NDGs are assumed to fail with the same likelihood as the electric grid. It is also important to note that unlike the permanent SDGs, the NDGs are not dependent upon essential cooling water for cooling. The NDGs are stand-alone devices with all support functions resident with the NDG itself. The PRA was modified to remove the essential cooling water system dependency from the Train B components in the event of a LOOP for the time duration that the NDG is present and functional. The LOOP event initiators where the NDGs are credited is for both internally initiated LOOP scenarios (i.e., transient induced) and externally initiated LOOP scenarios. Since the NDGs are credited to support only LOOP scenarios and not SI scenarios, automatic actuation of the NDGs in prescriptive timeframes is not required (i.e., manual operator action is adequate).

For purposes of the analysis, an NDG failure rate of 0.1 and an operator action failure rate of 0.1 is considered appropriate and conservative.

The NDGs, when installed, will substantially restore STPs original levels of defense-in-depth for LOOP scenarios and provide a significant decrease in station risk levels (i.e., ICCDP and ICLERP) for the SDG 22 outage.

ICCDP Total CDF ICLERP Total LERF STP Unit 2 before - 9.1E-06/yr - 5.2E-07/yr proposed change Results with 92 6.2E-06 1.5E-05/yr 4.3E-07 9.4E-07/yr days additional AOT without credit for temporary diesel power Results with 1.2E-06 1.0E-05/yr 8.6E-08 6.0E-07/yr credit for temporary diesel power RG 1.174 Criteria >1.0E-06 <1.0E-04/yr. >1.0E-07 <1.0E-05/yr

<1.0E-05 <1.0E-06

NOC-AE-03001657 Attachment 1 Page 7 of 9 5.0 Regulatory Analysis 5.1 No Significant Hazards Consideration In 10 CFR 50.92©, the Nuclear Regulatory Commission (NRC) provides the following standards to be used in determining the existence of a significant hazards consideration:

a proposed amendment to an operating license for a facility licensed under 50.21(b) or 50.22, or for a testing facility involves no significant hazards consideration, if operation of the facility in accordance with the proposed amendment would not: (1) Involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) Create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) Involve a significant reduction in the margin of safety.

STPNOC has reviewed the proposed amendment request and determined that its adoption does not involve a significant hazards consideration based as discussed below.

1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

SDG 22 provides onsite electrical power to vital systems should offsite electrical power be interrupted. It is not an initiator to any accident previously evaluated.

Therefore, this extended period of operation with the SDG out-of-service will not increase the probability of an accident previously evaluated.

The SDGs act to mitigate the consequences of design basis accidents that assume a loss of offsite power. For that purpose, redundant SDGs are provided to protect against a single-failure. During the Technical Specification 14 day allowed outage time, an operating unit is allowed by the Technical Specifications to remove one of the SDGs from service, thereby losing this single-failure protection. This operating condition is considered acceptable. The consequences of a design basis accident coincident with a failure of the redundant SDG during the extended allowed outage time are the same as those during the 14-day allowed outage time. Therefore, during the period of the extended AOT, there is no significant increase in consequences of an accident previously evaluated.

Therefore, the proposed change will not involve significant increase in the probability or consequences of an accident previously evaluated.

NOC-AE-03001657 Attachment 1 Page 8 of 9

2. Does the proposed change create the possibility of a new or different accident from any accident previously evaluated?

Response: No.

There are no new failure modes or mechanisms created due to plant operation for an extended period to perform repairs and post-maintenance testing of SDG 22.

Extended operation with an inoperable SDG 22 does not involve any modification in the operational limits or physical design of plant systems. There are no new accident precursors generated due to the extended allowed completion time.

Therefore, the proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No.

Plant operation for the proposed extension of the existing AOT for inoperable SDG 22, has been shown to have a very small impact on plant risk using the criteria of RG 1.174 and RG 1.182. During the extended allowed outage time, the electrical power system maintains the ability to perform its safety function of providing an available source of power to the Engineered Safety Feature (ESF) systems as assumed in the accident analyses. During the extended maintenance and test period, appropriate compensatory measures will be implemented to restrict risk significant activities.

Therefore, the proposed change does not involve a significant reduction in a margin of safety as defined in the basis for any Technical Specification.

5.2 Applicable Regulatory Requirements/Criteria With the implementation of the proposed change, STP Unit 2 continues to meet applicable design criteria. The proposed change is a one-time extension to the TS AOT. It does not affect the design basis of the plant. In addition, STP Unit 2 will remain within the scope of the TS Limiting Conditions for Operation and is still subject to the requirements of the action statements as governed by 10CFR50.36.

STP Unit 2 meets the requirements of General Design Criterion 17 of Appendix A of 10CFR50 for Electric Power Systems. The design of the on-site power source is not changed by the extension to the AOT and compliance with the GDC is not affected.

The proposed change to extend a TS action does not alter the design basis for loss of all alternating current power governed by 10CFR50.63. In addition, although the normal design of STP Unit 2 is an alternate AC plant, the plant meets the requirements for a four-hour coping plant as described in Reference 2 of the cover letter.

NOC-AE-03001657 Attachment 1 Page 9 of 9 The proposed change to extend the TS action meets the criteria of RG 1.182 and 10CFR50.65 In conclusion, based on the deterministic and PRA considerations discussed in this submittal, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

6.0 Environmental Consideration STPNOC has evaluated the proposed changes and determined the changes do not involve (1) a significant hazards consideration, (2) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (3) a significant increase in the individual or cumulative occupational exposure. Accordingly, the proposed changes meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22©(9),

and an environmental assessment of the proposed changes is not required.

Attachment 2 Revised Technical Specification Page

TABLE 4.8-1 DIESEL GENERATOR TEST SCHEDULE (Not used)

SPECIFICATION NOTATIONS (1)

Loss of one 13.8 kV Standby Bus to 4.16 kV ESF bus line constitutes loss of one offsite source. Loss of two 13.8 kV Standby busses to 4.16 kV ESF bus lines constitutes loss of two offsite sources.

(2)

All diesel generator starts for the purpose of these surveillances may be preceded by a prelube period.

(3)

A diesel generator start in less than or equal to 10 seconds (fast start) shall be performed every 184 days. All other diesel generator starts for the purpose of this surveillance may be modified starts involving reduced fuel (load limit) and/or idling and gradual acceleration to synchronous speed.

(4)

Generator loading may be accomplished in accordance with vendor recommendations, including a warmup period prior to loading.

(5)

The diesel generator start for this surveillance may be a modified start (see SR 4.8.1.1.2a.2)).

(6)

Momentary transients outside this load range due to changing conditions on the grid shall not invalidate the test.

(7)

If Specification 4.8.1.1.2a.2) is not satisfactorily completed, it is not necessary to repeat the preceding 24-hour test. Instead, the standby diesel generator may be operated at 5000-5500 kW for a minimum of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> or until operating temperature has stabilized.

(8)

(Not used)

(9)

(Not used)

(10)

This test may be performed during power operation provided that the other two diesel generators are operable.

(11)

Credit may be taken for events that satisfy any of these Surveillance Requirements.

(12)

For the Unit 2 Train B standby diesel generator (SDG 22) failure of December 9, 2003, restore the inoperable standby diesel generator to OPERABLE status within 113 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

SOUTH TEXAS - UNITS 1 & 2 3/4 8-7 Unit 1 - Amendment No. 68, 122 Unit 2 - Amendment No. 57,110, 148

NOC-AE-03001657 Attachment 3 Attachment 3 Commitments In addition to the commitments listed in Reference 3 of the cover letter, the commitment below has been entered into the STP Corrective Action Program (CAP) for tracking. The CAP meets the requirements of NEI 99-04, Rev. 0, Guidelines for Managing NRC Commitment Changes.

There are no commitments other than the following in this letter:

• To provide further confirmation that there is no potential for common mode failure, STPNOC will apply the 7 day AOT extension proposed in Reference 4 and approved by Reference 5 of the cover letter to inspect the connecting rods on the other two Unit 2 SDGs and apprise the NRC of the results of the inspections. This will fulfill commitment number 2 in Reference 3.

Notes:

1. Commitment numbers 6 and 7 in Reference 3 are completed.

2. Commitment number 9 in Reference 3 is revised to read that the temporary non-safety-related diesel capability described in the letter dated December 20, 2003 (NOC-AE-03001653) will be available for use by January 15, 2004.

NOC-AE-03001657 Attachment 4 Page 1 of 2 Attachment 4 Risk Analysis of DG22 and Planned Surveillances During the time that DG 22 will be unavailable there will be the need to perform required surveillance tests. In most cases surveillance activities do not render the affected equipment non-functional in accordance with the CRMP procedure (0PGP03-ZA-0091). STP has reviewed the surveillances scheduled to be performed through the requested AOT extension and has determined that the following surveillances will render affected equipment non-functional:

Number Surveillance Name Surveillance Description These surveillances verify the Train R(S) Solid State Protection SP-0005R SSPS Logic Train R Functional Test System (SSPS) Automatic Trip and Automatic Actuation Logic output functions by simulating input combinations in conjunction SP-0005S SSPS Logic Train S Functional Test with each possible interlock.

SP-0006R Train R Reactor Trip Breaker TADOT These surveillances verify Reactor Trip Breaker R trips on demand from the Train R Solid State Protection System (SSPS) by simulating input trip logic and verifying the operation of SP-0006S Train S Reactor Trip Breaker TADOT Reactor Trip Breaker R (S).

SP-0007A SSPS Actuation Train A Master Relay Test SP-0007B SSPS Actuation Train B Master Relay Test These surveillances verify Actuation Train A (B, C) Master Relay output continuity and operability as required by the SP-0007C SSPS Actuation Train C Master Relay Test Technical Specifications SP-0008A SSPS Train A Slave Relay Test (Outputs Blocked)

SP-0008B SSPS Train B Slave Relay Test (Outputs Blocked) These surveillances partially verify Actuation Train A (B, C)

Slave Relay output contact continuity and operability as SP-0008C SSPS Train C Slave Relay Test (Outputs Blocked) required by Technical Specifications SP-0009A SSPS Actuation Train A Slave Relay Test SP-0009B SSPS Actuation Train B Slave Relay Test These surveillances verify Actuation Train A (B, C) Slave Relay Operability and output continuity as required by the Technical SP-0009C SSPS Actuation Train C Slave Relay Test Specifications SP-0010A Train A ESF Load Sequencer Manual Local Test These surveillances partially verify ESF Load Sequencer A (B, SP-0010B Train B ESF Load Sequencer Manual Local Test C) Output Relay and Actuation Train A (B, C) Slave Relay output continuity and operability as required by the Technical SP-0010C Train C ESF Load Sequencer Manual Local Test Specifications

NOC-AE-03001657 Attachment 4 Page 2 of 2 In accordance with the stations surveillance schedule, the following plant configuration states due to surveillance activities are expected to occur:

Test Surveillance Configuration Time Interval Duration Tests CRMP W/out SDG 22 Duration W/ NDG as of 1/15/04 12/30/03 to RAsCal 3/3104 Hrs 92 Days Designator ICCDP ICLERP Hrs ICCDP ICLERP 1/5/2004 3 SP-0007B ESFB 8.2E-09 5.8E-10 3 8.2E-09 5.8E-10 1/5/2004 3 SP-0008B ESFB 8.2E-09 5.8E-10 3 8.2E-09 5.8E-10 1/5/2004 16 SP-0009B ESFB 4.4E-08 3.1E-09 16 4.4E-08 3.1E-09 1/7/2004 4 SP-0010B SEQB 1.1E-08 7.8E-10 4 1.10E-08 7.8E-10 SDG 22 358 8.9E-07 6.6E-08 1/17/2004 3 SP-0005S SSPSS 1.0E-08 6.2E-10 3 2.7E-09 8.7E-11 1/17/2004 3 SP-0006S SSPSS 1.0E-08 6.2E-10 3 2.7E-09 8.7E-11 2/8/2004 3 SP-0007C ESFC 3.3E-08 2.0E-09 3 3.4E-09 1.5E-10 2/8/2004 3 SP-0008C ESFC 3.3E-08 2.0E-09 3 3.4E-09 1.5E-10 2/8/2004 4 SP-0010C SEQC 4.3E-08 2.6E-09 4 4.4E-09 2.00E-10 2/14/2004 16 SP-0009C ESFC 1.7E-07 1.1E-08 16 1.8E-08 8.0E-10 2/22/2004 3 SP-0008A ESFA 6.2E-08 1.5E-09 3 7.2aE-09 1.0E-10 2/22/2004 3 SP-0007A ESFA 6.2E-08 1.5E-09 3 7.2E-09 1.0E-10 2/22/2004 4 SP-0010A SEQA 8.2E-08 2.0E-09 4 9.3E-09 1.3E-10 2/28/2004 16 SP-0009A ESFA 3.3E-07 8.2E-09 16 3.8E-08 5.5E-10 2/29/2004 3 SP-0005R SSPSR 1.0E-08 6.2E-10 3 2.7E-09 8.7E-11 2/29/2004 3 SP-0006R SSPSR 1.0E-08 6.2E-10 3 2.7E-09 8.7E-11 SDG22 2118 5.2E-06 3.9E-07 NDG 1760 1.78E-07 1.26E-08 ICCDP ICLERP ICCDP ICLERP Total 6.2E-06 4.3E-07 1.2E-06 8.6E-08