ML032461348

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Summary of Meeting with South Texas Project Nuclear Operating Company, Regarding Staff Review Issues with the Proposed Risk-Informed Inservice Testing Program
ML032461348
Person / Time
Site: South Texas  STP Nuclear Operating Company icon.png
Issue date: 09/02/2003
From: Gramm R
NRC/NRR/DLPM/LPD4
To:
Jaffe D, NRR/DLPM, 415-1439
References
TAC MB8948, TAC MB8949
Download: ML032461348 (11)


Text

September 2, 2003 LICENSEE: STP Nuclear Operating Company FACILITY: South Texas Project, Unit 1and Unit 2

SUBJECT:

SUMMARY

OF HEADQUARTERS AND SOUTH TEXAS PROJECT NUCLEAR OPERATING COMPANY TELEPHONE CONFERENCE CALL OF JULY 2, 2003, REGARDING STAFF REVIEW ISSUES WITH THE SOUTH TEXAS PROJECT PROPOSED RISK-INFORMED INSERVICE TESTING PROGRAM (TAC NOS. MB8948 AND MB8949)

On July 2, 2003, the U. S. Nuclear Regulatory Commission (NRC) Headquarters staff held a telephone conference call with STP Nuclear Operating Company (STPNOC), the licensee for South Texas Project (STP), Units 1 and 2. The purpose of the telephone conference call was to discuss the proposed Risk-Informed Inservice Testing (RI-IST) program submittal. The staff had previously transmitted 6 technical issues concerning the RI-IST submittal to STP on May 29, 2003 (ADAMS ML031490352). To support the July 2, 2003, discussions STP had provided the staff with some brief responses to the NRCs technical issues along with a matrix depicting the relationship of the proposed RI-IST change with respect to the previously approved special treatment exemption (Enclosure 1). A list of participants is enclosed as Enclosure 2.

During the call, STP provided clarifying and amplifying information about their proposed RI-IST program in response to the staffs concerns.

STP agreed that they could have done a better job documenting why their proposed RI-IST ranking for components differed from the special treatment exemption ranking. STP said they felt they could document the basis for these differences to the staffs satisfaction. The staff suggested that STP not start this substantive effort until after the staff makes a decision on the proposed RI-IST categorization approach.

The telephone conference call ended with STP and NRC staff indicating that they understood each others positions on the issues and that the NRC staff would discuss the viability of the STP proposed categorization approach with NRR management. The staff agreed to get back to STP on their proposed categorization approach as soon as practical. The STP personnel

also indicated they would further consider the NRC comments with respect to their proposed RI-IST methodology. Both parties agreed to have a follow-up discussion after the requisite internal interactions have been held.

/RA/

Robert A. Gramm, Chief, Section 1 Project Directorate IV Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499

Enclosures:

1. STP bullet responses to fundamental review issues with matrix
2. List of Participants cc w/encls: See next page

ML032461348 NRC-001 OFFICE PDIV-1/SECY PDIV-1/SC PDIV NAME DBaxley RGramm HBerkow DATE 9 / 02 /2003 9 / 02 /2003 9 / 02 /2003 South Texas Project, Unit 1 and Unit 2 cc:

Mr. Cornelius F. OKeefe Senior Resident Inspector A. H. Gutterman, Esq.

U.S. Nuclear Regulatory Commission Morgan, Lewis & Bockius P. O. Box 910 1111 Pennsylvania Avenue, NW Bay City, TX 77414 Washington, DC 20004 A. Ramirez/C. M. Canady Mr. T. J. Jordan, Vice President City of Austin Engineering & Technical Services Electric Utility Department STP Nuclear Operating Company 721 Barton Springs Road P. O. Box 289 Austin, TX 78704 Wadsworth, TX 77483 Mr. L. K. Blaylock S. M. Head, Manager, Licensing Mr. W. C. Gunst Nuclear Quality & Licensing Department City Public Service Board STP Nuclear Operating Company P. O. Box 1771 P. O. Box 289, Mail Code: N5014 San Antonio, TX 78296 Wadsworth, TX 77483 Mr. C. A. Johnson/A. C. Bakken Environmental and Natural Resources AEP Texas Central Company Policy Director P. O. Box 289 P. O. Box 12428 Mail Code: N5022 Austin, TX 78711-3189 Wadsworth, TX 77483 Jon C. Wood INPO Matthews & Branscomb Records Center 112 East Pecan, Suite 1100 700 Galleria Parkway San Antonio, TX 78205 Atlanta, GA 30339-3064 Arthur C. Tate, Director Regional Administrator, Region IV Division of Compliance & Inspection U. S. Nuclear Regulatory Commission Bureau of Radiation Control 611 Ryan Plaza Drive, Suite 400 Texas Department of Health Arlington, TX 76011 1100 West 49th Street Austin, TX 78756 D. G. Tees/R. L. Balcom Texas Genco, LP Brian Almon P. O. Box 1700 Public Utility Commission Houston, TX 77251 William B. Travis Building P. O. Box 13326 Judge, Matagorda County 1701 North Congress Avenue Matagorda County Courthouse Austin, TX 78701-3326 1700 Seventh Street Bay City, TX 77414 May 2003

South Texas Project, Unit 1 and Unit 2 cc:

Susan M. Jablonski Office of Permitting, Remediation and Registration Texas Commission on Environmental Quality MC-122 P.O. Box 13087 Austin, TX 78711-3087 Mr. Terry Parks, Chief Inspector Texas Department of Licensing and Regulation Boiler Division P. O. Box 12157 Austin, TX 78711 Mr. Ted Enos 4200 South Hulen Suite 630 Ft. Worth, Texas 76109 Mr. James J. Sheppard President and Chief Executive Officer STP Nuclear Operating Company South Texas Project Electric Generating Station P. O. Box 289 Wadsworth, TX 77483 May 2003

NRC Staffs Issues with STPNOCs Proposed RI-IST Program STP has reviewed the NRC staff feedback on the subject submittal, and believes that additional clarification is needed on each of the identified issues as stated below:

Issue 1 - RI-IST will recategorize SSCs

 RI-IST does not recategorize SSCs - SSCs remain categorized as per the STP Exemption

 RI-IST does not affect program scope - RI-IST merely identifies appropriate treatment strategies for scoped SSCs

 Reg Guides 1.174 and 1.175, as well as OMN-3 guidance, were followed to determine the appropriate treatment strategies Issue 2 - Proposed RI-IST and the STP Exemption impacts must be considered together

 The STP Exemption and the proposed RI-IST are separate issues - the Exemption determined the scope of SSCs in the IST Program, while RI-IST determines the treatment strategy for those SSCs remaining in the IST scope

 The sensitivity studies used to demonstrate the acceptability of the STP Exemption approach remain bounding for the proposed RI-IST Issue 3 - Proposed RI-IST does not properly address passive functions

 Certain SSCs are categorized as HIGH/MEDIUM due to pressure boundary considerations only - these SSCs do not require pressure boundary testing under either IST or proposed RI-IST

 In the PRA, passive refers to an SSC performing its function without changing state

 SSC repositioning after an event is an active function - the PRA specifically models off-normal states and the recovery actions as applicable

 RI-IST will test all safety functions as required by the Code Issue 4 - RI-IST will not properly test scoped components

 Per the approved STP Exemption, SSCs categorized as LOW/NRS are removed from the scope of IST - LOW/NRS SSCs are not within the scope of the RI-IST request

 RI-IST merely applies treatment strategies for scoped SSCs consistent with RG1.175

 Per RG1.175, staggered testing of valve groups is permitted - test interval is no greater than the number of valves in a group x 18 months - we will not exceed a test interval of 6 years

 The STP proposal is consistent with RI-IST programs already approved for Comanche Peak and San Onofre ENCLOSURE 1

Issue 5 - HSS/MSS SSCs must be evaluated for enhanced treatment

 Per the STP Exemption, Box 2 SSCs must be evaluated for enhanced treatment

- there are no Box 2 SSCs in the existing IST Program or in the proposed RI-IST Program

 During the categorization process (which is not part of this RI-IST request), Box 1 SSCs are evaluated for enhanced treatment only if beyond design basis functions are identified

 STP has chosen to add certain safety significant SSCs into the RI-IST program which are not scoped in the existing IST Program - these new SSCs will be trended as part of their treatment Issue 6 - Common cause is not properly addressed in the proposed RI-IST

 STPs approach to common cause is extremely conservative - if we were to apply a common cause approach similar to already-approved RI-IST programs, a significant number of STPs SSCs would migrate from a more robust treatment approach to a more relaxed treatment approach

 ASME PRA standard (DG-1122) does not require modeling of inter-system common cause

 STPs cultural approach to potential common cause issues is both a strength and is conservative, as highlighted by the recent MOV issue - following 100%

inspection by STP, only the initial identified deficiency could have affected component functionality

Risk-Informed Inservice Testing Program Matrix RISC-1 RISC-2 Safety Related Non-Safety Related High Safety Significant High Safety Significant RISC-3 RISC-4 Safety Related Non-Safety Related Low Safety Significant Low Safety Significant IST TREATMENT HIGH MEDIUM LOW SSC Not Exempt SSC Not Exempt SSC Not Exempt IST Code Test IST Extended Interval IST Extended Interval Enhanced Testing with Compensatory Measure with Performance Monitoring HIGH 13 Valve Groups - 40 Valves 8 Valves Groups - 31 Valves 4 Valve Groups - 13 Valves 4 Pump Groups - 10 Pumps 4 Pump Groups - 12 Pumps 0 Pumps - 0 Pumps

  • 1 Valve Group - 3 Valves *1 Valve Group - 3 Valves
  • 2 Valve Groups - 6 Valves SSC Not Exempt SSC Not Exempt SSC Not Exempt IST Code Test IST Extended Interval IST Extended Interval Enhanced Testing with Compensatory Measure with Performance Monitoring MEDIUM 0 Valve Groups - 0 Valves 11 Valve Groups - 39 Valves 39 Valve Groups - 131 Valves 0 Pump Groups - 0 Pumps 1 Pump Group - 2 Pumps 1 Pump Group - 2 Pumps EXEMPTION CATEGORIZATION SSC Exempt SSC Exempt SSC Exempt IST Code Test IST Extended Interval IST Extended Interval Enhanced Testing with Compensatory Measure with Performance Monitoring LOW 0 Valve Groups - 0 Valves 0 Valve Groups - 0 Valves 92 Valve Groups - 186 Valves 0 Pump Groups - 0 Pumps 0 Pump Groups - 0 Pumps 3 Pump Groups - 8 Pumps SSC Exempt SSC Exempt SSC Exempt IST Code Test IST Extended Interval IST Extended Interval Enhanced Testing with Compensatory Measure with Performance Monitoring NRS 0 Valve Groups - 0 Valves 0 Valve Groups - 0 Valves 20 Valve Groups - 57 Valves 0 Pump Groups - 0 Pumps 0 Pump Groups - 0 Pumps 0 Pump Groups - 0 Pumps
  • Valve group has different ranks for the open and close functions

TREATMENT COMPARISONS Commache Peak IST SONGS IST STP IST HIGH 138 SSCs - 20.7% 114 SSCs - 15.8% 53 SSCs - 9.9%

MEDIUM N/A 64 SSCs - 7% 87 SSCs - 16.2%

LOW 529 SSCs - 79.3% 693 SSCs - 76.1% 397 SSCs - 73.9%

STP EXEMPTION RANKS STP IST w/Code Thresholds HIGH 112 SSCs - 20.9% 17 SSCs - 3.2%

MEDIUM 174 SSCs - 32.4% 35 SSCs - 6.5%

LOW 194 SSCs - 36.1% 485 SSCs - 90.3%

NRS 57 SSCs - 10.6%

LIST OF PARTICIPANTS STP/NRC TELEPHONE CONFERENCE CALL JULY 2, 2003 Licensees Participants S. Head G. Schinzel W. Stilwell P. Walker B. Scott NRC Participants D. Harrison D. Fischer M. Thadani D. Terao H. Berkow M. Tschiltz ENCLOSURE 2