ML17164B025
| ML17164B025 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 04/27/1999 |
| From: | Nerses V NRC (Affiliation Not Assigned) |
| To: | Byram R PENNSYLVANIA POWER & LIGHT CO. |
| Shared Package | |
| ML17164B026 | List: |
| References | |
| REF-GTECI-A-45, REF-GTECI-DC, TASK-A-45, TASK-OR GL-88-20, TAC-M83683, TAC-M83684, NUDOCS 9905040052 | |
| Download: ML17164B025 (10) | |
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. UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 April 27, 1999 Mr. Robert G. Byram Senior Vice President-Generation and Chief Nuclear Officer PP8L, Inc.
2 North Ninth Street Allentown, PA 18101
SUBJECT:
SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1 AND 2 - INDIVIDUAL PLANT EXAMINATIONOF EXTERNALEVENTS (IPEEE) SUBMITIAL
(TAC NOS. M83683 AND M83684)
Dear Mr. Byram:
Enclosed is the Staff Evaluation Report (SER), which documents the staff's finding and conclusions, of its review of the Susquehanna Steam Electric Station (SSES) IPEEE submittal.
Also included with the SER is the contractor's (Energy Research, Inc.) Technical Evaluation Report (TER) and supplemental TER.
A "Step 1" review was performed which examined the IPEEE results for their completeness and "reasonableness" considering the design and operation of Susquehanna.
On the basis of this review and further review by a senior review board (SRB), the staff concluded that the aspects of high winds, floods, and transportation and other external events were adequately addressed.
However, the seismic and fire IPEEEs needed a more detailed, "Step 2," review because of specific concerns related to seismic and fire analyses (e.g., seismic capacity calculations, outlier resolutions, unusually low fire core damage frequency (CDF) results, compartment screening criterion used in the analysis, and human error analysis).
For a detailed discussion of these concerns, see Section 3 of the attached TER. The SRB is comprised of Nuclear Regulatory Research (RES) and Nuclear Reactor Regulation (NRR) staff and RES consultants (Sandia National Laboratories) with probabilistic risk assessment expertise for external events.
The Nuclear Regulatory Commission (NRC) provided a site audit plan for t)e "Step 2" review to your staff in March 1998, to facilitate PP8 L, Inc.'s preparation for the NRC site audit. The audit plan focused on those seismic and fire concerns identified during the Step 1.review. The site audit was held on August 4-5, 1998, and included technical discussions with your staff, review of your staff's technical analyses and documentation held at the site, and walkdowns of the plant. Your staff responded to all seismic and fire issues identified in the audit plan by means of verbal responses during the site audit, as well as by means of interactive seismic and fire walkdowns.
In addition, by letter dated October 15, 1998, you submitted additional information that had been verbally requested during the audit. Energy Research Inc.
completed the supplement to its TER in December 1998. Our review findings are summarized in the enclosed SER, and the details of the contractor's findings are presented in the TER and its supplement which appear in attachments to the SER.
9905040052 990427 PDR ADOCK 05000387 P
I PP8 L, Inc. (licensee) estimated the plant seismic capacity, in terms of high confidence of low probability of failure (HCLPF) value, to be 0.21g due to a low seismic capacity of certain components.
However, PP&L, Inc. stated that these low-capacity components are not strictly required for either safe shutdown of the plant, or their failures may be rectified through manual recovery actions, and the licensee concluded that the plant HCLPF capacity meets the 0.3g review level earthquake (RLE).
PP8L, Inc. originally estimated a total fire CDF of 1E-9 per refueling cycle (12-18 months),
which is significantly smaller than CDF values reported by other comparable studies of similar plants.
PP&L, Inc. later performed a sensitivity analysis on CDF from fires in the upper cable spreading rooms, one of the significant scenarios, which showed the resulting CDF in this area to be 2.4E-7 per reactor year (RY), three orders of greater magnitude than the CDF originally reported for this area.
Although PP8 L, Inc. did not perform additional sensitivity analyses to revise the results for all other scenarios, similar results could be anticipated for those scenarios; this may be an indication that the fire CDF estimate at Susquehanna could be three orders of magnitude higher than the originally reported CDF. PP&L, Inc. estimated that the CDF due to internal events is about 5E-7/RY.
Based on Susquehanna's conformance to the 1975 Standard Review Plan, PP8,L, Inc.
considered other external events (e.g., external floods and high winds) to be insignificant contributors to severe accidents at the Susquehanna site.
I PP8L, Inc. did not provide a definition of a severe accident vulnerability and did not identify any yulnerabilities associated with external events. 'However, minor plant improvements and procedural changes resulting from the seismic and fire IPEEE analyses were implemented at the Susquehanna plant site.
PP8L, Inc. has addressed generic safety issues (GSls) GSI-57, "Effects of Fire Protection System Actuation on Safety-Related Equipment," GSI-103, "Design for Probable Maximum Precipitation (PMP)," Unresolved Safety Issue (USI) A-45, "Shutdown Decay Heat Removal Requirements," and the Fire Risk Scoping Study (FRSS) issues which were explicitly requested in Supplement 4 to GL 88-20 and its associated guidance in NUREG-1407.
On the basis of the "Step 1" and "Step 2" reviews, the staff concludes that PP8,L, Inc.'s IPEEE process is capable of identifying the most likely severe accidents and severe accident'ulnerabilities and, therefore, that the Susquehanna IPEEE has met the intent of Supplement 4 to Generic Letter 88-20.
In addition, PP&L, Inc.'s IPEEE submittal contains some specific information that addresses the external event aspects of certain generic safety issues (GSI-147, "Fire-Induced Alternate Shutdown/Control Room Panel Interactions," GSI-148, "Smoke Control and Manual Fire-Fighting Effectiveness," and GSI-172, "MultipleSystem Responses Program (MSRP))." The specific information associated with each issue is identified and discussed in the attached SER.
Based on the review of the information contained in the submittal, the staff considered that PP8L, Inc.'s process is capable of identifying potential vulnerabilities associated with these issues.
On the basis that no potential vulnerabilities associated with the external event
27, 1999
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aspects of these issues were identified at Susquehanna, the staff considers these issues resolved for Susquehanna.
Ifyou have any questions regarding the enclosed SER, please contact Victor Nerses, Senior PM, (301) 415-1484.
Sincerely, Original signed by:
Docket Nos. 50-387 and 50-388
Enclosure:
Staff Evaluation Report cc w/encl: See next page DISTRIBUTION:
g3ocket.Fil~e" PUBLIC PDI-1 R/F J. Zwolinski/S. Black S. Bajwa M. O'rien V. Nerses R. Norsworthy (e-mail SE)
OGC ACRS A. Blough, RGN-I T. King, RES A. Ruben, RES J. Chen, RES DOCUMENT NAME: G:iSUSQiGEN83683.WPD Victor Nerses, Senior Project Manager, Section 1
Project Directorate I
Division of Licensing Project Management Office of Nuclear Reactor Regulation To receive a copy of this document, indicate in the box: "C" = Copy without attachment/enclosure "E" = Copy with attachment/enclosure "N"= No co 0/VA~
. Mff OFFICE NAME DATE PDI-1 V er s Ice 04g799 P Dl-1/LAg/
DST/PRAB MO'Brien'Edtd 3/31/99 04/y7 9 OFFICIAL'ECORD COPY PDI-1/SC SBa'wa 04/
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(J 27, 1999 aspects of these issues were identified at Susquehanna, the staff considers these issues resolved for Susquehanna.
Ifyou have any questions regarding the enclosed SER, please contact Victor Nerses, Senior PM, (301) 415-1484.
Sincerely, Origina1 signed by:
Docket Nos. 50-387 and 50-388
Enclosure:
Staff Evaluation Report cc w/encl: See next page DISTRIBUTION:
Docket File PUBLIC PDI-1 R/F J. Zwolinski/S. Black S. Bajwa M. O'rien V. Nerses R. Norsworthy (e-mail SE)
OGC ACRS A. Blough, RGN-I T. King, RES A. Ruben, RES J. Chen, RES DOCUMENT NAME: G:iSUSQiGEN83683.WPD Victor Nerses, Senior Project Manager, Section 1
Project Directorate I
Division of Licensing Project Management Office of Nuclear Reactor Regulation To receive a copy of this document, indicate in the box: "C" = Copy without attachment/enclosure "E" = Copy with attachment/enclosure "N" = No co i.'PIA'- q'--.~ ~l"-/i
'i'FFICE PDI-1 PDI-1/LAj/,"/~2~
DST/PRAB PDI-1/SC NAME er s.lcc MO'Brien'...',".',
-'Edtd SBa'wa DATE 04g 799 3/31/99 04/g/99 OFFICIALRECORD COPY 04/
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aspects of these issues were identified at Susquehanna, the staff considers these issues resolved for Susquehanna.
Ifyou have any questions regarding the enclosed SER, please contact Victor Nerses, Senior PM, (301) 415-1484.
Sincerely, Victor Nerses, Senior Project Manager, Section 1
Project Directorate I
Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-387 and 50-388 I
Enclosure:
Staff Evaluation Report ccw/encl: See next page
Susquehanna Steam Electric Station, Units 1 &2 Bryan A. Snapp, Esq.
Assoc. General Counsel PP&L, Inc.
2 North Ninth Street, GENTW3 Allentown, PA 18101-1179 Terry L. Harpster Manager - Nuclear Licensing PP&L, Inc.
2 North Ninth Street, GENA61 Allentown, PA 18101-1179 Senior Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 35, NUCSA4 Berwick, PA 18603-0035 Director-Bureau of Radiation Protection Pennsylvania Department of Environmental Protection P.O. Box 8469 Harrisburg, PA 17105-8469 Richard W. Osborne
. Allegheny Electric Cooperative, Inc.
212 Locust Street P.O. Box 1266 Harrisburg, PA 17108-1266 Regional Adrriinistrator, Region I
U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Robert F. Saunders Vice President-Nuclear Site Operations Susquehanna Steam Electric Station Box 467, NUCSA4 Berwick, PA 18603-0035 Mr. Herbert D. Woodeshick Special Office of the President PP&L, Inc.
Rural Route 1, Box 1797 Berwick, PA 18603-0035 George T. Jones Vice President-Nuclear Engineering & Support PP&L, Inc.
2 North Ninth Street, GENA61 Allentown, PA 18101-1179 Dr. Judith Johnsrud National Energy Committee Sierra Club 433 Orlando Avenue State College, PA 16803 Board of Supervisors Salem Township P.O. Box 405 Berwick, PA 18603-0035
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