ML20101S487
| ML20101S487 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 02/01/1985 |
| From: | Devincentis J PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| To: | Knighton G Office of Nuclear Reactor Regulation |
| References | |
| SBN-756, NUDOCS 8502050435 | |
| Download: ML20101S487 (4) | |
Text
r SEABROOK STATION
_e)(y Engineering Office
~d neae s.,*. or new Hampv*.
February 1, 1985 New Hampshlee Yonkee Olvlelen SBN - 756 T.F.
B7.1.2 United States Nuclear Regulatory Commission Washington, D. C. 20555 Attention:
Mr. George W. Knighton, Chief Licensing Branch No. 3 Division of Licensing
References:
(a) Construction Permits CPPR-135 and CPPR-136, Docket Nos. 50-443 and 50-444 (b) PSNil Letter SBN-703, dated August 9, 1984, " Alternate Pipe Break Design Criteria", J. DeVincentis to C. W. Knighton (c) Generic Letter 84-04, dated February 1, 1984, " Safety Evaluation of Westinghouse Topical Reports Dealing With Elimination of Postulated Pipe Breaks in PWR Primary Main Loops", from D. C. Eisenhut (d) NUREG-1061, Volume 3, " Report of the US Nuclear Regulatory Commission Piping Review Committee", published November 1984
Subject:
Reactor Coolant Loop Pipe Break Elimination Benefits Summary
Dear Sir:
We previously requested [ Reference (b)] that the NRC " approve the elimination of postulated breaks in the Reactor Coolant Loop (RCL) primary piping of Seabrook Station Units 1 and 2".
We also indicated that NRC
" acceptance of our request for elimination of RCL primary pipe breaks would result in significant benefits in terms of reduced occupational radiation exposure and cost savings over the life of the units".
Attachment A to this letter, which was prepared pursuant to the guidance set forth in Reference (c), quantifies the benefits that will result from the granting of our request for partial exemption from General Design Criteria 4 (GDC 4) of 10CFR50 Appendix A.
The granting of this partial exemption from CDC 4 will eliminate the need to postulate longitudinal and circumferential pipe breaks in the RCL primary piping (hot leg, cold leg, and crossover leg piping). This will eliminate the need to install associated pipe whip restraints in the RCL primary piping and eliminate the requirement to analyze and design for the dynamic effects of these breaks including jet impingement, reactor cavity pressurization and load combination assumptions.
8502050435 850201 PDR ADOCK 05000443 A
PDR OI P.O Box 300. Seabrook,NH03874
- Telephone (603)474 9521 8 i L_
e--
O Mr. George W. Knighton, Chief SBN-756 Page 2 PSNH's evaluation of the potential cost savings and operational benefits is provided in Attachment A.
These benefits include an approximate
$6.1 million savings associated with the design, fabrication, and installation of hardware, and the man-rem cost of associated maintenance and handling. The corresponding occupational radiation exposure reduction is anticipated to be 1,380 man-rems. This benefits evaluation was performed for both units over their 40 year life. The actual benefits realized are expected to be higher than those presented, due to the conservative nature of our assumptions and other expected future attributes.
In summary, we have demonstrated that our request for partial exemption from CDC 4, if granted, will result in significant cost savings, occupational radiation exposure reduction, and other operational benefits over the life of the units. Your approval of this request would be consistent with the following conclusion, which the NRC Pipe Break Task Group reported in NUREG-1061, Volume 3 [ Reference (d)]:
"The elimination of the DEGB at terminal ends of large primary pipes in pressurized water reactors (PWRs), and the control of maximum flaw length in piping in general should permit an elimination of existing restraints or removal of restraints as a design requirement.
Consequently, asymmetric reactor pressure vessel (RPV) loads, jet impingement loads, and reactor cavity over pressurization that results from a postulated DEGB need not be considered."
(p. ES-2)
Please note that construction and engineering decisions are being dictated by the expected approval of our request for partial exemption from GDC 4; therefore, we would hope that any concerns or additional information needs would be brought to our attention expeditiously.
Very truly y urs,
/
J. DeVincentis, Director Engineering and Licensing Attachment cet Atomic Safety and Licensing Board Service List
F 1'1111ma S. J;rdan, III l
Ciane Curran
(
Harmon, Weica & J rdan i
20001 S Street N.W.
Brentwood Board of Selectmen Suite 430 RED Dalton Road Washington, D.C.
20009 Brentwood, New Hampshire 03833 Robert G. Perlis Office of the Executive Legal Director Edward F. Meany U.S. Nuclear Regulatory Commission Designated Representative of Washington, DC 20$$$
the Town of Rye 155 Washington Road Robert A. Backus Esquire Rye, NH 03870 116 Lowell Street P.O. Box 516 Calvin A. Canney Mancehster, NH 03105 City Manager City Hall Philip Ahrens, Esquire 126 Daniel Street Assistant Attorney General Portsmouth, NH 03801 Department of the Attorney Ceneral Augusta, ME 04333 Dana Bisbee, Esquire Assistant Attorney General Mr. John B. Tanzer Office of the Attorney General Designated Representative of 208 State House Annex the Town of Hampton Concord, NH 03301 5 Morningside Drive Hampton, NH 03842 Anne Verge, Chair. arson Board of Selectmen Roberta C. Pevear Town Hall Designated Representative of South Hampton, NH 03S42 the Town of Hampton Falls Drinkwater Road Patrick J. McKeon Hampton Falls, NH 03844 Selectmen's Office 10 Central Road Mrs. Sandra Cavutis Rye, NH 03670 Designated Representative of the Town of Kensington Carole T. Kagan, Esq.
RFD 1 Atomic Safety and Licensing Board Panel East Kingston, NH 03827 U.S. Nuclear Regulatory Commission Jo Ann Shotwell, Esquire Assistant Attorney General Mr. Angie Machiros Environmental Protection Bureau Chairman of the Board of Selectmen Department of the Attorney General Town of Newbury One Ashburton Place, 19th Floor Newbury, MA 01950 Boston, MA 02108 Town Manager's Of fice Senator Cordon J. Humphrey Town Hall - Friend Street U.S. Senate Amesbury, Ma.
01913 Washington, DC 20510 (Attn Tom Burack)
Senator Cordon J. Humphrey 1 Pillsbury Street Diana P. Randall Concord, NH 03301 70 Collins Street (Attn: Herb Boynton)
SE4 brook, NH 03874 Richard E. Sullivan, Mayor Donald E. Chick City Hall Town Manager Newburyport, FM 01950 Town of Exeter 10 Tront Street Exeter, NH 03833
-s SBN-756
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ATTACHNENT A
' Estimated Cost Savinas/ Operational Benefit Summary i
,^
for Elimination of RCL Primary Pipe Breaks l
\\
I-Category
- Cost Savings (1985 rates)
Operational Benefits 1.
Elimination of RCL' PWR Installation (to Substantial improvement Pipe Whip Restraints complete Unit 2) - $520K in quality of ISI
^(PWR)
PWR hot shimming - $125K Eliminates need to maintain gap clearances and the potential for inadvertent thermal movement restriction i
Reduces RCL heat loss
.l to containment
- Man-rem cost - $300K Estimated personnel dose reduction (100 man-ress) 1 2.
Elimination of neutron EAR pad design, fabrication, Reduced congestion in shield energy and installation - $210K reactor cavity-absorption (EAB) pads EAR pad removal and reinstallation during each refueling - $100K
- Non-rem cost - $3.85N Estimated personnel dose reduction (1,280 man-ress) 3.
Elimination of jet Jet shield design, Reduced congestion shields and/or fabrication, and resulting in personnel equipment. relocation installation - $1.ON dose. reduction TOTALL B6.105 Million 1,380 man-rees Both units unless'noted'otherwise. Note that the Unit 2 status is indeterminate.-
Anticipated radiation worker charges based on typical $/ man-rea billed *by
. industry..
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