ML20215G125
| ML20215G125 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 10/08/1986 |
| From: | Long S Office of Nuclear Reactor Regulation |
| To: | Harrison R PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| References | |
| NUDOCS 8610200046 | |
| Download: ML20215G125 (8) | |
Text
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g DCT E66 Docket Nos.: 50-443 and 50-444 Mr. Robert J. Harrison President & Chief Executive Officer Public Service Company of New Hampshire Post Office Box 330 Manchester, New Hampshire 03105
Dear Mr. Harrison:
Subject:
Request for Additional Information for Seabrook Station, Units 1 and 2, Emergency Planning Sensitivity Study The enclosed Request for Additional Information documents the oral and handwritten questions transmitted to Public Service Company of New Hampshire personnel and' contractors during our meeting in Bethesda, Maryland on September 23, 1986.
Please provide your responses promptly to facilitate our review.
Questions or additional information regarding this matter should be directed to the Technical Project Manager for the review of the Seabrook Emergency Planning Sensitivity Study, S. M. Long (301) 492-8413.
Sincerely, Steven M. Long, Project Manager PWR Project Directorate No. 5 Division of PWR Licensing-A
Enclosure:
As stated cc: See next page DISTRIBUTION
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, a was Docket Nos.: 50-443 and 50-444 Mr. Robert J. Harrison President & Chief Executive Officer Public Service Company of New Hampshire Post Office Box 330 Manchester, New Hampshire 03105
Dear Mr. Harrison:
Subject:
Request for Additional Information for Seabrook Station, Units 1 and 2, Emergency Planning Sensitivity Study The enclosed Request for Additional Information documents the oral and handwritten questions transmitted to Public Service Company of New Hampshire personnel and contractors during our meeting in Bethesda, Maryland on September 23, 1986.
Please provide your responses promptly to facilitate our review.
Questions or additional information regarding this matter should be directed to the Technical Project Manager for the review of the Seabrook Emergency Planning Sensitivity Study, S. M. Long (301) 492-8413.
Sincerely, Steven M. Long, Project Manager PWR Project Directorate No. 5 Division of PWR Licensing-A
Enclosure:
As stated cc: See next page t
Mr. Robert J. Harrison Public Service Company of New Hampshire Seabrook Nuclear Power Station cc:
Thomas Dignan, Esq.
E. Tupper Kinder, Esq.
John A. Ritscher, Esq.
G. Dana Bisbee, Esq.
Ropes and Gray Assistant Attorney Gen.eral 225 Franklin Street Office of Attorney General Boston, Massachusetts 02110 208 State Hosue Annex Concord, New Hampshire 03301 Mr. Bruce B. Beckley, Project Manager Public Service Company of New Hampshire Resident Inspector Post Office Box 330 Seabrook Nuclear Power Station Manchester, New Hampshire 03105 c/o US Nuclear Regulatory Commission Post Office Box 700 Dr. Mauray Tye, President Seabrook, New Hampshire 03874 Sun Valley Association 209 Summer Street Mr. John DeVincentis, ' Director Haverhill, Massachusetts 01839 Engineering and I.icensing Yankee Atomic Electric Company Robert A. Backus, Esq.
1671 Worchester Road O'Neil, Backus and Spielman Framingham, Massachusetts 01701 116 lowell Street Manchester, New Hampshire 03105 Mr. A. M. Ebner, Project Manager United Engineers & Constructors William S. Jordan, III 30 South 17th Street Diane Curran Post Office Box 8223 Harmon, Weiss & Jordan Philadelphia, Pennsylvania 19101 20001 S Street, NW Suite 430 Washington, D.C.
20009 Mr. Philip Ahrens, Esq.
Assistant Attorney General State House, Station #6 Augusta, Maine 04333 Carol S. Sneider, Esq.
Office of the Assistant Attorney General Environmental Protection Division Mr. Warren Hall One Ashburton Place Public Service Company of Boston, Massachusetts 02108 New Hampshire Post Office Box 330 D. Pierre G. Cameron, Jr., Eso.
Seabrook, New Hampshire 03874 General Counsel Public Service Company of New Hampshire Seacoast Anti Pollution f.eague Post Office Box 330 Hs. Jane Doughty Manchester, New Hampshire 03105 5 Market Street Portsmouth, New Hampshire 03801 Regional Administrator, Region I U.S. Nuclear Regulatory Commission Mr. Diana P. Randall 631 Park Avenue 70 Collins Street King of Prussia, Pennsylvania 19406 Seabrook, New Hampshire 03874 Richard Hampe, Esq.
New Hampshire Civil Defense Agency 107 Pleasant Street Concord, New Hampshire 03301
t Public Service Company of Seabrook Nuclear Power Station New Fampshire CC:
Mr. Calvin A. Canney, City Manager Mr. Alfred V. Sargent, City Hall Chairman 126 Daniel Street Board of Selectmen Portsmouth, New Hampshire 03801 Town of Salisbury, MA " 01950 Ms. Letty Hett Senator Gordon J. Humphrey Town of Brentwood ATTN: Tom Burack RFD Dalton Road U.S. Senate Brentwood, New Hampshire 03833 Washington, D.C.
20510 Ms. Roberta C. Pevear Mr. Owen B. Durgin, Chairman Town of Fampton Falls, New Hampshire Durham Board of Selectmen Drinkwater Road Town of Durham Hampton Falls, New Hampshire 03844 Durham, New Hampshire 03824 Ms. Sandra Gavutis Charles Cross, Esq.
Town of Kensington, New Hampshire Shaines, Mardrigan and RDF 1 McEaschern East Kingston, New Hampshire 03827 25 Maplewood Avenue Post Office Box 366 Portsmouth, New Hampshire 03801 Chairman, Board of Selectmen RFD 2 South Hampton, New Hampshire 03827 Mr. Guy Chichester, Chaiman Rye Nuclear Intervention Mr. Angie Machiros, Chairman Committee Board of Selectmen c/o Rye Town Hall for 'the Town of Newbury 10 Central Road Newbury, Massachusetts 01950 Rye, New Hampshire 03870 Ms. Cashman, Chairman Jane Spector Board of Selectmen Federal Energy Regulatory Town of Amesbury Commission Town Fall 825 North Capital Street, NE Amesbury, Massachusetts 01913 Room 8105 Washington, D. C.
20426 Ponorable Peter J. Matthews Mayor, City of Newburyport Mr. R. Sweeney Office of the Mayor New Hampshire Yankee Division City Hall Public Service of New Hampshire Newburyport, Massachusetts 01950 Company 7910 Woodmont Avenue Mr. Donald E. Chick, Town Manager Bethesda, Maryland 20814 Town of Exeter 10 Front Street Mr. William B. Derrickson Exeter, New Hampshire 03823 Senior Vice President l
Public Service Company of l
New Hampshire Post Office Box 700, Route 1 1
Seabrook, New Pampshire 03874 l
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s Enclosure REQUEST FOR ADDITIONAL INFORMATION SEABROOK STATION, UNITS 1 AND 2 DOCKET N05.:
50-443 AND 50-444 EMERGENCY PLANNING SENSITIVITY STUDY 1.
Describe how the overpressurization calculations made by SMA were checked or design reviewed.
2.
A meeting should be arranged with the originator of these calculations to assist the BNL reviewers in following these calculations and understanding the assumptions.
3.
Document the basis for the assumptions in the calculations.
In particular, explain the uncertainty factors assigned to various pressure capacities.
4.
Explain the mechanism for transferring the load from the penetration sleeves to the containment wall, in particular, the equipment hatch, when subjected to high strain conditions. Explain how the rebars around the penetrations were assessed to assure that they can resist these loads in addition to the primary pressure induced loads.
5.
The calculations use a rebar ultimate stain value of 4.7%, i.e., more than 21 feet of linear extension for the hoop bars. This linear extension under the high pressure load will be accommodated by formation of cracks in the concrete totaling approximately 21 feet in width. Justify the assumption that the pressure loads will be carried proportionately by the linear plate and the rebars (similar to the elastic condition) in this highly cracked condition. Also address the potential for developing a crack large enough for the local extension of the liner plate to lead to its failure at that point.
6.
Was compatibility of strains in the rebars and the liner plate satisfied in the calculations? For example, the outermost hoop bars will fail before the inside bars and the liner plate reach their respective ultimate strengths.
Was this fact reflected in the calculations? In addition, how is the biaxi_al stress-strain state of the liner plate considered.
7.
The combined tension, shear and bending effect at base and spring line levels was not considered in the calculations (Ref. p. 35, assumption 6).
Verify that the combined effect does not change the conclusions of the analysis.
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Since 31 cadwelds out of a total of 169 test samples failed at a stress lower than the rebar ultimate strength and there was apparently a construction problem concerning staggering of these welds, provide justification for not using a reduced ultimate strength for the rebar.
9.
The containment analysis is based on an axisymmetric geometry and loading.
This is not the case due to the presence of adjoining structures such as the fuel building and main steam and feedwater pipe chase.
Identify these axisymmetric conditions and assess their impact on the failure modes and analysis.
- 10. Only a sample of pipe penetrations are considered in some detail (X-23, X-26andX-71). The justification to consider only these should be provided.
- 11. A structural evaluation of electrical penetrations should be provided.
- 12. The basis for the leakage area assigned to the flued head at failure should be provided.
- 13. A more detailed evaluation of the impact of punching shear at the Fuel Transfer Building should be provided.
- 14. Clarify the extent to which double ended piping failures have been considered in the everall containment performance assessment.
Provide isometric drawings of all piping attached to containment penetrations.
15.
In PLG-0465, page 2-10, Figure 2-3, the conditional frequency of exceeding whole body dose vs distance appears to be driven by the S2 source term.
If this is the case, please describe all accident sequences (internal and external events) that contribute to the frequency of the S2 source term given in Table 4-2, pg. 4-7.
in particular, defir.e how the, timing and size of containment leakage was determined for each of these classes of accident sequences. Justify the appropriateness of the binning of'each of the accidents into this particular source term.
- 16. Provide justification for the liner yield stress increase from the specified yield stress of 32 ksi to a mean yield stress of 45.4 ksi.
17.
Indicate the correlation between containment failure sequences and the containment failure modes.
- 18. Provide the basis for concluding that the sight glasses in the hatches will not fail under high containment temperature and pressure conditions.
- 19. Document the effect that the recent update in seismic fragilities will have on the conclusions of the PSA results.
s 20. Assess the impact on risk of using the assumption of ultimate containment capability predicted by VE&C analysis (150 psig).
- 21. What is the impact on risk from accidents during shutdown and refueling when the containment function may not be available?
22.
It is the staffs understanding that preexisting violations of containment-integrity were " included" in the PSA by assuming the average effect was to raise the containment leak rate to the design basis value of 0.1%/ day, a.
Compare this assumption with the containment integrity violation data presented in NUREG/CR 4220.
b.
What contributions would these containment integrity violation data.
make to the probabilities for each of the release categories (Assume the S5W category is redistributed over all the appropriate categories by the conditional probabilities of preexisting leakage paths of the size appropriate to each category).
23.
a.
Provide a narrative description that quantitatively delineates the dominant contributors to the dose probability vs distance curves and the early fatality probability curves. The dominant release categories should be specified and the dominant accident' sequences contributing to each of these release categories should be specified.
The probability of occurrence of each release category should be stated. These data should be provided for the current study and for the original PSA results. Changes between the two studies should be attributed to specific differences in the analysis.
b.
Provide a set of early fatality conditional probability curves for each release category, assuming evacuation distances of 1 mile and 2 miles, c.
Provide the conditional mean risk of early fatality for each of the curves provided in b.
- 24. Provide a quantitative description of the effects of the following differences between the original PSA and the current study:
a.
reduction in probability of core-melt V sequences b.
factor of 1000 scrubbing of releases through RHR seals c.
changeofreleasecategory(S6toSI)forunscrubbedeventVsequences.
The effects should be described in terms of differences in risk curves for early fatalities and for 200 rem vs distance.
- 25. Provide a list of all paths for loss of RCS inventory outside containment.
Show how these have been considered with respect to LOCA and with respect to containment bypass for radioactive materials following core damage.
s 26.
Indicate the extent to which the effect of local deflagration / detonation of hydrogen qas concentration in localized areas both inside and outside the containment has been considered in the assessment of risk.
Include a discussion of how weak areas of containment have been considered in your assessment, for example, the containment is considerably weaker in its resistance to pressure loading from outside the containment.
28.
Identify any penetrations connected directly into the containment atmosphere which rely on any remote manual or manual valves for isolation.
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