ML18031A118
| ML18031A118 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 02/26/1979 |
| From: | Parr O Office of Nuclear Reactor Regulation |
| To: | Curtis N PENNSYLVANIA POWER & LIGHT CO. |
| References | |
| NUDOCS 7903190355 | |
| Download: ML18031A118 (6) | |
Text
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'Distributio Doc et F) e NRC PDR Local,PDR LWR 83 File R.
Boyd D: Vassallo Docket ffos. 50-387 a
-388 osure:
F. Wll iams
- 0. Parr S. Niner N. Rushbrook R. Nattson D;-. Ro"ss J. 'Knight R. Tedesco
=-R.
DeYoung V. ftoore
, R. Vollmer N. Ernst R. Denise R.
Hartfield'ELD IE (3)
B. W.,Sheron L. E. Philips FEB a6 t979 tlr. Horpen W. Curtis
'ice President - Engineering and Construction Pennsylvania Power and Light Company 2 North Ninth Street,-
Allentown,'ennsylvania 18101
Dear Nr. Curtis:
SUBJECT:
SUSflUE)IANNA STEAf1 ELECTRIC STATION UNIT ffOS.
1 AND '2-I BCC:
JBuchanan TAbernathy ACRS (16)
RE(VEST FOR ADDITIONAL INFORMATION As a result of,our review of your application for operating licenses for the Susquehanna Steam Electric Plant, we, find that we need additional information in the area of Re~ctor Analysis.
The specific information-required is listed in the Enclosure.
Please inform us of the date when this requested additional information will be available for our review.
Pl.ease contact us if you desire any discussion or clarification of the information requested.
Sincerely, Orlglnal Sly~ by 0- KL Porc Olan D. Parr, Chief Light Water'Reactors Branch Ho.
3 Division of Project Management
Enclosure:
As Stated cc w/enclosure:
, See next page
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Mr. Norman W. Curtis FEB P6 1979 cc:
Mr. Earle M. Mead Project Engineering Manager Pennsylvania Power
& Light Company 2 North Ninth Street.
Allentown, Pennsylvania 18101 Jay Silberg, Esq.
Shaw, Pittman, Potts Trowbridge 1800 H Street, N.
W.
Washington, D. C.
20036 Hr. William E. Barberich, Nuclear Licensing Group Supervisor Pennsylvania Power
& Light Company 2 North Ninth Street Allentown, Pennsylvania 18101 Edward M. Nagel, Esquire General Counsel and Secretary Pennsylvania Power
& Light Company 2 North Ninth Street11entown, Pennsylvania 18101 Bryan Snapp, Esq.
Pennsylvania Power
& Light Company 901 Hamilton Street Allentown, Pennsylvania 18101 Robert M. Gallo Resident Inspector P. 0.
Box 52 Shickshinny, Pennsylvania 18655 Mr. Robert J.
Shovl in Project Manager Pennsylvania Power and Light Co.
2 North Ninth Street Allentown, Pennsylvania 18101 Alan R. Yuspeh, Esq.
Shaw, Pittman, Potts Trowbridge 1800 H Street, N.
W.
Washington, D. C.
20036
221. 0 221.2 (None) 221 i:3 (4.4.2.2.1) 221. 4 (4.4. 2. 5) 221. 5 (4.4.2.5, Table 4.4-6)
AAALYSIS BRANCH - ANALYSIS SECTION Section 4.4 contains no discussion of crud and its effect on CPR and core pressure drop.
Provide the assumptions used for amount of crud in design calculations and the sensitivity of CPR and core pressure drop to variations in the amount of crud present.
Also provide data supporting the assumption on crud thickness and discuss how crud build-up in the core would be detected.
The GEXL data base (for the approved correlation) is for 7x7 and 8x8 one water rod bundles.
No substantial data base has been provided to support the 8x8, two water rod design.
The GEXL correlation must be demonstrated to be applicable to the new 8x8 design, by comparison to appli-cable data, prior to issuance of an operating license for Susquehanna.
Alternatively, the HCPR limit may be increased by 0.05 to accommodate GEXL uncertainties.
You state on page 4.4-6 that "There is reasonable assurance, therefore, that the calculated flow distribution throughout the core is in close agreement with the actual flow distri-bution of an operating reactor."
Does this refer specifically to Susquehanna calculations?
What operating reactor was used for the data comparison?
Your flow distribution discussion does not address uncertainties on the flow distribution or the effect of channel flow uncertainty, coupled with other uncertainties on the HCPR. uncertainty.
- Also, Table 4.4-6 does not address flow distribution uncertainties.
Provide this information.
221.6 (4.4.4.5) 221.7 Page 4.4-17 states "Analytical models of the individual flow paths were developed as an independent check of the tests.
When using these models for hydraulic design calculations, nominal drawing dimensions are used."
Provide the assumptions and equations comprising the model and a comparison of model predictions with data.
What fraction of the fuel bundle flow is "water rod flow"?
221. 8 (4.4.4.5) 221. 9 (4.4.4.5) 221.10 (4.4.4.6.6, Figure 4.4-6)
Page 4.4-18 of the FSAR states that "the nominal expected bypass flow fraction is approximately 10 percent."
What is the calculated bypass flo>> fraction for Susquehanna and what is its uncertainty?
What is the name of the computer program cited in this section 4.4 4.5?
Provide references which document the code.
You state that the stability analyses performed in Section 4.4.4.6.6 and for Figure 4.4-6, were performed "at the most limiting condition that occurs at the end-of-cycle, with power peaked
221-2
'221.11 (4.4.4.6) 221.12 (4.4.4.5) 221.13 (4.4.4.6) 221.14 (4.4.5.1) to the bottom of the core...".
Indicate which cycle is being referred to (i.e., first, second or equilibrium).
If it is other than equilibrium, provide results for the end of equilibrium cycle or justify why the results pre-sented represent worst-case conditions.
Provide the power profile and the void reactivity coefficient used for the analysis.
In discussing the FABLE code on page 4.4-23, you state that "As new experimental or reactor operating data are obtained, the model is refined to improve its capability and accuracy."
This means that comparison of old versions of the model with
- data, as given 'in Figure 4.4-4, are meaningless for Susquehanna if it has been analyzed with an updated version.
Are the com-parisons of the model with data, as given in Figure 4.4-4, based on the same version of the model as was used for Susquehanna' If not, provide comparisons using the Susquehanna model.
In addition, provide a description of the code or reference a
prior licensing submittal (other than the KAPL reports on STABLE).
On page 4.4-23, the REDY code is referenced as the model used to perform system stability calculations.
You also state that the model is periodically refined as new experimental or reactor operating data are obtained.
Is the version of REDY used for Susquehanna described in NEDO-10802?
If not, describe the changes.
BWR applicants have traditionally included operational design guidelines for decay ratios and damping factors used in stability analyses.
These design guides have been omitted from your dis-cussion of stability.
Are operational design guidelines no longer applicable?
If not, explain why.
Your response to f221.1 is unacceptable.
The staff believes that the state-of-the-art has progressed such that effective LPM systems can be installed in commercial LWRs.
The rationale for this is documented in draft Regulatory Guide 1.133 (Loose-Part Detection Program for the Primary System of Light-Hate@-
Cooled-Reactors).
Additional rationale clarifying the staff position can also be found in a letter, Vassallo to J.E.
Mecca (Pugent Sound Power and Light Company)
"Skagit Nuclear Power
- Project, Units 1
8 2" dated July 20, 1978 (Docket Nos. 50-522/523) available in the NRC public document room.
A number of LWR's, including BWR's, at the same stage of licensing as Susquehanna, have committed to the installation of a LPN system.
In addition, it is required by the staff that a
LPM system be installed and operational prior to startup of the reactor.
Therefore, please provide the information requested in f221.1.
221-3 221.15 (Table 4.4-6)
Table 4.4-6 describes uncertainties used in the statistical analysis which is performed to establish the fuel cladding integrity safety HCPR limit.
Provide a discussion of and reference where possible the experimental data bases used to derive the uncertainty values listed.
In particular, describe the applicability of these values to the Sx8, two-water rod assembly design.