ML19247B235
| ML19247B235 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 07/02/1979 |
| From: | Reid R Office of Nuclear Reactor Regulation |
| To: | Roe L TOLEDO EDISON CO. |
| References | |
| NUDOCS 7908080213 | |
| Download: ML19247B235 (3) | |
Text
._
ga "'%gS UNITED STATES
+.
e,f NUCLEAR REGULATORY COMMISSION h'Q p Q
!,' N(%
i*l. a E
usuincros. o. c. 2osss 2
Y It i,%,, f l July 2, 1979 Docket No. 50-346 Mr. Lowell E. Roe Vice President, Facilities Development Toledo Edison Company Edison Plaza 300 Madison Avenue Toledo, Onio 43652
Dear Mr. Roe:
In determining the peak kilowatt per foot in the red drop test for Davis-Sesse Nuclear Power Station - Unit No.1, your staff first evaluated the Linear Heat Generation Rate (LHGR) to be too high. This test was per-formed at 40% power and the LHGR was calculated by extrapolation to the 100% power level througn the use coefficients provided by Babcock and Wilcox.
However, by using the on line computer which receives its input frca incare detectors the calculated LHGR values are within allowable limits. The NRC Office of Inspection and Enforcement Region III Inspector raised questions as to the adequacy of the data reduction methods and, therefcre, the acceptability of the rod drop tests.
We have been reviewing this concern and in order for us to complete our review we need additional '1forna tion. Therefore, we request you provide the enclosed requested information or schedule for providing it within 30 days of receipt of this letter.
Sincerely, M./h h' N
^<
Robert W. Reid, Chief Operating Reactors Branch d4 Division of Coerating Reactors
Enclosure:
Request for Acditional Infonnation cc w/ enclosure: See next page 4 j '}
U.'d 7908080'2./ -.,_
7
\\
Toledo Edison Company CC:
Mr. Donald H. Hauser, Esq.
The Cleveland Electric Illuminating Company P. O. Box 5000 Cleveland, Ohio 44101 Gerald Charnoff, Esq.
Shaw, Pittman, Pot ts and Trowbridge 1800 M Street, N.W.
Washington, D.C.
20036 Leslie Henry, Esq.
Fuller, Seney, Henry and Hodge 300 Madison Avenue Toledo, Ohio 43604 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Power Generation Division Suite 420, 7735 Old Georgetown Road Bethesda, Maryland 20014 Ida Rupp Public Library 310 Madison Street Port Clinton, Ohio 43452 r]O [OJb A:
i
Enclosure RECUEST FOR ADDITIONAL INFORMATION CONCERNING DAVIS-BESSE UNIT N0. 1 DETERMINING CORE PARAMETERS FRCM R00 DROP TEST 1.
Provide comparisons of calculated and measured radial peaking factors for the " dropped rod" tests at both of the 50% and the 0% wi hdrawn positions.
t It is preferrable that these be submitted in the forn of core macs.
2.
Provide the measured values of maximum linear heat rate and minimum DNBR for the " dropped rod" cases.
3.
How did you account for the uncertainties in these measurements?
Explain quantitatively what factors are accounted for in these uncertainties.
4.
How was the data measured at 40% powar extrapolated to 100% power?
5.
We have studied BAW-10123 Nuclear Acolication Software Packace for 205-fuel assembly plants and assume :nat tne racial local peaking tactors are cal-culated in a similar manner for 177-fuel assembly plants. Describe in detail how radial local peaking factors are calculated for the " dropped rod" situation which is very different from " fuel-cycle design rod positions" as discussed in section 3.8.2.
If a multiplicative correction factor was used, please provide details as to how it was calculated. Also describe how'you account for the uncertainties in the radial local peaking factor.
5.
Are the values of radial local peaking factor conservative? If this is the case, justify this conclusion.
If not, show how this is taken into account.
7.
It has been stated that there are other conservatisms in the process c0mouter calcul atio n.
Explain in detail (quantitively) what these conser-vatisms are and what assurance there is that credit for these has not and cannot be taken elsewhere.
S.
Are there other factors or parameters tsed in
- 'e process computer that may not be. conservative? If so, explain hcw you justify the process computer calculation.
D' $
- o
,