ML20140G613
| ML20140G613 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/11/1997 |
| From: | Hansen A NRC (Affiliation Not Assigned) |
| To: | Jeffery Wood CENTERIOR ENERGY |
| References | |
| TAC-M97902, NUDOCS 9706160379 | |
| Download: ML20140G613 (5) | |
Text
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5 s
Cune ti, 1997 Mr. John K. Wood Vice President - Nuclear, Davis-Besse Centerior Service Company c/o Toledo Edison Company Davis-Besse Nuclear Power Station 5501 North State Route 2 Oak Harbor, OH-43449-9760
SUBJECT:
DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION, LICENSE AMENDMENT. REQUESTS 95-27. 95-24, AND 96-14 RELATED TO INSTRUMENTATION TECHNICAL SPECIFICATIONS (TAC NOS.
M97441, M97902, AND M98520 RESPECTIVELY)
Dear Mr. Wood:
By letters dated December ll. 1996. January 30 and April 18. 1997, you
. submitted license amendment requests (LAR). 95-27, 95-24. and 96-14.
respectively, related to instrumentation Technical Specifications for the Davis-Besse Nuclear Power Station.
The NRC staff is currently reviewing these requests and has determined that additional information is necessary to complete the review process.
The NRC staff would like to meet with your staff to discuss these requests.
Jarticularly the instrument drift study and setpoint analysis-described in
_AR 96-14.
The enclosed questions have been posed by the NRC staff to provide i
guidance for your preparation for this meeting.
Please have your staff contact me at (301) 415-1390 to arrange this meeting.
Sincerely, Original s'igned by:
hh bk bbbbb Allen G. Hansen, Project Manager Project Directorate III-3 Division of Reactor Projects III/IV Office of Nuclear Reactor Regulation Docket No. 50-346 DISTRIBUTION:
Docket. File OGC
Enclosure:
Request for Additional PUBLIC ACRS Information PD3-3 R/F JRoe EAdensam (EGA1)
(
cc w/ encl:
See next page GMarcus b, M l
) g. j,1,2 GGrant, RIII L
DOCUMENT NAME: G:\\DAVISBES\\DB98520.RAI To receive a copy of this document, indicate in the box: "C" = Copy without enclosures "E" = Copy wnh enclosures "N"
= No copy 0FFICE LA:PD3-3_,l E PM:PD3-3 A E BC:ESe lE NAME CBoyle C O AHansend)t?&
JWerijt'51 DATE (p /f/97 0 6//o/97 "
4//f/97 0FFICIAL RECORD COPY 9706160379 970611 PDR ADOCK 05000346 P
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- a Cune 11, 1997 Mr. John K. Wood Vice President - Nuclear. Davis-Besse Centerior Service Company c/o Toledo Edison Company Davis-Besse Nuclear Power Station 5501 North State Route 2 Oak Harbor. OH 43449-9760
SUBJECT:
DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION. LICENSE AMENDMENT REQUESTS 95-27, 95-24. AND 96-14 RELATED TO INSTRUMENTATION TECHNICAL SPECIFICATIONS (TAC NOS.
M97441, M97902. AND M98520. RESPECTIVELY) j
Dear Mr. Wood:
By letters dated December 11, 1996. January 30 and April 18, 1997. you submitted license amendment requests (LAR) 95-27. 95-24 and 96-14, respectively, related to instrumentation Technical Specifications for the Davis-Besse Nuclear Power Station. The NRC staff is currently reviewing these requests and has determined that additional information is necessary to complete the review process.
The NRC staff would like to meet with your staff to discuss these requests, 3articularly the instrument drift study and setpoint analysis described in
)
l
_AR 96-14.
The enclosed questions have been posed by the NRC staff to provide guidance for your preparation for this meeting.
Please have your staff j
contact me at (301) 415-1390 to arrange this meeting.
Sincerely.
Original signed by:
Allen G. Hansen. Project Manager Project Directorate III-3 l
Division of Reactor Projects III/IV Office of Nuclear Reactor Regulation Docket No. 50-346 DJ.STRIBUTION:
Docket File OGC
Enclosure:
Request for Additional PUBLIC ACRS Information PD3-3 R/F JRoe l
EAdensam (EGA1)
I cc w/ encl: See next page GMarcus i.
GGrant RIII j
DOCUMENT NAME:
G:\\DAVISBES\\DB98520.RAI i
To receive a copy of this document, indicate in the box: "C" = Copy wthout enclosures "E" = Copy with enclosures "N" i
= No copy 0FFICE LA:PD3-3
,l E
PM:PD3-3, 1 E BC:ECS r lE i
NAME CBoyle C{@
AHansend)tPD.
JWeriltFi J
DATE
& /4 /97 0 f //o/97 -
4//f/97
)
0FFICIAL RECORD COPi '
J
r John X. Wood Davis-Besse Nuclear Power Station l
Toledo Edison Company Unit 1 4
cc:
l Mary E. O'Reilly Bureau of Radiological Health Robert E. Owen, Chief Centerior Energy Corporation 300 Madison Avenue Service l
Toledo. Ohio 43652 Ohio Department of Health P. O. Box 118 James L. Freels Columbus Ohio 43266-0118 Manager - Regulatory Affairs Toledo Edison Company James R. Williams Davis-Besse Nuclear Power Station Chief of Staff 5501 North State - Route 2 Ohio Emergency Management Agency Oak Harbor. Ohio 43449-9760 2855 West Dublin Granville Road Columbus. Ohio' 43235-2206 l
Gerald Charnoff. Esq.
Shaw. Pittman, Potts Roy P. Lessy, Jr., Es i
and Trowbridge Andrew G. Berg, Esq. q.
1 2300 N Street. N.W.
Akin Gump,. Strauss. Hauer i
Washington, D.C.
20037
& Feld, L.L.P.
1333 New Hampshire Ave., NW, Ste. 400 Regional Administrator Washington, D.C.
20036 U.S. NRC, Region III 801 Warrenville Road Ohio Environmental Protection Agency Lisle. Illinois 60523-4351 DERR--Compliance Unit ATTN:
Zack A. Clayton Robert B. Borsum P. O. Box 1049 Babcock & Wilcox Columbus Ohio 43266-0149 Nuclear Power Generation Division 1700 Rockville Pike, Suite 525 State of Ohio Rockville Maryland 20852 Public Utilities Commission 180 East Broad Street Resident Inspector Columbus. Ohio 43266-0573 U. S. Nuclear Regulatory Commission 5503 North State Route 2 Attorney General Oak Harbor. Ohio 43449 Department of Attorney 30 East Broad Street James H. Lash, Plant Manager Columbus Ohio 43216 Toledo Edison Company Davis-Besse Nuclear Power Station President. Board of County 5501 North State Route 2 Commissioner of Ottawa County Oak Harbor. Ohio 43449-9760 Port Clinton, Ohio 43252 Donna Owens Director Ohio Department of Commerce Division of Industrial Compliance Bureau of Operations and Maintenance 6606 Tussing Road P 0. Box 4009 Reynoldsburg, Ohio 43068-9009 l
'~
REQUEST FOR ADDITIONAL INFORMATION REGARDING 4
LICENSE AMENDMENT REQUESTS (LARs) 95-27. 95-24. AND 96-14 DAVIS-BESSE NUCLEAR POWER STATION. UNIT 1 (1)
Please provide a discussion of the instrument setpoint methodology.
including the following items:
4 a.
Framatome document for instrument string error; b.
Allowable value calculation, especially the use of two allowable values for the same parameter; and c.
Conformance to Regulatory Guide 1.105.
(2)
Please provide details on the acceptability of the instrument drift-exceeding the design basis / reference uncertainty during an 18-month fuel cycle, and how this will be controlled during a 24-month fuel cycle.
(3)
Since some of the instruments will be calibrated at 18-month intervais, calibration for these instruments will have to be done on-line. Discuss the procedural aspects of the on-line calibration, especially addressing L
any effects on plant safety as well as potential plant transients and/or trips.
(4)
When a sensor requires calibration.'the calibration uses at least seven readings along the instrument span.
Since these points are not independent, the same calibration check is repeated.
Thus, it appears that the number of points used in some statistical analyses was significantly inflated. Any analysis that uses more than one point from l
each instrument at each calibration check is not valid.
For example, in LAR 95-24. testing normality (Attachment 6) uses 154 readings when there are only 22 sensor tests conducted.
Please discuss.
(5)
Charts with duplicate readings (such as Attachment 8) are not printed clearly. Two readings at the same calibration interval could represent different sensors or repetitions of the same sensor.
Please clarify.
(6)
The use of time since last calibration for the purpose of predicting drift appears to be inappropriate.
Such analysis ignores sensor tests that " failed" (that is, required recalibration) at some intermediate step, and so projects an over-optimistic view of the instrument drift.
The inclusion of time since last calibration could confuse the reader.
Please address this issue.
l (7)
Even if drift is time-independent, the uncertainty associated with the drift is time-dependent. Attachments 8, 9. and 17 show that as the time i
between tests increases, so does the spread of the data.
Please address this issue.
(8)
Two tests were used for normality. The first is the W test (for ns50) or the D' test (for n>50). The second uses " bins" to stratify the data.
i l
l r
b Whereas the first test is objective, the second test appears to be arbitrary (it depends on how the bins are defined) and insensitive to departure from normality.
L The use of both tests is a concern.
If the two tests-agree, then the second test is redundant. However, if the two tests do not agree then the binning method should be difcarded. When the results conflict, the
" bin" method is relied on.
Please discuss.
4 i
(9)
On page 7 of Attachment 1. Item (e) states that the analysis uses the F test to check the homogeneity of variances.
The proposed test compares the variance associated with a long calibration interval to that of the shortest interval.
However, other variances may also need comparison.
For exam)le. Attachment 8 suggests that the variance at 18 months is
)
higher tlat the variance at 19 months. Therefore, it appears that a comparison against 18 months (rather than the longest calibration i
interval) is warranted.
Perhaps the largest and smallest variances should be compared. Also, a multiple-variance test, such as Bartlett's test for homogeneity of variances. ought to be considered.
Please address these issues.
(10) The results of the F test are not reported.
Please discuss.
(11) Variances for different calibration intervals do not appear to be alike, Conservatively, the higher variance, rather than the " pooled" standard deviation, ought to be used.
Even then, it appears that the
?'
extrapolation to 30 months is not appropriate.
Please explain.
9 (12) Some of the sensors were tested immediately after being put in service (readings at or near 0 months).
Please explain the rationale for these tests.
(13) Please be prepared to provide a step-by-step review of a sample data calculation for at least one sensor during the proposed meeting.
.