ML20073B573
| ML20073B573 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 03/09/1983 |
| From: | Crouse R TOLEDO EDISON CO. |
| To: | Norelius C NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| Shared Package | |
| ML20073B569 | List: |
| References | |
| L-334, NUDOCS 8304120464 | |
| Download: ML20073B573 (3) | |
Text
ca.
Docket No. 50-346 TOLE 00 it)lElt)l4 License No. NPF-3 Acaum P. Cnast Serial No. 1-334 ve. pr 4
Nxww uim esneai March 9, 1983 Mr. C. E. Norelius, Director Division of Engineering & Technical Programs United States Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137
Dear Mr. Norelius:
Toledo Edison acknowledges receipt of your February 10, 1983 letter (Log 1-737) and enclosures, Appendix, Notice of Violation and report l
50-346/82-34 (DPRP) referencing one (1) violation and one (1) item of concern.
Following an examination of the notice of violation, Toledo Edison herein offers information regarding the item of violation.
Violation:
Technical Specification 4.2.1 requires that the Axial Power Imbalance be determined to be within limits once per hour when the Axial Power Imbalance alarm in inoper-able and the unit is in Mode 1 at greater than 40% power.
l Contrary to the above, for more than two months, the Axial Power Imbalance alarm was inoperable and the Axial Power Imbalance was not calculated hourly.
Initial calibration of the alarm was not performed until more than two months of operations at greater than 40% power and no method existed for determining operability of the alarm or for alarms covered by Technical Specifications 4.1.2.1.1; 4.1.3.2.1; 4.1.3.3; 4.1.2.6; A.1.3.9; or 4.2.4.
l Response: (1) Corrective action taken and results achieved - Tests were written to check the computer alarms to assure the " alarms package" would recognize an out-of-limit value and cause an alarm in the Control Room. The computer alarms package j
monitors quadrant power tilt (Tech. Spac. 4.2.4), axial power imbalance (Tech, Spec. 4.2.1), and all control rod positions (Tech. Spec. 4.1.3.6 and 4.1.3.9). All of the computer alarms worked properly except the imbalance limit slarm.
It was found the limits in the data were based on percent full power and the calculated imbalance used to compare to the limits was in a decimal fraction of full power. This problem was immediately corrected so no hourly THE TOLEDO EDISON COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO. OHIO 43652 8304120464 830408 MAR l' 4 g33 PDR ADOCK 05000346
[~
O PDR,_
.s b
Docket No. 50-346-
- License No. NPF-3 Serial'No.'l-334 March 9, 1983 Page 2 calculation was required. The test on the imbalance alarm was repeated and the results were acceptable.
The asymmetric rod fault alarm circuitry (Tech. Specs.
4.1.3.1.1; 4.1.3.2.1.; and 4.1.3.3) was tested as part of the control rod drive insertion time test. The alarm functioned properly.
Past operating experience has shown the control rod drive sequence alarms circuitry (Tech. Spec. 4.1.3.6) is functional.
The Davis-Besse reactor is run "un-rodded" (i.e., all control rods almost completely withdrawn from the core).
Normally, the only time the reactor would be critical with the control rods in the over-lap region would be during zero power physics testing.
(2)
Corrective action to be taken to avoid further noncompli-ance - A procedure is being written to ' test the appropriate parts of the computer alarms package any time a limit on tilt, imbalance, or rod insertion is changed. When a limit is changed the associated alarm'is to be considered inoper-able until the test has been completed. The asymmetric rod fault alarm circuitry test will be incorporated in the control rod exercise monthly test. The zero power physics test will be modified to incorporate a check of the control' rod drive sequence alarm circuitry operability.
(3)
The date when full compliance is achieved - The procedure.
to test the various parts of the alarms package and the control rod exercise monthly test will be modified by April 15, 1983..The zero power physics test will be modified to check sequence alarm circuitry during its review for cycle 4 physics testing.
Regarding the item of concern related to' safety evaluations,. Toledo Edison's response is as follows:
The safety evaluation was written assuming that appropriate
~
testing would be performed to verify the appropriate operability requirements of valve AF-1.
The assumed tenting was not per-
~
formed appropriately. 'This incident points to a general incon-sistency in safety evaluation performance and review. We feel this inconsistency is a result of-each organization within the
. Nuclear Mission having its own procedure 1for performing safety evaluations.
'e' Docket.No. 50-346 License No. NPF-3 Serial No.1-334 March 9, 1983:
Page-3 i
. Toledo Edison will, therefore, generate a single procedure-for safety evaluations for use throughout the Nuclear Mission. This
-procedure will-contain a provision for adequate review by the, Station Review Board and the Company Nuclear Review Board's Safety Evaluation Committee.
1 Very truly yours, f f h :
RPC:DJD:SGW:RFP:nif-cc: DB-1 NRC Resident Inspector D
I i
{
I
~
L 4...
..