ML19351G080
| ML19351G080 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 11/03/1980 |
| From: | Morisi A BOSTON EDISON CO. |
| To: | Brunner E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML19351G078 | List: |
| References | |
| 80-277, NUDOCS 8102230083 | |
| Download: ML19351G080 (3) | |
Text
- -. _ _.
_m___.
m._ _ -=
j 4
COGTON EDIDON COMPANY J
OtNERAL OFFICas 800 GovLsTom Statt?
SO STON. MassacMust??s 0219 9 A. V. M O Riel MANAGER NUCLEAR OPCRATIONS SUPPCRT DEPARTMENT November 3, 1980 BECo. Ltr. #80-277 I
Mr. Edlon J. Brunner, Chief Reactor Operations and Nuclear Support Branch U.S. Nuclear Regulatory Commission i
631 Park Avenue King of Prussia, PA.
19406 l
License No. DPR-35 Docket No. 50-293 Response to IE Inspection #80-26
Dear Sir:
Your letter dated October 7,1980, " Inspection 50-293/80-26" contained three (3) items of non-compliance.
Boston Edison Company's responses to those items are presented in Attachments A & B to this letter.
Pursuant to Section 2.790(d) of 10 CFR, Part 2, we respectfully request with-holding the infomation provided in Attachment B to this letter from public inspection. Withholding from public inspection does not affect the right, if any, of persons properly and directly concerned with the project to inspect the informa tion.
Very truly yours, At/.niewtJGJs) 81 0223 0@
C i
Attachment A Infraction Technical Specification 2.1.A.1.a states in part that:
"... the APRM flux scram trip setting shall be :S(.55 W + 55% 2 loop where S = setting in per-cent of rated thennal power (1998 mwt); W = percent of drive flow."
Contrary to the above, on July 28, 1980, the reactor wa's operating in the RUN mode with the APRM flux scram settings (at 100% drive flow) as high as 122.9 percent of rated thermal power.
Response
Calibration techniques in effect prior to this inspection pennitted a plus or minus five percent instrument tolerance window. Tolerances or variations in the positive direction without recalibration permitted the operation cited above.
To correct this problem the APRM Gain Adjustment Factor (AGAF) on the APRM's were intnediately recalibrated to keep them with.950 to 1.000.
The affected procedures numbers 9.1 and 2.1.15 were revised as of October 1, 1980 to maintain these AGAF calibration limits.
This means that the APRM's are calibrated to actual power or up to 5% above actual power thereby limiting the scram setting to 120% of rated thermal power. We are currently in full compliance.
Deficiency Technical Specification 2.1.A.1.a requires that the APRM flux scram trip settings not exceed 1201 of rated thermal power for all combinations of loop flow and core power.
Technical Specification 6.9.B.2.a requires a 30 day report to the NRC whenever a reactor protection system instrument setting is found to be less conservative than those established by the Technical Specifications, but which do not prevent fulfillment of the functional requirements of affected systems.
l Contrary to the above, a 30 day report to the NRC was not made when the Channel
'F' APRM 120% clamp trip setpoint was found to be outside the technical spec-ification limits during perfonnance of Procedure 8.M.1-4 "APRM Flow Bias Signal Calibration" Revision 6, on July 1,1980.
Resoonse We do not agree with the inspector's findings relative to this item and as described below, believe this item should be removed as a " deficiency" from the subject inspection report.
On July 2,1980 the Operation Review Committee (0RC) for PNPS reviewed this event and detennined that, since there' are installed spare channels in both RPS trip systems for initiating a scram via High APRM Flux, that no degradation from the one out of two, taken twice, safety reliability criteria of the RPS Trip system occurred.
On October 22, 1980 the ORC again reviewed this event and concurred with the original finding.
Technical Specification TABLE 3.1.1 requires that a minimum of two operable instrument channels per trip system be operable.
This require-ment was satisfied with channel
'F' operable.
l
g,.
The ORC does not believe it is the intent of Technical Specification 6.9.B.2.a to report single channel instrument drif t discovered as a result of testing when the function affected has installed and operable spare channels.
G
..