ML19260B456
| ML19260B456 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 10/02/1979 |
| From: | Counsil W CONNECTICUT YANKEE ATOMIC POWER CO. |
| To: | Brunner E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML19260B453 | List: |
| References | |
| NUDOCS 7912100196 | |
| Download: ML19260B456 (3) | |
Text
4 CONNECTICUT YANKEE ATOMIC POWER COMPANY BERLIN, CO N N E CTIC U T P.O. BOX 270 H ARTFORD. CONNECTICUT 0610t Tatappo=r October 2, 1979 Docket No. 50-213 U. S. Nuclear Regulatory Commission Region 1 Office of Inspection and Enforcement 631 Park Avenue King of Prussia, Pennsylvania 19406 Attn:
Mr. E. J. Brunner, Chief Reactor Operations & Nuclear Support Branch
Reference:
Letter, E. J. Brunner to W. G. Counsil dated September 13, 1979 Inspection 50-213/79-15 Decr Mr. Brunner:
The following explanation concerning the item of non-compliance described in the above reference is submitted to your of fice pursuant to the provisions of Section 2.201 of the Nuclear Regulatory Commission " Rules of Practice",
Part 20, Title 10, Code of Federal Regulations.
Infraction Based on the results of an NRC Inspection conducted on August 14-16, 1979, it appears that one of your activities was not conducted in full compliance with the corditions of your NRC Facility !icense No. DPR-61, as indicated below.
This item is an infraction.
Technical Specification Table 4.2-1 (1), requires, in part, that the nuclear power reactor trip function be tested twice a month.
1519 293 7912100
. Contrary to the above, the plant was operated in the three loop mode permitted by Technical Specifications, from July 14-23, 1979, with reduced overpower trip setpoints of less than or equal to 84 percent power, without testing the operability of the trip setpoints since February, 1979.
Responge Each of four available power range channels contains three overpower trip setpointa,
<25%, <84% and <109% of full power.
Selection of a particular trip setpoint is dependent upon the power level at which the plant is operating, i.e., power less than 25% the < 25% setpoint is selected, power between 25% and 84% the < 84% setpoint is selected and whenever power level is greater than 84% th. < 109% trip setpoint is selected.
Connecticut Yankee Safety Techn. cal Specifications, Section 4.2, Table 4.2 1, requires that the nuclear power channels trips be tested twice each month.
The testing is implemented by using surveillance procedure SUR 5.2-9.
The required surveillance was performed on July 12, 1979 with the plant at 100% power. Customarily the trip setpoint above the operating power level is the only one tested because the lower setpoint trip (s) are already activated.
Only the position selector s, itch prevents the signal from continuing through the reactor trip matrix.
On July 14, 1979 because of a failed seal on #3 Reactor Coolant Pump the plant reduced power level to 65% and removed the #3 loop from service.
4t this time the trip setpoint selector switch was placed in the mid
(< 84%) position.
It remained at this setting until the plant returned to a power level on July 23, 1979 except during plant shutdown and startup operations on the 22nd. The setpoints were checked during the precritical instriment checks on the 22nd.
The next scheduled surveillance test was performed on July 26, 1979 at 100% of full powe r at which time only the < 109% setpoint was tested.
Operating at a reduced power level is a very infrequent occurrence at Connecticut Yankee.
Because the period at reduced power level fell between scheduled surveillance tests, testing of the < 84% trip setpoint was overlooked.
1519 294
e.
The omission was discovered as a result of IE Inspection 79-15 and although resolved to the satisfaction of the Inspector became the subject of a Notice of Violation at the " Infraction" level.
To preclude a recurrence, Surveillance Procedure SUR 5.2-9, entitled
" Nuclear Instrumentation Power Range Bi-Monthly Test, was revised on September 15, 1979 to include the necessary steps to test the applicable setpoints.
Very truly yours, CONNECTICUT YANKEE ATOMIC POWER COMPANY (fl i
W. G. Counsil, Vice-President 1519 295