IR 05000213/1993008
| ML20058C926 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 11/15/1993 |
| From: | Blough A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Opeka J CONNECTICUT YANKEE ATOMIC POWER CO. |
| References | |
| NUDOCS 9312020628 | |
| Download: ML20058C926 (2) | |
Text
{{#Wiki_filter:, m,r ' . L&) >; .. , Tad f SM ' , , Docket No. 50-213 Mr. John ; Executive Vice President - Nuclear Connecticut Yankee Atomic Power Company P.O. Box 270 Hartford, Connecticut 06141-0270
Dear Mr. Opeka:
, SUBJECT: NRC Inspection Report No. 50-213/93-08 This refers to your letter dated August 19, 1993, in response to our July 26,1993, letter which transmitted a deviation involving an emergency diesel generator non-emergency trip that did not function as described in your Updated Final Analysis Report (UFSAR).
Thank you for informing us of the corrective actions documented in your letter. These actions will be examined during a future inspection of your licensed program.
We appreciate your cooperation.
Sincerely, A. Randolph Blough, Chief Projects Branch No. 4 Division of Reactor Projects 9312O20628 931115 PDR ADOCK 05000213 G PDR I
- .. ... ' , NOV 151993
. , , .
Mr. John : bec w/ encl: ! Region I Docket Room (with concurrences) j
bec w/enci (VIA E-MAIL): J. Stolz NRR/PD I-4 l V. Mcuee, OEDO ! A. Wang, PM, NRR i i i i ! ! i ! ! !
! , f
i ! i i f
, i
I
i - ( RI:DRP RI:DRP RI:DRP ! Blumberg Doerflein Blough 11/10'93 11/0/93 11/4/93 . OFFICIAL RECORD COPY G:\\RL9308 ) i . >
', ,
- %
l ' NORTHEAST UTILETIES cener.i Omce.. s ioen sire.i. s.rnn. conn.ci>cui ,
$ a* 5 =* P.O. BOX 270 . " ' * * * * ' ' * * " ' * " " * * * " HARTFORD. CONNECTICUT 06141-0270 L L J [,[[ [ O C $ C (203) 665-5000 f August 19, 1993 Docket No. 50-213 B14588 r U.S. Nuclear Regulatory Commission
Attention: Document Control Desk Washington, DC 20555
Gentlemen: Haddam Neck Plant Response to a Notice of Deviation NRC Inspection Report No. 50-213/93-08 By letter dated July 26, 1993,"' the NRC Staff transmitted Inspection Report No. 50-213/93-08, a Notice of Deviation.
The deviation involves an emergency diesel generator, non-emergency trip that did not function as described in the Updated Final Safety Analysis Report.
The NRC Staff requested that the Connecticut Yankee Atomic Power Company (CYAPCO) respond to the Notice of Deviation within 30 days of the date of the notice. CYAPC0 hereby provides its response in Attachment 1.
CYAPC0 trusts that the information provided herein fully addresses the NRC Staff's concern regarding this issue.
Please contact us if you have any questions.
Very truly yours, CONNECTICUT YANKEE ATOMIC POWER COMPANY FOR: J. Executive Vice President - 'd 0 /S A By: / W. D. Romberg C Vice President cc: T. T. Martin, Region I Administrator A. B. Wang, NRC Project Manager, Haddam Neck Plant W. J. Raymond, Senior Resident Inspector, Haddam Neck Plant (1) A.
Randolph Blough letter to John F.
Opeka, "NRC Inspection Report No. 50-213/93-08," dated July 26, 1993.
OS3422 REV.448 q#>torm
r- ' . .
! . - . ! ' i h Docket No. 50-213 l B14588 i
i , f f f ,
Attachment No. 1 Haddam Neck Plant Response to a Notice of Deviation - ; NRC Inspection Reoort No. 50-213/93-08 . ! , , ,
,
. I s August 1993 , b ! ! r i , ~ .
,
.. . .~ U.S. Nuclear Regulatory Commission B14588/ Attachment 1/Page 1 August 19, 1993 Haddam Neck Plant Response to a Notice of Deviation NRC Inspection Report No. 50-213/93-08 Description of Deviation The Haddam Neck Updated Final Safety Analysis Report, Section 8.3.1.1.5, " Emergency AC Power System Description" states, in part, that when the emergency diesel generator is running in a normal non-emergency mode, all trips remain in service and are capable of tripping the diesel generator. These trips include the generator loss of field trip.
Contrary to the above, on May 25, 1993, during a normal test run of the 'A' emergency diesel generator, the generator field was lost and the diesel generator output breaker did not trip.
The licensee subsequently identified that the currently installed generator loss of field trip circuit does not trip the diesel generator during the normal non-emergency mode of operation.
Reason for the Deviation The deviation was the result of a lack of understanding of the vendor's design when the units were installed in 1970.
The diesel ge'ierator instruction book stated the "N0 FIELD" alarm / trip indicates there is no field or generator voltage. As such, this function was interpreted to be a loss of field feature.
This lack of understanding was carried over into the Updated Final Safety Analysis Report (UFSAR).
As a result of the recent excitation system failure, a detailed review of the circuitry was performed. This more detailed review revealed that the original design of loss of field protection was only present during the first several seconds of an emergency start to detect a field flash failure.
Corrective Steps That Have Been Taken and Results Achieved CYAPC0 has initiated Engineering Work Request #93-MS099 to install a standard loss of field relay.
This relay will be in service for surveillance runs and bypassed under accident / loss of power conditions, which is in agreement with the UFSAR as presently written.
In the mean time, a change to the UFSAR will be processed to reflect the present condition.
The remaining circuitry, in the emergency diesel generator protective scheme, was inspected and no other deviations were found.
Corrective Steps That Will Be Taken To Avoid Further Deviations This deviation in the UFSAR was not a safety related issue and was due to a lack of understanding of the actual loss of field design feature.
This issue is judged to be an isolated case of low safety significance.
. . ,. . . ' . - . . U.S. Nuclear Regulatory Commission ' B14588/ Attachment 1/Page 2 ' August 19, 1993 With the recent establishment of a system engineering program at the Haddam Neck , Plant, we expect additional gains in system understanding, testing, and improvements.
Considering the low safety significance of this isolated
deviation, we do not believe that any additional corrective measures are
necessary at this time.
, I Date When Full Comoliance Will Be Achieved
The UFSAR change request will be issued prior to the next annual revision. The . installation of the standard loss of field relay is scheduled for the next refueling outage.
l i
! l i i ! i ! i l
I , l' i
i }}