ML20084T475
| ML20084T475 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 08/21/1973 |
| From: | Sewell R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Oleary J US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| AO-11-73, NUDOCS 8306230217 | |
| Download: ML20084T475 (1) | |
Text
..
o Gx O
s y
{;3 G
h
/[d
_3' x
2ts p
e CORSumBIS q fS. Uce mg
[!
$t POW 8f G 2 31973> I 3
r inis"
'ca:
Company 8
N bl Sectea f-O General Offices:
et D" i Avenue. Jackson, Machigan 4 9201. Area Code 517 788-0550 August 21, 1973 Mr. John F. O' Leary Re: Docket 50-255 Director of Licensing License DPR-20 US Atomic Energy Commission A0-11-73 Washington, DC 205h5
Dear Mr. O' Leary:
This letter is written to report an abnonnal occurrence involving the nuclear instrumentation start-up channels at the Palisades Plant.
l l
On August 11, 1973, during plant shutdown for investiga-tion of the Palisades Plant "B" steam generator primary to secondary l
1eakage, both nuclear instrument start-up channels did not function properly. The primary coolant system was borated to cold shutdown I
concentration and plant cooldown was initiated.
A new start-up chamber has been installed. This new cham-ber, along with the two intermediate channels, provides at all times adequate visibility of the core.
This failure is typical of several previous failures ex-l perienced with start-up channels.
(These previous failures were l
described in our TWX to the Directorate of Licensing dated 12/11/72 and 12/21/72, Proposed Technical Specifications Change No 4 dated 12/21/72 and letter dated 5/29/73.)
Consumers Power Company.ana the vendor are continuiug to investigate these failures in order to resolve these difficulties.
As an interim corrective measure, we have ordered two supposedly longer lived units. These units will not be available at the plant site for at least a month. In addition, we are conducting experi-ments to identify, as precisely as possible, the operating environ-ment of these detectors.
Yours very truly, 8306230217 730821 PDR ADOCK 05000 S
Ralph B. Sewell (Signed)
RBS/mel Ralph B. Sewell Nuclear Licensing Administrator CC: BHGrier, USAEC
,t f(
/
qv
/, c' -
841..
b COPY SENT REGION,
2