ML20084T629
| ML20084T629 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 08/02/1973 |
| From: | Sewell R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Oleary J US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20084T623 | List: |
| References | |
| AO-4-73, NUDOCS 8306230327 | |
| Download: ML20084T629 (3) | |
Text
_ _ _ _ _ _ _ __
1/ l.-
g
~
- CODSu m 8IS n
Li i POW 8r Q
/ C0mpany s n.r.i omc..: 2i2 w.. u cnj M)+
l s. Michigan 49201. Area Code S17 788-0550
/
O fj August 2, 1973
/
${,
^
i 0"
b2-Augg 1973%ull u.s. a N
Mr. John F. O' Leary 4
Re:
gg 350_255 Director of Licensing to US Atomic Energy Comission Washington, DC 20545
Dear Mr. O' Leary:
The following describes Palisades Abnormal Occurrence h-73 which consis,ted of one control rod being inserted slightly beycnd the power dependent insertion limit (PDIL) as defined in the Technical Specifications.
The incident occurred at 0619 on July 23 with the plant at about 80% power after a one-day outage. At that time, a power escala-
~
tion of 10% per hour was in progress and core xenon was burning out rapidly.*
While the control rods were being withdrawn during power escalation, a prepower dependent insertiWafahi]P'PDIL) came in.
This alarm is fixed 10 inches above the final PDIL limit. The opera-tor immediately started borating in small batches (35, 25, 20 gallons) y to bring the control rods back out. However, with xenon burning out 4M
/
rapidly, the boration was apparently too slow and the alarm point was /L'"w.o, Ag increasing at the same time because of the pcVer increase. Control 56g rod No 38, which was slightly behind the rest of the controlling groupp.rf, g "'-
ended up 0.1 inch below the alarm limit for that power (78.3 inc Y en k Additional boron was imediately added and the alam wasp.
k,%j cleared after six minutes.
Boration was continued until the PPDIL f_ k eyj also cleared, and the power increase was resumed.
The circumstances. at the time of the incident were somewhat
[g unusual in that the operator was faced with control rod insertions to offset an xenon decrease and the PDIL alarm point was increasing with 6017 S
o o
Mr.. John F. O' Leary 2
Docket 50-255 AO-3-73 August 2, 1973 rising power. In this instance, the boration was not done in suffi-cient quantities to overcome the two effects. The limit was exceeded by only 0.1 inch which caused no excessive core power peaking.
l Yours very truly, l
Ralph.B. Sewell (Signed)
RBS/mel Ralph B. Seve11 Nuclear Licensing Administrator CC: BHGrier, USAEC l
I
r -- -
44 ~ "O O
O To:
B. H. Grier FS6EB ACTION CONTROL FORM A.
Action Code F0#191 Name of Licensee and Facility Palisades Docket No. or License No.
50-255 Title Palisades Abnormal Occurrence _- Control Rods Inserted Beyond Limit origin FS&EB Pate Rec'd 10/4/73 B.
FS&EB Branch Coordinator:
Dreher H. D. Thornburg X
Bryan Ellis Paulus C.
Action Requested of:
ADREMP '
M&PPOB EPB RPB ADC0 X
OB CB TAB 00E REGION Date Requested 10/4/73 Completion Requested by 10/19/73 Reference Letter to J. G. Davis From S. E. Bryan dated October 4,1973 D.
Action Requested:
Please take this natter up with Licensing (TR).
E.
Date Action Completed Close-out (Date & Method)
~
Comments:
If completion date is not consistent with your work schedule, please let us know.
Q 'N pv 0
Y he d a o d D. Thornburg, Chief Field Support & Enforcement Branch Directorate of Regulatory Operations