ML17252A226

Letter Submitting Reportable Occurrence Number 050-249/1976-17 in Accordance with Technical Specifications, Section 6.6.B

ML17252A226
Person / Time
Site:	Dresden
Issue date:	09/30/1976
From:	Stephenson B Commonwealth Edison Co
To:	James Keppler NRC/RGN-III
References
BBS Ltr. #76-750
Download: ML17252A226 (3)

Text

. '.. ~ :.

.,fommori'4th Edison.

. :;;.cOresden Nuclear.Power Station.

N*R.R.

0#1 Morris, Illinois 60450 Telephone 815/942-2920

• ~*

BBS Ltr. '#76-702 September 30, 1976*

Mr. James G.. Keppler, Regional Director Directorate of Regulatory Operations - Region III U. S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137 Enclosed please find Reportable Occurrence*report number 50-249/1976-17.

• This report is being'submitted to your office in. accordance with the Dresden

.Nuclear Power Station Technical Specifications~ Section 6.6.B.

BBS:jo ens on Superintendent.

Dres"den Nuclear Power Station

• .;.~Enclosure.

cc:. Director of Inspection &.Enforcement Director of Management Information & Prog_ram Control.

File/NRC

. REGULATORY.DOCKET FILE COPV

. t

LICENSEE EVENT REPORT

:~)"'...

. CONTRO~'.:BLOC1<'\\ '

1.,. I I I J..

.. 'LEASE PRINT ALL REQUIRED INFORMATION)

'I>* _,

UcENSEE LICENSE EVENT NAME

'_LICENSE NUMBER*

TYPE

- TYPE- -

@E] IIILl.Pl'RISl3 I 10101~10101010101-10101 IJ/*11It11111 101 f I 7 - 8 9 -

• 14 15

'25 -- - 26_

.. 30

.31 - 32 REPORT REPORT CATEGORY TYPE -

SOURCE DOCKET NUMBER

@E]coN'T I I I tCJ lbJ IOl5l017IOl~l~f,I EVENT DATE -

REPORT DATE Io I c:t I / I '6 17 I C I _ I 0 I q 131 o 17 I lz.J 69 74 75::-;--

80.

1 -_0 57 58 59<<.. --

60 61 68

___ EVENT DESCRIPTiON 10'21.I AT 1'1l.5 -110URS ON t:tjt'lj7b 1 1)E-IN£RTrNG-OF" THE:"DR'IWEU-WAS-BEGUN IN I 7

8 9 80 10'31 I AA/TtCIPffflOJV OF THE SCH£DULE:D IJNIT SHUTDOWN FOR 1<EFU£).JNG-. AC -I 7 - _ *-0 "9 00

-lo141 lc.o~DtNG-TO SEC-T10N 3.7. A. 5. 'B OF" Tl-4£ T£CHNIGAL..S-PEC1F1c.11.rro/IJS ])Ry-I 7

8 9 BO

____. lol51 !WELL '])£*JN£"R::rtNG-fVIAY CfJ'i>1M£NG£ J.,4 HOURS PRIOR. TO A SHUTl>OWN. I *_

- 7 8 *9 80

~

I Tf-lc. 'D1<.'IW£LL 0'1.VGEN. C:O.iVC.£NTRATION E)(CEEDED.I./ Ofo AT APPROX.I MATELV f 7 -8 9 PRIME (Sfi~ mt!Vni:f).SHe::r)SD -

SYSTEM CAUSE COMPONENT COMPONENT CODE CODE COMPONENT CODE SUFPUEtl MANUFACTUF\\ER VIOlATXlN

- *~. [§0 ISIAI LE.J IZ.IZlZIZIZIZI

-l£j IZt91'1.dqJ _ lYJ

-. - 7 8 9 *10 --

11 12 17 -

43 44 47 : -

48

~ALISE DESCRiP,Tl0N

~~I 1w ORDER io sltirsFy fYJ1N1muWJ, SY.sritM J...iYAD 'R.£QUtR£r1rc-N{S. UN1T~3 I.-

1 8 9 y

80 --

. lol9Ll'w1ts *wor-*** SHUT' TJOWJJ WITHIN 14./-£:0..if,~ HOUR'- P.f1<10D-suBs-~Qui:NT To J)RYWEl.. L J: -

. 7. 8 9 80 -

-.. /.[!:@*l*UE~.aNERTl.N.G-~.. SPtf"E'TY,.l.~Pl-ICA.TlotJS

.. ~,,WE;R£,.-}';J.04:::,ffiORE:E;$f.G:N;f:E:JGAN'T~::.m.:HAN.~~-JF:,... J -

.>.. ',:'<~.;..-,Q.. 9.

<METH*O--D-OF-(Sef; A-rtAC.!t£D*SHcutf) BO_*

• -.-. FACILITY

.. -._ STATUS

"' POWER OTHER STATUS

'DISCOVER';:

DISCOVERY DESCRIPT:ON

[ill]

(QJ Io 17 I 3 I I Nit I lAJ

-1.._ __

_._M

......... fl...__. __

-_ -~..----.....-11 1 e s

10 12 13 44 45*

46

-FORM-OF ACTIVITY cmlTENT 11:l:l -Rilz.sr~-: OF izf-~Er* _

_AMOUNT °JJ~CTIVITY,,.., 1

___ 1

-NALOCATION OF RELEASE 1

1 -- a *,~ --**

10 1-1 -----~._,...,.,,,;::,...._: --44 -- *** 4~5_..,......---.--...........,..-....,....,............. __ __,_.;.,,.--___

---'00

• 80 PERSONNEL.E)(POSURES

- -NUMBER -

TYPE 0El3CRIP.TION

(!21 :j'OlD.10 I...'l6J I NA I

_ 1 _ e s 11 12 13 80 -

. PERS.ONNEL INJURIES NUMBER DESCRIPTION ff8 IOI OIOll

~ _-___

M_'A __

...,...__~ __

__,I 1

e s 11 12 00

_ OFFSJTE CONSEQUENCES Elfil

-Al 11 -

. 7 - 89 80 -

LOSS 'O_R DAMAGE TO FACILITY

• TYPE

• DESCRIPTION Efil *IZ.J -.

NI/

1 0* s -

10 -

80

.PUBLiciTY

-./-

(ill]

NA 7

8 9 80 ADDITIONAL FACTORS

fl.~... ~,

~

EVENT DESCRIPT!ON (Continued) 2030 hour0.0235 days <br />0.564 hours <br />0.00336 weeks <br />7.72415e-4 months <br />s~ At 0200 hours0.00231 days <br />0.0556 hours <br />3.306878e-4 weeks <br />7.61e-5 months <br /> on 9-19-76, the unit load drop was halted at the direction of the Chicago load dispatcher because of a system emergency.

.* Dr)'Weil. inerting *was begun at 0415 hours0.0048 days <br />0.115 hours <br />6.861772e-4 weeks <br />1.579075e-4 months <br />; *by 0600,- the dr-iwell oxygen con- *

• centrad.on had d:ropped below 4%.

A similar event occurred on Unit-2 in

.J:une, 1975.

(50-249/1976-17)

CAUSE DESCRIPTION (Continued) the unit.had been actually shut down, since the drywell oxygen concentration exceeded 4%

for.~ less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

As stated above, an acceptable drywell oxygen concentration was achieved by 0600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br /> on 9-19-76.

No further action was considered appropriate.

b*..