ML20085L941

From kanterella
Jump to navigation Jump to search
AO Bf EAO-418W:on 740218,during Collection of Fish Impinged on Screen,Screen Differential Pressure Increased Suddenly Causing Operator to Omit Fish Count.Temporary Diverter Gate Installed Pending Intake Structure Mod
ML20085L941
Person / Time
Site: Browns Ferry Tennessee Valley Authority icon.png
Issue date: 03/01/1974
From: Gilleland J
TENNESSEE VALLEY AUTHORITY
To: Moseley N
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
AO-BF-EAO-418W, NUDOCS 8311070031
Download: ML20085L941 (2)


Text

.

  • ENNESSEE CHATTANOOGA, VALLEY OHOAITY naq\ ,j TLhFJNESSEE 3740'1 L' :e- \ /r"% G March 1, 1974 h

,md [3hyI f {"' i OF PEOPLG IN

, PARTNF- ASHip Iir. Ucrran C. "oseley, Director Region II Replatorr Operr.tions Office w((b.

k ara KQ%m U.S. Atonic Energy Cc=ission 230 Peachtree Street, '?.

Atlanta, Georgia 30303

Dear Mr. 'Ioseley:

Subject:

TZT!"SCEE VALLEY AUTHORITY - 3907HS IMRY HUCL"El PIKIT U:IIT 1 - DOCI2Z I!O. 50-259 - FACILITY OPERATIHG LICE::GE DPR InITO:IIE"D.L AB'?ORMAL OCCURRZ!CE REFORT BF EAO- hl8'.7 This report provides details concerning failure to meet the veckly fish collection and classification requirements during the week of February 17, 1974. This was reported by telephone to AEC Co::pliance, Region II, on February 22, 197h. "VA does not interpret this occurrence as a reportable incident rcquired by the Brovns Ferry nuclear Plant Tr.vironmental Technical Specifications since no liniting condition for operation was exceeded and no significant environ ental inpact resulted frcn failure to meet the collecting requirement. This report is being filed at the request of Mr. A. Cunninghan of your office,

':"ne environmental technical specificnions require collecting the ..

fish impinged on a selected screen for a 2h -hour period three times a veek. At 9 a.n. on February 18, 197h, a 24-hour test period was started. At approxinately 8:30 p.n. the traveling screen differen-tial suddenly started increasing rapidly which indicated a rapid accunulation of material on the screens. The screen differential pressure increased to approxinately 18 inches of vater within a period of 30 ninutes. "his differential vould nornally be about 2' inches of water with clean screens. To prevent screen danage and possible failure, the operator inmediately started vashinc all six screens without recard to test requirenents for fish collection.

A new test period was begun at 8:30 p.n. and terminated lh hours later at 10:30 a.n. on February 19, 197h, when the biologist was at the plant to count and classi1N/ the fish.

, f 831107003g 74939,

{0RADOCK 05000259

./ r L

(('f {. '~

PDR +

L

,7 mlf'9 <j,. r' ^ .- [ . * *

,F  : f~" t*. - *I h p,.,

'J1 .

n , A;, ,',. , ,7 * , (' Y* ,._

' $. p u..+

.'} [: 1 ( , = '. 7

.y'.  % * ..

[' ,~, d;p;.@C i .,'.[.. %

,. y .'". l'.: fiffT,g.," i,N :' g .

Yhd- . .t 4 . . , Q.",{t. .>rdy .' a, -$ .*g i ,

5 l* W ? } ' % ~l .' . .- l- ;-' b, l $

4' '., ~ - -

'~*-'? -#'

E .,

o o Mr. Hornan C. "cseley March 1,1974 An alnost identical condition occurred at approxinately 11:30 p.n.

on February 19, 197h, resulting in a 10-hour collection which was terminated at 10 a.n. on February 20, 19Th, so the biologist could count and classify the fish. Approximately 24,000 fish were collected during the 14-hour period on February 19, and approxinately 20,000 fish vere collected on February 20 during the 10-hour period. "he reactor was at approximately 50 percent pover.

Periodically, large nunbers of shad ninnovs and/or a large accunula-tion of trash collect suddenly on the screens of the operating pumps.

'Inen this occurs, the screen differential increases very rapidly with a possible result of severe screen damage or failure. The automatic screen vash circuitry had been previously disconnected to allow nanual vashing for the pu pose of estinating fi::h inpincenent. Equiteent design is such that it is not possible to selectively vash individual screens and keep the fish vached from one screen segregated fron the fish vached fren the other screens and yet prevent equip-ent denace during conditions such as described above.

There is no absolute reans available to conpletely clininate a recurrence without nodification to the intake structure. A tenporary diverter cate has been fabricated and installed in the screen vash sluice trench so that fish fron any celected screen nay be diverted into a test bachet either prior or subsequent to vashing the renaining screens. "his vill aid in complying with the requirenent for counting all fish inpinged on a selected screen for a 2h-hour period. Design of a pernanent facility is under way. "'he fish inpinged during the lk- and 10-hour periods vill be revised upward by the ration of 24-to-lh and 2h-to-10, respectively, to correct the count in the nonthly report.

Very truly yours, ,

g bo

/[.b , 4' J. E. Gilleland Rh-Assistant to the "anacer of Power CC: Mr. J. F. O' Leary, Director Directorate of Licensing U.S. Atonic r nercy Connission j Uachington, D.C. 205h5 3,

,