ML20086T991

Noncompliance Notification:On 911219,approx 400 Diving Ducks Collected in Circulating Water Sys Screenwash Baskets.Caused by Abundant Food Supply Provided by Circulating Water Discharge.Flow Rates Reduced

ML20086T991
Person / Time
Site:	Cook
Issue date:	01/03/1992
From:	Fitzpatrick E INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
AEP:NRC:1171, NUDOCS 9201070147
Download: ML20086T991 (4)

Text

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. e inabana Methican

, Powet Company P 0. Box 16631

,a Columbut OH 43?16 Y

add DNDIANA MKH0GAN POWER AEP:NRC:1171 Donald C. Cook Nucicar Plant Units 1 and 2 Docket Nos. 50 315 and 50 316 License Nos. DPR 58 and DPR 74 UNUSUAL OR IMPORTANT ENVIRONMENTAL EVENT -

APPROXIMATELY 400 DIVING DUCKS COLLECTED IN Tile CIRCULATING VATER SYSTEM SCREENVASil BASKETS U. S. Nuclear Regulatory Comrnission Attn Document Control Desk Washington, D. C. 20555 Janusry 3, 1992 Centlemen:

'he purpose of this report is to inform you that as of vecember 19, 1991 approximately 400 divio6 ducks (lesser and greater seaups) were collected in the circulating water system screenwash baskats at Cook Nuclear Plant. This event constitutes an " Unusual or Important Environmental Event" per Cook Nuclear Plant Technical Specifications (T/Ss) Appendix B, Paragraphs 4.1 and 5.4.2. As such, a verbal notification was made to Nuclear Regulatory Commission (NRC)

Resident Inspector, David Passchi, and to the Michigan Department of Natural Resources (MDNR) on December 5, 1991. In addition, Cook Nuclear Plant T/Ss stipulate that a written report to the NRC is due within 30 days of occurrence. As such, we are rubmitting the attached report.

This document has been prepared following Corporate procedures that incorporate a reasonable set of controls to ensure its accuracy and completeness prior to signature of the undersigned.

Sincerely, V

E. E. Fitzpatrick Vice President tjw Attachment ll i Y's 1 you l ll1%'@$$hp

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,4 Document Control Desk 2 AEP:NRC:1171 cc: D. II, W1111atos, J r.

A. A. Blind Bridgman .

I A. B. Davis, Region III P. A. Barrett  ;

B. F. llenderson l R. F. Kroeger B. Walters Ft. Wayne i NRC Realdent Inspector T. Colburn NRC J. G. Keppler J. R. Padget.t G. Charnoff D. llahn -

ANI Library INPO B. A. Svensson l

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L Attachment 1 to AEp:NRC:1171 Page 1 Retsort of Unusual or Iwoorrant Environrtental Event f Conditions Prior to Occurrence {

Unit 1 and 2 in Mode 1 (Power Operation) at 100% power.

Description of Event, On December 5, 1991, it was noted that approximately 90 to 100 dead i lesser and Breater seaups (diving ducks) had been collected in the screenhouse fisn baskets (EIIS/NN.SCN), It was found that a zebra ,

mussel population, which provided an abundant food supply for the ,

ducks, had been established on the circulating water intake structures l and surrounding rip rap. The ducks became caught up in the intake 1 water flow while diving to feed on the zebra mussels.

Cause of Event The - event was caused by the abundant food supply and warm water environment provided by the circulating water discharge. As ducks dove down to feed on the zebra mussels, they became caught up in the circulating water intake flow. The presence of zebra mussels in the  :

digestive tract of the ducks was verified by dissection, It should be noted that this is the first occurrence of this type and is related to the fact that the past summer was the first season of major zebra mussel infestation.

n factor contributing to the event was the closure of the circulating  ?

water intake shutoff valve (124'MO 30) for repair work. This reduced the circulating water intake pathway from three sixteen foot intake pipes to twa sixteen foot pipes, resulting in an increase in the ilow velocity from the other two intake pipes, ,

Analysis of Event This event is considered reportable pursuant to Technical Specifict. tion Appendix ' B, paragraphs 4.1 and 5.4.2 as an unusual or important environmental event which indicates or could result in a significant environmental impact related to plant operation.

In response to the event, one of the Nuclear Regulatory Commission's resident inspectors at Cook Nuclear Plant, David Passchl, was verbally notified on December 5, 1991, Other agencies notified include the Michigan Department of Natural Resources (MDNR), and the US Department '

of Fish and Wildlife (DW). Both the MDNR and the DW responded to the site to retrieve duck remains for research purposes. In addition, the DW evaluated the site for a possible observation station.

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Attachment 1 to AEp:NRC: 1171 Page 2 In the summer months, the combined numbers of lesser and greater seaups form a population larger than any other species of duck in North America, with the exception of the mallard. Trank C. Bellrose states in his book Ducks. Geese and Swans of North America that the average population of the scaups is about 7.415,000. The total number of ducks recovered from the screenhouse fish baskets was 400, representing 0.00545% of the total seaup population. Consequently, the effect of this event on the scaup population has been negligible.

Corrective Action Several interim actions have been taken to discourage ducks from populating the area. These measures include chasing the ducks with a boat, firing blank shells at the ducks, and locating rafts and predator eye balloons at the circulating water intake structures. In addition, to reduce flow rates at the intake structuro screens, circulating water pump #21 was removed from service on December 9,1991 and 12 WO 30 was returned to its full / open position on December 13, 1991.

Since these measures have been taken, a dramatic decrease has been noted '. n duck impingement. No ducks have been- found in the fish

. baskets since 12/15/91 As a more permanent solution to prevent recurrence, the intake structures will be thoroughly hydrolazed during the 1992 refueling outages to remove the zebra mussels. This should prevent the ducks from accumulating at the intake structures. The effectiveness of ~

hydrolazing the intake structures will be evaluated to determine whether it is necessary to take additional measures to prevent recurrence of this problem.

Failed Component Identification None.

Previous Similar Events None.

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