ML20126M499

Notifies That IE Bulletin 81-03, Flow Blockage of Cooling Water to Safety Sys Components by Corbicula Sp (Asiatic Clam) & Mytilus Sp (Mussel), Has Been Sent to Listed Utils

ML20126M499
Person / Time
Site:	Wolf Creek, Cooper, Arkansas Nuclear, River Bend, Waterford, South Texas, Comanche Peak, Fort Calhoun, Fort Saint Vrain
Issue date:	04/21/1981
From:	Madsen G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
IEB-81-3, NUDOCS 8106190003
Download: ML20126M499 (1)

Text

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• MEMORANDUM FOR: Those Listed Below FRCM: G. L. Madsen, Chief, Reactor Projects Branch, IE:RIV

SUBJECT:

IE BULLETIN NO. 81-03 Subj.ect IE Bulletin has been sent to the following listed licensees. A copy of the IE Bulletin is attached for your information.

Arkansas Power & Light Company Gulf States Utilities ANO-1 & 2 (50-313; 50-368) River Bend (50 458; 50-459)

Nebraska Public Power District Houston Lighting & Power Company Cooper Nuclear Station (50-298) South Texas (50-498; 50-499)

Omaha Public Power District Kansas Gas & Electric Company Fort Calhoun (50-285) Wolf Creek (STN 50-482)

Public Service Company of Colorado Louisiana Power & Light Company Fort St. Vrain (50-267) Waterford-3 (50-382)

Texas Utilities Generating Company Comanche Peak (50-445; 50-446)

,(/$ '5EW G. L. Madsen, Chief Reactor Projects Branch ATTACHMENT:

As stated DISTRIBUTION:

IE/DMS MPA/LOEB 1 l

IE/RPRIB l IE/ REB IE/SRSI IE/EP ADM/CMB l

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810 6 7 0 c ooS 4

IES 81-03 Acril 10, 1981 Page 2 of 5

~1cw c:tes measured during surveillance tasting througn the CCUs at ANO-2 nad deteriorated over a numcer of months. Flushing aftar plant snutdown initially resultad in a further reduction in flow. Procer flow ratas were restored only after the clam cecris hac been removed manually from tne CCUs.

The examination of the Unit 1 service water system revealed that tne "C" and "0" emntainment coolers were clogged by clams. Clams were found in the 3-inen inlet headers and in tne inlet water boxes. However, no : lams were found in the "A" and "B" coolers. This fouling was not discovered curing surveillanca testing because there was no flow instrumentation on tnese ::alers.

The service water system in Unit I was not fouled otner nan stateo acove, and the licensee attributac this to the fact that the service water pumo suctions are located benind One main concensar circulating pumcs in tne intake structure.

!t was nougnt that silt and clams entering the intake cays would be sweet througn the condenser Oy the main circulating pumos and would not accumulata ,

in the back of the intake bays. In contrast, Unit 2 has no main circulating pumos in its intake structure because ::ndenser neat is rejected througn a cooling ::wer via a closed cooling system. As a result of lower flowrates of water nrougn the Unit 2 intake structure, sil and clams could have a tendency to accumulate more racidly in Unit 2 than in Unit 1. During the sectemcer outage, clams and snells were found to have accumulatec to deptns of 3 to 4-1/2 feet in certain areas of the intake bays for Unit 2.

The Asiatic clam was first found in the United States in 1938 in the Columcia River near Knappten, Wasnington. Since then, Corcicula sp. has scread across the country and is now reported in at least 33 statas. The Tennessee Valley Autnority (TVA) pcwer plants also have experiencea fculing caused by these clams. They were first found in the condensers and service water systems at the Shawnee Staam Plant in 1957. Asiatic clams were later found in :ne Browns Ferry Nuclear Plant in Octocer 1974 only a few montns after it went into oceration. This initial clam infestation at Browns Ferry was ennanced oy the fact that, during the final stages of construction, tne cooling water systems were allowed to remain filled with water for long perices of time wnile the systems were not in u:le. This condition was :enducive to the growth and accumulation of : lams. Since that time, tne Asiatic clam has scread across the Tennessee Valley region and is f0und at virtually all the TVA steam-electric and hydroelectric generating stations.

Present centrol procacures for Asiatic clams vary from station to station and in their degree of effectiveness. The use of snock calorination during ' surveil-lance' tasting as the only method of 00ntrolling oiofouling by nis organism accears : ce ineffective. The level of fouling has been recuced to accectacle levels at T/A stations by using continuous enicrination :uring :eak scawning cericcs, clam traps, and mechanical cleaning curing station outages.

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i IE3 81-03 Aoril 10, 1981 i Page 3 of 6 The results of a series of tests on mollusks performed at the Savannah River facility showed that mature Coroicula sp. had as much as a 10 percent survival rate after being exposed to nign concentrations.of free residual enlorine (10 to 30 pom) for up to 54 hours6.25e-4 days <br />0.015 hours <br />8.928571e-5 weeks <br />2.0547e-5 months <br />. When the clams were allowed to remain buriec

. in a couple of inches of mud, their survival rates were as nign as 55 percent.

In studies on 'snelled larvae, acproximately 200 microns .in si:e, TVA reported preliminary results indicating that a total chlorine residual of 0.03 to 0.30 pom for 96 to 108 hours0.00125 days <br />0.03 hours <br />1.785714e-4 weeks <br />4.1094e-5 months <br /> would be required to acnieve 100 percent control of

'the Asiatic calm larvae.

Corbicula sp. has also shown an amazing ability to survive even wnen removed from tne water. Average times.to death when left in the air have been recorted for low relative humicity as 6.7 days at 30*C (86*F) and 13.9 days at' 20 C (58*F) and for hign relative humidity as 3.3 days at 30*C and 25.3 days at 20*C.

Coroicula sp. on the other hand, has sncwn a much greater sensitivity to heat.

Tests performed by TVA resulted in 100 percent mortality of clam larvae, very young clams, and 2mm clams when they were exposed to 37 C (117*F) water for 2 minutes. Mature clams, up to 14mm, were also tested and all died at 47*C following a 2 minute exposure. A statistical analysis of the 2 minute exposure test data revealec that a temperature of 49*C (120*F) was necessary to reacn the 99 percent confidence level of mortality for clams of the si:e tested.

To date, heat has been shown to be the most effective way of producing 100 percent mortality for the Asiatic clam. At ANO, the service water system was flushed with 77*C (170*F) water obtained from the auxiliary boiler for accrox-imately one half hour; 100 percent mortality was excected.

A similar proolem has occurred with mussels (Mytilus sp.). Infestations of mussels have caused flow blockage of cooling water to safety-relatec ecuiement at nuclear plants such as Pilgrim and Millstone. Unlike the Asiatic clam, mussels cause biofouling in salt water cooling systems.

The event at ANO is ;ignificant to reactor safety because (1) the fouling represented an actual common cause failure, i.e, inacility of safety system reduncant comconents to perform their intanced safety functions, anc (2) the licensee was not aware that safety system comconents were fouled Althougn the fouling at ANO-2 developed over a numoer of months, neither the licensee management control system nor periodic maintenance or surveillance program cetected the f ailure.

ACTICNS TO BE TAKEN 3Y LICENSEE 5 Holders of Operating Licenses:

1. Determine wnether Coroicula sp. or Mytilus so. is cresent in :ne vicinity of the station (local environment) in e1:ner the source or receiving water body. If the results of current field monitoring programs orovide reason-acle evidence that neitner of these species is cresent in :ne local environment, no furtner action is necessary excect for items 4 and 5 in tnis section for holders of ocereting licenses.

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. i IES 31-03 Aoril 10, 1981 Page a of 5 l

2. If it is unknown whether either of these species is present in the local environment or. is confirmed that either is present, determine wnether fire protection or safety-related systems that directly circulate water

-from:the station source or receiving water cody are fouled by clams or mussels or decris consisting of their snells. An acceptacle nethod of confirming the absence of organisms or'snell debris consists of opening and visually examining a representative sample of comoonents in potentially affected safety systems and a samole of locations in potentially affected fire protection systems. The samole shall have included a distribution of comoonents with sucoly and return piping of various diameters wnich exist in the potentially affected systems. This inspection snall have oeen conducted since the last clam or mussel soawning season or within

.the nine month period preceding the cate of this bulletin. If the aosence

.of organisms or shell debris has been confirmed by such an inspection or another method whicn the licensee shall describe in the resconse (suoject to NRC evaluation and acceptance), no further action is necessary excect  :

for items 4 and 5 of actions acolicaole to holders of an coersting license.

3. If ' clams, mussels or shells were found in potentially affected systems or their aosence was not confirmed by action in item 2 acove, measure the flow rates through individual comconents in potentially affected systems to confirm adecuate flow rates i.e. , flow blockage or degradation to an unacceptably low flow rate has not occurred. To be acceptable for this determination, these measurements shall have been made within six months of the date of this bulletin using calibrated flow instruments. Di f f er-ential pressure (DP) measurements between supply and return lines for an individual component and OP or . flow measurements for parallel connectec individual coolers or components are not acceptable if flow blockage or degradation could cause the observed 09 or be masked in parallel flow patns.

Other methods may be used which give conclusive evidence tnat flow blockage or degradation to unacceptably low flow rates has not occurred. If another method is used, the basis of its acceptance for this determination shall I be included in the response to this bulletin.

If the above flow rates cannot be measured or indicate significant flow degradation, potentially affected systems shall be inspected according to item 2 aoove or by an acceptacle alternative method and cleaned as necessary.

This action shall be taken within the time period prescribed for suomittal of the report to NRC.

a. Describe methods either in use or planned (including implementation date) for preventing and detecting future flow blockage or degradation due to clams or mussels or shell decris. Include the following information in this description:

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IES S1-03 Acril 10, 1981 Page 5 of 6

a. . Evaluation of the-potential for intrusion of the organisms into these systems due to low water level and high velocities in the intake structure expectad during worst case concitions.

c. Evaluation of effectiveness of prevention and detaction methods used in the past or present or planned .for future use.

5. Describe the actions taken in items l'through 3 toove and include the ,

following information:

a. Acolicaole porteions of the environmental monitoring program including last samole data and results.

b. Comconents and systams affected.

c. Extent of fouling if any existec.

d. How and when fouling was discovered.

e. Corrective and preventive actions.

Holders of Construction Permits:

1. Detarmine whether Corbicula sp. or Mytilus sp. i s present in the vicinity of the station by completing items 1 anc 4 acove that apply to coerating licenses (OL).

2. If these organisms are present in the local environment and potentially ,

affected systems have been filled from the station source or receiving water body, determine whether infestation has occurred.

3. Describe the actions taken in items 1 and 2 above for construction permit holders and include the following information:

a. Acolicaole portions of the environmental monitoring program including last samole date and results.

b. Comoonents and systems affected.

c. Extent of fouling if any existed,

d. How and wnen fouling was discovered.

e. Corrective and preventive actions.

Licensees of facilities with ocerating licenses snall provide the requested recort witnin 15 days of the cate of nis bulletin. Licensees of facilities with construction permits snall provice the report witnin 90 days. .

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l IE3 81-03 Page 5 of 5 Acril 10, 1981 Provide written reports as required above, signed uncer oath or affirmation, under the provisions of Section 132a of the Atomic Energy Act of 1954 Recorts

.shall be sucmitted to the Director of the acprocriate Regional Of fice and a cocy forwarded to the Director, Office of Inspection and Enforcement, NRC, Washington, O.C. 20555.

This request for information was approved by GA0 under a clanket clearance numcer R0072 wnich expires Novemcer 30, 1983. Comments on burden and dupli-cation should be directed to Office of Management anc Budget, Room 3201, New Executive Office Building, Washington, D.C. 20503.

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IE Sulletin No. 81-03, Acril 10,1981 RECENTLY ISSUED IE BULLETINS Bulletin Suoject Data Issued Issued To No.

30-23 Failures of Solenoid 11/14/80 All power reactor facilities Valves Manufactured by witn Operating Licente (CL)

Valcor Engineering or Construction Permit (CP)

Corporation 80-24 ?revention of Damage 11/21/80 All cower reactor facilities Oue to Water Leakage ith Goerating License (OL)

Inside Containment or Construction Permit (CP)

(Octocer 17, 1980 Indian Point 2 Event)

Suo. 4 Failure of Control Reds 12/13/80 To specified SWRs with Sulletin to Insert During A Scram an Ocerating License (OL)

~

30-17 at a BWR and All BWRs nith a Construction Permit (CP) 80-25 Operating Proolems with 12/19/80 All BWR facilities with Target Rock Safety-Relief Operating License (OL)

Valves at SWRs and specified near term Operating License (OL)

BWR facilities and all BWRs with a Construction Permit (CP) 81-01 Surveillance of 1/27/81 All power reactor Meenanical Snuceers facilities with an Operating License (OL) and to specified f acili*ies with Construction Permit (CP) 30-17, Failure to Control Rods 2/13/81 All BWR f acilities Suo. 5 to Insert During a Scram with Coerating License (OL) or Construction Permit (CP) 81-01' Surveillance of Mechanical 3/4/81 All power reactor facilities Rev. 1 Snuceers witn an Operating License (CL) 1 and specified f acilities witn j a Construction Permit (CP) i 81-02 Failure of Gate Type Valves 3/9/81 All power reactor faclities to Close Against Differential with an Operating License (0L)

Pressure or Construction Permit (CP)

Enclosure l

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MEMORANDUM FOR: Those Listed Below FROM: G. L. Madsen, Chief, Reactor Projects Branch, IE:RIV

SUBJECT:

IE BULLETIN N0. 81-03 Subject IE Bulletin has been sent to the follcuing listed licensees. A copy of the IE Bulletin is attached for your infonnation.

Arkansas Power & Light Company Gulf States Utilities ANO-1 & 2 (50-313; 50-368) River Bend (50-458; 50 459)

Nebraska Public Power District douston Lighting & Power Company South Texas (50-498; 50-499)

CooperNuclearStation(50-298)

Omaha Public Power District Kansas Gas & Electric Company Fort Calhoun (50-285) Wolf Creek (STN 50 482)

Public Service Company of Colorado Louisiana Power & Light Company Fort St. Vrain (50-267) Waterford-3(50-382)

Texas Utilities Generating Company Comanche Peak (50-445; 50-446)

8.$ 7/ud W G. L. Madsen, Chief Reactor Projects Branch ATTACHMENT

As s+ated DISTRIBUTION:

IE/DMS MPA/LOEB IE/RPRIB IE/ REB IE/SRSI IE/EP ADM/CMB l

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SSINS No.: 5820 Accession No.:

3011040239 IE3 81-03 1

UNITED STAics ,

NUCLEAR REGULATORY CCMMI53 ION I 0F ICE OF INSPECTION AND ENFORCEMENT l WASHINGTCN, D.C. 20555 '

l IE Bulletin No. 31-03 April 10, 198' 1 Page 1 of 5

' FLOW BLOCKAGE OF COOLING WATER TO SAFETY SYSTEM CCMPONENT5 BY CORBICULA SP. (ASIATIC CLAM) AND MYTILUS SP. (MUSSEL)

Descriotion of Circumstances:

On Septemoer 3, 1980, Arkansas Nuclear One (ANO), Unit 2, was snut down after the NRC Resident Insoector discovered that Unit 2 nad failed to meet the Tecnnical Scecification recuirements for minimum service water flow rate througn the containment cooling units (CdUs7.' After p Fant snutdown, Artansas Power and Lignt C0moany, the licensee, determined that the inadequate flow was due to extensive plugging of the CCUs by Asiatic clams (Corbicula species, a non-native fresh water bivalve mollusk). The licensee disassemETed tne service water piping at the coolers. Clams were found in the 3-inch diameter supoly pioing at the inlet to the CCUs and in the cooler inlet water boxes. Some of the clams found were alive, but most of the decris consistec of snells. The size of the clams varied from the larvae stage uo to one inch. The service water, which is taken from the Dardanelle Reservoir, is filtered cefore it is pumped through the system. The strainers on the service water pump discharges were examined and found to be intact. Since these strainers have a 3/16-inen mesh, much smaller than some of the shells found, it accears that clams had been growing in the system.

Following the ' discovery of Asiatic clams in the containment coolers of Unit 2, the licensee examined other ecuipment cooled by service water in both Units 1 and 2. Inscection of otner heat exchangers in tne Unit 2 service water system revealed some fouling or olugging of additional coolers (seal water coolers for both recundant containment soray pumos ano one low pressure safety injec-tion pumo) due to a builduo of silt, corrosion products, and decris (mostly clam shell pieces). The nigh-pressure safety injection (HPSI) pumo bearing and seal coolers were found to have suostantial plugging in the 1/2-inch pipe service water sucoly lines. The plugging resulted from an accumulation of silt and corrosion produc s.

Clam snells were found in some auxiliary building room coolers and -in the auxiliary cooling water system wnich, serves non-safety-related ecuipment.

IE3 81-03 April 10, 1981 Page 2 of 5 Flow ratas measured during surveillance testing througn the CCus at ANO-2 hac deteriorated over a numoer of months. Flushing after plant shutdown initially resulted in a further reduction in flow. Procer flow rates were restored only after the clam decris had been removed manually from the CCUs.

The examination of the Unit 1 service water system revealed that the "C" and

'"0" containment coolers were clogged by clams. Clams were found in the 3-inch inlet headers and in the inlet water boxes. However, no clams were found in the " A" and "B" coolers. This fouling was not discovered during surveillance tasting because there was no flow instrumentation on :nese coolers.

The. service water system in. Unit 1 was not fouled other than statec above, and the licensee attributed this to the fact that the service water pumo suctions are located benind the main condenser circulating pumos in the intake structure.

.!t was thought that silt and clams entering the intake cays would be swept througn the condenser by tne main circulating pumos and would not accumulata in tne back of the intake bays. In contrast, Unit 2 nas no main circulating pumps in its intake structure because condenser heat is rejected througn a cooling tower via a closed cooling system. As a result of lower flowrates of water througn She Unit 2 intake structure, silt and clams could have a tandency to accumulate iture raoidly in Unit 2 tnan in Unit 1. During the Sectemoer outage, clams and shells were found to nave accumulated to cepths of 3 to 4-1/2 feet in certain areas of the intake bays for Unit 2.

The Asiatic clam was first found in the Unitad States in 1938 in the Columoia River near Knapoton, Wasnington. Since then, Corbicula sp. has spread across the country and is now reported in at least 33 states. The Tennessee Valley Authority-(TVA) power plants also have experienced fouling caused by these clams. They were first found in the condensers and service water systems at the Shawnee Steam Plant in 1957. Asiatic clams were later found in the Browns l Ferry Nuclear Plant in Octocer 1974 only a few months after it went into ,

operation. This initial clam infestation at Browns Ferry was ennanced oy tne fact that, during the final stages of construction, tne cooling water systems were allowed to remain filled with water for long periods of time wnile the

. systems were not in use. This condition was conducive to the growth anc f

-accumulation of clams. Since that time, tne Asiatic clam has scread across the Tennessee Valley region and is found at virtually all the TVA steam-electric and hydroelectric generating stations.

Present control procedures for Asiatic clams vary from station to station and in their cegree of effectiveness. The use of snock cnlorination curing surveil-lance testing as the only method of controlling biofouling by this organism accears to te ineffective. The level of fouling has teen recuced to acceptacle levels at TVA stations by using continuous enlarination during peak soawning periccs, clam traes, and mechanical cleaning curing station outages.

IES S1-03 Acril 10, 1981 Page 3 of 5 The= results of ,a series of tests on mollusks performed at the Savannah River

. facility showed that mature Corbicula sp. had as mucn as a 10 percent survival rate after being excosed to n1gn concentrations of free residual chlorine (10 to 40 pom) for up to 54 hours6.25e-4 days <br />0.015 hours <br />8.928571e-5 weeks <br />2.0547e-5 months <br />. When the clams were allowed to remain buriec in a couole of incnes of mud, their survival rates were as hign as 55 percent.

In studies on shelled larvae, approximately 200 microns in si:e, TVA reported preliminary results indicating that a total chlorine residual of 0.03 to 0.40 ppm for 96 to 108 hours0.00125 days <br />0.03 hours <br />1.785714e-4 weeks <br />4.1094e-5 months <br /> would be required.to achieve 100 :ercent control of the Asiatic' calm larvae.

Cordicula so. has also shown an amazing ability to survive even when removed from ene_ water. Average times to death wnen left in the air have been recortec

.for low relative humidity as 5.7 days at 30 C (36*F) and 13.9 cays at 20*C (58*F) and for hign relative humidity sas 3.3 days at 30*C and 25.3 days at 20*C.

Coroicula sp. on the other hand, has snown a much greater sensitivity to neat.

Tests performed by TVA resulted in 100 percent mortality of clam larvae, very young clams, and 2mm clams wnen they were exoosed to 47 C (117*F) water for 2 minutes. Mature clams, uo to lamm, were also tested and all died at 47'C following a 2 minute exposure. A statistical analysis of the 2 minute exposure test data revealed that a tamperature of 49*C (120*F) was necessary to reacn the 99 percent confidence level of mortality for clams of the si:e tested.

To date, heat has been shown to be the most effective way of producing 100 percent mortality for tne Asiatic clam. At ANO, the service water system was flushed with 77*C (170*F) water cotained from tne auxiliary boiler for approx-imately one half hour; 100 percent mortality was expected.

A similar problem has occurred with mussels (Mytilus sp.). Infestations of mussels have caused flow blockage of cooling water to safety-relatec equipment at nuclear plants such as Pilgrim and Millstone. Unlike the Asiatic clam, mussels cause biofouling in salt water cooling systems.

The event at ANO is significant to reactor safety because (1) the fouling recresented an actual common cause failure, i.e, inacility of safety system recuncant comoonents to perform their intended safety functions, and (2) One licensee was not aware that safety system components were fouled Althougn the fouling at 4NO-2 developed over a numoer of montns, neitner the licensee management control systam nor periodic maintenance or surveillance program detected the failure.

ACTICNS T[ 3E TAKEN 3Y LICENSEES Holders of Operating Licenses:

1. Determine wnether Coroicula so. or Mytilus so. is present in tne vicinity of tne station (local environment) in eitner the source or receiving nater body. If tne results of current field monitoring programs orovide reason-aole evicence that neither of nese species is cresent in the local environment, no furtner action is necessary exceat for items 4 anc 5 in this section for hoicers of operating licenses.

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l IES 31-03 l Acril 10, 1981 l Page A of 5 l

2. If it is unknown whetner either of these species is present in the local environment or is confirmed that either is cresent, determine wnether fire protection or safety-related systems that directly circulate water from the station source or receiving water body are fouled :y clams or mussels or deoris consisting of their snells. An accectacle method of confirming the absence of organisms or shell decris consists of coening and visually examining a representative sample of comoonents in potentially affected safety systams and a samole of locations in potentially affected fire protection systems. The samole shall have included a cistribution of components with sucoly and return piping of various diameters wnica exist in the potentially affected systems. This insoection snall have been conducted since the last clam or mussel spawning season or within the nine month period prececing the cate of tnis bulletin. If tne aosence of organisms cr shell decris has been confirmed by such an insoection or another method which the licensee snali describe in the resconse (suoject to NRC evaluation and acceotance), no further action is necessary exceot for items 4 and 5 of actions acclicacle to hoicers of an acerating license.

3. If ' clams, mussels or shells were found in potentially affectac systems or their aosence was not confirmed oy action in item 2 acove, measure the flow rates through individual comconents in potentially affectec systems to confirm adequate flow rates i.e. , flow blockage or degradation to an unacceptacly low flow rate has not occurred. To be acceotaole for this determination, these measurements snall have been made within six months of the cate of this bulle*.in using calicrated flow instruments. Di f f e r-ential crassure (DP) measurements between suoply and return lines for an individual comoonent and OP or flow measurements for parallel connected individual coolers or components are not acceptacle if flow blockage or degradation could cause the observed DP or ce masked in parallel flow paths.

Other methods may be used which give conclusive evidence tnat flow blockage or degradation to unacceptably low flow rates nas not Occurred. If anotner method is used, the basis of its acceotance for this determination shall be included in the response to this bulletin.

If the acove flow rates cannot be measured or incicate significant flow degracation, potentially affected systems snall be inspectec accorcing to item 2 acove or by an acceptable alternative metnod and cleaned as necessary.

This action snall be taken witnin tne time period prescribed for suomittal of the reoort to NRC.

4 Describe metnods either in use or plannec (inclucing imolementation date) for preventing and cetecting future flow blockage or degracation due to clams or mussels or shell decris. Include the following information in this description:

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IES 31-03 Aoril 10, 1981 Page 5 of 6

a. Evaluation of the potential for intrusion of the organisms into these . systems due to low water level and hign velocities in the intake structure expected during worst case concitions,

b. Evaluation of effectiveness of prevention and detection methods used in the past or present or planned for future use.

5. Describe tne actions taken in items 1 througn 3 acove and incluce the following information:

a. Aoplicaele porteions of the environmental monitoring crogram including last samole date and results,

b. Comconents and systems affected.

c. Extent of fouling if any existed.

d. How and wncn fouling was discovered.

e. Corrective and preventive actions.

Holders of Construction Permits:

1. Determine wnether Corbicula sp. or Mytilus so. is present in the vicinity of the station by comoleting items 1 anc A aoove that apply to coerating licenses (OL).

2. If these organisms are present in the local environment anc potentially affected systems have been filled from the station source or receiving water body, determine whether infestation has occurred.

3. Describe the actions taken in items 1 and 2 above for construction permit nolders and include the following information:

a. Aoplicaole portions of the environmental monitoring program including  ;

last samole data and results. l l

c. Comoonents and systems affectac.

c. Extent of fouling if any existed,

d. How and unen fouling was discovered. ,

e. Corrective and preventive actions.  :

1 Licensees of f acilities with ooerating licenses snali provide the requested I recort within a5 cays of tne : ate of this culletin. Licensees of facilities I with :onstruction permits shall provice the report witnin 90 cays.

,,, y, .._~.7. , . . . . , . , . ,..r,.- ..y, . , - . . . . , _ . . ,. . _ , _ . . . , . , - _ _ , ._ . . _ . , _ . . - - - . . _ . . . . . _ . , _ . . . _.

IE3 81-03 Page 5 of 5 Acril 10,1981 Provide written reports as required above, signed under oath or affirmation, under the provisions of Section 182a of the Atomic Energy Act of 1954 Recorts shall be submitted to the Director of the approcriate Regional Office anc a copy forwarded to the Director, Office of Inspection and Enforcement, NRC, Washington, 0.C. 20555.

This request for information was aoproved by GA0 under a clanket clearance numcer R0072 *nich expires November 30, 1983. Comments on burden and duali-cation should be directed to Office of Management and Bucget, Room 3201, New Executive Office Building, Washington, D.C. 20503.

m - @< _ _ , > - 4.m2 e t IE Sulletin No. 31-03, April 10,1981 RECENTLY ISSUED IE SULLETINS Bulletin Suoject Date Issued Issued To No.

80-23 Failures of Solenoid 11/14/80 All power reactor facilities Valves Manufactured oy witn Operating License (OL)

Valcor Engineering or Construction Permit (CP)

Corporation 30-24 Prevention of' Damage -11/21/80 All power reactor facilities Due to Water Leakage with Goerating License (OL)

Inside Containment or Construction ?ermit (CP)

(Octooer 17, 1980 Indian Point 2 Event)

Suo. 4 Failure of Control Rods 12/18/80 To soecified SWRs with Sulletin to Insert Ouring A Scram an Operating License (OL) 80-17 at'a SWR anc All BWRs with a Construction Permit (CP) 80-25 Operating Proolems with 12/19/80 All BWR facilities with Target Rock Safety-Relief Ocerating License (OL)

Valves at SWRs and specified near term Operating License (OL)

BWR facilities and all SWRs with a Construction Permit (CP) 81-01 Surveillance of 1/27/81 All power reactor Mechanical Snuceers facilities with an Operating License (OL) 1 and to specified f acilities with Construction Permit (CP) 30-17, Failure to Control Rods 2/13/81 All SWR facilities Suo. 5 to Insert Ouring a Scram with Goerating License (0L) or Construction Permit (CP) 31-01 Surveillance of Mechanical 3/4/31 All power reactor facilities Rev. 1 Snuceers with an Coerating License (OL) ano specified f acilities witn a Construction Permit (CP) 81-02 Failure of Gate Type Valves 3/9/81 All power reactor facif ties to Close Against Differential with an Coerating License (OL)

Pressure or Construction Permit (CP)

Enclosure

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