United States Nuclear Regulatory Commission - Protecting People and the Environment

Service Water System Problems Affecting Safety-Related Equipment (Generic Letter 89-13)

 July 18, 1989

TO:       ALL HOLDERS OF OPERATING LICENSES OR CONSTRUCTION PERMITS
          FOR NUCLEAR POWER PLANTS

SUBJECT:  SERVICE WATER SYSTEM PROBLEMS AFFECTING SAFETY-RELATED EQUIPMENT
          (GENERIC LETTER 89-13)


Purpose:

Nuclear power plant facilities of licensees and applicants must meet the 
minimum requirements of the General Design Criteria (GDC) in 10 CFR Part 50, 
Appendix A.  In particular, "GDC 44--Cooling Water" requires provision of a 
system (here called the service water system) "to transfer heat from struc-
tures, systems, and components important to safety to an ultimate heat sink" 
(UHS).  "GDC 45--Inspection of Cooling Water System" requires the system 
design "to permit appropriate periodic inspection of important components, 
such as heat exchangers and piping, to assure the integrity and capability of 
the system."  "GDC 46--Testing of Cooling Water System" requires the design 
"to permit appropriate periodic pressure and functional testing."  

In addition, nuclear power plant facilities of licensees and applicants must 
meet the minimum requirements for quality assurance in 10 CFR Part 50, 
Appendix B.  In particular, Section XI, "Test Control," requires that "a test 
program shall be established to assure that all testing required to 
demonstrate that structures, systems, and components will perform 
satisfactorily in service is identified and performed in accordance with 
written test procedures which incorporate the requirements and acceptance 
limits contained in applicable design documents."

Recent operating experience and studies have led the NRC to question the 
compliance of the service water systems in the nuclear power plants of 
licensees and applicants with these GDC and quality assurance requirements.  
Therefore, this Generic Letter is being issued to require licensees and appli-
cants to supply information about their respective service water systems to 
assure the NRC of such compliance and to confirm that the safety functions of 
their respective service water systems are being met.  

Background:

Bulletin No. 81-03:  The NRC staff has been studying the problems associated 
with service water cooling systems for a number of years.  At Arkansas Nuclear 
One, Unit 2, on September 3, 1980, the licensee shut down the plant when the 
NRC Resident Inspector discovered that the service water flow rate through the 



CONTACT:  C. Vernon Hodge, NRR
          492-1169


8907180211
.Generic Letter 89-13                  -2-                   July 18, 1989


containment cooling units did not meet the technical specification 
requirement.  The licensee determined the cause to be extensive flow blockage 
by Asiatic clams (Corbicula species, a non-native fresh water bivalve 
mollusk).  Prompted by this event and after determining that it represented a 
generic problem of safety significance, the NRC issued Bulletin No. 81-03, 
"Flow Blockage of Cooling Water to Safety System Components by Corbicula sp. 
(Asiatic Clam) and Mytilus sp. (Mussel)." 

The bulletin required licensees and applicants to assess macroscopic 
biological fouling (biofouling) problems at their respective facilities in 
accordance with specific actions.  A careful assessment of responses to the 
bulletin indicated that existing and potential fouling problems are generally 
unique to each facility ("Closeout of IE Bulletin 81-03...", NUREG/CR-3054), 
but that surprisingly, more than half the 129 nuclear generating units active 
at that time were considered to have a high potential for biofouling.  At that 
time, the activities of licensees and applicants for biofouling detection and 
control ranged widely and, in many instances, were judged inappropriate to 
ensure safety system reliability.  Too few of the facilities with high 
potential for biofouling had adopted effective control programs. 

Information Notice No. 81-21:  After issuance of Bulletin No. 81-03, one event
at San Onofre Unit 1 and two events at the Brunswick station indicated that 
conditions not explicitly discussed in the bulletin can occur and cause loss 
of direct access to the UHS.  These conditions include

     1.   Flow blockage by debris from shellfish other than Asiatic clams and 
          blue mussels. 

     2.   Flow blockage in heat exchangers causing high pressure drops that 
          can deform baffles and allow flow to bypass heat exchanger tubes.

     3.   A change in operating conditions, such as a change from power opera-
          tion to a lengthy outage, that permits a buildup of biofouling 
          organisms.  

The NRC issued Information Notice No. 81-21 to describe these events and 
concerns.

Generic Issue 51:  By March 1982, several reports of serious fouling events 
caused by mud, silt, corrosion products, or aquatic bivalve organisms in 
open-cycle service water systems had been received.  These events led to plant 
shutdowns, reduced power operation for repairs and modifications, and degraded 
modes of operation.  This situation led the NRC to establish Generic Issue 51, 
"Improving the Reliability of Open-Cycle Service Water Systems."  To resolve 
this issue, the NRC initiated a research program to compare alternative 
surveillance and control programs to minimize the effects of fouling on plant 
safety.  Initially, the program was restricted to a study of biofouling, but 
in 1987 the program was expanded to also address fouling by mud, silt, and 
corrosion products. 

This research program has recently been completed and the results have been 
published in "Technical Findings Document for Generic Issue 51...," NUREG/
CR-5210.  The NRC has concluded that the issue will be resolved when licensees 


.Generic Letter 89-13                  -3-                   July 18, 1989


and applicants implement either the recommended surveillance and control 
program described below (Enclosure 1) or its equivalent for the service water 
system at their respective facilities.  Many licensees experiencing service 
water macroscopic biofouling problems at their plants have found that these 
techniques will effectively prevent recurrence of such problems.  The examina-
tion of alternative corrective action programs is documented in "Value/Impact 
Analysis for Generic Issue 51...," NUREG/CR-5234.  

Continuing Problems:  Since the advent of Generic Issue 51, a considerable 
number of events with safety implications for the service water system have 
been reported.  A number of these have been described in information notices, 
which are listed in "Information Notices Related to Fouling Problems in 
Service Water Systems" (Enclosure 3).  Several events have been reported 
within the past 2 years:  Oconee Licensee Event Report (LER) 50-269/87-04, 
Rancho Seco LER 50-312/87-36, Catawba LER 50-414/88-12, and Trojan LER 
50-344/88-29.  In the fall of 1988, the NRC conducted a special announced 
safety system functional inspection at the Surry station to assess the 
operational readiness of the service water and recirculation spray systems.  A 
number of regulatory violations were identified (NRC Inspection Reports 
50-280/88-32 and 50-281/88-32).

AEOD Case Study:  In 1987, the Office for Analysis and Evaluation of 
Operational Data (AEOD) in the NRC initiated a systematic and comprehensive 
review and evaluation of service water system failures and degradations at 
light water reactors from 1980 to early 1987.  The results of this AEOD case 
study are published in "Operating Experience Feedback Report - Service Water 
System Failures and Degradations," NUREG-1275, Volume 3 (Enclosure 4).  

Of 980 operational events involving the service water system reported during 
this period, 276 were deemed to have potential generic safety significance.  A 
majority (58 percent) of these events with generic significance involved 
system fouling.  The fouling mechanisms included corrosion and erosion (27 
percent), biofouling (10 percent), foreign material and debris intrusion (10 
percent), sediment deposition (9 percent), and pipe coating failure and 
calcium carbonate deposition (1 percent).  

The second most frequently observed cause of service water system degradations 
and failures is personnel and procedural errors (17 percent), followed by 
seismic deficiencies (10 percent), single failures and other design deficien-
cies (6 percent), flooding (4 percent), and significant equipment failures (4 
percent).   

During this period, 12 events involved a complete loss of service water system 
function.  Several of the significant causes listed above for system degrada-
tion were also contributors to these 12 events involving system failure.

The study identified the following actions as potential NRC requirements.

     1.   Conduct, on a regular basis, performance testing of all heat 
          exchangers, which are cooled by the service water system and which 
          are needed to perform a safety function, to verify heat exchanger 
          heat transfer capability.
          
          
.Generic Letter 89-13                  -4-                   July 18, 1989


     2.   Require licensees to verify that their service water systems are not 
          vulnerable to a single failure of an active component.

     3.   Inspect, on a regular basis, important portions of the piping of the 
          service water system for corrosion, erosion, and biofouling.

     4.   Reduce human errors in the operation, repair, and maintenance of the 
          service water system.

Recommended Actions To Be Taken by Addressees:

On the basis of the discussion above, the NRC requests that licensees and 
applicants perform the following or equally effective actions to ensure that 
their service water systems are in compliance and will be maintained in 
compliance with 10 CFR Part 50, Appendix A, General Design Criteria 44, 45, 
and 46 and Appendix B, Section XI.  If a licensee or applicant chooses a 
course of action different from the recommendations below, the licensee or 
applicant should document and retain in appropriate plant records a 
justification that the heat removal requirements of the service water system 
are satisfied by use of the alternative program.  

Because the characteristics of the service water system may be unique to each 
facility, the service water system is defined as the system or systems that 
transfer heat from safety-related structures, systems, or components to the 
UHS.  If an intermediate system is used between the safety-related items and 
the system rejecting heat to the UHS, it performs the function of a service 
water system and is thus included in the scope of this Generic Letter.  A 
closed-cycle system is defined as a part of the service water system that is 
not subject to significant sources of contamination, one in which water 
chemistry is controlled, and one in which heat is not directly rejected to a 
heat sink.  If all these conditions are not satisfied, the system is to be 
considered an open-cycle system in regard to the specific actions required 
below.  (The scope of closed cooling water systems is discussed in the 
industrial standard "Operation and Maintenance of Nuclear Power Plants," 
ASME/ANSI OM-1987, Part 2.)

     I.   For open-cycle service water systems, implement and maintain an 
          ongoing program of surveillance and control techniques to signifi-
          cantly reduce the incidence of flow blockage problems as a result of 
          biofouling.  A program acceptable to the NRC is described in "Recom-
          mended Program to Resolve Generic Issue 51" (Enclosure 1).  It 
          should be noted that Enclosure 1 is provided as guidance for an 
          acceptable program.  An equally effective program to preclude 
          biofouling would also be acceptable.  Initial activities should be 
          completed before plant startup following the first refueling outage 
          beginning 9 months or more after the date of this letter.  All 
          activities should be documented and all relevant documentation 
          should be retained in appropriate plant records.

     II.  Conduct a test program to verify the heat transfer capability of all
          safety-related heat exchangers cooled by service water.  The total 
          test 
          
          
.Generic Letter 89-13                  -5-                   July 18, 1989


          program should consist of an initial test program and a periodic 
          retest program.  Both the initial test program and the periodic 
          retest program should include heat exchangers connected to or cooled 
          by one or more open-cycle systems as defined above.  Operating 
          experience and studies indicate that closed-cycle service water 
          systems, such as component cooling water systems, have the potential 
          for significant fouling as a consequence of aging-related in-leakage 
          and erosion or corrosion.  The need for testing of closed-cycle 
          system heat exchangers has not been considered necessary because of 
          the assumed high quality of existing chemistry control programs.  If 
          the adequacy of these chemistry control programs cannot be confirmed 
          over the total operating history of the plant or if during the 
          conduct of the total testing program any unexplained downward trend 
          in heat exchanger performance is identified that cannot be remedied 
          by maintenance of an open-cycle system, it may be necessary to 
          selectively extend the test program and the routine inspection and 
          maintenance program addressed in Action III, below, to the attached 
          closed-cycle systems.

          A program acceptable to the NRC for heat exchanger testing is de-
          scribed in "Program for Testing Heat Transfer Capability" (Enclosure 
          2).  It should be noted that Enclosure 2 is provided as guidance for 
          an acceptable program.  An equally effective program to ensure 
          satisfaction of the heat removal requirements of the service water 
          system would also be acceptable.  
          
          Testing should be done with necessary and sufficient 
          instrumentation, though the instrumentation need not be permanently 
          installed.  The relevant temperatures should be verified to be 
          within design limits.  If similar or equivalent tests have not been 
          performed during the past year, the initial tests should be 
          completed before plant startup following the first refueling outage 
          beginning 9 months or more after the date of this letter. 

          As a part of the initial test program, a licensee or applicant may 
          decide to take corrective action before testing.  Tests should be 
          performed for the heat exchangers after the corrective actions are 
          taken to establish baseline data for future monitoring of heat 
          exchanger performance.  In the periodic retest program, a licensee 
          or applicant should determine after three tests the best frequency 
          for testing to provide assurance that the equipment will perform the 
          intended safety functions during the intervals between tests.  
          Therefore, in the periodic retest program, to assist that 
          determination, tests should be performed for the heat exchangers 
          before any corrective actions are taken.  As in the initial test 
          program, tests should be repeated after any corrective actions are 
          taken to establish baseline data for future monitoring of heat 
          exchanger performance. 
          
          An example of an alternative action that would be acceptable to the 
          NRC is frequent regular maintenance of a heat exchanger in lieu of 
          testing for degraded performance of the heat exchanger.  This alter-
          native might apply to small heat exchangers, such as lube oil 
          coolers or pump bearing coolers or readily serviceable heat 
          exchangers located in low radiation areas of the facility.
          
          
.Generic Letter 89-13                  -6-                   July 18, 1989


          In implementing the continuing program for periodic retesting of 
          safety-related heat exchangers cooled by service water in open-cycle 
          systems, the initial frequency of testing should be at least once 
          each fuel cycle, but after three tests, licensees and applicants 
          should determine the best frequency for testing to provide assurance 
          that the equipment will perform the intended safety functions during 
          the intervals between tests and meet the requirements of GDC 44, 45, 
          and 46.  The minimum final testing frequency should be once every 5 
          years.  A summary of the program should be documented, including the 
          schedule for tests, and all relevant documentation should be 
          retained in appropriate plant records. 

     III. Ensure by establishing a routine inspection and maintenance program 
          for open-cycle service water system piping and components that 
          corrosion, erosion, protective coating failure, silting, and 
          biofouling cannot degrade the performance of the safety-related 
          systems supplied by service water.  The maintenance program should 
          have at least the following purposes:

          A.   To remove excessive accumulations of biofouling agents, corro-
               sion products, and silt;

          B.   To repair defective protective coatings and corroded service 
               water system piping and components that could adversely affect 
               performance of their intended safety functions.  

          This program should be established before plant startup following 
          the first refueling outage beginning 9 months after the date of this 
          letter.  A description of the program and the results of these 
          maintenance inspections should be documented.  All relevant documen-
          tation should be retained in appropriate plant records.

     IV.  Confirm that the service water system will perform its intended 
          function in accordance with the licensing basis for the plant.  
          Reconstitution of the design basis of the system is not intended.  
          This confirmation should include a review of the ability to perform 
          required safety functions in the event of failure of a single active 
          component.  To ensure that the as-built system is in accordance with 
          the appropriate licensing basis documentation, this confirmation 
          should include recent (within the past 2 years) system walkdown 
          inspections.  This confirmation should be completed before plant 
          startup following the first refueling outage beginning 9 months or 
          more after the date of this letter.  Results should be documented 
          and retained in appropriate plant records.  

     V.   Confirm that maintenance practices, operating and emergency proce-
          dures, and training that involves the service water system are 
          adequate to ensure that safety-related equipment cooled by the 
          service water system will function as intended and that operators of 
          this equipment will perform effectively.  This confirmation should 
          include recent (within the past 2 years) reviews of practices, 
          procedures, and training modules.  The intent of this action is to 
          
          
.Generic Letter 89-13                  -7-                   July 18, 1989


          reduce human errors in the operation, repair, and maintenance of the 
          service water system.  This confirmation should be completed before 
          plant startup following the first refueling outage beginning 9 
          months or more after the date of this letter.  Results should be 
          documented and retained in appropriate plant records. 

Reporting Requirements:

Pursuant to the provisions of Section 182a of the Atomic Energy Act of 1954, 
as amended, and 10 CFR 50.54(f), each licensee and applicant shall advise the 
NRC whether it has established programs to implement Recommendations I-V of 
this Generic Letter or that it has pursued an equally effective alternative 
course of action.  Each addressee's response to this requirement for 
information shall be made to the NRC within 180 days of receipt of this 
Generic Letter.  Licensees and applicants shall include schedules of plans for 
implementation of the various actions.  The detailed documentation associated 
with this Generic Letter should be retained in appropriate plant records.  

The response shall be submitted to the appropriate regional administrator 
under oath and affirmation under the provisions of Section 182a, Atomic Energy 
Act of 1954, as amended and 10 CFR 50.54(f).  In addition, the original cover 
letter and a copy of any attachment shall be transmitted to the U.S. Nuclear 
Regulatory Commission, Document Control Desk, Washington DC 20555, for 
reproduction and distribution.

In addition to the 180-day response, each licensee and applicant shall confirm 
to the NRC that all the recommended actions or their justified alternatives 
have been implemented within 30 days of such implementation.  This response 
need only be a single response to indicate that all initial tests or 
activities have been completed and that continuing programs have been 
established.

This request is covered by the Office of Management and Budget Clearance 
Number 3150-0011, which expires December 31, 1989.  The estimated average 
burden is 1000 man-hours per addressee response, including assessing the 
actions to be taken, preparing the necessary plans, and preparing the 180-day 
response.  This estimated average burden pertains only to these identified 
response-related matters and does not include the time for actual 
implementation of the recommended actions.  Comments on the accuracy of this 
estimate and suggestions to reduce the burden may be directed to the Office of 
Management and Budget, Reports Management, Room 3208, New Executive Office 
Building, Washington, DC 20503 and to the U.S. Nuclear Regulatory Commission, 
Records and Reports Management Branch, Office of Information and Resources 
Management, Washing-ton, DC 20555.

Although no specific request or requirement is intended, the following 
information would be helpful to the NRC in evaluating the cost of this Generic 
Letter:

     1.   Addressee time necessary to perform the requested confirmation and 
          any needed follow-up actions.

     2.   Addressee time necessary to prepare the requested documentation.  

.Generic Letter 89-13                  -8-                   July 18, 1989 


If there are any questions regarding this letter, please contact the regional 
administrator of the appropriate NRC regional office or your project manager 
in this office.

                              Sincerely,


                              James G. Partlow
                              Associate Director for Projects
                              Office of Nuclear Reactor Regulation

Enclosures:
1.  "Recommended Program to Resolve Generic Issue 51"
2.  "Program for Testing Heat Transfer Capability"  
3.  "Information Notices Related to Fouling Problems in Service Water Systems"
4.  "Operating Experience Feedback Report - Service Water System Failures and 
     Degradations in Light Water Reactors,"  NUREG-1275, Volume 3
5.   List of Most Recently Issued Generic Letters

.                                                             Enclosure 1


                               RECOMMENDED PROGRAM
                           TO RESOLVE GENERIC ISSUE 51


This enclosure describes a program acceptable to the NRC for meeting the 
objectives of the requested Action I in the proposed generic letter.  Both 
Action I and this enclosure are based upon the recommendations described in 
"Technical Findings Document for Generic Issue 51:  Improving the Reliability 
of Open-Cycle Service-Water Systems," NUREG/CR-5210, August 1988, and 
"Value/Impact Analysis for Generic Issue 51:  Improving the Reliability of 
Open-Cycle Service-Water Systems," NUREG/CR-5234, February 1989.  The NRC has 
concluded that Generic Issue 51 will be resolved when licensees and applicants 
implement either the recommended surveillance and control program addressed in 
this enclosure or an equally effective alternative course of action to satisfy 
the heat removal requirements of the service water system.

Water Source                  Surveillance                   Control
    Type                       Techniques                   Techniques

Marine or Estuarine                A                         B and C 
 (brackish) or Freshwater
  with clams

Freshwater
  without clams                    A and D                   B and C 

                       

A.   The intake structure should be visually inspected, once per refueling 
     cycle, for macroscopic biological fouling organisms (for example, blue 
     mussels at marine plants, American oysters at estuarine plants, and 
     Asiatic clams at freshwater plants), sediment, and corrosion.  
     Inspections should be performed either by scuba divers or by dewatering 
     the intake structure or by other comparable methods.  Any fouling 
     accumulations should be removed.

B.   The service water system should be continuously (for example, during 
     spawning) chlorinated (or equally effectively treated with another 
     biocide) whenever the potential for a macroscopic biological fouling 
     species exists (for example, blue mussels at marine plants, American 
     oysters at estuarine plants, and Asiatic clams at freshwater plants).  
     Chlorination or equally effective treatment is included for freshwater 
     plants without clams because it can help prevent microbiologically influ-
     enced corrosion.  However, the chlorination (or equally effective) 
     treatment need not be as stringent for plants where the potential for 
     macroscopic biological fouling species does not exist compared to those 
     plants where it does.  Precautions should be taken to obey Federal, 
     State, and local environmental regulations regarding the use of biocides.

C.   Redundant and infrequently used cooling loops should be flushed and flow 
     tested periodically at the maximum design flow to ensure that they are 
     not fouled or clogged.  Other components in the service water system 
     should be tested on a regular schedule to ensure that they are not fouled 
     or 
     .                                           -2-


     clogged.  Service water cooling loops should be filled with chlorinated 
     or equivalently treated water before layup.  Systems that use raw service 
     water as a source, such as some fire protection systems, should also be 
     chlorinated or equally effectively treated before layup to help prevent 
     microbiologically influenced corrosion.  Precautions should be taken to 
     obey Federal, State, and local environmental regulations regarding the 
     use of biocides.

D.   Samples of water and substrate should be collected annually to determine 
     if Asiatic clams have populated the water source.  Water and substrate 
     sampling is only necessary at freshwater plants that have not previously 
     detected the presence of Asiatic clams in their source water bodies.  If 
     Asiatic clams are detected, utilities may discontinue this sampling 
     activity if desired, and the chlorination (or equally effective) 
     treatment program should be modified to be in agreement with paragraph B, 
     above. 
.                                                             Enclosure 2


                  PROGRAM FOR TESTING HEAT TRANSFER CAPABILITY


This enclosure describes a program acceptable to the NRC for meeting the 
objectives of the requested Action II in the proposed generic letter.  Both 
Action II and this enclosure are based in part on "Operating Experience Feed-
back Report - Service Water System Failures and Degradations," NUREG-1275, 
Volume 3, November 1988 and "Technical Findings Document for Generic Issue 51: 
Improving the Reliability of Open Cycle Service Water Systems," NUREG/CR-5210, 
August 1988.  This enclosure reflects continuing operational problems, 
inspection reports, and industry standards ("Operation and Maintenance of 
Nuclear Power Plants," ASME/ANSI OM-1987, Part 2.)  The NRC requests licensees 
and applicants to implement either the steps addressed in this enclosure or an 
equally effective alternative course of action to satisfy the heat removal 
requirements of the service water system. 

Both the initial test program and the periodic retest program should include 
all safety-related heat exchangers connected to or cooled by one or more 
open-cycle service water systems.  A closed-cycle system is defined as a part 
of the service water system that is not subject to significant sources of 
contamination, one in which water chemistry is controlled, and one in which 
heat is not directly rejected to a heat sink.  (The scope of closed cooling 
water systems is discussed in the industrial standard, "Operation and 
Maintenance of Nuclear Power Plants," ASME/ANSI OM-1987, Part 2.)  If during 
the conduct of the total testing program any unexplained downward trend in 
heat exchanger performance is identified that cannot be remedied by 
maintenance of an open-cycle system, it may be necessary to selectively extend 
the test program to the attached closed-cycle system.

Testing should be done with necessary and sufficient instrumentation, though 
the instrumentation need not be permanently installed.  

As a part of the initial test program, a licensee or applicant may decide to 
take corrective action before testing.  Tests should be performed for the heat 
exchangers after the corrective actions are taken to establish baseline data 
for future monitoring of heat exchanger performance.  In the periodic retest 
program, a licensee or applicant should determine after three tests the best 
frequency for testing to provide assurance that the equipment will perform the 
intended safety functions during the intervals between tests.  Therefore, in 
the periodic retest program, to assist that determination, tests should be 
performed for the heat exchangers before any corrective actions are taken.  As 
in the initial test program, tests should be repeated after any corrective 
actions are taken to establish baseline data for future monitoring of heat 
exchanger performance.  

An example of an alternative action that would be acceptable to the NRC is 
frequent regular maintenance of a heat exchanger in lieu of testing for 
degraded performance of the heat exchanger.  This alternative might apply to 
small heat exchangers, such as lube oil coolers or pump bearing coolers or 
readily serviceable heat exchangers located in low radiation areas of the 
facility.

.                                      -2-


In implementing the continuing program for periodic retesting of 
safety-related heat exchangers cooled by service water in open-cycle systems, 
the initial frequency of testing should be at least once each fuel cycle, but 
after three tests, licensees and applicants should determine the best 
frequency for testing to provide assurance that the equipment will perform the 
intended safety functions during the intervals between tests and meet the 
requirements of GDC 44, 45, and 46.  The minimum final testing frequency 
should be once every 5 years.   

     I.   For all heat exchangers

          Monitor and record cooling water flow and inlet and outlet tempera-
          tures for all affected heat exchangers during the modes of operation 
          in which cooling water is flowing through the heat exchanger.  For 
          each measurement, verify that the cooling water temperatures and 
          flows are within design limits for the conditions of the 
          measurement.  The test results from periodic testing should be 
          trended to ensure that flow blockage or excessive fouling 
          accumulation does not exist.

    II.   In addition to the considerations for all heat exchangers in Item I, 
          for water-to-water heat exchangers

          A.   Perform functional testing with the heat exchanger operating, 
               if practical, at its design heat removal rate to verify its 
               capabilities.  Temperature and flow compensation should be made 
               in the calculations to adjust the results to the design 
               conditions.  Trend the results, as explained above, to monitor 
               degradation.  An example of this type of heat exchanger would 
               be that used to cool a diesel generator.  Engine jacket water 
               flow and temperature and service water flow and temperature 
               could be monitored and trended during the diesel generator 
               surveillance testing. 
               
          B.   If it is not practical to test the heat exchanger at the design 
               heat removal rate, then trend test results for the heat 
               exchanger efficiency or the overall heat transfer coefficient. 
               Verify that heat removal would be adequate for the system 
               operating with the most limiting combination of flow and 
               temperature.

   III.   In addition to the considerations for all heat exchangers in Item I, 
          for air-to-water heat exchangers

          A.   Perform efficiency testing (for example, in conjunction with 
               surveillance testing) with the heat exchanger operating under 
               the maximum heat load that can be obtained practically.  Test 
               results should be corrected for the off-design conditions.  
               Design heat removal capacity should be verified.  Results 
               should be trended, as explained above, to identify any degraded 
               equipment.

.                                      -3-


          B.   If it is not possible to test the heat exchanger to provide 
               statistically significant results (for example, if error in the  
               measurement exceeds the value of the parameter being measured), 
               then 

               1.   Trend test results for both the air and water flow rates 
                    in the heat exchanger.  

               2.   Perform visual inspections, where possible, of both the 
                    air and water sides of the heat exchanger to ensure 
                    cleanliness of the heat exchanger.

    IV.   In addition to the considerations for all heat exchangers in Item I, 
          for types of heat exchangers other than water-to-water or 
          air-to-water heat exchangers (for example, penetration coolers, oil 
          coolers, and motor coolers)

          A.   If plant conditions allow testing at design heat removal condi-
               tions, verify that the heat exchanger performs its intended 
               functions.  Trend the test results, as explained above, to 
               monitor degradation.  
               
          B.   If testing at design conditions is not possible, then provide 
               for extrapolation of test data to design conditions.  The heat 
               exchanger efficiency or the overall heat transfer coefficient 
               of the heat exchanger should be determined whenever possible. 
               Where possible, provide for periodic visual inspection of the 
               heat exchanger.  Visual inspection of a heat exchanger that is 
               an integral part of a larger component can be performed during 
               the regularly scheduled disassembly of the larger component.  
               For example, a motor cooler can be visually inspected when the 
               motor disassembly and inspection are scheduled.
               
               
.                                                             Enclosure 3


                INFORMATION NOTICES RELATED TO FOULING PROBLEMS 
                            IN SERVICE WATER SYSTEMS


     1.   Information Notice No. 83-46:  "Common-Mode Valve Failures Degrade 
          Surry's Recirculation Spray Subsystem,"  July 11, 1983

     2.   Information Notice No. 85-24:  "Failures of Protective Coatings in 
          Pipes and Heat Exchangers,"  March 26, 1985

     3.   Information Notice No. 85-30:  "Microbiologically Induced Corrosion 
          of Containment Service Water System,"  April 19, 1985

     4.   Information Notice No. 86-96:  "Heat Exchanger Fouling Can Cause 
          Inadequate Operability of Service Water Systems," November 20, 1986

     5.   Information Notice No. 87-06:  "Loss of Suction to Low Pressure 
          Service Water System Pumps Resulting from Loss of Siphon,"  
          January 30, 1987
Page Last Reviewed/Updated Friday, June 28, 2013