**ATTACHMENT 71111.HS**

INSPECTABLE AREA: Heat Sink Performance - Pilot

CORNERSTONES: Initiating Events (20%)

> Mitigating Systems (80%)

INSPECTION BASES: Heat exchangers and heat sinks are required to remove
decay heat, and provide cooling water for operating equipment.
Degradation in performance can result in failure to meet system success
criteria, and lead to increased risk primarily due to common cause
failures. This inspectable area verifies aspects of the associated
cornerstones for which there are no indicators to measure performance.

LEVEL OF EFFORT: In accordance with Section 02.01, one or two
observations of heat exchanger performance testing, or one review of
heat exchanger performance test data, or verification of the licensee=s
execution and on-line monitoring of biofouling controls and cleanliness
of heat exchanger tubes on a biennial basis.

> One heat exchanger/heat sink performance inspection per Section 02.02
> by the resident staff on a biennial basis
>
> NOTE: The testing and inspection performance review conducted in
> accordance with Section 02.01 is performed by the resident inspection
> staff on a biennial basis. The heat exchanger/heat sink programmatic
> and functional performance review conducted in accordance with Section
> 02.02 on a biennial basis by the resident staff [will not be performed
> during the same calendar year]{.underline} as the Section 02.01
> requirement.

71111.HS-01 INSPECTION OBJECTIVES

01.01 To verify that any potential heat exchanger deficiencies which
could mask degraded performance are identified. Applies to all heat
exchangers connected to safety related service water systems.

01.02 To verify that any potential common cause heat sink performance
problems that have the potential to increase risk are identified, i.e.,
icing at circulating and service water intake structures.

01.03 To verify that the licensee has adequately identified and resolved
heat sink performance problems that could result in initiating events or
affect multiple heat exchangers in mitigating systems and thereby
increase risk, i.e., component cooling water heat exchanger performance
affected by corrosion, fouling, or silting.

71111.HS-02 INSPECTION REQUIREMENTS

02.01 [Biennial Testing and Inspection Performance Review]{.underline}.
Verify acceptable heat exchanger performance on a continuing basis by
either observing the type of tests generally employed by industry, by
reviewing the resulting test data of those tests, or by utilizing the
periodic maintenance method outlined in EPRI NP-7552. Observe one or two
heat exchanger performance tests, review the test data from one or two
heat exchanger performance tests, or verify licensee=s execution and
on-line monitoring of biofouling controls and cleanliness of a heat
exchanger=s tubes on an annual basis. Select a heat exchanger in a
system that transfers heat directly to the safety-related service water
system, and that is ranked high in the plant specific risk assessment.
Verify the following items, as applicable:

> a\. Test acceptance criteria and results have appropriately considered
> differences between testing conditions and design conditions
> (functional testing at design heat removal rate may not be practical).
>
> b\. Inspection results are appropriately categorized against
> pre-established engineered acceptance criteria, and are acceptable.
> Primarily focus on whether the number of tubes plugged affects the
> heat exchanger=s operability and not the biofilm on the inside of
> tubes which should be covered in the biennial inspection by a
> specialist.
>
> c\. Frequency of testing or inspection is sufficient (given the
> potential for fouling) to detect degradation prior to loss of heat
> removal capabilities below design basis values.
>
> d\. Test results have considered test instrument inaccuracies and
> differences.

e.  Licensee has developed acceptance criteria for its bio-fouling
    controls.

02.02 [Biennial Programmatic and Functional Performance
Review]{.underline}

> a\. Select 2-3 heat exchangers for systems that are ranked high in the
> plant specific risk assessment. This includes all heat exchangers
> [directly or indirectly connected]{.underline} to the safety-related
> service water system.
>
> b\. For the selected heat exchangers [that are also directly
> connected]{.underline} to the service water system, verify that
> testing, inspection/maintenance, or monitoring of biotic fouling
> controls are singularly or in combination adequate to ensure proper
> heat transfer.
>
> 1\. Review the method and results of heat exchanger performance
> testing or equivalent methods to verify performance. Verify the
> following items, as applicable:
>
> \(a\) The selected test methodology is consistent with accepted
> industry practices, or equivalent.
>
> \(b\) Test conditions (e.g., differential temperatures, differential
> pressures, and flows) are consistent with the selected methodology.
>
> \(c\) Test acceptance criteria (e.g., fouling factors, heat transfer
> coefficients) are consistent with the design basis values.
>
> \(d\) Test results have appropriately considered differences between
> testing conditions and design conditions (functional testing at design
> heat removal rate may not be practical).
>
> \(e\) Frequency of testing based on trending of test results is
> sufficient (based on trending data) to detect degradation prior to
> loss of heat removal capabilities below design basis values.
>
> \(f\) Test results have considered test instrument inaccuracies and
> differences.

(g) Tube and shell side heat loads are equal if adequate information is
    available in test results to calculate these two values.

> 2\. For inspection/cleaning, review the methods and results of heat
> exchanger performance inspections or observe the actual inspection/
> cleaning. Verify the following first three steps ((a)-(c)) if
> conducting the review and the last step (d) only if actually observing
> the inspection/cleaning:
>
> \(a\) Methods used to inspect heat exchangers are consistent with
> expected degradation.
>
> \(b\) Established acceptance criteria are consistent with accepted
> industry standards, or equivalent, including acceptability of the
> cleaning interval.
>
> \(c\) As found results are appropriately dispositioned such that the
> final condition is acceptable.

(d) If observing the inspection/cleaning then perform the following:

> \(1\) Prior to cleaning, inspect the extent of fouling and blockage of
> tubes.
>
> \(2\) Inspect the condition of the cleaned surfaces.
>
> \(3\) Verify that the number of plugged tubes are within the limit of
> operability of the heat exchanger and are appropriately accounted for
> in heat exchanger performance calculations.
>
> 3\. When implemented, verify that chemical treatments, tube leak
> monitoring, methods used to control biotic fouling corrosion (such as
> shells, seaweed, corbicula, and microbiological induced corrosion),
> and methods to control macrofouling (silt, dead mussel shells, debris,
> etc.) are sufficient (e.g., appropriate acceptance criteria) to ensure
> required heat exchanger performance.
>
> c\. For the selected heat exchangers [either directly or indirectly
> connected, except as noted,]{.underline} to the service water system,
> verify the following:
>
> 1\. Condition and operation are consistent with design assumptions in
> heat transfer calculations, e.g. for tube plugging.
>
> 2 Licensee has evaluated the potential for water hammer in those heat
> exchangers and undertaken appropriate measures to address it.

3.  The heat exchangers do not exhibit excessive vibration during
    operation that could potentially damage their tubes or tubesheets
    based on direct observation or issues identified in
    corrective-action documents.

4.  For heat exchangers [indirectly connected]{.underline} to the
    service water system, that the water chemistry is being adequately
    controlled to discourage corrosion , e.g. stress corrosion cracking,
    in its metallic sub-components .

5.  Redundant and infrequently used heat exchangers are flow tested
    periodically at maximum design flow.

> d\. Verify the performance of ultimate heat sinks and their
> subcomponents like piping, intake screens, pumps, valves, etc by tests
> or other equivalent methods. For heat sinks, the issue is their
> availability and accessibility to the in-plant cooling water systems.
> The inspector should check two of the following for heat sinks and
> their subcomponents as applicable:
>
> 1\. Sufficient reservoir capacity.
>
> 2\. Third party dam inspections for integrity of heat sink
>
> 3\. Free from clogging due to macrofouling (silt, dead mussel shells,
> debris, etc.)
>
> 4\. Licensee has in place adequate controls for biotic fouling.
>
> 5\. Functionality during adverse weather conditions, e.g. icing or
> high temperatures.

6.  Performance tests for pumps and valves in service water system.

02.03 [Identification and Resolution of Problems]{.underline}. Verify
that the licensee has entered significant heat exchanger/sink
performance problems in the corrective action program. Select for review
2 -3 issues in the licensee=s corrective action program related to
degraded heat exchanger/sink performance including issues related to
silting, corrosion, fouling, and heat exchanger testing then verify that
licensee corrective actions are appropriate. See Inspection Procedure
71152, AIdentification and Resolution of Problems,@ for additional
guidance.

71111.HS-03 INSPECTION GUIDANCE

[General Guidance]{.underline}

Refer to the table below for selecting inspection activities to achieve
each cornerstone objective and to those activities that have a risk
priority i.e., those common-cause failures with a reasonable probability
of occurring should be targeted by inspection to determine impact on
cornerstones.

  ----------------- -------------------- ----------------- -----------------
  **Cornerstone**   **Inspection         **Risk Priority** **Example**
                    Objective**                            

  Initiating Events Evaluate events,     Common-cause      Icing of a
                    issues, or           issues affecting  circulating water
                    conditions involving heat removal      and service water
                    the degradation or   capabilities.     intake structure.
                    loss of both the                       
                    normal and ultimate                    
                    heat sinks.                            

  Mitigating        Evaluate any         Heat exchanger    Degraded
  Systems           potential degraded   selection should  containment
                    performance of heat  focus on the      cooling or
                    exchangers           potential for     component cooling
                                         common-cause      water heat
                                         failures or on    exchanger
                                         potentially high  performance due
                                         risk heat         corrosion,
                                         exchangers with a fouling, silting,
                                         low margin to     etc.
                                         their design      
                                         point or the high 
                                         potential for     
                                         fouling.          
  ----------------- -------------------- ----------------- -----------------

[Specific Guidance]{.underline}

03.01 No specific guidance

03.02 [Biennial Review]{.underline}

d.  There is no limitation on the type and size of heat exchangers that
    can be selected as long as they are cooled by the safety-related
    service water system or the credited water system cooled by the
    ultimate heat sink and they are ranked high in the plant specific
    risk assessment. The credited water source is the one relied on in
    accident analyses in the licensee=s safety analysis report.

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b.  For this requirement, if possible, focus on the credited water
    source as defined in 03.02a. above. Of the heat exchangers selected
    only those directly cooled by the safety-related service water
    system should be reviewed or evaluated for this inspection
    requirement in accordance with Generic Letter 89-13.

> 1\. No specific guidance
>
> (a -c) No specific guidance
>
> (d). Test results need to be extrapolated to the heat exchanger design
> conditions.
>
> \(e\) Trending of the results of heat exchanger performance tests
> should not have abrupt step changes without the licensee providing
> some valid justification as to the reason for the deviation..
>
> \(f\) Test instruments should be calibrated and set on appropriate
> range for the parameters to be measured, otherwise small measurement
> errors could affect the test results. The required accuracy of the
> instruments depends on the margins available between the calculated
> parameter based on the test results and the limiting design condition.
>
> \(g\) No specific guidance
>
> 2\. No specific guidance
>
> 3\. No specific guidance

c.  This inspection requirement should target those design and
    operational requirements other than those evaluated by performance
    testing or inspection/cleaning.

> 1\. The inspector can refer to either design assumptions in
> calculations or also parameters on design data sheet that can be
> evaluated by observation not testing.
>
> 2\. No specific guidance
>
> 3\. No specific guidance

4.  This inspection requirement is only applicable to those heat
    exchangers cooled by safety-related service water or the credited
    water source as defined above in 03.02a. and which are also in
    closed loop systems.

    5.  No specific guidance

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d.  For this requirement focus on the credited water source as defined
    in 03.02a. above. The inspector should assess whether the ultimate
    heat sink and its subcomponents are capable of performing their
    intended safety functions. Only two of the listed parameters which
    are applicable for the respective plant should be reviewed on a
    biennial basis.

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32532. No specific guidance

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2.  Some plants may not have dams which encapsulate the ultimate heat
    sink so this requirement will not be applicable.

3.  This requirement can be satisfied by test results, observation, or
    other equivalent methods that verify ultimate heat sink and
    subcomponents can accommodate maximum system flow.

4.  Best verified by checking conformance with the acceptance criteria
    adopted by the licensee for checking the adequacy of the licensee=s
    biotic fouling controls.

5.  This inspection requirement should determine whether licensee has
    procedures to deal with adverse weather conditions. Coordinate the
    performance of this step with the inspection requirements of IP
    71111.01, AAdverse Weather Protection.@

6.  No specific guidance

[Identification and Resolution of Problems]{.underline}

The inspector should focus on events or conditions that could cause the
loss of a heat exchanger/sink due to events such as heat transfer
problems, improper cleaning, ice buildup, grass intrusion, or blockage
of pipes and components. The inspector should determine whether the
licensee has appropriately considered common-cause failures. If any loss
of heat exchanger/sink events have occurred, these should receive the
priority for review. Review the corrective actions to determine if
actions were sufficient to prevent recurrence of the problem. Refer to
IP 71152, AIdentification and Resolution of Problems,@ for further
guidance in this area.

71111.HS-04 RESOURCE ESTIMATE

This inspection procedure is estimated to take, on average, 6 to 8 hours
for the Biennial Testing and Inspection Performance review and 34 to 40
hours for the Biennial Programmatic and Functional Performance review at
a site regardless of the number of units at that site. These estimates
depend on the number of heat exchangers/sinks tested by the licensee
during the inspection period.

71111.HS-05 COMPLETION STATUS

Inspection of the minimum sample size will constitute completion of this
procedure in the RPS. That minimum sample size will consist of one
sample of performance reviews of one heat exchanger on a biennial basis,
and two samples consisting of the reviews of two heat exchangers for
performance, inspection/cleaning, and required bio-fouling controls
along with the review of certain aspects of the ultimate heat sink and
its subcomponents on a biennial basis.

During the pilot, the sample for heat sink performance review will be
recorded under 71111.07A in RPS.

During the pilot, the two samples for heat exchanger performance will be
recorded under 71111.07B in RPS.

71111.HS-06 REFERENCES

EPRI NP-7552 Heat Exchanger Performance Monitoring Guidelines

ASME OM-S/G Part 21 Inservice Performance Testing of Heat Exchangers in
Light-Water Reactor Power Plants

NUREG 1275 Vol. 3 Operating Experience Feedback Report- Service Water
System Failures and Degradations

NUREG/CR-5865 Generic Service Water System Risk-Based Inspection Guide

NUREG/CR-0548 Ice Blockage of Water Intakes

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

END