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                                 UNITED STATES
                         NUCLEAR REGULATORY COMMISSION
                     OFFICE OF NUCLEAR REACTOR REGULATION
                         WASHINGTON, D.C.  20555-0001

                                 April 4, 1997


NRC INFORMATION NOTICE 97-16:  PRECONDITIONING OF PLANT STRUCTURES,            
                               SYSTEMS, AND COMPONENTS BEFORE ASME             
                               CODE INSERVICE TESTING OR TECHNICAL             
                               SPECIFICATION SURVEILLANCE TESTING


Addressees 

All holders of operating licenses or construction permits for nuclear power
reactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information
notice to alert addressees to the potential for maintenance activities
performed before surveillance testing ("preconditioning" or "grooming") to
adversely affect the validity of the surveillance test results for structures,
systems, and components (SSCs or equipment).  It is expected that recipients
will review the information for applicability to their facilities and consider
actions, as appropriate, to avoid similar problems.  However, suggestions
contained in this information notice are not NRC requirements; therefore, no
specific action or written response is required.  

Background

The NRC has had a longstanding concern about unacceptable preconditioning or
grooming of various SSCs before the performance of Technical Specification
(TS) surveillance tests or testing required by the American Society of
Mechanical Engineers Boiler and Pressure Vessel Code (the ASME Code) and the
adverse effect such activity might have on the validity of the test results.

Description of Circumstances

In recent years, inspection findings and notices of violation have revealed
that licensees are performing unacceptable preconditioning activities.  The
following examples are summaries of inspection findings; additional details on
each example can be found in the referenced inspection reports.  

Circuit Breakers

NRC Inspection Report (IR) 50-298/94-16 (Accession No. 9409150141) for Cooper
Nuclear Station identified that electrical loads were removed from a number of
480-volt circuit breakers before surveillance testing was performed.  The NRC
staff identified this as an 


9704010236.                                                            IN 97-16
                                                            April 4, 1997
                                                            Page 2 of 5


example of unacceptable preconditioning, a concern addressed in NRC
Confirmatory Action Letter issued on July 1, 1994.  This concern formed part
of the basis for a Severity Level III violation of 10 CFR Part 50, Appendix B,
Criterion XI, "Test Control," issued on December 12, 1994 (Accession No.
9412140006).  In addition, IR 50-298/94-16 discussed a surveillance procedure
that contained instructions requiring technicians to inspect, clean, and
lubricate several breakers before performing the "as-found" testing of several
breaker functions.  Since these functions (e.g., trip force of the operating
mechanism, undervoltage trip, time delay attachments, etc.) could have been
affected by the cleaning and lubrication, the test results did not represent
the as-found condition of the breakers. 

In NRC IR 50-298/94-31 (Accession No. 9506280604) for Cooper station, the NRC
staff evaluated the effectiveness of the licensee's corrective actions in
response to the preconditioning issues identified in IR 50-298/94-16.  In
order to address this violation, the licensee had reviewed over 6,400
procedures, including maintenance procedures, and found approximately 168
procedures that contained potential preconditioning activities.  The
inspectors verified that the licensee had revised these procedures to address
these concerns.  
Emergency Diesel Generators

NRC IR 50-315/316-95010(DRP) (Accession No. 9511280025) for D.C. Cook
identified that the licensee's policy was to use the air start system to turn
over (roll) the emergency diesel generator (EDG) crankshafts with the cylinder
petcocks open to purge (blow down) any accumulated water or oil before the
surveillance test was performed.  Since this activity was performed to prevent
potential damage caused by hydrolocking during the surveillance test starts,
the safety benefit of rolling the diesels outweighed the benefit of testing in
the as-found condition.  However, the staff was concerned that air start
valves were used (unnecessarily) to roll the EDGs when this activity could
have been performed manually by "barring over" the crankshaft.  Barring over
the crankshaft would have avoided the possibility of preconditioning the air
start valves and would have ensured that they were being tested in an as-found
condition.  NRC IR 50-315/316-95013(DRP) (Accession No. 9602200321) identified
the practice of using the air start system to roll the EDGs prior to
surveillance testing as a failure to test safety-related equipment under
suitably controlled conditions and in accordance with design and licensing
bases.  This failure was cited as a violation of 10 CFR Part 50, Appendix B,
Criterion II, "Quality Assurance Program."

Hydrogen Analyzer Calibration

NRC IR 50-416/95-21 (Accession No. 9602290202) for the Grand Gulf Nuclear
Station identified that the containment and drywell hydrogen analyzer
calibration surveillance procedure required technicians to check reagent gas
flow before calibration of the analyzer and to make an adjustment, if
necessary, to the previous test value before obtaining the "as-found"
calibration data.  Since adjusting the reagent gas flow could change the as-
found condition of the analyzer and invalidate the surveillance test results,
the inspectors.                                                            IN 97-16
                                                            April 4, 1997
                                                            Page 3 of 5


determined that the test procedure was inadequate and cited it as a violation
of TS 5.4.1.a., which requires that specific written procedures be established
for surveillance tests as described in Regulatory Guide 1.33, "Quality
Assurance Program Requirements."  

Turbine Driven Auxiliary Feedwater Pumps

NRC IR 50-315/316-95013(DRP) (Accession No. 9602200321) for D.C. Cook Units 1
and 2 identified the practice of operating the turbine-driven auxiliary
feedwater pumps immediately before performing the surveillance tests and the
practice of venting the residual heat removal pumps immediately before
performing surveillance tests as examples of unacceptable preconditioning. 
The failure to test safety-related equipment under suitably controlled
conditions and in accordance with design and licensing bases was cited as a
violation of  10 CFR Part 50, Appendix B, Criterion II.

High-Pressure Coolant Injection and Reactor Core Isolation Cooling

NRC IR 50-298/95-04 (Accession No. 9505230003) for Cooper Nuclear Station
indicated that plant operators had recognized that performing a series of
different high-pressure coolant injection system and reactor core isolation
cooling surveillance tests in sequence, without allowing sufficient time for
the systems to cool down between tests, would constitute unacceptable
preconditioning.  However, the operators did not identify nor document the
full extent of the preconditioning concerns, nor did they initiate appropriate
corrective actions to ensure that preconditioning would not be repeated.  The
failure of the operators to fully recognize and initiate action to correct
preconditioning concerns was cited as a violation of  10 CFR Part 50, Appendix
B, Criterion V, "Instructions, Procedures, and Drawings."

Motor Operated Valves

NRC IR 50-335/96-11, 50-389/96-11 (Accession No. 9609170377) for the St. Lucie
reactor facility identified that the four containment spray flow control
valves (two for each unit) were being unacceptably preconditioned prior to
surveillance testing.  Specifically, the valve stems were being lubricated
prior to performing stroke time testing.  The failure of the licensee's
administrative procedures to ensure that these stroke time tests were
performed under suitably controlled conditions was cited as a violation of 10
CFR Part 50, Appendix B, Criterion XI, "Test Control."

Discussion

As illustrated in the above-mentioned examples, some licensees are continuing
to perform maintenance activities or to take other preconditioning actions
that were found to be unacceptable.  When performing technical specification
surveillance and ASME Code inservice testing, the equipment is typically
tested in the as-found condition.  However, experience has demonstrated that
some surveillance testing cannot be performed without disturbing or altering
the equipment (e.g., attachment of test leads, pneumatic or hydraulic supply
lines).  For example, circuit breakers may be required to be racked out and
installed on a test rig in order to perform some surveillance tests.  However,
cycling, cleaning, and .                                                            IN 97-16
                                                            April 4, 1997
                                                            Page 4 of 5


lubrication were not necessary in order to perform the surveillance test. 
Similarly, other equipment, such as valves, pumps, and motors may require
disconnection, realignment, installation of jumpers, or other alterations in
order to perform the surveillance tests.

Any such disturbance or alteration would be expected to be limited to the
minimum necessary to perform the test and prevent damage to the equipment.  

In certain cases, the safety benefit of some preconditioning activities may
outweigh the benefits of testing in the as-found condition.  For example, the
staff has  approved the practice of routine checking of EDG cylinders for
water accumulation before performing surveillance tests in order to prevent
the damage caused by hydrolocking.  In the previously described EDG example,
the concern was that use of the air start valves was not needed to roll the
EDG and purge the cylinders.  

The following guidance has been provided to NRC inspectors:  

1.    Inspection Procedure (IP) 61726, "Surveillance Operations," directs
      inspectors to conduct a detailed technical review of the licensee's
      surveillance procedure and evaluate its adequacy to demonstrate that the
      system components will function under design-basis conditions and that
      any preconditioning required by the procedure is acceptable.  

2.    IP 62707, "Maintenance Observation," cautions inspectors to verify that
      preventive maintenance (PM) activities are not routinely being scheduled
      to "precondition" equipment before performing surveillance tests in
      order to ensure that the test is passed satisfactorily.  It directs
      inspectors to examine the sequence of PM activities to determine whether
      the licensee routinely schedules PM activities before surveillance
      tests. 

3.    NUREG-1482, "Guidelines for Inservice Testing at Nuclear Power Plants,"
      Section 3.5, notes that the as-found condition is generally considered
      to be the condition of a valve without pre-stroking or maintenance and
      that most inservice testing is performed in a manner that generally
      represents the condition of a standby component if it were actuated in
      the event of an accident (i.e., no preconditioning before actuation).   
      

Related Generic Communications

The NRC staff has addressed the issue of preconditioning in previous generic
communications including Information Notice (IN) 96-24, "Preconditioning of
Molded-Case Circuit Breakers Before Surveillance Testing," and IN 93-63,
"Periodic Testing and Preventive Maintenance of Molded-Case Circuit Breakers."
.                                                            IN 97-16
                                                            April 4, 1997
                                                            Page 5 of 5


This information notice requires no specific action or written response.  If
you have any questions about the information in this notice, please contact
the technical contact listed below or the appropriate Office of Nuclear
Reactor Regulation (NRR) project manager.


                                                signed by T. R. Quay

                                    Thomas T. Martin, Director
                                    Division of Reactor Program Management
                                    Office of Nuclear Reactor Regulation

Technical contact:  Charles D. Petrone, NRR
                    (301) 415-1027
                    E-mail:  [email protected]