Steam Generator Information System (Generic Letter 77-06)

                                                               GL 77-06

                                UNITED STATES 
                         NUCLEAR REGULATORY COMMISSION
                            WASHINGTON, D.C. 20555

                              December 9, 1977

TO ALL PWR FACILITY LICENSES


Gentlemen:  

The NRC staff has recently been engaged in a series of discussions with
reactor vendors, EPRI, and the Steam Generator Owners Groups concerning steam
generator operational problems.  Central to these discussions is an accurate
assessment of operational conditions and experiences as well as the programs
aimed towards the resolution of these problems.

In order to ensure that both the NRC and the nuclear industry have available a
comprehensive collection of operating data for steam generators to permit
informed, timely decisions and actions, DOR is establishing a steam generator
information system.  The system will collect appropriate information from all
PWR licensees which will periodically be published.  It is presently
anticipated that the initial publication of information will be in the early
part of 1978.  You will be sent a copy of this and all future publications.

This information system will enable the NRC and each Licensee to draw from the
operational experiences of the entire nuclear industry when making any
decisions concerning steam generators.  This should result in both safety and
economic benefits.

Enclosed is a questionnaire which we request that you complete for each of
your operating PWR units.  We believe that the questionnaire is self
explanatory, however, if questions arise or any clarifications are necessary,
please do not hesitate to contact your NRC Project Manager.  Please include
with your response any diagrams you may have available which illustrate the
tube plugging and/or the tube degradation patterns.

To enable us to maintain the information current, you are further requested to
submit in the same format indicated by the questionnaire any changes or
additions to your initial submittal to reflect the future operating experience
with your steam generators, i.e., the results of future steam generator
inspections.  The questionnaire should be completed to the extent applicable
and appropriate at this time, i.e., regardless of operating experience.



8004010589
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The information being requested is quite extensive and will require a diligent
effort on your part and ours to assure accurate and timely completion.  Also,
we realize that parts of the information may already be available to the NRC,
but not in a convenient format which is readily accessible.  Therefore, we
request that you assist us by returning a single completed copy of the
enclosed questionnaire to the Director of Nuclear Regulation, U.S. Nuclear
Regulatory Commission, Washington, D.C. 20555, within 60 days of receipt of
this letter.  Please include any comments or suggestions for improving this
information system which you may have. 

This request for generic information was approved by GAO under a blanket
clearance number R0071; this clearance expires September 30, 1978.

                                      Sincerely,


                                      Karl R. Goller, Assistant Director
                                        for Operating Reactors
                                      Division of Operating Reactors

Enclosure:  
Steam Generator Operating History Questionnaire