Scram Discharge Volume Designs (Generic Letter 80-64)

GL80064 

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

                               July 7, 1980 

TO ALL OPERATING BOILING WATER REACTORS (BWR's) 

Gentlemen: 

As you know, the staff has proposed improvements in the scram discharge 
volume (SDV) designs for BWR control rod drive systems to reduce 
susceptibility to common cause failures (NUREG-0460). We now request that 
you amend the Technical Specifications for your facility with respect to 
control rod drive scram discharge volume capability. The basis for our 
request is founded in events which have occurred in operating BWR's 
involving cause failures of SDV limit switches and SDV drain valve 
operability. In IE Bulletin 80-14 dated June 13, 1980, you were requested to 
implant procedures and administrative controls to ensure that the SDV is 
operable during reactor operation. While the function of the bulletin was to 
effect immediate action with regard to this problem, the proposed Technical 
Specifications will strengthen the provisions for assuring continued 
operability of the control rod drive system during reactor operation. 

You are requested to propose Technical Specification changes for your 
facility to provide surveillance requirements for SDV vent and drain valves 
and LCO/surveillance requirements for RPS and control rod block SDV limit 
switches. To assist you in preparing your submittal, we have enclosed a copy
of Model Technical Specifications which would be sufficient to provider the 
assurance we seek. These Technical Specifications have proposed by our staff
to be incorporated into the next revision of the General Electric Standard 
Technical Specifications. Applicable changes are marked by vertical lines in
the margins. Unchanged pages are included for completeness. Your proposal 
should use the enclosure as a guide and should include an appropriate Safety
Analysis as a basis. 

It is requested that you submit your proposed Technical Specifications with 
the basis within 90 days of receipt of this letter. If you have any 
questions about this request, please contact your Project Manager. 

                                             Sincerely, 


                                             Darrell G. Eisenhut, Director 
                                             Division of Licensing 

Enclosure: 
Model Technical Specifications