View source for 05000458/LER-1986-060, Forwards Info Re Items Identified Subsequent to 861110 Conference Re Insp Rept 50-458/86-36.Addl Info Available in LER 86-60,submitted on 861113

{{Adams
| number = ML20214L013
| issue date = 11/13/1986
| title = Forwards Info Re Items Identified Subsequent to 861110 Conference Re Insp Rept 50-458/86-36.Addl Info Available in LER 86-60,submitted on 861113
| author name = Cahill W
| author affiliation = GULF STATES UTILITIES CO.
| addressee name = Martin R
| addressee affiliation = NRC OFFICE OF INSPECTION &amp; ENFORCEMENT (IE REGION IV)
| docket = 05000458
| license number = 
| contact person = 
| document report number = RBG-24-800, NUDOCS 8612020544
| document type = CORRESPONDENCE-LETTERS, INCOMING CORRESPONDENCE, UTILITY TO NRC
| page count = 2
}}
{{LER
| Title = Forwards Info Re Items Identified Subsequent to 861110 Conference Re Insp Rept 50-458/86-36.Addl Info Available in LER 86-60,submitted on 861113
| Plant = 
| Reporting criterion = 
| Power level = 
| Mode = 
| Docket = 05000458
| LER year = 2086
| LER number = 60
| LER revision = 
| Event date = 
| Report date = 
| ENS = 
| abstract = 
}}

=text=
{{#Wiki_filter:a s *"
  #      .4
: e.   =2 GULF STATES                    UTILITIES COMPANY
                                                                                     .g POST O F F IC E B o x 2 9 51
* OEAUMONT. TEXAS 77704 AREA CODE 713 838-6631 November 13, 1986 RBG 24,800 File Nos. G9.5, G9.25.1.5 Mr. Robert D. Martin, Regional Administrator U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 1000                        .
M@     0WS    %
Arlington, TX 76011

==Dear Mr. Martin:==

J                 3 River Bend Station - Unit 1 j                                j Docket No. 50-458 As discussed on November 12, 1986 with the River Bend Station Senior Resident Inspector, attached                is     information  which addresses items identified subsequent to the conference of November 10, 1986 regarding Inspection Report 50-458/86-36.
Other information is available in our Licensee Event Report No.
86-60 also submitted today. If any additional information is required, please let me know.
Sincerely, W.    . Cahill, J .
Senior Vice President River Bend Nuclear Group WJC/ ERG /j e Attachment 8612O20544 861113 b 3k 7
PDR     ADOCK 05000458 r
        ~
1
()          G                      PDR Jl                                                                                             s\
6

                                      }
f                           . t
                                             .     .a ATTACHMENT Calculations were prepared for the Control Building which show that room temperatures would not have exceeded the design limits following a Loss of Coolant Accident (LOCA) with offsite power available and failure of an air handling unit (AHU) assuming manual actuation of the system twenty (20) minutes after the event. The calculations analyzed the main control room, the switchgear room and the DC equipment room based upon the heat source, heat      sinks,   initial   temperatures    and   equipment qualification temperatures applicable to each zone. Each of these zones were shown to have temperatures below their limiting equipment     qualification temperatures after twenty-five (25) minutes with a complete loss of ventilation. Discussions at the conference identified the control room as an example of these analyses, but all areas of the Control Building were considered.
Reviews have identified the following types of indications to be available to the operators in the control room.
Air handling unit trip (Main Control Room & Switchgear Room)
Air handling unit discharge temperature high (Main Control Room and Switchgear Room)
High room temperatures (Switchgear Room)
Damper misalignment (Main Control Room)
Divisional Control Building Ventilation System inoperable (Main Control Room, Switchgear Room and Chiller Room)
Anis latter alarm can be initiated by several conditions which include:
Motor trip of AHU for Main Control Room, Switchgear Room or Control Room Control power loss or trip of Air Operated Daupers (AODs) associated with the Main Control Room and Switchgear Room.
(There are no A0Ds associated with the Chiller Room.)
These alarms would provide indications to the operator of trouble in the system. The alarm response procedures will then cause him to take action to start the redundant system. Since River Bend Station analyzed for action at twenty-five minutes into the event, at least five minutes margin is provided.
_ - - - _ . - _ _ . - _ _ _ _ _ -                -.
}}

{{LER-Nav}}