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{{Adams
#REDIRECT [[IR 05000344/1986006]]
| number = ML20141C743
| issue date = 03/21/1986
| title = Insp Rept 50-344/86-06 on 860128-30 & 0224-28.Deviation Noted Re Control Room Emergency Ventilation Sys
| author name = Driscoll J, Hayes J, Willett D, Young T
| author affiliation = NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
| addressee name =
| addressee affiliation =
| docket = 05000344
| license number =
| contact person =
| document report number = 50-344-86-06, 50-344-86-6, TAC-60941, TAC-61289, NUDOCS 8604070301
| package number = ML20141C697
| document type = INSPECTION REPORT, NRC-GENERATED, INSPECTION REPORT, UTILITY, TEXT-INSPECTION & AUDIT & I&E CIRCULARS
| page count = 9
}}
See also: [[see also::IR 05000344/1986006]]
 
=Text=
{{#Wiki_filter:. .
  .
                                        .
                                                          *t
                                                            .
'
                                                                                        i
                            U.-S. NUCLEAR REGULATORY COMMISSION
                                          REGION V
    Report No.                50-344/86-06
    Docket No.                50-344
    License No.                NPF-1
    Licensee:                  Portland General Electric Company,
                              121 S. W. Salmon Street
                              Portland, Oregon 97204
    Facility Name:            Trojan Nuclear Plant
    Inspection at:            Rainier, Oregon
    Inspection conducted:      January 28-30, and February 24-28, 1986
    Inspectors:        Oh
                M .'Willett, P actor Inspector
                                                                      3- 7/- M
                                                                      Date Signed
                                [
                              .Y h h
                    J. Hay g, Engineer, ERR Plant Systems
                                                                      % 21 e9 S
                                                                      Date Signed
                    D N MM [
                    J. I)(1scoll, Contractfgineer
                                                                      3 2/-Jr 6 .
                                                                      Date. Signed
                    Argonne National Laboratory
    Approved By:                //b            f-                    3 - y i - f (,
                    T. Ypnk, Jr. , Chief', Engineering Section        Date Signed
    Summary:
    Inspection during the period of January 28-30, and February 24-28, 1986
    (Report No. 50-344/86-06)
    Areas Inspected: Special announced inspection of control room emergency
    ventilation system.
    Resuloc: In the one area inspected one deviation and three unresolved items
    were ide ntified. 'Other enforcement action related to this inspection will be
    the subject of separate correspondence.
                                                        -
        9604070301
                ADOCK O
                      860    344
          PDR                PDR
          O
                                                      n        ,
                                                -
                                    ,
                                            .
                                  F          6
                                                              7
                                              o      .  -      -                    ,
                                                                    ,
                                                    ,
 
  ,      .              .                                    .  , . . .          .-__ __    _ _ - _ _ - - _ _ _ _ _
      '
    .
-.
                                                    DETAILS
        1.      Persons Contacted
                  Licensee                                                                                                '
                ' Skip Orser, Plant Manager
'
          x*+fGary Zimmerman, Manager, Licensing
        *x*+fRobert Rupe, Secondary Plant Engineer
          x*+@ Henry Goldmann, Mechanical Plant Engineer
              + Bob Schmitt, Manager, Plant Operations and Maintenance
            *x+Al Cohlmeyer, Plant Engineering Supervisor
              + Dick Bennett, Electrical Supervisor
!-      *x*+ Scott Bauer, Onsite Licensing Engineer
l        x*+f@ William Kershul, Licensing Engineer
              $xRich Russell, Assistant Supervisor, Operations
]              $ Bud Susee, Operations Supervisor
                  NRC                                                                                                      ,
              $Jan Norris, NRR
I            $ Jim Milhoan, NRR
4              $Phil McKee, IE
l-            $ Dennis Kirsch, Director, Division of Reactor Safety & Projects, RV
j              $Tolbert Young, Chief, Engineering Section, RV
!            $ Robert Dodds, Chief, Reactor Projects Section 1,107
,'      $*x*+#@ Jack Hayes, Engineer, NRR Plant Systems Section
        $*x*+f@ John Driscoll, Contract Engineer)'Argonne National Laboratory
        $*x*+#@ Dennis Willett, Reactor Inspector, Region V, Engineering
              fKen Johnston, Trojan Project Manager, NRR
'
              $fTed Quay, Plant Systems Chief,'NRR
;                Steve Varga, PWR Project Director No.3, Nlui
              * Denotes those present for January 28, 1986 meeting at Trojan Site.
i
              + Denotes those present for January 29, 1986 meeting at Trojan Site.
              # Denotes those present for January 30, 1986 meeting at PGE, Portland
                Corporate Offices.
;
              @ Denotes those present for surveillance test on January 28-29, 1986 at the-
                                                                '
                Trojan Site.
              xDenotes those present for February 24, 1986 Entrance meetingaat the site
                and Corporate facilities.
              ' Denotes those present for February 27, 1986 Exit meeting at the Trojan
                Site.
                $ Denotes those present for February 28, 1986 teleconference in Region V.
.
                                                                                            , ,                        ,.
                  . ~ . .  , ,  y        --~ - -,. -w      .-          -
 
                                                                  _
                                                                                                ,
                                                    +g
    -
                                                                                              .
  .
                                        '
                                                  .                ,
                              U.-S.    NUCLEAR. REGULATORY COMMISSION
                                              REGION V
      Report No.                50-344/86-06
      Docket No.                50-344
      License No.                NPF-1
      Licensee:                  Portland General Electric Company
                                121 S. W. Salmon Street
                                Portland, Oregon 97204
      Facility Name:            Trojan Nuclear Plant
      Inspection at:            Rainier, Oregon
      Inspection conducted:      January 28-30, and February 24-28, 1986
      Inspectors:        Mo.m.4                                              3 - 7/- fr 6
                  M Willett,            actor Inspector                        Date Signed
                                .Y h h
                      J. Haye,4 Engineer, WStR Plant Systems
                                                                              3- 2 /-8~ l
                                                                              Date Signed
                      b.                                                    ~3 ~~f/~e9 & .
                      J.I)(iscoll,Contractfgineer                              Date Signed
                      Argonne National Laboratory
      Approved By:    h            8                    f--                    3 * J / - 8(
                      T. Ypng, Jr. , Chief', Engineering Section              Date Signed
      Surunary:
      Inspection during the period of January 28-30, and February 24-28, 1986
      (Report No. 50-344/86-06)
                                                                                                  1
      Areas Inspected: Special announced inspection of control room emergency                      1
      ventilation system.
      Results: In the one area inspected one deviation and three unresolved items
      were identified. Other enforcement action related to this inspection will be
      the subject of separate correspondence.
                                                                                                  I
          Pa*
            o
                  !as Pe%*                                                                  ,
.
                                    -
                                                            ...          ,
                                      !
                                                        4
                                            t    i                    F
                                                                +
                          _                    i J                    .  .
 
    '
  .
1
                                              DETAILS
      1.    Persons Contacted
              Licensee
            ' Skip Orser, Plant Manager
        x*+fGary Zimmerman, Manager, Licensing
      *x*+# Robert Rupe, Secondary Plant Engineer
        x*+@ Henry Goldmann, Mechanical Plant Engineer
            + Bob Schmitt, Manager, Plant Operations and Maintenance
          *x+Al Cohlmeyer, Plant Engineering Supervisor
            + Dick Bennett, Electrical Supervisor
        *x*+ Scott Bauer, Onsite Licensing Engineer
      x*+#@ William Kershul, Licensing Engineer
l
          $xRich Russell, Assistant Supervisor, Operations
          .$ Bud Susee, Operations Supervisor
              NRC
't
            $Jan Norris, NRR
            $ Jim Milhoan, NRR
            $Phil McKee, IE
            $ Dennis Kirsch, Director, Division of Reactor Safety & Projects, RV
            $Tolbert Young, Chief, Engineering.Section, RV
            $ Robert Dodds, Chief, Reactor Projects Section 1, RV
      $*x*+#@ Jack Hayes, Engineer, NRR Plant Systems Section
      $*x*+f@ John Driscoll, Contract Engineer, Argonne National Laboratory
      $*x*+f@ Dennis Willett, Reactor Inspector, Region V, Engineering
            fKen Johnston, Trojan Project Manager, NRR
          $$Ted Quay, Plant Systems Chief, NRR
            Steve Varga, PWR Project Director No.3, ENRR
i          * Denotes those present for January 28, 1986 meeting at Trojan Site.
.l          + Denotes those present for January 29, 1986 meeting at Trojan Site.
l          # Denotes those present for January 30, 1986 meeting at PGE, Portland
            Corporate Offices.
'
            @ Denotes those present for surveillance test on January 28-29, 1986 at the
            Trojan Site.
            xDenotes those present for February 24, 1986 Entrance meeting at the site
I          and Corporate facilities.
            * Denotes those present for February 27, 1986 Exit meeting at the Trojan
            Site.
            $ Denotes those present for February 28, 1986 teleconference in Region V.
.
 
        .                        .                                          .
    '
  ,
                                                2
      2.-  Emergency Ventilation Survey
          The inspectors met with licensee representatives (January 28, 1986),
          identified in paragraph 1, to discuss the NRR program for inspecting a
,          large sample of nuclear plant control room emergency ventilation systems
          and evaluating the adequacy of these systems as designed and built by a
          wide variety _of vendors, architects, and constructors.      In addition to an
          evaluation of the licensee's request to modify the technical
                                                    3
          specifications to make Specification 4.7.6.1 an annual, instead of
          monthly, test, this inspection is an extension of the program submitted
          by NRR and IE to the EDO in response'to ACRS concerns: (Control Room
          Habitability Working Group Report, June 1984 ) "...that the NRC STAFF's
          goal for confirming compliance with existing Regulatory Guides and
          Standard Review plan for TMI item III.D.3.4 Control Room Habitability may
          not be adequate to protect the control room occupants from radiation,
          particularly with respect to leakage control and arrangement of air
          intakes...."
          The inspectors observed the conduct of the monthly surveillance test
          (POT-20-1, Rev.16) for control room emergpacy ventilation system
          (4.7.6.1) at the start of, the midnight to 8:00 a.m. shif t (January 29,
          1986). The inspector's purpose was to take independent measurements of
          temperature and humidity at select locations during the ten hour
          surveillance period and chart these changes to determine the adequacy of
          the emergency ventilation system with the. normal ventilation system
          secured.
          During the conduct of the test the inspectors noted several
          inconsistencies between how the test was being performed and the
          licensee's submittals, FSAR, Technical Specifications, TMI III.D.3.4
          response (January 2,1981), SSER (October 1974), ANSI-N510-1975, and
          Regulatory Guide 1.52. In addition, the inspectors identified that the
          test was not being performed in a manner consistent with how the system
          would be lined up and operated during emergency operation. This is an
          apparent violation (86-06-01). After a short time into the surveillance
          the inspectors terminated their involvement since, in their opinion, the
          surveillance procedure was inadequate and the way the test was being
          conducted could not provide any useful information. The following
          narrative identifies how the system was aligned and operated during the
          conduct of the surveillance test.
          The normal ventilation system CB-2 was secured. The emergency
          Ventilation system CB-1 was initiated. Dampers 1051 A & B were closed,
          these dampers supply outside make-up air (150 cfm) to the heaters and
          charcoal filters. CB-4 & 3, the bathroom vent and laboratory exhaust
          fume hood vents and fans, were open and operating exhausting (their
'
          capacity is 4050 and 3740 cfm respectively) out of the control room
          envelcpe. The humidity control for the charcoal heaters was adjusted up
          from its current setpoint of 85 to 100%, which means that the heaters
          would remain off for any humidity of less than 100%. The inspectors
          informed the test engineers and shift manager that a differential
          pressure gauge'(outside air relative to the control room), on the back
          wall of the control room, was registering off-scale negative indicating
                            -
                                .  . -.  -                        .                -  --
 
  L<                              r
                                              , ,
                                                          a                        4t                            -  i
                                                              v              o
                                                                  _
                                          e1,
        -                                                                                                  .
                                                                        ,              .
  .
                              ,                        3                                .                .
                                            4
                                              y          .r                ,
                                                                                        ,
                                                                                                              ,
                                                    .w
                                                        (
                                                        '
                                                                                            w            .a
                                                                                        '
                                                f              sr-                              ,,
                                                                                                      ,
            -that the; control' room was atfainegative, pressure with respect.to the
              outside.                        '-      ,
                                                                        ,
                                                                                      '*    '
                                                                                                    _
          .                                                                      ,y                ~
              The Technical' Specifications l4.7.6.1 states that,''?Each control room .                                i
              ventilation system shall.be, demonstrated operable".                                      _
                                                                                                                        '
              a.    At least once per 31 days,on a STAGGERED TEST BASIS by initiating
                    .-flow through the HEPA filter and charcoal adsorber train and
                    verifying that the train operates for~at least 10 hours with'the
                    preheaters on and maintains.the control room temperature (110'F.
              The BASES for this Technical' Specification states'in 3/4.7.6:                                            '
                    "The OPERABILITY of the control room ventilation system ensures'that                              i
                    1) the ambient air temperature does'not' exceed the allowable
                                                                          '
                    temperature for continuous duty rating for-the equipment and
                    instrumentation cooled by this system, and 2) the control room will
                    remain habitable for operations personnel during and following all                                i
                    credible accident conditions. The OPERABILITY of this. system in
                    conjunction with control room design provisions is -based on limiting '
                    the radiation exposure to personnel occupying the control room to 5
                    REM or less whole body, or its equivalent. This limitation is
                    consistent with the requirements of General Design Criteria 19 of
                    Appendix  "A", 10 CFR 50."-
              The Safety Evaluation Report October'1974 states, in section 6.4
              "
                ...Under emergency conditions 150 cfm of filtered pressurized air is
                                                                                                                        .
              provided to assure a positive pressure inside the control room to limit
              the amount of unfiltered air leakage into the' control room." The                                      '
              calculated radiation doses to control room personnel following a LOCA to
              satisfy General Design Criteria 19, Appendix "A" 10 CFR 50, appear to                                    ,
              rely upon the positive pressure and. filtered make-up' air features.
              The' updated FSAR in section 6.4.2.3 states that, "The control room
              ventilation system is' designed'to maintain a 1/8-in. water gauge
                                                                                                            ~
              differential pressure with one train of EVS (CB-1)Loperating. A control                                    ,
              room volume of 81,300 cu ft (section 12.2.2.3) and a make-up ventilation                                  -
              flow rate of 150 cfm result in net air leakage rate of 0.11 hr-1 "(The
              preceding is also reiterated in PGE's submittal for_III.D.3.4, Withers to
                                                                                                                        .
                                                                                                                        ;
              Eisenhut, January 2, 1981). "... Low leakage dampers are used to isolate-                                  '
              the control room emergency zone from adjacent zones and the outside.
              Figure 9.4-1 of the FSAR shows the locations of these dampers. The                                          :
              dampers are designed for a leakage rate of 41 percent, not to exceed                                        )
              50 cfa." '?...Section6.4.4.1.2statesthat7"anupdatedcontrolroom                                              j
              radiation analysis has been performed' utilizing the assumptions outlined
              in Nuclear Power Plant Control Room Ventilation System for Meeting
              General Design Criteria 19" by Murphy'and Campe.                              (This document is
              identified in NUREG-0737 as guidance for satisfying TMI item'III.D.3.4
              Control Room Habitability Requirements). The updated analysis uses
              150 cfm filtered makeup with 10 cfm unfiltered ingress / egress.
            ' FSAR section 9.4.1.2 System description states, '?...The duct work is
,            arranged to supply 150 cfm of outdoor makeup air and to recirculate                                .
              enough air to provide a total flow of 3200)cfm when one system is
                                                                  r.            ;
                                                  ,
                                                  ;                    ;
                                                                                >-            ,
                                        "                                            "
.    ,.
                                                    f'      __
                                                                    k
                                                                            ,    , ,
 
                                    . - .
                                                              - -. .-- ,    ---. -.___ _ -
    ,
                                                                                                ,
      .
*
                                                4
            operating. Low' leakage dampers'are provided which can close off the
            supply of outdoor air...."    This section also goes on to say, "...The low
            leakage dampers-in the outdoor air' supply to system CB-1 are normally
            closed and require manual actuation to open...." The inspectors were
        <
            informed that there were no instructions in any of the emergency
                                                            2
            procedures which. instructed'the operators to open these outside air
            dampers. Additionally, the. inspectors were told that following a Safety
            Injection signal no makelup air is' admitted for 8 hours (FSAR Section              *
  s        12.3.3.2.3).-                      ,  - i. - ~i i            .
                                                                                              ~
            The system description. continues, "... Controls in the electric preheat
            coils in; system CB-1:are arranged to'en'able;them to. carry out their
            design. function which is.co prevent.. air;from entering the filter trains
                                                                          .
            at relative humidity' higher.than 90 percent. . If/a humidistat in the
            entering air stream shows more than 70-percent relative humidity and flow
            switch' establishes that there,is airflow, the preheat coil will be
            energized. .It has the capacity.co r reduce the relative humidity.of the
            incoming air frta from'100 percentLto 70 percent...."                              !
                                  '
          Theinspectorsmetwith\lic'enseerepresentatives(January 29, 1986),
            identified in paragraph <1,-to discuss the following concerns:
            1.    The preheaters were not'on as per technical specification
                  requirements. This is an. unresolved item (86-06-02).-
            2.    The outside makeup air 4amperg.were closed which would not allow any
                  positive pressure control with leakage., This is an apparent              .
                violation (86-06-03).
            3.    CB-3 And 4 were not secured which exhausted enough air to make the
                  control room pressure negative relative to the outside, this is an
                  apparent violation (86-06-04).
          4.    The humidistat was not set as per submittal to NRC. This is an
                  apparent deviation (86-06-05).
          5.    No instruction in the emergency procedures directing operators to
                open.the make up dampers when emergency ventilation was required.
          6.    The control room envelope differential pressure measurements should.
                be relative to the highest' adjacent boundaries relative to the                !
                control room' envelope. This is an apparent violation (86-06-06)
          Th'e licensee stated that they would review these issues and the
          circumstances.
          The inspectors met with licensee representatives (January 30, 1986),                  ;
          identified in paragraph 1, to discuss the above concerns. At this time                ;
          . the inspectors also held a separate teleconference with NRR Project                  l
          Management and Flant Systems Management.-                                            l
                                                                                                l
          The licensee had not been able to determine why the humidistats were set              !
          to 85 percent for normal operation when they should have.been set to
                                                                                                1
                                                                                                l
                                                              ,
                                                                                                J
 
                      -_      -                      _    _                  -
                                                                                y
                                      .
  '
I                                        15                                      )
                                                                                  l
    70 percent (70% is consistent with ANSI /ASME N509-1980 section 5.5.1 and
    Regulatory Guide 1.52).
    The licensee has agreed to do the surveillance test with the humidistats
    set to 70 parcent, the makeup dampers.open, the bathroom and lab fume
    hood exhaust (CB-4 & 3) secured. The licensee questions the validity of
    the Technical Specification which states that the train operates for
    10 hours with the preheaters on and maintains the control room at < 110*F.
    The licensee contends that with the humidstats set at 70 percent
    (automatic) that this is equivalent to "0N". The NRR project management
    and Plant systems management take exception to this interpretation and
    concur that for the test, the humidstats should be set at zero percent
    which would energize the heaters.
    The inspectors discussed with the licensee staff, the prudence of
    measuring the control room differential pressure relative to the highest
    control room boundary, instead of the outside atmosphere, since it is
    possible that one of the boundaries could be at a higher pressure than
    outside. The licensee committed to measure differential pressure at the
    six boundaries for this determination.
    The inspectors met with licensee representatives on February 24, 1986, at
    the site and the corporate office. The inspectors stated that, based on
    preliminary findings of the previous inspection, the purpose of this
*
    return inspection was to obtain additional assurances that the emergency
    ventilation system satisfies GDC-19. The inspector expressed the region's
    concerns and told the licensee that regional management expected the
    licensee to provide an analysis to support their position that the
    emergency ventilation system had, in past and current configurations,
    met GDC-19. This analysis should also contain some data to support the
    assumptions and conclusions (basic data would be relevant air flows and
    balances during normal and emergency configurations).
    The inspectors discussed with the system engineer and his supervision
    what line flow data would be necessary to make an adequate determination
    of system performance. The system engineer and inspectors walked the
    systems down to find where flow measurements could be taken, from
    existing test ports, and to determine the most appropriate point to make
    measurements on lines without instrumentation ports. From this walkdown
    the inspectors expressed an additional concern, regardin8 the accuracy of
    the licensee's data on system performance and design for surveillance
    since many of these lines did not have instrumentation ports to obtain
    the necessary minimum data. This is an apparent violation (86-06-07).
    Licensee representatives initiated maintenance requests and enlisted
    engineering support to install test ports in portions of the normal and
    emergency ventilation systems where data would be required to support
    analysis of ventilation system performance.
                                                  -
                                      . -
 
  .
*
                                        6
    The inspectors evaluated the suitability of potential test port locations
    for adequacy and the potential to obtain reliable representative
    readings.
    Upon installation of test ports, the inspectors, with calibrated NRC
    instruments, took data during operation of the normal ventilation system
    and with the emergency ventilation system "0N", while the makeup dampers
    were open and closed, and CB-3 & 4 was in different combinations of 0FF
    and ON. During these measurements it was discovered that the makeup flow
    rate from CB-1B was approximately 460 cfm when it should be a design 150
    cfm. This is an apparent violation (86-06-08). The inspectors
    terminated their data taking until the licensee could adjust the "B"
    system makeup ficw to appropriate values and the "A" train could be
    measured.
    Af ter the licensee had adjusted the CB-1 makeup flow to approximately
    190 cfm, and was running the monthly 10 hour surveillance test, the
    inspectors took another set of data. During these measurements the
    inspectors discovered that a two inch drain pipe for the cooling units,
    on the downstream side of the filter /adsorbers, was sucking air into CB-1
    A & B trains. The inspectors measured approximately 41 cfm flow
    (equivalent to approximately 800 cfm filtered flow with a 95 % filter
    adsorber efficiency). The drain pipe was connected to both    "A" and "B"
    trains with a common outlet (configuration similar to a Y). This
    configuration should have been identified during required visual
    inspections of the emergency ventilation system per ANSI-N510-1975. This
    is an apparent violation (86-06-09). This configuration conotituted a
    common mode failure and a lack of train separation, so the licensee
    capped the common line. This new configuration allowed CB-1 A & B trains
    to draw makeup from both make up lines at the same time and the system
    still lacked train separation. This is an apparent violation (86-06-10).
    The licensee initiated steps to have the lines cut and drain valves
    installed.
    During the period that the licensee was responding to the drain pipe
    issue, and while the inspectors were continuing to take data, the
    inspectors discovered that fan CB-3 was still operating. This fan was
    required to be off during the surveillance test. The licensee discovered
    that, although the indication in the control room indicated that the fan
    was OFF, the indication in the control room was really for the damper
    position on the discharge of fan CB-1 and not the fan. When the
    discharge damper for fan CB-1 is closed it operates a limit switch which
    is suppose to cut off power to the fan. The licensee determined that the
    limit switch and damper positioning needed to be adjusted relative to
    each other.
    The inspectors terminated their measurements until the licensee could
    solve the system problems, place the system in the appropriate
    configuration and complete the system surveillances. The inspectors met
    with the plant manager and representatives of his staff, identified in
    paragraph 1 on February 27 to discuss their concerns and findings. The
    licensee told the inspectors that they were not staffed or instrumented
    to deal with the above questions of system performance, and would acquire
 
    *
  .
                                              7
        additional resources to assure that these systems were adequate and would
        be operated in a manner that would satisfy their intent.
        After inspector discussions with regional and NRR management, several
        concerns were forwarded to the licensee in a confirmatory action letter,
        dated February 28, 1986 (J. Martin to B. Withers). The licensee responded
        to the confirmatory action letter March 4,1986 (B. Withers to J Martin).
        Based on an evaluation of the findings of this inspection and previous
        licensee submittals, Region V has requested that NRR determine if the
        emergency ventilation system satisfied General Design Criteria 19
          (Appendix "A" to 10 CFR) in past and present configurations. This is an
        unresolved item (86-06-11).
        During operation of the. emergency ventilation system (CB-1) with the
        normal control room ventilation system (CB-2) secured, approximately
        600 cfm of flow was measured in the normal makeup air duct. An
        additional, 150 cfm of flow was measured in the control room exhaust
          (CB-12). The direction of flow in these two measurements could not be
,        determined with the available instruments. If the direction of flow was
i
        out, this would mean that the control room must-be at a negative pressure
        relative to the outside because there was approximately 300 cfm more of
        exit flow than there is of make up flow.
l
        The control room is required to be at least a positive 1/8 inch water
        gauge differential with respect.to the surrounding boundaries. One
                                            -
        possible explanation of why the pressure was being measured positive is
        the location of the pressure sensing device taps in the duct work. The
        pressure differential is being measured between the control room and
        inside of the normal ventilation system supply duct. This means that the
        pressure gauge is configured so that the low side is connected to the
        supply duct and the high side is open to the control room atmosphere.    If
        600 cfm of air is exiting this duct this implies that the duct is at a
        higher pressure than the outside atmosphere and would cause that gauge to
        indicate a lower than actual differential pressure.
l        If the direction of air flow is "IN", the duct pressure is lower than
        atmosphere, causing the gauge to indicate that the differential pressure
        is higher than actually exists between the control room and outside
        atmosphere. This could account for how the control room could be
        maintained at a positive pressure with the emergency makeup dampers
        closed. If the leakage is "IN" the estimated thyroid dose, as calculated
        by NRR, could possibly be in excess of 900 rem.
        Either case is unacceptable because the control room is either operating
        at a negative pressure or seeing excessive unfiltered makeup flow. This
        is an unresolved item (86-06-12).
      3. Reporting of Events (10 CFR 50.72)
        During a review of procedures and documents associated with the emergency
        ventilation system, the inspectors reviewed the October 7, 1981, meeting
        minutes of the Plant Review Board (PRB). The meeting minutes identified
        that PGE personnel had not performed the monthly surveillance
 
                                                                                                                                                                                                  . - - _ _ _ - - _ - _ _ _
                                                                                                                                                                                                                              -
    *
  .
                                                                                                                                                                            8
                                                                              s                                                                                                  ,
                                                                    '                                                                                                          ^
          requirenents for control room habitabi11ty ((110F') between August 22,
          1979, and September 18, 1981 (over'two years). .The PRB concluded that:
          since the system was capable of maintaining the control room temperature
          at 6 110F* on September.1981,,that-the system had been adequate during
          the previous tworyears,~and that this constituted a missed surveillance
          and was not reportable. This is an apparent violation of reporting
          requirements contained in Amendment 21 of the Technical Specifications
2        (86-06-13)'.>                                                                                                                    .                        ., ,    .
      4. Unresolved-Items                                                                                                                                          *    .
                                                                                                                                                                          ~
          Unresolved items are matters about.which more information is required in
          order to ascertain whether they are acceptable items, violations or
          deviations. Unresolved items disclosed during the inspection are
          discussed in paragraph 2.
;    5. Exit Interview
4
'
          The inspectors met with representatives (denoted in paragraph 1) on
          January 30, and February 27, 1986. The scope and findings of the
          inspection, which were discussed during the exit interview are set forth
,
          in paragraphs 1 through 4 of this report.
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