ML20055F562
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| ML20055F562 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 06/25/1990 |
| From: | Conte R, Florek D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20055F561 | List: |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-1.C.1, TASK-1.C.9, TASK-TM 50-352-90-80, 50-353-90-80, GL-82-33, NUDOCS 9007180028 | |
| Download: ML20055F562 (30) | |
See also: IR 05000352/1990080
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, JUL 0 31990
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U.S. NUCLEAR REGULATORY COMMISSION
g REGION-I.
LIMERICK GENERATING STATION
TRANSIENT RESPONSE IMPLEMENTING PLAN.(TRIP) PROCEDURE INSPECTION:
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Combined Report No.:- 30-352/90-80 and 50-353/90-80
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j Facility Docket No.: 60-352 and 50-353
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Facility License No.: NPF-39.and NPF-85
Licensee: ' Philadelphia Electric Csmpany.
Nuclear-Group Headqua'ters
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. Correspondence Control Desk
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P.-0. Box 195
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Wayne,_PA' 19087-0195
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Facil'ty
i Name: Limerick Generating Station Units 1 -and 2
, -ilnspection At:- Limerick, Pa
, =~ Inspection Conducted: May 21_- 25, 1990
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. Team Members: G. Bethke, System Specialist, COMEX
T. Easlick, Operations Engineer, Region I
S. Hanson,-Operations Engineer, Region I
B.'._Paramore,-Human. Factor Specialist, SAIC
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L. Scholl, Limerick Resident Inspector
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Team. Leader: c l' M /"b "
Donald J. Florg SP' Operations Engineer / Datf
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' Approved'By: W '7d
Richard J. Con g/ Chief, BWR Section Date
Operations Brahfh, DRS
Inspection Summary: Inspection on May 21-25, 1990 (Combined Inspection Report
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~Nos. 50-352/90-80 and 50-353/90-86)
Areas-Inspected: Special announced inspection of the Limerick Generating
Station (LGS) Transient Response Implementing Plan (TRIP) procedures to include
a comparison of the TRIP procedures with the LGS plant specific technical
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' guidelines (PSTG) and the BWR owners group emergency: procedure guidelines-(EPG)
revision ~4,--review of the technical adequacy'of tne deviations from the_EPG,
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control room and. plant walkdowns of the TRIP procedures, real-time evaluation-
of.the TRIP procedures onLthe-plant simulator, evaluation of Lthe licensee
program'on continuing improvement of the TRIP procedures,-performance of human ,.
: factor analysis of the TRIP procedures, Quality Assurance involvement in the "
TRIP development process, non licensed operator training on TRIP. procedures and
review of the mode' switch issue pertaining to the TRIP procedures,
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Results: See Executive Summary in report.
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EXECUTIVE SUMMARY:
The inspection concluded the Limerick Generating Station TRIP procedures are
technically acceptable, that the TRIP procedures can be physica'ly carried out
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.in the plant and the operators can implemsnt the-TRIP procedure;. However,
some findings are identified,
b The technical adequacy review idercified that, in general, the. TRIP procedures
-are considered to be technically adequate and the TRIP procedures and PSTG for
Limerick Generating-Stations are consistent with the BWR Owners Group EPGs.
There are a- few differences between the PSTG and the procedures that require
license'e action. (Unresolved item 352 and 353/90-80-01, Section 4).
. Based on the walkdowns -(section 5), the glare from the plexiglass covering the
flowcharts lin.the control room is excessive. The glare makes it-difficult-to
use the procedures. The T-200. series procedures are greatly improved since the
last review by NRC inspectors during the requalification examination in January
1990. The intensive revision effort conducted over the past 4 months, combined
-with the validation and verification process, has resulted in procedures with
very few identified deficiencies. Based on the walkdown results, the NRC
inspection' team concluded that the LGS TRIP procedures are able to be performed
in the control room and in the plant. (Closed unresolved items 352 and 353/
90-01-01 from requalification examination report)
The simulator (Section 6) observation reinforced many of the team's human
factors concerns with regard-to the TRIP procedure. However, in spite;of the
complexity of the steps'and the size of the TRIP procedures the operators are
able to implement them effectively and demonstrated a thorough understanding
of the TRIP procedures.
Revision'of the SPDS to agree with the revised TRIP procedures will. occur.in
-mid-July, 1990. Currently SPDS is not used in the simulat'or because it is not
yet functional. Once functional in the simulator, the method to integrate SPDS
with TRIP procedure usage will be established. During the simulator scenarios,
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the lack of 'a functional SPDS in the simulator did not hamper the operators
from utilizing the TRIP procedures.
In- the human factor review (section 7), the inspection team concluded that,
with some exceptions, the administrative procedure for control of the TRIP
procedures provides adequate guidance and covers the major topics that should
.be addressed.in procedure preparation guidelines. Some omissions and needs for
enhancement of the existing guidance are identified.
Optitive chbrattaristics of the TRIP flowcharts included correct use of
' cautions and notes, incorporation of cautions into the flowpath, and exclusion
of' action instructions from both cautions and notes. Tables and graphs are
well positioned and linked to the steps to-which they apply. Logic statemcnts
are, with minor exceptions, written correctly.
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There were two principal human factors concerns about the TRIP flowcharts:
size.and complexity. T-101 and T-102 are inconvenient to use because of their
dimensions. The si:e of the flowcharts is related to the wording of the step
-instructions. Steps are frequently long and complex. In addition, a number of
steps are redundant and others provide no useful information to the operators.
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-To a large extent,-these problems result from incorporating the language of the
.BWR Owners Group Emergency Procedure Guidelines (EPGs) essentially verbatim
:into the TRIP flowcharts. The EPGs were not written to meet the criteria for
Lthe clarity and brevity that are applicable to procedure' step writing. The
human factor concerns-are unresolved item 352 and 353/90-80-02.
The inspection team evaluated (section 8) the ongoing procedures program and
concluded that LGS has established an appropriate program for incorporating
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input from operational' and training experience; for maintaining the integration
of emergency procedures, design, and technical criteria; and for maintaining
consistent.and usable format, structure and style of the emergency operating
procedures.
~As_ described in section 9 the LGS Quality Assurance department has been and
' continues to be involved in the TRIP program.
Non-licensed operators occasionally had difficulty in locating infrequer,tly
operated valves during the walkdown of the T-200 series procedures. The NRC
inspection team-attempted to determine _the reason for the difficulty in finding
these valves.- A review of the non-licensed operator training was condtcted
(section 10). No specific cause for the non-licensed operator difficulty in
locating infrequently operated T-200 series procedure valves could be
determined.
The = Verification and Validation program of T-200 series-proceduresL(Section 11)
has been-generally effective in identifying the majority of problems with new
LTRIP revisions.and in insuring that they are corrected.before the procedures
are approved by the Plant Operations Review Committee (PORC).
:In section 12,_the NRC staff concluded that the licensee actions to resolve-
the mode switch issue for'the_ TRIP procedures are adequate,
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DETAILS
, :1.'0L Background
Following the Three Mile Island (TMI) accident the Office of Nuclear-
Reactor Regulation developed the "TMI Action Plan" (NUREG-0660 and NUREG-
0737) which required licensees of operating reactors to reanalyze transi -
enta and accidents and to upgrade emergency operating procedures (EOPs)-
(Item I.C.1). The plan also required the NRC staff to develop a long-
term plan that integrated and expanded efforts in the writing, reviewing,
and nonitoring of plant procedures (Item I.C 9). NUREG-0899, " Guidelines
for the Preparation of Emergency Operating Procedures," represents the
NRC staf f's_ long-term program for upgrading E0Ps, and describes the use-
of a Procedure Generation Package" (PGP) to prepare E0Ps. The licensees -
formed four vendor type owner groups corresponding to the four major
reactor types in the United States, Working with General Electric and
the NRC, the Boiling Water Reactor % ners Group (BWROG) developed the BWR
Emergency Procedure Guidelines (EPGs) which are generic procedures that
set forth the desired BWR accident mitigation strategy. The EPGs were to-
be used by the licensees in developing their PGP. Submittal of.the PGP
was made a requirement by Generic Letter.82-33, " Supplement 1.to NUREG-
0737, Requirements for Emergency Response Capability." The generic
letter requires each-licensee to submit a PGP which includes:
(i)' Plant-specific: technical guidelines
(ii) A writers guide
(iii) A description of the program to.be used for the validation of E0Ps
(iv).A description of_the training program for the upgraded E0Ps
From.this PGP, plant specific E0Ps were to have been developed that-would
provide the operator with'the directions to mitigate the consequences of.
a broad range of accidents and multiple equipment failures.
Due to various circumstances, there were long delays in achieving NRC
approval of many of the PGPs. Nevertheless, the licensees have imple-
mented their E0Ps. To determine the success of the implementation, a
series of NRC inspections were conducted in 1988 which; examined the final
product of the program, the E0Ps. The results of the NRC inspections
conducted during 1988 were summarized in NUREG-1358, " Lessons Learned
from the Special Inspection Program for Emergency Operating Procedures."
This inspection is a continuing effort of the NRC to evaluate the E0Ps.at
licensee facilities.
On May 21 - 25, 1990, an NRC team of inspectors consisting of two NRC
operations engineers, a reactor system consultant, a human factor specialist
and the re'sident inspector conducted an inspection of the Transient Response
Implementing Plan (TRIP) Procedures at the Limerick Generating Station
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(LGS) UnitsL1 and 2. LGS is a BWR 4 with a Mark II containment. structure.
The~ objectives of the inspection'were to determine if: the TRIP procedures
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are: technically correct; the TRIP procedures can be physically carried-out ,
in'the plant; and that the TRIP procedures can be performed by the plant '
. staff =
.The objectives.would be considered to be m'et if review of the following
. areas-were found.to be adequate: comparison of the TRIP procedures with
the LGS plant specific technical guidelines (PSTG) and the BWR owners
group emergency procedure guidelines (EPG);> review of the technical
adequacy of the deviations from the EPG;. control room and plant walkdowns
of the TRIP procedures; real time evaluation of the TRIP procedures'on the ,
plant simulator; evaluation of the licensee program on continuing improve- l
ment of the TRIP procedures; and performance of human factor analysis <of- I
the TRIP procedures. The inspection focused on the adequacy of the end-- 1
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product, the TRIP procedures and did not depend on the review of the l
process to develop the procedures. If any of the areas were not found to "
be acceptable,- the inspection would assess other areas as necessary to
understand the basis.for the deficiencies.
2.0 Pbrsons-Contacted .
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- Limerick Generating Station l
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V, Cwietniewicz, Superintendent Training l
G. Edwards,' Superintendent Technical 1
~L. Hopki.ns,'. Superintendent Operations
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*J. Hutton,;0perations Support Engineer
'*G. Leitch, Vice-President Limerick j.
*R. Nunez,10perations Training Supervisor j
*R.-Shoff,1 System Engineer !
*R. Smith,.NQA Auditor. -!
*K. Walsh .Sr. Engineer,' Technical
The inspectors also contacted other members of the licensee operation and -
: technical staff.
-Pa Department of Environmental Resources / Bureau of Radiation Protection
*A. Bhattacharyya, Nuclear Engineer
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-U; S. Nuclear Regulatory Commission
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*T. Kenny, Senior: Resident Inspector
*D. Florek, Sr. Operations Engineer
=*G Bethke, NRC Censultant - Comex
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*B Paramore, NRC Consultant - SAIC
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*L. Scholl, Resident Inspector
'* Denotes those present at the exit meeting conducted on May 25, 1990. *
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3.0 Basic TRIP /BWR Owners Group EPG Comparison
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A comparison of the TRIP procedures and-the BWR Owners Group Emergency
' Procedure-Guidelines (BWR EPGs), Revision 4, was conducted to ensure that
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the licensee had procedures as' indicated in the EPGs, The procedures-
reviewed are listed in Attachment A of this report.
The facility procedures are in agreement with the BWR EPGs on the type
y of procedures required to respond to symptoms which result in entry into
these procedures.
14.0 Independent Technical Adequacy Review of the TRIP Procedures
The Limerick Generating _ Station procedures in Attachment A were reviewed
to assure that the procedures are technically. adequate and accurately
incorporate the BWR Owner's Group EPGs, A comparison between the Plant
Specific-Technical Guidelines (PSTG) to the EPG and TRIPS was also
performed. Differences between the EPG and PSTG were assessed for adequ-
ate technical' justification. Selected specific values from the procedures
were reviewed to determine that the values were correct.
In general,'the. TRIP procedures are considered to be technically adequate
and the_ TRIP procedures and PSTG for Limerick Generating Stations are
consistent-with the BWR Owners Group EPGs. The selected specific values
from the' procedures were determined to be correct. The inspection team
) identified a few items in the procedures and PSTG that require additional
licensee action.
. Specifically, when transitioning to the contingency portion of-the PSTG,
the PSTG refers to specific procedures numbers, such as the T-100 series,
rather than the individual PSTG contingencies. As indicated by the
licensee, the basis for this is that the T-100 series procedure is the
procedure that the contingency is based on. This was not always the case
in the procedures. Referring to the contingency, rather than the specific
procedure in-the PSTG, allows more flexibility in;providing human factored
procedures. Discrepancies were identified between the PSTG and the proce-
dures'as a result of this methodology. In most instances, the procedures
were determined'to be correct and the PSTG was. determined to require modi-
fication. An example is Procedure RPV Control T-101, RC/L-2 which directs-
entry into Emergency Blowdown, T-112, for a condition where level is un-
known. The PSTG directs entry into RPV Flooding, T-116 under that condi-
. tion,_ While technically there is no problem with the procedure sequence,
since.T-112 directs entry into T-116, consistency would alleviate the
if possible confusion between the guidelines and the procedures.
The inspectors identified a TRIP procedure deviation from the PSTG on entry
.into;RPV Control which constitutes extra steps that may not be required
and has the potential to cause operator error. In many cases (e.g. Primary
Containment Control), the PSTG directs a manual scram and entry into the
RPV control guideline. The TRIP procedures direct entry into T-100, the
scram procedere, not RPV control. However, T-100 does not contain the
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same accident mitigation = strategy as does RPV control. T-100~does contain-
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a step:that if an entry condition exists for T-101, the operator is-directed-
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to exit T-100 and enter T-101.
A related deviation was identified.regarding the PSTG direction when
y' . emergency RPV depressurization is required, to enter T-101'at Step RC-1
, and execute it concurrently. The TRIP procedures only direct entry-into.
T-112, Emergency Blowdown. The licensee indicateo that procedure T-112-
, ,, has direction to' scram the reactor if it has not already been scrammed,
,therefore, entry into T-101 is redundant. The inspection team concluded
that since T-101 gives-the operator guidance to control level and power
that the T-112 does not, T-101 should be entered when emergency blowdown
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.is required.-
There were several examples of incorrect information in the PSTG that
reflect on system capability. The PSTG refers to the steam condensing
mode of;RHR, HPCI use for boron injection, LPCI loops C and 0 heat ex-
changer capability and RPV flooding sources none of which exist in the
plant.
There are several actions contained in the TRIP procedures which are.not
directed by the PSTGs, These include establishing suppression pool cool- +
ing without consideration of adequate _ core cooling when an SRV is cycling-
in T-101 RPV_. control, not emergency depressurizing below 100 psig unless
motor-driven pumps are-available and inclusion of technical specification
actions in the-SP/T portion of T-102. The Primary Containment Control
. procedure, T-102 Step SP/L-10 through SP/L-17 gives guidance on actions to
A ~be taken when_ suppression pool level exceeds 17 feet. The-licensee was
unable-to provide adequate rationale in its technical basis' document for
[, ,c these' actions.
A number of the ' transition points were in error. 'In T-101 the entry from -
T-99.is PSR-9 not PSR-8. In T-99 the entry from T-101 is RC/P-18 not
RC/P-15. In T-118 entry frcm T-117 should be LQ-27 rather than LQ-25.
Human factor comments in se: tion 7 address the need for such transition
point's.
The licensee's flow charts incorporate terminology which require some
additional. clarification. Definition of certain terms which are intended-
Eto direct an operator through the flow charts such as: " stabilize,"'
" shutdown;" and " consider," are ambiguous and are open to interpretation
R by the operators. These terms require concise definitions that are-
clearly understood by the operators.
The RPV Control-procedure, T-101 step RC/P-4, directs an operator to hold
,, at this step until " power is below 4?o." The PSTG requires that the opera-
tor determine if the reactor is " shutdown" at this point. The phrase
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" power is below 4?s," is not the correct determination for a shutdown
reactor.
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The Piimary Containment Control procedure, T-102 steps SP/L-22 and SP/T--
14, condition depressurization if boron injection is required. The PSTG
requires depressurization regardless of whether_ boron injection is
required.
The Primary Containment' Control procedure,-T-102, step SP/L-8 has a note
which-states that at 17.8 feet suppression pool ~ level, the SPOTMOS temper-
ature indication becomes invalid. The note does not direct.the operator to -
use'an alternate indication,-in this case RHR pump suction. temperature
indication with an RHR pump in service.
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The Emergency Blowdown procedure, T-112, steps EB-1, EB-2 and EB-3,
require the ooerator'to scram the reactor and enter the Scram procedure,
T-100. This action is considered by the inspection team to be a' redundant
step-since all entry conditions but one,-T-102, DW/T, already direct the'
reactor be scrammed prior to entering.T-112. The licensee-is considering
placing the: scram direction in T-102, DW/T and removing it from.the T-112
procedure. Step EB-19 directs securing HPCI on high suppression pool
level. This is also considered to be redundant due to this guidance
appearing in T-102.
The' north and south stack process radiation monitor HI-HI alarm setpoints,
used as entry conditions into the T-104 procedure, are conservative with
respect to the EPG entry condition requirement of " release rate above the
offsite release rate which requires an Alert." The T-104 entry conditions
are satisfactory with respect to monitored releases, but do not directly
. address the unmonitored release path scenario. The facility representa-
tive agreed to evaluate adding the ALERT (Radiological) step from their
Emergency Plan Classification procedure (EP-101) as an entry condition to;
LT-104, and adding-reference to T-104 in the respective section of
EP-101'.
-The licensee actionseto resolve the above noted technical adequacy s
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, concerns are considered to be unresolved items (352/90-80-01 and 353/90-
80-01),
5.0 Control Room and Plant Walkdowns
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The inspectors walked down the TRIP procedures and procedures referenced
therein to confirm that- the procedures- can be implemented. The purpose of
the walkdowns was to verify that instruments and controls contained or
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required to be used to implement the procedures are consistent with the
_ installed plant equipment, ensure that the indicators, controls, annunci-
ators : referenced in the procedures are available to the operator, and
ensure that1the task can tre accomplished. Detailed comments identified
care noted in Attachment B. General comments, observations and conclusions
from the detailed comments are discussed below.
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During the.NRC.requalification examinations administered during the week:
m of January 29,-1990 the NRC identified deficiencies in the T-200 series ,
procedures. The adequacy of the T-200 series procedures was considered-
-to be unresolved items 352 and 353/90-01-01. Overall, the T-200 series
-procedures were greatly improved since the last review by NRC inspectors.
The-intensive revision effort conducted over the past 4 months, combined'
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with the validation and verification process,-has resulted in procedures
with very few identified deficiencies.- Based on the walkdown results, the'
NRC inspection-team concluded that the LGS TRIP procedures are able to be
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performed in the control room and in the plant, ' LGS demonstrated an
extremely cooperative and aggressive attitude in correcting problems
identified during the inspection, with most.of the identified deficiencies
;immediately corrected by the licensee. As a result of the licensee'. .
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efforts and the licensee plans to further review the T-200 procedures that'
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the NRC inspection-team did not walkdown to identify and correct, if any, !
the' type of findings that the _NRC inspection team identified, unresolved
items 352 and 353/90-01-01 are considered to_be closed. ;
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The glare from the_. plexiglass covering the flowcharts in the. control room o
is excessive. The glare makes it difficult to use the procedures. Due to
t ifferent lighting patterns in the simulator, the glare from the flow- ;
charts in the simulator is much less pronounced.
The NRC inspection team identified that the non-licensed operators
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occasionally had difficulty in locating infrequently operated T-200 series '
procedure valves. -_ As a result non-license operator use of TRIP: procedures
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: was further _as'sessed -(see section 10).
6~ 0: Simulator
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Six scenarios were conducted on the plant specific simulator using two
shift crews. The simulator scenarios provided information on real time
activities. 'The purposes of the simulator scenarios were.to~ determine ,
that the TRIP procedures provide operators _with sufficient guidance such ,
that their responsibilities and required actions during emergencies both. ,;
11ndividually and as a team are clearly outlined; verify that the.proce- ~
'dures do not cause: operators.to physically interfere with each other while ;
performing-the TRIP procedures and verify that the procedures did not '
duplicate operator actions unless required (i.e. independent verifica-
tion). -In addition, when-a transition from one TRIP procedure to another- ;
procedure is required, precautions are taken to ensure that all necessary '
; steps, prerequisites, and initial conditions are met or completed and that-
the operators are knowledgeable about where to enter and exit the '
procedure. 1
Through-observation during the scenario the team concluded that the TRIP
rrocedures do not cause operators to physically interfere with each other.
;nd operator actions are not duplicated. When a transition from one TRIP
procedure to another is required, the team concluded that the operators 4
enter and exit the procedures at the correct point and ensure conditions
are met _before doing so.
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.The simulator observations reinforced the tesm's human factors concerns
with regard to the TRIP procedure. However, in spite of the complexity
.of the steps and the size of the TRIP procederes the operators are able-
to= implement _them effecth oly and demonstrated a thorough understanding.
of the TRIP procedures,
One of the comments noted during the-plant walkdown was that the curves
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on SPDS-in the plant do not agree with the curves in the TRIP procedures,
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, . SPDS-was not used by; operators in the simulator because it is not yet
E functional in the simulator; The inspection team questiorgd.the1 facility
on how SPDS interfaces _with TRIP procedure usage, -The current location of-
the SPDS monitors is not conducive for use by the shift supervisor while"
using the TRIP procedures. The SPDS monitors are located on the shift
supervisors desk and.the reactor operaters computer desk. The TRIP
procedures are.used by the shift _ supervisor on the back of the reactor
operators computer desk, Neither monitor is visible to the shift supervisor.
The facility will establish SPDS/ TRIP procedure interfaces during simulater
training after SPDS becomas functional in the simulator, During the-
: simulator scenarios the lack of a functional SPDS in the simulator did not
hamper the operators from utilizing the TRIP procedures.
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7,0 Human Factors Review of the E0Ps
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The human factors review included (1) evaluation of the licensee's written:
guidance-for the preparation of the TRIP procedures; (2) comparison of
that guidance to the procedures; and (3) general evaluation of the proce-
dures with reference to principles of procedural information presentation.
'in the applicable NUREGs- (5228, 0899, and 1358). Discrepancies identified-
in this review ~were evaluated for operational impact during the walkdowns
and simulator exercises.
7.1. Evaluation of TRIP Preparation Guidance (Writer's Guide)
The guidance for preparation of TRIP procedures is contained in
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administrative-procedure A-94, Rev. 5. This document addresses
-preparation of_the Plant-Specific Technical. Guidelines-(PSTG):
preparation of the PSTG-to-flowchart conversion documentation;
preparation of TRIP bases documentation; preparation of flowchart and
satellite procedures; and the verification and validation program.
The inspection team concluded that, with some exceptions, A-94
provides adequate-guidance and covers the major topics that should
be addressed in procedure preparation guidelines. Omissions and.needs-
for enhancement of the existing guidance are identified in Attachment
C.
The licensee is currently preparing new procedures (NA-11T001,
NG-001, and NG-002) that will control ongoing preparation / revision of
TRIP procedures at both Limerick and Peach Bottom. Licensee repre-
sentatives stated that the new procedures will incorporate the guid-
ance now in A-94 and will supersede A-94. LGS personnel also stated
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that the Attachment'C items pertaining to A-94 will be addressed-
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during the preparation of the new administrative: control and guidance .
. documents.for theLTRIP procedures program. !
n 27.2 Comparison of Writer's Guide to the TRIP Procedures-
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b The inspection team found that'the guidance provided in A-94, Revi--
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sion 5, was consistently implemented in the TRIP flowcharts.. A-94, ,
Revision 5 provides minimum guidance for preparation'of TRIP satell ' ;
r ite-procedures (T-200 series), but the applicable guidance was t
n implementeo.
p 7.3' General Human Facters Evaluation of the TRIP Procedures
Positive characteristics of the TRIP flowcharts included correct use 1
of cautions and notes, incorporation of cautions into the flowpath,
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and' exclusion of action instructions from both-cautions and notes. '
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Tables and graphs are well positioned and l_ inked to the: steps to
<which-they' apply by dashed lines. .The' usab111ty of graphs is en- a
hanced by delineation and color coding to distinguish safe and unsafe '
zones.. Logic statements are, with minor exceptions, written
correctly (despite the lack of guidance on this topic in A-94). i
There were two principal human factors concerns about the TRIP flow- '2
charts: size and complexity. T-101 and T-102 are inconvenient to
-
cuse because of their dimensions. Those two procedures are'likely'to
be;used concurrently in an emergency event, and.other procedures may
~
also be needed at the.same time. T-101'is close'to4 feet vertically l
and overhangs the' top of'the layout table. T-102 is more'than 7. feet-
horizontal.ly. .0perators identified the size of T-102, in particular,- ,
,
as a problem,. although they stated that it is usable.
It was observed in the simulator exercises that..the control room- 3
supervisors were able to use multiple procedures ef.fectively despite :
~'
.dif ficulties related to their size. In the simulator, however,Rit is
possible to lay down T-101 and T-102. side by side, which.is not possible ;
.given the flowchart laydown space in the' control room. Simulator i
training ~ activities area expected to use the same space allocation 1
! - for TRIP use as is available in the control room.' !
t
~The size of the flowcharts is related to the wording of the step
: instructions. Steps are frequently too long and complex. There are
.
i
numerous " recheck. steps" written as conditional logic statements. ;
_.. . The recheck steps include unnecessary phrases that describe step
- applicability (e.g., "while executing RC/P"). In addition, a number 1
of steps .were identified that could be omitted; some are redundant
and others provide'no-useful information to the operators. To a ;
large extent, these problems result from incorporating the language
ofi he
t generic Emergency Procedure Guidelines (EPGs) essentially '
verbatim into the TRIP flowcharts. The EPGs were not written to meet
I
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, . !
,
L *
c. .
'
1 9+ ,
-
13
'
3 ,
the criteria .for the clarity and brevity that are applicable to
procedure step writing. Examples of the characteristics that-make. r
the TRIP flowcharts unnecessarily complex are provided in Attachment
C.
Licensee actions to-resolve the human factor concerns are considered to
be unresolved items. (352/90-80-02 and 353/90-80-02)
.
j
8,0 On-going Evaluation of E0Ps
t
The inspection team determined if the licensee has established a=long-term
evaluation program for emergency operating procedures as recommended in t
Section 6.2.3 ofsNUREG-0899. The LGS program was reviewed to ensure that .
it provides for: input from operational experience and use; input from
-training-experience; established methods for keeping the emergency proce-
dures consistent with changes in plant design, technical specifications,
other operating criteria, generic and plant-specific technical . guidelines, +
writer'.s guide, and other plant procedures;-periodic review and a clearly-
- def.ined; adequate process for revisions, including verification and vali-
.dation;;and appropriate training. :
o
.The inspection team evaluated the ongoing procedures program at LGS ,
, through-interviews and review of controlled documents, verification and
.
validation' documentation, and training documentation. The inspection team _ ,
'
concluded that LGS has established an appropriate program for incorporat-
ing input from operational.and training experience; for maintaining the= ,
. integration of' emergency procedures, design,. and. technical criteria; and
'for maintaining consistent and usable format, structure and style of the
emergency operating procedures.
9.0 QA' Measures
'
The NRC team inspected the QA organization involvement in the programmatic !
app' roach of-the TRIP program. The inspection focused on those policies, ,
.e
procedures and instructions necessary to provide a planned and periodic
'
. audit of the TRIP ~ procedures development' and~ implementation process.
, The inspector interviewed the LGS -QA inspector responsible for auJits of-
the operations department. The QA inspector.was very knowledgearle of q
the- history, applicable requirements, and status of TRIP procedure at
. Limerick. .
:The last QA audit covering the TRIP procedures was reviewed. The last
audit encompassed _ operations department procedures in addition to TRIP
l procedures, evaluated the conversion of the GE Revision 4 EPGS to PSTG ,
to TRIP Flowcharts, but did not include a review of the T-200 series
procedures. The portion of the audit dealing with TRIPS included all of
the applicable references to NUREGs, Technical Specifications, NRC
Inspection Reports, INPO Good Practices, and internal LGS Administrative
procedures for development of the essential elements to be audited. The
. _ _ _ _ _ - _ - .
, .
'
.. ..
..
4 -14
.
audit resulted in Corrective Action Requests (CARS) and recommendations
which have been implemented by the operations department.- l
The QA Department has developed a new module in their Master Audit Plan
which separates the audit of-TRIPS into a stand alone audit designated
MAP 0.8 (versus being part of a broader operations audit). The NRC
inspector verified that audits of TRIP procedures are scheduled for the
upcoming year.
= In summary- the LGS Quality Assurance department.has been- and continues
to be involved in the TRIP program,
g1
10.0 Non-licensed operator use of TRIP procedures .-
As described in Attachment B non-licensed operators occasionally had .I
difficulty in locating infrequently operated valves during the walkdown
-of the T-200-series procedures. The NRC inspection team attempted to
determine the reason for the difficulty in finding these valves. A review i
=of the non-licensed. operator training was-conducted. The revi_ew. included i
o content and frequency of non-licensed operator T-200 series training and
instructor lesson plans for training.
Non-licensed operator training on the Limerick T-200 series procedures was
initially conducted 'in April 1988.
j
Training for all Limerick non-licensed 1
operators for the-recent revision changes was conducted in Apr_il.1990.
The training included both classroom and plant walkdowns of all the T-200 'ii
series procedures. T-200 series _ procedure training for non-licensed
operators is not conducted on a periodic or re-occurring basis. 1
No specific cause for the-non-licensed operator difficulty in locating _ 'l
infrequently-operated T-200 series procedure valves could be determined. '
The inspection. team identified three possible contributors: the non-
licensed training program may not have been effective during the walkdown
phase, some of the procedures lacked noun name descriptions for valves
.which would help key operators to the valve function and therefore its
j
tphysical location with respect to major components and posting'of area-
maps, many of which were missing as noted in Attachment C. ;
11.0 Verification and Validation (V & V) of T-200 Series Procedures -1
1
The inspectors reviewed the results of the V&V conducted on_ the most
recent revision of:the T-200 series procedures and found'that every'sub-
stantive discrepancy identified by the V&V Team had been included in the ,
approved version of the procedures. Documentation for the V&V process was [
readily available and easily audited. '
i'
The. Verification and Validation program of T-200 series. procedures has
been generally effective in identifying the majority of problems with new
TRIP revisions and in insuring that they are corrected before the proce-
dures are approved by the Plant Operations Review Committee (PORC).
.
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M 112.0 Mode Switch Issue- t
During:a facility ' simulator exercise at the Limerick training center, the
facility identified a scenario which resulted in a_ potential RPV high,
~
water. level and high pressure condition- The sequence of events for this
,
.
Itransient can:be summarized by the following:
1. Main Turbine EHC pressure. regulator. fails high, fully opening nine '
(9) turbine bypass valves.
.
w i
..
"
, 2. ' Rapid increase-in RPV steam flow results'in a depressurization of -!
the RPV and a water level swell.
3. .RPV water level reaches level 8, causing' a trip of the main turbine
.stop valves, feedwater turbine, and HPCI/RCIC turbines. !
4
4
4. Main Turbine stop valve closur.e causes a reactor scram.
,
, ,
+ - 5 '. : Operator places the mode-switch to shutdown before the MSIV's auto- '
matically close on low steam lire. pressure.
,
6. -The' level. decreases to'the initiation-setpoint of HPCI and RCIC which i
sufficiently mitigates the level decrease, preventing a level 1 J
.
closure of the MSIV's.
p
# ,7. RPV pressure decreases below the condensate pump shutoff head and
;thesel pumps begin to inject into the RPV eventuallyLfilling'the RPV.- ',
above--the main. steam lines.-
s
18. . Condensate flow into,the'RPV is terminated and~the MSIV's'are manu-
> +
ally closed'with a high level and low pressure existing in the
. reactor. <
9. RPV level will swell and presture' increases due to the warming of the ,
, reactor inventory by' decay heat. s
'
.,
=Two concerns were generated with regard to placing the mode switch in
shutdown'which bypasses the low pressure MSIV isolation for this type of ;
"
.
an event. The first was a potential for RPV overfill .and the second was
:potentially exceeding depressurization/cooldown rates. These' concerns
. prompted the Nuclear. Engineering Division (NED) to submit a Justification 4
4 .
.forcContinued Operation .(JCO) 'L-90-050-001, for the Limerick Generating !
'
-
' Station;(LGS), dated February 2,1990, valid for three (3) months. This "
provided sufficient time to resolve the issues identified in the simulator
exercise.
,
The inspector reviewed the resolution of the JC0 for LGS Units.1 and 2, .
and Peach Bottom Atomic Power Stations Units 2 and 3, and the basis for I
suspending the'JC0, dated April 30, 1990. Also reviewed was a supplement '
to the above letter, dated May 8,1990, which clarified safety / economic ,
concerns raised by PORC on May 1,1990,
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The licensee concluded that based on the design analysis, although RPV
overfill-or stresses in excess of. those allowed for Anticipated Opera-
fL -tional Transients may be expertenced, neither is a significant safety .
concern.- For either situation, the consequences do not approach the
t severity of the currently bounding Design Basis Accident. Allowable
stress as permitted by the FSAR for the equipment such as-the RPV and SRV
-discharge line may be exceeded,;but'the overall-integrity of the Reactor
-
Coolant Pressure Boundary is expected to be maintained.
g
^dditionally, the licensee concluded that for the EHC pressure regulator.
failure 'open direction event, with the addition of more specific oper-'
ator guidance, procedura1' actions are sufficient to avoid the consequences j
of an excessive cooldown or vessel overfill. The licensee plans to
'
prov_ide additional operator procedural guidance and training. The develop-
ment of a new Off-Normal (0N) procedure for inadvertent reactor depressur- {
, ization is also being considered by the licensee. FSAR changes will be-
-prepared _by NED to be implemented into the 1991 FSAR update.
The NRC staff concluded that the resolution of the JC0 and the follow-up l
. actions are adequate. i
13.0 Licensee Action on Previous Inspection Finding
8
<
As> indicated in Section 5.0, the inspector reviewed the licensee actions
in response to unresolved items 352 and 353/90-01-01. The licensee-
actions were considered acceptable, and unresolved items 352 and'353/
f5 -90-01-01 are considered to be' closed.
;
14.0 IUnresolved Iterr
Unresolved ite . are matters about which more information is required to q
ascertain.whether:they are acceptable items, items of' noncompliance or ;
deviations. Unresolved items ' identified during the inspection are l
discussed in' sections'4 and 7. 1
15.0 Exit 1nterview
~
] i
d
'
'At the conclusion of th'e inspection on May 25, 1990, an exit meeting was !
conducted with those persons indicated in paragraph 2. The inspection l
scope'and findings were summarized. The licensee did not identify as
'proprietaryj any of _the-materials- provided to or reviewed by the inspectors
]
l
;during the inspection. j
The facility actions to respond to the inspection findings are summarized j
as follows. The_-licensee took immediate corrective act?on to resolve most I
rof the-items identified during '.he walkthrough of the procedures in the- 3
. control, room and the plant during the inspection. The licensee verbally
, indicated that by July 15, 1990, the licensee will correct the PSTG and TRIP
-flowchart errors _and by December 31, 1990, the licensee will astess-the i
general writers guide issues and flowchart complexity issues anc identify ,
L additional actions, j l, j
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ATTACHMENT A
f
DOCUMENTS REVIEWED
L
!
Flowchart TRIP procedures * denotes those procedures walked down !
o i,
, T-99 .' Common Post Scram Restoration, Rev 5 :
T-100 Common Scram, Rev 5 '
*T-101 Common RPV Control, Rev 6
,
r
i s
*T-102 Common Containment Control, Rev 6
.
*T-103 Common Secondary Containment Control, Rev 4 *
h.
*T-104 Common Radioactivity Release Control. Rev 4 -
N *T-111 Common Level Restoration, Rev 5 N *T-112= Common Emergency Blowdown, Rev 5 ;
*T-116' Common RPV Flooding, Rev 5 ;
'
.
*T-117 Common Level / Power Control, 9ev 5 *
'*T-118 CommonLPrimary Containment Flooding, Rev 1
. ;
Other TRIP p ocedures '
<
*T-200 Unit 1 Primary Containment Emergency Vent, Rev 6 l
:J .T-200 Unit 2 Primary Containment Emergency Vent, Rev 4 >
'
N 'ti-209. Unit l'RCIC Boron Injection from SLC tank, Rev 3 i
T-209 . Unit 2 RCIC Boron Injection from SLC tank, Rev 3
.
i
T-210 Unit 1 CRD Boron-Injection from SLC tank, Rev.7 [
,g *T-210. Unit 2 CRD Boron Injection from SLC tank, Rev 4 :
'T-211 Unit 1 CRD System Boric Acid Injection,.Rev 4' !
*T-211 Unit 2 CRD System Boric Acid Injection, Rev 3
-
'
*T-212' Unit 1 RWCU SLC Injection, Rev 8
T-212 Unit 2 RWCU SLC Injection, Rev 4 "
J
-T-213:-Unit 1 Individual--Control Rod Scram / Solenoid De-energization, Rev 4 I
. ,
T-213 Unit 2 Individual Control Rod Scram / Solenoid De-energization, Rev 1
V -T-214 Unit 1 Manual Initiation of ARI, Rev 6
T-214 Unit 2 Manual Initiation of ARI, Rev 4
us
'
'
T-215 Unit 1 De-energization of Scram Solenoids, Rev 5 i
-T-215. Unit 2-De-energization of Scram Solenoids, Rev 3
g
'
'
*T-216. Unit-1 Manual Isolation and Vent of-Scram Air Header, Rev 4
T-216 Unit 2- Manual Isolation and Vent of Scram Air Header, Rev 2
t
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!
T-217 Unit 1 Backup Method of Venting / Draining Scram Discharge
i
'
Volume, Rev 3
, 'T-217 Unit 2 Backup Method of Venting / Draining Scram Discharge
Volume, Rev 3
i
l T-218 Unit 1 Control Rod Insertion by kithdraw Line Venting, Rev 2 ,
'
F 'T-218 Unit 2 Control: Rod Insertion by Withdraw Line Venting, Rev 2 ,
4
*T-221 Unit 1 MSIV Low Low Low Level Bypass, Rev 11
o *T-221 Unit 2 MSIV Low Low Low Level Bypass, Rev 4
*T-222 Unit-1 RPS/ARI Reset, Rev 2
*T-222 Unit 2 RPS/ARI Reset, Rev 2
*T-225 Unit 1 Containment' Spray Interlock Bypass, Rev 7 .
*T-225 Unit 2 Contair, ment Spray Interlock Bypass, Rev 5
'
.
,
'
T-226 Unit 1 Using RWCU as Alternative Method for Decey Heat
Removal, Rev 2
<
*T-226 Unit 2 Using RWCU as Alternative Method for Decay Heat
Removal, Rev 3 .
;
,
-
'T-227 Unit 1. Bypass of Reactor Enclosure HVAC High Drywell
Pressure / Low RPV Water Level Isolation, Rev 7 '
T-227 Unit 2 Bypass of Reactor Enclosure HVAC High Drywell
g Pressure / Low RPV Water' Level Isolation, Rev 6
,
'T-228 Unit 1 Purging Primary Containment, Rev 3 :
'T-228 Unit 2 Purging Primary Containment, Rey 2 *
.
*T-230 Unit'1 Suppression pool to CST by way or HPCI or RCIC, Rev 7
T-230 Unit 2~ Suppression pool to CST by way cf HPCI or RCIC, Rev 4
-T-231 Unit 1 RHR$W B to Suppression Pool, Rev 8 a
*T-231' Unit 2 RHRSW A to Suppression Pool, Rev.3
T-232 Unit 1' Suppression pool cleanup pump isolation bypass, Rev 7 !
T-232 Unit 2 Suppression pool cleanup pump isolation bypass, Rev 4 i
T-233 Unit 3 Dumping Suppression pool inventory to radwaste by way i
of RHR loop A, Rev 7
T-233 Unit 2 Dumping Suppression-pool inventory to radwaste by way
of RHR loop A, Rev 4 ,
*T-234 Unit 1 Makeup to the Suppression pool from CST by way of the
Core Spray Suction piping, Rev 3
T-234 Unit 2 Makeup to the Suppression pool from CST by way of the
Core Spray Suction piping, Rev 2
r
*T-235 Unit 1 Makeup from Condensate Transfer System or Refueling
Water System to Suppression Pool, Rev 5
'
.
_ _ _
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.
:
,
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'
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3
,
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,
' ;
*
*T-235 Unit 2 Makeup from Condensate Transfer System or Refueling
'
[tt Water System to Suppression Poel. Rev 4
0 -T-236 Unit 1 -Transferring Reactor Enclosurr Floor Drain Sump to j
L 1 4 Suppression Pool via the Core Spray S stem, Rev 3
2
3"
F
T-236 Unit 2 Transferring Reactor. Enclosure Floor Drain Sump to
Suppression Pool via the Core Spray System, Rev 2
*T-240 Unit 1 Maximizing CRD Flow After Shutdown During Emergency -
p
".
.
Conditions, Rev 5 1
T-240 Unit 2 Maximizing CR0 Flow After Shutdown During Emergency 5
,
>
Conditions., Rev 5 ,
! ' U
T-241 Unit 1 Alternate Injection from Condensate of Refueling Water ;
Transfer Systems, Rev 9 j
*T-241 Unit 2 Alternate Injection from Condensate of Refueling Water -
Transfer Systems, Rev 4 :
*T-243 Unit 1 Alternate Injection by way of.RHRSW to RHR loop B, Rev 8 I
*T-243 Unit 2 Alternate Injection by way of RHR$W to RHR loop A,- Rev 4
C, .
.
T-244, Unit 1 Alternate Injection from the Fire System, Rev 4 i
*T-244 Unit 2: Alternate Injection from the Fire System, Rev 2 l
!
m *T-245 Unit 1 RPV Flooding from RHR S/D Cooling, Rev 5 ;
,
T-245-Unit 2 RPV Flooding from RHR S/D Cooling, Rev 3 !
a , ,
*T-246 Unit 1 HPCI High Suppression Pool Level Suction Swapover '
& .
Bypass, Rev 2 +
*T-246 Unit 2 HPCI High Suppression Pool Leve1~ Suction ~Swapover l
Dypass, Rev 2 !
i
~
*T-247 Unit 1 RCIC Low Steam Line Pressure Isolation Bypass, Rev 2 <
* T-247 Unit 2 RCIC Low Steam Line Pressure isolation Bypass, Rev 2
-
'T-248 Unit 1 Injection from SLC Test Tank to RPv', Rev 2
T-248 Unit 2 Injection from SLC Test. Tank to RPV, Rev 2-
9
*T-250 Unit 1 Remote. Manual Primary Containment Isolations,' Rev 11 ;)
l -T-250. Unit 2 Remote Manual' Primary Containment Isolations, Rev 2 ,
"
T-251 Unit 1 Establish a HPCI Injection Flow Path via Feedwater or
. Core. Spray, Rev 7 *
T-251 Unit 2. Establish a HPCI Injection Flow Path via Feedwater or !
"
Core Spray, Rev 4-
.
.T-252 Unit 1 Operation of Barrier Block and Vent Valves and- [
Safeguard Piping Fill, Rev 4 ,
'
'*T-252 Unit 2 Operation of- Barrier Block and Vent Valves and ,
-
Safeguard Piping Fill, Rev 3 '
L J s
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.
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T-255 Unit 1 Filling of RPV Reference 1.egs, Rev 1 l
[j, ,
LT-255 Unit' 2 ' Filling of RPV Reference legs, Rev 1 i
<
'
T-260 Unit 1 . Reactor Vossel Venting, Rev 2
b[e, T-260 Unit 2 Reactoa Vessel Venting, Rev 2 ! g<
'
. .
o
L
1- T-290 Unit 7 Instrument Available for T-103, Rev 2 !
, m ,
1
L T-290 Unit 2 Instrument-Available for T-103, Rev 2
-
'
;
'*T-291_ Unit 1 Secondary Containment Temperature Ef feets on . Reactor :
, Level _ Instrumentation, Rev 1 '
._
be
'
~T-291: Unit 2 Secondary Cont (inment Tempera'ture Effects on Reactor - !
j7
, Level. Instrumentation, Rev 1
L4 ' *S41.3.Ai Equalizing Pressure .* cross MSIV, Rev 2 { ki!I *S48.1 B Standby Liquid Control System Manual initiation Rev 6 ![
i
g Administrative Controls. a
:
Plant Specific Technical Guidelines, Rev 4 dated 4/20/90
,
-
- ' ' A-2 Control of- Procedures and Certain Documents, Rev.6 l
A-14 Procedure for Contro! of Plaat Modifications, Rev 9 j
- A-29 Control of Revisions due to License Document-Revisions, Rev 3 i
.
A-50 P' rocedure for. Conduct of Training, Rev 3
A-04 Preparation'of Transiert Response Implementation Plan (TRIP) Procedures,
'
Rev 5 !
i
*
s
OP Manual Chapter 13, Section 13.2 Procedure Problem Identification. System,
'
;
Rev 2' 1
.
E0P Training Material
t
NLOCT-9031 Non-licensed, operators continuing training program T-200-series
procedures
.-t
Calculctions Reviewed l
i
Cold' shutdown boron weight '
'
Primary containne t pressure limit
i
: NPSil ~1imit;for ECCS pumps ' !
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s. ATTACHMENT B i
,
WALKDOWN COMMENTS
g General Comments - .
1. Many of the T-200 series procedures contain sets of steps which insta11'
jumpers or lift leads to bypass interlocks, or override automatic.func-
tions. . Although the purpose of each procedure is explained in section l'.0 :
Purpose. the actions being accomplished by groups of steps within the body. .'
i of the procedure are not always obvious.- Adding descriptive text immedi- i
- " ately before each major set of jumper / lifted lead. steps would be useful to
inform the user what is being accomplished by the steps. (
!
2. Inspectors noted that some of the area maps and signs formerly located at
the tops of stairwells and entrances to areas have fallen down, or are i
missing. This makes it more difficult for operators to locate infrequ- '
ently operated components which are required to be operated in the T-200
series procedures. .
3.! During the walkdowns the non-licensed operators (NL0s) who performed f
walkdowns of T-200 series procedures had occasional difficulty in locating- 3
infrequently operated valves in the plant. .l
2
4. The glare from the plexiglass covering the flowcharts.in the control room ;
is excessive. The glare makes it difficult to use the procedures, Due to i
.different lighting patterns in the simulator, the glare from the flow- I
.. charts in the simulator is much less pronounced.- During the inspection, ;i L the: licensee' attempted several different methods to reduce or eliminate. ' 'H< the glare form the control room. The glare was eliminated when the_
surface of the plexiglass was roughed up with sandpaper. This however L(
'
resulted in some distortion of the flowchart text. The licensee was still '
pursuing use of low glare plexiglass to miaimize or eliminate the glare in
the control room.
,
!
.
!
Specific' procedure comments
1. T-101'RpV Control
;
. Step RC/P-8 of T-101 has the operator open MSIVs to provide a heat sink, I
b using procedure T-221 if necessary. - T-101 did not " Restore Instrument '
Air" after a LOCA signal per procedure SE-10,'nor did T-221 restore -
F instrument air to the outboard MSIVs. LGS added the proper steps to T-221
' prior:to the inspection team departing the site. t
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2. T-102 Primary Containment Control
The T-102 related curves in the Safety Parameter Display System (SPDS)
did not match the current revision of the E0Ps. SPDS does caution the
operators that the curves currently in SPDS are not valid for use with
the TRIP procedures. Prior to the inspection, LGS scheduled to make the
changes to the SPDS curves by July 1990.
Curve PC/P-3 (Pri Cont Press Limit) asks for Drywell Pressure on recorder
PR57 *01 to calculate containment level. The recorder is labelod "Pri
Cont Atm" versus "Drywell Pressure". The licensee agreed to change the
label of the recorder.
.3. T-116 RPV Flooding
On step RF-19 of the flowchart, the operator is directed to check for a
69 PSIG pressure difference between the reactor pressure vessel and the
suppression pool. The RPV pressure instrument has 20 PSIG scale marks
and the SP instrument has 5 PSIG scale marks. A 69 PSIG delta would be
difficult to read. Since the valve is not critical, a round number,
such as 70, may be used in the procedure.
4. .T-200 Primary Containment Emergency Vent Procedure
The T-200 procedure contains sub procedures for all of the various methods
available at Limerick to vent primary containment. All of the methods
result in releasing the vented containment gases directly to the reactor
enclosure. T-200 includes an appendix A which provides concise guidance
on in plant evolutions which must be considered for completion before the
reactor enclosure is made uninhabitable by one of the venting options.
The mafn body of the procedure does not however refer to the appendix
directly before entering the venting options portion of the procedure.
LGS personnel should consider referencing appendix A early in the T-200
procedure. LGS corrected this procedure before the inspection team
departed the site.
5. T-209 Injection from the SLC Storage Tank with RCIC
Step 3.6 should specify " Turn SLC heaters to A and B on" versus the
current direction to " turn heaters on". There is no "On" po31 tion on
the heater switch. LGS corrected this procedure before the inspection
team departed the site.
The hose between-the SLC tank area and the RCIC room must drop three
floors through an open bay equipment hatch. No provisions have been made
to support the hose as it passes over the sharp edge of the equipment
hatch, or to support the weight of the hose over the three story vertical
run. If this procedure were ever implemented, the hose would likely be
crimped at the edge of the equipment hatch, thus preventing flow to the
RCIC suction. LGS corrected this procedure and added an elbow to the hose
before the inspection team departed the site.
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6. T-211 CRD System Boric Acid - Sodium pentaborate Injection
!
The borax and boric acid stored in the locker near the SLC tank would t>e
of little use for filling the CRD pump suction strainer body, as it would ,
need to.be transported down three floors and from the reactor enclosure
building to the turbine building. The locker contains no thermometer as
specified in the procedure. LGS sheuld consider staging the boron
supplies at the CRD pump, or possibly eliminating this procedure, since i
accomplishment would be very inefficient when compared to the other alter- ,
native SLC injection procedures. LGS added a thermometer to the cabinet
prior to the inspection team departing the site. LGS has stated that they
will cancel this procedure during the next revision to the T- 100 series
E0P flowcharts. ;
The location specified in the procedure for the SLC locker in Unit 2 is
actually the Unit 1 SLC locker location. The procedure should be changed *
to show that each unit has a locker. LGS corrected this procedure before
the inspection team departed the site.
7. T-212 RWCV System SLC Injection
The flow sightglass specified to determine that the RWCV demineralizer is
full is located in the return (discharge) line of the demineralizers. The
sightglass is designated FG-45-1-81. The sightglass would show flow indi-
cation well before the demineralizer was filled with boron solution from
the precoat tank. The sightglasses which should have been specified are
the two located in the demineralizer vents (83 A & B). LGS corrected this
procedure before the inspection team departed the site.
The. Jumpers specified in section 4.2.5 of the procedure were apparently
salvaged from a previously configured kit, where the jumpers were >
connected directly to lugs on the back of individual relays. The jumpers ,
still retained paper labels indicating relay terminal numbers versus the s
new terminal strip lug numbers. The set of jumpers were imnroperly sized
to accomplish all of the jumpering specified in the new procedure (some to
'ong, some to short). The set was also one jumper short of the-number
<
necessary to accomplish all of the jumpers in the procedure. A review of
other procedures ~ indicated that this jumper set problem was generic to *
most of the recently revised T-200 series procedures'. LGS personnel
corrected this problem for all T-200 series procedures within 24 hours
af ter the problem was identified by the NRC inspector.
The terminal specified in step 4.2.5.f of the procedure (AAAS-S) was not
color coded with the magenta tape now in use for all T- 200 series jumper -
location banana plugs. LGS corrected this problem before the audit team
, -departed the site.
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, The terminals specified for jumpering in the RWCU demineralizer panel in
L, step 4.2.1 of the procedure were improperly labeled in the procedure,
"
and the diagram of the terminal locations provided in the procedure was
p . unreadable. LGS corrected this procedure before the audit team departed
L the site.
The precoat pump kill switch is equipped with leads'about-20 feet long
and tipped with alligator clips. In order to see the sightglass on the
, demineralizer vents, the operator must stretch the cables on the kill
switch to'their maximum. This would likely result in pulling the
O' alligator clips off the 97 wire at the precoat pump panel switch. LGS
: corrected this problem by specifying that an additional operator would
,
be required to carry out this procedure.
,
8. T-217 Backuj Method of Drainino Scram Discharge Volume
,--
.
4
_The unit 2 west scram discharge volume (SDV) drain hose needed a 90 degree.
elbow installed to facilitate connection to the drain line and routing to
'
the floor drain. LGS-corrected this procedure and added an elbow to the- -
'
>
hose before the audit team departed the site. j
i
9. T-227 Bypass of Reactor Enclosure HVAC High Drywell Pressure / Low RPV
Water Level isolation
l The: text of the procedure. indicates that one of the purposes of steps in
e : the' procedure is to bypass a "High Radiation-isolation signal. This is
.
incorrect and should be eliminated from the procedure. LGS corrected
this procedare before the inspection-team departed the site.
~" ' ' 10. ,T;228 purging Primary Containment
r
m. Three of the-slide gate dampers requiring local operation in section 4.5 '
of this procedure have not been labeled with the characteristic magenta I
, q labels placed on other E0P related valves and components. LGS properly
I
'
labeled all of the dampers prior to the inspection team' departing the
site,
j
11. :T-235 Makeup from Condensate Transfer System of Refueling Water System
to. Suppression pool
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'
LGS uses an asterisk beside elevation identifications in procedures to-
m indicate that a component is located high in the-area. This convention
. helps operators locate' components more casily. The asterisks were missino.
from some component elevations in the unit 2 T-235 procedure.(e.g.,
F Condensate Transfer to HPCI, RCIC & CS Stayfill Velve). LGS corrected the 9 specific problem in procedure T-235 before the inspection team departed
- s the site.
!
Step 4.1.4 of the' unit 1 procedure contained an error for the location j
[ i
of the "RWCU Backwash Receiver Tank Condensate Supply" valve (listed 1
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area.R11 versus the correct RIS). LGS personnel corrected the procedure l
before the. inspection' team departed the site, i
12. 7-240.Maximizino CRD Flow after Shutdown i
.i
, The' T-240 tool and mr.terials kit is actually' stored on the 283 level of j
i; , the reactor enclosure building, versus in the T-200 locker in the control ;
room as-indicated-in paragraph 3.3 of the procedure. LGS corrected this! -i
,s procedure before the inspection team departed-the site, l
13 ,T-241 Alternate Injection from Condensate or Refuelina Water Transfer
.
l
>
f This procedure is intended to accomplish. low pressure injection of conden-' -
satu transfer water through the discharge piping of various ECCS systems'.
."
'Section 4.1.2 directs.the operator to open one or more ECCS system injec- -
tion valves. The steps in section 4.1.3 of the procedure then provide t
r guidance.to the operator to isolate injection system pump discharge valves
S "As Required". The steps in section 4.1.3 are probauly unnecessary,
assuming that ECCS discharge check valves perform; or as a minimum, should !
'oe modified to specify isolating only the discharge valves of the systems
. selected in section 4.1.2.- -LGS-corrected this procedure by eliminating a
step 4.1.3 before the inspection team departed the site.
14. T-250 Remote Manual' Primary Containment Isolations
Walkdown of this procedure identified errars in valve, switch, and compo-
nent nomenclature, both in'the procedure and on the control boards, (
Examples'are provided below:
Drywell Pressure Root Valve (PCIV-A) is mislabeled in the procedure:as
HS-42-2478,- it should be HS-42-247A. LGS corrected this procedure before ,
the inspection team departed the site.
'
'
'Handswitch for SV57-201 also controls SV57-?39, but'is not labeled as such 1
'
, on the control board.
*
The HV-61-212 and HV-61-232 valve numbers are not listed in.the' procedure. .
-LGSicorrected this procedure before the audit team departed the site.
.
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ATTACHMENT C
HUMAN FACTOR EXAMPLES
The following examples are provided to clarify the types of problems identified
in the areas of human factors concerns described in Section 7 of this report.
These examples are not intended to be viewed as an inclusive list of all such
problems found in the LGS TRIP procedures, but rather as a set of limited
examples of the types of inadequacies found through the human factors analysis.
SPECIFIC FINDINGS ON THE TRIP WRITER'S GUIDE (A-94)
1. A-94 provides no guidance for the writing of logic statements. Logic
statements are, for the most part, correctly written in the procedures,
but guidance is n9eded to ensure that this will continue. It was noted
in the procedures that the word "and" is sometimes treated as a logic
term when it is used simply as a conjunction (for example, all instruc- ,
-tions to execute another procedure concurrently). This is a minor item, I
but it might have been avoided if guidance on logic statements were
provided in A-94.
The major concern regarding logic statements in the TRIP procedures is
comple<ity. There are cases in which the logic structure may be correct
but the ' statement .is very difficult to follow because of multiple condi-
tions, complex wording, or both. (See findings related to TRIP proce- 1
dures for examples.) The writer's guide needs to discuss this topic and
provide examphs, 1
2. A-94 doir; et define a very effective way of using color in the flow-
charts. The guidance is appropriate in limiting the number of colors
used for coding, and the basic color choices are acceptable. However,
the guidance says to use color to delineate symbols. Also, the word
" caution" is specified to be printed in red, and the grid lines of the j
unsafe zone of graphs are to be orange. In essence, this amounts.to
using color for outlining, Color used in this way is not reliably i
noticed; color is used most effectively in larger areas or patches. For ;
example, the unsafe zone of a graph would be perceived more immediately =
if the background were orange and the grid lines black. Operators
commented during inte.' views, walkdowns and simulator exercises that they
'are not aware of the colors in the flowcharts.
. '
3. .A-94 does not fully state the conventions for presenting referencing 1
instructions (instructions to execute another procedure concurrently) and
branching instructions (instructions to leave the present procedure or i
branch and go to another procedure). In the fiowcharts, references T-200
procedures are put in command boxes. References to T-100 procedures are
put in special symbols unless the reference is conditional, in which case
it' appears in the recheck atep command symbol. These practices were found
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to be used consistently, but they are not mentioned in A-94. References
( to non-TRIP procedures are not treated as consistently. Sometimes they
j are in the command box and sometimes in the reference symbol. Examples of
~this inconsistency are given in_the findings related to the TRIP proce-
dures. Writer's_ guidance is needed to ensure that consistency is main- ,
tained. Consistent presentation of referencing and branching instructions
E provides cues that help to ensure that transitions will not be missed.
:- 4. A-94 specifies that flow lines will be heavier weight lines than the
flowchart symbols. The difference in line weight is substantial. . This
guidance is -inconsistent with recommended practice (as indicated in NUREG/
R-5228). The licensee's intent is to make the flowpath clear. However,
the effect is to cause the symbols and the instructions they contain to
c fade into the background. This is not considered a major concern, but it
does detract to some extent from optimal readability.
5. A-94 does not provide any guidance on the method of verification; i.e.,
it does not say what will be done to verify a procedure. A-94 also
provides no guidance on how problems identified during verification will
be resolved.
'
6. A-94 does not provide any guidelines for determining when verification is f
required and when validation is required. These decisions are left to the-
discretion of the procedure riter who makes recommendations to the Plant
Operations Review Committee (PORC).
7.- A-94 does not make it completely -1 ar that verification and validation
apply to satellite procedures (T-200 series) as well as to the flowcharts.
Of particular concern is the need to make sure that satellite procedures
are walked down in sufficient detail to make sure that they are accurate,
feasible, and appropriate for the emergency situatior that the in plant
components involved can be readily located; anf that the tools, materials, J
.
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and equipment needed to perform the tasks are ;;1ablo.
SPECIFIC HUMAN FACTORS FINDINGS CW THE TRIP PROCEDURES
The principal human factors concerns about the LGS TRIP procedures have to do
'
with the size and complexity of the flowcharts. Although the inspection found i
that the flowcharts can be used as written, they have characteristics that i
: detract from clarity and ease of use. Examples are provided in this attach- )
ment. -The examples are not exhaustive. They are intended to illustrate the (
types of issues that should be evaluated to simplify the flowcharts.
1. Unnecessary Steps
1
T-101, Steps RC/Q-1 and RC/L-1 are not useful. They do not state any I
criteria for control. -The necessary criteria are in subsequent steps. f
These are " filler" steps that could be omitted. I
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T-101, Step RC/P-4 This is one of five recheck steps in the RC/P LMnch
of T-101. Recheck steps create a memory burden and this one could be
eliminated. It is included to make sure that the operators do not stay in
RC/P if either emergency blowdown or steam cooling is required. It would
be simpler to' add an instruction to exit RC/P at the appropriate places in
T-111 and T-112, which are much less complex procedures than T-101.
Anether example of this is in T-102, Step $P/L-3. j
T-102, Step PC/H-5. This is a recheck step that is written in a very
complicated way. It may be possible ti eliminate this step. Decision ,
steps.PC/H-6 through PC/H-9 state most of the same criteria much more
clearly. If the "yes" path from those decisions were "yes or unknown,"
the condition addressed by Step PC/H-5 would be covered. This is a case
which also illustrates the potential benefit of using a recheck decision l
symbol (sometime called an override decision).
t
T-116, Step RF-20. This step is redundant. Step RF-18 directs the oper-
ators to achieve essentially the same criteria, and Step RF-21 directs the
operators to maintain those criteria.
2. Unnecessary Phrases
Recheck steps include a phrase that specifies the applicability of the
step --'e.g.,4 "while executing SP/T." In the majority of cases, the re-
check step applies to all subsequent steps in the flowchart branch. To
state' this is unnecessary and makes it more difficult to pick out the
parameter that is to be rechecked. Based on operator input in interviews,
walkthroughs, and simulator exercises, the operators do not Say attention -
to these phrases. The information could be provided by excel tion when a
recheck step does not apply to all subsequent steps. .
3. Other Unnecessary Information
.
In addition to the "while executing . . ." phrases in recheck steps, a
'
bracket is provided to the left of the recheck step and the substquent
steps to which it applies. In some cases, there are nested brackets.
Based on interviews, walkdowns, and simulator exercises it was concluded
that the operators do not make use of these brackets. This coding tech-
nique is clearly unnecetsary when a recheck step applies to all subsequent
steps in a branch. It may be useful by exception, but would be redundant ,
to a phrase iadicating limited applicability of a recheck step.
,
LGS provides entry arrows in referenced T-100-series procedures to iden-
tify the procedure and step (in the T-100 series) from which entry was
directed. In most cases, a referenced T-100-series procedure is entered
at Step 1. The operators do not make use of these entry arrows. It is
!
preferable to limit entry arrows to cases when a referenced procedure is
entered somewhere other than Step 1; in that case, the arrow provides a
L useful cue to and check on correct entry. 1
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4. Large Number of Conditional Logic Statements ;
L The TRIP flowcharts contain a large number of condit %nal. logic state-
g
'
ments. It is better to minimize the use of logic st ements in procedure >
, step instructions because they are not as readily. understood as a simple '
B' . imperative statement or question. Often the information can be presented '
L more clearly in decision format. In some cases LGS has done this and in
.others they have not. For example, in T-101, Steps SP/T-16 through 18 are
'
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, very similar in meaning to Step SP/L-10, but the' presentation is differ-
ent.- In the temperature branch a decision format is used; in the level ;
branch a logic statement-is used. The information is easier to grasp ;
immediately in the decision format.
Step SP/L-8 in the preceding example is a recheck step. If. recheck ;
decisions are used, then a special symbol is needed to highlight them. !
,
Step RC-4 in T-101 is an example of a logic statement that could be ;
'
written more simply as a caution. This step advises the operators that, ,
'in the event of a steam leak, qualified instruments must be used to read
pressure and level. Similar information in the RC/0 branch is provided
in a caution (preceding RC/Q-1). .
1
m 5. - Overly Complicated Steps .
)
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'
Step PC/P-15 in T-102 is especially difficult to follow. It uses a
'
."BEFORE.. . . THEN" structure which is a contradiction ~of terms, in
addition, this step contains a reference to a curve and to a satellite
procedure .and two logic statements. This is a case in which too much !
information has been put into one step. Another example of too much. ,
information in one step is PC/P-4 (also in T-102). 1
-6. Awkward Wording
,
'
'The flowchart steps'contain a number of instances'of awkward wording.
-
'
Frequently these are steps which incorporate phrases from the EPGs verba- y
tim -- e.g., " irrespective of whether adequate core cooling is assured." l
Since this is a recurring . phrase, it should be possible to pare it down, j
(For example, it may be enough to say irrespective of adequate core cool- '
ing,ior irrespective of core cooling). Other examples of awkward wording
' include T-102, Step SP/T-4; T-101, Step RC/P-2; and T-112, Step EB-8. j
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