ML20149H996
| ML20149H996 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 07/16/1997 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML20149H989 | List: |
| References | |
| 50-295-97-02, 50-295-97-07, 50-295-97-2, 50-295-97-7, 50-304-97-02, 50-304-97-07, 50-304-97-2, 50-304-97-7, NUDOCS 9707250279 | |
| Download: ML20149H996 (64) | |
See also: IR 05000295/1997002
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U.lS. NUCLEAR REGULATORY COMMISSION
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REGION lli-
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. Docket Nos:
50 295; 50-304
Licori::9 Nos:
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Licensee:
Commonwealth Edison Company
Facility:
. Zion Generating Station
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- Dates:
July 3,1997
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. Meeting Location:
Region Ill Office
801 Warrenville Road -
Lisle, IL 60532-4351
' Type of Meeting:
Predecisional Enforcement Conference
Inspection:
Zion Station
February 6 - April 2,1997
March 12 - April 28,1997
Inspectors:
A. Vegel, Senior Resident inspector
D. Calhoun, Resident inspector
E. Cobey, Resident inspector
M. Bailey, Operator Licensing Examiner, Rill
G. Galletti, Human Factors Branch, NRR
Approved By:
Marc L. Dapas, Chief
Reactor Projects Branch 2
Meetina Summarv
Predecisional Enforc_qment C_gnference on Julv 3,1997
Areas Discussed: Apparent violations identified during the inspections were discussed,
along with the corrective actions taken or planned by the licensee. The apparent violations
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L concerned performance deficiencies exhibited during the reactivity control event on
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February 21,1997, improper removal of reactor coolant system flow instrumentation from
service on February 22,1997, and the reactor vessel voiding event on March 8,1997.
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9707250279 970716
ADOCK 05000295
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Beport Details
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Persons Present at Conference '
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.Gomingnwealth Edison Comoany iComEdl .
' H. Keiser, Chief Nuclear Operating Officer, Comed
T. Maiman, Senior Vice President, Comed
. J. Mueller, Site Vice President, Zion
S. Perry, Site Vice President. Dresden-
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K. Graesser, Site Vice President, Byron
G. Stanley, Site Vice President, Braidwood
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E. Kraf ti Site Vice President, Guad Cities
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W. Subalusky, Site Vice President, LaSalle
D. Sager, Vice President, Generation Support, Comed
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- R. Starkey, Plant General Manager, Zion
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R. O'Connor, Recovery Plan Manager, Zica
R. Zyduck, Site Quality Verification Director, Zion
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T. Luke, Engineering , Manager, Zion
- G. Vanderheyden, Operations Manager, Zion
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L. Kelley,: Acting Training Manager, Zion .
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K. Dickerson, Executive Assistant, Zion
R. Godley, Regulatory Assurance Manager, Zion
D. Farr, Operations Manager, LaSalle
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R. Wegner, Operations Manager, Byron
D. Cooper, Corrective Action Manager, Comed
T. Gierich, Operations Manager, Byron
D. Cook, Operations Manager, Quad Cities
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T. Palanyk, Acting Assistant Shift Operations Supervisor, Dresden .
D. Ferg, Lead Offsite Reviewer, Comed
M. Burns, Acting System Engineering Supervisor, . Zion
M.-Korchynsky, Shif t Manager, Dresden
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B. Kugelbery, Communications Director, Comed
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H Kim, PWR Safety Analysis Supervisor, Comed
J. Lewand, Corporate Licensing, Comed
D. Smith, Nuclear Communications, Comed
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1. Johnson, Licensing Director, Comed
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F. Spangenberg, Regulatory Assurance Manager, Dresden
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L. Holden, Nuclear Licensing Administrator, Comed
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C. Peterson, Regulatory Affairs, Quad Cities
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T. Peterson, Nuclear Licensing Administrator, Quad Cities
G. Wald, Nuclear Communications Administrator, Comed
R. Temple, Comed
- D. Jankins, Law Department, Comed
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!). S. Nuclear Reaulatory Commission
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A. Beach, Regional Administratcs, idll
R. Capra, Director, Projects Division ill-2, NRR
G. Grant, Director, Division of Reactor Projects (DRP), Rill
J. Lieberman, Director, Office of Enforcement (by telecon)
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B. Berson, Regional Counsel, Rill
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M. Ring, Chief, Engineering Branch, Rlli
M. Leach, Chief, Operator Licensing Branch, Rill
M. Dapas, Chief, DRP Branch 2, Ritt
M. Parker, Acting Chief, DRP Branch 2, Rlli
D. Hills, Project Engineer, Rill
A. Vogel, Senior Resident inspector, Rlli
C. Shiraki, Project Manager, NRR
E. Cobey, Resident inspector, Rlli
J. Heller, Enforcement, Rlli
J. Strasma, Public Affairs
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F. Tomczyk, Area Manager, Westinghouse
R. Vollmer, Consultant, Indos Energy Group
M. Wilson, Reporter, WKRS Radio
C. Nicodemos, Reporter, Chicago Sun-Times
P. Kendall, Chicago Tribune
J. Yesinowski Resident Engineer, Illinois Department of Nuclear Safety
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11.
Ergd_qgigjnnal Enforcement Coqf.erencm
A Predecisional Enforcement Conference was held in the NRC Region lil Office on
July 3,1997. This conference was conducted as a result of the findings of two
inspections conducted from February 6 through April 2,1997, and from March 12
through April 28,1997, in which apparent violations of NRC regulations were
identified. Inspection findings were documented in inspection Report
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Nos. 50-295/97002; 50 304/97002 and 50-295/97007; 50-304/97007,
transmitted to the licensee by letters dated June 4 and May 21,1997, respectively.
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The purpose of this conference was to discuss the violations, root causes,
contributing factors, and the licensee's corrective actions.
During the Predecisional Enforcement Conference, the licensee acknowledged most
of the vio!ations. However, the licensee maintained that a failure to report the
reactor vessel voiding event was not a violation of NRC requirements, but that a
voluntary report would have been appropriate. The licensee's presentation included
characterization of each event's safety significance and the status of correctiva
action implementation for each of the events. Copies of the NRC's and the
licensee's handouts are attached to this report.
Attachments: As stated
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ATTACHMENT
NRC HANDOUT
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1he apparent violations discussed in the predecisional enforcon.ent ccetererte are subject to
further review and are subject to change prior to any resulting enformmnt action
1.
10 CFR Part 50, Appendix B Criterion V. " Instructions, Procedures, and
Drawings," requires that activities affecting quality be prescribed by documented
instructions, procedures, or drawings, of a type appropriate to the circumstances
and be accomplished in accordance with these instructions, procedures, or
drawings.
Zion Administrative Procedure (ZAP) ZAP 300-01, " Conduct of
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Operations," Revision 3,Section VI.A, states that the Shift Engineer
SHAll, maintain a broad perspective of operational conditions affectir'g
the safety of the station as a matter of highest priority at all times.
Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
21,1997, while the licensee was performing a Unit 1 shutdown, the Shift
Engineer failed to maintain a broad perspective on operational conditions
affecting safety of the station as a matter of highest priority, in that,
significant control rod manipulations made by the primary Nuclear Station
Operator went unnoticed.
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ZAP 300-01, " Conduct of Operations," Revision 3,Section VI.A, states
that operations personnel SliALL be attentive to the condition of the plant
at all times.
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Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
21,1997, while the licensee was performing a Unit 1 shutdown, the Unit
Supervisor failed to be attentive to the condition of the plant at all times, in
that, significant control rod manipulations made by the primary Nuclear
Station Operator went unnoticed by him.
The cppan,nt violeu orm discussed in the preaeu uunal entonement w ence are subJeCl LO
turt her review co1 arr subject to change pi ior to any result inq onf m ent action
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The apparent violations discussed in the predecisional enforcement conference are subject to
further review and are subject to change prior to any resulting enforcement action
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ZAP 300-01 A, " Control Room Access and Conduct," Revision 4 Section
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Vill.A, requires that Control Room business SHALL be conducted at a
location and in such a manner that neither on-shift licensed personnel
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attentiveness nor the professional atmosphere is compromised.
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Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
21,1997, the presence of an excessively large number of individuals in
the control room and other numerous distractions caused a loud and -
disruptive environment. As a result, licensed personnel attentiveness and
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the professional atmosphere of the control room were compromised.
d.
ZAP 300-01, " Conduct of Operations," Revision 3,Section VI.A, defines
infrequently performed evolutions as evolutions whereby the performance
frequency is greater than annually AND the evolution requires the
coordination of two or more departments or three or more individuals AND
has the potential to adversely affect reactivity control OR core cooling and
required a briefing be conducted prior to the evolution.
Contrary to the above, an activity affecting quality was not accomplished
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in accordance with the applicable procedure. Specifically, on February
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21,1997, the licensee performed an evolution to maintain the reactor at
the point of adding heat - an evolution which had not been performed in
the last 12 months, required the coordination of three or more people, and
had the potential for adversely affecting reactivity control- without
conducting a pre-evolutionar / briefing for this infrequently performed
. evolution.
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ZAP 300-09, " Station Operational Communications," Revision 3, Section
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communication, then the receiver must promptly inform the sender and
ask the sender to repeat or rephrase the message.
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Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
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21,1997, the primary Nuclear Station Operator failed to promptly inform
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the unit supervisor (the sender) that he did not understand the
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communication concerning driving in control rods and ask the unit
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supervisor to repeat or rephrase his message.
tre accarent violations discussed i'1 the riredecisionn) enforcemem mnf erence are sonmct
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. The apparent violations discussed in the predecisional enforcement conference are subject to
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ZAP 300-09, " Station Operational Communications," Revision 3, Section
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Vll.A.3, requires that all operational communications .Sil LL utilize three-
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communication as "The technique of the sender issuing a communication
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' that is repeated back by the receiver of the communication and confirmed
by the sender to be the correct communication."
Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
21,1997, the primary Nuclear Station Operator (the sender) and the Unit
Supervisor (the receiver) failed to use three-way communications, in that,
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after the primary Nuclear Station Operator announced the low rod
insertion limit, the Unit Supervisor did not verbally repeat the alarm and
the primary Nuclear Station Operator did not confirm the communication.
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ZAP 300-01, " Conduct of Operations," Revision 3,Section VI.A,' requires
that all planned reactivity changes are done in a controlled manner, that
the effects of reactivity changes are known and monitored, and that any.
anomalous indication is met with conservative action.
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Contrary to the above, an activity affecting quality was not accomplished
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in accordance with the applicable procedure. Specifically, on February
21,1997, the primary Nuclear Station Operator failed to perform reactivity
changes in a controlled manner by excessively inserting control rods and
then withdrawing control rods.
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ZAP 300-018, " Reactivity Management Guidelines," Revision 1, Section
G.2.c, states that strict reactivity controls are required to minimize the
potential for core damage, and that all plant personnel, particularly
operators, must stop and question unexpected situations involving
reactivity, criticality, power level, or core anomalies.
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Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
21,1997, the primary Nuclear Station Operator failed to utilize strict
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reactivity controls when he did not stop and question unexpected changes -
in reactivity and power level as he continuously inserted control rods. As
a result the primary Nuclear Station Operator made the reactor
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substantially sub-critical and then attempted to retum the reactor to the
point of adding heat by continuously withdrawing control rods.
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lThe apparent violat' ions discussed in the predecisional enforcement conference are subject to
further review and are subject to change prior to any resulting enforcement action
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ZAP 300-01B, " Reactivity Management Guidelines," Revision 1, Section
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G.1.1, requires the Qualified Nuclear Engineer to implement the reactivity
management policy by providing technical advice on assigned system and
reactivity related matters.
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Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
21,1997, the Qualified Nuclear Engineer failed to provide technical advice
to the primary Nuclear Station Operator concerning the excessive control
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rod manipulations.
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ZAP 300-01, " Conduct of Operations," Revi.s. ion 3,Section IX.E. requires
the individual who is to perform the activity is responsible to adequately
review the procedure.
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Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
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21,1997, the primary Nuclear Station Operator, Unit Supervisor and Shift
Engineer failed to adequately review General Operating Procedure (GOP)
4, " Plant Shutdown and Cooldown," prior to performing the Unit 1
shutdown.
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ZAP 300-02, "Use of Procedures in Operating Department," Revision 10,
Section VI, requires that 1E an activity or evolution should not or cannot
continue per the governing procedure as written, THEN; immediately
notify the responsible supervisor.
Contrary to the above, an activity affecting quality was not accompiished
in accordance with the applicable procedure. Specifically, on February
21,1997, upon determining that the reactivity changes should not
continue per GOP-4, step 5.21 f ine primary Nuclear Station Operatur
continued to perform reactivity manipulations and did not notify the Unit
Supervisor.
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GOP-4, " Plant Shutdown and Cooldown," Revision 13, step 5.21.f, states,
" Hold "#363, ROD MOTION CONTROL" switch IN to minimize dumping
steam and establish power at or less than the Point of Adding Heat (2.5 x
10E-2% intermediate range (IR))."
Contrary to the above, an activity affecting quality was not accomplished
in accordance with the applicable procedure. Specifically, on February
21,1997, the primary Nuclear Station Operator failed to follow GOP-04,
step 5.21.f, in that, he failed to manipulate the control rods to establish
reactor power at the point of adding heat.
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The apparent notat ions discussed in t he ;;reaecisional einormwn1 , on w -w e oro
forther revies and are subject 1o chance or mr t e anv + wit o'
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lhe apparent violations discussed in the predecisional enforcement conference are subject to
further review arid are subject to chanqe prior to any resulting enforcement action
2.
10 CFR Part 50, Appendix B, Criterion XVI," Corrective Actions," requires that
rneasures be established to assure that conditions adverse to quality are
promptly corrected, and in the case of significant conditions adverse to quality,
that measures be established to assure that the cause of the condition is
determined and corrective actions taken to preclude recurrence,
Contrary to the above, on February 23,1997, conditions adverse to
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quality -- such as command and control, reactivity management, and
communication deficiencies - were not promptly corrected prior to
retuming licensed operators that were involved in the February 21,1997,
reactivity management event to licensed duties.
b.
Contrary to the above, from February 28,1996, to February 21,1997,
following the identification of an adverse trend in reactivity management
activities -- a significant condition adverse to quality -- measures were not
established to determined the cause of the adverse trend and corrective
actions were not taken to preclude recurrence as demonstrated by the
February 21,1997, reactivity management event.
Contrary to the above, from April 8,1996, to February 21,1997, following
c.
receipt of a Notice of Violation (50-304/96005-03) that identified an
inadvertent mode change -- a significant condition adverse to quality that
was caused by poor communications, weak command and control, and
poor reactivity management - corrective actions taken to preclude
recurrence were not adequate to preclude recurrence as demonstrated by
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the February 21,1997, reactivity management event.
d.
Contrary to the above, from September 16,1996, to February 21,1997,
corrective actions taken to preclude recurrence of conditions adverse to
quality -- such as command and control, communication, and reactivity
management problems --identified during the Unit 1 startup were not
adequate to preclude recurrence as demonstrated by the February 21,
1997, reactivity management event.
hee car ent violations discussed in the predecisional enf orcement conf erence are subject to
furth0r nmew and are subject to change prior to any resulting enforcemont action
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The apparent violations discussed in the predecisional enforcement conference aro subject to
further review and are subject to change prior to any resulting enforcement action
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3.
Technical Specification (TS) 3.1. " Reactor Protection Instrumentation and Logic."
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requires, that with the minimum number of operable channels below the limits
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specified by Table 3.1-1, " Reactor Protection System - Limiting Operation
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. Conditions and Setpoints," plant operation shall be as specified in Column 5 of
' Table 3.1-1 which required that if minimum conditions are not met within 24
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hours, the unit shall be in Cold Shutdown conditions within an additional 24
hours.
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Contrary to the above, on February 24,1997, the licensee failed to comply with-
the Limiting Condition for Operation of TS 3.1 when Unit 1 was not placed in cold
shutdown conditions within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> of rendering all three-reactor coolant
system loop "A" flow instrumentation channels inoperable.
4.
10 CFR Part 50, Appendix B, Criterion XVI, " Corrective Actions," requires that
measures be established to assure that conditions adverse to quality are
.promptly identified and corrected, and in the case of significant conditions
adverse to quality, that measures be established to assure that the cause of the
condition is determined and corrective actions taken to preclude recurrence
Contrary to the above, from September 2,1996, through March 8,1997, the
licensee had not established measures to assure that the cause of a significant
condition adverse to quality - gas accumulation within the Unit 1 reactor vessel
head, on September 2,1996 -- were determined and corrective actions taken to
preclude recurrence. As a result, the event recurred and a significant gas
accumulation was identified within the Unit 1 and Unit 2 reactor vessel head en
March 8,1997. Additionally, the licensee had not adequately evaluated and
implemented timely and effective corrective action for generic industry
information pertaining to the accumulation of gas in the reactor coolant system.
inaccurate water levelindication while shutdown, loss of reactor coolant
inventory while shutdown, and gas transfer from the volume control tank to
various safety related systems, which could have precluded the September 1996
and March 1997 events from occurring.
The apparent violations discussed in the predecisional enforcement conference are suh.jea o
further review and are subject to change prior to ary resulting enforcment action
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The apparent violations discussed in the predecisional enforcement conference are subject to
further review and are subject to change prior to any resulting enforcement action
5.
10 CFR Part 50, Appendix B, Criterion V, " Instructions, Procedures, and
Drawings," requires that activities affecting quality be prescribed by documented
instructions, procedures, or drawings, of a type appropriate to the circumstances
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and be accomplished in accordance with these instructions, procedures, or
drawings.
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Contrmy to the above, as of March 8,1997, procedures for activities
a.
affecting quality such as extended operation in cold shutdown were not
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appropriate to the circumstances. Specifically, no operating procedures
were prescribed which provided guidance on maintaining indication of
reactor vessel water level while the plant was in cold shutdown.
Consequently, this prevented the timely identification and resolution of
gas accumulation within the reactor vessel.
b.
Contrary to the above, as of April 2,1997, operating procedures utilized
for activities affecting quality during cold shutdown conditions were not
appropriate to the circumstances in that they did not include measures to
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diagnose or prevent the undetected accumulation of gas in the reactor
coolant system. Specilically:
(1)
PT-0, Appendix E-3, Operating Surveillance Checksheet,"
(Nuclear Station Operator's shiftly surveillance while in Mode 5) did
not include measures to identify the accumulation of gas, such as
monitoring RVLIS. Consequently, when RVLIS was trending
downward on Unit 1 from March 4 through 8,1997, operators failed
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to identify that a void was being created in the reactor head.
(2)
Abnormal Operating Procedure 6.3, " Loss of Shutdown Cooling,"
relied on pressurizer fievelinstrumentation for determining reactor
vessel water level. Consequently, had the accumulation of gas
continued to the point where shutdown cooling was affected, the
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recovery from the event could have been significantly complicated.
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op; ** < + mlat iom disc ussed in the predecisionai enf orcement conter ence ar e subject to
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f urt h,a revim and are subject to change prior to any result inq enforcement action
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The apparent violations discussed in the predecisional enforcement conference are subject to
further review and are subject to change prior to any resulting enforcement action
6.
10 CFR Part 50.72(b)(2)(iii)(B) requires that the licensee shall notify the NRC as
soon as practical, and in all cases within four hours, of any event or condition
that alone could have prevented the fulfillment of the safety function of structures
or systems that are needed to remove residual heat.
Contrary to the above, on March 8,1997, the licensee identified that gas was
accumulating in the reactor vessel head on both Unit 1 and Unit 2. This
cbndition (undetected gas accumulation in the reactor coolant system) could
have potentially caused the loss of both trains of shutdown cooling prior to the
gas bubble reaching the size where pressurizer level would have provided direct
indication of reactor vessel water level. Additionally, the gas in the reactor
coolant system could have accumulated in the steam generators which would
have resulted in the obstruction of natural circu' tion cooling. However, the
licensee did not make a four-hour non-emergency report to the NRC.
7.
10 CFR Part 50.73(a)(2)(v)(B) requires that the licensee sha;l submit a Licensee
Event Report within 30 days after the discovery of the event, for any event or
condition that alone could have prevented the fulfillment of the safety function of
structures or systems that are needed to remove residual heat.
Contrary to the above, on March 8,1997, the licensee identified that gas was
accurnulating in the reactor vessel head on both Unit 1 and Unit 2. This
condition (undetected gas accumulation in the reactor coolant system) could
have potentially caused the loss of both trains of shutdown cooling prior to the
gas bubble reaching the size where pressurizer level would have provided direct
indication of reactor vessel water level. Additionally, the gas in the reactor
coolant system could have accumulated in the steam generators which would
have resulted in the obstruction of natural circulation cooling. However, the
licensee did not submit a Licensee Event Repor1 within 30 days from the
discovery of the event.
lurther mm. and m e subst m cnon, primhe apparent nolauons discussed in
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ATTACHMENT
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LICENSEE HANDOUT
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Zion Station
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Enforcement Conference
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July 3,1997
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Comed - Zion Station
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Agenda
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e Opening Remarks
John Mueller
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e Shutdown Chronology
Robert Starkey
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e Safety Significance
Robert Starkey
E . Hak-Soo Kim
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.hael Burns
e Control Rod Movement
Timothy O'Connor
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Event
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NOD Cross-Site Actions
John Mueller/ Harry Keiser
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e Gas Accumulation in the RCS
George Vanderheyden
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e Technical Specification
George Vanderheyden
Compliance - RCS Flow
Instruments
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Closing Remarks
John Mueller
Comed - Zion Station
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Opening Remarks
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John Mueller
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Site Vice-President - Zion Station
Comed - Zion Station
3
. _ _ _ _ _ _ _ _ _ _ _ _ _ _ - -
_
- _ - _ -
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_ _ _ _ _
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Control Rod Movement
Event Chronology
..
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Robert Starkey
Plant General Manager - Zion Station
!
Comed - Zion Station
4
.
,
%
Shutdown Event Chronology
m m - wamrr-
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- =
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2/19
1020
1C Containment Spray Pump inoperable
1
2/21
0700
Shift turnover with Unit 1 at 42% power
0800
POD meeting addressees that Unit 1 should be prepared for shutdov/n, action
'
plan for 1C CS pump; Qualified Nuclear Engineers (QNEs) told to meet with
shift management at 0930
0800
Shift Engineer (SE) and U1 Unit Supervisor (U1 US) engaged in shutdown
preparation activities
1040
CS pump 48-hour LCO time expires; Tech Specs require Unit 1 to be in hot
shutdown within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> (by 1440)
1100
Site Vice President (SVP) holds discussions re shutdown with Unit 1 operating
,
crew management, U1 Shift Operations Supervisor (U1 SOS), U1 Operations
Manager (U1 OM), U1 Plant Manager (U1 PM)-- emphasis on safe Unit
shutdown
1110
Shutdown briefing held with Unit 1 operating crew
,
Comed - Zion Station
5
1
_
_
.
___
.
..
..
$
Shutdown Event Chronology
~__
__ m_
2/21 (cont...)
1209
Power reduction began at ramp rate of 1/4% per minute
'
1240
Independent Safety Engineering Group engineer discusses LCO expiration
time with SE
1255
SE notified the US that LCO had expired at 1020 rather than 1040 and that
shutdown clock would expire at 1420 rather than 1440
1405
18 AFW pump started
1405
SE decides that reactor should be kept criticalin Mode 1
1405+
U1 US read steps to Primary NSO (PNSO); PNSO questions whether he should
hold the rod motion switch in; U1 US reads step again; PNSO did not further
question direction
1407
PNSO began inserting control rods continuously; numerous secondary alarms
1409
During continuous rod insertion, RP1, control bank C Demand Deviation,
Control Rod Bank Limit Low and Control Bank Limit Low-Low aiarms received.
Primary QNE (PQNE) saw Bank C inserting and told PNSO that he was
uncomfortable with reactor condition
,
Comed - Zion Station
6
.
- .
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_
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-.
-
. - - .
Shutdown Event Chronology
. mm
- ;22 r r- c-
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-
,
!
2/21 (cont...)
1411
PNSO stops control rod insertion with Control Bank C at step 104
1411
Determined that control rod insertion alone resulted in reactor being in Mode 3
1412
PNSO began control rod withdrawal in attempt to return to POAH (from
substantial subcritical condition; PQNE expresses concerns to PNSO who
shares view; rod pulls continue; determined that CS pump would not be
returned to operability prior to expiration of shutdown timeclock
1414
PNSO stopped control rod withdrawal; US instructed PNSO to trip reactor
1415
Reactor tripped
1500
Two QNEs discussed concern with SE re continuous control rod insertion and
withdrawal
1551
PIF prepared, U1 SOS notified
1730
Meeting between ONE, U1 OM, U1 SOS
,
1800
U1 PM contacted by U1 OM re " procedure problem"
'
'
2230
U1 OM notifies U1 PM, updates event status
L
,
Comed - Zion Station
7
_
.
h
i
Shutdown Event Chronology
,n- m rnmarm=emammmmen
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2/22
0700
U1 PM notifies Plant General Manager (PGM) of event, then notified SVP
0900
Recreation of event on simulator
~0900
NRC notification re shutdown problems
~1000
SVP arrives at simulator; directs both units to be placed in cold shutdown
1230
SVP notifies Executive VP for Nuclear Operations of event; U1'PM contacts
NRC Resident inspector
1700
U1 PM, U1 OM, and U1 SOS discuss returning licensed individuals involved in
i
event
!
to shift; U1 OM and U1 SOS return crew to shift
2/23
0700
SE, US, PNSO resume shift duties
0850
U1 US initiates PIP re GOP-4, step 5.21.f
1000
Meeting between SVP, PGM, U1 PM, U1 OM -- SVP directs U1 OM to remove
crew from licensed duties
1245
SE, US and PNSO formally suspended from licensed duties
Comed - Zion Station
8
>
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-
-
-
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___________
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Control Rod Movement
Event Safety Significance
-
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.
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Robert Starkey
'
Plant General Manager - Zion Station
!
.
Dr. Hak-Soo Kim
o
PWR Safety Analysis Supervisor - Nuclear Fuel Services
l
l
Michael Burns -
,
Acting System Engineering Manager - Zion Station
!
Comed - Zion Station
9
!
!
l
-
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.
-
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9
Control Rod Movement Event
'
Safety Significance
'
.
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Actual Safety Consequences
Zion Unit 1 Cycle 15- 2/21/97 Shutdown
1.00E+01
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N
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Comed - Zion Station
10
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-
-
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-
- - - -
.
-
-
-
-
.
-
-
_ _ _ _ _ - _ _
_
'
Control Rod Movement Event
~
Safety Significance
>
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--;__ _ ,
.
_
I
'
CONCLUSIONS
Actual safety consequences - None
Potential safety consequences - Minimal
Challenges to RPS
Inoperable Equipment Effect
- Containment isolation Valves
- Hydrogen Recombiner
f
- Diesel-driven Containment Spray Pump
- Main Feedwater Regulating Valve Bypass
- Penetration pressurization air compressor
- Component cooling water pump
l
.
i
.
.
Comed - Zion Station
11
i
_
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. . . .
.
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.
. - - -
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. ----
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Control Rod Movement Event
Safety Significance
amm. m-
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e Factors for regulatory significance
Management Oversight
Fundamental Knowledge / Training
Planning and Briefing
l
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Organizational Behaviors
!
Communications
Corrective Action Program
!
i
SQV/ISEG Oversight
l
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!
!
-
,
.
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Comed - Zion Station
12
l
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_ _ _ _ _
_ _ _ - _ - _ _ _ _
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-
.
.
4
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Post-Event Activities
Immediate Actions
'
,w== ;,_
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_ . _ = -
___
i
e
Directed that both units be placed in cold shutdown
i
e
Directed that Operators be removed from shift
'
e
Requested initiation of Level i PIF investigation by corporate
team
,
i
.
e
Continuous control room management oversight to cold shut-
down
!
!
I
e
Limited plant evolutions
l
Evolution coverage once in cold shut-down
!
l
!
Comed - Zion Station
13
[
!
i
.-
-
-._- ------
-
_ _ - -
- - -
_
__
Control Rod Movement Event
Corrective Actions
.
Timothy O'Connor
Restart Manager - Zion Station
,
,
Comed - Zion Station
14
-
-
-
-
-
-
- - - - - - -
. - _ - _ _ _ _
_ _ - - .
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Post-Event Activities
Corrective Actions
.
m-=_-
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_ _ . _ . . . _ . .
-
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.
Development of Comprehensive Corrective Actions
!
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e Leveli PlF
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e AIT findings
l
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1997 Business Plan analysis
independent Safety Assessment
,
Past NRC and INPO inspections
i
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!
I
l
i
i
,
i
Comed - Zion Station
15
j
.
- - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - -
- -
. _ _ _ - _ _ _ _ _ _ - - _ - _ .
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Post-Event Activities
.
Corrective Actions
1
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Obiectives of Recovery Plan
.
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e Operations performance
!
i
e Plant material condition
i
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e Demonstration of plant readiness
L
e Support to Operations
f
Effective corrective action program
j
Effective oversight
i
t
.
I
Comed - Zion Station
16
i
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-
-
-
-
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-
_ _ . . _ _ _ _ _ . - _ _ _ _ _ _ - _
_ _ .. __
.
.
Post-Event Activities
.
Corrective Actions
!
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_
Operations Performance
l
!
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Operators
!
,
o Operations selection process / crew reconstitution
l
0
,
e Operations standards
Evolution briefing
i
Communication
Board awareness
.
Decorum and formality
o Crew remediaton (Phoenix)
Comed - Zion Station
17
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- -
-
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- - . - - _ - - - - _ - - - -
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Post-Event Activities
-
.
Corrective Actions
-
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Operations Performance (continuedD
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Management Support to Operations
-
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Defined accountabilities for all Operations positions
l
.
Clear concise chain of command
Communications flow
'
Responsibilities /accountabilities flow
q
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Traming
'
Permanent program changes
,
!
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Support for Operation's laaaership role
Procedure change process
,
System Engineering and Operations shift interface
improved Technical Specifications implementation
i
Professional work spaces
!
Operations Work Control Center
l
'
Comed - Zion Station
18
.
i
- - - - -
. - - -
- - - -
-
. - - -
-
- - -
-
_ - - - _ - - - _.-
-.- - -
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Post-Event Activities
Corrective Actions
i
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Plant Material Condition
.
e System affirmations
l
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.
Work arounds
Control room corrective work
i
Open operabilities
j
Annunciator alarms
l
Temporary alterations
!
Backlog of open temporary procedures
,
o Modifications on long standing issues
e All preventive maintenance tasks current
e Plant system performance indicator process
!
-
t
!
!
Comed - Zion Station
19
l
!
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-
-
-
- -
- -
,
___ _ ___ _
._____
_
!
Post-Event Activities
i
Corrective Actions
=
,. _ ,_:_.
~ ~ ~ ~ ~ ~
.-
j
Management Demonstration of Plant Readiness
j
e Plant operational testmg
l
e Verification of Operator performance by observation
Adherence to standards
,
Preplanning of evolutions
,
Control of evolutions by shift management
i
'
Crew communications
Control room decorum and formality
f
e Verification of site team's support of Operations
Identification of issues and communications to management
Correct issues that affect the operators
'
n
Getting work done to support Operations
l
Minimal distractions to the control room
f
e
Performance evaluation review
Comed - Zion Station
20
l
!
. -
- - - -
- -
- . - _ _ _ - - _ _ _ _ - _ _ _ _ _ _
..
-
..
Post-Event Activities
!
Corrective Actions
!
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Management Support to Operations for Continuous
!
Improvement
'
<
-
l
Timely and Effective Corrective Actions
e Corrective action program improvements
.
'
Implement Corporate Corrective Action Program (NSWPs)
increase management involvement - Condition Review Group
j
Improve corrective action effectiveness - Corrective Action Review Board
!
Expand root cause analysis training
j
e Operation experience review
i
Review previous 5 years of OPEX information
f
Screen items for evaluation prior to restart
{
e Department self assessments
i
Focus support for Operations
Establish critical self assessment capability
Comed - Zion Station
21
I
.
!
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _
,
?
-
Post-Event Activities
1
Corrective Actions
<
--__._.,ex-
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maan__
Management Support to Operations for Continuous
l
'
Improvement i continued.h
.
.
I
!
!
,
,
Verification of Timely and Effective Corrective Actions
!
>
!
e SQV independent assessments
Focused operations assessments
!
Assess effectiveness of the Recovery Plan objectives
!
o
e Safety Review Board oversight
i
i
i
e Corporate review and assessment
i
i
!
Comed - Zion Station
22
.
-
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-
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Nuclear Operating Division
Cross-Site Actions
!
!
I
s
.
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I
John Mueller/ Harry Keiser
l
!
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t
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!
!
I
I
Comed - Zion Station
24
i
!
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_-
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Nuclear Operations Division
Cross-Site Actions
.
i
_____
m___
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- -srww.m _
~
e Operations Performance
f
!
i
e Training
!
!
e
Roles and Responsibilities
l
!
e
Policies
!
i
!
!
!
i
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!
!
l
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Comed - Zion Station
25
i
!
,
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. . - . -
. - . . - . - .
. . . - . - - - . .
!
.
,
,
-===
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-
_ _ _
..-,,, _ _
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,
'
Gas Accumulation in the ~
!
,
!
George Vanderheyden
Operations Manager - Zio'n Station
'
!
l
,
!
,
,
!
e
.
.
Comed - Zion Station
26
!
____________.__--_______________________________--__________j
-_
-
Gas Accumulation in the RCS
,
Chronology
m'.Y .L :.'.' ETT' 1.'..'4 M."Je" J"'9 7.-Di ', ;Trd (I / 7"'
'?~
'
' ~ M' " S
'
,
9/1/96
Gradual decrease in Unit 1 reactor vessel water level noted on RVLIS
9/2/96
U1 reactor vessel head vented; determined that 1028 gals. required to fill vessel;
root cause investigation initiated
10/30/96 Root cause investigation, recommended corrective actions approved by
j
!
Engineering, forwarded to Operations for approval
11/4/96
SQV notes unresolved CAR
12/14/96 Ops Mgr. delays addressing root cause investigation until after U2 refueling outage
j
completion based on lack of immediate concern
1/8/97
SQV update CAR, recognizing that corrective actions are overdue
2/12/97
GOP-04 entered to cool down U2 RCS to allow for thermocouple repair
2/15/97
GOP-04 exited; Mi-01 entered to partially drain the RCV for T/C repair
2/18/97
RVLIS taken OOS for 18 mo. surveillance / calibration
2/20/97
U2 RCV fill and vent completed
2/21/97
U2 RVLIS calibration completed; not returned to service (not required until after
RCS solid and pressurized): work to RTS U2 halted following U1 event
,
-
l
Comed - Zion Station
27
'
.
.
.
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.
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-
-
_--
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.
Gas Accumulation in the RCS
Chronology
_ = n:
=1 - s e =cra m m ,
ymww~
-_
__,
_
3/6/97
Control Room Operator observes increasing U2 VCT and increasing U2 PZR level
t
3/7/97
Void confirmed; corrective actions taken -VCT pressure adjusted
3/8/97
U2 vessel vented, RVLIS placed in service (approx. 6,900 gal to fill void; U1 in
similar condition -- reactor head vented - 1090 gals required to fill void) PlF written by
Operations Manager
,
3/18/97
ISEG submits revision to upgrade unresolved CAR (for 9/96 event) to Severity Level 1
-
3/25/97
System Engineering recognizes ongoing accumulation of U2 vessel head
'
'
gasses
3/29/97
U2 vented gases sampled -- air indicated, results questioned
4/3/97
PT-0, App. E-3, " Operating Surveillance Checksheet" revised to implement Operating
Special Procedure 97-014, " Maintaining RCS Conditions in Mode 5"
4/4/97
Team established to review voiding circumstances and ongoing gas accumulation
4/6/97
U2 gases sampled; gases consistent with VCT gas composition
!
,
,
,
'
Comed - Zion Station
28
,
.
.
.
.
. -
.
.
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-
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-
.
_ _ _ _ _ _ _ _ .
_ _ _ _
!
Gas Accumulation in the RCS
,
i
Immediate Corrective Actions
eerw__ _ _ .
_ ___e==--
i
l
Operators informed senior management
j
e
i
!
i
A procedure was developed and implemented to vent gas
j
e
.
!
e
Put RVLIS in service
l
.
.
i
Lowered VCT pressure
.
e
i
!
-
Standing order to vent daily
e
!
i
!
!
!
Comed - Zion Station
29
!
l
- - -
--
-
-
-
--
- - -
--
-
.
_
_
_.
_ _ _
.
- _ _ _ _ . _
_
.
-
h
r
Gas Accumulation in the RCS
.
Gas Accumulation Analysis
---=L_ ._
_._;/=====~=~= -
i
e Primary mechanism for accumulation understood
.
Higher gas solubility in VCT than in RCS
Analytical confirmation
Validated by effectiveness of corrective measures taken to
i
eliminate
!
- Fully effective on Unit 1
- Ongoing accumulation (~10% of original rate) on Unit 2
l
Same mechanism as September 1996 event
j
e Ongoing accumulation controlled on Unit 2
'
Procedures for diagnosis
,
Routine venting
Accumulation ceased following pressurizer level increase
No accumulation observed since 6/3/97
i
Comed - Zion Station
30
.
'
. .
-
-
- _ _
_ - -
_ _
_
_ .
.
--
.
.
Gas Accumulation in the RCS
Gas Accumulation Ana~ Lysis
m
-awm3_
y
m a c rz. m
Reactor vessel and relevant elevations
.
e
591'-0" Vessel flange
,
e
588'-4.5"
Water level in vessel
e
584'-8"
Procedural low limit for mid-loop operation
,
e
584'-6"
Surge line is uncovered
[
-
e
584'-3"
WCAP-11916 minimum conservative hot leg
level that avoids air binding @ 3000 gpm (includes
1" for instrument inaccuracies)
<
e
584'0"
Center line of the hot leg
e
578'-10"
Top of the core
Discussion
'
e
Self arresting gas accumulation @ el. 584'-6"
e
Although Zion has experienced air binding when RCS <584'-6"
Pressurizer level adds NPSH to RHR pump
,
e
Unlikely that Zion would experience a loss of shutdown cooling
e
Core would remain covered
Comed - Zion Station
31
,
.
t
_
- - _ _ . _ .
- _ _
- . .
_ _ _ _
. -
_
_ -
t
Gas Accumulation in the RCS
.
Causal Factors
!
__ _ _ _ _,namwem-
33;g wrm_
__
_
-
e Corrective action follow-up incomplete
l
!
e Evaluation and implementation of industry information
t
!
r
e
Procedure scope
l
.
i
e Lack of training on RVLIS use during shutdown
t
?
!
!
l
t
!
!
!
!
Comed - Zion Station
32
I
!
.
.
-
-
- -
-
-
- -
i
_ - - _
- _
-
- - - _ - - - -
_
E
!
Gas Accumulation in the RCS
Causal Factors anc Corrective Actions
--m_.=w
mm:m.m emmm-
,
_,
__
i
e Causal Factor
[
Corrective action follow-up incomplete
>
-
e Corrective Actions
t
Corrective Action Program enhancements
Daily focus on corrective actions
'
i
t
)
'
!
!
!
l
Comed - Zion Station
33
-
..
_ _
- _
_ _
_ _ _ _ . -
_ _ .
- .
_
.
Gas Accumulation in the RCS
Causal Factors ancL Corrective Actions
.
. . - - ,. _ ~ = =
- : = = ,= = _ ,
_ _ _
_
'
eCausal Factor
Evaluation and implementation of industry information
i
eCorrective Actions
j
Five year review of past OPEX information
New Operating OPEX staff position dedicated to providing
j
additional levels of review for-
!
r
- Applicability of OPEX, and
l
,
- Breadth of responsive actions
!
L
I
-
i
!
,
5
i
i
Comed - Zion Station
34
f
l
-
-
-
-
_
Gas Accumulation ~in the RCS
i
Causal Factors ancL Corrective Actions
---
_:- -
--
-
e Causal Factor
'
Procedure Scope
.
e Corrective Actions
OSP 97-014, " Maintaining RCS Conditions in Mode 5," developed
and implemented
.
- Reduce accumulation due to solubility
[
Depressurized VCT
e
e Adjust RCS/VCT temperature
- Monitor RVLIS
- Instructions on Venting
Survey industry for best practices
!
!
.
Comed - Zion Station
35
i
.
- -
-
- -
-
-
- - - - -
_ - - _
- - - _
_.
.__
_
!
!
Gas Accumulation in the RCS
.
Causa~ Factors anc. Corrective Actions
l
__--ng;
__
- g -
= - - -
_
, ,
_
1
eCausal Factor
!
.
Lack of training on RVLIS use during shutdown
eCorrective Actions
,
!
On-shift training provided to the operators
Training added to ILT and LOCT for RVLIS operation and gas
f
accumulation when shutdown
-
,
Comed - Zion Station
36
!
. -
-
.
.
- . - . .
Gas Accumulation in the RCS
.
Safety Significance
m.
~"-= -
- .-
Regulatory Significance
,
e
Response to generic communications
o
Corrective action implementation
e
Procedures
e Training
j
Actual Safety Consequences
-
e
None
!
Potential Safety Consequences
i
e
Minimal
~
New core
i
Unlikely to affect shutdown cooling
Reduced RCS inventory
l
Becomes self venting
!
-i
Comed - Zion Station
37
'
_ _ - - -
-_-_
_
_- -.
-.
Gas Accumulation in the RCS
-
Reporting
.
- -
u =u--
,
-
.- . = 3 ,_ _
_
_
=
-
-
.
,
'
o Comed recognizes the importance of voluntary NRC
notification for events such as this
,
'
e Our evaluation determined:
The event did not actually affect or involve component or train
i
The event alone could not affect component or train
,
i
!
.
.
t
.
,
>
l
,
Comed - Zion Station
38
!
!
'
i
- -
.
_ _
-
.
-
_ -
-
- -
_-- .
.
.
,
c.s
5 w s2gziPJ35TEC
M""
- " ; ?.
- '~717,:;f-?**PCE4 m
_ ' m - v . n .2 t_. 2
_
!
I
.
Gas Accumulation in the RCS
1
Closing Remarks
t
>
I
i
John Mueller
Site Vice-President - Zion Station
!
.
i
!
i
t
.
'
Comed - Zion Station
39
!
$
r
- - - _ - - - - - - .
.
.
-
-- . .
.
I
h
i
e
'
t
f
1
?
M M '~ m :\\vi:smgz M m2 % '- _ _ _~ _. no r, ~
3Q~7 2 y;'; ?gi;3:3=m
- > vet m_.,
i
f
Technical Specification
Compliance - RCS Flow
'
Instruments
l
!
I
(
i
George Vanderheyden
j
'
!
Operations Manager - Zion Station
t
I
i
!
[
i
e
t
r
Comed - Zion Station
40
!
!
!
-
-
RCS Flow Instruments
Chronology
m ~ - -
.,.=y s x = -
_
_ ; ;n;:m=wm
.
_
2/22
1310
Loop A Flow Transmitters authorized for OOS
1330
Informed that U1 will be going to cold shutdown
1454
Loop A Flow Transmitter OOS
1500
Conducted a brief of GOP-4 to take the unit to cold shutdown
2/23
1601
Started U1 RCS cooldown
-
2/24
1900
A review of TS Table 3.1-1 shows that the unit was
required to be in a LCO 2/22@14:54. Red
phone call, Unusual Event declared.
.
2/24
Cleared OOS (Loop A RCS Flow Transmitter)
2/25
2123
Cold shutdown
Comed - Zion Station
41
, _
-.
..
.
.. ..
.--
-
-
-
. .-
- - - _ _
___ _ - _ _ _ _ - _ _ _ _ .
e
!
RCS Flow Instruments
..
Causal Factors
'
.
?$
Y'
AWSh h i
5
5
,
-w
t
1
!
i
e Operators did not use Technical Specifications to
determine Action Requirements
.
j
.
%
.
i
!
1
!
I
.
'
i
i
.
Comed - Zion Station
42
-
.
- - -
-
- -
-
-
-
-
-
-
-
-
- -
-
__
..
.
.
l
RCS Flow Instruments
.
.
Corrective Actions
.
_--a
.-
37_,,_
- en=u== _
.
t
e Standards clearly define use of Technical Specifications
,
o Created training exercises to train on Technical
Specification use
o Evaluation of crews performed to verify standards are met
e Expectations reinforced on-shift with on-shift monitoring
i
and management observation
'
Comed - Zion Station
43
i
-
-
-
- - -
.
.
t
RCS Flow Instruments
,
Sa ety Significance
e
t
_- -_ ,_w.3
3:=g=n,__
Regulatory Significance
e Technical Specifications must be implemented as written
Actual Safety Consequences
e
None
.
Potential __Safetv Consequences
e
Minimal
Instrument basis is that below the P-7 setpoint, all reactor trips on
low flow are not required since no conceivable power distributions
-
could occur that would cause a DNB concern at this low power
~
level
Safety function already performed (trip breakers were open)
.
1
'
Comed - Zion Station
44
.
.
.
.
.
m
. - _ . . . _ - - - - . . .
. - - . .
. . . . - . .
.
-
...
-
..
-
.
_n_-.__an; __
_,;~ynza_
Closino Remarks
o
.
John Mueller
Site Vice-President - Zion Station
Comed - Zion Station
45
_
_
- _ - .
. _ _ - _ - _ _ -
_
_
-
_
' , ' '
&
do
b
4
.
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AdditionalInformat: ion
.
!
-
,
.
,
P
1
e
4
Comed - Zion Station
46
!
c
-
-
!
.
..- .
.
_ _ . _
_ _ _ _ - .
.__ _
._
- _ __
Enforcement Issues
Summary
-
..=_.. - a,# w = m u n = y
m r n w m n;,32,w g u y_ m .
-
==m"-r -
nwmes%
.._
issues
Regulatory
Causal Factor (s)
Corrective Action (s)
Number
Reference
(Areas in Recovery Plan)
97007-O l a
The failure of operations supervision
Crit V;
Planning & Ilricting
Action Plans 2, Operator Remediation
to conduct an infrequently performed
ZAP 300-01
and Training ; 3; Operation's Standards
evolution brief to maintain the reactor
and Expectations; 4, Ops Readiness
at the POAll.
Program; 5, Procedures,9. O ff-shift
Command & Control.
97007-O l b
The failure of the SE to maintain a
Crit V;
Management Oversight
Action Plans 2, Operator Remediation
broad perspective on operational
ZA P 300-01
and Training; 3, Operation's Standards
conditions affecting safety, which was
and Expectations.
reflected in the failure to recognize
significant control rod m anipulations.
97007-Olc
The failure of the US to be attentive to
Crit V:
Management Oversight
Action Plans 2, Operator Remediation
the condition of the plant at all times
ZAP 300-01
and Training; 3, Operation's Standards
which was reflected in the failure to
and Expectations.
recognize significant control rod
manipulations.
97007-O l d
Conduct of control room activities
Crit V;
Organizational llehaviors
Action Plans 2, Operator Remediation
during the Unit I shutdown in a
ZAP 300-01 A
and Training; 3, Operation's Standards
manner that compromised on-shift
and Expectations; 4, Operational
licensee personnel attentiveness and
Readiness Program.
the professional [ control room]
atmosphere. Specifically, the US and
SE were not attentive to ongo:ng
control rod manipulations and the
noise level in the control room
compromised crew communications.
Comed - Zion Station
47
-
-
_ _ __
__ _
_ _ _ _ _ .
_
_.
. _ _
_
- . _ _ _ _ . ___
Enforcement Issues
.
Summary
mang~ ww
s,1; 3:;'
m wmmm
.a,,,
v v, nam
._
eel
Jssuer
Regulatory
Cause(s)
Corrective Action (s)
Number
Reference
(Areas in Recovery Plan)
97007-Ole
When the NSO did not understand the
Crit V;
Com m unications;
Action Plans 2 Operator Remediation and
guidance from the US concerning
ZAP 300-09
Fundamental know ledge /
Training Program; 3, Operation's
driving in control rods, the NSO failed
training
Standards and Expectations; 4,
to inform the US to repeat or rephrase
Operational Readiness Program: 5,
his guidance.
Procedures.
97007-01 f
The failure of the NSO and US to use
Crit V;
Com m unications;
Action Plans 2, Operator Remediation and
three-way communications.
7. A P 300-09
Fundam ental know ledge /
Training Program; 3, Operation's
training
Standards and Expectations; 4,
Operational Readiness Program; 5
Procedures.
97007-Olg
By excessively inserting control rods
Crit V;
Fundamental knowledge /
Action Plans 2, Operator Remediation and
and then non-conservatively
ZAP 300-01
training
Training Program; 3. Operation's
withdrawing control rods, the primary
Standards and Expectations; 4,
NSO failed to perform reactivity
Operational Readiness Program; 5,
manipulations in a controlled manner.
Procedures.
97007-Olh
The failure of the primary NSO to stop
Crit V:
Fundamental knowledge /
Action Plans 2. Operator Remediation and
and question the excessive rod
ZAP 300-01B
training
Training Program; 4, Operational
manipulation.
Readiness Program; 5, Procedures.
97007-Oli
The failure of the QNE to provide
Crit V;
Com m unications;
Action Plan 4, Operational Readiness
technical advice for the excessive
ZAP 300-0111
Organizational llehaviors
Program .
inward and outward control rod
manipulations.
97007-O lj
The failure of the primary NSO, US
Crit V;
Planning and Briefing;
Action Plans 3, Operation's Standards and
and SE to adequately review GOP-4
ZAP 300-01 (!
Organizational Behaviors
Expectations; 4, Operational Readiness
prior to performing the Unit i
IX.E)
Program;i5, Procedures.
shutdown.
Comed - Zion Station
48
. -
-
-
- -
Enforcement Issues
Summary
_amawa.amz.n" '=m:^ ': M
?~Y:~7* W rwL M
_mm
, , .
-,,,.m_,_
eel
Issue
Regulatory
Cause(s)
Corrective Action (s)
Number
Reference
(Areas in Recovery Plan)
97007-Olk
The failure of the NSO to immediately
Crit V;
Communications;
Action Plans 2, Operator Remediation
notify the responsible supervisor aRer
GOP-4 (Step
Fundamental knowledge /
and Training Program: 3, Operation's
determining that the continuous
5.21.f); ZAP
training
Standards and Expectations; 4,
control rod insenion and withdrawal
300-02
Operational Readiness Program; 5,
should not continue.
Procedures.
97007-011
The failure of the primary NSO to
Crit V;
Fundamental knowledge /
Action Plans 2. Operator Remediation
manipulate control rods to establish
GOP-4 (Step
training
and Training Program; 3, Operation's
power level at the POAll.
5.21.0
Standards and Expectations; 4,
Operational Readiness Program; 5,
Procedures.
97007-02a
The licensee's failure to correct
Crit. X VI
Corrective Actions
Action Plans 8, Corrective Actions 9,
command and control, reactivity
Off-shift management Command &
management, and communication
Control
deficiencies, exhibited by the SE, US,
and primary NSO,and which n;re
contributing causes of the February 21
improper control rod manipulation
event, before returning the operators to
licensed duties.
97007-02b
The failure of the licensee to take
Crit. XVI
Corrective Actions
Action Plans 8 Corrective Actions; 9,
adequate corrective actions to address
Off-shift management Command &
the adverse trend in reactivity
Control
management activities.
.
Comed - Zion Station
49
-
.
-
- _ _ - - _ _ _ _ _ .
. - - - - - - - . _ _ - - _ . _ _ _ - -
_
_ __ __ -.
_ _ _ _
_ - _ . _ - - _ - .
. - _ _ _ _ .-_ _
__
- - - - _ - _ _ _ _ - _ _ _ - _ _ _ _ _ _ - _ - _ _ _ _ _ - _ _ - _ - - _ - -
Enforcement Issues
Summary
-
myrt;r m y ~ . y, :wmm
.
- -- =
.~. =x u : ; ?
' __- # --
m : w m
.a s
___
-,
n ,
, , _ _ .
eel
Issue
Regulatory
Cause(s)
Corrective Action (s)
Number
Reference
- (Areas in Recovery Plan)
97007-02c
The failure of the licensee to take
C rit. X V I
Corrective Actions
Action Plans 8, Corrective Actions; 9,
adequate corrective action to prevent
Off-shif1 management Com mand &
recurrence of command and control,
Control
communications, and reactivity
management problems, identified as a
result of an inadvertent mode change
in January 1996.
97007-02d
The failure of the licensee to take
Crit. X VI
Correctisc Actions
Action Plans 8. Corrective Actions; 9,
adequate corrective action to prevent
Off-shift management Com mand &
recurrence of command and control,
Control .
comm unications, and reactivity
management problems, identified as a
resuit ofinappropriate control rod
manipulations during a Unit I startup.
97007-03
The licensee's failure to comply win
I S 3.1
Procedures; Verification
Action Plan 9, O ff-shift management
.
TS 3.1 and place Unit I in cold
Practices; Review Process
Command & Control
!
shutdown within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> following
all three RCS loop "A" flow
instrumentation channels being
rendered inoperable,is considered an
apparent violation.
97002-01
1 he failure to implement timely and
Crit. X VI
Correctn e Actmns
A ction Plans M, Corrective Actions; 9,
effective corrective actions for a
O ff-shift management Com mand &
>
previous instance of undetected gas
Control
accumulation in the reactor coolant
system in Septem ber 1996.
Comed - Zion Station
50
_ _ -_-_-_____ __.
. - _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
._
_ _ - _ _ _ _
__ _ _ _ _ _ _ _ - _
__ _ __ ____-
. _ _ _ _ _
. _ _ _ _ _ - _ - _ - _ _ _ _ - - _ _ _ _ _ - _ _ _ _ _ - _ _ _ -
.
Enforcement Issues
Summary
mn,wn c , anacov
~
'~ m . .wggaw_ .
eel
Issue
Regulatory
Cause(s)
Corrective Action (s)
Number
Reference
(Arras in Recovery Plan)
97002-02
De failure to have procedures for
Crit. V
Fundamental knowledge /
Action Plans 8, Corrective Actions, I I
extended operation while in cold
training; Management
Operating Experience
shutdown conditions and for operating
Oversight; Corrective
procedures toinclude measures to
Actions
diagnose or prevent the undetected
accumulation ofgas in the reactor
coolant system.
97002-03
De failure to make a four-hour non-
10 CFR Part
N/A
N/A
emergency report and submit a written
50.72(b)(2)(iii)(B)
Licensee Event Report within 30 days,
-
for a condition that alone could have
prevented the fulfillment of the safety
function to remove residual feat.
97002-04
The failure to make a four-hour non-
10 CFR Part
N/A
N/A
emergency report and submit a written
50.73(a)(2)(v)(B)
Licensee Event Report within 30 days,
fora condition that alone could have
prevented the fulfillment of the safety
function to remove residual heat.
Comed - Zion Station
51