ML20149H996

Predecisional Enforcement Conference Rept on 970703.Areas Discussed:Violations Noted in Insp Repts 50-295/97-02, 50-304/97-02,50-295/97-07 & 50-304/97-07 on 970206-0402 & 0312-0428 & Corrective Actions

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: ML20149H986 ML20149H996
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: DPR 39; DPR-48

l Licensee: Commonwealth Edison Company

Facility: . Zion Generating Station

I - Dates: July 3,1997 ~

. 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,

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along with the corrective actions taken or planned by the licensee. The apparent violations

, L concerned performance deficiencies exhibited during the reactivity control event on

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 *

PDR ADOCK 05000295

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Beport Details ,

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l. 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-  !

K. Graesser, Site Vice President, Byron I

G. Stanley, Site Vice President, Braidwood 1

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 R

R. Starkey, Plant General Manager, Zion i

R. O'Connor, Recovery Plan Manager, Zica

R. Zyduck, Site Quality Verification Director, Zion 1

T. Luke, Engineering , Manager, Zion

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. - G. Vanderheyden, Operations Manager, Zion

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l L. Kelley,: Acting Training Manager, Zion . j

K. Dickerson, Executive Assistant, Zion

R. Godley, Regulatory Assurance Manager, Zion

D. Farr, Operations Manager, LaSalle '

l R. Wegner, Operations Manager, Byron

D. Cooper, Corrective Action Manager, Comed

T. Gierich, Operations Manager, Byron

D. Cook, Operations Manager, Quad Cities i

T. Palanyk, Acting Assistant Shift Operations Supervisor, Dresden .

D. Ferg, Lead Offsite Reviewer, Comed

M. Burns, Acting System Engineering Supervisor, . Zion

i M.-Korchynsky, Shif t Manager, Dresden

l B. Kugelbery, Communications Director, Comed

l H Kim, PWR Safety Analysis Supervisor, Comed

J. Lewand, Corporate Licensing, Comed l

D. Smith, Nuclear Communications, Comed

p 1. Johnson, Licensing Director, Comed

l F. Spangenberg, Regulatory Assurance Manager, Dresden

H L. Holden, Nuclear Licensing Administrator, Comed ,

L C. Peterson, Regulatory Affairs, Quad Cities 'l

l 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 i

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) i

B. Berson, Regional Counsel, Rill '

M. Ring, Chief, Engineering Branch, Rlli

M. Leach, Chief, Operator Licensing Branch, Rill

M. Dapas, Chief, DRP Branch 2, Ritt I

M. Parker, Acting Chief, DRP Branch 2, Rlli

D. Hills, Project Engineer, Rill l

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 I

C. Nicodemos, Reporter, Chicago Sun-Times l

P. Kendall, Chicago Tribune

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J. Yesinowski Resident Engineer, Illinois Department of Nuclear Safety l

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

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identified. Inspection findings were documented in inspection Report

Nos. 50-295/97002; 50 304/97002 and 50-295/97007; 50-304/97007,

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transmitted to the licensee by letters dated June 4 and May 21,1997, respectively.

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

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NRC HANDOUT l

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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.

a. Zion Administrative Procedure (ZAP) ZAP 300-01, " Conduct of ,

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,

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significant control rod manipulations made by the primary Nuclear Station

Operator went unnoticed.

b- 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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i. c. ZAP 300-01 A, " Control Room Access and Conduct," Revision 4 Section

i Vill.A, requires that Control Room business SHALL be conducted at a

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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

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the control room and other numerous distractions caused a loud and - l

disruptive environment. As a result, licensed personnel attentiveness and

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.  !

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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 i

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 l

had the potential for adversely affecting reactivity control- without

conducting a pre-evolutionar / briefing for this infrequently performed {

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. evolution.

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e. ZAP 300-09, " Station Operational Communications," Revision 3, Section i

Vll A.3, requires that if the receiver does not understand the

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 i

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

l supervisor to repeat or rephrase his message.

tre accarent violations discussed i'1 the riredecisionn) enforcemem mnf erence are sonmct

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c aer ruiew and are sutuect to chnrme prior h am teu tno em imwt ar t im

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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 '

L f. ZAP 300-09, " Station Operational Communications," Revision 3, Section

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~' Vll.A.3, requires that all operational communications .Sil A LL utilize three-

way communications. The procedure further defines three-way ,

communication as "The technique of the sender issuing a communication  ;

' 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 ,

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Supervisor (the receiver) failed to use three-way communications, in that,

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.

g. 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 1

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.

h. 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. 1

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 ,

reactivity controls when he did not stop and question unexpected changes -

in reactivity and power level as he continuously inserted control rods. As

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a result the primary Nuclear Station Operator made the reactor

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 '

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' "n 9 o  : a*m

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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,

a. Contrary to the above, on February 23,1997, conditions adverse to

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.

c.

Contrary to the above, from April 8,1996, to February 21,1997, following

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

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recurrence were not adequate to preclude recurrence as demonstrated by j

the February 21,1997, reactivity management event.

d. Contrary to the above, from September 16,1996, to February 21,1997, l

corrective actions taken to preclude recurrence of conditions adverse to

quality -- such as command and control, communication, and reactivity l

management problems --identified during the Unit 1 startup were not l

adequate to preclude recurrence as demonstrated by the February 21,

1997, reactivity management event. l

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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."

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

. 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 1

hours, the unit shall be in Cold Shutdown conditions within an additional 24

hours. -

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 I

drawings. ,

a. Contrmy to the above, as of March 8,1997, procedures for activities l

affecting quality such as extended operation in cold shutdown were not '

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 l

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

l 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

j recovery from the event could have been significantly complicated.

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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.

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ATTACHMENT .

LICENSEE HANDOUT

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Zion Station i

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Enforcement Conference .

July 3,1997 .

Comed - Zion Station 1

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Agenda

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e Opening Remarks John Mueller

e Shutdown Chronology Robert Starkey

e Safety Significance Robert Starkey

E . Hak-Soo Kim

i .hael Burns  ;

e Control Rod Movement Timothy O'Connor .

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Event

NOD Cross-Site Actions

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e John Mueller/ Harry Keiser

e Gas Accumulation in the RCS George Vanderheyden -

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e Technical Specification George Vanderheyden

Compliance - RCS Flow

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Instruments

e Closing Remarks John Mueller

Comed - Zion Station 2

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Opening Remarks

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John Mueller -

Site Vice-President - Zion Station

Comed - Zion Station 3

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Control Rod Movement

Event Chronology ..

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Robert Starkey

Plant General Manager - Zion Station

Comed - Zion Station 4

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Shutdown Event Chronology

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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 .

_ _ _ - . _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ . _ . . _ _ _ _ _ . _ _ . _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

_ . . -. - . - - .

Shutdown Event Chronology

. mm - ;22 r r- c- r-,- rm - -

,

!

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

mamme=z:smsmemu m7 7 ,_ , ,_ _

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 >

. _ __ _ ______ _ ________ _ _ __ _ - ______________ _ -__-__ _ - ____ _ -__ _ _ _ __ _________ _ _-______ ___ _ _ _ - _ _

___________ __-__

t

__.__eh a 3 L T' ' ._g QQ?Q'y"QQ-Q"jf

~

_

'I ',

Control Rod Movement

Event Safety Significance -

.

i

Robert Starkey

'

Plant General Manager - Zion Station

Dr. Hak-Soo Kim

o

PWR Safety Analysis Supervisor - Nuclear Fuel Services

Michael Burns - ,

Acting System Engineering Manager - Zion Station

Comed - Zion Station 9

!

l

_ _ _ - _ _ _ _ _ _ . . _ - _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ - _ _ _ _ _

_ .._ - _. . . -

9

Control Rod Movement Event '

Safety Significance

'

.

- - -wamy _

. w: w=m:.:w .nauww--  ;

Actual Safety Consequences '

Zion Unit 1 Cycle 15- 2/21/97 Shutdown

1.00E+01 i

500

/

7-- pI ug "x

~

'

!  !  !

l

O E

1.00E+00 ' j j j j 8,

~

! , :  : ' -

-500 .

. m

l

>

3  ;

7

-

1.00E-01 .,

.

. '.

i

l 4 _1000E-  !

, .

ai l -8

.  : E  :

$ 1.00E-02 i j o j -1500 g  ;

o.,7"

.

1 '

o N0036' Power - % --do s -2000 E

^ "

1.00E-03 _

o N0035 Power - %  ; O

Core RX - pcm j -2500 g i

.

,  ; z  !

' '

1.00E-04 ' '

.

-3000

"

8 E 8 8 9 "

D 3 $ $

4 - ,4

-

4-

-

4

- ,4

-

4

- ,4

-

4

- ,4

-

4

-

4

-

N N N N N N N N

'

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Date '

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i

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L

Comed - Zion Station 10 .

___-_____---- __- _________-___-______ _ _ - _ - - - - _ . _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ - _ _ __ -__ _ __________ - _ _.____ - __-_______

_ _ _ _ _ - _ _ _

Control Rod Movement Event ~

_n

Safety Significance

--;__ _ , _

==m em_

'

CONCLUSIONS

Actual safety consequences - None

Potential safety consequences - Minimal

Challenges to RPS

Inoperable Equipment Effect

- Containment isolation Valves

- Hydrogen Recombiner

- Diesel-driven Containment Spray Pump

- Main Feedwater Regulating Valve Bypass

- Penetration pressurization air compressor

- Component cooling water pump

.

.

Comed - Zion Station 11

i

_

m a_m__._._._.__.__._. _______.__--_ _ . _ . - - - _ _ _ _ - _ _ _ _ _ _ A -a_m ._----__

___ ...__-_ _ _ __ _ _ _ __- _ _ .

Control Rod Movement Event

Safety Significance

-__mm,=

.

. ,m xw e . ~ ~ :n,

. -w ---_ _

amm. m-

e Factors for regulatory significance  ;

Management Oversight

Fundamental Knowledge / Training

Planning and Briefing

t

Organizational Behaviors  !

Communications

Corrective Action Program i

SQV/ISEG Oversight

!

i

i

!

-

,

.

I

Comed - Zion Station 12 l

"

. - _ _ _ _ _ _ _ _ - _ - _ _ _ _ _ - . -

. .

4

h

Post-Event Activities

Immediate Actions '

_ . _ = - ,w== ;,_ ___

n= = = ,=_

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  !

!

e Limited plant evolutions

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

__ _ - _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

- - - - - - - . - _ - _ _ _ _ _ _ - - . _ .

e

k

Post-Event Activities

Corrective Actions .

- - mm rz~ -

_._ _ _ _ _ n n + n s -o**w;--... -

- --

_ _ . _ . . . _ . .

m-=_-  :

. .

Development of Comprehensive Corrective Actions

!

e Leveli PlF

e AIT findings

e 1997 Business Plan analysis

independent Safety Assessment

Past NRC and INPO inspections

i

l

i

!

l

Comed - Zion Station 15

- - - - - - - - - - - - - - _ - - - - - - - - - - - - - - - - - - - _ - - ___

. _ _ _ - _ _ _ _ _ _ - - _ - _ .

t

Post-Event Activities .

Corrective Actions

_ ,; r n : ..m =n.:x .rs.sa _w :1 xgggz;ggg.ggj',7' W'* 7 * "*";R

~

,

Obiectives of Recovery Plan

.

'

.

e Operations performance  !

i

e Plant material condition i

l

.

e Demonstration of plant readiness

L

e Support to Operations

Effective corrective action program

Effective oversight  :

i

. t

Comed - Zion Station 16

i

[

- _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ - _ _ _ _ _ _ _ - _ _ _ _ _ - _ _ _ _ _

_ _ . . _ _ _ _ _ . - _ _ _ _ _ _ - _ _ _ .. __ .

.

Post-Event Activities

.

Corrective Actions

cansm m m m m u m m erre- ,, ,, _ ,;; y e

_

rren -

Operations Performance

Operators

,

o Operations selection process / crew reconstitution 0

e Operations standards

Evolution briefing

Communication

Board awareness

Decorum and formality

o Crew remediaton (Phoenix)

Comed - Zion Station 17

_ - _ - _ - _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ - _ - _ _ - _ _ _ _ - _ - _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - - _ - _ - _ _ _ _ - - _ - _ _ - _ _ _ .

.. . - - . - - _ - - - - _ - - - - . . . - - - - .

,

P

Post-Event Activities -

.

Corrective Actions

- ~=r _ _ _ .= _: ym==~~ i

Operations Performance (continuedD t

Management Support to Operations -

e Defined accountabilities for all Operations positions

.

Clear concise chain of command

Communications flow '

Responsibilities /accountabilities flow q

e Traming '

Permanent program changes ,

e Support for Operation's laaaership role  !

Procedure change process ,

System Engineering and Operations shift interface

i improved Technical Specifications implementation

Professional work spaces

Operations Work Control Center

'

Comed - Zion Station 18 .

i

- - - - - _ _ _ _ . - - - _ _ - - - - _ - _ . - - - _ - _ _ - - - _ _ -

_ - - - _ - - - _.- -.- - - -

[

Post-Event Activities

Corrective Actions  !

.._= x u.w w w wm~ . _. me r - vme

c

n - ~ ~;_,a. ,m }

..r -- .___

Plant Material Condition .

e System affirmations l:

e Reduction in:

.

Work arounds

Control room corrective work i

Open operabilities

Annunciator alarms

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

. _-_____ ___ _-___-___ _-_-____ ___-_-_

___ _ ___ _ ._____ _

,

!  :

Post-Event Activities i

Corrective Actions

= .- ,. _ ,_:_. ~ ~ ~ ~ ~ ~

j Management Demonstration of Plant Readiness

e Plant operational testmg

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

e Verification of site team's support of Operations  :

Identification of issues and communications to management

'

n Correct issues that affect the operators

Getting work done to support Operations

Minimal distractions to the control room  ;

e Performance evaluation review

Comed - Zion Station 20

!

_ _ _ _ _ _ _ . - - - - - _ _ - - _

- . - _ _ _ - - _ _ _ _ - _ _ _ _ _ _ .. - ..

Post-Event Activities

!

Corrective Actions

- ~. __ s., ~

_ _p- =, ,==_

Management Support to Operations for Continuous

'

<

Improvement

-

Timely and Effective Corrective Actions

e Corrective action program improvements .

'

Implement Corporate Corrective Action Program (NSWPs)

increase management involvement - Condition Review Group

Improve corrective action effectiveness - Corrective Action Review Board

Expand root cause analysis training

e Operation experience review

Review previous 5 years of OPEX information

Screen items for evaluation prior to restart

e Department self assessments

Focus support for Operations

Establish critical self assessment capability

Comed - Zion Station 21

.

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _

,

-

Post-Event Activities

Corrective Actions

--__._.,ex-

_

.-.a_- + -

-

maan__

-n _

Management Support to Operations for Continuous

'

Improvement i continued.h

. .

!

!

,

,

Verification of Timely and Effective Corrective Actions

!

e SQV independent assessments

Focused operations assessments

Assess effectiveness of the Recovery Plan objectives

e Safety Review Board oversight

i

e Corporate review and assessment

i

!

Comed - Zion Station 22 .

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ - _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ - _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _

!! , t' 1 :l1 ' l . l l,iil:! ,

.

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__ _ _ _ _ _ _ _ _ _ _ _ ._ _ . _ _

,

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.= 1-> .-.= = _= - -- - Tsi .3MC';f ';,;. ;..

_  :?+z-;;_W]W Qxq M M

.a,-,-. ~ i : wwusa - -_

i

i

i

Nuclear Operating Division

!

Cross-Site Actions  ;

Is

.

E

John Mueller/ Harry Keiser

!

i

t

.

~

.

!

I

Comed - Zion Station 24 i

!

i

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___

t

_-

'l

Nuclear Operations Division

Cross-Site Actions .

_____ m___ i

-mun ~  :-srww.m _ ~

e Operations Performance

i

e Training

!

e Roles and Responsibilities

e Policies  :

!

i

!

!

!

i

i

!

!

l [

Comed - Zion Station 25 i

!

,

_ . _ . _ _ _ _ _ . _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ . _ _ _ _ _ _ _ _ _

. . - . - . - . . - . - . . . . - . - - - . .

!

.

,

-=== _ _ _ ..-,,, _ _

====m -

'

Gas Accumulation in the ~

RCS

George Vanderheyden

Operations Manager - Zio'n Station

'

,

.

.

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

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

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 -

,

Comed - Zion Station 27

'

.

. _ . _ . _ _ _ _ . _ _ . _ _ . _ _ _ _ . _ _ _ _ . _ _ _ _ . _ _ _ . _ _ _ _ _ _ _ _ _ _ . _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

- _--

.

.

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

,

_ _ _ . _ _ _ . _ _ . _ _ . _ _ _ _ _ _ . - _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ . _ _ - _ . _ _

_ _ _ _ _ _ _ _ . _ _ _ _

Gas Accumulation in the RCS ,

Immediate Corrective Actions

---

eerw__ _ _ . _ ___e==--

e Operators informed senior management j

!

i

e A procedure was developed and implemented to vent gas

.

!

e Put RVLIS in service

.

.

i

.

e Lowered VCT pressure

-

e Standing order to vent daily

!

i

!

!

!

Comed - Zion Station 29  !

- - - -- - - -_ -- - - - -- -

. _ _ _. _ _ _ . - _ _ _ _ . _ _ . -

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

eliminate

- Fully effective on Unit 1

- Ongoing accumulation (~10% of original rate) on Unit 2

Same mechanism as September 1996 event

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

Comed - Zion Station 30

'

. . - - - _ _ _ - - _ _ _ _ . . -- . .

Gas Accumulation in the RCS

Gas Accumulation Ana~ Lysis

m y m a c rz. m

-awm3_

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

e Evaluation and implementation of industry information

e Procedure scope

.

e Lack of training on RVLIS use during shutdown

Comed - Zion Station 32

. _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ - _ _ - - _ _ - _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ - - _ _

_ - - _ - _ - - - - _ - - - - _

Gas Accumulation in the RCS

Causal Factors anc Corrective Actions

--m_.=w _, __

mm:m.m emmm-

e Causal Factor

Corrective action follow-up incomplete -

e Corrective Actions

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

eCorrective Actions j

Five year review of past OPEX information

New Operating OPEX staff position dedicated to providing

additional levels of review for-

- Applicability of OPEX, and ,

- Breadth of responsive actions

-

!

i

Comed - Zion Station 34

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ - _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

- _

Gas Accumulation ~in the RCS

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

e Depressurized VCT

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

___--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

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

Becomes self venting  !

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Comed - Zion Station 37

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Gas Accumulation in the RCS -

Reporting - -

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o Comed recognizes the importance of voluntary NRC

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notification for events such as this ,

e Our evaluation determined:

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The event did not actually affect or involve component or train

The event alone could not affect component or train ,

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Comed - Zion Station 38

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Gas Accumulation in the RCS

Closing Remarks

John Mueller

Site Vice-President - Zion Station

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Comed - Zion Station 39

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Technical Specification  ;

Compliance - RCS Flow

Instruments

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George Vanderheyden

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Operations Manager - Zion Station

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Comed - Zion Station 40

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RCS Flow Instruments

Chronology

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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

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Causal Factors

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e Operators did not use Technical Specifications to .

determine Action Requirements j

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Comed - Zion Station 42 -

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RCS Flow Instruments .

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Corrective Actions .

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e Standards clearly define use of Technical Specifications

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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

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Comed - Zion Station 43

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Sa ety Significance

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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

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could occur that would cause a DNB concern at this low power

level

Safety function already performed (trip breakers were open)

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Comed - Zion Station 44

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Closinoo Remarks .

John Mueller

Site Vice-President - Zion Station

Comed - Zion Station 45

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Comed - Zion Station 46

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Enforcement Issues

Summary -

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EEI 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

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Enforcement Issues .

Summary

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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

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Enforcement Issues

Summary

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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.

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Comed - Zion Station 49

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Enforcement Issues

Summary

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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

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Enforcement Issues

Summary

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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

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