ML17174A885

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Safety Insp Repts 50-237/91-22 & 50-249/91-22 on 910629-0822.Violations Noted.Major Areas Inspected:Lers, Operational Safety,Monthly Maint & Surveillance,Training Effectiveness,Sep Items & Safety Assessment
ML17174A885
Person / Time
Site: Dresden  Constellation icon.png
Issue date: 09/11/1991
From: Burgess B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML17174A883 List:
References
50-237-91-22, 50-249-91-22, NUDOCS 9109190066
Download: ML17174A885 (21)


See also: IR 05000237/1991022

Text

U. S. NUCLEAR REGULATORY COMMISSION

REGION II I

Report Nos.

50-237/91022(DRP); 50-249/91022(DRP)

Docket Nos.

50-237; 50-249

License Nos.

DPR-19; DPR-25

Licensee:

Commonwealth Edison Company

Facility Name:

Dresden Nuclear Power Station, Units 2 and 3

Inspection At:

Dresden Site, Morris, IL

Inspection Conducted:

June 29 through Aug~st 22, 1991

Inspectors:

W. Rogers

D. Hills

M. Peck

R. Greger

P. Rescheske

M. Kunowski

N. Shah

. R. Zuffa, Site Resident Engineer

J?-::fi1nois-E:7'~ment of Nuclear Safety

Approved ~~~~

-/,1/9/

By

pro j ~ c ~ s sect i 0 n ~ B

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1

,-,~Ve,.,_e___,__* -

Inspection Summary

from June 29 throu h Au ust 22

1991 (Re ort Nos. 50-237/91022

DRP ;

91

D P .

Areas Inspected: Routine unannounced safety inspection by the resident

inspectors, region based inspectors, and an Illinois Department of ~ucle~r

Safety inspector of licensee acti.on on previously identified items; licensee

event reports; operational safety; monthly maintenance; monthly surveillance;

training effectiveness; Systematic Evaluation Program items; events; safety

assessment and quality verification; and report rev_iew.

Results:

Three cited violations were identified. *One involved the failure of

maintenance workers and their supervision to follow written procedures during

the installation of the steam separator within the reactor vessel.

Another

involved inadequate corrective actions to a previous violatio~ in the area of

NRC reporting.

The third violation dealt with programmatic inadequacies of

the channel check process.

One non-cited violation was identified involving

use of an inadequate procedure by operators while performing radwaste transfer

activities. Five unresolved items and two open items were identified.

One

Systematic Evaluation Program item was closed.

This was Item 14 - Topic*

III-4.5.3 and 2.2.2 (Supp. 1).

9 10919006~ 910912

~DR

ADOC~ 05000237

PDF*<

c

Plant Operations

Management decisions with regard to power ascension and shutdown were

conservative. Operator performance during abnormal and transient conditions *

. was good.

Some weakn~sses were noted in the management directives for

operations regarding NRG reporting, flow control line (FGL) control rod*

  • manipulation instructions, and actions for safety related 4160 VAG bus low

voltage conditions. Also, operators failed to stop and receive additional

instructions on two occasions (FGL situation and radwaste transfer activities)

with adverse consequences.

Finally, management exhibited a significant

increase in awareness towards reporting plant events to the NRG.

M~intenance/Surveillance

Findings associated with the steam separator shroud installation were

reflective of personnel performance weaknesses during the last Unit 2 refueling

outage 10 months ago.

Maintenance actions during this inspection period

appeared adequate except in the reactor recirculation discharge valve initial

root cause determination.

W~aknesses in the content of the surveillance

program persisted and expanded from the previous inspection report period.

Safety Assessment and Quality Verification

.

.

A strength was noted in the reviews conducted by Offsite Review Safety Group

with.their findings considered relevant and a worthwhile contribution to safe

operation. Nuclear Quality Program audits were performance based and beneficial

in identifying problems.

The commitment tracking program for licensee event

report (LER) corrective actions appeared to be adequate.

Conversely, some

weaknesses were noted in the scope of safety evaluations being reviewed by

the offsite review group and in the quality of the post scram review report

for June 9, 1991.

2

.

'

DETAILS

1.

Persons Contacted

  • commonwealth Edison Company
  • Er Eenigenburg, Station Manager
  • L. Gerner, Technical Superintendent *
  • J. Kotowski, Production Superintendent

E. Mantel, Services Director

D. Van Pelt, Assistant *superintendent - Maintenance

J. Achterberg, Assistant Superintendent - Work Planning

  • G. Smith, Assistant Superintendent-Operations
  • K. Peterman, Regulatory Assurance Supervisor

M. Korchynsky, Operating Engineer * *

B. Zank, Operating Engineer

J. Williams, Operating Eng~neer

R. Stobert, Operating *Engineer

T. Mohr, Operating Engineer

  • M. Strait, Technical Staff Supervisor

L. Cartwright, Q.C. S~pervisor .

J. Mayer, Station Security Administrator

D. Morey, Chemistry Services Supervisor

D. Saccomando, Health Physics Services Supervisor

  • B. Viehl, Engineering and Construction
  • F. Kanwischer, Services Superintendent

T. Mohr, Operating Engineer

  • K. Kociuba, Quality Assurance Superintendent
  • D. Lowenstein, Regulatory Assurance Analyst
  • Denotes those attending the exit interview conducted on August 2~, 1991,

and at other time$ throughout the inspection period.

The inspectors also talked wit~ and interviewed several other licensee

employees, including members of the technical arid engineering staffs,

reactor and auxiliary operators, shift engineers and foremen, electrical,

mechanical and instrument maintenance personnel, and contract security

personnel.

2.

Previously Identified Inspection Items (92701 and 92702)

(Open) Open Item (50-237/90027~14(DRP)): Perform sample inspection of

Systematic Evaluation Program (SEP) topic resolutions.

An additional SEP

item confirmed completed by the inspectors is listed in paragraph 8. *

This open item will remain open pending completion of licensee

confirmation of topic closures and completion of the NRC sample

inspection.

(Closed) Violation (50-237/91003-0l(DRP)):

The failure of Dresden

Instrument Surveillance (DIS) 500-9 to adequately prescribe steps to

measure the Reactor Protection System response time in accordance with

Technical Specification requirements.

The inspector reviewed the

3

~--------- --------------------------

.

.

licensee's planned corrective action including rev1s1on of DIS 500-9 to

ensure the proper applications of test equipment.

The inspector

determined that removal of.Dobler timer and the addititin of detailed

procedures are contained in the revised DIS 500-09.

This item is closed.

(Closed) Unresolved Item (50-237/91009-04(DRP)):

Evaluate causal factors

for the March .22, 1991, event involving the lifting of the steam separator

assembly on Unit 2.

On March 22, 1991, Dresden Unit 2 experienced an

unexpected anomaly in electrical power as core flow was increased.

As

coolant flow through the reactor core increased from 72 to 75 ~illiori

pounds per hour, the plant's electrical output increased by 2 megawatts

instead of the anticipated 30 megawatt increase. Also, reactor coolant

temperature .in the annulus region increas~d about 2 degrees Fahrenheit at

the same time the core flow/electrical output anomaly occurred.

Because

the power/flow anomalies were similar to a Vermont Yankee event

associated.with the steam separator lifting. from the seat on the core

shroud in the reactor, the licensee commenced a Unit 2 shutdown on

March 24, 1991, to i~spect the reactor interrials.

An investigation team

comprised of CECo corporate and plant individuals was formed to review

this event, along with other recent maintenance-related problems which

occurred during the Unit 2 refuel outage.

On March 27, 1991, NRC regional _

specialists arrived on site to review the event and licensee actions.

On March 27, 1991, the steam dryer was removed to facilitate the

inspection of the shroud head bolts. With assistance from General

~lectric Company (GE), a detailed inspection plan was initiated and

implemented~ with emphasis placed on verifying if the shroud head bolts

were latched and tightened. Troubleshooting and corrective actions were

performed under work request 000524.

Visual inspections on seven.

accessible shroud head bolts with an underwater camera indicated that the

bolts were latched, but not tightened. Subsequently, all 48 bolts were

verified latched, but not tightened.

In ~dditiqn, several spring

retainers were found to be mis-positioned.

Based on an evaluatton

performed by GE, the loose shroud head bolts would allow the shroud head

and steam separator to lift at high core flow conditions. The GE

analysis for the Vermont Yankee event concluded that no significant

changes in plant safety margins occurred during operation with the steam

separator assembly lifted.

The following conclusions .were based on interviews, observations, and.

document reviews, conducted by NRC regional. inspectors on March 27 -

July 16, 1991:

Steam separator installation was completed during the Unit 2 ~efueling outage

on November 26, 1990, using Work Request 094963 and Dresden Maintenance

Procedure (DMP) 0200-12, "Reactor Shroud Head and Steam Separator

Installation," Revision 7.

A s~cond shift mechanical maintenance crew

-completed the steam separator installation in the reactor cavity, and a third

shift crew (3 maintenance mechanics) completed the latching and

tightening of the separator shroud hold down _bolts.

Based on the signed

steps, in the work package (Steps G.12 and G.15), the third shift foreman

verified the hold down bolts were locked (latched), signed that the hold

down bolt nuts were tightened, independently verified the hold down bolt

4

nuts were tight, and signed that all spring retainers were correctly

positioned up on the nut.

The work crew did not use the procedure wh{le performing the shroud head_

bolt work.

All three mechanics and the foreman indicated that they did

not recall ~eeing the work package during the shift. Workers were not

familiar with having the procedure at the actual job location because

work practices on the refuel floor for mechanical maintenance allowed .the

use of a "clean table for the administrative aspects (signing of steps)

cf the work.

This table was located on the refuel floor; however, away

from the work p.erformed on the refuel bridge.

Review of the procedure by_

the NRC and the licensee indicated that the procedure, although weak, was

adequate and should have resulted in shroud head bolt tightness. Failure

to follow DMP 0200-12 for steam separator shroud bolt locking and

tightening is an example of a violation of 10 CFR Part 50, Appendix B,

Criterion V (50-237/91022-0la(DRS)).

There was no apparent management involvement during the third shift

mechanical maintenance *activities on November 26, 1990.

Because of a

shortage of foremen for that shift, one regular foreman and one upgraded

mechanic were assigned supervisor coverage of the shift's activities.

Normally, three foreman were utilized. Inadequate shift coverage was not

communicated to management.

This lack of supervision resulted in little

observation of maintenance activities on the refuel floor. .Although the

assigned foreman signed the procedure step for tightening the hold down

bolts, he did not observe the work. -The foreman was assigned 5 jobs for

coverage during the shift, with most of his time spent supervising

critical path work performed on the Main Steam Isola_tion Valves.

Dresden

Administrative Procedure. (OAP) 9-11, "Procedure Usage and Adherence,"

Revision 2, Step 0.(3) stated that when a st~p was initialed or signed,

it must be based on either direct observation, er a direct report such as

face to face communication.

If other than direct observation was utiliied,

then the initials of the person performing the observation must be included

with the initials of the person actually initialing the step. Failure to

observe the work or to have any or the three mechanical maintenance crew

members initial the step for the performance of the tightening of the hold

down bolts is an example of a violation of 10 CFR Part 50, Appendix B,

Criterion V (50-237/91022-0lb(DRS)).

All three mechanics had no experience in the hold down bolt tightening,

the proper use of the bolt wrench, or the bolting mechanism.

The 1ead

mechanic recalled experience only with the removal of the separator. The

licensee provided no formal training on th~s bolting process. Training,

usually consisted of "passed down" training from experienced crews.

The

foreman had received informal training as a junior foreman observing the

previous Unit 3 separator installation, but had never actually performed

the work.

Independent verification was not clearly understood by the foreman.

The

cause of this power/flow anomaly clearly indicated that the bolts were

not tightened, or independently verified as tight. After work had been

compl~ted, the lead mechanic and the foreman went to the bridge and the .

foreman "independently verified" the bolt tightness with an underwater

5

telescope.

The tops of the bolts have two flats machined into.them. The

area between the two flats indicated the position of the locking

(latching) T-lugs on the bottom of the bolt assembly.

The foreman

incorrectly used this indication and verified the bolts to be tight.

Bolt tightness could not have been verified in this manner, since the

area in question was located under the shroud lugs.

OAP 9-11,

11Procedure

Usage and Adherencej

11 Revision 2, defined ind~pende~t verification as the

certification of the correctness of an operation or condition based on

eithei first-hand observation or through personally performed

manipulation.

Failure to adequately perform the independent verification

of the shroud head bolt tightness in accordance with OAP 9-11 is an

example of a violation of 10 CFR Part 50, Appendix B, Criterion V

(50-237/91022-0lc(ORS)).

.

The foreman also initialed the procedure step that stated that all spring

- retainers were correctly positioned up to capture the hold down bolt

nuts.

The foreman indicated to both the NRC and the licensee that he did

not know how to actually verify the correct position of the spring

retainers. His visual *verification was based on the fact that the spring

retainers did not appear to be broken and nothing was out of place.

The ~nresolved issue regarding this event is closed; however, one violation

with three examples and no deviations were identified in this area.

3.

Licensee Event Reports Followup (90712 and 92700)

Through direct observations, discussions with licensee personnel, and

revi.ew of records, the following event *report was reviewed to determine

that reportability requirements were fulfilled, immediate corrective

action was accomplished, and corrective action to prevent recurrence had

been accomplished in accordance with Technical Specifications.

(Closed) LER 249i91,;,.004 "Unplanned Standby Gas Treatment System Auto-

start During Calibration

11

(Closed) LER 249/91-003, "Inoperable Torus Wide Range Lever Transmitters.

Due to Unknown Cause".

In addition to the foregoing, the inspector reviewed the licensee's

Deviation reports (OVRsJ generated during the inspection period. This

was done in an effort to monitor the conditions related to plant or

personnel performance, potential trends, etc.

OVRs were also reviewed

for initiation and disposition as required by applicable procedures and

the quality assurance manual.

No violations or deviations were identified except as delineated jn this.

or other reports.

4.

Operational Safety Verification (71707)

During the inspection period the inspectors verified daily, and randomly

during back shift and on weekends, that the facility was being operated

6

. ( c ~ .. ;,: ? .. '

in conformance with the licens*e:and regulatory requirements and that the

licensee

1 s management control<System was effectively carrying out its

responsibilities for safe operation. This was done ori a* sampling basis

through routine direct observation of activities and equipment, tours-of

the facility, interviews and discussions with licensee personnel, reviews

of operating logs, independent verification of safety system status and *

limiting conditiohs for operation action requirements (LCOs), corrective

actiOn, and review of facility records ..

On a sampling basis. the inspectors daily verified proper control .room

staffing and access, operator behavior, and coord.ination of plant *

activities with ongoing control room operations; verified operator

adherence with the latest revisions of procedures for ongoing activities;

verified operation as required by Technical Specifications;

.. :

including compliance with LCOs, with emphasis on engineered safety

features (ESFJ and ESF electrical alignment and valve positions;

monitored instrumentation recorder traces and duplicate channelsfor

abnormalities; verified status of ~arious lit annunciators for operator

understanding, off-normal condition*, and corrective actions being taken;

examined nuclear instr,umentation and other protection channels for

proper operability; reviewed radiation monitors and stack monitors for

abnormal conditions; verified that on~ite and offsite power was available

as required; observed the frequency of plant/control room visits by the *

station manager, superintendents, assistant superintendents, and other

managers; and observed the Safety Parameter Display System for operability.

Iiems for consideration during plant tours included rad1ological controls

adherence, security _plan. implementation, housekeeping controls and

component leakage/lubrication.

As a result of these tours and reviews

these specific occurrences were evaluated:

a.

Torus Widi Range Level Transmitter 3-1641-58 drifted from 14.7 feet

to 13. 5 feet between January 31, 1991 ~ and February 2, 1991. A

similar drop on 3-1641-SA 6ccurred between April .6, 1991, and

May 31, 1991. Operators did not identify these failures until.

June 5, 1991, although the Unit Operator Daily Surveillance Log

(DSL) (Appendix A) required performance of a daily instrument check *

  • on these instruments.

By Technical Specifications definition,

11an instrument check is a

qualitative determination of acceptable operability by observation

of instrument behavior during operation. This determination shall

include, where possible, comparison of the instrument with other

independent instruments measuring the same variable". Initial

op~rator training included only the Technical Specifications

definition and on-the-job training for Appendix A completion from*

licensed Nuclear Station Operators (NSO). .

Specific training involving accuracy for specific instruments in

regard to operability determination had not been given. Although

most of the NSOs appeared to be knowledgeable of the correlation

between the narrow range torus level indicator and the two wide

7

range level indicators, i.e. O" on the narrow range indication

corresponds to 15

1-0" on the wide range indications, they did not

necessarily: use this correlation to perform the operability check.

The Unit Operator DSL (Appendix A) did not provide tolerances, thus

making it difficult for the NSO to assess instrument opera.bility by

m~ans of an instrument check~

NSOs also stated that additional

procedural guidance would be beneficial for performing instrument

checks.

The failure of instruction, procedures, or the Unit Operator DSL

(Appendix A) to provide appropriate acceptance criteria for

performing the instrument check is a violation *

(50-249/91022-02(DRP)) of 10 CFR 50, Appendix B, Criterion V.

In

addition, several operators indicated that they would question the .

operability of these instruments and take appropriate action if they

were indicating at least one foot below the normal expected level of

14.7 feet.

However, the one foot drift did occur and went

unidentified for an exten~ed period.

b.

  • During th~ performance of Dresden Operating Surveillance (DOS) 1400-

04, "Cold Shutdown Testing of the Core Spray System Check Valves",

on July 11, 1991, the 28 core spray pump ran without a suction

source for a short period due to the condensate storage tank

suction valve, 2-1501~37, being in it's normally locked closed

position. Although high vibration was observed, no pump damage was

identified before the pump was stopped.

The failure to open this *

valve prior to performing the surveillance* was due to a deficiency

in DOS 1400-04 that did not prescribe opening the valve.

In

addition, the applicable piping and instrument drawing M-35,

  • Sheet 1, indicated the normal position of this valve as locked open.

Deficiencies regarding the procedure and drawing are considered an

unresolved item (50-237/91022-03(DRP)) pending a review to determine

whether drawing discrepancy was isolated and whether this procedure

had been revised under the procedure upgrade program.

c.

On July 23, 1991, Unit 2 control rods were inserted to reduce the

flow control lin~ (FCL).

The Control Rod Sequence (CRS) for

shutdown enforced by the rod worth minimizer (RWM), did not

correspond to the *first step provided in the* FCL instructions.

Therefore, to use the FCL instructi6ns entailed bypassing the RWM.

Pre~ious management direction had indicated that the RWM would be

left inservice, even at high power levels.

Upon weighin9 the

conflicting directives, the Shift Control Room Engineer (SCRE)

incorrectly instructed the NSO to follow the CRS, resulting in the

insertion of four shaper control rods from step 48 to step 40.

However, the SCRE and NSO did not recognize the possible power

shaping/fuel integrity problems associated with inserting rods per

CRS without first reducing recirculation flow as prescribed in the *

shutdown procedure.

The on-call Qualified Nuclear Engineer (QNE)

was not consulted by the operating crew.

Upon inspection the

following morning, a QNE noted the unexpected rod pattern.

8

Subsequent analysis by the QNE indicated that in this particular case,

power shaping/preconditioning envelope problems did not result. The

operator training program did not specifically ~ddress the importance

and possible adverse reactions to not following the FCL_ instructions.

The day before the event, a licensee initiated reactivity assessment

team had identified .this particular weakness and the ramifications.

This is considered an unresolved item (50-237/91022-04(DRP)) pending

review of the documentation of a licensee reactivity assessment

completed just prior to this event.

d.

On July 23, 1991, large areas of the Unit z and Unit 3 reactor

buildings became contaminated, primarily with Co-60, Mn-54, and Fe-

59, at a maximum of 150,000 disintegrations per minute/100 cm2.

The

contamination was identified after four workers, who had completed

the transfer of spent resin from the Unit 2 fuel pool demineralizer

to a tank in the radwas.te building, alarmed the personnel

contamination monitors.at the main access point to the turbine

building.

Contamination was mainly on their sho~s. Minor

contamination was also found in the turbine building along the path

the worker£ took after exiting the Unit 2 reactor building. Access

to the reactor buildings was restricted during the subsequent

cleanup activities. In addition, an investigation team was formed

by the licensee to determine the cause of the contamination.

Whole-

body counts of personnel who were in the reactor buildings at the

time of the resin transfer identified only one worker with

detectable internal contamination.

The whole-body count for this

individual, who was involved in the transfer~ identified the presence

of 7 nanbcuries of Co-60, a level indicating an exposure to airborne

radioactivity well below regulatory limits.

The licensee's investigation indicated that the fuel pool demineralizer

had not been vented properly prior to backflushing the resin transfer

line after the-resin transfer was completed. Air pressure from the

demineralizer vented via the demineralizer's freeboard drain line

and expelled contamination out of a sample sink drain line, which

  • drained to a common dra i r'I 1 i ne utilized by the demi nera 1 i zer. Spread

of contamination from the sample sink drain to the two reactor building~

was exacerbated because the normal reactor building ventilation was

secured and the lower volume standby gas treatment system was in operation

at the time.

The licensee stated that a similar resin transfer and backflushing

had been done quarterly for several years without similar problems,

but that this time the auxiliary operator did not vent the

demineralizer to atmospheric pressure as had been _done in the past.

The procedure used to transfer resin and backflush, Dresden

Operating Procedure (DOP) 1900-8, Revision 2, "Fuel Pool

Deminer-alizer Resin Transfer,

11 did not contain specific instructions

for venting the demineralizer prior to backflushing. The licensee

indicated that the procedure will be revised to include this

information.

In addition, the licensee indicated that the revised

procedure would prohibit transfers during standby gas treatment

9

operation and that the drain line on the sample sink, which was not

in use, would be sealed. The failure of DOP 1900-8 to adequately

prescribe steps to vent the demineralizer prior to backflushing is

considered to be a violation (50-237/91022-0S(DRSS)) of 10 CFR 50,

Appendix B, Criterion V; however, in accordance with 10 CFR 2,

The procedure revisions and modifications to the sink drain line

will be review~d during a future inspection and is an open item

(50-237/91022-06(bRSS)).

During the review of this incident by the'NRC radiation spectalist,

several minor problems were noted with the ~ont~ol of access to.the

~ontaminated reactor buildings, Although a "contaminated are~" sign

was posted at the double step-off-pad area set up in the narrow

hallway leading into the Unit 2 reactor building, it was not readily

visible. Also survey maps had not *been updated by the start of the

  • day work shift on July 24, 1991, to indicate the-change in

contamination levels in the r~actor buildings.

One individual

entering the reactor building during the day shift on July 24, 1991,

received low level shoe contamination when the step-off-pads were

crossed without recognizing the need for protective clothing. These

matters were discussed with the licensee who agreed to develop a

checklist for use in future contamination events to ensure that all

access control measures are established pro~ptly and adequately.

This checklist will be reviewed during a future inspection and is an

open item (50-237/91022-07(DRSS)).

One cited violation, one non-cited violation and no deviations were

identified in. this area.

5.

Monthly Maintenance Observation (62703)

  • station maintenance activities affecting the safety-related systems_and

components listed below were observed/reviewed to ascertain that they

were conducted in accordance with approved procedures, regulatory guides,

and industry codes or standards and in conformance with Technical

Specifications.

The following items were considered during this review:

the Limiting

. Conditions for Operation were met while components or systems were

removed from service; approvals were obtained prior to initiating the

work; activities were accomplished using approved procedures and were

inspected as applicable; functional testing and/or calibrations were

.

performed- prior to returning components or systems to service; quality

control.records were maintained; activities were accomplished by

qualified personnel; parts and materials used were properly certified;

radiological controls were implemented; ~nd, fire prevention .controls

.were implemented.

Work requests were reviewed to determine status of

outstanding jobs and to assure that priority is assigned to safety- .

related equipment maintenance which may affect system performance .

10

The inspectors monitored the lic~nsee's work in progress and verified

that it was being performed in accordance with proper procedures, and

approved work packages, that applicable drawing updates were made and/or

planned, and that operator training was conducted in a reasonable period

of time.

The following maintenance activities were observed and reviewed:

Unit 2

Recirculation System Sample Valve 220-44 Repair

Shutdown Cooling Loop 2A Suction Valve Control Circuitry Repair

Unit 28 Shutdown Cooling Pump Dtscharge Isolation Valve and Logic Repair

Unit 28 Instrument Air Compressor Overhaul

Unit 3

On1t 3A/3B Hydrogen/Oxygen Monitor Repair

3A Core Spray (CS) Pump Maintenance

3A CS Isolation Valve Rotor Modifi~ations

3A CS Valve Breaker Maintenance

3A & B Post-LOCA Hydrogen/Oxygen Monitor Repair

On Augu~t 6, 1991, the Nuclear Station Operator (NSO) observed the 2A

reactor recirculation pump indicated speed increase to 100%. * While .the

operator was manually reducing pump flow, the 2A pump motor tripped and*

locked out as result of over excitation. Following the pump trip, the

CRAM arrays were inserted to exit from the power/flow instability region.

Investigation determined the pump trip was the result of a failed resistor

in the recirculation motor generator voltage ~egulator circuit.

In

attempting to close the pump discharge valve 2-202-5A to facilitate

returning the idle loop to service, the valve failed to close until the

electrical contactors, at the breaker cubical~ were manually held in. A

drywell entry was made to facilitate a temporary alteration to bypass the

large loading conditions encountered by the valve during a portibr. of the

closing cycle such that the valve could perform its design functfon. *

Further engineering review indicated that the valve torque switch setting

was incorrect and another drywell entry was made to change the setting.

The incorrect setting resulted from valve operation test and evaluation

system (VOTES) testing problems encountered on the valve during the

previous refueling outage. This is considered an unresolved item

(50-237/91022-0B(DRS)) pending further review of the adequacy*of previous

VOTtS testing and the resulting torque switch setting.

No violations or deviations were identified.

6.

Monthly Surveillance Observation (61726)

The inspectors observed surveillance testing required by Technical

Specifications during the inspection period and verified.that testing was

performed in accordance with adequate procedures, that test

instrumentation was calibrated, that LCOs were met, that removal and

restoration of the affected components were accomplished, tha*t results

11 .

c6nformed with Tethnical Specifications and procedure requirements were

reviewed by personnel other than the individual directing the test, and

that any deficiencies identified during the testing were properly

reviewed and resolved by appropriate management personnel.

The*inspectors witnessed portions of the following test activities:

Unit. 2

.

Dos 2300-1,

11HPCI Motor-Operated Valve Operability Verification

11

DOS 2300-3,

11 HPCI System Operability Verification

11

DOS 660.0~2,

11 Unit 2 Diesel Generator Monthly Operability Test

11

Unit 3.

DOS 500-3,

11APRM Rod Block and Scram Functional Test

11

DOS 5600-2,

11Monthly and Weekly Turbine Checks"

The following items*were evaluated:

a.

Technical Specifitation Surveillance 4.7.C.a requires the secondary

containment integrity be demonstrated by drawing a 1/4 inch vacuum

with the standby gas treatment system at each refueling outage.*

During surveillance testing, the secondary containment integrity

acceptance criteria was verified by the averaging of four

different1al pressure (DP) indicators located at the refuel floor.

The inspector identified the calibration of these DP instruments

(DPI-2/3-5741-517, -518~ -519 and -520) was performed without an

approved procedure or specified. acceptance criteria. However, the

inspectors noted that this could be considered another example of a

recent violation (50-237/91016-02(DRP)) and therefore, may be

encompassed by the corrective action regarding that violation.

Subsequent review of the violation response identified that'the

response was not broad enough.

This was discussed in the NRC

response to the licensee's corrective actions and will be pursued

following resolution of the previous violation.

b.

On July 8, 1991, an automatic standby gas treatment system start anp

reactor building v.enti lat ion system i sol at ion inadvertently occurred

during a surveillance on the isolation condenser area radiation

monitor.

Upon identifying the correct cable for the radiation

monitor power supply inside a main control room panel, the

.

instrument technician laid down the procedure.

Upon turning back to

the panel; the technician inadvertently disconnected the cable for

the reactor building fuel pool channel

11A

11 process radiation monitor *

power supply in the same location in the adjacent panel section.

This caused the engineered safety features actuation and was of no

safety consequence.

The technician appeared knowledgeable of the

. procedure and had a momentary lapse of attention to detail and self-

checking.

The instrument technician was counseled and this event

was revi~wed with instrument maintenance department personnel.

The

licensee reviewed component labeling and determined this not to be a

contributing cause .

12

The inspector noted that the ind1vidual involved was not listed on*

the job assignment matrix for this task.

The inspector did*not,

however, consider this a contributing factor to the event.

The

technician had been tr~ined for the task but had not received an on-

the-job training evaluation. This wa~ in accordance with a

  • maintenance department memorandum that allows this if the technician

works under the direct supervision of *the supervisor. The

memorandum defined direct supervision as .observing the critical work

steps as defined by the supervisor.

In this case, no critical steps

were designated due to the supervisor's belief that none existed in

this procedure~ (Only monitors with an alarm and no automatic

actuation function were covered by. this procedure.) The licensee

indicated that a specific definition of critical steps had not been

given in order to give the supervisor more latitud~ based upon

personnel *knowledge of tne technician's abilities. However, the.

licensee did subsequently issue Instrument Department Memorandum 8,

which formalized the determination of critical steps to ensure that

both technician and supervisor were agreed on critical ~tep identification

prior to work performance. Therefore, the inspector has no further

concerns in this area~

.

c.

On August 12, 1990; the licerisee identified deficiencies in Dresden

Instrument Surveillance (DIS) 700-4, "Intermediate Ra~ge Monitor

.

(IRM) Rod Block/Scram Calibration Test", Revision 7, in that th~ IRM

. Hi-Hi and* INOP. functions were not tested adequately to meet

.

  • Technical Specification Table 4.1.1 requirements.

Due to the IRM

Hi-Hi Scram.S.ignal being bypassed when the mode switch was in RUN

and reactor power greater than five percent, the actuation circuitry

was not tested all the way to the scram (107) relays when in this

condition.

In addition, the procedure required the IRM being tested

to be bypassed such that the circuitry would also not be tested to *

the scram (107) relays.

(This was not an immediate safety concern

since these scram functions were automatically bypassed* at the power

conditions the 1.1nits were in at the time of discovery.) The licensee

later discovered similar problems with the source range monitors.* The

liten~ee planned to properly test these functions as soon as appropriat~

conditions were reached. This.is conside~ed an unresolved item

(50-237/91022~09(DRP)) pending revie~ of the test results when the*

circuits are properly tested and, an understanding of hew this

problem was originally discovered.

No violations or deviations were identified.

7.

Training Effectiveness (41400, 41701)

The effectiveness of training programs for licensed and non-licensed

personnel was reviewed by the inspectors during the witnessing of th~

licensee's performante of routine surveillance, maintenance, and

operational activities and during the revie~ of the licensee's response

to events which.*occurred during the inspection period. Except as

indicat~d in paragraph 4.c, personnel appeared to be kn9wledgeable of the

tasks being performed, arid nothing was observed which indicated any

ineffectiveness of training.

13

8.

No violations or devi~tions were identified except as indicated in

paragraph 4. c.

Systematic Evaluation Program (SEP) Items (92701)

NUREG 1403., "Safety Evaluation Report Related to the Full-term Operating

License for Dresden Nuclear Power Station, "Table 2.1, identified 22 SEP

Integrated Plant Safety Assessment Report topic resolutions to be

confirmed by the NRC Region III office.

The following item in that report was confirmed as closed by the

i nsp_ectors:

Item 14 - Topic III-4.5.3 and 2.2.2 (Supp. 1)

Th~ completion for Item 2 for Topic II-3.b.l/4.l.4 is being tracked as

Open Item 50-237/89019-04.

In addition to Item 2, the following two

items remain to be verified as closed by the licensee and confirmed by

the NRC.

Item 13 - Topic III-2/2.2.2 (Supp. 1)

Item 16 - Topic VI-4/4.18.2; Topic VI-6/4.19

Each of these items was in some stage of verification review by the

licensee .

9.

Events Followup (93702)

a.

On July 10, 1991, radiation protection personnel discovered a steam

leak in the reactor water cleanup heat exchanger room in a reactor

recirculati.on sample line. Closure of the recirculation sample line

containment isolation valves (2-220-44 and 45) failed to stop the

leakage.

The leakage path was subsequently isolated by the closure

of a down stream manual valve.

An Unusual Event was declared as

Unit 2 was shutdown due to the containment isolation valve leakage.

The sample line containment isolation valves had previously failed

on March 4, 1990, and February 21, 1991.

The unit was restarted on

July 14, 1991, following repair of the sample line containment

isolation valves.

As-found leakage testing following the shutdown

determined that the total type B and C leakage did not exceed

Technical Specification limits. The vast majority of the leakage

was from the inboard (44) valve due to galling along the seating

surface of the valve plug and seat.

The licensee believed the

galling was caused by maintenance activities while setting the stem

travel or adjusting the valve to reduce its leakage.

Post-

maintenance local leak rate testing did not identify the excessive

leakage since leakage changed with the variation in seating from one

closure to another, depsnding upon how the galled imperfections

happened to align.

Following lapping of the valve seat and

_

machining of the valve plug, special care was taken during valve

reassembly to avoid rotating the plug while it was in contact with

the seat.

The cause of the small amount of outboard (45) valve

leakage was believed to be small surface imperfections on the

seating surface.

14

b.

During the shutdown 6n July 10, 1991, while Unit 2 was. at approximately

300 degrees F and 80 psig, the operator was unable to establish

shutdown cooling (SDC) due to the suction valve cycling closed after

opening the valve.

The SDC valve logic was repaired and shutdown

cooling was established.

The failure was contributed to a poor

wiring connection on the SOC isolation relay. *A second SDC train

was lined up to the fuel pool cooling system and was undergoing heat

exchanger repairs, the third train was unavailable due to the

overhaul of the discharge valve awaiting repair parts. A more

detailed evaluation of licensee shutdown risk management is planned

to be completed during the next inspection period.

c.

At 0116 on August 17, 1991, Unit 3 scrammed during main turbine stop

valve testing.

When opening the number 2 stop valve all six

combined intercept valves closed. Closure of the .combined intercept

valves reduced generator power from 394 MWe (47%) to 25 MWe with

reactor power still at 47%.

Eventually, the reverse power relay

tripped the generator, the turbine ~nd a reactor scram ensued~

The cause of th~ combined intercept valves' closure was a sluggish

fast acting solenoid. valve, which significantly reduced EHC header

pressure. This reduction in header pressure was repeated while

shutdown in special troubleshooting activities. Subsequently, the

  • malfunctioning component was. replaced with acceptable testing

results achieved *

During the scram response operators did not observe the alarm typer

print two seconds after the scram that a *safety related 41.60 volt bus

had low voltage (apprqximately 4000). This was only an alarm typer

alarm without an accompanying annunciator or acknowledgement capability.

The ~pproximately 4000 volt alarm was to trigger operator response to

a recent Electrical Distribution Funcitonal Inspection finding on the

inability of safety related equipment to respond to a degraded grid

condition above the degraded grid relay setting of 3708 volts.

The

operators were to turn on the swing emergency diesel generator

cooling water pump and contact the load dispatcher to increase voltage.

The low voltage condition existed for approximately 1 1/2 hours

before identified by operators and the appropriate actions taken.

The low voltaoe condition was coincident with transfer from the

auxiliary unit transformer to the reserve unit transformer. Also,

at the time of the scram the swing diesel's water pump was being

powered from the Unit 2 power distr.ibution system, which does not

appear to suffer from this same low voltage condition when

transferring to its reserve unit transformer.

The original directive to the operators on this matter did not

consider transient conditions and was inadequate in this respect.

Subsequently, adequate instruction was placed in the scram response

procedure as an operator action to check 4160 bus voltage *

No violations or deviations were identified.

-

15

10.

Safety Assessment and Quality Verification (35502 and 40500)

a.

The inspectots reviewed the post trip investigatiori (PT!) report,

conducted per OAP 7-15, "Scram/Engineered Safety Features (ESF)

Actuation Investigation Program", Revision 3; following the June 9,

1991, reactor scram.

The reactor scram was the direct result of a

high reactor pressure condition following a turbine trip at 42%

power.

The turbine tripped during a test of the thrust bearing wear

  • detector. Following the turbine trip there was an approximate two

minute window, prior to the reactor trip, during which the operator

inserted control rod HB to reduce reactor power and pressure. After

the root cause determination was completed by the licensee, the

inspector interviewed the investigation chairman, participating

operations engirieer, the reactor engineer, and the on-shift NSOs and

SCRE.

The PTI data indicated reactor power was approximately 42% prior to

The plant has a bypass valve capability of 40%

load, plus an addttional 5% for station loads. After the turbine

trip all' the bypass valves opened fully. A loss of feedwater

heating resulted in a positive reactivity insertion and.an increase

in reactor pressure.

In this configuration, the plant was *operating

slightly above the bypass valve capability. After the high pressure

annunciation~ the SCRE directed the NSO to insert control rods.

The

NSO asked the SCRE whether he should use the CRAM arrays or reverse

sequence.

The SCRE directed him to use reverse sequence.

H8 was

the next rod to be inserted per.the control rod sequence.

However,

the reactor scrammed prior to the full insertion of HB.

The PTI contributed the root cause of the event to instrument drift

of the thrust bearing wear detector.

The PTI indicated the scram

could have been prevented if the reactor power was lower

(approximately 300 Mwe).

The PTI did not consider the potential

effect of the use of £RAM arrays or reduction of recirculation flow

as a method to reduce power and avoid the scram.

The omission of

the potential use of CRAM array or recirculation flow reduction in

the PTI root cause investigation is considered a weakness in the trip

investigation report.

In a subsequent interview with operating authority management, the

inspector was informed that another r*eport was to be issued by

September discussing these aspects of the scram.

b.

On July 4, 1991, an automatic closure of two reactor water cleanup

(RWCU) Group III primary containment isolation valves (PCIV)

occurr-ed on Unit 2.

The isolation resulted from a RWCU non-

regenerative heat exchanger high pressure signal following ~ RWCU

pump trip caused by an electrical perturbation while changing the

open position indicating light bulb at the local control station for

the RWCU return valve.

On July 5, 1991~ after senior station

m~nagement reviewed the event during a routine planning meeting, the

determination was m~de that the automatic closure of the PCIVs did

. 16

constitute an ESF actuation.

The station subsequently made the

required NRC notification about 17 hours1.967593e-4 days <br />0.00472 hours <br />2.810847e-5 weeks <br />6.4685e-6 months <br /> after the event.

ESF

actuations are required to be reported to the NRC within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />

per. 10 CFR 50.72(b)(2){ii).

A previous violation of 10 CFR 50.72(b)(2)(ii) was issued

(50-237/90027-06(DRP)) for failure to make the four hour NRC

notification following an unplanned automatic clos~re of eight PCIVs

on December 8, 1990.

In response to the Notice of Violation, the

licensee issued a memorandum to the on-shift operating authority to

provide guidance on the definition of an ESF actuation. The

guidance defined an ESF actuation to fnclude any unplanned or

unknown occurrence involving the actuation of an ESF train~ which

results in the completion of desired repositioning of any pieces of

equipment.

However, in neither the December 8, 1990, nor the *

July 4, 1991, events, did the PCIV logic initiate. Both events

involved only the actuation of the end device.

NUREG-1022, Licensee

Event Report System, Supplement No. 1,Section II.6, clarified that

an ESF actuation includes any automatic, spurious, or manual *action

that results in the actuation of the device to perform its intended

function.

In both events, the intended ESF safety function was the

automatic closure of the PC!Vs.

.

'

Th~ inspector's interview determined.that the SCRE believed the

closure of the PCIVs did constitute ~n valid ESF actuation signal at

the time of the event. However, after consulting with off-shift

management, the decision was made. not to make the NRC notification.

This decision was based upon th~ closure initiation signal not

driven by the primary containment isolation system .. The SCRE was

unaware of the guidance provided in NUREG-1022 or the operations

memorandum *. Additionally, the SCRE had not receive any additiona 1

training on reportability and was unfamiliar with the December 8,

1990, event.

The Shift Engineer (SE) did review the operations

memorandum during the reportability evaluation process.

However,

the "guidance~ provided in the memorandum was confusing and the SE

concluded an ESF actuation did not occur *

. The failure to provide adequate corrective actions to prevent

recurrence of the previous violation is considered a violation of

(50-237/91022-lO(DRP)) 10 CFR 50, Appendix B, Criteria XVI.

c. *The inspectors performed an evaluation of the licensee's quality

assurance program implementation. This involved a review of the

licensee's Nuclear Quality Program (NQP) assessments and

surveillances, and Offsite Nuclear Safety Group functions. A

similar review of Onsite Nuclear Safety Group functions was

described in Inspection Report 50-237/91016(DRP);

~0-249/91016(DRP}.

The inspector reviewed NQP audit reports and verified that

~ppropriate corrective actions to findings were delineated and were

being tracked by both NQP and the plant Nuclear Tracking System (NTS).

17

Findings were assigned a status level that would change to ensure

greater management scrutiny if adequate corrective action *

implementation progres~ was not being accomplished. *In addition,

items greater than 60 days old were flagged in a special report.

Previous finding_s were also .incorporated into subsequent audits to

evaluate the effectiveness of completed corrective actions. Audit

planning was considered good in that related documents events and

personnel were reviewed and/or interviewed to identify specific

audit items.

In.addition, problems identified at other plants were

reviewed for inclusicin such as the Zion Diagnostic Evaluation Team

issues.

The inspector's review of specific findings determined the

licensee's shift to performance based audits to be beneficial in

identifying implementation problems.

Recent improvements in

tracking capabilities were also being utilized to identify problem

areas and to redirect resources. In addition to scheduled audits, *

special audits were performed.in suspect areas. The inspector noted

that team assessments previously conducted in different area~ at

various times during the year, were combined into one large yearly

assessment of a 11 areas conducted in January 1991.

Staffing levels

for the on~ite NQP group appeared adequate with individual

backgrounds from varying areas to ensure the ability _to provide

informed coverage of many disciplines.

Two of the thirteen onsite

NQP personnel were Seriior Reactor Operator (SRO) licensed and two

were SRO certified.

The Offsite Nuclear Safety Group (OFSG) responsibilitie_s were

delineated in Technical Specification 6.1.G.

The inspector regarded

recent OFSG findings and issues to be both relevant and a worthwhile

contribution toward safe plant operation.

However, the inspector

noted that safety evaluations for certain classes of procedures were

not being routed to the OFSG for review in accordance with the

requirements of Dresden Administrative Procedure (OAP) 9-02),

"Procedure and Revision Processing

11

, Revision 24, Step F.7.c.(4).

This.OAP had been previously changed in response to an early 1990

NQP finding of a similar nature, to require procedures which have a

completed Safety Evaluation Form 10-2C to be transmitted to OFSG.

In addition, the inspector noted that an OFSG review dated

October 1, 199Q, (OFSG Tracking No. 12-90-204) indicated that the

Unit 2 high pressure coolant injection (HPCI) steam line high flow

isolation differential pressure transmitter had not been calibrated

in two years and that no surveillance requirement existed.

The OFSG

participant for Dresden indicated that a review had been conducted for

similar instrument calibration problems but that none were identified.

Suggested corrective actions appeared specific to this type instrument.

A more generic issue* involving numerous instruments inappropriately

omitted from periodic surveillance calibration requtrements was

subsequently identified by the NRC and was the subject of a previous

vi6lation (50-237/91016-02(DRP)). Actions in response to the

previous OFSG issue did not identify the generic nature of the

18.

. .

'*

d.

.,

i .*.

finding.

Both these issues are considered to be an unresolved item

(50-237/91022-ll(DRP)) pending completion and review of the

licensee

1 s. root cause analysis of the first corrective action

deficiency and further review of licensee actions regarding the

second.

The inspector noted that coordination of improvement fnitiatives

improved by the addition of an individual reporting directly to the

Jechnical Superintendent. This individual was responsible for

.development of the Dresden Management Action Plan including ensu~ing

timely implem~ntation of planned activitiei.

The inspector reviewed the licensee's tracking and resolution-of LER

actions *to *ass~ss managements effectiveness in this area.

The LERs

were reviewed for the nature of the event, the proposed corrective

action, the assignment qf .NTS.corrective action numbers, and the

overall abilityto consistently track.and update the status of

corrective action items.

Additional reviews included evaluation of

the adequacy of periodic updates on outstanding corrective actions

along with the length of time that specific corrective action items

  • .remained open* or unresolved.

Of the seventy-one items reviewed, two

. ~ -

problems were noted:

LER 237/83-062 involved th~ Unit 2 HPCI motor gear unit (MGU)

which was observed to have been oscillating between the high

and low speed stops without operator action during a scheduled

HPCI surveillance test. Corrective action delineated in the LER

was tq modify the HPCI control system (Modification M12-2-83-54).,

which would replace the MGU signal converter containing a sensitive

operational amplifier and move the new amplifier to a less harsh

environment.

Latest up-dated corrective action as reported under

the NTS corrective action summary indicated that the modification

for replacement and relocation of the MGU signal conv~rter had

been canceled.

Nb notification to the NRC had been made in

regard to the change in LER corrective action commitme~ts.

Once identified to the licensee, the licensee stated that. a

r~vised LER would be submitted discussing the rational for

cancellation.of the modifi~ation.

An excessive implementation period was ideniified for the

corrective action itefus asso~iated with LER 237/88~013. LER

(237/88-013) resulted from a loss of power to an Analog Trip

System M~ster Trip Unit.

An outstanding commitment, resulting* .

from the corrective actions, involved the development of a

refetence guide.in order to determine the components affected

when fuses were removed from circuit panels.

The guide would

be an instructional tool for removing fuses *

Once identified to the l~censee, th~ guide w~s completed and

was in the procedure review cycle by the end of the inspection

period.

One viola.tion .and no deviations. were identified in this area.

19

11 *. Report Review

During the inspection period, the inspector reviewed the licensee's

Monthly Operating Report for July 1991. The inspector confirmed that the

information provided met the requirements of Technical Sp~cification

6.6.A.3 and Regulatory Guide 1.16. The inspector also reviewed the

Dresden Nuclear Power Station Monthly Plant Status Report for June 1991.

No* violation$ or deviations were identified.

12 *. Violations For Which A "Notice of Violation" Wi 11 Not Be Issued

The NRC uses the Notice of Violation as a standard method for formalizing

the existence of a violation of a legally binding requirement.

However,

because the NRC wants to encourage and support licensee's initiative~ for*

self-identification and correction of problems, the NRC will not

generally issue a Notice of Violation for a violation that meets the

requirements set forth in 10 CFR 2~ Appendix C,Section V.A.

A violation

of regulatory requirements identified during the inspection for which a

Notice of Violation will not be issued is discussed in paragraph 4.d.

13.

Unresolved Items

Unresolved items are m~tters which require more information in order to

ascertain whether it is an acceptable item, an open item, a deviation or

a violation. Unresolved items disclosed during this inspection are.

discussed in paragraphs 4.b., 4.c., 5, 6.c., and 10.c.

14.

Open Items

Open items are matters which: have been discussed with the licensee;

will be further reviewed by the inspector; and whiCh involved some actions

on the part of the NRC, licensee, or both.

Two open items disclosed

during th inspection are discussed in paragraph 4.d.

15.

Exit Interview

lhe inspectors m~t with licensee representatives (denoted in paragraph 1)

during the inspection period and at the conclusion of the inspection

period .on August 22, 1991.

The inspectors summarized the scope and

results of the inspection and discussed the likely content of this

inspection report.

The licensee acknowledged the information and did not

indicate that any of the information disclosed during the inspection

could be considered proprietary in natur~.

20

Docket No. 50-237

Docket No. 50-249

Commonwealth Edison Company

ATTN:

Mr. Cordell Reed

Senior Vice President

Opus West II I

1400 Opus Place

Downers Grove, IL

60515 *

Dear Mr *. Reed:

This refers to the routine safety inspection conducted by W. Rogers, D. Hills

M. Peck, R. Greger, P. Rescheske, M. Kunowski and N. Shah of this office and

assisted by R. Zuffa of the Illinois Department of Nuclear Safety on June 29

through August 22, 1991, of activities at Dresden Nuclear Power Station, Units

2 *and 3 authorized by NRC Operating License Nos. DPR-19 and DPR-25 and to the*

discussion of our findings with Mr. E. Eenigenburg and others at the

conclusion of the inspection.

The enclosed copy of our inspection report identifies areas examined during

the inspection. Within these areas, the inspection consisted of a selective

examination of procedures and representative records, observations, and

interviews wtth personnel.

During this inspection, certain of your activities appeared to be in violation

of NRC requirements, as described in the enclosed Notice. A *written response

is required.

However, because the NRC wants to encourage and support

licensee's initiatives for self-i~entification and correction of problems, the

NRC will not gen~rally issue a Notice of Violation for a violation that meets

the requirements of 10 CFR 2, Appendix C, Section V.A.

This is the case with

the violation discussed in paragraph 4.d of the enclpsed inspection report.

If you do not agree with our statement of your corrective actions, you are

requested to inform us, in writing, within 30 days of the date of th.is le.tter.

Otherwise, no reply to the violation is required and we have no further

questions regarding this matter at this time.

In accordance with 10 CFR 2.790, of the Commission's regulations, a copy of

this letter and the enclosure(s) will be placed in the NRC Public Document

Room.*

The responses directed by this letter (and the accompanying Notice) are not

. subject to the clearance procedures of the Office of Management and Budget as

required by the Paperwork Reduction Act of 1980, PL 96-511.