ML20234D600

Insp Rept 50-454/87-22 on 870526-0612.Apparent Violations Noted:Entry Into Mode 4 W/Inoperable Spray Additive Sys & Failure to Place Unit in Mode 5 W/Inoperable Spray Additive Sys

ML20234D600
Person / Time
Site:	Byron
Issue date:	06/24/1987
From:	Hinds J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20234D590	List: ML20234D588 ML20234D600
References
50-454-87-22, NUDOCS 8707070272
Download: ML20234D600 (7)

See also: IR 05000454/1987022

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U. S. NUCLEAR REGULATORY COMMISSION

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REGION III

Report No.50-45U 87022(DRP)

Docket No. 50-454

License No. NPF-37

Licensee: Commonwealth Edison Company

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Post Office Box 767

Chicago, IL 60690

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Facility Name:

Byron Station, Unit 1

Inspection At: Byron Station, Byron, IL

Inspection Conducted: May 26 - June 12, 1987

Inspector:

P. G. Brochman

J. M. Hinds, Jr.

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Approved B

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MV//7

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Reactor Projects Section IA

Date

Inspection Summary

Inspection on May 26 - June 12, 1987 (Report No. 50-454/87022(DRP))

Areas Inspected:

Special, unannounced safety inspection by the resident

inspectors to review the circumstances surrounding the inoperability of both

trains of the spray additive (sodium hydroxide) portion of the Unit 1

containment spray system.

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Results: One apparent violation of NRC r3quirements was identified: (entry

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into Mode 4 with an inoperable spray additive system and failure to place

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the unit in Mode 5 with an inoperable spray additive system).

This apparent

violation is of safety significance and had the potential to affect the

public's health and safety.

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8707070272 870629

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DETAILS

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Persons Contacted

Commonwealth Edison Company

R. Querio, Station Manager

• R. Pleniewicz, Production Superintendent

R. Ward, Services Superintendent

W. Burkamper, Quality Assurance Superintendent

• L. Sues, Assistant Superintendent, Operating

G. Schwartz, Assistant Superintendent, Maintenance

• T. Joyce, Assistant Superintendent, Technical Services

J. Schrock, Operating Engineer, Unit 1

• M. Snow, Regulatory Assurance Supervisor

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F. Hornbeak, Technical Staff Supervisor

• E. Zittle, Regulatory Assurance Staff

• G. Stauffer, Assistant Technical Staff Supervisor

• R. Williams, Technical Staff

• W. Pirnat, Regulatory Assurance

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• H. Erickson, Maintenance Staff Assistant

• J. Langan, Regulatory Assurance

The inspector also contacted and interviewed other licensee and

contractor personnel during the course of this inspection.

• Denotes those present during the exit interview on June 12, 1987.

2.

purpose

This inspection was conducted to review the circumstances surrounding the

loss of control of two locked valves, IC5018A and ICS018B, in the spray

additive [ sodium hydroxide (Na0H)] portion of the Unit I containment

spray (CS) system.

Valves ICS018A and ICS018B were found shut, instead

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of locked open, during a NRC verification of the CS system operability.

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With these valves shut both trains of the spray additive system were

physically inoperable from May 2 - 26, 1986.

3.

Description of the Event

On May 1,1987, a request was made to revise Byron Operating Procedure B0P

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CS-S, " Containment Spray System Recirculation to the RWST," to provide

additional assurance that the Na0H tank would be isolated from CS system

during recirculation so that the NaOH would not contaminate the RWST

(Refueling Water Storage Tank). This was the result of experience at

the licensee's Zion Station. To accomplish this, temporary change number

87-0-688 was issued to modify B0P CS-5 and steps were added to the

procedure to shut additional valves in the line from the Na0H tank to

the CS eductors (ICS018A and ICS0188) and to drain the Na0H remaining

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in the piping. Steps to restore valves ICS018A and ICS018B to the locked

open position were included in the temporary change.

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On May 2,1987, operating department personnel performed Byron Operating

Surveillance IBOS 6.3.2.b-1, " Phase B Containment Isolation, Containment

Ventilation Isolation, and Containment Spray Actuation by Manual

Initiation." Step F.1.2 requires that the CS system be aligned for

operation per B0P CS-5.

Valves ICS018A and 1C50188 were unlocked and

shut. The surveillance was successfully performed; however, the BOS

provided its own directions for system restoration and did not direct a

return to B0P CS-5; consequently, valves ICS018A and 1C5018B remained

shut until they were discovered to be incorrectly positioned on May 26,

1987 and were subsequently locked open.

4.

Chronology of Events

4/22/87

The valve lineup for the CS system, 80P CS-M1, is completed and

valves 1CS018A and ICS018B are verified to be locked open.

5/01/87

Temporary change 87-0-688 is issued to B0P CS-5 to shut valves

ICS018A and 105018B to prevent Na0H contamination of the RWST

when the CS system is recirculated to the RWST.

Instructions

to realign valves ICS018A and 105018B to their proper position

for system restoration are also provided.

5/02/87

Surveillance 180S 6.3.2.b-1 is performed and step F.1.2 directs

that the CS system be aligned for recirculation per BOP CS-5.

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Valves ICS018A and 1C5018B are unlocked and repositioned shut.

The surveillance is completed and section 6 of the BOS provides

its own restoration instructions and the need to reposition

valves ICS018A and 1C5018B is not recognized. With these

valves shut the Na0H tank was isolated from the CS system

eductors.

5/06/87

At 0900 the unit entered Mode 4 with both trains of the spray

additive system inoperable, contrary to Technical Specification 3.0.4.

5/12/87

By 1500 the spray additive system had been inoperable for 120

hours and action was not taken to place the unit in Cold

Shutdown [ Mode 5] within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />, contrary to

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Technical Specification 3.6.2.2.

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5/15/87

At 1412 the unit entered Mode 5 for unrelated reasons

(maintenance) approximately 221 hours0.00256 days <br />0.0614 hours <br />3.654101e-4 weeks <br />8.40905e-5 months <br /> after entering Mode 4.

5/23/87

At 1343 the unit again entered Mode 4 with both trains of the

spray additive system inoperable, contrary to Technical Specification 3.0.4.

5/26/87

At approximately 1655 valves ICS018A and ICS018B were

discovered to be unlocked and shut during a NRC walkdown of

the CS system.

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5.

Evaluatic,n of the Event

The Byron FSAR, Section 6.5.2 states that the CS system is designed to

remove fission products, nrimarily elemental iodine, from the containment

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atmosphere for the purpose of minimizing the offsite radiological

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consequences following a design-basis loss-of-coolant-accident [LOCA].

Section 6.5.2.1 states, in part, that the CS system is designed tn remove

sufficient iodine from the containment atmosphere to limit, in the event

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of a LOCA, the offsite and site boundary doses to values less than the

limits of 10 CFR 100. The spray additive system adds Na0H via the CS

system eductors to change the pH level of the water in containment.

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Section 6.5.2.1 discusses the failure of one of the trains of the spray

additive system and states, in part, that even with a single failure

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sufficient Na0H is added to the water in containment sump to form a 8.55

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pH solution, when combined with the spilled reactor coolant system water

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and the water from the safety injection systems. This pH is necessary to

attain an iodine portion coefficient greater than 4E+3 which will result

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in a decontamination factor of 100 in the containment atmosphere.

With valves ICS018A and 1050188 shut, both of the trains of piping from

the Na0H tank ta the CS system eductors were isolated and the spray

additive system was physically inoperable.

However, the rest of the CS

system was operable and could have sprayed water into containment had the

system been actuated.

Technical Specification 3.0.4 requires that entry into en operational

mode shall not be made unless the conditions for the Limiting Condition

for Operation are met. Technical Specification 3.6.2.2 requires that the

spray additive system shall be operable in modes 3 and 4 with a spray

additive eductor capable of adding sodium hydroxide (NaOH) to a

containment spray system pump flow. With the spray additive system

inoperable, restore the system to operable status within the next 120

hours or else be in Cold Shutdown [ Mode 5] in the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

For the

spray additive system to be operable, valves ICS018A and 1C5018B must be

open, so that NaOH can flow from the storage tank to each of the spray

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additive eductors, when the containment spray system is actuated.

On May 6, 1987, and May 23, 1987, Unit 1 entered Mode 4 with valves

ICS018A and 1C5018B shut rendering the spray additive system inoperable.

The failure to have an operable spray additive system upon entry into

mode 4 is an apparent violation of Technical Specification 3.0.4

(454/87022-01a(DRP).

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From 0900 on May 6, 1987, to 1412 on May 15, 1987, [221 hours] Unit I

was in Modes 3 and 4, and valves ICS018A and 105018B were shut for

greater than 120 hours0.00139 days <br />0.0333 hours <br />1.984127e-4 weeks <br />4.566e-5 months <br /> rendering the spray additive system inoperable.

The failure to place the unit in Mode 5 within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> is an

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apparent violation of Technical Specification 3.6.2.2

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(454/87022-01b(DRP).

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6.

Corrective Actions Initiated by +.he Licensee

a.

The licensee verified that the remaining valves in the Unit 1 CS

system were in their correct position, exceot 1C5045, which was

locked open instead of locked shut. The required position for valve

1CS045 had been changed by a modification and the valve lineup

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procedure revised, but the valve had not been repositioned. The

licensee verified that the valves in the Unit 2 CS system were in

their correct position.

b.

The licensee revised Byron Administrative Procedure BAP 1310-4,

" Temporary Changes to Permanent Procedures," to require that when a

temporarily changed procedura is used in conjunction with other

procedures, the temporary changed procedure must reference the other

procedure and the safety review must examine any interactions

between the two procedures.

If the other procedure is not.

referenced on temporary change form, a new safety review will have

to be performed on the combined use of these procedures, before the

procedures can be used together.

c.

The licensee has revised the locked equipment program to require

that all changes from the normal position for a locked component

be documented on the kcked equipment deviation log, BAP 330-3T1.

Previously surveillance procedures were exempt from this

requirement. A time limit on how long an abnormally positioned

locked equipment can remain in that condition will be indicated on

thelockedequipmentdeviationlog(e.g...aspecificdate, Mode

change, or some other milestone).

d.

The licensee has installed a temporary status board to track all

unlocked components. The information contained on the status board

consists of the:

component name, date unlocked, date required to be

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returned to service, and reason why component is unlocked.. This

temporary status board will be used until the changes described in

paragraphs e and f below are in place.

e.

The licensee is changing the present system of locks used in the

locked equipment program from.five different cores (trd n 1A, IB,

2A, 2B, and common equipment) to individually keyed locks for the

approximately 600 components in the program.

Presently a "B1" key

could open any locked valve in Unit 1 on an "A" train component, be

it a 1A auxiliary feedwater, diesel generator, or containment spray

valve.

Master keys will be available to the operators for use in

emergencies. Until these changes are completed all "B" series keys

are being stored in a locked container and the shift supervisor must

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authorize the issuance of the key.

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f.

The licensee intends to create a new status board to hold each of

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the approximately 600 new keys. A status board will be created

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with a place for each of these 600 keys. The status board will be

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designed so that it will be easy to inventory the keys present and

it will be readily apparent when a key has been removed. A review

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of the new locked equipment status board will be added to the mode

change checklists.

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Conclusion

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This event has indicated significant weaknesses in the licensee's program

for the control of locked equipment.

The application of the locked

equipment deviation log and of other requirements specified in the locked

equipment program (BAP 330-3) to procedures other than surveillance was

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not consistent. Additionally, paragraph C.I.e of BAP 330-3 requires that

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when a piece of equipment is unlocked, the lock and chain are to be

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securely fastened. When the valves were found, the locks were not

secured as required by the BAP.

The inspector reviewed several operating procedures for other

safety-related systems (Auxiliary Feedwater, Diesel Generator, Spent Fuel

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Pool Cooling, and Safety Injection) which unlocked valves and determined

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that no mention of BAP 330-3 nor the locked equipment deviation log BAP

330-3T1 was made. A review of several Residual Heat Removal (RH) system

. operating procedures showed that the locked equipment program and locked

equipment deviation log were referenced; however, the number of the

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referenced procedures had been deleted over one year ago and in fact had

been deleted before the current revision of the RH procedures were

issued.

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Problems were indicated in the review of changes to procedures when the

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changed procedure may be used, in part, by other procedures. Barring

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some type of computerized crossreference system the inspectors are unsure

if this problem would have been caught in a normal procedure review. As

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a result the licensee needs to evaluate the use of stand alone procedures

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or using the same procedure to align equipment for testing and then

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realign the equipment for operation using the same procedure.

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The safety significance of the inoperable spray additive system is

mitigated by several facts. The unit was in Mode 3 after a shutdown of

approximately 80 days, reducing the energy present in the core to drive a

release. The iodine inventory present in the core was reduced by its

decay following the shutdown.

Had a containment spray actuation occurred

during this time period, the operators in the control room would have had

indication of Na0H flow and NaOH tank level. Additionally, a low Na0H

flow alarm is installed in the control room.

Consequently, operators

could have been dispatched to repair the malfunctioning spray additive

system on a containment spray actuation.

As a result of this problem redundant trains of a safety-related system

were simultaneously inoperable. The NRC has serious concerns with the

licensee's performance in the area of safety-related system operability.

In the last two years there have been four previous events (three events

within the last six months) in which redundant trains of safety-related

system were simultaneously inoperable (both trains of Residual Heat

Removal inoperable during various times between March and July 1985; both

trains of Safety Injection inoperable in December 1986; both trains of

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the Essential Service water makeup pumps in February 1987; and two of

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three required trains of the non-accessible area exhaust filter plenum in

February 1987). The NRC recognizes that the root causes for these events

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were different; however, the overall affect on safety-related system

operability is considered unacceptable. The NRC is concerned that taken

together these events are indicative of inadequate performance by

licensee management in ensuring operability of safety-related systems.

8.

ExitInterview(30703)

The inspectors met with licensee representatives denoted in Paragraph 1

at the conclusion of the inspection on June 12, 1987. The inspectors

summarized the purpose and scope of the inspection and the findings.

The inspectors also discussed the likely informational content of the

inspection report with regard to documents or processes reviewed by the

inspectors during the inspection. The licensee did not identify any such

documents or processes as proprietary.

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