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Insp Rept 50-271/88-04 on 880208-11.Violations Noted.Major Areas Inspected:Licensee Effort to Comply w/10CFR50,App R Requirements Re Fire Protection Features to Ensure Ability to Achieve & Maintain Safe Shutdown
	ML20151C709
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	04/01/1988
From:	Krasopoulos A; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:	;
Shared Package
ML20151C684	List: ML20151C682; ML20151C703; ML20151C709;
References
	50-271-88-04, 50-271-88-4, NUDOCS 8804130142
	Download: ML20151C709 (18)
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). U.S. NUCLEAR REGULATORY COMMISSION !

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REGION I

Report No. 50-271/88-04

j Docket No. 50-271 :

j License No. DPR-28 Priority -- Category _C_

Licensee: Vermont Yankee Nuclear power Corporation ,

Facility Name: Vermont Yankee

Inspection At: Vernon. Vermont l

l Inspection Conducted: February 8-11,-1988

J Inspector: CAk d rage //U

~A.VKras6)ou os, Reactor Engineer date

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Also participating in the inspection and contributing to the report were: )

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R. Hodor, Mechanical Systems Specialist, BNL

K. Sullivan, Electr Systems Specialist, BNL

Approved by: C)

C. J.(/ Anderson, Chief, Plant Systems

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Section, DRS

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Inspection Summary: Inspection on February 8-11, 1988 (Report No. 50-271/88-04)

Areas Inspected: Special, announced team inspection of the licensee's effort .

to comply with the requirements of 10 CFR 50, Appendix R, Section III. G, J .!

and L concerning fire protection features to ensure the ability to achieve and l

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maintain safe shutdown. l

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l Results: The team verified that the licensee is in compliance with the !

requirements of 10 CFR 50 Appendix R. The licensee has an analysis and a !

program assuring separation of safe shutdown trains. This separation will i

assure that in the event of a fire, one safe shutdown train will remain i

available to shut the plant down. The team identified one violation of the

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requirements and four items remained unresolved. The violation stems from the )

failure to install emergency lights in plant areas requiring shutdown actions. ,

With regard to the unresolved items, one item is a commitment to install fire I

retardant on electrical cables traversing the combustible free zones. The l

other three unresolved items in'/olve commitments to upgrade and document l

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portions of the associated circuit analysis. These analyses will be completed i

180 days upon receipt of this report, j

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DETAILS

1.0 Persons Contacted

1.1 Vermont Yankee Nuclear Power Corporation (VY)

J. P. Pelletier, Plant Manager

J. K. Thayer, Engineering Manager

E. A. Sawyer, Manger of Engineering Services

R. Moschella, Sr. Engineer

T. White, Project Engineer

0. Girroir, Sr. Engineer

P. Johnson, Sr. Electrical Engineer

H. Metell, Engineering Support Supervisor

R. D. Pagodin, Technical Services Superintendent

G. J. LeClair, Assistant Operations Supervisor

E. Taintor Jr., QA Coordinator

M. Sontag, Operations Training Instructor

M. Bronson, Sr. Control Room Operator

J. Desicets, Shift Supervisor

S. Jefferson, Assistant and Plant Manager

R. Swenson, Sr. Engineer

0. Phillips, Sr. Electrical Engineer

A. Klein, Fire Protection Engineer

R. January, Sr. Electrical Engineer

0. Reid, Operations Superintendent

1.2 U.S. Nuclear Regulatory Commission (NRC)

G. E. Grant, Senior Resident Inspector

J. B. Mcdonald, Resident Inspector

Denotes those present at the exit interview.

2.0 Follow Up of Previous Inspection Findings

(Closed) Violation (83-26-01) Multiple Instances Where the Separation

Requirements of Appendix R Section III G Were Not Met

The NRC in an inspection conducted on August 29-September 2, 1983

identified examples of violations of the 10 CFR 50 Appendix R

requirements. They are as follows:

a) The licensee did not provide the required protection to redundant

trains of systems (cable trays from both divisions) located in the

northwest corner of the Reactor Building (RB).

b) The licensee did not provide adequate separation for the redundant

control cables of the HPCI and RCIC inboard isolation valves V23-15

and V13-15, respectively,

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c) The licensee did not provide adequate separation and protection for

the redundant safe shutdown related Motor Control Centers (MCC) 89B

and 90 in that the 20 feet combustible free zone separating them

contained combustibles in the form of open cable trays and did not

have a means of suppression,

d) The licensee did not provide suppression and detection for the

redundant instrument rack located at elevation 280' East RB.

e) The licensee did not provide suppression and detection for the

redundant MCC 88 and 9B in the personnel monitor of the RB.

Since these violations were identified the following corrective actions

were implemented by the licensee:

For Item a), the licensee installed additional suppression in the area

above the cable trays. This would assure that a fire in one cable

division would not propagate to the redundant division about 20 feet ;

away. In addition, detection was provided throughout the zone. These l

modifications were completed on February 2, 1985. The inspector verified

that the installation of the sprinkler and detection systems meet the !

NFPA standards. '

For Item b), the licensee rerouted conduit 1118BJSIIX, RCIC Control Cable l

and provided an alternate power supply to the inboard isolation I

valve V13-15. The inspection verified that the modifications were

implemented and that the proper separation exists between the cables of I

the redundant RCIC and HPCI systems. l

For Item c), the licensee provided component separation by relocating

the power supply to V13-15 from MCC 898 at elevation 262' to MCC 89 at

elevation 280' RB south side. In addition, an alternate power supply

was provided for this valve at MCC 9B located at elevation 280' north

side. The net effect of this change is the RCIC and HPCI inboard

isolation valves cables are not in the same fire zone precluding damage

to simultaneous loss of both HPCI and RCIC from a fire in this area.

For Item d), the licensee installed detection in the area of the

instrument racks. This work was completed on August 8, 1987. The

licensee also requested relief from the requirement to install suppression

in the area of the instrument racks. The NRC in a Safety Evaluation

Report (SER) dated December 1, 1986 granted the licensee an exemption from

the requirement to install suppression in the area.

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For Item e), the licensee protected the cables with a 3 Hour fire wrap.

This work was completed on August 8,1987. The inspector reviewed the

work performed by the licensee in response to the violation and found

that the corrective actions are adequate.

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This item is resolved.

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(Closed) 83-26-03.(Inspectio, Follow Up Item) Revision of the 5

Service Water / Alternate Cooling Operating Procedures 6

i This item identified the concern that certain procedure steps were not

! grouped together such that the operators performing these steps had to ;

j return to the same area repeatedly.

The licensee revised the procedure providing'the operators with more

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efficient directions. The inspector walked down this procedure simulating ;

the procedural steps and did not identify any unacceptable conditions.

This item is resolved. .

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(Closed) 83-26-04 (Unresolved Item) Emergency Lights

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The team reviewed the emergency lighting systems installed to assist plant

shutdown in the event of a fire and a concurrent loss of off-site power.

The emergency lighting is a requirement of 10 CFR 50 Appendix R l

Section III J. This requirement states that emergency lights with 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> :

I battery power supply shall be installed in all areas needed for operation '

j of safe shutdown equipment, and in access and egress routes thereto,

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The team observed that the licensee did not provide any such emergency

lights in the Control Room. The explanation given by the licensee was ;

that three different power sources are provided for the Control Room (CR) '

j lighting. These systems are the normal off-site power, and 'he emergency !

3 power from the emergency diesels which power the AC lighting system. The >

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station batteries also provide power to a DC lighting system in the '

control room.

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The team observed that all three power systems could be lost if a fire

occurred in the Cable Vault, since the cables from all three systems are i

routed through this area. The licensee reviewed this condition and >

installed emergency lights in the Control Room prior to the team leaving

the site.

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In addition, the team observed that the licensee did not provide emergency

lights in the torus catwalk area where personnel must be dispatched to

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perform shutdown actions. Also the emergency lighting in Fire Area RB-5

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was inadequate in that it was located too far from the panel to provide

adequate illumination. With regard to the lack of emergency lights in the

torus catwalk area the licensee relies on lights powered by the diesels.

However, this system was not reviewed for acceptance by NRC.

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The lack of emergency lights in the areas described above constitutes a

violation of 10 CFR 50 Appendix R Section III. J requirements (88-04-01).

The team observed that the area where the fire fighters assemble and dress

j did not have emergency lighting. The licensee stated that battery powered

emergency lights will be installed in the area.

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3.0 Purpose

This inspection was performed to ascertain that the licenseu is in

conformance with 10 CFR 50, Appendix R, Sections III. G, J, and L,

including exemptions approved by the Of fice of Nuclear Regulation (NRR).

4.0 Background

The licensee is required to comply with the requirements of 10 CFR 50

Appendin R, Sections III. G, J, and L. The schedule for compliance with

the above requirements is set forth in 10 CFR 50.48.

Section III. G of Appendix R requires that fire protection is provided to

ensure that one safe shutdown train remains available in the event of a

fire.Section III. J requires that emergency lights are installed in all

areas required for safe shutdown purposes and Section III. L specifies

the requirements for alternate shutdown capability.

The licensee, during an inspection conducted in August 1983, Report No.

83-26, was inspected to verify compliance with the above requirements.

This inspection identified several examples of violations of these

requirements. The violations were corrected as indicated in Section 2.0

of this report.

5.0 Correspor.dence l

Correspondence between the licensee and the NRC concerning compliance

with Section III. G, J, and L was reviewed by the inspection team in

preparation for the site visit. Attachment I to this report is a listing 1

of the correspondence reviewed.

6.0 Post-Fire Safe Shutdown Capability

6.1 Systems Required for Safe Shutdown

The licensee stated that the design basis fire is a fire without

off-site power availability. The safe shutdown systems for this

case are shown in Attachment 2. Reactor scram would be manually

initiated from the Control Room (CR). Vessel overpressurization is

prevented by self-actuation of the Safety Relief Valves (SRVs). !

Either Reactor Core Isolation Cooling System (RCIC) or High Pressure

Coolant Injection System (HPCI) may be used for high pressure coolant l

makeup. '

Wi t' 71 vision I power available, decay heat removal is accomplished

by HPCI, or the SRVs dumping steam to the suppression pool, with the

Residual Heat Removal (RHR) System in the Suppression Pool Cooling

(SPC) mode removing heat from the suppression pool.

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After depressurization, the Reactor Heat Removal .(RHR) System would i

be placed in Shutdown Cooling (SDC) mode. If both the SDC and i

Control Rod Drive (CRD) pumps are available, CRD pump flow is used l

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for low pressure coolant makeup. If the CRD system is unavailable, j

coolant inventory can be maintained by either one Low Pressure ,

Coolant Injection (LPCI) or core spray pump which would supply water :

to the reactor when the reactor low pressure permissive has been ,

satisfied. l

Fou- RHR pumps are available for LPCI injection with pumps A and B !

powered by Division II and pumps C and D powered by Division I, and

two completely independent core spray systems are available with ;

system A powered by Division II and system B by Division I.

If Division II power is available, high pressure makeup is provided l

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by the RCIC system. Vessel overpressure protection is identical to l

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the case with Division I power. Following depressurization, either R

RHR pump A or B in the LPCI mode or core spray A may be used to .

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Alternate safe shutdown for the Control Room, Cable Vault, Battery j

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Room, or Switchgear Rooms, is initiated from the Control Room by a ;

s manual scram of the control rods. In order to maintain reactor <

i coolant inventor /, the RCIC System will be used to provide makeup i

water. For hot shutdown, decay heat removal will be accomplished l

by the RN C and RHR Systems in conjunction with the safety relief l

3 valves. A number of other systems including HPCI, Core Spray, and L

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LPCI (in conjunction with ADS valve operation) can be used for !

} shutdown. For suppression pool cooling, the RHR System will be i

s used with the Service Water Systems to provide cooling. For cold ;

f shutdown, the RHR System will by used in the shutdown cooling mode. ;

The above systems will be monitored and controlled from the Control '

Room or RCIC control panel. The power sources for operations of the !

j above systems will be provided by the emergency diesel generators !

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and 125 V battery sources. !

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6.2 Alternate Safe Shutdown Areas

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, The licensee's safe shutdown analysis identified the need to provide ,

alternate safe shutdown capability in the Control and the Cable !

Spreading Room. !

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j 6.3 Remaining Plant Areas l

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j Safe Shutdown Plant Systems not in compliance with the requirements

j of Section III. G.2 of Appendix R must be provided with an alternate

j safe shutdown system unless an exemption request has been approved

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The licensee requested a number of exemptions to certain require-

ments of Appendix R which were evaluated and granted by the NRC.

Attachment 3 of this report is a listing of the areas where exemp-

tions were requested.

7.0 Inspection Methodoir;/

The inspection team examined the licensee's capabilities for separating

and protecting equipment, cabling and associated circuits necessary to

achieve and maintain hot and cold shutdown conditions. This inspection

sampled selected fire areas which the licensee had identified as being in

compliance with the Section III.G.

The following functional requirements were reviewed for achieving and

maintaining hot and cold shutdown:

Reactivity control

Pressure control

Reactor coolant makeup

Decay heat removal

Support systems

Process monitoring

The inspection team examined the licensee's capability to achieve and

maintain hot shutdown and the capability to bring the plant to cold

shutdown conditions in the event of a fire in various areas of the plant.

The examination included a review of drawings, safe shutdown procedures

and other documents. Drawings were reviewed to verify electrical

independence from the fire areas of concern. Procedures were reviewed

for general content and feasibility.

Also inspected were fire detection and suppression systems and the degree

of physical separation between redundant trains of Safe Shutdown Systems

(SSSs). The team review included an evaluation of the susceptibility of

the SSSs to damage from fire suppression activities or from the rupture

or inadvertent operation of fire suppression system.

The inspection team examined the licensee's fire protection features

provided to maintain one train of equipment needed for safe shutdown free

of fire damage. Included in the scope of this effort were fire area

boundaries (including walls, floors and ceilings), and fire protection of

openings such as fire doors, fire dampers, and penetration seals.

The inspection team also examined the licensee's compliance with

Section III.J, Emergency Lighting. The results of the inspection in this

area are discussed in Section 2.0 of this report. Appendix R,Section III.0,

Oil Collection System for the Reactor Coolant Pump, is not an Appendix R

requirement for plants, such as Vermont Yankee, since the containment is

inerted during normal operations.

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8.0 Inspection of Protection Provided for Safe Shutdown Systems

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8.1 Protection in Various Fire Area l

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! The team reviewed the protection provided to SS$s and work in !

progress in selected fire areas for compliance with Appendix R, !

Section III.G.1, 2 and 3. Particular attention was paid to the

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Reactor Building, RB, since this building contains th.. majority of .

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the Shutdown Systems. It was also in the RB that the majority of the l

Violations from the Appendix R requirements were identif_ied during l

1 the inspection described in Inspection Report 83-26. !

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The Reactor Building is a single structure. It consists of a single !

fire area separated into fire zones along an east-west line. The ,

zones are established based upon plant physical layout, as well as !

special separation inherent in the design. Fire zones on the north l

side primarily contain Division II equipment, while zones on the

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south side primarily contain Division I equipment. The principal i

safe shutdown systems associated with Division I include HPCI, Core

. Spray B, RHR C&D, RHR Service Water B&D, and Service Water B&D. The

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principal safe shutdown systems associated with Division II include l

RCIC, Core Spray A RHR, A&B, RHR Service Water A&C, and Service .

Water A&C. !

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j The established separation zones ensure that either the south side

(Division I power) or north side (Division II power) fire zones.are

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protected in the event of a fire in the opposite zone. The controls ,

and instrumentation necessary to support these systems also maintain

a divisional separation.

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j The review of the Reactor Building identified the following I

j concern:

The licensee identified several 20 foot combustible free zones

in support of exemption requests from the Appendix R require-

ments. These combustible free zones were described in a sub-

mittal to NRR to be areas where the cable trays traversing the

zone would be protected with a fire retardant. The fire ;

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4 retardant would be applied on either side of the combustible I

free zone in bands 5 to 7 feet long providing fire stops from

one fire zone to the other,

i The NRC issued a Safety Evaluation Report (SER) dated

i December 1, 1986 accepting the use of the fire retardant.

! However, the SER stated that this material should be applied

I over the entire 20 f t. zone, separating redundant components.

! It should not be limited to bands on the sides of the

! combustible free zones.

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The discrepancy was acknowledged by the licensee in an

internal document but was not brought to the attention of

NRC/NRR. The licensee, during the inspection, agreed to

provide the protection described in the SER as soon as plant

conditions permit. In addition, the licensee established fire

watches in the areas involved until the modifications are

completed. This is an unresolved item. (88-04-02)

8.2 Safe Shutdown Procedures Review

The team reviewed procedure number OP3126, Revision 3, dated

February 5,1988 titled "Shutdown using Alternate Shutdown

Methods",

i The scope of this review was to ascertain that the

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shutdown could be be attained in a safe and orderly manner,

to determine the level of difficulty involved in operating

equipment, and to verify that there was no dependence on

repairs for achieving hot shutdown. ,

The team did not identify any unacceptable conditions however,

the licensee agreed to address the following team observations:

1. Step No. 3 of the procedure lists immediate actions to be

taken by the operators prior to leaving the control room.

The included; Step 3B - run back recirculation pumps to

minimum Step 3C - manually scram the reactor, Step 30 -

close at least one MSIV per steamline, Step 3E - open

HPCI-24, and Step 3F place ADS bypass switch to

"Bypass".

The NRC noted that only one manual action is allowed prior

to axiting the control room. In subsequent discussions, it

was determined that all of these actions could be performed

outside the control room if necessary.

2. Appendix A "Alternate Shutdown Methods Flow Diagram" was

difficult to read because of its reduction from the

original. The licensee concurred and agreed to

investigate methods for making the diagran more legible. l

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3. Step numbers had not been assigned to instructions in ,

Appendix C for operating RHR in the "Torus Cooling Mode" l

or "Shutdown Cooling Mode." The licensee agreed to add ,

the step numbers to the procedure. l

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Procedure Walk-Through

The team walked through selected portions of procedure No. OP3126

to determine by simulation that shutdown from outside the control

room could be attained in an orderly and timely fashion. The

procedure walk-through was accomplished by four members of the

licensee's operations support staff.

The walkdown was initiated from the Control Room with the

following initial conditions:

Reactor at 100*. power with systems lined up in normal

I full power configuration.

Credit for one manual action prior to evacuating the

Control Room.

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Loss of offsite power.

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l * Manual start of the emergency diesel generators.

The team paid attention to the feasibility of each manual

action, ease of access, operator familiarity with the procedural

i steps, communication, emergency lighting, and the direction of

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the operators by the Shift Supervisor. The walkdown was halted

when the licensee had adequately demonstrated the capability to

achieve simulated hot shutdown conditions. The following items

were identified by the inspection team as concerns requiring

licensee's attention:

1. The inspection team observed that the operator performing

the procedure step to manually run back the recirculation i

pumps, encountered difficulty as a result of limited access

to the Bailey Positioners. The licensee committed to

review the concern and improve access to the Bailey

Positioners.

2. The licensee did not demonstrate that an adequate communi-

cation system exists to shutdown the plant. The primary

means of communication will be hand-held radios. The

Itcensee did not use these radios during the inspection l

because use of the radios in certain plant areas would risk l

tripping the reactor. The licensee committed to demonstrate

the adequacy of the radios when the plant is shutdown and i

inform the NRC resident inspector to witness the demonstra-

tion. The licensee will provide the NRC with the results of

these tests.

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The licen;ee did not nave a time-line analysis to verify

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that the procedure could be implemented with the minimum

man power available. The licensee committed to perform the

time-line check.

8.3 Protection for Associated Circuits

Appendix R,Section III.G requires that protection be provided for

associated circuits that could prevent operation or cause

maloperation of redundant trains of systems necessary for safe

shutdown. The circuits of concern are generally associated with

safe shutdown circuits in one of three ways:

Common bus concern

Spurious signals concern

Common enclosure concern

The associated circuits were evaluated by the team for common bus,

spurious signal, and common enclosure concerns. Power, control, and

instrumentation circuits were examined on a sampling basis for

potential problems.

The common bus associated circuit concern is found in circuits,

either safety related or non-safety related, where there is a common

power source with shutdown equipment and the power source is not

electrically protected from the circuit of concern.

The common bus concern is made up of two items:

Circuit Coordination

High Impendance Faults

8.3.1 Circuit Coordination

The licensee performed a coordination analyses of the 4160V Bus

No. 3, the 480 VAC system and all power sources required for

alternate shutdown.

The coordination analyses identified coordination deficiencias i

and included recommendations to correct non-coordinated condi-

tions. The team reviewed the analyses and maintenance records

to verify that the deficiencies identified by the analyses were

corrected.

The team did not identify any unacceptable conditions with

either the analyses or the corrective actions taken by the

licensee. The licensee performing circuit breaker and relay '

testing and maintenance at 18 and 36 month intervals.

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During the performance of the circuit coordination review the

team observed that for the 120VAC vital and instrument bus

circuits the licensee could not verify proper circuit coordina-

tion. In addition, the documentation presented for the time-current

characteristic curves of the 125 VOC circuits was inadequate in

that it was missing review and title blocks. The team noted

that these circuits are not required for alternate shutdown.

However, the licensee in the Safe Shutdown Capability Analysis

takes credit for the coordinated fault protection for all

distribution systems. The licensee acknowledged the coordina-

tion and documentation concerns raised by the team and committed

to finalize the analysis for the 120 VAC and 125 VDC circuits.

The licensee agreed to inform the NRC of any deficiencies

identified during the completion of this analysis.

This item is unresolved (88-04-03).

8.3.2 High Impedance Fault

The high impedance fault concern is found where multiple high

impedance faults exist as loads on a safe shutdown power supply

and could cause the loss of this supply prior to clearing the

faults.

The team did not complete the review of this concern because

the licensee's final analysis was not complete. A preliminary

review of potential high impedance fault concern was performed

by the licensee. This preliminary review indicated that this

issue was not a concern for VY. The licensee discussed with the

team, the scope of this analysis and committed to review all

power supplies of concern. They agreed to inform the NRC if any

deficiencies are identified as a result of this review. This l

item is unresolved. (88-04-04)

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8.3.3 Spurious signals Concern

The spurious signal concern is made up of 2 items:

False motor control and instrument indications can occur

such as those encountered during the 1975 Browns Ferry

fire. These could be caused by fire initiated grounds,

shorts or open circuits.

Spurious operation of safety related or non-safety related

components can occur that would adversely affect shutdown

capability (e.g. , R!iR/RCS isolation valves).

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The team examined, on a sampling basis, the following areas to

ascertain that no spurious signal concern exists:

High/ Low pressure interfaces

Current transformer secondaries

General fire instigated spurious signals

, 8.3.4 H_igh/ Low Pressure Interfaces

The teams review of the licensee's High/ Low Pressure Interface

l concern did not identify any unacceptable conditions.

8.3.5 Current Transformer Secondaries

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The licensee performed an analysis of the open secondary

circuit, current transformer (CT) concern. A discussion with

licensee representatives found the analysis to be based on

Vermont Yankee plant specifications which describe the physical

characteristics of control cabling connected to CT secondary

circuits. The analysis recognizes that if an open secondary '

circuit of CT were to occur, the secondary cabling may be

subjected to an overvoltage condition in excess of the cables

insulation rating. Such an overvoltage condition may result

in damage to the cable insulation. Because of the insulation

characteristics and "spiral wrap" construction of the cabling

used, the analysis concluded that if such an event occurred the

insulation damage to the cable would cause the CT to become

self shorting, reducing the CT secondary impedance and hence,

the secondary voltage, thus eliminating the concern.

The review of this analysis by the team did not identify any !

unacceptable conditions.

8.3.6 Fire Instigated Spurious Signals

The licensee provided isolation for fire induced

spurious signals by various methods including:

isolation / transfer control switches

rerouting of cables

a wrapping of cables with fire rated material j

administrative controls

A review of the methods listed above by the team did not

identify any unacceptable conditions.

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8.4 Common Enclosure

The common enclosure associated circuit concern may be found when

redundant circuits are routed together in a raceway or enclosure and

they are not provided with adequate electrical isolation protection, ;

or when a fire can destroy both circuits due to inadequate fire

protection methods.

At the time of the inspection, the licensee stated that:

Cables for redundant safe shutdown divisions are not routed

within a common enclosure.

Non-safety related cables that are routed together with cables

required to achieve post fire safe shutdown are protected by an

appropriate electrical isolation device.

Non-safety related cables which share a common enclosure with

cables required to achieve post fire shutdown are never routed

between divisions.

The review of this issue identified the following conditions that

need clarification. In the Reactor Building the team ot, served that

certain non-shutdown related number 12AWG conductors were protected

with 35 AMP fuses. 12AWG conductors are rated for 30 AMPS. The team

raised the concern that a fire may cause an overcurrent condition to

one of these conductors. Since these conductors are not provided

with the proper size fuse, a secondary fire could start elsewhere in

the building. These conductors may be routed to adjacent fire areas.

This would compromise safe shutdown capability. The team did not

l identify any cases where this situation exists. However, the

licensee could not provide assurance that this condition was analyzed

and found acceptable. The licensee agreed to review this concern and

inform the NRC if any deficiencies were identified. This item is

)! unresolved. (8S-04-05)

8.5 Fire Brigade _ Training

'

The licensee requested several exemptions from Appendix R

requirements. These exemptions were granted partly on the belief

4

that the fire brigade will respond promptly and extinguish any fires.

For this reason the team reviewed the licensee's Fire Brigade i

training and readiness to respond.

The team reviewed training and drill records and also observed a

drill conducted at the request of the team.

No unacceptable conditions were identified.

l

.__ _ _ _ _ _ _ _

.

\

.

15

9.0 Unresolved Items

Unresolved items are matters for which more information is required in

order to ascertain whether they are acceptable, violations, or

deviations. Unresulved items are discussed in Sections 8.1, 8.3 and

8.4

10.0 Exit Interview

The inspection team met with the licensee representatives, denoted in

'

Section 1.0, at the conclusion of the inspection on February 11, 1988,

and the team leader summarized the scope and findings of the inspection

at that time.

The team leader also confirmed with the licensee that the report will not

contain any proprietary information. The licensee agreed that the

inspection report may be placed in the Public Document Room without prior

licensee review for proprietary information (10 CFR 2.790).

At no time during this inspection was written material provided to the

licensee by the team.

>

- t

__ . _ _ _ _ _ .

_ _ - - _ _ _ - - _

'

.

ATTACHMENT 1

LIST OF CORRESPONDENCE

FVY 85-38, dated April 24, 1985, requesting exemptions from the provisions of

Appendix R.

FVY 85-60, dated June 28, 1985, providing Vermont Yankee's evaluation relative

to IE Information Notice No. 85-09.

VYL 85-47, dated July 26, 1985, providing additional information regarding

Appendix R exemption requests.

(No Number), dated August 2, 1985, providing additional information regarding

Appendix R exemption requests.

FVY 85-73, dated August 16, 1983, providing additional information regarding

Appendix R exemption requests.

FVY 85-102, dated 0: tober 31,1985, requesting exemption from the provisions.

of Appendix R.

FVY 86 -56, dated June 10, 1986, request for exemption special circumstances

and clarification.

NVY 86-240, dated December 1, 1986, NRC letter to licensee, granting

exemptions.

FFY 86-74, dated August 15, 1986, request for Appendix R exemption.

,

L __) - t_ C ass m M

VERMONT YANKEE NUCL O O AT M E Eggg

VERMONT YANKEE NU. .AR POWER STATION

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SAFE SHUTDOWN SEQUENCE FOR APPENDIX R SECTION IILG EVALUATION- ..

'~.**~~ VERMONT YANKEE NUCLEAR POWER PLANT -

OFFSITE POWER NOT AVAILABLE

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ATTACHMENT 2

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___

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

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ATTACHMENT 3 '

EXEMPTION REQUEST AREAS AND DESCRIPTION i

!

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Area or Zone (s) Exemption Request

j

i

.1. Area RCIC - RCIC pump / Turbine Room Separation barrier !

2. RB-1/RB-2, Reactor Building Torus Area Suppression !

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3. RB-1/RB-2, Reactor Building, Northeast Suppression

and Southeast Corner Rooms ;

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4 RB-3/RB-4, Reactor Building, Elevation Separation and Suppression

252', Northeast Corner. Vital MCCs >

'

1 5. RB-3/RB-4, Reactor Building, Elevation Separation

l 252', Northwest Corner !

4 '

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{ 6. RB-5/RB-6, Reactor Building, Elevation Suppression

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280', East Side, Instrument Rscks f

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