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Insp Rept 50-029/90-17 on 900730-0803.No Violations Noted. Major Areas Inspected:Audit of Licensee Action in Response to Recommendation Described in Generic Ltr 88-17
	ML20058D365
Person / Time
Site:	Yankee Rowe
Issue date:	09/14/1990
From:	Chiramal M, Lopez A, Lyon W; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:	;
Shared Package
ML20058D356	List: ML20058D350; ML20058D365;
References
	50-029-90-17, GL-88-17, NUDOCS 9011060072
	Download: ML20058D365 (15)
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V. S.-NUCLEAR REGULATORY COMMISSION

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REGION I

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, Report No.

90-17

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Docket No.50-029

License No.

OPR-3

-Licensee:-Yankee- Atomic Electric Company

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580 Main Street

Bolton, Massachusetts 01740-1398

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Facility Name: Yankee Rowe Plant

.: Inspection At: Rowe, Massachusetts

Inspection Conducted:: July 30 - August 3,1990

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Inspectors:

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A. E. Lopez,-Reactor Engineer, Special

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LTest Programs!Section, EB, DRS

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>WC C . . Lyon , S r . Rreactor ' Engineer

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Reactor Systems Branch,.OST,,NRR

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JApprovedjby:--

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'M. Chirama',--Acting Chief, Special

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LTest ProgramsLSection,.EB, DRS

= Inspection = Summary:

Routine unannounced safety. inspection:on Julyf30_ 2

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- August 3,.1990 (Inspection Report No.. 50-029/9.0-17)

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1 Areas Inspected:- Audit ofclicensee actions in response to the

-recommendations described -in Generic Letter _ (GL) 88-17:" Loss ofl Decay: Heat--

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- Removal, for operation'of' the plant.during shutdown.

The inspection

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reviewed training, containment closure, instrumentation, procedures, plant

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' hardware, -and plantistaf f awareness .as' related to reduced reactor coolant

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' system (RCS)1 inventory operation, operation leadi.ng to a reduced inventory

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icondition', andsgenera1Loperation of the shutdown cooling-(SOC) systemiaiso

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iknown as=the residual heat 1 removal system.

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Results: The GL 88-17 recommendations were not fully implemented. Two items

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remain outstanding: (1) Level instrumentat'

was not in place. This item will

remain unresolved (Unresolved item 50-029/90-17-01) pending the review of the

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complettd installation,

(2) Procedures are needed to include the inspection

observations identified in this report.

This item will remain unresolved

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(Unresolved item 50-029/90-17-02) pending the rewrite and review of the

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procedures for shutdown operation.

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-The combination of licensee preparation and completed actions supports a

conclusion that there are no violations and no immediate safety concerns

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regarding the GL 88-17 recommendations.

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DETAILS

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1.01 Persons Contacted

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1.1 Yankee Atomic Electric Company

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M. Desilets, Acting Operations Training Supervisor

S. Fournier, Principal Engineer

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K. Heider, Reactor Engineer

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T. Henderson, Acting Plant Superintendent

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D. King, Maintenance Support Supervisor

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T. Smith, Maintenance and Technical Training Supervisor

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N. St.Laurent, Acting Opations Manager-

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D. White,-Training

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F. Williams, Operations Support Supervisor

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1.2' O.S Nuclear Regulatory Commission

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T. Koshy, RSr. Resident Inspector

M. Markley, Resident Inspector

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- *; Denotes presence at exit meeting held on August 3,-1990.

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2.0 Review of Licensee Action in Response to GL 88-17, Loss of Decay Heat

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Removal-(tis 2515/101 and 2515/103)

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/Lossof-shutdown. cooling =(SDC)and'the~ consequences'ofsucha-lossareof,

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increasing._ concern toLthe NRC.

Many such events have occurred during reactor'

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coolant system:(RCS) drainingf and during operation in a reduced inventory or

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mid loop condition.

( AL reduced RCS inventory condition exists when the RCS -

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water leveliis-lower than a nominal three feet below.the reactor! vessel (RV)f

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' flange. A mid-loop condition l exists when the actual water Lleve111silower: than-

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L the hot : leg flow area at the. junction of = the hot -leg with the.RV.)' These

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conditions:of ten ' occur when the RCS and containment are bothlopen 'so that only

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one barr.ier, exists to-prevent release of fission products to the? environment.

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a4 loss of core cooling:(significant enre uncovery) under these' conditions could

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lead-to a release to the' environment;

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GL 87-12, " Loss of Residu'al Heat Removal'(RHR) while the Reactor-Coolant-

. System (RCS)-is partially filled" was issued-to all licensees of operating 1

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PWRs'and holders of' construction permits 1on-July 9,11987! This1GL identified --

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.many of.the problems and requested information related to' shutdown operation.

Licensee responses clearly indicated a_ lack of understanding offshutdown -

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operation, _particularly during a mid-loop condition;

Preventable events-

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continued-to occur.

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The seriousness-and continuation of this problem resulted in issuance of

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" Loss of Decay Heat Removal (Generic Letter No. 88-17),10 CFR 50.54( f)." -

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In addition, the Director.of NRR wrote to the chief executive officer of each

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licensee ~ operating a PWR in which he stated "We consider this issue to be of

~high priority and request.that you assure that your organization addresses

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it accordingly." He also wrote to each licensed operator at all PWR plants-

on " Operator Diligence while in Shutdown Conditions" and enclosed a copy of

GL-88-17.

GL 88-17 required the licensees of operating nuclear plants to respond with

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their plans regarding two sets of recommendations

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A short-term program entitled " Expeditious Actions," and

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A long-term program entitled " Programmed Enhancements."

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~This inspection audited licensee actions regarding both sets of

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The: intent of GL 88-17 was to address all aspects of operations under reduced

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.inventoryLconditions, including prevention of an unidentified or unplanned

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- entry;into such-a condition as= well as planned entry. .Thus, both reduced and

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non-reduced inventory operation are addressed ,

Containment closure operations

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.are addressed.in!both. expeditious actions.and programmed enhancements.

2.1;' Yankee Rowe Operation During Shutdown

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TYankee Rowe has.not . operated in a-mid-loop condition. No maintenance

. operations are-conducted.during mid-loop operation, nor 1s mid-loop operation

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feasibl.e: since analyses have shown that vortexing occurs when.the water level

is one inch below.the top of; the hot leg. Operation with water level at the.

top of,the: hot leg,is permitted -via procedures, but-is both unnecessary and -

imprudent.: The licensee hasJagreed to' change these procedures,- and will

specify an actual minimum water, level.

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Yankee: Rowe has seldom been operated at reduced inventory since it began =

" operation:in'1961.

The only requirement for,such operation.is:for

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imai.ntenance:on,a loo'p stop valve and a few other unisolable-components.

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Lother valves-are maintained with a. higher water. level. -(One exception is the-

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-valve'in'the SDC system' suction pipe closest'to:the-hot leg. ' Opening the RCS

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3 pressure. boundary at this' valve would require removing fuel fromithe RV.)

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lRVl head removal and installation.is accomplished!with the water level.. roughly;

-six inches below the RV f.lange.

Steam generator .(SG) tube ' draining is accomplished by. closing < the loop stop -

valves. Draining SG tubes;while-in mid-loop is eliminated, a decided

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advantage and'SG nozzle dams are not.used,

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The licensee requires at least three additional operators for monitoring

performance of the SDC system when going into a reduced level operation while

draining below the RV flange and for partially filled operation (procedure

OP-2162). Partially filled operation is undefined.

It was described to us

- as the equivalent of a reduced inventory operation.

These operators are

assigned as follows:

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One operator to monitor shutdown cooling and SDC pump operation at the

SDC pump location,

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One or more operators in containment to monitor and verify operation of

the tygon tube level indicators

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One operator in the control room (CR) to monitor SDC parameters

A further requirement is that RCS temperature must be reduced to below 100 F

before water level can be taken lower than a few inches below the RV flange

(Procedure OP-2162 Rev 22 Att E page 5).

This is a prudent operational step

since time to core uncovery is shorter at Yankee Rowe than at most plants,

with a hot leg opening (27 minutes vs 1 to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months ).

The' licensee also operates the plant with the containment equipment hatch in

place most of the time and other containment openings are minimized. The

equipment hatch is rarely removed during reduced inventory operation, but is

permitted by OP-2162, Att. E, precautions.

2.2 Training - expeditious action 1

The inspectors-verified that training conducted by the licensee made the

-licensee personnel aware of the risks associated with operation in a reduced

inventory condition.

However, an up-to-date_ synopsis of loss of SDC events

and applicable lessons learned was not incorporated in the lesson plans.

Also, similar training was lacking for other personnel who could influence

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reduced-inventory operation, such as those involved in maintenance and outage

planning.

Conclusion:

Training, is adequate; however, additional measures to improve its

operator and non-operator training during a reduced inventory condition are

being taken.

2.3 Containment Closure - expeditious action 2

Yankee Rowe's Procedure OP-2162, " Operation of the. Shutdown Cooling System,"

Attachment E states in precaution No. 12 that the equipment' hatch cover can

be removed if there are no spenings in the main coolant system (excluding

vents) as long as it can be re-installed and secured with four bolts 30

minutes before core uncovery occurs if shutdown cooling is lost.

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criterion is more conservative than the GL 88-17 criterion of closure prior

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toLcore uncovery.- However, the-licensee had not fully considered all of the

conditions inside containment following initiation of boiling, in determining

the ability to close-containment.

The inspectors also found that no accurate

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' determination of time to close penetrations had been made nor was it apparent

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that the licensee had considered potential manpower requirements if multiple

penetrations existed. Also, the procedures did not provide steps to reasonably.

assure that containment openings were tracked.

This topic is discussed further

in Section 2.5.

In OP-2162, Attachment E, step 8f, states that the equipment cover should be

assured in place, secured by four bolts such that no visible gaps are

present. The licensee repre:entatives stated that the no gaps criterion was.

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established by visuai voservation of the space between the flanges once the

hatch cover was it -lace.

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Conclusion:

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The licensee agreed to consider a containment closure criterion of

closure prior ~ to initiation of boiling if there are openings in the RCS-

_presture boundary'that could allo'w significant quantities of steam to

escape'into containment.

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The licensee;will. perform a timed walk-through of containment penetration

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, closure operations to provide an accurate determination of the time it

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takes to close those penetrations.

Incorporation of'the results of such

-walk-throughs into appropriate procedures is necessary to meet the closure -

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recommendation of'GL 88-17,

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.Thefinspectors determined that vi ual observation to assure the no gaps

criterion for?the equipment hatch closure, satisfied the recommendation

of:GL 88-17,

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Instr'umentation - expeditious actions.3 and 4'

programmed enhancement 1

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2.-4' 1:. Core exit temperature. 1GL 88-17 recommended at least two RCS

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. temperature indications;in the control room (CR) that are representative-of

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core exit temperature whenever the head.is on the RV.

Visible and audible

indications of abnormal conditions were recommended.

4The licensee has provided for temperature indication in the CR during shutdown

"oper.ation1when -the jhead ..is on the RV except for the time when head removal and

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installation operations-are in progress.

Thislco'uld be-for a shift or as long'

asisoveral? days.' This is inconsistent with the GL 88-17; recommendations.

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iAlthough, a'n alarm on high~ core exit temperature was not referenced in:the

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material that was audited,- such an alarm is provided and that it will' be-

appropriately set and-referenced in procedures. _This is necessary to meet the

GL recommendations.

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Conclusion: The licensee agreed to consider use of temporary connections to

provide core exit temperature indication in the CR except for times that are

very close to actual head movement.

Long times of unavailability are incon-

sistent with the intent of GL 68-17.

Suitable compensatory measures maybe

needed, for long times of unavailability.

Licensees should also consider

immrdiate connection of core exit thermocouples if a loss of SDC occurs with

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thr RV head on the vessel while core exit thermocouples are disconnected.

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2,4.2 Reactor coolant system wster level.

Two independent RCS

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water level indications in the CR were recommended in GL 88-17.

Visible and

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audible indications of abnurma' conditions are recommended in the GL.

Yankee Rowe uses two tygon tubes inside containment and will have two

transmitters for indication in the CR. Work to install the second

transmitter was under way during the last day of the inspection.

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display of the tygon tube indication has been used occasionally to reduce

observer dose rate, with the CRT still located in containment.

CRT location

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in the CR has not been accomplished,

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The tygon tubes are close together and connected to a permanently installed

vertical board provided with level markings.

Level transits

were used to locate these markings during installation.

The inspectors

observed that this was a professionally installed system.

The board and

control valves are located in a relatively high radiation area.

Yankee Rowe RCS level indications are as follows:

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" Wide-range" tygon tube and transmitter - The tygon tube is connected

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roughly at the top of the hot leg (high pressure end) of the RCS with the

reference (low pressure) end open to containment near the top of the

pressurizer.

It is capable of indication over the range from the top of

the pressurizer to about the top of the hot leg.

There is a potential for

air introduction into the water (hot leg) side due to an elevated section.

Lowering water below the level cf the hot leg connection would introduce

air and lead to erroneous indication. This error would continue even if

the level was subsequently increased.

This characteristic was not

identified in the procedures however, it will be identified in updated

procedures.

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Referenctng to the containment atmosphere can introduce error in the

level indication-

This is addressed in OP-2162 Rev 22 Att E step 23

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with the statement, " Vacuum under the head should not exceed 1 inch

water pressure." Such a vacuum would cause the level indication to be

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lower than is actually the case, a controlled conservatism.

The wide range level. transmitter, indicates in the CR on the basis of

pressure difference between the bottom of the hot leg and the top of

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the pressurizer.

The licensee estimates the accuracy to be within 5

inches; sufficient for the upper range of reduced inventory operation but

insufficiently accurate for control in the vicinity of mid-loop A low

level alarm capability is provided,

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" Narrow-range" tygon tube and transmitter - The tygon tube is connected

to a manifold that allows sampling several locations representative of

the bottom of the RCS hot leg. The reference end will be open to the

containment atmosphere at the elevation of the top of the pressurizer.

The transmitter has CR indication, uses the narrow range tygon tube high

pressure connection and is referenced to the top of the RV head.

Indication is provided from the bottom of the hot leg to about 42 inches

above the bottom of the hot leg. A low level alarm capability is

provided.

The licensee anticipates accuracy to be within one inch.

An inverted "U" configuration was observed in the narrow-range tygon

tubing that was being assembled which could potentially trap air and

introduce a level indication error.

The licensee changed this to

provide a continuous tubing slope and eliminate the potential problem.

The inspectors did not evaluate the RV head tubing since it was not

installed.

This item will remain unresolved pending the review of the

completed installation.

(Unresolved item 50-029/90-17-01)

'Tne two narrow-range level indications are dependent since they use a common

high pressure connection.

The narrow range level transmitter is not used

until level is close to on-scale to prevent over-ranging the pressure

transducer.

Hence, only one level indication is available in the CR until

level is about two feet above mid-loop.

A second indicatior, is provided via

the wide-range tygon tube.

The connection between the narrow range level transmitter and the-RV head

must be broken for head removal and will not exist until head reinstallation.

Narrow range indication is not necessary for head movement operations since

water level is no lower than a nominal six inches below the RV flange.

Conclusion: _ The wide-range pressure transmitter and wide-range tygon tube

provide level indication, with suitable accuracy, until actual water level

has been reduced to roughly a foot above the top of the hot leg,

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narrow-range pressure transmitter and narrow-range tygon tube-cover mid-loop

and close to mid-loop operation, with the previously identified dependency.

However, Yankee Rowe never intends to operate in mid-loop and the procedures

are to be rewritten to reflect this situation, as is discussed below. We

find the licensee has provided reasonable coverage of level indication and

has met the intent of GL 88-17 with the. exception of the level installation

unresolved item discussed above.

We understand level alarm settings will be determined and included in the

procedures:during the procedures rewrite (see section 2.5).

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2.4'3 ~ Shutdown Cooling (SDC) system monitoring.

The capability-to continuously

monitor SDC system performance from the CR is recommended in GL 88-17 whenever

a SDC system is being used for cooling the RCS.

Visible and audible indications

'of abnormal conditions are also needed.

The Yankee Rowe SDC system consists of a typical RHR train including a pump,

a -Component Cooling Water (CCW) heat exchanger, and a backup train identified

asithe low pressure surge tank-(LPST) system.

The LPST has an identical pump

and'the other components and layouts are similar.

SDC and LPST system flow

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rates are provided in the CR, as is SDC pump motor current.

LPST pump motor

current is not displayed in the CR. The SDC system is started and operated

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No SDC system alarms are provided, an inconsistency with the GL 88-17

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recommendations.

However, the licensee only rarely enters reduced inventory

operation and, as discussed above, provides three additional operators to.

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continually' observe SDC and LPST system performance at the pumps, to observe

displayed parameters in the-CR, and to observe level indication on the tygon

tubesLin the containment.

Conclusion:

The continuous operator coverage of the.SDC and LPST systems,

the rarity of entering reduced inventory = operation, and the avoidance of

entering mid-loop operation are sufficient to compensate for the lack of

Lalarms.

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2.5 Procedures -: programmed enhancement 2

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GL 88-17 recommended procedures and controls to-cover both normal and -off-

fnormal operation during- reduced inventory-operation and -that provided -a basis

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for entry into a reduced -inventory . condition,.

These.were to cover operation-

Lof the NSSS, the containment,-and supportingEsystems under conditions for

which cooling would normally- be provided by SDC: systems.-

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The: licensee was planning to rewrite shutdown-operation = procedures prior to

this inspection.: LThis was;to include coverage ~ of the new instrumentation _

and: numerous other improvements,' including a possible format change.

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rewrite was' postponed when thel decision was made not.to enter. reduced

inventory during the outage, and willLbe accomplished later. Therefore,

.no attempt 1was made'to identify all" items related to the new instrumentation

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in this inspection. report,

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Several; general = observations were noted that are: identified'here'and will

nottbe addressed further.

These include:

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1There is 'a tendency. to use technical specifications (TSs) in preparing'

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hutdown' operation = procedures. This is often-inappropriate. .TSs

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generally were developed-for power operation and;somewhat for refueling.

They-are:asLa rule inappropriate for coverage of operation during

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shutdown.-

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The= term " drained down operation" is not defined. We were told this

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means a level lower than a few inches below the RV flange.

" Normal

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operating _ level" is also undefined.

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Several procedures discuss and allow operation-in or close to mid-loop.

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is'not'a necessary condition at Yankee Rowe and the procedures should reflect

actual lneeds. The licensee acknowledged the observation.

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.A number of_ procedures and related reports were audited as part of this

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-inspection.. Inspector comments and licensee agreements where appropriate

are-provided below.

In general, once an observation is made it is not

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repeated _even if the same commen_t applies in numerous locations and -

procedures.

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2.5 1 AP-7309-Rev Original, " Calculation of MCS Heat-up During Loss of

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Shutdown Cooling Event, November 1988,

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See Section 2.5.3.

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2.5.2' OP-2119<Rev 10;-" Preparation for-Maintenance and/or Inspection and

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Return to Service of Unisolatable Main Coolant System Components,"; November 1988.~

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Conditions.inside containment if RCS boiling occurs are not adequately

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considered.

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OP-2162 Rev 22,= " Operation of'the Shutdown Cooling' System," February 1990.

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.Att E:page 2' .Two temperature indicating devices-are referenced. Only the

core exitJthermocouples are suitable,

f Att E; page 2L-- 0P-3122 is the wrong procedure - Thi s . should be- 0P-3121.

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Att E- page_6 step--20 - The blank- flanges were described as designed for.

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greater than.100 psid ,and are constructed of carbon steel.

Calculated lRCS:

. pressure:with one code valve: removed for-the limiting case is 80 psia. - This

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~1ncludes:a water 1.nventory-in the_ pressurizer.

This is'an acceptable

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cAtt'E page.10 step'5 --The tank level indications are to b'e: logged once per_'

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hour.while in~a drained ~down condition. They should-be' monitored closely

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.during' draining.and compared.to expected. levels based upon RCS_le w s-

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Jindication'as"a cross-check ontolant control.

TheLlicensee agreed to'make

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this: change.

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1 Space is provide'd for writing a. procedure for-decreasing and increasing RCS-

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-level, but no. procedure is provided.

The licensee. stated these are usually

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one' time evolutions, are rarely'done, and may be-done differently each time.

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2.5.5 OP-4239 Rev 10. " Verification of Containment (VC) Integrity and

Operability Check of the VC and Spent Fuel Pit (SFP) Ventilation Systems,"

December 1988

This procedure is used to track containment openings and is presently is

limited to refueling.

The licensee has agreed to change it to be applicable

to shutdown operation. Other procedures will similarly be changed to be

consistent with this redefinition of coverage in OP-4239.

2.5.6 OP-3254 Rev 14, " Total loss of AC with Shutdown Cooling in service,"

June 1990.

This title is misleading since coverage is limited to a partial loss of AC

power.

A total loss of all plant AC power is not addressed.

Discussion - The 27 minutes to core uncovery example should be added to

provide perspective to the potential seriousness of this condition.

Page 9 item 20 "If shutdown cooling cannot be re-established, then review

OPF-4239.1 and close all containment penetrations providing direct access to

outside atmosphere within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months [TS 3.9.8.1]" is inconsistent with GL 88-17

and is not acceptable for many of the conditions that may exist.

The following procedures were reviewed with no iurther comments found:

- OP-2162 Rev 18, " Operation of the Shutdown Cooling System,"

November 1988.

- OP-3117 Rev 16, " Refueling Accidents," June 1990.

- OP-3121 Rev .1, " Loss of Shutdown Cooling During Drained Down Operation,"

December 1988.

2.5.7 Additional licensee documentation reviewed for this inspection and

inspector comments included:

Drawbridge, B. , " Response to Expeditious Actions of Generic Letter 88-17,"

Letter to NRC from Vice President and Manager of Operations, Yankee Atomic

Electric Company, January 3, 1989.

See Drawbridge, 2/1//89.

Papanic, G. Jr., " Additional Information for Proposed Change 227," Letter to

NRC from Senior Project Engineer, Yankee Atomic Electric Company, BYR 90-87,

June 27, 1990.

No comments.

Schultz, S. P. , " Proposed Technical Specification Change to In::orporate 'USNRC

Generic Letter 88-17 into Yankee's Technical Specifications," letter to NRC

with Synopsis and Attachments from Vice President, Yankee Atomic Electric-

Company, PC 227, April 20,-1990.

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Page 1-6 --Reduced level operation is defined as a RV water level lower than

'

2 feet below the RV flange with irradiated fuel in the reactor.

This is an

acceptable definition since it is more conservative than the definition

provideu in GL 88-17.

However the licensee's procedures are not always

'

consistent with this 2 foot definition.

See, for example, OP-2119 Rev 10

item 13, which references a three foot elevation. The usage of " drained

down" in many procedures is also inconsistent with this definition.

Drained.

down was described as' a few inches below the RV flange and was assigned

essentially the same meaning as reduced inventory insofar as many procedures

'

were' concerned.

Fintily, this 2 foot definition was not found in any of the'

procedures audits.

The licensee will provide a consistent usage in the

j

procedure-after the TS change has been approved.

" Reduced Inventory Operation and E0P Instrument Changes," Engineering Design

-

Change Request, Engineering /QAD Review Forms, Enclosures, and References, 89-

305,. March 5, 1990..

'

No comments.

!

0rawbridge, B. " Response to. Programmed Enhancements of Generic Letter 88-17,"

letter from Yankee Atomic Electric Company to NRC, BYR 89-030, February 10,

c1989.-

No comments.

' Conclusion: -The licensee-has agreed to expand the rewrite to. include

Linspection-observations identifted in this report'.

The. licensee-has also

,

Agreed to complete this _ work prior = to the next reduced-inventory operation

,orKprior-to the next planned refueling _ outage-(presently _ February 1992),,

whichever occurs 'f_irst. --This item will rema,in unresolved pending the rewrite

and review of 'th~e procedures for shutdown operations.

(Unresolved Item 50-

"

029/90-17-02)'

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2;6 : Analyses - programmed enhancement 4

!

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~ Analyses were recommended'to provide a basis for procedures, instrumentation

installation-and response, and' equipment /NSSS interactions and response. A

complete understanding of NSSS behavior under shutdown operation was

indicated to be the: objective.

rYankee_Rowe personnel are clearly familiar with-the Westinghouse,0wners Group

. analyses previously= reviewed by NRC (WCAP 11916).

Additionalianalyses have

beenLperformed-for Yankee'Rowe. The. licensee'has made reasonable use_of such

r

material inspreparing<for operation within the scope of GL 88-17 and we have'

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' covered several2 areas where there.were-questions in above sections of our

-inspection - report. ' Analyses were not audited during this inspection.

4

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13

2.7 RCS Perturbations - expeditious action 5

programmed enhancement 6

The recommendation was for procedures and controls to avoid perturbations

while-in a reduced inventory condition.

This is particularly important

during the first four weeks follawing shutdown when decay heat removal rates

are high.

One espect of this recommendation was addressed in identified training

weaknesses. Other aspects have been addressed in the procedures that were

audited.

RCS perturbations are considered to have been addressed on a

limited audit basis.

Conclusion:

This topic should be re-examined following rewrite of procedures

and modification of training.

2.8 Equipment and RCS Inventory Control - expeditious action 6

programmmed enhancement 3

GL 88-17 recommended assurance that adequate equipment of high reliability

was provided for cooling the RCS and for avoiding a loss of RCS cooling. At

Two means of adding inventory to the RCS that are in addition to normal SDC

systems were to be provided. One should be a high pressure safety injection

pump or an equally ef fective and reliable means of injecting water. Water

addition rate should be sufficient to keep the core covered while taking into

account water losses due to the RCS configuration and the water injection

location.

The inspectors verified that in OP-2162, Att. E, prerequisites 13 and 14,

the licensee provides- a minimum of two charg.ing pumps (two are needed to

obtain adequate flow) and a purification pump, all with operable flow paths,

and a minimum of two SGs.

Safety injection pump capability is to be added

following NRC approval of TS changes.

Conclusion: The procedures and administrative controls established were

found to be consistent with the requirements described in GL 88-17.

2.9 Hot Leg Flow Paths - expeditious action 7

_

Yankee Rowe does not. use SG nozzle dams and this item is not applicable.

2.10 Loop Stop Valve Operation - expeditious action 8

GL 88-17 recommended procedures and controls to reasonably assure that all

hot legs are not blocked simultaneously by closed stop valves unless

suf ficient venting was provided to prevent pressurization of the RV upper

plenum or unless the RCS configuration prevents RV water loss if

pressurization should occur.

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-..:

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['

14

The licensee requires in procedure OP-2162, Att. E.,

prerequisite 14, that

-the water level in'two steam generators (SGs) be greater than 22 ft and the

associated hot:and cold leg isolation _ valves be open.

Yankee Rowe is presently not operated in a reduced -inventory condition with

cold leg openings since safety injection pumps are not available.

This-

)

condition is anticipated to change before the next reduced inventory-

operation because a technical specification change has been requested,

i

Conclusioni The inspectors concluded that-the licensee's controls of the

l

E

loop stop valves.during-reduced inventory operation are consistent with the

'

_ requirements discussed in GL 88-17,

2,11 Technical-Specifications - programmed enhancement 5

Technical specifications:that' restrict or limit the safety benefit of the

actions-identified in GL-88-17 should have been identified and appropriate

changes submitted to NRC for approval.

Such changes have been_' submitted. They were not reviewed during this

inspection.

1

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L3.0 Summary /Conslusions

The. inspectors found that all-of the GL recommendations were not fully implemented,

i

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- however, actions were sufficient to' meet most 'of the intent of the GL.

-

3

I

The licensee decided not to enter reduced.f nventory during.this outage

i

.

L

^,therefore,,the._ inspectors could not get a: first hand appreciation of the:

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n

activitiesgand; management involvement in this condition.

However, the

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P

inspectors'found the licensee t'o be knowledgable a'nd responsive to the

~

concerns discussed in.GL 88-17 and to the findings discussed in this report,

y

i

4.0-Exit Intervi n

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~

^\\

.

On / August 3,1990, an exit interview was conducted Lwith the Licensee's' site.

1 representatives (denoted inL Sqction 1) to summarize the observations and

_i

A

-conclusions of this inspectio1. 'At/no time during this inspection was

!

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written material'providedito-the. licensee by: the inspector. LBased on the

ENRC Region;I: review of this. report and the'discussionsLheld with licensee _

j

representatives-during this inspection, it was determined that this report'

w

1

.

idoes;not'.contain information subject to'10-CFR 2.790 restrictions,

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"

El G IOJJ I OPEN ITEM INFUT l'oKM

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(FORM 6)

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Choc); i f changed

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cinco Ixit Meeting

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40' l 7

Input Deto

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A. Add New Items:

Originator:

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Remarks

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B.

Modify > Update:

Resp.

Item No.

Type

.Sec

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C.-clo2e:

Closing

closing

. Item No..

Remarks

Item No.

Remarks

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TSS 1/90

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ML20058D365

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