IR 05000293/1988032

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Insp Rept 50-293/88-32 on 880912-16.Violations Noted.Major Areas Inspected:Corrective Actions That Resulted from IE Bulletin 85-003 That Addressed Improper Limit Switch & Torque Switch Settings in motor-operated Valves
ML20204D708
Person / Time
Site: Pilgrim
Issue date: 10/13/1988
From: Anderson C, Thomas Koshy, Julio Lara
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20204D688 List:
References
50-293-88-32, IEB-85-003, IEB-85-3, NUDOCS 8810210204
Download: ML20204D708 (24)
v • d • e


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U.S. NV; LEAR REGULATORY COMMISSION

REGION I

Report N /88-32 Docket N License N DPR-35 Licensee: Boston Edison Company

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RF6T1 Rocky HilTKoud Mymouth, Massachusetts 02360 Facility Name: Pilgrim Nuclear Powar St! tion Inspection At: Braintree and Plymouth, Massachusetts _

Inspection Conducted: September 12-16, 1988 Inspectors: .5ja b Thal /

T.' Koshy, Senior Rea'ctor Engineer

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date iV clQ kr T bcla fof/)ffy J.' La , Reactor Engineer date Approved by: O .A .

_ /o!/3 i C7J. Anderson, Chief, Plant Systems date Section Inspection Sumar +: Inspection on Septerrber 12-16, 1988 (Inspection Report

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Areas Inspected: ~

Special announced inspection to review the corrective actions tha: resulted from IE Bulletin 85-03 that addressed improper limit switch and torque switch settings in motor operated valves. This inspection reviewed the engineering and maintenance activities to assure the operational readiness of the motor operated valves. This inspection also looked at six previous NRC finding Results: The lic m see has addressed all the significant aspects of tne ETTetin. The engineering organization did not specify the special maintenance requirements for rnaintaining the torque and limit switche The engineering organization was not knowledgeable of certain of the plant maintenance activities that ir. fluence design bases, Two violations were identified based on previous findings (see Section 5.1 and 5.2). Licensee corrective actionc for previous findings were thorough and complete, es10210204 es?o14 PDR ADOCKOS00p]3

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DETAILS 1.0 Persons Contacted 1.1 boston Edison Company (BEco)

R. Anderson, Plant Manager S. L. Bibo, QA Audit Division Manager P. T. Cafarella, Sr. Mechanical Engineer J. Coughlin, Principal Electrical Engineer

  • N. Desmond, QC Division Manager R. V. Fairbank, NED Design Section Manager
  • F. N. Famulari QA Manager H. D. Goettsch, Material Management Manager
  • P. Hamtiton, Comp'tance Divi;1on Manager E. J. Janus, Sr. Electrical Engineer R. L. Kirven, Power Systems Division Manager
  • E. S. Kraft, Plant Support Manager i "F. Mogolesko, EQ Project Manager P. J. Moraites, Maintenance Planning Division Manager
  • H. 0heim, Dep. Engineering Manager L. Perfetti, Sr. Electrical Engineer

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J. Poorbaugh, Sr. QA Engineer W. Riggs, Mechanical Division Manager

  • R. E. Sherry, Maintenance Section Manager
  • C. Stephenson, Sr. Compliance Engineer
  • E. J. Wagner, Assistant to Vice President Nuclear i

4 U. S. Nuclear _ Regulatory Commission (NRC)

C. Carpenter, Resident Inspector T. J. Kim, Resident Inspector J. J. Lyash, Resident Inspector

'C. Warren, Senior Resident Inspector

2.0 Purpose

The purpose of this inspection was to review the licensae's actions taken

< in response to IE Bulletin 85-03, motor operated valve (MOV) common mode failures during plant transients due to improper switch settings and to i review the licensee's progrcm to assure the operational readiness of the motor operated valves covered under this bulletin. Tht: inspection also

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reviewed the status of several Electrical and Equipment Qualification opnn items.

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l 3.0 Background  !

On June 9,1985, the Davis-Besse Plant experienced a complete loss of main and auxiliary feedwater which was caused, in part, by MOV failures. This event resulted in IE Bulletin 85-03 that promulgated NRC requirements to assure the operational reaulness of MOVs in the high pressure coolant -

injection / core spray and emergency feedwater systems. The bulletin specified that licensees take the following action (a) Review and document the design basis for the operation of each valve, l including the maximum differential pressure expected dt.rtng normal and abnormal operatio (b) Using the above data, establish the correct switch settings for i torque, torque bypass, position limit and overload for each valve and  !

perform the modifications as needed, t ( t. ) Individual valves should be demonstrated to be operable by testing the valve at the maximum differential pressure based on the performance requirements. In the absence of differential pressure  ;

testing, justification should be provide l

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(d) Prepare and revise procedures to ensure that correct switch settings are determined and maintained chroughout the life of the plan t

(e) Submit a schedule to accomplish the above program including a final L submittal with the results of (b) through (d). .

Item (a) was reviewed by the NRC office of Nuclear Reactor Regulation [

(NRR) and the f.onclusions are documented in Section 4.4. The scope of [

this inspection was to review items (b) through (d).  ;

4.0 Boston Edison Response to IE Bulletin 85-03 (TI 2515/73)

4,1 Status of Commitments l

The licensee responded to the bulletin on December 31, 1986 This {

letter addressed 21 valves within the High Pressure Core injection l and Reactor Core Isolation Cooling Systems. As the Pilgrim Station j was in an extended outage, the valve testing wts not completed by the  !

co.uitment date of November 15, 1987. The liernsee requested an i extension to complete this activity within 90 days after full power operation is reached (Attachmens 1, Referenct- 2). This request was i granted by the NRC on April 14, 1988. (A.'a.hment 1 Reference 3). l

Using analytical techniques, the licensee has calculated the required {

thrust values and tested all the required MOVS using the MOVAT test  ;

equipment, The licensee plans to reconfirm the tested valves as soon j as the plant is in full power operation. A list of the valves i covered in this bulletin is provided in Attachment l t

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A 4.2 Switch Settings Item (b) of the bulletin requires that the correct switch settings for torque, torque bypass, position limit and overload for each valve be establishe These items are addressed belo Open Torque Switch and Open Bypass Limit

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This switch is normally used as a mechanical fuse to limit the

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mechanical thrust applied to the valve in the open direction. This switch is usually bypassed during the initial valve unseating which is the most challenging portion of the open stroke. Failure to set this switch to the required value or not bypassing this switch in the initial cpening stroke, can prevent the valve from openin BECo has chosen to bypass the torque switch in every safety related

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develop the reaximum available torque to open the valve. This is particularly of benefit if the safety function of the valve is to

open.

I Close Torque Switch The close torque switch is used to stop the motor rotation on the

! completion of valve travel in the close direction. Since this switch provides a normal control function and is exercised on every closuro

! stroke, this switch setting needs more careful consideration than the I open torque switch. The limiting requirenent of the close torque i switch is at tne end of the c osure stroke when the thrust

! requirements are the highest. The thrust at the point the torque l switch trips should equal the most limiting closure thrust require-I ment including the thrust needed to overcome the differential

, pressure across the valv Differential pressure testing using l process system pumps with appropriate data gathering and diagnostic

evaluation is the positive means of assuring the adequacy of the
torque switch set point. Other approaches based on s*milarity and j analysis may also be acceptable with sufficient basis.

l The licensee selected the manufacturer's recommendation for thrust

limits on the valve. Using the vendor's valve data and Limitorque i information, the licensee calculated the required torque for closing l

the valve when exposed to the maximum possible dif ferential pressure i acrocs the valve. MOVAT test equipment was utilized to confirm that J required thrust is developed at the valve sea The inspectors I verifad the test data on the thrust developed on the following valves, i

l 2301-3 HPCI Turbine Steam Supply

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2301-14 HPCI Minimum Flow Bypass

) 2301-36 HpCI Suction from Torus 1301-49 RCIC pump Discharge

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The final thrust developed on the valve seats exceeded the required thrust. The as found setpoints were in conformance with the licensee  :

documents. In Reference 2 (Attachment 1), the licensee has committed ,

to test the valves during power operation to confirm that torque  !

switches are set correctl The inspectors reviewed the valve manufacturer's data for the following valve Steam Isolation 2301-5 Steam Isolation to HPCI Turbine i 2301-6 HPCI Pump Suction from Condensate Storage Tank l 2301-8 HPCI Pump Discharge Valve  ;

i The valve rating for thrust limit was significantly above the  !

required thrust. No discrepancies were observe [

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C_ lose Torque Switch Bypass  !

The close torque switch bypass acts in the same manner as the open torque switch bypass; however, contrary to its counter part function, t it normally bypasses the torque switch during the lightest duty  !

portion of the stroke, the beginning of the closing stroke. The ise i of this switch is not critical; however, if utilized it should be set  !

to operate during the initial part of the stroke, to assure that  !

valve closure is not previnted by the torque switc !

t BECo controls the torqte switch operation based on the safety i fuqtion. When the safaty function of the valve is to close, the l torque switch is bypassei for 93 percent of the strok This ,

approach makes the full t wque of the motor available for completing the significant part of the strok If the valve closure is not a safety function, the torque switch is bypassed only during the ,

initial stroke of the valve and thereafter it remains in the circuit, t No deficiencies were identifie ;

Open Limit Switch This switch provides the control function for determining the upper limit of the valve stem travel in the open direction and stops the motor rotation by opening the circui The setting of this switch must assure adequate valve opening and should prevent back contin Valve backseats provide a soal that is redundant to the valve packing in order to allow valve packing replacement without the need to drain down the process system. Using the motor power to backseat, can and has caused valve stem shearing and stem thread twisting. Therefore, it is important to set the open limit switch away from the back seat with enough margin to allow for motor deenergization and inerti BECo has set the open limit switch such that the valve does not back seat by inerti No problem was identified with +his arrangemen m

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Close Limit Switch

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This switch is usually used with the close torque switch in series s for over-torque protection. For high speed operators, where torque switches cannot react in sufficient time, the close limit switch deenergizes the motor and the remaining inertia forces seat the valv BECo is not utilizing the close limit switch to deenergize iht motor for valves covered under this bulletin. All the valves in the scope of this bulletin are seated using the torque switches.

Open/Close Indication

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A red light provides a valve open signal. This light is taken from

the close rotor limit switch which is set to actuate very close to j the end of valve closure. A green light provides a valve c1
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, signal and is taken from the open rotor limit switch actuatio The

green light will len off when the MOV is in the full open position,

and the red light will turn off when the MOV is in the full closed j position.

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a Most of the PNBS MOVs are equipped with only two rotor The

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precision for position indication is less significant than the torque switch bypass function. Therefore, the light indications are not

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exact but within 5 to 10 percent. No discrepancies were observed.

) Thermal Overload Relay Thermal overload relays are used to protect motor winding insulation I from breakdown during overload conditions. Devices used appear to l uniformly consist of heaters at the motor control center which trip a l heat sensitive relay, the contacts of which either interrupt current I to the contractor closure coil (which stops the motor) or initiates j an overload alarm, or both. Where t'.ermal overload relays stop operator mo . w ation on trippig , the heaters must either be sized

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to prevent inadve , 'N ;t9 ppd g the motor or the overload relay 2 l

l must be bypassed when mu, ' sration is important to safety. They l

should also be sized to protect the motor windings from thermal 4 damag Regulatory Guide 1.106, thermal overload protection for

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electric motors on motor operated valves provides guidelines on the design criteria for thermal overload Designs that area being used at this time to eliminate the threat of

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inadvertent motor trips include: (1) removing the heaters or relay l contacts from use; (2) using the relay contacts for alarm only; (3)

! bypassing the relay contacts during all operating modes except when a j valve is being exer sed for testing; (4) bypassing the relay

contacts only during the presence of an automatic safety actuation j signal; and, (5) oversizing the thermal overloads.

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The BECo criteria on thermal overload relay sizing was reviewed during inspections 88-27 and 88-08. The inspectors reviewed the

electrical schematic diagram for the RCIC valves and concluded that j thermal overloads do not serve a control function but only an alarm j function. All the MOVs covered under this bulletin, including the G

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operated MOVs were verified by the licensee to only alarm for a thermal overload condition, 4.3 Demonstration of Operability

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This involves demonstrating the valve to be operable by testing the i valve under maximum differential pressure after changing the f

inoividual valve settings as appropriate based on the design bases.

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In the absence of testing with full differential pressure across the valve, a justification is to be provided. The use of a MOVATS data i base to set the torque switches for a particular type of valve is considered as an acceptable approach to exclude differential pressure testing, provided this type of valve bas sufficient test data to i

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establish similarity. However, a suitable test is needed to establish that the desired force is available at the valve seat for

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closure.

i i BECo has calculated the required torque switch setpoint using the I Limitorque information. The licensee plans to conduct a differential

! pressure testing upon recovery f rom the outage. Currently all the MOVs covered under the bulletin have been test with the MOVAT

equipment at the required torque switch setpoint During the inspection, the licensee was unable to produce the test records documenting the actuation of limit switches. However, the licensee maintenance procedures provide clear directions to set these l switches at the desired configuration. The records on maximum thrust i

developed was reviewed in detail. The licensee tabulation of thrust i values for all bulletin valves concluded that sufficient thrust was

) available at the valve seat during closing. As the open torque j switch was bypassed during the safety function, this switch setting l

was not verified.

i No discrepancies were identified.

i 4.4 NRC Review of the Licensee Submittal J

As requested by action item e. of Bulletin 85-03, "Motor-Operated l Val e Common Mode Failures During Plant Transients Due to Improper l

Switch Settings," the licensee identified the selected safety-related valves, the valves' maximum differential pressures and the licensee's program to assure valve operability in their letters dated May 9 and

December 31, 1986, and November 13, 198 NRC review of these

{ responses indicated the need for additional informatio This is i documented in an NRC letter to BECo dated March 25, 19S l

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NRC review of the licensee's May 6, 1988, response to this request for additional information indicates that the licensee's seleution of the applicable safety-related valves to be addressed and the valves'

maximum differential pressures meets the requirements of the bulletin '

and that the program to assure valve operability requested by action item e. of the bulletin is acceptabl ,

The NRC reviaw of the final response required by action item f, of

the bulletin will be addressed in a future inspection repor .5 Main +enance and Procedures 1 + o lletin requires that licensees prepare or revise procedures to e.. ~ . hat correct switch settings are maintained throughout the life of the plant and also to ensure that applicable industry .

recommendations are considered in the preparation of the procedure, l

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The inspectors reviewed the procedures listed in Attachment 3. The

licensee had revised these procedures for maintaining the limit and torque switch settings. The torque switch setpoints for all the safety related vcives are addressed in licensee drawings listed in
Attachment 4.

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A walkdown was conducted to inspect valve MOV maintenance activities.

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Where practical, the inspectors verified the grease level in the main

gear case and looked for lubrication of the valve stems. These were j found to be sufficiently lubricate The licensee technicians and 1 their staff were knowledgeable in the operation and maintenance of j the valves.

I The inspectors reviewed the post maintenance testing of MOV The l licensee is currently timing tne valve stroke to establish t operability after minor maintenance and tightening of the packin [

) The ',1censee concurred with the inspectors observation that valve t stroking does not completely establish valve operability, since valve

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stroking is not performed with a differential pressure across the ;

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valve, The licensee is plcnning to look into this matte They plan t

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to consider industry experience with this issu [

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The inspecturs observed that licensee procedures do not identify the f i circumstances which prompted the retesting of the valves covered ;

under this bulletin. Certain corrective and preventive maintenance i

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activities can influtnee the as-left conditions of the torque switch

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setting. A replacement of the torque switch or spring pack will lead

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to changes in the availthle terque for closing / opening the valv !

i The inspectors inquired if any of the subject valves had undergone l maintenan;e activities that can potentially affect the torque :

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available for valve function. The licen;ee review of maintenance

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records indicated a torque switch replacement in valve 1301-16. The inspectors questioned the licensee regarding their planned actions to l

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verify the capability of valve 1301-16 to perform its safety functio The inspectors discussed the above item with the licensee management and indicated the need for the operability of valve 1301-16 to be addressed before plant restar The maintenance department currently plans to retest this valv The licensee committed to develop the guidelines establishing tha need for retesting valves that have undergone certain maintenance activities and sensitizing the key maintenance personnel of the need for this retestin This is an unresolved item pending NRC review of the new test results to establish operability of valve 1301-16 and the development of specific conditions which would require retesting of valves that are covered in the bulletin. (50-293/88-32-U.1)

No other deficiencies were identifie .0 Followun Of Previous Inspection Findings 5.1 (Closed) Unresolved Item (88-08-03) Undersized Starter During a previous special inspection of electrical power systems, NRC inspectors identified a contactor installed in MCC cubicle B1735 which was NEMA size I whereas the E10, Revision 12 drawing indicated a NEMA size 2. This contactor misapplication was identified as an Unresolved Item pending further NRC review of the licensee's actions to review other potential misapplications of contactors and the cause of this discrepanc According to NEMA standards, size 1 contactors can be used with 460 volt motors having ratings not exceeding 10 HP and size 2 contactors with 460 volt motors having ratings not exceeding 25 Hp. The load served by unit B1735 is a 20 HP motor for drywell unit cooler V-AC-206A1. Accordingly, a NEMA size 2 contactor is required for this application. This MCC was procured by Bechtel Engineering via a purchase order for BECo. A size 2 starter was ordered. However, a size 1 starter was supplied by the manufacture PNPS Q? Manual Section 7 requires that a receipt inspection of purcha Jipment be performed according to approved procurement docum Failure to use correctly sized motor starters as specified oy design drawings constitutes a violation of 10 CFR 50 Appendix 8 Criterion VII which requires that measures be established to assure that purchased en.uipment conforms to procurement document This is a violation (50-293/88-32-02).

Subsequent to this NRC finding, the licensee initiated a potential Condition Adverse to Quality (PCAQ) #NED-88-022 which documented the discrepancy between field conditions ind as-built drawing BECo's Nuclear Engineering Department (NED) addressed this discrepancy and

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. documented its evaluation in ERM 88-647. The apparent cause for the

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deficiency is that a size 1 starter was improperly shipped from the manufacturer Nelson Electric. An extensive document search by the licensee of the corresponding MCC procurement documents and receiving ,

records indicate that the MCC purchase order required a size 2  !

starter but a size 1 starter was erroneously shipped by Nelson '

Electric. A test data sheet for MCC cubicle B1735, dated April 7, 1972, indicated that a size I starter was installed in the cubicle at L that time. The licensee, therefore, determined that Nelson Electric .

incorrectly supplied a size 1 starter and receiving inspections by }

Bechtel did not note this erro :

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NED issued Field Revision Notice (FRN) 87-80-46 to replsce the size 1  !

starter in HCC cubicle B1735. A walkdown was performed of the ,

remaining safety-related MCCs to ensure that the as-built conditions agree with the design documents. No additional discrepancies were ,

identified. NED has informed Nelson Electric uf the deficiency in '

the procurement process which contributed to the proble In addition to the field walkdown of as-built starter sizes to the l design documents, NED reviewed the current motor sizes on the  ;

safety-related MCCt to verify that the existing starters are sized i properly. As a re tult of this risview, five (5) additional starters l were changed from a size I to size 2. These changes were due to past  ;

PDCs that made minor changes in the mo ar sizes that were being fed l from the MCCs. These changes in motor sites were marginal. However,  !

they were necessary to confere with the industry standards for sizing .

motor starter l

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The NRC inspectors reviewed the licensee's evaluation of the  !

undersized contactor during this inspection period. The licensee l initiated adequate corrective actions and evaluated the circumstances  ;

to determine if other similar misapplications were present in ,

safety-related Motor Control Centers,  !

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Based on the licensee's corrective r.ctions to prevent reoccurrence i and results, this violation is considered close .2 tClosed) Unresolved Item (87-53-01.1) Licensee Actions to Improve

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Ability to Respond to Future LOOP Events: During the Augmented Inspeuten Team (ATT) re/tew of the November 12, 1987 loss of e off-site power (LOOP) event at PNPS, the licensee identified several l actions that would be implemented to improve the stations ability to i respond to future LOOP events. These actions included (1) '

installation of a station blackout diesel generator (SBDG); (2)

installation of a backup instrument air suppiv; and, (3) installation of additional instruments to analyze switchyard transient Review of the above actions and inspector observations are described  :

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e 11 Installation of Station Blackout Diesel Generato As part of the PNPS Safety Enhancement Program (SEP), the licensee has installed an additional Standby Diesel Generator (SBDG). This non-safety related DG still provide a source of ,

on-site power to the 4.16 kV safety buses A5 and A6. This DG supplies power to the buses through bus A8 concurrent with a '

failure of either one or both Emergency Diesel Generators (EDG).

The SBDG, rated at 2000 Kw, can provide sufficient power for one ECCS pump and its associated support systems required for a LOOP event. Two 20,000 gallon fuel oil tanks provide sufficient ,

supply to run the SBDG for one week. The NRC inspector reviewed PNPS Procedure No. 2.2.146 "Station Blackout Diesel Generator" Revision 1. The station procecure addresses the initial lineup, standby status, operation and restoration of the SBDG. lhe licensee has completed installation and pre-operational testing >

of the SBDG, The inspector performed a walkdown of the SBDG during this inspection and observed the diesel and associated equipment to be well-maintained and ready for operatio . Installation of Back-up Instrument Air Suppl During the LOOP event, the licensee determined that an additional, independent back-up air supply was needed to enhance the existing Instrument Air System. The back-up air system can provide an additional source of air during times when the existing system is not available due to maintenance. A portable Atlas Cupco 900 SCFM compressor is staged outside the Turbine Building truck lock to provide the emergenr.y back-up air suppl The compressor can be conner.ted to the instrument a;r header through a permanent connection between air compressor X-111 and air receiver T-154. The back-up instrument air supply will be

, connected to the permanent tie-in connection via a 4" flexible air hose. The back-up air supply connection will be isolated during normal operation. The NRC inspector reviewed the following PNPS Procedures:

2.2.36 "Instrument Air Systems" Revision 17

- 5. "Loss of Instrument Air" Revision 11

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The above procedures provide instructions for the operation of the portable air compressor and the systematic isolation of portions of the air system to mitigate the effects of a loss of instrument air event. At the time of this inspection, the licensee had completed installation of the back-up air system but had not performed a pre-operational test of the system. The licensee is tracking this test. The test is scheduled to be complete prior to rester . Installation of additional instruments to analyze switchyard transient I l

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As part of the SEP, the licensee identified the need for improvement in the recording of switchyard parameters to increase the ability to reconstruct and analyze transient

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events. The licensee proceeded to install an Automatic

Transient Recording System (ATRS). The system will enable the licensee to evalcate and analyze tra.nstents such as those experienced during the LOOP event of 198 Installation of the ATRS is complete and is in operatio During review of the above items, no deficiencies were identifie This item is considered close .3 (closed) Unresolved Item (8'/-36-02) Operation of MOVs at High Voltage: During a previous NRC inspection the NRC questione3 the licensee on the effect of having 520 volts on 480 volt buses. The Inspector was concerned regarding she effect of high voltage on MOV 1 operating times, plant instrumentation, and calibration of protective relays and breaker '

The NRC inspector reviewed the licensee's evaluation of the NRC's concerns. Results of the review are described belo . Effect of High Voltage on MOV Operating Tim Elevated AC voltages have negligible effect on motor RPM and therefore will not significantly affect valve stroke time. An

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increase in operating voltage (110%) results in a decrease in the slip and a nsgligible increase in RPM of about 1%. There-fore, if an induction motor is operating at rated voltage or at an overvoltage of 110%, there is no significant change in its RFM. The valve stroke time can therefore be expected to remain the same at either operating voltage. Since the operating time of the MOVs is relatively short, any increase in motor heating

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will not exceed the motor's temperature rise capabilit . Effect of High V,ltage on Plant Instrumentatio The 120 volt AC control circuitry has a 120 1 10% (132 y max)

4 voltage rating. Using a 480/120 AC bus voltage ratio, and

! extrapolating to a higher voltage of 520 volts at the MCC buses, corresponds to a voltage of 130 volts at the instrumentation buses. This is a conservative assumption in that the instrumentation buses would probably have a lower voltage than

130 volts due to the 480/120 volt transformer impedance and circuitry load losses. Typical 120 V instrument relays have ratings of 120 V ! 10%. Therefore, the maximum rated voltage allowed (132 V) is higher than the expected worst case voltage

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13 Effect of High Voltage on Protective Relay / Breaker Calibration Operation of protective relays and breakers is not affected by

, higher voltage Since overcurrent is the principal parameter in overload / fault current protection systems, protective equipment function is independent of system vultag No deficiencies were identified during this revie This item is close .4 (Closed) Violation (83-08-01) c 11ure a To Perform Periodic Calibration / Testing of DC Ci/cuit Breakers: This violation pertains to the failure of the licensee to perform periodic calibration / testing of DC circuit breakers as required by PNPS Technical Specification 6.8A. During a previous NRC inspecticn (88-23), the NRC staff reviewed the licensee's response to the notice of violatio The licensee developed a testing program for a representative sample of all types of safety-related DC breakers installed at PNP Testing included breakers of varying ratings and types. A sample of 44 breakers were teste During the previous NRC inspection, the NRC staff reviewed the licensee's technical analysis and basis used to achieve the breaker test acceptance criteri During this inspection, the NRC inspector reviewed the de breaker test results to verify that all the tested breakers met the acceptance criteria. All tested breakers met the acceptance criteria, No deficiencies were identified during the revie The licensee previously committed to develop and implement a long-term d- breaker surveillance program. The licensee has committed to implement this program by October 1, 198 Based on the above test results, this violaston is considered close .5 (Closed) Unresolved Item (SS-23-01}_Unjdentifiable Wiring in

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Limitorque Motor Operators:

During a previous NRC inspectio:l (SS-23), NRC inspectors reviewed the licensee's corrective actions in response to Information Notice 86-03 regarding the unquali.~ied internal wiring in Limitorque valve Results of the review indicated that the licensee's corrective actions to address the qualifications of Limitorque internal wiring was insufficient in that the inspectors observed three unidentifiable wires in valves located inside containment. The presence of unidentifiable wiring was documented as an Unresolved Item (83-23-01)

pending licensee evaluation of the causes of the discre-sncy and the corrective action _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . .

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a In the previous inspection, the NRC inspectors observed a red jumper wire on the terminal block inside the Limitorque compartment of valve .

MO-202-5A which could not be identified. The licensee presented

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documents which traced the wire to Gauge 12 SIS GE Vulkene Suprem Inspection of valve MO-202-5B revealed jumper wires located on the terminal block and limit switch fingerboard which could not be identified. These jumper wires were required to be either qualified Vulkene Supreme SIS or qualified Rockbestos Firewall SIS. However, at the time of the NRC inspection these wires could not be established as qualified and their traceability could not be  ;

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Subsequent licensee inspections of MOVs listed in the EQ Master List

(EQML) revealed that Rockbestos Firewall EP wire was installed in six l (6) MOVs. Rockbestos Firewall EP has limited qualification inside '

i the drywell to a peak temperature of 150 F or less. This peak  ;

i temperature is below the peak temperature for which the MOVs are  !

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required to operate during accident condittens. Four (4) of the six valves identified with this type of wire are located inside the d rywell . The six valves are listed belo,<:

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  • MO-220-1 MO-1001-23B  :

MD-1001-268 l

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  • MO-1001-63
  • MO-1301-16 i
  • MO-2301-4

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  • Denotes valves located inside the drywel ;

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BECo procedure NOP 84A9, "Equipment Qualification Program," Revised February 12, 1988, describes in part the controls for demonstrating l and documenting the qualification of equipment and the maintaining of l EQ Document Files. 10 CFR 50.49(f) requires that each component be i environmentally qualified based on testing with identical or similar [

equipment under expected worst case environmental conditions to show i that the equipment to be qualified is acceptabl Failure to install l qualified wires in MOVs for use inside the drywell and failure to (

establish qualification of all MOV wires at the time of the NRC  ;

inspection constitutes a violation of 10 CFR 50.49(f). This is a f violation (50-293/88-32-03).  !

The NRC inspectors reviewed the licensee's corrective actions in resolving the NRC inspectors' findings and their subsequent inspection findings. Licensee actions and inspectors' observations I are described belo [

i Licensee actions included initiating a Potential Condition Adverse to i

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Quality (PCAQ) report #NED 88-095 which resulted in the development, of an inspection program covering all 70 EQ Limitorque MOV !

Inspection attributes included detailed wiring requirements to i

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1 confirm qualification and identification of wiring requiring replacement. All suspect wires were reoutred to be replaced with Rockbestos Firewall SIS, traceable to BECo qualification report During the inspection of the EQ valves, the licensee observed the jumper wires identified durirg the previous NRC inspection as well as other wiring deficiencies. Licensee findings are as follows:

, The licensee observed the two jumper wires installed in valve MO-202-5B which could not be identified at the time of the previous NRC inspection. The unidentifiable white wire was

.! removed for inspection. Examination of the removed jumper was l made together with other removed similar white jumper wires installed by Limitorque. These wires were all similar in size,

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. color, and texture. Some of these wires had partial markings

] which are part of the marking found on Rockbestos Firewall SIS

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qualified wir Rockbastos indicated that they manufactured qualified Firewall SIS wire with white insulation. Rockbestos informed BECo that based on the comparison of the installed wire

to marked qualified wires, they concluded that the found jumpers are Rockbestos Firewail SIS qualified wir 'hs unidentifiable gray wire with red line also was replace Inspection and comparison of wires with this color to identified marked wires established that this wire was qualified Vulkene Supreme SIS. During the course of licensee's inspection, suspect jumper wires with the following colors were observed

red / pink, gray with red line, gray with black line, orang These wires were later identified to be either qualified Rockbestos Firewall SIS or qualified Vulkene Supreme SI . Black celored wires were observed in six MOVs. Some of these wires were readily identified as Rockbestos Firewall E The licensee reviewed Equipment Qualification Evaluation Sheets to determine whether these wires were qualified for its as-found applicatio Review of these documents as well as Maintenance Requests, Material Receipt Inspection Reports, and QC Inspection Reports verified that these wires were Rockbestos Firewall E However, Rockbestos Firewall EP wire has limited environmental qualificatio It is qualified for EQ applications outside the drywell. Four of the six MOVs having this limited type of wire are located inside the drywel The NRC inspectors reviewed WYLE Laboratories Nuclear Environmental Qualification Report N CAB-20 which established the qualifica'. ion for Rockbestos Firewall Ep wire for use at PNPS. This report established its qualification for outside the drywel All of the above suspect wires were replaced with qualified Rockbestos Firewall SIS during the licensee's inspectio The NRC inspectors reviewed licensee documents to determine woen the Rockbestos EP wires were installed within the drywell MOVs and

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whether these wires were ever in use. Review of several Maintenance Requests and QC inspection reports indicated that these wires were ,

installed during the present plant outage and therefore were not in '

service during plant operation. Documents reviewed are listed in Attachment ,

The licensee implemented a plan to determine the extent of the use of  !

Rockbestos Firewall EP wire. A review of all Safety Related (Q) '

purchase orders (PO) indicated that only two Q Purchase Orders had been placed with Rockbestos for the subject wire. These two P0s were (

made by BECo and were Nos. 37291 and 56791. Review of these P0s  !

indicted that this type wire was used for fire protection tasks, l which are r.on EQ applications, and for the upgrade of MOVs. Wire used for MOV applications, from P0 No. 37291, was withdrawn from the  !

warehouse during or after the September 1987 time frame. (Review of MRs for the four drywell valves also traced the installed wire to  !

this purchase order.) A search of the cable and raceway program by cable code and a review of the master list equipment, to determine if  !

"EP" wire was installed in other EQ applications other than MOVs, "

indicated that no Rockbestos Firewall EP wire was used as a cable in any EQ application. In addition, jumper wires of this type are not i used within the drywell for EQ applicatio The NRC inspectors reviewed PNPS Procedure No. 1.5.3.1, "Maintenance ,

Work Plan" which establishes the measures to be used fe,r the i preparation, review, approval, and issuance of a Maintenance Work i Plan. This procedure has been revised to include further instructions and requirements for the review of EQ work activitie EQ work activities are reviewed by engineering in the planning ,

package and the EQ requirements will be documented in EQ Supplement Sheet (s). 1 The licensee reviewed the inadequacy of QC inspections during the -

installation of the unqualified wires in MOV Review indicated that t when QC inspectors are observing the work activity, they do not I verify the wires to the source to confirm if these wires are indeed I the correct wires in accordance with EQ requirements. QC inspectors l are now instructed as to the types of environmentally qualified wires ,

available and to visually verify all installed components to the '

source document and that they are in conformanc During this inspection period, the NRC inspectors reviewed the licensee's extenshe effort to remove all the potential concerns on i unqua'ified wiring in EQ equipments. The corrective action j addressing the unidentified wires was determined to be adequat Licensee actions to prevent reoccurrence, including engineering review of EQ work activities and additional training of vc inspectors, were also determined to be adequat Based on the above licensee's corrective actions and subsequent NRC review, this violation is considered close _ _ _ _ _ _ _ _ _ _ _ _ _ _ - .

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5.6 (Closed) Unresolved Item (87-27-05) Motor Operated Valve Preventive and Corrective Maintenance Program. This item deals with the following items:

Inadequate use of Torque switch in closing circuit;

  • Lack of instructions to prevent back seating;
  • Unbalanced Torque switches and lack of procedural control on balancing torque switches;
  • Spring Pack packed with grease;
  • Improper splice on MOV-1001-7C and MOV-1001-7 Based on the extensive problems icentified in MOV maintenance area, the licensee used a Limitorque contractor and performed a ce elete overhaul of all the safety-related and some of the rior-saf ty * . ..d valves. This work was done according to the revised BECo precsdere The inspectors reviewed the summary document "PNPS Motor Operated Valve Program RF07", dated May 9, 1988. The work involved the following specific activitie . One and ten minute meggar test of motor Limit Switch Compart.nent inspection:

a condition of all gaskets and seals for compartment cover and switches;

  • condition of switch contacts and phenolics;
  • switch materials (EQ grade as applicable);
  • condition of lugs and wiring (replacement as required for EQ valves);
  • torquing of terminations;
  • contact and phenolic inspections;
  • torque switch balancing; e adjustment of spring cartridge cap collar (if applicable);
  • verification of permanent open tcrque switch bypass; (if applicable);
  • switch functional check: feed to open/close permissive;

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  • switch setting: per manufacturers recommendations or past MOVATS;
  • electrical stroke test to verify positive closure, T-drain blockage (E0 valves inside containment) Condition and level of main and clutch housing grease Hold down bolt torquing (tightness check) Staking of stem nut locknut (rising stem, non-rotating only) Stem lubrication and thread condition 1 General inspection for external gasket and seal leakage The licensee procedures were proven te be sufficient to maintain the ;

MOVs during this wor Torque switc5 .etpoints are currently controlled through the drawings liJted in Attachment 4. Based on the inspectors observation of the valves discussed in Section 4, this item is close The insoectors reviewed a Limitorque contractor report (PNPS Motor Operated Valve Program RF07) that addressed several valve conditions which rendered the valve inoperable due to spring pack problems, some valves that containea improper splices and unqualified material in environmentally quclified MOVs. It was determined that the corrective actions are complet .0 Unresolved Items Unresolved items are matter for which more information is required in order to ascertain whether they are acceptable, violations, or deviation One unresolved item is discussed in Section 4.5 of this repor .0 Exit Interview At the conclusion of the inspection on September 16, 1988, the inspectors met with the licensee repress.itatives denoted in Section The inspectors summarized the scope and findings of the inspection at that tim No written mater al was provided to the licensee by the inspector '

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ATTACHMENT 1 REFERENCES Licensee letter f rom James M. Lydon to Thomas E. Murley, NRC, dated i December 31, 198 I Licensee letter from R. G. Bird to Document Control Desk, NRC, dated November 13, 198 ! NRC letter from Daniel Mcdonald, Project Manager to Ralph E. Bird, Boston Edison Company, datted April 14, 198 ;

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A W c h cJ- 2- Py .s 4 z s9V 'JATA M -

j Size (In) Limitorque Torque .

Design'Sasts sees Operating * Switch lyCI 51stee valve Battne(lb) Oserator Valve Function A P (PSIP A P(PSI) (hen /Closs

Jammered 80-2301-3 10s4 $NS-1 Steam Admission Valve 1150 1104/1104 Open Volan - Gate 600

E2301-4 los8 SNS-2 Stoasi Line Isolation valve 1850 ,1104/1104 Open volan - Gate 900

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ND-2301-5 loss 5s8-1 Steam Line Isolation Valve 1150 1104/1104 Open

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Velen - Gate 600 sed-2301-6 16 5s6-0 Condensate storage Tank 60 25/38 Open Powell - Gate 150 Section valve 86-2301-8 14:10 SMS-1 Injection valve 1500 1230/1302 Open Anchor - Gote 900 8c-2301-9 14s10 See-I Injection Test Valve 1500 1230/1302 Open Ancher - Gote 900 ac.2301-10 10 58 8 - 2 CST Test Asturn Valve 1500 1290/1337 Open WeIen - GIobe 900 80-2301-14 4 SMB-0 Mlaisus Flow Sypass 1500 1327/1355 Open velan - Globe 900 Isolation valve

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seO-2301-35 16 $ss-O Suppression pool Section 60 26*/26 Open pomell - Gate 350 Isolation valve sc-2301-36 16 SMS-00 SuperessIon Pool SectIon 60 27*/27 Open Anchor - Gate 150 Isolation Valve

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  • V41ees are for both open and close position * Calculated maalaum operatin5 pressures based on DR Ouner's Group Repor ' for additional conservatisa, lacreastag pressere due to check valve leakage will be assumed resulting in a section line pressere of 97 pst. Realizing this possibility, the section line relief valve will be set louer.

l or the valves / operators will be readjusted for 100 pst differential.

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A thche.d- 2- Pag z e z- o

SOW DATA $4pSthSY (Cont'e . .

Torque Stre(In) Llettorgue Design' Basis Mas Operating * 5=ltch RCIC 51ste. Valve mattne(16) Operator Valve Function op (PSI) & (PSI) Geen/Close Jameered

$se-C) Steam Line Isolation Valve 1250 110411104 Open 10-1301-16 3 I

volan - Gate 600 go-1301-17 3 SMS-000 Steam Line Isolation Valve 1250 , 1104/1104 Open Velas - Gate 600

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Condensate Storage Tank Go 25/36 Open -

10-1301-24 6 SMS-000 pomell - Gato 150 Section valve 6 588-000 Suppression pool Section 60 27'/27 Open 30-1301-25 Velas - Gate 150 ,

Isolation valve 6 5MS-000 Suppression Asl Section to 26'/26 Open 30-1301-26 pour.Il - Gate 150 Isolation valve l Injection Test Valve 1500 1238/1345 Open 30-1301-48 e SMS-00 Pome 11 - Gate 900 1400 1238/1345 Open IO-1301 4g 4 SMS-00 Injection Valve  :

pomell - Gate 900  ;

1400 1301/1358 Open 10-1301-53 4 5s6-0 CST Test Return Valve ,

powell - Globe 900 ,

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1500 1340/1377 Opos 2 SMS-00 pflaleus Flow Sypass 10-1301-60 pomell - Globe 600 Isolation valve 1850 1104/1104 open 30-1301-61 3 5se-00 Steam Admission valve romeli - Globe 600 I 60*/28 open 10-1301-62 2 SME-coo Coollag lester to Turbine 75 pomell - Globe 600 Mcessortes

" Walmes are for both open and close position .

  • Calculated mesleum operattag pressores based on ges (hener's Group Repor * For additional conservatise, lacreasing pref svre due to check valve leakage will he assumed resultlag la a section line pressere of 95 psl. Reallalet this possibility, the suCtles llae relief valve will be set lower or the valvestoperators w1Il he readjusted for 100 pst differeetta " This value 15 hased on demonstrated operaf,111ty during pump surveillance testlag, and a control valve located upstree _ _ _ . _

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l ATTACHMENT 3 M0V PROCEDURES 3.M.1-11.1 EQ Maintenance Repair / Replacement, Revision 10 3.M.4-10 Valve Maintenance, Revision 10 8.Q.3-8 Limitorque Type SB/SMB Valv6 Operator E0 Maintenance, Revision 5 3.M.3-24.1 Limitorque Type SM3 Valve Operator Removal, Revision 5 3.M.3-24.2 Limitorque Type SMB-000/00 Motor Operator Overhaul, Revision 3 3.M.3-24.3 Limitorque Type SMS-0 Through-3 Motor Operator Overhaul, Revision 2 3.M.3-24.4 Limitorque Type SMB-5 Motor Operator Overhaul, Revision 1 3.M.3-24.5 Limitorque Type SB/SMB Electrical Checkout and Adjustment, Revision 10 3.M.3-24.6 Limitorque Type SMB Valve Operator Installation, Revision 4 3.M.3-24.7 Limitorque Type 58-00 Through SB-3 Valve Operator Disassembly / Removal, Revision 1 3.M.3-24.8 Limitorque Type 58-00 Through SB-3 Valve Operator Reassembly / Installation l

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ATTACHMENT 4 ORAWINGS i

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M-MOV 1 Motor Operited Valves Information Table Revision E-1 M-MOV 2 Motor Operated Valves Information Table Revision E-0 ;

M-MOV 3 itotor Operated Valves Information Table Revision E-1 M-MOV 4 Motor Operated Valves Information Table Revision E-0

M-MOV 5 Motor Operated Valves Information Table Revision E-1 M-MOV 6 Motor Operated Valves Information Tabis Revision E-0 ;

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ATTACHMENT 5

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OOCUMENTS REVIt'WED r

PNPS Report No. 8SXE-2ER-Q, "Assessment And Confirmation Of Environmentally  ;

j Qualified Limitorque Motor Operator Internal Wiring." [

t i BECo Nuclear Organization Procedure 84A9, "Equipment Qualification Progrnn." l

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BECo NED Memorandum 88-447, "Limitorque EQ Master List Motor Operator Environmental Qualification Inspection 3 Requirements."  ;

i WYLE Laboratories NEQ Report 47066-CAB-20 "Qualification Verification Report L On Rockbestos Firewall EP Cable For Use In Pilgrim 1 Nuclear Power Station."  :

i PCAQ #NED 88-03 !

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Engineering Service Request (ESR)88-516. "PCAQ NED 88-0S5, IEN 86-03, EQ  !

Limitorque File."

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l ESR Response Memorandum (ERM)88-675.

BECo NED Telecon record with Rockbestos Company, Dated July 20, 1988.

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Maintenance Requests: i-86-10-121 -88-23-76 f-88-10-22 -8S-23-81 i-88-13-54 -83-23-84  ;

j -88-23-66 ~

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BECo NED Doc.ument No. NED 88-516 "Maintenance Work Package Review Feedback." -

i Equipment Qualification Evaluation Sheets: i

1-Cable-Rockbestos Firewall EP (0.C.)

-MO-220-1  !

-MO-1091-63 l-MO-1301-16 i-MO-2301-4 l Material Receipt Inspection Report No. 81-75 I BECo Purchase Order No. 3729 f I

QC Inspection Report No. IR 87-1-59 l l

BECo Oeficiency Report No. 180 (

l PNPS Procedure No. 1.5.3.1, "Maintenance Work Plan."

l QC Instruction No. 5.01, "Quality Control Review of pNPS Maintenance Requests (

and Maintenance Work plan Packages."

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