ML18059A931
| ML18059A931 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 04/08/1994 |
| From: | Rogers D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9404150058 | |
| Download: ML18059A931 (13) | |
Text
consumers Power l'OWERINli MICHlliAN-S PIUlliRESS Palisades Nuclear Plant:
27780 Blu.e Star Memorial Highway, Covert, Ml 49043 April 8, 1994 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 David W. Rogers Plant Safety and Licensing Director DOCKET 50-255 - LICENSE DPR PALISADES PLANT - RESPONSE TO NRC INSPECTION REPORT 94002, SERVICE WATER OPERATIONAL PERFORMANCE INSPECTION, UNRESOLVED ITEMS AND WEAKNESSES A Service Water System Operational Performance Inspection (SWSOPI) was conducted at the Palisades plant over the period from Ja~uary 10 through February 11, 1994.
The report addressed a number of unresolved issues and weaknesses for which we were asked to provide a response addressing eath of these items including our proposed corrective actions. A specific ~ate for providing this response was not requested in the inspection report letter.
Discussions with the NRC inspection team leader resulted in agreemerit on a response date of April 8, 1994.
A ptoject team has been formed as a followup to the SWSOPI Inspection.
The team is presently developing a project plan which will at a minimu~ address completibn of the actions identified as followup to th~ NRC Inspection and a margin enhancement plan for.the service water system~
Attached to this letter is the individual responses to each of the unresolved items and weaknesses identified in the March 4, 1994 inspection report.
David W Roger~
Plant Safety and Licensing Director CC:
Administrator~ Region Ill, USNRC Resident _lnspectori Palisades Attachment
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9404150058 ~4646~
PDR ADOCK 05000255 Q
PDR A CMSCNE7?GYCOMPANY
ATTACHMENT Consumers Power Company Palisades Plant Docket 50-255 RESPONSE TO NRC INSPECTION REPORT 94-002 SERVICE WATER OPERATIONAL PERFORMANCE INSPECTION
. UNRESOLVED ITEMS ANO WEAKNESSES April 8, 1994 *.
SERVICE WATER OPERATIONAL PERFORMANCE INSPECTION UNRESOLVED ITEMS AND WEAKNESSES UNRESOLVED ITEMS Unresolved Item 50-255/92028-03(DRS) 1.
Use of firewater to provide backup water supply for auxiliary feedwater (AFW).
The NRC's concern was based on the lack of an analysis or testing to verify the fire water system's capability to provide backup water to the AFW system.
- The licensee committed to complete an analysis to document the fire water syste~ adequacy under action item request (AIR) A-PAL-92-098.
CPCo Response As part of the follbwup to NRC Inspection Repcirt 92028, we were asked to respond within 60 days of the date of the report, to.Unresolved Item 3.
Our March 29, 1993 lettet to the NRC pr~vided our plans for completion of the follow-up actions for this unresolved item.
In summary, based on enginee~ing judgement we believe that the fire water pumps and interconnecting system can provide the needed water to the auxiliary feedwater pumps suction. Action.
Item Record -A-PAL-92-098 was written to provide an analysis demonstrating the ability of.the fire water system to provide backup to the Auxiliary Feedwater Pumps.
The target date for completion_of the analysis is December 15~ 1994.
Unresolved Item 50-255/94002-01
- The team identified the 1 ack of over-pressure protection for CCW heat exchangers (HX) E-54A and E-548.
The concern *i nvo 1 ved over-pressure due to thermal expansion stemming from service water valve isolation. Palisades's ASHE Code of record required each vessel to be protected from any conditians specified in the certified design specification.
The code further required to document the degree of over.:pressure protection in a summary technical report.
The licensee was unable to retrieve the summary technical report that justified the lack.of over-pressure protection prior to completion of the inspection.
The licensee committed to locate the report or perform the
- technical analysis to show Code compliance.
CPCo Response
~we h*ve requested the original plant architectural engineer to complete a final search for the code-related documentation for the CCW heat exchangers by May 6, 1994.
If the search is successful~ we will review the documentation for acceptability.
If this search is unsuccessful, a summary technical report documenting whether over-pressure protection is needed will be completed~ The issue of documentation for the over pressure protection of the CCW heat exchanger will be completed by June 15, 1994.
Unresolved Item 50-255/94002-02 r
The results of tests, ca7Cu7ations and engineering evaluations were inconclusive and could not be used to determine if the SWS would fu1fi17 its safety related function at elevated Jake water temperatures combined.with other adverse design basis conditions.
2 The licensee conc7uded that the SW and CCW systems were currently operable because current 7 ake water temp.eratures were 7 ess than 50"F.
This temperature provided significant margin to account for a77 issues impacting the SW operability margin.
The licensee committed to resolve the following issues, documented in DR D-PAL-93-272, by mid April 1994.
A.
Neither test results or design basis calculations accounted for
- instrument uncertainties.
- 8.
The analyses that develop required flow. rates to HXs served by* the SWS used only the original design fouling.
No calculations had been performed to eva 1 uate degraded HX performance resu]ti ng from f ou 1 ing beyond the original design value.
- c.
D.
The most limiting system lineup may not have been teste.d.
The impact of increased sw*temperatures and reduced SW f7ow rates on the SW and CCW design pressures and tempera.tures and systenis' operation was not.evaluated.
E.
The root cause of declining flow rates to control room chi77ers VX-10 and VX-11 had not been determined.
F.
As discussed in Section 8.1, the SW pump.IST reference values and pump degradation was not coupled to the required system p~rformance.
G.
The elevated lake water temperature was. not incorporated into the maximum allowable SW system degradation.
. Pending the licensee's completion of a77 the actions impacting SWS margin documented in DR D-PAL-93-272 and review by the NRC, this is considered an unresolved item (50-255194002-02).
CPCo Response We have made an operability determination, as documented in D-PAL-93-272, which concludes that plant operation up to 50°F lake temperature is acceptable. A ~eview of historical plant records show that the temperature of Lake Michigan begins to approach a.nominal temperature of 50°F during the first part of May.
The lake temperature limft of SO"F is being tracked on the plant Limiting Condition for Operations (LCO} control board in the shift supervisors office which tracks conditions which effect plant operability.
As the evaluations listed below progress and issues and uncertainties are better understood, the operability determination may be revised. Such operability determinations will be documented in an engineering analysis and subjected to appropriate technical reviews.
As a result, the target completion dates to attain a
- maximum SWS inlet temperature may be changed accordingly.
3 A.
Action will be taken to account for instrument uncertainties associated with the SWS and-CCW testing in an overall reanalysis* of the syste_ms through coirective action D-PAL-93-272.
The target date for completiori of the act.io~ *is May 8, 1994.
?.
An additional action to evaluate the link between analysis inputs and assumptions used in testing practices will also be completed under corrective action D-PAL-93-272 and is targeted for completion by August 1, 1994.
B.
An evaluation of ~ppropriate fouling fatt~r assu~ptions made in heat exchanger performance calculations will be completed.
The evaluation will determine appropriate fouling factors based on Tubular Exchanger
- Manufacturers As_soci at ion (TEMA} recommendat i ans for existing service conditions, plus a review of existing maintenance and testing practices to determine where degraded fouling assumptions may be appropriate.
The target date for completion of the corrective action is May 8, 1994.
C.
An ev~luation to assure that the most limiting syste~ hydraulic lineup is considered in our analysis will* be conducted under D-PAL-93-272.
The current date for completion of the corrective action is May 8, 1994..
D.
An analysis to evaluate the impact of the elevated SWS _and CCW temperatures on system design ratings and performance will be completed as corrective actions under D-PAL-93-272.
The target date for completion of this corrective action is May 8, 1994.
E.
A corrective action has been initiated under D-PAL-93-272 which requires system engineering to determine and correct the cause of the reduced flow
- to VC-10 and VC-11.
The present plan to accomplish this action includes a boroscope inspection of the subject service water piping to verify the piping is not fouled.
We will also be looking at the instrumentation for accuracy issues and tubing silting problems that may be contributing to.
- this apparent low flow scenario.
Based on these results, actions correcting the deficiencies will be taken.. These actions will be completed during the 1995 refueling outage.
F.
A corrective action has been initiated under D-PAL-93-272 to develop reference values for SWS pump testing (IST} which are related to the design basis and accident analysis.
The corrective action includes
4 rev1s1on as necessary of the appropriate test procedures.
The target date for completion of this corrective action in June 15, 1994.
G.
Reanalysis of the SWS performance will ensure that the appropriate maximum SWS inlet temperatures are evaluated along with the maximum expected system degradation. This analysis will be completed as a corrective
- action under o~PAL-93-272. The target date for completion of the corrective action is May 8, 1994.
Unresolved Item 50-255/94002-03 Corrective actions in response to D-PAL-93-272 wi71 comple{e the development of SWS pump testing reference values and requir~d system performance.
Additiona71y, the licensee intended to review the basis for IST reference values and a77owed degradation for a71 Section XI pump tests to ensure tha.t they were adequately coordinated with safety analysis performance criteria.
This issue is considered an unresolved item pending the licensee's review to determine impact on the IST reference values *and the possible effect on past ESS pump operability.
CPto.Response As noted in response to Unr~sol~ed It~m 50-255/94002-02 Item F,. a corrective action has been initiated under D-PAL-93-272 to develop reference values for SWS pump testing which are related to the design performance.
A correctiv~ action was written under D-PAL-93-272 to develop a basis for reference values for all safety related pumps in the Inservice Test Program which are directly related to the design basis and accident analysis.
The corrective action requires revision, as necessary; of the appropriate test procedures. After the ISI pump reference values are ~etermined, reviews will be completed to determine the affect, if any, on past ESS pump bperability.
. The target date for completion of the corrective action is August 1, 1994.
WEAKNESSES NRC Identified Weakness The NRC inspectors ran several scenarios on the plant simulator.
The first
The SWS critical header A leak,.which was located in the CCW pump room, was not isolated until 30 minutes after the event was identified by the crew.
This created the potential for flooding of the CCW pump room.
Because procedure ONP 6.1, "Loss Of Service Water," Revision 5, did not cont*atn any specific guidance to isolate the leak, operator aid (DA) 136 was
used,to determine which valves should be closed to determine leak location.
OA 136 was a SWS simplified schematic that was attached to the control panel.
Although the crew successfu17y isolated the SWS leak, identified leak location, and determined the impact on plant operation, the team considered the delay to complete leak isolation actions a weakness.
CPCo Response 5.
The simulator.scenario consisted of a service water line leak in the CCW Room on the 'A' Critical Service Water Header.
The crew suspected a service water system leak when the SWS standby pump start~d and critical service water system header pressures dropped significantly. The Shift Supervisor subsequently ordered an ~mergency down power, however during the down power, the plant was tripped due to voltage regulator problems.
While the crew commenced EOP 1.0, "Standard Post Trip Actions," immediate actions a LOCA event was initiated~ Shartly after completing EOP 1.0, the LOCA was.
identified and the crew focused their immediate priorities on the LOCA since the service water critical header pressures remained above the Safety Function St~tus Check Acceptance Cr~teria of 42 psig.
After sufficient action was taken on the LOCA, the crew re-directed their efforts to isolating the SWS leak which was approximately 30 minutes later:. -
- The following actions will be performed to enhance operator*response in identifying SWS leaks:
- 1.
We will enhance ONP 6.1, "Loss of Servic~ Water," to effectively proceduralize a leak isolation process.
However, the procedure will be changed only if we are sure that the probability of misl~ading/misdirecting efficient leak isolation efforts is low.
- 2.
Additional simulator tr~ining will be completed on ONP 6.1, "Loss of Service Water."
NRC Identified Weakness This weakness w~s identified in the licensee's operating procedures~
SOP 16, Steps 5.1.2 and 7.6 prevented initiation* of backup coo-Jing from the SWS to the ESS pumps if norma 1 coo*1 i ng from CCW was 1 ost concurrent with an SI signal. Procedure compliance would prohibit opening the SWS valves to the ESS pumps with the CCW valves open.
The CCW valves would remain open until the SI signal could be reset. Current procedural compliance results in loss of cooling water to the ESS pumps.
The licensee indicated that the procedure would be revised to allow opening the SWS valves to the ESS pumps if the CCW valves were open and an SI signal was present.
A CAUTION preceding step 7.6 would also be added to alert the operator that CCW would drain to Lake Michigan with a resultant loss of CCW
system functions, if SWS coo 1 ing to the ESS pumps was a Ugned with either CCW valve open.
CPCo Response 6
SOP 16, "Component Cooling Water (CCW) System Procedure," Step 7.6 provides an option of supplying service water to the ESS pumps with a loss of CCW cooling supply. This section required closure of the CCW supply and return valves prior to opening the SWS supply and return valves. A precaution, Step 5.1.2, also noted that the CCW supply and return valves shall not be open when the SWS supply and return valves are open since this would allow CCW system water drainage to the lake.
The pre~aution could have been interpreted as ~n *:
environmental issue only.
The procedure also did not ad~quately address the*
case when an SIAS signal was present and the CCW supply and return valves.
could.not be closed.
The fo 11 owing actions wi 11 be performed to correct this procedural weakness:.
- 1.
A caution was added to SOP 16, Section 7.6, identifying the inability to close the CCW supply and return valves with an SIAS si.gnal.
The caution also indicates that if the servi~e water cooling option is performed, the.*
CCW system will drain to the lake and CCW cooling to other plant equipment would be lost. This action is completed.
- 2.
SOP 16, Step,5~L2 was revised to clearly._identify the result* of draining th~ CCW system to the lake. This actibn was completed.
- 3.
SOP 16, Sections 7.6 and Step 5.1.2 will be revised in accordanc'e with the*
engineering resolution for resolving the single failure co~cern. This action will be completed after engineering resolution of the single
- failur~ vulnerability of the CCW system.
NRC Identified Weakness This weakness was identified in the licensee's operating procedures.
SOP 15, "Service Water System," Revision 7, Step 4.1.2 contained a similar statement as described above.
The licensee indicated that this procedure.
would be revised.
CPCo Response The SOP 15, Revision 7, Step 4.1.2, requirement coincides with the requirement of SOP 16, Step 5.1.2..
SOP 15, Step 4.1.2 will be revised in a~cordance with the engineering resolution for resolving the single failure concern.
This action will be completed after the engineering resolution of the single f~ilure vulnerability of the CCW system.
7 NRC Identified Weakness
- This weakness was id~ntifi~d in the licensee's operating procedure~.
- Annunciator Response Procedure (ARP) 7, Window 29, "Service Water Bay 1 ow Level," did not provide guidance regarding what level SW pumps should be tripped if SW bay level was decreasing.
Thfs item was previously identified during the licensee's SSDC conducted in Hay 1990.
The licensee indicated that the procedure would be revised.
CPCo Response ARP 7, Window 29 will be revised tb provide cl~arer directions to operator~
for tripping the service water pumps.
NRC Identified Weakness This weakness was identified in the licensee's operating procedures.
ONP 6.1, Revision 5, Attachment 1, "Alternate Method of Supplying the Intake*
Structure," requited tripping the SW pumps if warm water recirculation pump f P-5) was used to supply water to the intake structure.
This did not coincide
- with SOP-14, "Circulating Water and Chlorination Systems," Revision 16, step 7.13.1, which provided steps to supply the intake structure from P-5 but did.
not require tripping the SW pumps.
The licensee indicated that'guidance for tripping the SW pumps would be incorporated into *the appropriate ARP and removed from ONP 6.1, Attachment 1.
No revisions to SOP 14 were deemed necessary.
CPCo Response ONP 6.1, Revision 5, Attachment 1, was developed on the assumption of a collapsed intake piping or crib.
The result of such a collapse would be an immediate emptying of the intake pump bay, therefore, the procedure ensured that the SWS and dilution water pumps were tripped off.
SOP 14, Step 7.13.1 was developed as a warm water supply to melt ice off the traveling screens, which does not necessarily requir~ tripping of the SWS or dilution water pumps.
The following actions will be performed to correct this procedural weakness:.
- 1.
ONP 6.1 has been revised to require tripping of the dilution water pumps only based on water cohservation for the SWS system.
- 2.
The ARP 7 will be revised to provide direction when the SWS and dilution water pumps should be tripped off.
8 NRC Identified Weakness The team identified non-seismica11y constructed scaffolding, insta11ed in the.
west safeguards room over safety-related equipment.
The licensee performed an engineering analysis, which concluded that the scaffolding did not meet the requirements of procedure HSH-H-43, "Scaffolding,". Revision O, but was not a s~fety concern.
The licensee removed the scaffolding and initiated a revision to HSH-H-43 that provided additional instructions for scaffotding in safety-related areas.
The revision would include walkdown inspections, supervisor sign-off for installation, clarification of requirements, and approval and justification by the system or assigned engineer for deviations from the procedure.
The team considered this action acceptable.
CPCo Response On January 20, 1994, NECO Civil En~ineering performed an analysis for scaffolding and concluded the scaffolding did not me~t the requirements of Procedure MSM-M-43.
However, the scaffolding did not reflect a safety concern.
On January 21, 1994, plant maintenance personnel performed a walkdown and found only one qther scaffold installed in the plant.
The installed scaffold met the installation requirements of procedure MSM-M-43 and there was no safety-related equipment involved.
On January 22, 1994, plant maintenance repair workers dismantled and removed the scaffolding from the.
West Engineering Safegu~rds Room.
As a result of this event the following corrective actidns will be taken:
~
- 1.
Procedure MSM-M-43 will be revised to include (1) instructions for walkdown inspection for scaffolding installed in safety-related areas; (2) a supervisor sign-off for scaffolding installed in safety-related areas; and (3) to clarify requirements (for free-standing, separation
_distances, braced scaffold, etc.) as they relate to requirements for scaffolds installed in safety-related areas~
,\\
- 2.
Responsible maintenance supervisors will be informed of the requirement that any deviations from the Procedure MSM-M-43, with regard to general scaffolding requirements and requirements for scaffolds in safety-related areas, require approval and justification by engineering before the scaffolding can be accepted for use.
- 3. Training will be provided for Plant Maintenance Supervisors on their r~SJ><;msibil ities -~nde.r permanent Maintenance Procedure MSM-M-43.
NRC Identified Weakness The team identified that a ground strap was not connected on an recently replace containment spray pump motor.
DR D-PAL-94-017, evaluated the problem
. and co.ncluded that the work package instruction lacked the detail necessary to ensure the ground strap connection.
The package also contained other minor ;
discrepancies as we17.
The.licensee connect~d the ground strap and was
- developing corrective actions for the other minor deficiencies.
The team*
considered this attion acceptable.
CPCo Resoonse 9
The root cause of the condition (unconnected ground strap) described on Deviation Report (DR) D-PAL-94-017 can be attributed to an inadequate job plan on Work Order (WO) 24202957.
This WO plan did not contain sufficient detail to ensure that the work would be ~one properly. A procedure exists (ESS-E-36) that contains detailed steps concerning the re-connection of the ground strap on the motor, EMA-1114.
While.there is no requirement to use this procedure for the replacement of the motor, the WO plan should c6ntain an equivalent amount of detail.
While reviewing the WO package and related documentation, the following discrepancies were also noted and corrective actions will be assigned to" address them as well.
- 1.
The WO plan called for motor removal, ~hipmeMt for refurbishment, and.
reinstallation of same motor.
The spare motor from stock was used du~ to problems d~ring refurbishment of the ~emoved motor and the WO plan was not.
revised to reflect the subtle differences between the spare motor and the one that had been removed from the pump.
- 2.
The Work Instruction (WI) WI-SPS-E-02 data sheet was not pro~erly filled out, in that the motor serial number was not listed as required.
- 3.
Procedures ESS-E-36 and MSE-E-5 requir~ the procedure and all* attachments to be filed in DCC (i.~., filmed).
The WO package was purged of these
~heets prior to closeout and therefore this requirement was not met.
4.' Several entries on the WO summary as well as a *signature in FHS-M:.23 did not contain dates.
I
- 5.
The WO package did not contain the issue ticket for the Raychem cable splices used during the reconnection of the motor.*
- 6.
The equipment database has not been revised to reflect the serial number of spare motor that was installed.
. ]. The radiation hot work permit does not provide a box to be checked that
~overs the use of a torch for heating.
- 8.
Torquing of the motor hold down bolts was signed as performed on July 10, 1993 and verified on July 11*, 1993. This activity was in fact performed on July 11, 1993.
- 9.
- Step 9 of the WO plan contained a double verification that the WO summary shows was performed on July 8, 1993 but was signed July 19, 1993.
10 Corrective Actions
- 1.
The evaluation of this investigation (D-PAL-94-017) and its associated WO will be reviewed with members of the maintenance department specifically addressing items 1, 2, 4, 5, 8, and 9 listed above.
- 2.
The practice and control used to revise the database when a spare motor is installed will be evaluated to determine if current practice is acceptable or if the method should be modified to ensure timely database update.
- 3.
An assessment will be completed to revi~w the need to revise. the hot wbrk permit form to include a box to be checked to address heating with a torch.
- 4.
All'permanent maintenance procedures will be reviewed to determine which
.ones r~q~i~e the filming of all attachments.
Those permanent maintenance procedures whose filming requirements need to be clarified, will be revised following th~ review.
NRC Identified Weakness The team found that the licensee had not fully evaluated the susceptibility of SWS instrument line fouling.
Specific flushing requirements had only been implemented for instruments that had been clogged in the past; however, walkdowns of SWS pump discharge lines found that instrument lines to pressure switches for standby pump starting had long stagnant.horizontal runs that might be subject to fouling.
These lines were.not checked by periodic maintenance or surveillance. Also omitted were stagnant 11nes to and from the former control room air conditioners.
This was not consistent with the GL intent, which reconunended licensees establish routine maintenance of. SWS piping and components to ensure that silting and bio-fouling could not degrade system performance.' The licensee conunitted to review the.maintenance of these and other instrument lines.
CPCo Response It is apparent that the original Generic Letter 89-13 effort did not address all instrument lines. During the Palisades SWOPI inspection the NRC Information Notice 94-003 was issued. The Information Notice entitled, "Deficiencies Identified During *service Water System Operational Inspections,"-----,--
notifies licensees of concerns regarding instrument tubing becoming fouled with silt and. acknowledges that this issue should have been better addressed by the Generic Letter 89-13 implementation.
We will review the specific issues in the Information Notice to see how those issues apply to Palisades,
11 and incorporate actions as need&d in our preventative maintenance program to ensure that tubing doesn't become fouled.
The review of the Information Notice and any corrective a~tions needed will be completed by the end of the 1995 refueling outage.
An AIR, A-PAL-94-009, w~~ initiated to assure that the
-issue of the stagnant lines to and from the former control room air conditioners is addressed under the Generic Letter and Information Notice 94:004 guidelines.