IR 05000245/1988003
| ML20151G533 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 04/07/1988 |
| From: | Mccabe E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20151G526 | List: |
| References | |
| 50-245-88-03, 50-245-88-3, NUDOCS 8804200033 | |
| Download: ML20151G533 (11) | |
Text
_ _ _ _ _ _ _ _ _ _ _ _
.
.
.
.
U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Report:
50-245/88-03 Docket No:
50-245 License No:
OPR-21 Licensee:
Northeast Nuclear Energy Company Facility:
Millstone Nuclear Power Station, Waterford, Connecticut Inspection at: Millstone Unit 1
Dates:
February 9, 1988 through March 21, 1988 j
Inspectors:
William Raymond, Senior Resident Inspector l
l Lynn Kolonauski, Resident Inspector Reporting i
Inspector:
Lynn Kolonauski j)&
7!87 Approved:
M e
E. C. McCab, Cnief, Reactor Projects Section IB Date Summary:
Inspection from 2f,9L88 - 3/21/88 (Report No. 50-245/88-03)
l l
Scope.
Routine NRC resident inspection (119 hours0.00138 days <br />0.0331 hours <br />1.967593e-4 weeks <br />4.52795e-5 months <br />) 01' plant operations, physical security, the reactor scram on March 12, surveillance, maintenance, unlocked high l
radiation area doors, the potential inaccuracy of the containment high range radi-ation monitors, licensee event reports and ccamittee activities.
Results.
The inspection identifiea no unsafe plant conditions.
Further licensee
'
and/or inspector followup is warranted on: (i) timely implemantation of Technical Specification amendments (Section 6.2), and (ii) control of locked high radiation i
I areas (Section 9.0).
,
l l
l l
l
!
8804200033 G80411 PDR ADOCK 05000245 o
__
i
.
.
.
TABLE OF CONTENTS
,
Page
1.0 Persons Contacted....................................................
2.0 Summary of Facility Activities.......................................
3.0 Status of Previous Inspection Findings..
............................
3.1 VIO 87-33-01: Reportability of ADS Check Valve Failures.........
4.0 Facility Tours and Operational Status Reviews........................
H 4.1 Safety System Operability.......................
...............
4.2 Plant incident Reports..............
...................
......
5.0 Plant Security.
................................................
5.1 Security Sergeants Arrested Offsite for Cocaine Possession......
5.2 Partial Failure of the Security System Computer........
.......
6.0 Reactor Trip on Low Water Level......................................
j 6.1 Fail ure in the Reactor Water Level Control System...............
6.2 Technical Specification 3.6.B.3.........
......................
l 7.0 Surveillance....
....
..........................................
i 8.0 Maintenance..................................................
.......
9.0 High Radiation Area Doors Found Unlocked..................
..........
10.0 Datential Inaccuracy of Containment High Range Radiation Monitors....
11.0 Licensee Event Reports..............................................
12.0 Onsite Plant Operations Review Committee.
.........................
13.0 Management Meetings...
.............................................
.
,
i i
--.
..
. _ _,., - - _ - - _
-
.
.
.
DETAILS 1.0 Persons Contacted Mr. S. Scace, Station Superintendent
Mr. J. Stetz, Unit 1 Superintendent Mr. W. Vogel, Engineering Supervisor
'
Mr. M. Bigiarelli, Assistant Engineering Supervisor Mr. J. Quinn, Assistant Engineering Supervisor i
Mr. M. Brennan, Health Physics Supervisor i
Mr. P. Przekop, Instrumentation and Controls Supervisor Mr. J. Barnett, Licensing
'
Mr. R. Crandall, Supervisor. Radiological Engineering Ms. P. Weekley, Security Supervisor The inspector also contacted other members of the Operations, Radiation Pro-tection, Instrumentation and Control, Maintenance, Engineering, and Security Departments.
2.0 Summary of Facility Activities Millstone 1 operated at full power for most of the inspection period.
On February 17 and March 3, power was reduced for routine surveillance and cor-rective maintenance, which included steam leak repairs in the heater bay.
On March 12, the unit scrammed on low reactor water level due to a spurious feed pump trip and a subsequent failure in the Reactor Water Level Control System (See Section 6.0).
The unit was returned to full power on March 14.
Full power operation continued through the remainder of the inspection period.
3.0 Status of Previous Inspection Findings (92702)
3.1 (0 pen) VIO 87-33-01: Reportability of ADS Check Valve Failures
{
On March 7, 1988, the licensee notified the inspector that additional time was needed to review the issues and respond to this violation, which had a response due date of March 16, 1988.
The licensee basis included the need to review the differences between the NRC and NNECO on the re-portability requirements of 10 CFR 50.72 (b)(2)(iii).
The NRC concluded that there was sufficient cause to extend the response time to allow further discussion to better understand the reporting requirements.
The licensee committed to respond to the violation by April 15, 1988.
4.0 Facility Tours and Operational Status Reviews (71707)
Control room instrumentation was inspected for correlation between channels, proper functioning, and conformance with Technical Specifications (TSs).
Alarm conditions in effect and alarms received were reviewed and discussed with the operators. Operator awareness and response to off-normal conditions was reviewed; operators were found to be cognizant of plant conditions and indications. Operating logs and Diant Incident Reports (PIRs) were reviewed
.
.
for accuracy and adherence to station procedures.
Posting, control, and the use of personnel monitoring devices for radiation, contamination, and high radiation areas were inspected.
Plant housekeeping controls were observed, including control of flammable and other hazardous materials.
Inspections of the control room were conducted on backshifts on March 3 at 8:00 p.m.,
on March 12 at 10:30 a.m., and on March 13 at 10:00 a.m.
All shift personnel were found to be alert and attentive to their duties.
No unacceptable condi-tions were identified.
The following activities were also addressed.
4.1 Safety System Operability Standby emergency systems were reviewed to determine system operability and readiness for automatic initiation.
The following systems were in-cluded: low pressure coolant injection, core spray, feedwater coolant injection, and standby gas treatment.
The status of the isolation con-denser, control rod drive hydraulic control units, and the emergency diesel generator was also inspected.
NRC review considered proper posi-tioning of major flow path valves, operable normal and emergency power supplies, proper operation of indicators and controls, and visual in-spections for proper lubrication, cooling, and other conditions.
Refer-ences used for the review included the Updated Final Safety Analysis Report, flow diagrams, and operating procedures.
No inadequacies were identified.
4.2 Plant Incident Reports Selected Plant Incident Reports (PIRs) were reviewed to (i) determine the significance of the events, (ii) review the licensee's evaluation of thc events, (iii) review the licensee's response and corrective ac-tions, and (iv) verify whether the licensee reported the events as re-quired.
No inadequacies were identified.
The following PIRs were re-viewed: 1-88-14 and 1-88-15 (see Section 5.0), and 1-88-10 (see Section 9.0).
5.0 StationSecurity(81064]
During station tours, the inspectors verified proper implementation of selected aspects of the station security program.
These included site access controls, personnel searches, adequacy of physical barriers, teporting of security
{
events, compensatory measures, ano guard force response to alarms and degraded conditions.
Safeguards Event Reports (SERs) 88-01 through 88-03 \\;ere reviewed.
No inadequacies were identified.
The following events warranted further in-spector followup.
5.1 Security Sergeants Arrested Offsite for Cocaine Possession On February 8, the Security Supervisor notified the inspector that two security sergeants, under contract with Burnes, were arrested off site for cocaine possession.
The licensee promptly terminated site access badges for both individuals. One contractor resigned; the other was
-
. --_ ______
-
i
terminated.
Licensee investiaation of the incident included a review of previous drug testing results; both individuals had negative test results on record.
It is notable, however, that a recent sample for one of the two had a broken custody chain which required that a new sample be taken. The retest was not rescheduled prior to the individual's ter-mination.
The inspector had no further questions.
5.2 Partial Failure of the Security System Computer On February 10, the inspector was informed, via the Emergency Notifica-tion System (ENS), that the licensee had discovered that a partial fail-
'
ure of the security system computer had resulted in the loss of alarm capabilities at the Central Alarm Station (CAS).
The computer malfunc-tion, which occurred twenty minutes prior to its discovery, affected the security alarms for Units 1 and 2.
Unit 3 security alarms were unaf-fected. Access controls for for the Protected Area (PA) and Vital Areas (VA) remained in effect throughout the failure.
Appropriate measures were instituted as compensation for the computer malfunction.
The com-
'
puter was restored to full operability within minutes of the discovery.
The licensee made a one hour report (in accordance with 10 CFR 73.71c)
to the NRC Emergency Operations Center.
The licensee subsequently with-drew the report after discussion with an NRC safaguards specialist, who indicated that a safeguards event log entry would satisfy the reporting requirements because compensatory measures were implemented within ten minutes.
The inspector had no further questions.
6.0 Reactor T-ip on Low Water Level (93702)
At 5:18 am on Saturday, March 12, during ncrmal full power operations with the "A" and "C" Reactor Feed Pumps (RFPs) running, the "A" RFP unexpectedly tripped.
No prior alarms were observed by the operaturs; this observation was confirmed by inspector review of the alarm printout. The first indication of the "A" RFP trip was the change in the motor breaker status lights from
'
red to green. This was observed by the Supervising Control Operator (SCO),
who immediately started the "B" RFP. Although reactor water Icvel had then dropped only three inches below the normal operating level (30" to 27"), a reactor scram on low water level (20") was not avoided.
Reactor water level continued to drop, causing automatic initiation of the Standby Gas Treatment System (SBGT) at -8", and reaching a low of -13".
(At Millstone 1, the low-low setpoint is -48".)
The operators restorc.d water level to the normal operating band, closed the FW blocking valves upstream of the FRVs, and main-tained water level using the low flow startup valve.
Except for the Reactor Level Control System (see Detail 6.1), all plant equipment functioned as de-signed in response to the plant scram.
ddGT was the only safety system (in addition to the Reactor Protection System) to automatically initiate.
The inspector reviewed the alarm and plant parameter printouts and found no dis-crepancies.
The operators entered and executed OP-502, "Emergency Plant Shutdown." Through review of the alarm printer output, the irspector verified the accomplishment of several steps in the procedure.
-
-
.
.
.
'
The licensee documented the event in Plant incident Report (PIR) 1-88-14, and made an immediate notification to the NRC in accordance with 10 CFR 50.72 (b)(2)(ii).
Die inspector verified the accuracy of the PIR and the. scram report through discussions with plant staff and by review of the transient data and found no inconsistencies.
6.1 Failure in the Reactor Water Level Control System The plant alarm computer printout showed that the "FW PMP A SUCT PRESS LO" alarm came in shortly after the pump had tripped.
As documented in PIR 1-88-15, licensee testing for the feed pump suction pressure-switches (PSs) determined that the PS for the "A" pump was inoperative and that the PS for the "B" pump was out of tolerance.
The PSs were i
replaced and r9 calibrated, respectively.
No alarms or relay drops were present at the "A" RFP cabinet. A security guard posted in the area of the "A" RFP cabinet observed no personnel or abnormalities near the "A" RFP cabinet.
The "A" RFP motor breaker was extensively tested by the Production Test and Maintenance Departments.
No direct cause of the breaker trip was identified.
Nonetheless, the breaker was replaced.
The licensee was unable to determine the cause of the RFP trip.
'
It was originally thought that the RFP trip was the sole cause of the cecrease in reactor water level.
However, licensee review of the transi-ent traces produced by the process computer revealed that level restora-tion should have been successful because the "B" RFP pump was started within two seconds of the "A" RFP trip and after level had dropped only three inches.
The traces showed that, in spite of the start of the "B" RFP, both reactor water level and FW flow continued to drop at the rate initiated by the "A" RFP trip.
Further review indicated that the Feed-water Regulating Valves (FRVs) had closed when the "A" RFP tripped.
Extensive licensee investigation determined the cause of the FRV closure to be dirty contacts for Relay 111, located within the reactor water level control system.
The fe?dwater pumps at Millstone 1 are protected from runout conditions by runout flow control circuitry. At 105% flow for the running pump combination, the control circuitry removes the nor-mal level control signal from the FRVs and inserts a signal from a sepa-rate flow controller.
Relay 111 inputs the number of running feed pumps to the RFP ronout flow control setpoint.
Prior to the RFP trip, water level was in single element automatic control.
Level control shifted, as designed, to flow controller control as designed when the RFP tripped.
.o Total feed flow reached 105% for the running pump combination, which at the time was one RFP
"B",
The dirty contacts in Relay 111 caused the flow control setpoint to go to zero.
In response, the control system closed the FRVs in ar attempt to match total FW flow with the demand from the flow control setpoint. As corrective action, the relay contacts were burnished.
Thereactor water level control system then tested satisfac-toril '
.
.
The licensee is considering additional corrective actions to prevent re-currence of this problem for the feedwater flow control circuit and other safety-related control circuits that may be susceptible to the same failure.
Control circuits with components in a passive state during routine operations will be specifically considered.
Actions being con-sidered include o d uically burnishing contacts, additional testing to ttect th i>uilding of contact resistance, and replacement of HGA relays wito a type more suitable to the controls circuit application.
There are no immediate plans to increase the frequency of relay preventive maintenance, and the actions decided on will be taken during the next refueling shutdown.
The licensee stated that long term corrective action plans will be finalized as part of the formal review process for~the plant information report and will be included in the licensee event re-port to be submitted to the NRC for the reactor scram.
The inspector reviewed the licensee's plans and schedule and identified no inadequacies.
6.2 Technical Specificction 3.6. M With the reactor water level control system restored, startup began at 12:23 am on Sunday, March 13.
Criticality was achieved at 5:18 an.
Startup was halted and the reactor was made subcritical because the lic-ensee was unable to comply with the implementing procedure for TS 3.6.B.3,
"Primary System Boundary, Core Criticality." This TS requires that "the reactor vessel shell and fluid temperatures measured at the vessel shell adjacent to the shell flange, at the vessel bottom head, at the bottom head drain, and fluid temperatures measured in recirculation loops A and B shall be at or to the right of the curve shown in Figure 3.6.3."
An August 1987 TS Amendment 9 had added the "bottom head drain" to the parameter listing.
In the approved implementing procedure, that tempera-ture is measured by a thermocouple (T/C) on the Reactor Water Cleanup (RWCU) botto'n head drain line, located about 30 feet from the vessel.
The licensee concluded that this T/C was not the appropriate monitor point and that the function is nonetheless accomplished because the ves-sel bottom head is me.nitored by another T/C.
The licensee rrotified the inspector, who referred the matter to NRR.
The licensee presented their position to the NRR Project Director by phone at 9:00 am on March 13.
The Project Director agreed that the T/C on the vessel bottom would satisfy the need.
The licensee then held a PORC meeting which was at-tended by the inspector. After further licensee discussion with NRR on March 14, it was agreed that the "bottom head drain" parameter would be removed from the TS through a normal TS amendment.
The licensee resumed startup at 10:00 am on March 13; criticality was achieved at 12:10 pm.
The inspector verified completion of the pre-critical check list and observed portions of the startup, including the approach to and attain-ment of criticality.
The generoic was placed on line at 7:40 pm; full power was achieved at 11:20 pm on Marcn 14.
The inspector reviewed the hi: tory of the Augnt 1987 amendment to TS 3.6.3.B to assess its applicability and licensee compliance during prior startups. With August 20, 1987 (the date of issuance) taken as the ef-
,
.
.
fective date of Amendment 9, the amendment applied to three startups in addition to the March 13 one.
On August 26, the reactor was restarted after tripping during surveillance testing for the Average Power Range Monitors. On September 4, the reactor was restarted after tripping on September 3 due to low scram air header pressure.
The reactor was also restarted on November 16, af ter a shutdown was conducted to investigate and repair IC-1 inside the drywell.
The inspector reviewed the strip charts for the parameters required to be monitored by TS 3.6.8.3 for the November 16 startup and found the licensee to be compliance with the TS amendment. A contributing factor in attaining RWCV drain line temperatures that complied with TS 3.6.B.3 was that the reactor was in a cold shutdown condition for the November 16 startup, as opposed to starting up from hot shutdown on March 13.
It appears that, when the plant is started from a cold condition, the associated temperatures increase together and compliance with the imple-menting procedure for TS 3.6.3.B is possible, as was verified by inspec-tor review of the recorder traces for the November 16 startup.
The inspector did not verify the licensee's compliance with implementing procedures for the September 4 startup because the reactor was restarted from a cold condition and noncompliance was unlikely for the reasons described above. The inspector also did not verify compliance for the August 26 startup because, although the amendment was issued or, August 20, the licensee did not receive it until September 2.
The inspectors identified a concern involving the timeliness in imple-menting the TS amendment 41though the TS was issued by the NRC with an effective date of August 20, 1987 and tbn licensee received the amendment on September 2, the licensee did not file the amendment in the control roo:n until October 1 and did not revise the associated procedures until Octcber 26 and 30.
In this case, no safety effect resulted from the delay. However, there are potential safety consequences if amendments are not promptly implemented. More effective communication between the licensee and the NRC during the amendment process and better licensee preplanning would allow the licensee to fully implement TS amendments as they become effective.
This consideration will be reviewed further during routine inspection.
In observing the licensee's action in returning the unit to operation, the inspector noted an organized approach to resolutie1 of the problems encountered prior to and during startup.
Support groups performed in
,
a well ccordinated manner to resolve t'ie equipment failures. The in-
'
spector also noted that a sufficient level of management presence at the j
site, including the plant manager and first line supervisors.
,
-
-
_.
.
_ -, -,,.-- -_ _ _-.
_ _ - - - -.
- _,-.
_..
.
.
.
7.0 Surveillance (61726)
On March 1, the inspector observed parts of the following surveillance tests for conduct in accordance with approved procedures, for test result compliance with technical specification and administrative. requirements, and for deft-ciency correction in accordance with administrative requirements.
SP408H, "Drywell High Pressure Scram and Containment Isolatien Functional
--
Test," conducted by the Instrumentation and Controls Department.
SP661.4, "Standby Liquid Control Pump Operational Readiness Test," con-
--
ducted by the Operations Department.
For both surveillances, the inspector verified that the proper approvals and tagouts were obtained prior to the test start.
The inspector observed effec-tive communications between the test team members and the control room, the presence of adequate supervision, and careful and deliberate actions by test-ing personnel.
The inspector observed extensive use of independent verifica-tion in returning the systems to their normal standby condition upon comple-
,
I tion. No unacceptable conditions were observed.
8.0 Maintenance (62703)
On March 8, the inspector observed parts of the maintenance conducted on the
"C" Service Water (SW) pump, which had been removed from service to replace the pump bearings and investigate the high vibration detected during routine preventive maintenance.
The inspector observed the pump shaft, impeller, and bearings, and found no indication of excessive wear. The inspector verified that the work order package was at the job site as required by Administrative Control Procedure (ACP) QA-2.02C, "Work Orders," and that the required au-thorizations and tagouts had been obtair.ed prior to the start of the job.
The inspector observed the use of approved procedures and sufficient manage-ment presence at the job site.
The inspector verified that the control room operators were aware of the mrIntenance and of the unavailability of the SW pump.
The appropriate Limit-ondition of Operation (LCO), TS 3.5.C,3 (Feedwater Coolant Injection),
i was entered when the pump was removed from service, and was exited when the pump retested satisfactorily. No inadequacies were identified.
9.0 High Radiation Area Doors Found Unlocked (92703)
The inspector reviewed PIR 1-88-10 which describes the February 22 discovery of an unlocked high radiation area (HRA) door.
Since September 1987, five separate discoveries of unlocked HRA doors have occurred at Millstone 1.
The four previous events were addressed in NRC inspection reports (irs) 50-245/
87-27 and 50-245/88-02.
The inspector verified that Health Physics (HP) pro-cedure, H951, "High Radiation Key Control," requires HP technicians to ensure that the individual receiving an HRA key is aware of his responsibility to maintain the key and the area. A contributing factor noted in IR 50-245/88-02
'
._
..
.. -. -- -,-. - - - - -
-. - -... -
..
,
_ _ _ _ _ _ _ _ _ _ _ _ _
.
.
.
was that the HRA door can appear closed, but not actually be locked.
This was not applicable in the February 22 discovery, as the door was actually propped open, which is in violation of H951.
The inspector verified that signs stating HRA restrictions were posted on the HRA doors found unlocked.
These incidents indicate possible poor worker attitude and weakness in licen-see provided training on HRA access controls. While no personnel overexpo-sures resulted, the unlocked HRAs increase the potential for unplanned and/or unnecessary radiation exposures.
The failure of the licensee's previous cor-
{
rective actions to prevent recurrence of this problem is a potential enforce-ment issue that will be addressed during further inspection (UNR 50-245/86-03-01).
10.0PotentialInaccuracyofContainmentHighRangeRadiationMonitors(921011 During a loss of Coolant Accident (LOCA), high containment temperatures could cause the in containment High Range Radiation Monitors (HRRMs), installed pursuant to the TMI Action Plan, to indicate less than the actual radiation level.
The potential inaccuracy of the HRRMs was previously addressed in IR 50-245/88-02, Section 11.0.
Additional licensee action to resolve this issue includes the establishment of an alternate monitoring method.
The inspector attended the Plant Operations Review Committee (PORC) meetings where the as-sociated Plant Design Change Record (PDCR) was reviewed. An area radiation monitor (RM-12) was relocated to the Control Rod Drive removal penetration and was converted to an HRRM through a range change, While the alternate monitor is now available, the licensee has not yet prepared procedures or conducted training on its use.
Other inspector concerns are discussed in IR 88-02. One is that the HRRMs are used in both the Emergency Plan Implementing Procedures (EPIPs) and in declaring Emergency Action Levels (EAls).
Both must be modified to include the alternate HRRM method.
Also, the TMI Action Plan specifies that Technical Specifications be established to address the operability of the HRRMs, but the licensee has not yet submitted an proposed amendment to the NRC.
The inspector will continue to follow the licensee's progress in resolving the requirements of the TMI Action Plan associated with the HRRMs.
This issue remains unresolved (UNR 50-245/88-03-02).
11.0 Licensee Event Reports (92700)
One Licensee Event Report (LER) submitted during the report period was re-viewed to assess LER accuracy, corrective action adequacy, compliance with 10 CFR 50.73 reporting requirements, and whether there were generic implica-tions or if further information was required.
The LER reviewed was:
83-01, Inadvertent Discharge of Unsampled Floor Drain Sample Tank (FOST) "B".
While preparing the "A" FDST for discharge, an operator inadvertently opened the discharge valve for the "B" FDST.
The resultant discharge was automatic-ally terminated after five minutes when the effluent radiation monitor tripped l
_ _ _ - ___ -
.
.
.-
.
.
on high radiation, causing the common discharge valve to close.
The total activity and radionuclide concentration released were below those allowed by 10 CFR 20 Appendix B.
The LER accura 6ely f? scribed the event with a sufficient level of detail.
IR 50-245/88-02 coverec the event and the lin: :?e's corrective actions.
No inadequacies were noted.
The inspector will review the remaining corrective actions, which include the installation of a common selector switch for the FDST discharge valves.
12.0 Onsite Plant Ope ations Review Committee (40700)
The inspector attended Plant Operations Review Committee (PORC) meetings on February 9, 11, 17.. and 24 and on March ?. 13, and 18.
Technical Specifica-tion 6.5 requirements for committee quorum were met.
The meeting agenda in-ciuded reviews of Plant Design Change Records (PDCRs), procedure revisions, interim changes to procedures, and Plant Incident Reports (PIRs).
Staff engineers made several technical presentations to allow more informed deci-sions by the committee.
The inspector noted active participation by each member and thorough attention to the safety importance for the matters under review. No inadequacies were identified.
13.0 Management Meetings At periodic intervals during this inspection, meetings were held with senior plant management to discuss the findings.
No proprietary information was identified as being in the inspection coverage. No written material was pro-vided to the licensee by the inspector.