IR 05000361/1997025
| ML20198A930 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 12/30/1997 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML20198A904 | List: |
| References | |
| 50-361-97-25, 50-362-97-25, NUDOCS 9801060137 | |
| Download: ML20198A930 (19) | |
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ENCLOSURE 2 U.S. NUCLEAR REGULATORY COMMISSION
REGION IV
Docket Nos.: 50 361 50-362 License Nos.: NPF-10 NPF-15 Report No.: 50-361/97-25 50 362/97 25 Licensee: Southern California Edison C Facihty: San Onofre Nuclear Generating Station, Units 2 and 3 Location: 5000 S. Pacific Coast Hw San Clemente, California ,
Dates: November 9 through December 20,1997 Inspectors: J. A. Sloan, Senior Resident inspector J. J. Russell, Resident inspector J. G. Kramer, Resident inspector Approved By: Dennis F. Kirsch, Chief, Branch F Division of Reactor Projects ATTACHMENT: Supplemental Information
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l-2- 1 EXECUTIVE SUMMARY San Onofre Nuclear Generating Station, Units 2 and 3 ;
NRC Inspection Report 50 361/97 25; 50 362/97-25 l This routine, announced inspection included aspects of licensee operations, maintenance, engineering, and plant support. This report covers a 6 week period of resident inspectio Doerations
- Operations were generally characterized by conservative decisions and action Operatiorn management and supervisors were frequently observed in the control room providing direct oversight of operational activities. Operators were attentive to their indicatioas. Communications among operators were generally complete and specific. A nucler.r plant equipment operator (nonlicensed operator) was observed performing routino rounds in a thorough and attentive manner (Section 01.1)
Operations equipmen; control personnel and the operating crew failed to recognize an applicable Technical Specification (TS) limiting condition for operation (LCO) action statement that should have been entered, until brought to their attention by the inspectors. No LCO action times were exceeded; however, this failure demonstrated a weaknecs in attention to detail while assessing LCO actions for equipment configuratio A noncited violation was identified for failing to create sufficient recocds, either in the operating logs or by separate LCO tracking sheets, to indicate that the action was entered late (Section 04.1).
Malatenante
Electrical technicians demonstrated excellent skill of the craft while replacing an emergency diesel generator (EDG) governor trip solenoid. The maintenance order (MO) used to perform the task was not sufficiently prescriptive because the EDG engine governor to be worked was not stipulated; however, this oversight was compensated for by alert technicians (Section M1.3).
Material condition throughout the units was very good, with some minor deficiencies identified by the inspectc7. The licenseo promptly initiated corrective action for the identified deficiencies (Section M2.1).
Maintenance and surveillance activities were generally performed thoroughly, with work packages in active use. by knowledgeable technicians, and frequently observed by supervision and system engineers (Sections M1.1 and M1.2). However, a noncited violation was identified in one out of six maintenance observations, the licensee failed to provide adequate instructions to licensee Maintenance personnel. The MC instructions did not provide adequate cautions, and the workers' foreman made a judgmental error and provided the wrong instructions to the workers, resulting in a boric acid makeup
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3-(BAMU) pump becoming degraded by touch up painting causing a plugged vent. The corrective actions were thorough and comprehensive (Section M3.1).
Enaineerina
- A documentation weakness was identified by the inspectors associated with the number of pressurizer heaters require for plant operation. Nuclear Design Engineering's ongoing assessment of the minimum number of operable pressurizer heaters to support plant operations was timely. However, the communication of the preliminary results to Operations was informal, and between November 6 and December 4,1997, the analysis of record did not support operation with the number of heaters that were in servic Operations management had provided appropriate guidance to the operators, based on the preliminary results of Engineering's ongoing assessment. At all times, TS requirements were satisfied (Section E2.1).
An operability assessment of a degraded BAMU pump was not thorough, in that it did not assess the operability of the pump in the degraded condition (Section E4.1).
A thorough and probing root cause analysis of the failure of Kerotest 2-inch charging system check valves was performed. A violation was identified because adequcte testing was not performed on the Units 2 and 3 charging line to Loop 1A check valves, in that a design small break loss of coolant accident (SBLOCA) system flow requirement was not verified. This resulted in both Units 2 and 3 operating in an unanalyzed condition for some period of time. An analysis was under review by the NRC Office of Nuclear Reactor Regulation (NRR) that concluded that charging flow was not required for loss of coolant accioent (LOCA) mitigation (Section E8.1).
A noncited violation was identified for failing to implement an adequate charging pump surveillance procedure that tested all contacts in the start circuitry. The licensee had previously reviewed this procedure in response to NRC Generic Letter 96-01, but had failed to identify the inadequacy, demonstrating less than thorough evaluation by Nuclear Engineenng Design in conducting the review (Section E8.3).
Plart Sumo 11 e A medical emergency drill critique was found to be self critical in the identification of performance issues and provided valuable training for emergency response personnel (Section P5.1).
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Report Detalla l
Summary of Plant Status I Both units operated at essentially 100 percent reactor power during this inspection perio i
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01 Conduct of Operations !
01,1 General Comments (71707)
Operations were generally characterized by conservative decisions and action .
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Operations management and supervisors were frequently observed in the control room ' '
providing direct oversight of operational activities. Operators were attentive to their indications. Communications among operators were generally completa and specific! A -
nuclear plant equipment operator (nonlicensed operator) was observed performing routine rounds in a thorough and attentive menne !
04 Operator Knowledge and Performance ;
04.1 TS LCO Action Entry - Unit 2 Insoection Scope (71707)
On December 2,1997, Ine inspectors walked down the Urit 2 main control boards to assess the status and configuration of plant systems and component '
. Observations and Findinas
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l The inspectors observed that both localindications of EDG frequency were not cperable; however, the operating crew had not entered the applicable TS LCO action statement. TS 3.3.12, " Remote Shutdown System," requires that one channel per unit of EDG remote shutdown frequency indication be available, if this condition is not met, then a 30-day action is to be entered. Train A EDG 2G002 had been removed from service and declared inoperable at 7:44 a.m. on December 2,1997 rendering
' EDG 2G002 local frequency indication inoperable. Train B EDG 2G003 local frequency indication had been declared inoperable, because of a failed channel check, on 1 October 22,1997.. The inspectors reviewed Equipment Deficiency Mode - ;
Restraint E2 97-0513, generated as a result of the inoperable EDG 2G003 frequency ,
indication, and noted that, in the comments section, the operators were advised to '
" Maintain 2G002 and its L169 frequency indication operable or enter 30 day shutdown action "
The inspectors questioned the Unit 2 control room supervisor (CRS) at about 9:45 on December 2,1997, concerning the fai'ure to enter TS 3.3.12. In ret,ponse, the CRS -
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entered the TS immediately after being questioned. The inspectors found that both *
Operations Equipment Control and the operating crew should have identified this action -
prior to being prompted by the inspectors. Equipment Control was an Operations j organization responsible for identification of TS applicability for scheduled maintenanc '
This EDG 2G002 maintenance activity 'vas scheduled maintenanc The CRS wrote Limiting Condition for Operation Action Required 2 97 310 to .
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administratively track the LCO entry. Licensee programmatic controls provided for either an entry in the operating logs, and/or use of a limiting condition for operation action required tracking sheet, in order to document and track LCO entry and exit. The inspectors observed that the time of entry for the LCO discussed above was documented as 7:44 a.m., with no indication that the LCO was actually recognized and entered later. Neither the Unit 2 nor the common operating logs contained log entries showing LCO entry, and consequently did not indicate the late entry. Therefore, the ,
licensee did not have a written record to indicate that the LCO was entered at any time other than 7:44 a.m.10 CFR Part 50, Appendix B, Criterion XVil, states that " Sufficient
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records shall be maintained to fuinish evidence of activities affecting quality." TS LCO entry is a matter affecting quality. Contrary to this requirement, as described above, sufficient records were not maintained to indicate actual LCO entry time, which was necessary to describe the activity. This failure constitutes a violation of minor safety significance and is being treated as a noncited violation, consistent with Section IV of the NRC Enforcement Policy (NCV 361/97025-01). Conclusions Operations Equipment Control personnel and the operating crew failed to recognize an
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applicable TS action that should have been entered, until brought to their attention by the inspectors. No TS action times were exceeded; however, this failure demonstrated
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a weakness in attention to detail while assessing TS actions for equipment configuration. A noncited violation was identified for failing to create sufficient records,
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either in the operating logs or by separate LCO tracking sheets, to indicate that the action was entered lat Operator Training and Qualitication 05.1 ADilitute of Nuclear Power Ooerations Accreditation of Trainina Proorams
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The inspectors reviewed the Institute of Nuclear Power Operationa' report of the training program accreditation that had been performed at San Onofro from September 29 to October 3,1997. The report was forwarded to the licensee by a letter dated 1 December 8,1997, and did not reveal any significant problems not previously known to the NRC. The programs reviewed were; nonlicensed operator, reactor operator, cr.br reactor operator, shift manager, continued training of licensed personnel, and shift technical advisor. The accreditation of all six training programs was renewe .
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11. Malatenance Mi Conduct of Maintenance t
M1.1 Gaceral Comments Insoection Scoon (62707)
The inspectors observed all or portions of the following work activities:
e 1.ubricate EDG fuel oil motor bearings on transfer pumps (Unit 2)
e Replace missing bracket on EDG 2G002 exhaust pyrometer circuit tray (Unit 2)
- Calibrate EDG 2G002 fsel oil dry tank level float Column 2LCH5933-1 (Unit 2)
e Fuel handling building Train B vent radiation monitor troubleshoot and repair (Unit 3)
e Expansion joint repair on penetration cooling Fans 3A-415 and 3A-403 (Unit 3) Qhansations and Findings The inspectors found the work performed under these activities to be thorough All work !
observed was performed with the work package present and in active use. Technicians L
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were knowledgeable and professional. The inspectors frequently observed supervisors and system engineers monitoring job progress, and quality control personnel were present whenever required by procedure. When applicable _ appropriate radiation -
controls were in place, in addition, see the specific discussions of maintenance observed under Sections M and M3.1, belo .
M1.2 General Comments on Surveillance Activiting Insoection Scoce (61726)
The inspectors observed all or portions of the following surveillance activities:
o - Emergency safety features subgroup Relay K118 Trains A and B semiannual test procedure modification Permit 1 and 2, Test K118 safety injection actuation signal relay (Unit 2)
e AC sources verification (Unit 2)
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- - Fire suppression water system triennial flush (Units 2 and 3) *
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e Weekly electrical bus surveillance (Unit 3) I
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The inspectors found all surveillances performed under these activities to be thoroug All surveillances observed were performed with the work package present and in active use. Technicians were knowledgeable and professional. The inspectors frequently l observed supervisors and system engineers monitoring job progress, and quality control personnel were present whenever required by procedure, When applicable, appropriate radiation controls were in plac M1.3 Reolacement of EDG Trio Solenoid - Unit 2 insoection Scone (62707)
On November 18,1997, the inspectors observed Electrical Maintenance personnel replace a trip solenoid located in the Engine 1 governor for EDG 2G003. The inspectors reviewed MO 97101298000, used to perform the maintenance, and Action Request (AR) 970600175, used to document the indications received that required the replacement of the solenoi Observations and Findinos Control room operators had noted that intermittent DC grounds occurred when EDG 2G003 speed or load was changed. The EDG remained operable because the grounds were localized to the governor trip sol 1oid circuit. Alternate mechanical EDG trips existed to provide EDG protection, and a .purious EDG trip due to the intermittent ground was not considsred plausible. The DC circuit, by design, is not grounded. The DC circuit requires two separate grounds to disable the circuit; however, only one ,
ground was present in this instanc Electrical Maintenance personnel exhibited excellent skill of the craft while performing the maintenance. Specifically, in advance of the maintenance activity, the technicians had fabricated a plate that was used to stabilize the old solenoid while fluid connections were uncoupled during the maintenance. Use of foreign material control while the govemor was open was excellent. The initial ground isolation to the trip solenoid was good, considering that the ground was intermittent. The MO did not specify which engine governor to perform the replacement on. The EDGs are tandem machines, with two engines and one generator per EDG. The technicians, however, performed the replacement on the correct engin When the technicians removed the old trip solenoid (manufactured by Woodward Governor ompany, Type 82340-507), they noted that the two wire leads were
. connected at the base of the cylindrical solenoid, traveled under the solenoid, and were clamped to the side of the solenoid. One of the wires had been contacting a nut,
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i associated with the fuel racks, on the bottom of the solenoid. The nut had abraded the wire *"tation, causing the grounds. The replacement solenoid had the wire leads tra irectly up the side of the solenoid, and did not have the wires positioned urder the . .old. Consequently, there would be no contact between the nut and the i replacement solenoid leads. Configuration of the wire leads could be either directed t under the solenoid, or directly up the side, depending on the positioning of the wire clamp on the side of the solenoi i
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The licensee planned on checking the other Unit 2 diesel and both Unit 3 diesels, at the-next available opportunity, to ensure that those trip solenoid leads were routed so as not ,
to facihtate grounding. The inspectors considered this acceptabl l Conclusions Electrical Ma!ntenance personnel demonstrated excellent skill o' the craft while [
replacing an EDG governor trip solenold. The MO used to perform the task was not -
sufficiently prescriptive because the EDG engine governor to be worked was not .
stipulated; however, this oversight was compensated for by alert technician '
i M2 Maintenance and Material Condition of Facilities and Equipment
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M2.1 Review of Material Condition Durino Plant Toya Insoectica Scoce (62707)
During this inspection period, the inspectors performed routine plant tours and evaluated plant material conditio ' Observations and Findings On November 13,1997, the inspectors identified that the Train B Emergency Chiller E336 Freon space monitor was in alarm. The chiller was in operation for testing purposes. The inspectors informed the control room operators, who initiated oxygen monitonng of the space. The oxygen levels were normal and the monitor was determined to bo inoperable. Appropriate compensatory actions were taken until the monitor was repaire During various plant tours the inspectors identified a small number of fasteners missing from safety related electricaljunction boxes. The licensee's Work It-Now team promptly
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corrected these deficienciesc '
During various plant tours the inspectors observed very few general area lights that were not lit. This represented a significant improvement over lighting conditions observed in recent month '
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On November 17, the inspectors observed steam coming from Unit 2 auxiliary feedwater pump governor Valve 2SV4700 and informed the shift superintendent. The shift superintendent identified a previous AR written on the steam leak while the pump was operating, but not when it was stopped. The licensee performed an operability -
assessment and concluded that the pump was operable. The inspectors concluded that the licensee's actions were acceptabl During various plant tours the inspectors identified two valves that had small amounts of ,
dry boric acid built up on the valve butt plates. The licensee determined that the boric acid was not contaminated, and initiated ARs to correct the conditio ,
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On December 9,1997, the inspectors identified that a ground strap was not installed on ,
the motor housing for Valve 3HV9336, the low pressure safety injection suction valve from shutdown cooling. A ground wire clip was installed on the housing. The licensee determined that the housing was prooerly grounded through the conduit. The licensee reviewed records and determined that a strap had never been installed on the motor housing. The licensee decided to install a grounding strap to make the configuration consistent with the other motor operated valves la the vicinit The inspectors observed that the licensee was continuing preservation efforts in the Unit 2 auxiliary feedwater pump room and in the Unit 3 charging pump rooms, Conclusions .
Material condition throughout the units was very good, with some minor deficiencies identified by the inspectors. The licensee promptly initiated corrective actions for the identified deficiencie M3 Maintenance Procedures and Documentation M3.1 BAMU Pumo Paintina Unit 2 Insoection Scooe (62707)
The inspectors reviewed the MO associated with painting and inadvertent plugging of i the BAMU pump bearing case vent, the associated AR, and Procedure SO123 I 1.11,
" Site Painting Procedure," Revision 1. In addition, the inspectors discussed the problem with Maintenance supervision and Station Technical, Observations and Findings On November 17,1997, during a BAMU pump e r.a. the licensee identified that thr, vent path in the bearing casing was blocked and caused pressure to increase in the bearing casing The pressure increase caused bearing lubricating oil to be forced out at the
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base of the constant oiler (chicken feeder). The licensee cleared the vent paths, monitored the pump performance, and declared the pump operabl :
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The inspectors discussed the cause of the blocked bearing casing vent with .
Maintenance supervision. Maintenance supervision determined that the bearing casing ;
was repaired and painted in the machine shop. The casing was then reinstalled in the plant and the pump was returned to service. On November 14, painters performed touch up paintirsg of the affected areas of the pump. A licensee general foreman did not recognize that what appeared to be a capped pipe was actually the bearing casing vent -
and directed contractor painters to paint the vent. Maintenance supervision determined that the cause of the blockage was due to paint applied to the vent cap during touch up paintin The licensee performed several corrective actions as a result of the painting of the bearing casing. The licensee immediately checked the other BAMU pumps for potential bearing casing vent blockage, and found none. Maintenance supervision performed a lessons learned overview with the painters. The licensee generated an assignment to create an identification tag for the vent. The licensee planned to evaluate the need to have component / system expertise available when painting on safety related equipmen The inspectors reviewed the MO and concluded that the instruction provided to the painters to paint the bearing casing vent was not appropriata to the circumstances. The failure to provide the painters instructions appropriate to the circumstances was a violation of 10 CFR Part 50, Appendix B, Criteria V. This nonrepetitive, licensee identified and corrected violation is being treated as a noncited violation, consistent with Section Vll.B.1 of the NRC Enforcement Poliev (NCV 361/97025-02). Conclusions A noncited violation was identified as a result of Maintenance personnel painting over the vent of a BAMU pump due to inappropriate instructions provided to the painter The licensee's immediate corrective actions to restore BAMU pump operability and perform visualinspections of the remaining BAMU pumps was good. In addition, the completed and planned corrective actions were thorough and comprehensiv .
Ill. Engineerina E2 Engineering Support of Facilities and Equipment E2.1 Minimum Number of Pressydzer Heaters Reauired for Plant Ooeration (Unit 3) Insoection Scoce (37551)
The inspectors reviewed the licensee's assessments of the minimum number of pressurizer heaters required for plant operation, including Nonconformance Report s (NCR) 970600611; ARs 971001045, 971100322, 971200172, and 971200758; the Updated Final Safety Analysis Report (UFSAR); the reactor coolant system design basis Document, DBD SO23 360, Revision 4; J. D. Moore memorandum to file. * Minimum Recommended Number of Pressurizer Heaters for Plant Operation," dated
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-8 May 23,1995; and Calculation M-0011-068, * Minimum Quantity of Pressurizer Heaters for Plant Operation,' dated December 4,199 Observations and Findinos The pressurizer was designed with 30 heaters, of 50 kW eac TS LCO 3.4.9 requires that "the pressurizer shall be Operable . , , with two groups of pressurizer heaters Operable with the capacity of each group a 150 kW and capable of being powered from an emergency power supply." This is accomplished by having at !
least three heaters connected to each of two Class 1E backup heater bank i UFSAR Section 5.4.10.1 states that one of the design bases of the pressurizer is to
" ensure that the minimum pressure observed during transients is above the setpoint of the safety injection actuation signal." The pressurizer heaters are not relied on to satisfy this requirement during significant plant transients, such as reactor trip NCR 970600611, dated June 1997, stated in the 10 CFR Part 50.59 Safety Evaluation that Nuclear Engineering Design's preliminary assessment of the minimum required number of operable heaters was 22. The NCR Notes stated that an additional three heaters could be inoperable and still be acceptable, based on San Onofre having less ambient heat loss that had been assumed in the analysis. The analysis had been based on a comparison with a Palo Verde study, documented in the May 23,1995, memorandum to fil AR 971001045 documented that as of October 22,1997, eight Unit 3 pressurizar heaters were failed and out of service. The eighth failure occurred on July 27, .'47, and was also documented in AR 970701447. This left 22 heaters in service, which was the limit determined in NCR 97060061 AR 971100322, dated November 6,1997, documented the failure of the ninth pressurizer heater in Unit 3. No assessment of the operationalimpact of this adoitional failure was documented with this AR, except that an operability assessment was not required because the heater was declared inoperabl ,
Nuclear Engineering Design issued Calculation M-0011068 on December 4,1997. This calculation provided the minimum number of operable heaters for various plant conditions, including various actual ambient heat loss rates, and assumed some specific methods of plant operation, such as how heaters were controlled while forcing pressurizer spray AR 971200172, dated December 4,1997, documented that Calculation M-0011068 concluded that insufficient heater capacity existed for normal plant control during the condition when two reactor coolant pumps were running and auxiliary spray was in service. The AR recommended ways that the condition could be avoide .
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AR 971200758 documented the failure of the tenth Unit 3 pressurizer heater on .
December 13,199 ;
After the failure of the ninth heater, on November 6,1997, until the issuance of Calculation M 0011068 on December 4,1997, the only formal guidance available to !
operators was that the minimum number of heaters was 22. During this period only 21 heaters were operablo in Unit r The shift superintendent and the CRS for Unit 3 on December 13,1997, were not aware of Calculation M 0011-068. When questioned, the Unit 3 CRS stated that only the six Class 1E powered heaters were required. This was consistent with verbal guidance provided to the operators by Operations management, with the unstated addition that there had to be enough heaters to maintain normal system pressur The inspectors met with licensee personnel on December 15,1997, and determined that ;
Nuclear Engineering Design had been studying the minimum number of heaters required since approximately March 1997. Additionally, Nuclear Engineering Design ,
had presented information to Operations management and other management personnel in October 1997 incicating that the minimum number of operable heatera would be in the vicinity of 14 to 16. Although this was not documented in a formal document available to operators, this demonstrated that the licensee had preliminarily determined that operation with the nine failed heaters was acceptable. Some personnel on the AR Commi!!ee were aware of the preliminary results of the Nuclear Engineering Declgn evaluation. This Committee was respons!ble for assessing the response in failure of the ninth heater, CDaClusiont Nuclear Sesign Engineering's ongoing assessment of the minimum number of opersble presserizer heaters to support plant operations was timely. However, the communication of the preliminary results to Operations was informal, and between November 6 and De: ember 4, the arr'ysis of record did not support operation with the number of heaters that were in serv t . Operations management had provided appropriate guidance to the operators, based on the preliminary results of Engineering's ongoing assessment. At all times, TS requirements were satisfie E4 Engineering Staff Knowledge and Performance E4.1 - OperabilityAltisment of the BAMU Punto - Unit 2 Inspection Snooe (37551)
The Mspectors reviewed the licensee's operability assessment of the BAMU pump that had the bearing casing vent plugged and discussed the assessment with Station Technica *
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-10- Observations and Findings The inspectors observad that the assessment justified the operability of the pump folbwing completion of sepairs to the pump, but did not assess the operability of the pump in the degraded candition with the bearing casing vent plugged. The inspectors discussed the observation with Station Technical personnal, who confirmed that the assessment did not evaluate the dagraded, as found condition of the pump. Therefore, Station Technical modified the operability assessment and concluded that the pump would have been capable of performing its design function during an event, and, with credit for operator rounds, would have remained operable during normal plant operations that included multiple start Conclusions The initial operab'ity assessment performed by Station Technical was not thorough in that it did not evaluate the degraded condition of the BAMU pump with the bearing casing vent plugged. The modified operability assessment exhibited a detailed assessment of the degraded as found condition of the BAMU pum E3 Miscellaneous Engineering issues (92903,92700)
E (Closed) Unresolved item 50 361: 362/97012-07: charging nystem check valve failures, ID$pection Scoce (92902)
This item involved reviewing the formal licensee root cause determination for failures of 2 inch Kerotest check valves in the Units 2 and 3 charging system. The inspectors reviewed Quality Engineering Rcot Cause Determination RCE 97 003, "2-inch Kerotest Check Valves Limited Stroke " and Procedure SO23-3 3.31.5, "CVCS/PZR Spray Valve Testing-Cold Ghutdown and Refueling Interval," Revision 2. The inspectors also reviewed portions of the UFSAR, TS, and applicable portions of the ASME Code describing insarvice testing requirements for check valves, in addition, NRC Generic Letter 09-04, Attachment 1, a summary of inservice testing results for Units 2 and 3 Valves $2(3)1201MUO21 and S2(3)1201MUO19, since 1986, and records of postinstallation tetting for Valves S2(3)1201MUO21 were reviewe Obiervations and Findings The root cause evaluation was thorough and probing. Decign review of the Kerotest Model 1513,2 inch. stainless steel, Y check valves was performed by the licensee, as well as Kalsi Engineering, an independent engineering firm. The cylindrical disk in these valves was found to be restricted from traveling to the open position, as soon as it lifted ,
a small amount off its seat, because a vent path for the top of the disc was not large l enough to compensate for leakage between the disk and v:lve body. As a result, there was insufficient upward force on the disk to overcome inctiors between the valve body and the disk guide,
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-11 The principal valves affected were Units 2 and 3 Valves S2(3)1201MUO21, the Loop 1 A charging line check valves. These valves' checking mechanism were found to have extremely limited upward travel. The UFSAR Chapter 15 SBLOCA analysis, as reflected in the TS bases, assumed 15.9 gpm charging flow delivered to the core to assure acceptable fuel clad temperatures. Since Valves S2(3)1201MUO21 were severely limited as to did travelin the open direction, most charging flow during normal operation was found to bs. flowing through Valves S2(3)1201MUO20, the Loop 2A charging line check valves. As documented in NRC Inspection Report 50 361; 362/97-12, the licensee entered TS shutdown actions for insufficient emergency core cooling system (ECCS) flow, and shut down Unit 2 (Unit 3 was already shut down) to replace these valves. Since the Chapter 15 analysis assumed 15.9 gpm during SBLOCA analysis, and since a break in Loop 2 would cause less than 15.9 gpm flow to be delivered to the core (the flow would go out the break, with the head loss due to the partially stuck check valve restricting flow to the intact Loop 1), the inspectors determined that the units were in a potentially unanalyzed condition. The inspectors were informed by the licensee, however, that an analysis had been submitted to NRR for review, which concluded that charging flow was not required for mitigation of any size LOC Procedure SO23 3 3.31.5 was used to perform the licensee-controlled specification required in service testing of Check Valves S2(3)1201MUO21. The testing was performed on a cold shutdown interval, with the reactor coolant system generally at 350 psig. Two charging pumps were operating and Valves S2(3)1201MUO20 were isolated, resulting in the only charging flow path through Valves S2(3)1201MU21, to the reartor coolant system. The acceptance criteria was 80 gpm, with each charging pump ratt ' at 44 gom. Differential pressure across the check valve, and disk movement, was not measured. Although open movement for Valves S2(3)1201MUO21 was restricted, data indicated that the valves passed all forward flow testing. This was because the positive displacement pump produced a constant flow regardless of system configuratio CFR Part 50, Appendix B, Criterion XI, states, in part, that a test program is required to demonstrate that all components will perform satisfactorily in service, and that acceptance limits contained in applicable design documents are incorporated. As described above, and stated in TS bases, Valve S2(3)1201MUO21 is required to pass 15.9 gpm of the 36.2 gpm charging flow assumed during a SBLOCA, by design, when operated in parallel with Valves S2(3)1201MUO20. Due to the extremely limited opp disk travel, Valves S2(3)1201MUO21 were unable to pass this required flow, when operated in parallel with Valves S2(3)1201MUO20, as assumed in the design. The inspectors reviewed postinstallation testing records for Unit 3 Valves S31201MUO21 (installed b 1993) and Unit 2 Valve S21201MU021 (installed in 1985, as reflected in Licensco Event Report (LER) 50 361; 362/97 010-01), and found that after these redesigned valves were installed, an inservice test, as described above, was performe No measurement of flow, with the valves operated in parallel with Valves S2(3)1201MUO20 was performed. As described above, Valves S2(3)1201MUO21 did not perform satisfactorily in service (Violation 361; 362/97025,03).
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-12 The inspectors reviewed licensee correc0ve actions as stated in '
, LER 50 301; 362/97-010-01 and RCE 97 003. Valves S2(3)1201MUO21 and S2(3)1201MUO19 (the charging to auxiliary spray check valve) were replaced in both units with valves manufactured by 9 different vendor. Testing to ensure a flow balance between both charging lines to the reactor coolant system was performed. The licensee ,
planned on revising the inservice testing requirements for Valves S2(3)1201MUO21 to .
Include differential pressure measurement across the valves, to verify proper disk trave '
The inspectors found these corrective actions adequately addressed the violation, and
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no further response is require i Conclusions -
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A thorough and probing root cause analysis of the failure of Kerotest 2 inch charging system check valves was performed. A violation was identified because adequate i testing was not performed on the Units 2 and 3 charging line to Loop 1 A check valves, in that a design SBLOCA system flow requirement was not verified. This resulted in both Units 2 and 3 operating in an unanalyzed condition for some period of time. An analysis was under review by NRR that concluded that charging flow was not required for LOCA mitigatio '
E (Closed) Violation 50 361: 362/97017-05: incorrect nondestructive examination acceptance criteria used. The inspectors verified the corrective actions desenbed in the licensee's response letter, dated October 6,1997, to be reasonable and complete. No similar problems were identifie E8.3 (Closed) LER 50-361/97-015 00: Inadequate surveillance testing of charging pump relay contacts. - Inspection Scoce (92700)
On November 17,1997, licensee engineers reviewed information received from t.nother nuclear power plant, and identified that a contact that disables two charging pump trips, '
which are disabled during a safety injection signal automatic pump start, was not being surveilled. The licensee utilized the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period authorized by TS Survelhance Requirement (SR) 3.0.3, and successfully tested these contacts in Units 2 and 3. The inspectors observed portions of this testing, and reviewed SO23-3 3.43.6,"ESF Subgroup Relays K 1088 Semlannual Test," Revision 3. The inspectors also reviewed various charging pump start circuit electrical drawings and NRC Generic Letter 96 01,
" Testing of Safety Related Logic Circuits," and the licensee response to this letter, letters from Mr. Walt C. Marsh, Manager of Nuclear Regulatory Affairs to the NRC Document Control Desk dated April 18,1996, and August 20,199 , QbstIyaliQns and Findings Contact K108 in the charging pumpa start circuit opens on a safety injection actuation signal to defeat low suction pressure and high pressurizer level automatic charging
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13-pump trips. The licensee determined that subgroup relays actuated by this contact were not being tested during performance of Procedure SO23 3-3.43.6, used to satisfy TS SR 3.5.2.8. This SR states to " Verify each ECCS pump starts automatically on an actual or simulated actuation signal" each 24 months. TS 5.5.1.1.a states, in part, that written procedures shall be implemented covering procedures recommended in Regulatory Guide 1.33, Revision 2, Appendix A, February 197 Procedure SO23 3-3.43.6 was applicable to this regui tory guide. Since testing the K108 contact subgroup re ays is required duing verifice 4 nf ECCS pump starts, and since the charging pumps are ECCS pumps. Procedure 6023 3 3.43.6 was inadequate and a violation of TS 5.5.1.1.a occurred. Licensee response to NRC Generic Letter 96-01 indicated that all applicable ele:trical schematic drawings had beon reviewed and any instances in which survel' lance procedures did not adequately test all components would be corrected. The contact mentioned above was not identified during this review, which was complete before November 17,1997. Licensee corrective actions included testing the K108 contacts, and planning on conducting a new Generic Letter 96-01 review. Design engineers were also scheduled to receive training on this issue and the need for independent reviews of quality efecting work. This nonrepetitive, licensee identified and corrected violation is being treatt J as a noncited violation, consistent with Section Vll B.1 of the NRC Enforcement Policy (NCV 301; 362/97025 04). Conclusions A noncited violation was identified for failing to implement an adequate charging pump surveillence procedure that tested all contacts in the start circuitry. The licensee had previously reviewed this procedure in response to NRC Generic Letter 06-01, but had failed to identify the inadequacy, demonstrGting a less than thorough evaluation by Nuclear Engineering Design in conducting the revie IV. Plant Suncort P5 Staff Training and Qualification in Emergency Preparedness P Medical Emeroency Drilj IDsoection Scoce (71750)
The inspectors reviewed the SONGS Emergency Plan and the medical emergency drill critique. In addition, the inspectors discussed the personnel performance during the drill with the technical specialist for offsite emergency plannin Observations and Findings
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On November 13,1997, the licensee performed an annual medical emergency drill as required by SONGS Emergency Plan, Step 8.1.3.3. The San Onofre firefighters and secunty officers demonstrated the ability to respond to a contaminated, injurtJ, or
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l-14-exposed individual. Health physics (HP) personnel demonstrated the ability to respond -
to a radiation medical emergency - -
The licensee identified strengths in HP supervision, patient medical condition prioritization, and firefighter response. The licensee identified weaknesses in the
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performance of some HP technicians and planned to previde additional training to HP to i address the deficiencie l Conclusions
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The licensee was self entical in the identification of strengths ar'd performance issues i
during a medical emergency drill. The drill provided valuable tr.31ning for emergency .i response personne l V. Manaaement Meetinas
X1 Exit Meeting Summary )
- The inspectors presented the inspection results to members of licensee management at !
the exit meetireg on December 17,1997. The licensee acknowledged the findings '
presente i The inspet, tors asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identifie :
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ATTACHMENT SUPPLEMENTAL INFORMATION
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PARTIAL LIST OF PERSONS CONTACTED
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Licensee D. Brieg, Manager, Station Technical J. Clark, Manager, Chernistry J. Fee, Manager, Maintmance G. Gibson, Manager, Ccmpliance D. Herbst, Manager, Site Qualit< Assurance J. Madigan, Manager, Hulth Physics (Acting)
R. Kr!cgSr, Vice Presiderd. Nuclear Generation D. Nunn, Vice President, Engineering and Technical Services T. Vogt, Plant Superinten: lent, Units 2 and 3 R. Waido, Manager, Operations INSPECTION PROCEDURES USED IP 37551: Onsite Enginaring IP 61726: Surveniance Observations IP 62707: Maintenance Observations IP 71707: Plant Operations IP 71750:- - Plant Support Activities IP 92700: On Site LER Review IP 92903: Followup - Enginecting jIEMS OPENED AND CLOSED Onened and Closed 50-361/97025-01 NCV LCO entry time not Indicated 50 361/97025-02 NCV inappropriate instructions for BAMU pump painting 50-361/97025-03 VIO- testing of charging system check valves 50-361/97025-04 NCV inadequate surveillance testing cf charging pump relay contacts C101td '
-50 361;362/97012-07 - - URI charging system check valve failures
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50 361;362/97017-05- VIO incorrect nondestructive enmination acceptance criteria -
used 50-361/97-015-00 LER inadequate surveillance testing of charging pump relay contacts Ll,1T OF ACRONYMS USEQ AR - action request BAMU boric acid makeup CRS control room supervisor ECCS emergency core coolinD system EDG emergency diesel generator ;
HP . Health Physics ;
LCO limiting condition for operation LER licensee event reoort LOCA loss of coolant a cident MO maintenance order NCR nonconformance report NRR NRC Office of Nuclear Reactor Regulation PDR Public Document Room SBLOCA small break loss of coolant accident 4
.SR surveillance requirement TS technical specification UFSAR Updated Final Safety Analysis Report
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