IR 05000416/1998002

Insp Rept 50-416/98-02 on 980222-0404.No Violations Noted. Major Areas Inspected:Operations,Maint,Engineering & Plant Support

ML20217B409
Person / Time
Site:	Grand Gulf
Issue date:	04/15/1998
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
Shared Package
ML20217B393	List: IR 05000416/1998002 ML20217B387
References
50-416-98-02, 50-416-98-2, NUDOCS 9804230031
Download: ML20217B409 (9)

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ENCLOSURE 1 U.S. NUCLEAR REGULATORY COMMISSION

REGION IV

l Docket No.: 50-416 License No.: NPF-29 Report No.: 50-416/98-02 Licensee: Entergy Operations, In Facility: Grand Gulf Nuclear Station Location: Waterloo Road Port Gibson, Mississippi Dates: February 22 through April 4,1998 Inspector (s): J. Dixon-Herrity, Senior Resident inspector K. Weaver, Resident inspector Approved By: D. Kirsch, Chief, Project Branch F Division of Reactor Projects

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i Attachment: SupplementalInformation 9E04230031 980415 PDR ADOCK 05000416 G PDR

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EXECUTIVE SUMMARY Grand Gulf Nuclear Station NRC Inspection Report 50-416/98-02 Ooerations

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The inspectors observed good three-way communications within operations and that the operations shift turnovers were thorough and conducted professionally (Section 01.4).

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Operations personnel response to the trip of reactor feed Pump B was good and in accordance with procedures (Section 01.4).

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Operators were very knowledgeable of the test conducted to allow increasing the plant to full power with a bias between the feed pumps. The briefing conducted for this test was thorough and the licensee returned to approximately 98 percent power in a controlled, conservative manner (Section 01.4).

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The actions taken by the licensee in response to a potential concern over the operability of Unit 1 safety-related valves due to cracks found in the yokes on similar spare valves from the abandoned Unit 2 plant were conservative and thorough (Section E1.2). I k

Maintenance

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Maintenance and testing activities were performed properly. One example of good attention to detail was observed when a nonficensed operator called attention to an f

i improperly sealed door on the control room fresh air unit (Section M1.3).

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Maintenance technicians exhibited good attention to detail by identifying cracks in the yokes on spare valves from the abandoned Unit 2 plant while preparing the valves for modification (Section E1.2).

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The test instruction and safety evaluation, developed to allow running the reactor feedpumps at mismatched flowrates, were detailed and technically sound (Section E1.1).

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The evaluations conducted as a result of the discovery of cracks in the yokes of spare valves from the abandoned Unit 2 plant were thorough and based on both fact and good engineering judgement (Section E1.2).

Plant Sucoort

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The support provided by radiation protection personnel during diving operations in the refueling pool was very good. The preparation for the job was detailed, personnel were aware of radiation concerns and followed procedures, and very close controls were maintained over the diver's dose (Section R1.2).

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Reoort Details i Summarv of Plant Status At the beginning of the inspection period the plant was operating at approximately 98 percent power. On March 5,1998, reactor feed Pump B tripped, and power was reduced to l

approximately 72 percent. The plant remained at approximately 70 percent power until )

March 8. After completing troubleshooting activities for the reactor feed Pump B governor controls, reactor feed Pump B was placed back in service and reactor power was increased to approximately 98 percent. The plant remained at approximately 98 percent power until the end of the inspection perio l. Operations 01 Conduct of Operations 01.1 General Comments (71707) -

The inspectors performed control room observations to ascertain operator knowledge and performance. Operators demonstrated good three-way communications and peer review. Operations shift turnovers were thorough and conducted professionall Operators were knowledgeable of the status of equipment and applicable Technical Specification limiting conditions for operation were appropriately documente .2 Reactor Feed Pumo B Trio (71707)

On March 5,1998, reactor feed Pump B tripped due to an apparent servo-control valve i

i fault. This condition initiated a recirculation pump flow control valve runback, reducing

' reactor power to approximately 72 percent. All systems responded as expecte Operators appropriately entered the off-normal procedures for loss of feedwater flow and decrease in recirculation flow. The licensee later determined that the apparent cause was mechanical binding of at least one of the low pressure admission poppet valves. The licensee plans to complete the root cause analysis following repair of the valve during Refueling Outage 9, scheduled to begin in April 199 .3 Power Ascension On March 8,1998, the inspectors observed licensee preparations to return the plant to 98 percent power after the March 5 reactor feed pump trip and the prejob briefing given by engineering for operations personnel prior to increasing power. The special test that was performed is discussed further in Section E1.1. The discussions held between management, engineering, and operations were detailed and thorough and all individuals involved had a good understanding of the affects the change would have on the plant. Through discussions with operators in the control room, the inspectors observed that the operators had a very good understanding of the test and were monitoring the plant. Work that could have an effect on the plant was held up until the test was complete .

-2-l 01.4 Conclusions for Conduct of Ooerations The inspectors observed good three-way communications within operations and that the operations shift turnovers were thorough and conducted professionally. Operations personnel response to the trip of reactor feed Pump B was good and in accordance with procedures. Operators were very knowledgeable of the test conducted to allow increasing the plant to full power with a bias between the feed pumps. The briefing conducted for this test was thorough and the licensee returned the plant to approximately 98 percent power in a controlled, conservative manne II. Maintenance M1 Conduct of Maintenance M1.1 General Maintenance Comments Insoection Scoce (627QZ)

The inspectors observed portions of maintenance activities, as specified by the following work orders (WOs):

- WO 200797 Control room emergency filter system heater check

- WO 165434 Full open test suppression pool makeup check Valve 1E30F0038

- WO 184419 Replacement of horizontal fuel transfer system proximity probe Observations and Findinas The inspectors found the performance of the tasks observed was satisfactory. All work was conducted in accordance with the instructions and procedures provided in the work packages. Good radio communications were observed between maintenance craft, nonlicensed operators, and control room operators during the control room envelope breach while performing WO 200797. The personnel involved in the planning and performance of WO 184419 were very cognizant of all the details of the work and the planning was thorough. Maintenance personnel were knowledgeable of the work being conducted and the radiation conditions and procedures in the areas that they were workin Good attention to detail was displayed by the nonlicensed operator involved with WO 200797, in that the operator identified leakage into control room fresh air Unit B while the system was running. The door to the carbon filter was not latched properl When the operator notified control room operators, Unit B was shutdown, the door latched properly, and Unit B was run again to ensure that the door sealed properly. No

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-2-01.4 Conclusions for Conduct of Ooerations The inspectors observed good three-way communications within operations and that the operations shift turnovers were thorough and conducted professionally. Operations personnel response to the trip of reactor feed Pump B was good and in accordance with procedures. Operators were very knowledgeable of the test conducted to allow increasing the plant to full power with a bias between the feed pumps. The briefing conducted for this test was thorough and the licensee returned the plant to approximately 98 percent power in a controlled, conservative manne ll. Maintenance M1 Conduct of Maintenance M1.1 General Maintenance Comments Insoection Scoce (62707)

The inspectors observed portions of maintenance activities, as specified by the following work orders (WOs):

WO 200797 Control room emergency filter system heater check

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WO 165434 Full open test suppression pool makeup check Valve 1E30F0038

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WO 184419 Replacement of horizontal fuel transfer system proximity probe Observations and Findinos The inspectors found the performance of the tasks observed was satisfactory. All work was conducted in accordance with the instructions and procedures provided in the work packages. Good radio communications were observed between maintenance craft, nonlicensed operators, and control room operators during the control room envelope breach while performing WO 200797. The personnel involved in the planning and performance of WO 184419 were very cognizant of all the details of the work and the planning was thorough. Maintenance personnel were knowledgeable of the work being conducted and the radiation conditions and procedures in the areas that they were workin Good attention to detail was displayed by the nonlicensed operator involved with WO 200797, in that the operator identified leakage into control room fresh air Unit B while the system was running. The door to the carbon filter was not latched properl When the operator notified control room operators, Unit B was shutdown, the door latched properly, and Unit B was run again to ensure that the door sealed property. No

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-3-CR 1998-0259 the design leakage was subsequently identified. The licensee control room leak rate limit to be exceede M1.2 General Surveillance Comments

\ Insoection Scoce (617261

/ t listed The inspectors observed the performance of portions of the surveillance below: Heat

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Procedure 06-OP-1E-O-0025, " Low Pressure Coolant injection /

Removal Subsystem C Ouarterly Functional Test"

Procedure 06-EL-1821-0-0001, " Automatic Depressurization Sy FunctionalTest and Calibration"

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Procedure 06-OP-1P75-R-0003, " Standby Diesel Generator 11 1 Functional Test" Observations and Findinos id In general, the inspectors observed thatt dthe i and quipment test test procedures pro and properly implemented Technical Specification ntered, and requirements. Mea equipment were verified to be within the current i calibration cycle. Tes was removed from service, applicable limiting conditions d qualifie for operat on e properly returned to service. Technicians were very knowledgeable As-found test data was within the tolerance established t for this e inspectors checked that the tests had been previously performed a periodicit M _

C onclusions for Conduct of Maintenance d Maintenance and testing activities were performed tt tion to an properly. One attention to detail was observed when a nonlicensed operator called a e improperly sealed door on the control room fresh air uni .

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-3-leakage was subsequently identified. The licensee immediately initiated CR 1998-0259 and determined that the additional leakage through the door did not cause the design control room leak rate limit to be exceede , M1.2 General Surveillance Comments Insoection Scooe (61726)

The inspectors observed the performance of portions of the surveillance tests listed below:

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Procedure 06-OP-1E-Q-0025, " Low Pressure Coolant injection / Residual, Heat Removal Subsystem C Quarterly Functional Test"

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Procedure 06-EL-1821-0-0001, " Automatic Depressurization System Timers Functional Test and Calibration"

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Procedure 06-OP-1P75-R-0003, " Standby Diesel Generator 11 18-Month Functional Test" Observations and Findinas in general, the inspectors observed that the test procedures provided clear guidance and properly implemented Technical Specification requirements. Measuring and test equipment were verified to be within the current calibration cycle. Tested equipment was removed from service, applicable limiting conditions for operation entered, and properly returned to service. Technicians were very knowledgeable and qualifie As-found test data was within the tolerance established for this equipment. The inspectors checked that the tests had been previously performed at the correct periodicit M1.3 Conclusions for Conduct of Maintenance Maintenance and testing activities were performed properly. One example of good attention to detail was observed when a nonlicensed operator called attention to an improperly sealed door on the control room fresh air unit.

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-4-lli. Engineering E1 Conduct of Engineering E Test to Allow Runnino Feed Pumos with a Bias Offset l I Insoection Scooe (37551)

The inspectors reviewed the test instruction and the 10 CFR 50.59 Safety Evaluation for the subject tes Observations and Findings l

The test instruction was written to allow data collection for establishing control valve position limits for reactor feed pump Turbine B while running the reactor feed pumps at mismatched flowrates. The mismatched flowrate was achieved by inserting a bias signalinto the feedwater control system on reactor feed Pump B. The fictnsee planned to insert the bias to allow operation closer to 98 percent power, while preventing control valves on reactor feed pump Turbine B from operating in the area where mechanical binding had occurred. This bias was to remain until the valve could be repaired during the next outage (scheduled to begin in April). Conclusions The test instruction and safety evaluation, developed to allow running the reactor feed pumps at mismatched flowrates, were detailed and technically soun E1.2 William Powell Valve Yoke Cracks Insoection Scoce (37551)

The inspectors reviewed the engineering evaluations performed to support an operability determination to be completed for William Powell valves used in Unit Observations and Findings On March 19,1998, while preparing several valve yokes from Unit 2 (a canceled unit)

for modification and installation in Unit 1, maintenance personnel discovered thin hairline cracks in the valve yokes. Further examination revealed that six valve yokes removed from Unit 2 had similar cracks. Engineering personnel performed an evaluation to determine the effect these cracks would have on the operability of valves from the same manufacturer in safety-related systems in Unit 1. The licensee's assumption that the Unit i valves had the same problem was conservative. Immediate actions included checking for similar indications on assessable safety-related valves, sending the yoke with the worst cracks offsite for fracture mechanic testing, rescheduling all safety-related l

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-5-work until the operability assessment was complete, and contacting the vendor to determine if there were any similar problems in industr The inspectors reviewed the engineering evaluation completed after the information from thu fracture analysis was available (dated March 26,1998).The cracks were hot tears (a fracture formed during solidification after casting because of hindered contraction). The specification required to be used for inspection for these castings did not allow visible hot tears or cracks. These tears were only visible after grinding and surface preparation, so the yokes met the inspection specification. Using the maximum flaw size in the Unit 2 valves and actual plant loads in Unit 1, the engineer determined that the valves were structurally sound and would perform their safety functio Conclusions The evaluations conducted as a result of the discovery of cracks in the yokes of sp valves from the abandoned Unit 2 plant were thorough and based on both fact an identifying cracks in i,le yokes on spare valves from the preparing the valves for modification. The actions taken by the licensee in response to a potential concern over the operability of Unit 1 safety-related valves due to cracks found in the yokes on similar spare valves from the abandoned Unit 2 plant were conservative and thoroug IV. Plant Suocort R1 Radiological Protecticn and Chemistry Controls R General Comments (71750)

The inspectors made frequent tours of the controlled access area and observed radiological postings and worker adherence to protective clothing requirements and radiation protection procedures. In general, locked high radiation doors were prop controlled, high radiation and contamination areas were properly posted, and personnel were following procedures. The licensee completed the installation of turnstiles at the access points to the controlled access area. The inspectors observed that training was provided and that mockups were set up to allow familiarization with the change prior to activating the new program. The inspectors observed that the licensee had not identified personnel entering the controlled access area without operable dosimetr since the installation of the turnstiles. This process will be further reviewed during t review of the corrective actions for NRC Violation 50-416/9714-0 R1.2 Divino Operations in Refuelino Pool Insoection Scoce (71750)

The inspectors observed the preparations for the subject work, the prejob briefing, a

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l portion of the work that was don Observations and Findinas l

The licensee determined that the most effective way to repair a fuel system proximity '

probe was to have a diver replace the probe. The licensee contacted other licensees who had performed the task using a diver. The instructions and plans were thoroug The licensee hydro blasted the area the diver would be working in several days before the job to ensure that the dose rate would be low. The prejob briefing and the health physics briefing on the area conditions were detailed and complete. All personnel involved had a clear understanding of the task to be performed and the conditions in the area.

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The inspectors observed the work and observed that the licensee had prepared very 1 l well for the task. All equipment was staged and all the tasks involved occurred in a

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timely manner. The diver was very well monitored by health physics throughout the i

dive. The licensee planned carefully, so that all time spent in the pool was productive.

j The only concem was that there was no easy means of communication between the l_

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diver and the electricians working with him up on the pool edge. The licensee also identified this concern and brought up communication equipment so that the electricians j

! would not have to yell across the pool to the workers communicating with the diver. The inspectors attended the critique held after the work was complete. All parties involved brought out astute points to identify where the job could have been improved.' These l included changing the way the contaminated area was laid out to allow better communication, different methods of staging tools, and additional contingencies that l should be considere Conclusions The support provided by radiation protection personnel during diving operations in the refueling pool was very good. The preparation for the job was detailed, personnel were

aware of radiation concems and followed procedures, and very close controls were l maintained over the diver's dos V. Manaaement Meetinos Xi Exit Meeting Summary l

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. The inspectors presented the inspection results to members of licensee management at the conclusion of the inspection on April 9,1998. The licensee acknowledged the findings

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presente The inspectors asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identified.

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l ATTACHMENT 1

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PARTIAL LIST OF PERSONS CONTACTED Licensee l

l D. Bost, Director, Design Engineering l C. Bottemiller, Superintendent, Plant Licensing

! L. Daughtery, Technical Coordinator, Plant Licensing

) W. Eaton, General Manager, Plant Operations C. Elisaesser, Manager, System Engineering

, J. Hagan, Vice President, Plant Operations l W. K. Hughey, Director, Nuclear Safety and Regulatory Affairs l

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R. Moomaw, Manager, Plant Maintenance J. Roberts, Director, Quality Programs J. Venable, Operations Manager

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NBC J. Donohew, NRR Project Manager i

INSPECTION PROCEDURES USED 37551 Onsite Engineering 61726 Surveillance Observations 62707 Maintenance Observation 71707 Plant Operations 71750 Plant Support Activities ITEMS OPENED. CLOSED. AND DISCUSSED Discussed 50-416/9714-01 Failure to comply with Technical Specification 5.7.1 t

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