IR 05000336/2006003

IR 05000336-06-003, 05000423-06-003; on 04/01/2006 - 06/30/2006; Millstone, Units 2 and Unit 3; Equipment Alignment, Operability Evaluations, Event Followup

ML062090543
Person / Time
Site:	Millstone
Issue date:	07/28/2006
From:	Paul Krohn NRC/RGN-I/DRP/PB6
To:	Christian D Dominion Resources
Krohn P, RI/DRP/PB6/610-337-5120
References
IR-06-003
Download: ML062090543 (35)

Text

uly 28, 2006

SUBJECT:

MILLSTONE POWER STATION - NRC INTEGRATED INSPECTION REPORT 05000336/2006003 AND 05000423/2006003

Dear Mr. Christian:

On June 30, 2006, the US Nuclear Regulatory Commission (NRC) completed an inspection at your Millstone Power Station Unit 2 and Unit 3. The enclosed inspection report documents the inspection results, which were discussed on July 11, 2006, with Mr. A. Skip Jordan and other members of your staff.

The inspection examined activities conducted under your license as they relate to safety and compliance with the Commissions rules and regulations and with the conditions of your license.

The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel.

This report documents three NRC-identified findings of very low safety significance (Green).

Two of these findings were determined to involve violations of NRC requirements. However, because of their very low safety significance and because are entered into your corrective action program, the NRC is treating these issues as non-cited violations (NCVs), in accordance with Section VI.A.1 of the NRCs Enforcement Policy. If you contest any NCV in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the Nuclear Regulatory Commission, ATTN.: Document Control Desk, Washington DC 20555-0001; with copies to the Regional Administrator, Region I; the Director, Office of Enforcement, United States Nuclear Regulatory Commission, Washington, DC 20555-0001; and the NRC Resident Inspector at the Millstone Power Station.

In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRCs document system (ADAMS). ADAMS is accessible from the NRC Website at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Paul G. Krohn, Chief Reactor Projects Branch 6 Division of Reactor Projects

Mr. D. Docket Nos.: 50-336, 50-423 License Nos.: DPR-65, NPF-49 Enclosure: Inspection Report 05000336/2006003 and 05000423/2006003 w/Attachment: Supplemental Information cc w/encl:

J. A. Price, Site Vice President, Millstone Station C. L. Funderburk, Director, Nuclear Licensing and Operations Support D. W. Dodson, Supervisor, Station Licensing L. M. Cuoco, Senior Counsel C. Brinkman, Manager, Washington Nuclear Operations J. Roy, Director of Operations, Massachusetts Municipal Wholesale Electric Company First Selectmen, Town of Waterford B. Sheehan, Co-Chair, NEAC E. Woollacott, Co-Chair, NEAC E. Wilds, Director, State of Connecticut SLO Designee J. Buckingham, Department of Public Utility Control G. Proios, Suffolk County Planning Dept.

R. Shadis, New England Coalition Staff G. Winslow, Citizens Regulatory Commission (CRC)

S. Comley, We The People D. Katz, Citizens Awareness Network (CAN)

R. Bassilakis, CAN J. M. Block, Attorney, CAN P. Eddy, Electric Division, Department of Public Service, State of New York P. Smith, President, New York State Energy Research and Development Authority J. Spath, SLO Designee, New York State Energy Research and Development Authority

Mr.

SUMMARY OF FINDINGS

IR 05000336/2006-003, 05000423/2006-003; 04/01/2006 - 06/30/2006; Millstone Power

Station, Unit 2 and Unit 3; Equipment Alignment, Operability Evaluations, Event Followup.

The report covered a 3-month period of inspection by resident inspectors and announced inspections by regional inspectors. Two (Green) non-cited violations (NCVs) and one (Green)finding were identified. The significance of most findings is indicated by their color (Green,

White, Yellow, Red) using Inspection Manual Chapter (IMC) 0609, "Significance Determination Process" (SDP). Findings for which the SDP does not apply may be Green or be assigned a severity level after NRC management review. The NRC's program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, "Reactor Oversight Process," Revision 3, dated July 2000.

Cornerstone: Initiating Events

Unit 3

!

Green.

The inspectors identified a Green NCV of 10 CFR 50, Appendix B,

Criterion III, Design Control, for an inadequate design change review for a steam generator low-low water level setpoint modification. Specifically,

Dominion did not fully consider the impact of the modification on the ability of the steam generator to accommodate operational transients without exceeding a parameter threshold which would require automatic or manual protective action.

This led to a reactor trip on December 1, 2005, while conducting a rapid downpower in response to a reactor coolant system leak from the packing of a loop maintenance stop valve that was collected in a drain tank inside primary containment. At 38 percent power, main turbine vibrations increased above allowable values and the turbine was manually tripped. Following the turbine trip, the reactor unexpectedly automatically tripped on the C steam generator low-low level trip setpoint. Dominion entered this condition into their corrective action program as CR-06-04788. Corrective actions for this issue included plans to conduct an engineering analysis to determine the new steam generator low-low level trip setpoints and revision of the design change notice and the 10 CFR 50.59 screening.

This finding is more than minor because it is associated with the Initiating Events Cornerstone and affects the cornerstone objective to limit the likelihood of those events that upset plant stability. Specifically, an inadequate design change review led to an unanticipated reactor trip. This issue is of very low safety significance because it did not contribute to both the likelihood of a reactor trip and the likelihood that mitigation equipment or functions would not be available.

This finding is related to the cross-cutting aspect of human performance in that Dominions review and decision making process was not effective at identifying possible unintended consequences when making assumptions for a risk significant design change. (Section 4OA3.2)iii

Cornerstone: Mitigating Systems

Unit 2

!

Green.

The inspectors identified a finding when Dominion did not recognize that a portion of the auxiliary feedwater (AFW) discharge header contained air voids after they determined that AFW flow instrumentation was behaving erratically as a result of air in the instrument line. Specifically, Dominion initiated a condition report after identifying that AFW flow instrumentation was air bound but closed out operability concerns based on air only affecting instrumentation and not the potential that air could exist in the discharge portion of the system. As a result,

Dominion did not identify existing voids in AFW discharge piping or assess these air voids for impact on AFW operability. Dominion entered this condition into their corrective action program as CR-06-04677. Corrective actions for this issue included conducting ultrasonic testing of the discharge piping, quantifying the air voids in the system, and evaluating operability of the system with these air voids left in place.

This finding is more than minor because it is associated with the Mitigating Systems Cornerstone and affects the cornerstone objective of ensuring the reliability of systems that respond to initiating events to prevent undesirable consequences. Specifically, Dominion did not investigate or evaluate the existence of air voids in the AFW system discharge piping when air was identified in the system. This finding was determined to be of very low safety significance (Green) because it did not result in a loss of function once the existing air voids were identified and evaluated. This finding is related to the cross-cutting aspect of problem identification and resolution in that Dominion did not fully investigate the existence of air voids in other parts of the AFW system and as a result did not fully evaluate the impact of existing air voids in the AFW system discharge piping. (Section 1R15.1)

Unit 3

!

Green.

The inspectors identified a Green NCV of 10 CFR 50, Appendix B,

Criterion XVI, Corrective Action, for the failure to fully evaluate and correct a significant condition adverse to quality which led to a repeat occurrence of air introduction in the gravity feed boration line. Specifically, following identification and documentation of air in the A gravity feed boration line on September 9, 2004, Dominion did not evaluate and correct the cause which then led to a repeat occurrence of air introduction in the B gravity feed boration line on April 13, 2006. The inspectors determined that the cause of both events was due to an inadequate chemical and volume control system (CVCS) fill and vent procedure. Dominion entered this condition into their corrective action program as CR-06-03730. Corrective actions for this issue included venting the air from the gravity feed boration line and plans to revise the CVCS fill and vent procedure.

iv

This finding is more than minor because it is associated with the Mitigating Systems Cornerstone and affects the cornerstone objective of ensuring the availability of systems that respond to initiating events to prevent undesirable consequences. Specifically, excessive air in the gravity feed lines has the potential to damage the operating charging pump if an emergency boration event were to occur. This finding was determined to be of very low safety significance (Green) since full mitigation credit was given for the availability of redundant emergency boration paths. This finding is related to the cross-cutting aspect of problem identification and resolution in that Dominion did not fully evaluate and correct an identified degraded condition discovered in September 2004, which then recurred in April 2006. (Section 1R04).

Licensee-Identified Violations

None.

v

REPORT DETAILS

Summary of Plant Status

Unit 2 operated at essentially 100 percent power for the duration of the inspection period with the following exceptions. On April 1, 2006, the plant was shutdown after the turbine-driven auxiliary feedwater (TDAFW) pump was determined to be inoperable. The TDAFW pump was repaired and retested on April 7, and a reactor startup commenced on April 9. The reactor was returned to 100 percent power on April 10, 2006.

Unit 3 operated at essentially 100 percent power for the duration of the inspection period.

REACTOR SAFETY

Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity

1R01 Adverse Weather Protection

Seasonal Site Inspection (One Site Sample)

Unit 2 and Unit 3

a. Inspection Scope

The inspectors performed a review of severe weather preparations during the onset of the hurricane season to evaluate the sites readiness for seasonal susceptibilities. The inspectors reviewed Dominions preparations for severe weather and the impact on the protection of safety-related systems, structures and components. The inspection ensured that the selected equipment, instrumentation, and supporting structures were configured in accordance with Dominions procedures and that adequate controls were in place to ensure functionality of the systems. The inspectors reviewed the Unit 2 and Unit 3 Final Safety Analysis Report (FSAR) and Technical Specifications (TS) and compared the analysis with procedure requirements to ascertain that procedures were consistent with the FSAR. The inspectors performed partial walkdowns of the Unit 2 and Unit 3 intake structures, service water systems, intake structure traveling screens and emergency diesel generators to determine the adequacy of equipment protection from the effects of hurricanes. The inspectors verified that operator actions defined in the adverse weather procedures maintained readiness of essential systems and that adequate operator staffing was specified. Documents reviewed during the inspection are listed in the Attachment.

b. Findings

No findings of significance were identified.

1R04 Equipment Alignment

Partial System Walkdowns (71111.04 - Two Unit 2 Samples and Two Unit 3 Samples)

a. Inspection Scope

The inspectors performed four partial system walkdowns during this inspection period.

The inspectors reviewed the documents listed in the Attachment to determine the correct system alignment. The inspectors conducted a walkdown of each system to verify that the critical portions of selected systems were correctly aligned in accordance with these procedures and to identify any discrepancies that may have had an effect on operability. The inspectors verified that equipment alignment problems that could cause initiating events, impact mitigating system availability or function, or affect barrier functions, were identified and resolved. The following systems were reviewed based on their risk significance for the given plant configuration:

Unit 2

• Partial equipment alignment of A and C reactor building closed cooling water (RBCCW) heat exchangers (HXs) with the B RBCCW HX out-of-service, May 9, 2006; and

• Partial equipment alignment of the B emergency diesel generator (EDG) during A EDG maintenance, May 18, 2006.

Unit 3

• Partial equipment alignment of A gravity feed boration line, April 18, 2006; and

• Partial equipment alignment of A service water train during a B service water train outage, May 10, 2006.

b. Findings

Unit 2 No findings of significance were identified.

Unit 3

Introduction.

The inspectors identified a Green non-cited violation (NCV) of 10 CFR 50, Appendix B, Criterion XVI, Corrective Action, for the failure to fully evaluate and correct a significant condition adverse to quality which led to a repeat occurrence of air introduction in the gravity feed boration line. Specifically, following identification and documentation of air in the A gravity feed boration line on September 9, 2004, Dominion did not evaluate and correct the cause which led to a repeat occurrence of air introduction in the B gravity feed boration line on April 18, 2006. The inspectors determined that both events were due to an inadequate chemical and volume control system (CVCS) fill and vent procedure.

Description.

On April 17, 2006, during a routine monthly operational readiness test of the B boric acid transfer pump, Operations observed erratic indications on the pump discharge pressure gage. Operations investigated the following day and determined that approximately 29 liters of air was introduced into the B gravity feed boration line.

Operations determined that the air was introduced following the fill and vent of the B charging pump on April 13, 2006. In accordance with Surveillance Procedure (SP)-3604C.8, Gravity Feed Boration Line Gas Accumulation Monitoring, this amount of air made the B gravity feed line inoperable. Operations entered Technical Requirements Manual (TRM) action statement 3TRM-7.6.1, Safety Grade Cold Shutdown, and vented the B gravity feed boration line to restore operability.

The inspectors reviewed Operating Procedure (OP)-3304A, Charging and Letdown, the control room logs, and associated CRs and technical evaluations. The inspectors identified that a similar event had occurred in September 2004. Specifically, on September 9, 2004, following maintenance on the A charging pump, the CVCS system was filled and vented. Approximately nine hours after restoring the A charging pump to an operable status, an ultrasonic test revealed that piping on the downstream side of the gravity feed boration valve was zero percent full (3.5 liters of air). In accordance with SP-3604C.8, this amount of air made the A gravity feed line inoperable.

Operations entered TRM action statement 3TRM-7.6.1, Safety Grade Cold Shutdown and removed the air by venting the A gravity feed boration line.

The inspectors determined that Dominion did not recognize the September 2004 event as a significant condition adverse to quality. The issue was considered a significant condition adverse to quality since damage to an operating charging pump (a safety-related component) would have occurred during a gravity boration event while the excessive air was in the gravity feed lines. The inspectors determined that the failure to take corrective action to preclude repetition from the September 2004 event led to a repeat occurrence of air introduction in the B gravity feed boration line on April 13, 2006. The inspectors determined that the cause of both events was due to an inadequate CVCS fill and vent procedure. Because the cause of the September 2004 event was similar to the April 2006 event, the inspectors concluded that the April 2006 event was within Dominions ability to foresee and correct, and should have been prevented. The performance issue associated with this finding is that Dominion failed to identify and correct the cause of air introduction into the A gravity feed line in September 2004. This then led to a repeat occurrence of air introduction into the B gravity feed line in April 2006.

Analysis.

This finding is more than minor because it is associated with the Mitigating Systems cornerstone and affects the objective of ensuring the availability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the air volume identified in the boration lines in 2004 and 2006 resulted in their unavailability to perform the intended safety function. The inspectors evaluated this finding in accordance with IMC 0609, Appendix A, Significance Determination of Reactor Inspection Findings for At-Power Situations. The Significance Determination Process (SDP) Phase 1 screening identified that a SDP workbook Phase 2 evaluation was needed because the inoperable B gravity feed line represented a potential loss of safety function of one or more non-technical specification trains of equipment designated as risk-significant per 10 CFR 50.65 for greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. In Phase 2, the inspectors determined that the event of interest was an anticipated transient without scram (ATWS). The gravity boration feed line is referenced in the ATWS emergency operating procedure as a backup method of emergency boration and selected 10 CFR Part 50, Appendix R, scenarios to achieve cold shutdown conditions. Because redundant trains of emergency boration were available, the inspectors determined that full mitigation credit was appropriate and concluded that this finding is of very low safety significance (Green). This finding is related to the cross-cutting aspect of problem identification and resolution in that Dominion did not fully evaluate and correct an identified degraded condition discovered in September 2004, which then recurred in April 2006.

Enforcement.

Code of Federal Regulations 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action, requires, in part, that measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and non-conformances are promptly identified and corrected. In the case of significant conditions adverse to quality, the measures shall assure that the cause of the condition is determined and corrective action taken to preclude repetition. Contrary to the above, following documentation of air introduction into the A gravity feed boration line on September 9, 2004, Dominion did not fully evaluate the cause of this condition. This led to a recurrence of air introduction into the B gravity feed boration line on April 13, 2006. This issue has been entered in Dominions corrective action program as CR 06-03730. Corrective actions for this issue included venting the air from the gravity feed boration line and plans to revise the CVCS fill and vent procedure. This issue is being treated as a non-cited violation consistent with Section VI.A of the Enforcement Policy (NCV 05000423/2006003-01, Did Not Evaluate and Correct a Significant Condition Adverse to Quality Associated with Gravity Feed Boration Lines).

1R05 Fire Protection

Quarterly Sample Review (71111.05Q - Three Unit 2 Samples and Three Unit 3 Samples)

a. Inspection Scope

The inspectors performed six walkdowns of fire protection areas during the inspection period. The inspectors reviewed Dominion's fire protection program to determine the required fire protection design features, fire area boundaries, and combustible loading requirements for the selected areas. The inspectors walked down these areas to assess Dominion's control of transient combustible material and ignition sources. In addition, the inspectors evaluated the material condition and operational status of fire detection and suppression capabilities, fire barriers, and any related compensatory measures. The inspectors then compared the existing conditions of the areas to the fire protection program requirements to ensure that selected program requirements were being met. The inspectors also interviewed fire protection engineers and other Dominion staff, and evaluated the impact of fire suppression systems on adjacent plant areas. Documents reviewed during the inspection are listed in the Attachment. The fire protection areas reviewed included:

Unit 2

• Auxiliary Building Cable Vault, 25'6" Elevation (Fire Area A-24);

• West DC Switchgear Room, 14'6" Elevation (Fire Area A-21); and

• Railroad Bay Area, 14'6" Elevation (Fire Area A-14).

Unit 3

• Cable Spreading Area, 24'6" Elevation (Fire Area CB-8);

• Floor Area, Auxiliary Building, 43'6" Elevation (Fire Area AB-1); and

• Floor Area, Auxiliary Building, 66'6" Elevation Fire Area AB-1).

b. Findings

No findings of significance were identified.

1R06 Flood Protection Measures (71111.06 - One Unit 2 Sample)

Internal Flooding Inspection

a. Inspection Scope

During the week of April 3, 2006, the inspectors reviewed one sample of flood protection measures for equipment in the Unit 2 Auxiliary Building Cable Vault. This review was conducted to evaluate Dominions protection of the enclosed safety-related systems from internal flooding conditions. The inspectors performed a walkdown of the area and reviewed the Final Safety Analysis Report, the internal flooding evaluation, and related documents. The inspectors examined the as-found equipment and conditions to ensure that they remained consistent with those indicated in the design basis documentation, flooding mitigation documents, and risk analysis assumptions. The inspectors also interviewed Dominion engineers and other staff. Documents reviewed during the inspection are listed in the Attachment.

b. Findings

No findings of significance were identified.

1R11 Licensed Operator Requalification Program

Resident Inspector Quarterly Review (71111.11Q - One Unit 2 Sample and One Unit 3 Sample)

a. Inspection Scope

The inspectors observed one sample of Unit 2 licensed operator simulator training on April 12, 2006. The inspectors also observed one sample of Unit 3 licensed operator requalification (operability determination) training on April 21, 2006. The inspectors verified that the training evaluators adequately addressed that the applicable training objectives had been achieved, operator performance was adequate, and evaluators were identifying and documenting crew performance problems. Documents reviewed during the inspection are listed in the Attachment.

b. Findings

No findings of significance were identified.

1R12 Maintenance Effectiveness

Routine Maintenance Effectiveness Inspection (71111.12Q - One Unit 2 Sample and One Unit 3 Sample)

a. Inspection Scope

The inspectors reviewed two samples of Dominion's evaluation of degraded conditions, involving safety-related structures, systems and/or components for maintenance effectiveness during this inspection period. The inspectors reviewed licensee implementation of the Maintenance Rule (MR), 10 CFR 50.65, and verified that the conditions associated with the referenced condition reports (CRs) were appropriately evaluated against applicable MR functional failure criteria as found in licensee scoping documents and procedures. The inspectors also discussed these issues with the system engineers and maintenance rule coordinators to verify that they were appropriately tracked against each system's performance criteria and that the systems were appropriately classified in accordance with MR implementation guidance.

Documents reviewed during the inspection are listed in the Attachment. The following conditions were reviewed:

Unit 2

• Loss of Second Facility of Charging Pumps (CR-06-00243).

Unit 3

• B Residual Heat Removal Flow Control Valve Stroke Failed (CR-06-03350).

b. Findings

No findings of significance were identified.

1R13 Maintenance Risk Assessments and Emergent Work Control (71111.13 - Three Unit 2

Samples and Four Unit 3 Samples)

a. Inspection Scope

The inspectors reviewed seven samples of the adequacy of maintenance risk assessments for emergent and planned activities during the inspection period. The inspectors utilized the Equipment-Out-of-Service quantitative risk assessment tool to evaluate the risk of the plant configurations and compared the results to Dominion's stated risk. The inspectors verified that Dominion entered appropriate risk categories and implemented risk management actions as necessary. Documents reviewed during the inspection are listed in the Attachment. The inspectors verified the conduct and adequacy of scheduled maintenance risk assessments for plant conditions affected by performance of the following maintenance and testing activities:

Unit 2

• Emergent work control during week of April 2, 2006, due to failure of the turbine-driven auxiliary feedwater pump;

• Risk assessment during A EDG two-year overhaul, May 15-20, 2006; and

• Risk assessment during B EDG maintenance, June 1, 2006.

Unit 3

• Risk assessment during turbine-driven auxiliary feedwater pump steam trap maintenance, April 13, 2006;

• Risk assessment due to scheduled AEDG maintenance, April 25, 2006;

• Risk assessment due to containment pressure relay replacement, May 5, 2006; and

• Risk assessment during B EDG sequencer slave relay testing, May 8, 2006.

b. Findings

No findings of significance were identified.

1R14 Operator Performance During Non-Routine Evolutions and Events (71111.14 - One Unit

3 Sample)

a. Inspection Scope

The inspectors reviewed one sample of events that demonstrated personnel performance in coping with non-routine evolutions and transients. The inspectors observed operations in the control room and reviewed applicable technical specifications, operability determination basis documents, and technical evaluations to evaluate the adequacy of Dominions response to this event. The inspectors also verified the event was entered into the corrective action program to resolve identified adverse conditions. Documents reviewed during the inspection are listed in the

.

Unit 3

• On June 30, 2006, with the Unit at 100 percent power, Unit 3 operators questioned whether isolation of room cooling to the A rod control motor control center (MCC) room also affected safety-related MCCs in this room. Operators declared the affected switchgear inoperable and entered Technical Specification 3.8.3.1, Onsite Power Distribution. Engineering personnel reviewed the configuration and established a basis for operability based on existing structural supports, service water cooling margin assuming a maximum leak size for the affecting piping, and ultrasonic examination of upstream and downstream piping.

Operators accepted the reasonable assurance of continued operability (RECO),unisolated service water cooling to the room, and exited the technical specification action statement. The inspectors responded to the site and reviewed the basis of the RECO and the adequacy of operator actions.

b. Findings

No findings of significance were identified.

1R15 Operability Evaluations (71111.15 - Six Unit 2 Samples and Five Unit 3 Samples)

a. Inspection Scope

The inspectors reviewed eleven operability determinations associated with degraded or non-conforming conditions to ensure that operability was justified and that mitigating systems or those affecting barrier integrity remained available and no unrecognized increase in risk had occurred. The inspectors also reviewed compensatory measures to ensure that the measures were in place and were appropriately controlled. The inspectors reviewed licensee performance to ensure all related TS and FSAR requirements were met. Documents reviewed during the inspection are listed in the

. The inspectors reviewed the following degraded or non-conforming conditions:

Unit 2

• Turbine-Driven Auxiliary Feedwater (TDAFW) Pump Vibration in Alert Status (CR-06-03441);

• Air in AFW Discharge Piping (CR-06-03840);

• Instrument Air to AFW Flow Control Valve Bottles (CR-06-01796);

• Charging System Bladder Failure at Reduced Pressure (CR-06-03250);

• Reasonable Expectation of Continued Operability Enclosure Building Filtration System Solenoids Related to NRC Information Notice 88-24 (CR-06-05351);

• Incorrect Wattage DC Lighting and TSAS 3.0.3 Entry (CR-06-05202).

Unit 3

• Charging Pump Cooling System Temperature Control Valve (CR-06-03276);

• Control Building Emergency Air Filtration System Configuration (CR-06-03265);

• TDAFW Header Drain Valve Leaking (CR-06-03578);

• B Train Charging due to Air in B Gravity Boration Line (CR-06-03730);

• B Residual Heat Removal Exchanger Flow Control Valve (CR-06-03350).

b. Findings

Unit 2

===.1

Introduction.

The inspectors identified a finding when Dominion did not recognize that a===

portion of the auxiliary feedwater (AFW) discharge header contained air voids after they determined that AFW flow instrumentation was behaving erratically as a result of air in the instrument line. Specifically, Dominion initiated a condition report after identifying that AFW flow instrumentation was air bound but closed out operability concerns based on air only affecting instrumentation and not the potential that air could exist in the discharge portion of the system.

Description.

On April 18, 2006, Operations determined that the Unit 2 AFW flow instrumentation associated with the #2 steam generator was fluctuating with AFW secured. Indicated AFW flow for the instrument was cycling between 0 and 75 gallons per minute (gpm) from control room, remote shutdown, and primary plant computer indications. Dominion determined that there was no TS required action based on the availability of redundant instrumentation. Dominion initiated a work order to vent the instrumentation but had difficulties establishing flow through the low side instrumentation sensing line. Subsequently, a pressurized water source was used to establish flow through this line. Dominion considered recent maintenance performed on the turbine-driven auxiliary feedwater pump as a possible source for the air in the instrumentation line and focused on how the air affected the flow transmitters. Dominion did not investigate whether air voids were present in AFW system discharge piping and, as a result, did not evaluate the impact of discharge piping air voids on the operability of the system.

On April 24, 2006, the inspectors questioned whether or not Dominion had considered the possibility that air voids could be present in other portions of the AFW system and the subsequent effects on the AFW systems capability to deliver the required flow. On April 25, 2006, Dominion conducted ultrasonic testing on various portions of the AFW system and discovered that two sections of the AFW discharge header contained voiding. Specifically, Dominion determined that a 20 foot AFW discharge piping run for the #2 steam generator was 90 percent flooded (approximately 12.68 cubic feet of air).

In addition, Dominion determined that a 30 foot length of AFW discharge piping run for the #1 steam generator was 95 percent flooded (approximately 0.16 cubic feet of air).

Operations subsequently determined that this amount of air would not affect AFW system operability based on the volume of air identified in the system, the location of the air and relevance to a previously accepted Millstone Unit 3 Technical Evaluation (M3-EV-05-008), ECCS Gas Accumulation in Support of Surveillance. The performance deficiency is that Dominion did not recognize the air binding of the AFW feed flow instrument as an indication of the potential for air in the discharge portion of the system and, as a result, did not identify or evaluate air voids that were located in two sections of discharge piping.

Analysis.

The finding is more than minor because it is associated with the Mitigating Systems Cornerstone and affects the cornerstone objective of ensuring the reliability of systems that respond to initiating events to prevent undesirable consequences. This finding was determined to be of very low safety significance (Green) by using Phase 1 of Inspection Manual Chapter (IMC) 0609, Significance Determination Process.

Specifically, the finding did not result in a loss of function per NRC Part 9900 Technical Guidance, Operability Determination Process for Operability and Functional Assessment and was not related to a seismic, flooding, or severe weather event. This finding is related to the cross-cutting aspect of problem identification and resolution in that Dominion did not fully investigate the existence of air voids in other parts of the AFW system and as a result did not fully evaluate the impact of existing air voids in the AFW system discharge piping.

Enforcement.

No violations of regulatory requirements occurred. On April 18, 2006, Dominion did not recognize air binding of the AFW feed flow instrument as an indication for the potential for air in the discharge portion of the system. As a result, Dominion did not identify or evaluate air voids in two sections of discharge piping until questioned by the inspectors on April 24, 2006. This is considered a finding of very low safety significance (Green). This issue has been entered in Dominions corrective action program as CR-06-05202, CR-06-04677, and CR-06-05318. Corrective actions for this issue included conducting ultrasonic testing of the discharge piping, quantifying the air voids in the system, and evaluating operability of the system with these air voids left in place. Because this finding does not involve a violation of regulatory requirements and has very low significance, it is identified as (FIN 05000336/2006003-02), Did Not Identify or Evaluate Air Voids Located in Auxiliary Feedwater System.

Unit 3 No findings of significance were identified.

1R19 Post-Maintenance Testing (71111.19 - Four Unit 2 Samples and Three Unit 3 Samples)

a. Inspection Scope

The inspectors reviewed seven samples of post-maintenance tests (PMT) during this inspection period. The inspectors reviewed these activities to determine whether the PMT adequately demonstrated that the safety-related function of the equipment was satisfied given the scope of the work specified and that operability of the system was restored. In addition, the inspectors evaluated the applicable test acceptance criteria to verify consistency with the associated design and licensing bases, as well as TS requirements. The inspectors also verified that conditions adverse to quality were entered into the corrective action program for resolution. Documents reviewed during the inspection are listed in the Attachment. The following maintenance activities and their post-maintenance tests were evaluated:

Unit 2

• Adjust Packing on Reactor Coolant System #1 Hot Leg Sample Line Isolation Valve (M2-06-03408);

• Overhaul TDAFW Pump Outboard Mechanical Seal (M2-05-06191);

• TDAFW Pump Outboard Bearing Replacement (M2-06-03091); and

• B Control Room Air Conditioning Fuse Replacement Retest (M2-06-04291).

Unit 3

• Repair Leak on TDAFW Pump Steam Trap (M3-06-04349);

• Replace O-rings/Gaskets for #10 Cylinder Water Jumper on Unit 3 B Emergency Diesel Generator (M3-06-04363); and

• B Residual Heat Removal Heat Exchanger Cooling Outlet Isolation Pilot Replacement and Bettis Actuator Overhaul (M3-04-07920).

b. Findings

No findings of significance were identified.

1R20 Refueling and Outage Activities (71111.20 - One Unit 2 Sample)

a. Inspection Scope

The inspectors reviewed one sample of a forced outage following a Unit 2 shutdown associated with the turbine-driven auxiliary feedwater pump failure on April 1, 2006, for compliance with Technical Specification requirements and approved procedures, conduct of outage risk evaluations, configuration control, and maintenance of key safety functions. Documents reviewed during the inspection are listed in the Attachment.

During this forced outage, the inspectors monitored Dominions control of the outage activities listed below:

• Shutdown risk evaluations;

• Startup scheduling;

• Reactor startup and criticality;

• Plant startup; and

• Power ascension.

b. Findings

No findings of significance were identified.

1R22 Surveillance Testing (71111.22 - Two Unit 2 Samples and Two Unit 3 Samples)

a. Inspection Scope

The inspectors reviewed four samples of surveillance activities to determine whether the testing adequately demonstrated equipment operational readiness and the ability to perform the intended safety-related function. The inspectors attended pre-job briefs, verified that selected prerequisites and precautions were met and that the tests were performed in accordance with the procedural steps. Additionally, the inspectors evaluated the applicable test acceptance criteria to verify consistency with associated design bases, licensing bases, and TS requirements and that the applicable acceptance criteria were satisfied. The inspectors also verified that conditions adverse to quality were entered into the corrective action program for resolution. Documents reviewed during the inspection are listed in the Attachment. The following surveillance activities were evaluated:

Unit 2

• Turbine-Driven Auxiliary Feedwater and Recirculation Check Valve In-service Testing (IST) (SP-2610BO-002); and

• B Emergency Diesel Generator Fast Start, Load Run (SP-2613B).

Unit 3

• Charging Pump Cooling System Valve Operability Test for Temperature Control Valve 37B (SP-3603D.3); and

• A Residual Heat Removal Pump Operational IST (SP-3610A.1).

b. Findings

No findings of significance were identified.

Cornerstone: Emergency Preparedness [EP]

1EP6 Drill Evaluation (71114.06 - One Unit 2 Sample and One Unit 3 Sample)

a. Inspection Scope

The inspectors observed one sample of the conduct of Unit 2 licensed operator simulator training during a drill conducted on April 12, 2006, and one sample of the conduct of Unit 3 licensed operator simulator training on May 30, 2006. The inspectors evaluated the Operations crew activities related to evaluating the scenario and making proper emergency action level classification determinations. Additionally, the inspectors assessed the ability of Dominions evaluators to adequately address operator performance deficiencies identified during the exercise. Documents reviewed during the inspection are listed in the Attachment.

b. Findings

No findings of significance were identified.

OTHER ACTIVITIES

[OA]

4OA1 Performance Indicator (PI) Verification (71151 - Three Unit 2 Samples and Three Unit 3

Samples)

Cornerstone: Initiating Events

The inspectors reviewed six samples of Dominion submittals for the PIs listed below to verify the accuracy of the data reported during that period. The PI definitions and guidance contained in NEI 99-02, Regulatory Assessment Indicator Guidelines, Revision 2, were used to verify the basis for reporting each data element.

Unit 2

• Unplanned Scrams per 7000 Critical Hours;

• Unplanned Scrams with Loss of Normal Heat Removal; and

• Unplanned Power Changes per 7000 Critical Hours.

Unit 3

• Unplanned Scrams per 7000 Critical Hours;

• Unplanned Scrams with Loss of Normal Heat Removal; and

• Unplanned Power Changes per 7000 Critical Hours.

The inspectors reviewed portions of the operations logs and initial PI data developed from monthly operating reports and discussed the methods for compiling and reporting the PIs with cognizant licensing and engineering personnel. The inspectors compared graphical representations from the most recent PI report to the initial data to verify that the data was correctly reflected in the report. Documents reviewed during this inspection are listed in the Attachment.

b. Findings

No findings of significance were identified.

4OA2 Identification and Resolution of Problems

.1 Review of Items Entered into the Corrective Action Program

As required by Inspection Procedure 71152, "Identification and Resolution of Problems",

and in order to help identify repetitive equipment failures or specific human performance issues for followup, the inspectors performed a daily screening of items entered into Dominion's corrective action program. This was accomplished by reviewing the description of each new CR and attending daily management review committee meetings.

.2 Semi-Annual Review to Identify Trends

a. Inspection Scope

The inspectors performed a semi-annual review to identify trends that might indicate the existence of a more significant safety issue. The inspectors reviewed Unit 2 and Unit 3 performance indicator monthly reports, condition reports, system health reports, quality assurance audits, self-assessment reports, maintenance reports, and NRC inspection reports and interviewed key personnel to evaluate if a trend existed.

b. Findings and Observations

Operability Determinations No findings of significance were identified. The inspectors continue to evaluate Dominions improvement initiatives in the area of Operability Determination quality and process implementation. For example, on June 2, 2006, the inspectors reviewed Dominion's response when Operations determined that several non-Appendix R lighting fixtures had higher wattage light bulbs than assumed in the station's DC battery loading calculations. Operations took action to restore operability by opening various breakers associated with the lighting fixtures, thereby, restoring margin to both vital batteries.

Dominion did not consider the action to open the breakers supplying the lighting fixtures as a compensatory measure governed under their Operability Determination process.

The inspectors discussed with Dominion over the next several weeks the basis for why the action should have been considered a compensatory measure until full system qualification is restored. As a result, Dominion entered CR-06-06890, Classification needed on what constitutes compensatory measures in Operability Determination Process into the corrective action program (CAP).

The inspectors have noted some effective corrective actions, particularly in the areas of operations and engineering personnel training. However, the inspectors have determined that sustained performance improvement on the part of both Units needs to be demonstrated in order to evaluate the success of Dominions recent initiatives.

Therefore, the residents will continue to follow these issues, including what constitutes compensatory measures, within the framework of the baseline inspection program and re-visit the Operability Determination trend in subsequent reports.

.3 Annual Sample Review

Operator Work-arounds (One Site Sample)

a. Inspection Scope

The inspectors reviewed the current listing of operator work-arounds for Unit 2 and Unit 3. The review was conducted to verify that Dominion procedures and practices provided necessary guidance to plant personnel, that the cumulative effects of the known operator work-arounds were addressed, and that the overall impact on the affected systems were assessed. The inspectors independently assessed the cumulative impact of known operator work-arounds to determine if they adversely affected the ability of plant operators to implement emergency operating procedures, respond to plant transients, or perform normal functions within the expectations of the established Dominion risk models. In support of this assessment, the inspectors reviewed various condition reports regarding operator work-arounds and verified that work-arounds were being identified, tracked, and resolved in Dominions corrective action program.

b. Findings and Observations

No findings of significance were identified. The inspectors determined that operator work-arounds are adequately classified, tracked, and assessed in accordance with Dominion's procedures.

.4 Cross-References to PI&R Findings Documented Elsewhere in this Report

Section 1R04 describes a finding for the failure to identify and correct the cause of the air introduction into the A boric acid transfer pump gravity feed line in September 2004.

This led to a repeat occurrence of air introduction into the B boric acid transfer pump gravity feed line in April 2006. This finding is related to the cross-cutting aspect of problem identification and resolution in that Dominion did not fully evaluate and correct an identified degraded condition discovered in September 2004, which then recurred in April 2006.

Section 1R15 describes a finding for the failure to adequately investigate and assess air voids in the Auxiliary Feedwater System. This finding is related to the cross-cutting aspect of problem identification and resolution in that Dominion did not fully investigate the existence of air voids in other parts of the AFW system and as a result did not fully evaluate the impact of existing air voids in the AFW system discharge piping.

4OA3 Event Followup (71153 - One Unit 2 Sample and One Unit 3 Sample)

.1 (Closed) LER 05000423/2005-004-00, Pressurizer Spray Nozzle Weld Indications

On December 16, 2005, Dominion reported the discovery of flaws in the pressurizer spray nozzle to safe-end bimetallic region. The inspectors reviewed this LER with its associated condition reports to verify that the cause and corrective actions related to the event described in the LER were adequate. In addition, the inspectors reviewed commitments made with regard to NRC Bulletin 2004-01 to ensure these were appropriately addressed. No findings of significance were identified. This LER is closed.

.2 (Closed) LER 05000423/2005-005-00 and LER 05000423/2005-005-01, Automatic

Reactor Trip of Millstone Unit 3 Due to Low-Low Steam Generator Level

a. Inspection Scope

The inspectors interviewed Dominion personnel and reviewed this LER with its associated condition reports to verify that the root cause and corrective actions related to the event described were adequate.

b. Findings

Introduction.

The inspectors identified a Green NCV of 10 CFR 50, Appendix B, Criterion III, Design Control, for an inadequate design change review for a steam generator low-low water level setpoint modification which led to a reactor trip on December 1, 2005, while conducting a rapid downpower in response to a reactor coolant system (RCS) leak.

Description.

On December 1, 2005, with the plant in Mode 1 at 38 percent power, an automatic reactor trip occurred on a C steam generator low-low level (S/G low-low level) protection signal. At the time of the reactor trip, a rapid downpower to 30 percent was in progress to facilitate a containment entry to locate and repair a RCS leak from the packing of a loop maintenance stop valve that was collected in a drain tank inside primary containment. As turbine load and reactor power were reduced, main turbine vibrations increased above the allowable limits and the main turbine was manually tripped in accordance with procedures. After the turbine was manually tripped, the reactor tripped unexpectedly on C S/G low-low level. At the time of the trip, the reactor protection system S/G low-low level trip setpoint was being maintained at 27 percent versus the original value of 18 percent to address nuclear steam supply system vendor identified S/G level inaccuracies associated with the S/G mid-deck plate differential pressure.

Based on a review of the event, interviews, the LER, associated CRs and other applicable documents, the inspectors determined the design change review in April 2002 for the S/G low-low level setpoint change was inadequate. The review did not take into account the impact of the S/G low-low level setpoint modification on the margin to accommodate S/G level changes due to operational transients. Unit 3 Final Safety Analysis Report, Chapter 15, Section 15.0.1.1, Accident Analysis, states, Condition I occurrences are accommodated with margin between any plant parameter and the value of that parameter which would require either an automatic or manual protective action. The inspectors determined that the Condition I occurrences under consideration for the S/G low-low setpoint change included, in part, operational transients defined in FSAR, Chapter 15 such as step load changes (+/- 10 percent),ramp load changes (up to 5 percent/minute), and load rejection up to and including a design full load rejection transient. The design change review (DCN DM3-00-0077-02, RPS, ESF, AMSAC Low Steam Generator Level Trip Setpoint Change) and associated 10 CFR 50.59 screening concluded that there was no impact on the nuclear steam supply system and balance of plant design bases. The design change had no evaluation or discussion of FSAR, Chapter 15 operational transients. However, as discussed in the LER, the direct cause of the trip was a low-low level in the C S/G that resulted from the shrink in S/G water level created by the manual turbine trip and that operation at the increased S/G low-low level setpoint (27 percent) reduced the margin available to accommodate S/G level transients that occur following a turbine trip at power.

In addition, the inspectors identified that a license amendment should have been submitted for the S/G low-low level setpoint change pursuant to 10 CFR 50.59, Changes, Tests, and Experiments. Specifically, a change to the S/G low-low setpoint Technical Specification (TS 2.2.1, Table 2.2-1, Reactor Trip Instrumentation Trip Setpoints) is required because the actual setting of the nominal trip setpoint (NTS)

(27 percent) is not consistent with the Technical Specification stated value of the NTS (18 percent). The change to the S/G low-low NTS was made in April 2002 with no action identified to initiate a Technical Specification change. The performance deficiency associated with this finding is that Dominion did not conduct an adequate design change review associated with a S/G low-low level trip setpoint modification.

This led to a reduction in automatic protective action margin available to accommodate steam generator level changes for operational transients and resulted in an unintended reactor trip.

Analysis.

This finding is more than minor because it is associated with the Design Control attribute of the Initiating Events cornerstone and affects the objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. The finding is associated with an increase in the likelihood of initiating events in that a reactor trip actually occurred. The inspectors determined that the finding was of very low safety significance (Green)through performance of a Phase 1 SDP in accordance with IMC 0609, Appendix A, Significance Determination of Reactor Inspection Findings for At-Power Situations.

Specifically, this finding did not involve a loss-of-coolant accident or external event initiators or contribute to both the likelihood of a reactor trip and the likelihood that mitigation equipment or functions will not be available. All safety systems performed as designed following the reactor trip. This finding is related to the cross-cutting aspect of human performance in that Dominions review and decision making process was not effective at identifying possible unintended consequences when making assumptions for a risk significant design change.

Enforcement.

Code of Federal Regulations 10 CFR Part 50, Appendix B, Criterion III, Design Control, states, in part, design control measures shall provide for verifying or checking the adequacy of design, such as by the performance of design reviews, by the use of alternate or simplified calculational methods, or by the performance of a suitable testing program. Contrary to this requirement, in April 2002, Dominion did not conduct an adequate design review of the S/G low-low level setpoint modification which led to an unanticipated reactor trip on December 1, 2006. This issue has been entered into Dominions corrective action program as CR-06-04788. Corrective actions for this issue included plans to conduct an engineering analysis to determine new S/G Low-Low level setpoints and revision of the design change notice and the 10 CFR 50.59 screening.

This issue is being treated as a non-cited violation consistent with Section VI.A of the Enforcement Policy (NCV 05000423/2006003-03, Did Not Adequately Evaluate a Reactor Protection System Setpoint Modification).

4OA5 Other Activities

Implementation of Temporary Instruction (TI) 2515/165 - Operational Readiness of Offsite Power and Impact on Plant Risk

a. Inspection Scope

The objective of TI 2515/165, "Operational Readiness of Offsite Power and Impact on Plant Risk," was to gather information to support the assessment of nuclear power plant operational readiness of offsite power systems and impact on plant risk. The inspectors evaluated Dominion procedures against the specific offsite power, risk assessment and system grid reliability requirements of TI 2515/165. They also discussed the attributes with Dominion personnel.

The information gathered while completing this TI was forwarded to the Office of Nuclear Reactor Regulation for further review and evaluation on April 3, 2006.

b. Findings

No findings of significance were identified.

4OA6 Meetings, Including Exit

Integrated Report

Exit Meeting Summary

On July 11, 2006, the resident inspectors presented the overall inspection results to Mr. A. Skip Jordan and other members of his staff, who acknowledged the findings. The inspectors asked Dominion whether any of the material examined during the inspection should be considered proprietary. No proprietary information was identified.

ATTACHMENT:

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee personnel

J. Armstrong, Unit 2 Fire Protection Engineer

B. Bartron, Licensing

B. Burnham, I&C Engineer

G. Closius, Licensing

K. Cortis, AOV Program Coordinator

D. Dodson, Licensing

R. Fuller, Configuration Control

R. Griffin, Director, Nuclear Station Safety and Licensing

T. Ickes, IST Coordinator

A. Jordan, Director, Nuclear Station Operations and Maintenance

M. Kai, Safety Analysis

R. MacManus, Director, Nuclear Engineering

J. Mangeno, Unit 3 Fire Protection Engineer

A. Price, Site Vice President - Millstone

N. Sacco, Configuration Control

J. Semancik, Unit 3 Assistant Operations Manager

NRC personnel

J. C. Benjamin, Resident Inspector, Division of Reactor Projects (DRP)

J. A. Bobiak, Reactor Inspector, Division of Reactor Safety (DRS)

G. Johnson, Reactor Inspector, DRS

S. R. Kennedy, Resident Inspector, DRP

S. M. Schneider, Senior Resident Inspector, DRP

N. S. Sieller, Reactor Engineer, DRP

LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED

Opened and Closed

05000423/2006003-01 NCV Did Not Evaluate and Correct a Significant Condition Adverse to Quality Associated with Gravity Feed Boration Lines (1R04)

05000336/2006003-02 FIN Did Not Identify or Evaluate Air Voids Located in Auxiliary Feedwater System (1R15.1)

05000423/2006003-03 NCV Did Not Adequately Evaluate a Reactor Protection System Setpoint Modification (4OA3.2)

Closed

05000423/2005-004-00 LER Pressurizer Spray Nozzle Weld Indications (4OA3.1)

05000423/2005-005-00, 01 LER Automatic Reactor Trip of Millstone Unit 3 Due to Low-Low Steam Generator Level (4OA3.2)