IR 05000317/2006008

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IR 05000317-06-008, 05000318-06-008; Constellation Generation Group, LLC; 07/17/06 - 08/25/06; Calvert Cliffs Nuclear Power Plant, Units 1 and 2; Engineering Design Team Inspection
ML062770113
Person / Time
Site: Calvert Cliffs  Constellation icon.png
Issue date: 10/04/2006
From: Doerflein L
Engineering Region 1 Branch 2
To: Spina J
Calvert Cliffs, Constellation Generation Group
References
IR-06-008
Download: ML062770113 (35)


Text

ber 4, 2006

SUBJECT:

CALVERT CLIFFS NUCLEAR POWER PLANT - NRC COMPONENT DESIGN BASES INSPECTION REPORT 05000317/2006008 AND 05000318/2006008

Dear Mr. Spina:

On August 25, 2006, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Calvert Cliffs Nuclear Power Plant Units 1 and 2. The enclosed inspection report documents the inspection results, which were discussed on August 25, 2006, with Mr. J. Pollock 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.

In conducting the inspection, the team examined the adequacy of selected components and operator actions to mitigate postulated transients, initiating events, and design bases accidents.

The inspection also reviewed Constellations response to selected operating experience issues.

The inspection involved field walkdowns, examination of selected procedures, calculations and records, and interviews with station personnel.

Based on the results of this inspection, no findings of significance were identified.

In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter and its enclosures, 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 the NRCs document system (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Lawrence T. Doerflein, Chief Engineering Branch 2 Division of Reactor Safety Docket Nos. 50-317, 50-318 License Nos. DPR-53, DPR-69 Enclosure: Inspection Report Nos. 05000317/2006008 and 05000318/2006008 w/Attachment: Supplemental Information cc w/encl:

M. J. Wallace, President, Constellation Generation J. M. Heffley, Senior Vice President and Chief Nuclear Officer President, Calvert County Board of Commissioners C. W. Fleming, Senior Counsel, Constellation Generation Group, LLC Director, Nuclear Regulatory Matters R. McLean, Manager, Nuclear Programs K. Burger, Esquire, Maryland People's Counsel State of Maryland (2)

SUMMARY OF FINDINGS

IR 05000317/2006-008, 05000318/2006-008; 07/17/06 - 08/25/06; Calvert Cliffs Nuclear Power

Plant, Units 1 and 2; Engineering Design Team Inspection.

This inspection was conducted by a team of four NRC inspectors and two NRC contractors.

The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 3, dated July 2000.

NRC-Identified and Self-Revealing Findings

None.

Licensee Identified Violations

None.

ii

REPORT DETAILS

REACTOR SAFETY

Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity

1R21 Component Design Bases Inspection (IP 71111.21)

.1 Inspection Sample Selection Process

The team selected risk significant components and operator actions for review using information contained in Calvert Cliffs Probabilistic Risk Analysis (PRA), the U. S.

Nuclear Regulatory Commissions (NRCs) Standardized Plant Analysis Risk (SPAR)model, and the Significance Determination Process (SDP) Risk Informed Inspection Notebook, Revision 2, for the Calvert Cliffs Nuclear Power Plant (CCNPP). In general, this included components and operator actions that had a risk achievement worth (RAW) of greater than two. The components selected were located within both safety related and non-safety related systems and included a variety of components such as electrical buses, pumps, motors, diesel generators, heat exchangers (HXs), tanks, piping and valves.

An initial list, consisting of over 50 components, was created based on risk considerations. The team performed a margin assessment to narrow this list down to 16 components for a detailed design review. This design margin assessment considered original design issues, margin reductions due to modifications, or margin reductions identified as a result of material condition/equipment reliability issues. Issues impacting design margin included failed performance test results, significant corrective action history, repeated maintenance, Maintenance Rule (MR) (a)(1) status, operability reviews for degraded conditions, NRC resident inspector input of problem equipment, system health reports and industry operating experience (OE). Consideration was also given to the uniqueness and complexity of the design and the available defense-in-depth margins. An overall summary of the reviews performed and the specific inspection findings identified are included in the following sections of the report. Specific documents reviewed are listed in the attachment to this report.

.2 Results of Detailed Reviews

.2.1 Detailed Component Design Reviews (16 Samples)

.2.1.1 No. 21 4160 Volt Alternating Current (AC) Safety Bus

a. Inspection Scope

The team reviewed calculations and drawings to determine if the loading of the No. 21 4160Vac vital bus was within equipment ratings. The team reviewed the adequacy and appropriateness of design assumptions and calculations related to motor starting and loading voltages to determine if the voltages across motor terminals, under worst-case motor starting and loading conditions, would remain above the minimum acceptable values. On a sample basis, the team reviewed maintenance and test procedures and acceptance criteria to verify that the No. 21 4160Vac vital bus was capable of supplying the minimum voltage necessary to ensure proper operation of connected equipment during normal and accident conditions. The team reviewed the adequacy of the short circuit ratings of the switchgear and circuit breakers and the adequacy of protective device coordination provided for a selected sample of equipment.

The team reviewed calculations, drawings, and procedures to determine whether undervoltage relay setpoints, load shed schemes, and load sequencing were adequate to assure availability of vital loads within the times assumed in Updated Final Safety Analysis Report (UFSAR) Section 8.3.1.2. The team conducted a walkdown of the 4160Vac vital buses to verify that their material condition, operating environment, and breaker alignments were consistent with the design bases.

b. Findings

No findings of significance were identified.

.2.1.2 No. 22 Component Cooling Water Heat Exchanger

a. Inspection Scope

The team selected the No. 22 component cooling water (CCW) heat exchanger (HX) as a representative sample of the CCW HXs installed in both units. The team evaluated the CCW HX design, maintenance history, and current material condition to assess whether it was capable of removing sufficient heat from the CCW system during normal and accident conditions. The team reviewed the CCW HX vendor manual, CCW system design calculations, and CCW system operating procedures. The team also reviewed condition reports (CRs), work orders, system health reports, maintenance procedures, engineering evaluations, and fouling data trends to assess the effectiveness of preventive and corrective maintenance on the No. 22 CCW HX. In addition, the team interviewed and conducted a walkdown with the CCW system engineer.

b. Findings

No findings of significance were identified.

.2.1.3 No. 2A Emergency Diesel Generator

a. Inspection Scope

The team selected the No. 2A emergency diesel generator (EDG) as a representative sample of the EDGs installed in both units. The team conducted a walkdown of all EDGs and their associated EDG rooms. In addition, the team conducted a detailed walkdown of No. 2A EDG with the EDG system manager. The team reviewed design documents, calculations, in-service test (IST) criteria and results, surveillance testing, vendor manuals, maintenance history, licensing basis documents, and CRs.

b. Findings

No findings of significance were identified.

.2.1.4 Unit 1 No. 23 Control Element Assembly

a. Inspection Scope

The team selected the No. 23 control element assembly (CEA) as a representative sample of the CEAs installed in both units. The team reviewed CRs, operating procedures, surveillance test results, system health reports, and work orders. In addition, the team reviewed Licensee Event Report (LER) 2006-002 and the corrective actions taken as a result of the event. LER 2006-02 described an event which occurred on April 8, 2006, at CCNPP Unit 1 during which the No. 21 CEA was determined to be untrippable due to the introduction of debris into the reactor coolant system. The team reviewed the project plan for the upcoming Unit 2 outage and CCNPPs actions to preclude a repeat occurrence of this event. The team also interviewed the reactor protection system engineer and the engineer responsible for the CEAs and the control element drive mechanisms.

b. Findings

No findings of significance were identified.

.2.1.5 No. 12 Condensate Storage Tank and Auxiliary Feedwater System Suction Piping

a. Inspection Scope

The team walked down accessible portions of the No. 12 condensate storage tank (CST) and auxiliary feedwater (AFW) suction piping including components associated with the CST and enclosure structure, the AFW valve pit, and AFW pump rooms to assess material condition and system alignment. On August 14, the team made a confined space entry to inspect the AFW piping and valves within the AFW valve pit (common to both units). The team reviewed the records of previous excavation, inspection, and repair of portions of currently inaccessible underground AFW piping; pipe support inspection results; design and engineering documentation; calculations and evaluations; records of surveillance and investigation of potential sinkholes in or near system components and equipment; and inspection, testing, and maintenance records related to the CST and suction piping. The review included impact or potential impact of the CST level and nitrogen gas blanket on AFW system flow and performance; available net positive suction head (NPSH); and vortexing and nitrogen ingestion. The team reviewed calculations and evaluations related to pump operation under various transient, accident, and minimum flow conditions.

b. Findings

No findings of significance were identified.

.2.1.6 No. 11A 480 Volt Alternating Current Load Center

a. Inspection Scope

The team reviewed calculations and drawings to determine if the loading of the No. 11A 480Vac vital bus was within equipment ratings. The team reviewed the adequacy and appropriateness of design assumptions and calculations related to motor starting and loading voltages to determine if the voltages across motor terminals, under worst-case motor starting and loading conditions, would remain above the minimum acceptable values. On a sample basis, the team reviewed maintenance and test procedures and acceptance criteria to verify that the No. 11A 480Vac vital bus was capable of supplying the minimum voltage necessary to ensure proper operation of connected equipment during normal and accident conditions. The team reviewed the adequacy of the short circuit ratings of the switchgear and circuit breakers and the adequacy of protective device coordination provided for a selected sample of equipment.

The team reviewed calculations, drawings, and procedures to determine whether undervoltage relay setpoints, load shed schemes, and load sequencing were adequate to assure availability of vital loads within the times assumed in UFSAR Section 8.3.1.2.

The team conducted a walkdown of the 480Vac vital buses to verify that their material condition, operating environment, and breaker alignments were consistent with the design bases.

b. Findings

No findings of significance were identified.

.2.1.7 No. 13 High Pressure Safety Injection Pump

a. Inspection Scope

The team reviewed design and engineering documentation; calculations, evaluations and vendor documentation; and inspection, testing, and maintenance records related to the No. 13 high pressure safety injection (HPSI) pump. The review included system flow and performance; available NPSH; vortexing and air ingestion; calculations and evaluations related to pump operation under various transient, accident, and minimum flow conditions; and suction sources (refueling water tank (RWT) and containment recirculation sump) and level. The team performed detailed walkdowns of selected accessible HPSI components and supporting features to assess material condition and system alignment. The team reviewed pump flow and quarterly surveillance test results completed during the last refueling outage; documentation of maintenance; CRs; system health reports; pump performance trending records; as well as documentation associated with various industry and regulatory notifications. The team also reviewed CCNPPs evaluation of selective oil analysis results associated with the pump and motor.

b. Findings

No findings of significance were identified.

2.1.8 No. 22 Turbine Driven Auxiliary Feedwater Pump

a. Inspection Scope

The team reviewed design and engineering documentation; calculations, evaluations and vendor documentation; and inspection, testing, and maintenance records related to the No. 22 turbine-driven AFW (TDAFW) pump. The review included system flow and performance; NPSH; vortexing and gas ingestion; calculations and evaluations related to pump operation under various transient, accident, and minimum flow conditions; and suction source (CST) and level. The team performed detailed walkdowns of the TDAFW pump and supporting features to assess material condition and system alignment. The team reviewed pump flow and quarterly surveillance test results completed during the last refueling outage; documentation of maintenance; CRs; system health reports; pump performance trending records; as well as documentation associated with various industry and regulatory notifications. The team also reviewed the performance of equipment associated with this pump in relation to motive steam supply (AFW turbine steam admission) and motive steam supply bypass (AFW turbine steam admission bypass) valves, air accumulator sizing and tests, and pump/turbine cooling in the event of loss of all AC power. The review included logic documentation related to the AFW actuation system which provides an actuation signal (open) to the AFW turbine steam admission and turbine steam admission bypass valves and a signal (start) to the motor-driven AFW (MDAFW) pump.

b. Findings

No findings of significance were identified.

.2.1.9 No. 23 Motor Driven Auxiliary Feedwater Pump Motor

a. Inspection Scope

The team selected the No. 23 MDAFW pump motor as a representative sample of the installed MDAFW pump motors in both units. The team conducted a walkdown of the motor and associated pump. In addition, the team reviewed vendor manuals, design changes, apparent cause investigations, engineering evaluations, maintenance history and CRs associated with the pump and motor.

b. Findings

No findings of significance were identified.

.2.1.1 0 2MOV659 High Pressure Safety Injection System Recirculation Valve

a. Inspection Scope

The team reviewed design and engineering documentation; calculations and evaluations; and selective inspection, testing, and maintenance records related to the 2MOV659 HPSI system recirculation valve. The review included calculation of required system pressures under which the valve must perform its safety function, required valve performance, and valve test results. The team walked down accessible portions of the HPSI system to assess material condition and system alignment. The team reviewed system health reports; documentation associated with various industry and regulatory notifications; and HPSI system CRs. The team also reviewed logic documentation related to the recirculation actuation signal (RAS) which provides an actuation signal (close) to 2MOV659.

b. Findings

No findings of significance were identified.

.2.1.1 1 No. 11 Emergency Core Cooling System Pump Room Cooler

a. Inspection Scope

The team selected the No. 11 emergency core cooling system (ECCS) pump room cooler as a representative sample of the ECCS pump room coolers. Each ECCS pump room has a single room cooler cooled by the saltwater (SW) system. The failure of a room cooler could prevent adequate heat removal from the associated ECCS pump room and result in the loss of safety function of the associated ECCS pump train. The team conducted a walkdown of the No. 11 ECCS pump room cooler with the ventilation system manager; and reviewed vendor manuals, design calculations, engineering evaluations, maintenance history, and CRs.

b. Findings

No findings of significance were identified.

.2.1.1 2 1CV4521 Steam Generator Block Valve

a. Inspection Scope

The team reviewed design and engineering documentation, calculations, evaluations, and testing records related to the 1CV4521 steam generator (SG) block valve. The review included calculation of required system pressures under which the air operated block valve must perform its safety function, required valve performance, associated air accumulator sizing and tests, and valve test results. The team walked down 1CV4521 and accessible portions of its supporting features to assess material condition and system alignment. The team reviewed system health reports and CRs associated with the valve. The team also reviewed logic documentation related to the AFW actuation system (AFAS) which provides an actuation block signal (close) to 1CV4521.

b. Findings

No findings of significance were identified.

.2.1.1 3 No. 22 125 Volt Direct Current Class 1E Station Battery

a. Inspection Scope

The team reviewed the station battery calculations to verify that the battery sizing would satisfy the requirements at the loads and that the minimum possible voltage was adequate for postulated loading scenarios. Specifically, the evaluation focused on verifying that the battery and battery chargers were adequately sized to supply the design duty cycle of the 125 Vdc system for both the loss of offsite power/loss of coolant accident (LOOP/LOCA) and station blackout (SBO) loading scenarios, and that adequate voltage would remain available for the individual load devices required to operate during a four-hour SBO coping duration. In addition, the team conducted a walkdown to visually inspect the physical/material condition of the battery and battery chargers and confirm that the battery room temperatures were within specified design temperature ranges. During the walkdown, the team visually inspected No. 22 battery for signs of degradation such as excessive terminal corrosion and electrolyte leaks. The team verified that the battery chargers were energized with acceptable indicated voltage and current present. The team reviewed battery surveillance results to verify that applicable technical specification (TS) specified acceptance criteria and frequency requirements were met.

b. Findings

No findings of significance were identified.

.2.1.1 4 Unit 2 Switchgear Heating Ventilation and Air Conditioning System

a. Inspection Scope

The team selected the Unit 2 switchgear heating, ventilation and air conditioning (HVAC)system as a representative sample of the switchgear HVAC systems. The failure of a switchgear HVAC system may result in the loss of safety function of the associated switchgear under design basis conditions. The team conducted a walkdown of the Unit 2 switchgear HVAC system; and reviewed vendor manuals, maintenance history, design calculations, engineering evaluations, design changes, and CRs.

b. Findings

No findings of significance were identified.

.2.1.1 5 No. 11 Saltwater Cooling Pump

a. Inspection Scope

The team selected the No. 11 saltwater cooling (SW) pump as a representative sample of the SW pumps installed in both units. The team reviewed the system design basis flow and NPSH calculations related to pump operation under various transient and accident conditions. The team reviewed recent pump test results, SW CRs, SW intake silt surveys and trending data, and SW system maintenance history. The team conducted walkdowns of all six SW pumps (three per unit), the SW sluice gates, and the SW intake structure and traveling screens to assess material condition and readiness.

In addition, the team conducted a walkdown of the No. 11 SW pump with the SW system engineer.

b. Findings

No findings of significance were identified.

2.1.16 No. 11A Service Water Heat Exchanger Inlet Strainer

a. Inspection Scope

The team selected the No. 11A service water (SRW) HX inlet strainer as a representative sample of the SRW HX inlet strainers installed in both units. The team conducted a walkdown of the No. 11A SRW HX and had detailed discussions with the SW and SRW system engineers. The team observed portions of two SRW HX internal inspection and cleaning preventive maintenance (PM) activities. In addition, the team reviewed vendor manuals, operating procedures, maintenance history, design changes, and CRs.

b. Findings

No findings of significance were identified.

.2.2 Review of Low Margin Operator Actions (4 Samples)

The team performed a margin assessment of expected operator actions, and selected a sample of operator actions for detailed review based upon risk significance and time dependency of the actions. The operator actions were selected from PRA rankings of human action importance based on risk reduction worth (RRW) values and other PRA insights.

Considerations in the review process included the following factors:

  • Environmental conditions or restrictions for performing the actions;
  • Personnel access to equipment;
  • Plant procedures that address the actions;
  • Need for additional personnel or equipment;
  • Information available for diagnosing conditions and initiating actions;
  • Ability of operator to recover from errors while performing a task;
  • Consequences of failure to complete actions;
  • Time to complete actions; and
  • Task included in the Systematic Approach to Training (SAT) based training program and trained on.

The selected operator actions were generally characterized as having one or more of the following attributes:

  • Low margin between the time required and time available to perform the actions;
  • Reliability or redundancy of the components associated with the actions;
  • Complexity of the actions; and
  • Procedure or training challenges that may impact the operators' ability to perform the actions.

.2.2.1 Restore Power to a Safety Related 4 KV Bus

a. Inspection Scope

Following a LOOP with several equipment failures (BHEC4A Rev. 1), the crew has 45 minutes to locally prelube, start, and load the 0C diesel generator (DG) onto the 4 kV bus. The team reviewed task lists, the task-to-training matrix and training materials to ensure that the operator actions were included in their SAT based training program.

The team discussed the operator actions with five NRC licensed operators. The team reviewed drawings and procedures and conducted a plant walkdown to assess the capability of performing these actions. The team observed four crews in evaluated simulator scenarios restore power to a safety related 4 kV bus with the 0C DG. The team also reviewed training performance data and corrective actions reports.

b. Findings

No findings of significance were identified.

.2.2.2 Cross Connect Unit 1 AFW Pump to Supply Unit 2

a. Inspection Scope

In the PRA sequence described in training event BHEFIV Rev. 1, it is assumed that all 3 of the affected units AFW pumps fail and the crew must cross connect the other units AFW pump to supply AFW to the affected unit within 45 minutes. The team reviewed task lists, the task-to-training matrix and training materials to ensure that the operator actions were included in their SAT based training program. The team discussed the operator actions with five NRC licensed operators. The team reviewed drawings and procedures and conducted a plant walkdown to assess the capability of performing these actions.

b. Findings

No findings of significance were identified.

.2.2.3 Initiate Once Through Core Cooling

a. Inspection Scope

In the PRA sequence described in training event BHEOTA Rev. 1, the crew must initiate once through core cooling (OTCC) within 5 minutes of when the SG level reaches -350 inches and there is no feedwater flow available to the SGs. The team reviewed tasks lists, the task-to-training matrix and training materials to ensure that the operator actions were included in their SAT based training program. The team discussed the operator actions with five NRC licensed operators. The team reviewed drawings and procedures to assess the capability of performing these actions. The team observed two crews in evaluated simulator scenarios to verify their capability to initiate OTCC within the five minute time limit.

b. Findings

No findings of significance were identified.

.2.2.4 Establish Long Term Auxiliary Feedwater Flow

a. Inspection Scope

In the PRA sequence described in training event BHEF3X Rev. 2, the crew must align the No. 11 CST to supply Unit 1 and the No. 21 CST to supply Unit 2 within 50 minutes to prevent AFW pump failure due to cavitation. The team reviewed task lists, the task-to-training matrix and training materials to ensure that the operator actions were included in their SAT based training program. The team discussed the operator actions with five NRC licensed operators. The team reviewed drawings and procedures and conducted a plant walkdown to assess the capability of performing these actions.

b. Findings

No findings of significance were identified.

.2.3 Review of Industry Operating Experience and Generic Issues (5 Samples)

a. Inspection Scope

The team reviewed selected operating experience (OE) issues that had occurred at domestic and foreign nuclear facilities for applicability at CCNPP. The team performed an independent applicability review and selected issues with apparent applicability to Calvert Cliffs for a detailed review to verify that the licensee had taken appropriate actions. The team performed a detailed review of the following OE issues; documents reviewed for these issues are listed in the attachment to this report.

.2.3.1 Grid Reliability and Impact on Plant Risk and Operability of Offsite Power

The team reviewed the applicability and disposition of grid reliability and operability of offsite power described in NRC Generic Letter (GL) 2006-02. The purpose of GL 2006-02 was to determine if compliance was being maintained with NRC regulatory requirements governing electric power sources and associated personnel training. The team selected this OE item for detailed review because grid reliability remains an important issue as licensees add new generation to the grid. The detailed review assessed CCNPPs protocols with the transmission system provider and offsite power restoration procedures using NRC Regulatory Guide 1.155, Station Blackout, Section 2.

.2.3.2 Operational Challenges During a Dual Unit Transient

At the time of the event described in NRC Information Notice (IN) 93-44, the licensees staffing was the minimum allowed by TSs. This complicated response and recovery due to the lack of enough licensed operators to perform the necessary actions. In addition, the licensees training was conducted with two licensed operators, so the crew configuration during the event was not as well-staffed as in training.

The Calvert Cliffs facility had the same potential staffing problem for coping with a dual unit event. The team reviewed CCNPPs response to NRC IN 93-44 to ensure that enough operators would be on shift to handle dual unit events. The team reviewed CCNPPs procedures and shift staffing, online and during simulator training.

.2.3.3 Vibration-Induced Degradation of Butterfly Valves

The team reviewed the applicability and disposition of NRC IN 2005-23, Vibration-Induced Degradation of Butterfly Valves. IN 2005-23 concerned the degradation of butterfly valves supplied by Fisher Controls and other manufacturers. The team reviewed CCNPPs evaluation addressing the issues raised in IN 2005-23 and CCNPPs butterfly valve maintenance procedures. In addition, the team discussed butterfly valve condition and maintenance with the engineer responsible for addressing the Information Notice.

.2.3.4 Flow Accelerated Corrosion

The team reviewed the applicability and disposition of NRC IN 99-019, Rupture of the Shell Side of a Feedwater Heater at Point Beach Nuclear Plant. The team reviewed CCNPPs current and revised programs that monitor material condition of HXs and piping systems. The team interviewed the Flow Accelerated Corrosion (FAC) Program manager concerning use of industry OE and the implementation of the current inspection program. The team reviewed OE notifications generated as a result of CCNPPs FAC program, and viewed pictures and videos of inspections conducted on both units.

.2.3.5 Potential Damage to Redundant Safety Related Equipment Due to Internal Flooding

The team reviewed the applicability and disposition of NRC IN 83-44 (Supplement 1),

Potential Damage to Redundant Safety Equipment as a Result of Backflow Through the Equipment and Floor Drain System; and NRC IN 2005-30, Safe Shutdown Potentially Challenged By Unanalyzed Internal Flooding Events and Inadequate Design. At the Kewaunee Power Station, multiple trains of safety-related systems necessary for safe-shutdown (e.g., AFW, EDGs, and electrical distribution switchgear) were located at the same elevation and immediately adjacent to the turbine building (TB) basement. Water from a TB flood could have flowed into these spaces through non-watertight doors and through the floor drain system, which consisted of an open pipe connecting the spaces to the TB sump. The team selected this OE sample based on the risk significance of the Kewaunee internal flooding concern and potential vulnerabilities inherent in the plant layout of the Calvert Cliffs units.

The team reviewed plant drawings, PM and corrective maintenance work orders, CRs, internal flooding calculations and evaluations, system operating and alarm response procedures, and plant modifications. The team also performed numerous detailed walkdowns of the following areas at both units: EDG rooms, SW and circulating water pump rooms, SRW pump rooms, battery and switchgear rooms, ECCS pump rooms, radiation exhaust ventilation equipment rooms, and TDAFW pump rooms. The team performed the detailed reviews and walkdowns to ensure that CCNPP implemented and maintained adequate flood barriers; appropriate administrative controls and procedures; properly functioning sump pumps, check valves, drains, and level instruments; and adequate maintenance practices. The team also observed several related maintenance activities, including SRW HX cleaning/flushing and SRW pump room drain snaking/cleaning.

b. Findings

No findings of significance were identified.

OTHER ACTIVITIES

4OA2 Problem Identification and Resolution

a. Inspection Scope

The team reviewed a sample of problems that CCNPP personnel identified and entered into their corrective action program. The team reviewed these issues to verify an appropriate threshold for identifying issues and to evaluate the effectiveness of corrective actions related to design and qualification issues. In addition, the team reviewed CRs written on NRC-identified issues during the inspection to verify adequate problem identification and incorporation of the problem into the corrective action system.

The specific corrective action documents that were sampled and reviewed by the team are listed in the attachment to this report.

b. Findings

No findings of significance were identified.

4OA6 Meetings, including Exit

On August 25, 2006, the team presented the inspection results to Mr. J. Pollock and other members of Constellation management. The team verified that no proprietary information is documented in the report.

ATTACHMENT

SUPPLEMENTAL INFORMATION

KEY POINTS OF CONTACT

Licensee Personnel

R. Bleacher Reactor Operator Technical Writer

J. Boggs Engineer, Design Engineering
R. Cameron Engineering Analyst, Equipment Reliability
G. Dare Engineering Analyst, System Engineering

S. Dean Assistant Operations Manager

C. Dobry Senior Engineer, System Engineering
A. Drake Mechanical Engineering Consultant, Design Engineering

B. Dyer Supervisor Maintenance Services

P. Fatka Senior Engineer, System Engineering
M. Flaherty Manager, Engineering Services
T. Giles Engineering Analyst, Engineering Programs
J. GineÑ Mechanical Engineering Consultant, System Engineering
A. Henni Mechanical Engineering Consultant, Design Engineering
T. Konerth Principle Engineer, CCNPP Projects
K. Lebarron Engineering Analyst, System Engineering
D. Lenker Principle Engineer, Design Engineering
M. Lewis Mechanical Engineering Consultant, System Engineering
S. Loeper Mechanical Engineering Consultant, System Engineering
D. Murphy Senior Engineer, System Engineering

J. Pollock Plant General Manager

K. Robinson General Supervisor, Design Engineering
B. Scott Principle Engineer, Design Engineering
A. Simpson Engineering Consultant, Licensing
R. Stark E&C Engineering Consultant, Design Engineering
R. Stattel I&C Engineering Consultant, System Engineering
J. Stone Principle Engineer, CGG Nuclear PRA
V. Trojan Senior Engineer, System Engineering
L. Williams Senior Engineering Analyst, System Engineering

J. Wilson Control room Supervisor

J. Wynn Senior Engineer, System Engineering

NRC Personnel

J. Giessner Senior Resident Inspector

M. Davis Resident Inspector

W. Cook Senior Reactor Analyst

LIST OF ITEMS

OPENED, CLOSED AND DISCUSSED

Open and

Closed

None

LIST OF DOCUMENTS REVIEWED