IR 05000423/2005014
| ML053000516 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 10/27/2005 |
| From: | Doerflein L Engineering Region 1 Branch 2 |
| To: | Christian D Dominion Nuclear Connecticut, Dominion Resources |
| References | |
| IR-05-014 | |
| Download: ML053000516 (17) | |
Text
October 27, 2005
SUBJECT:
MILLSTONE POWER STATION UNIT 3 - NRC SAFETY SYSTEM DESIGN AND PERFORMANCE CAPABILITY INSPECTION REPORT 05000423/2005014
Dear Mr. Christian:
On September 16, 2005, the U.S. Nuclear Regulatory Commission (NRC) completed a safety system and design and performance capability team inspection at your Millstone Power Station Unit 3 facility. The enclosed inspection report documents the inspection findings, which were discussed on September 16, 2005, with Mr. Steven Scace 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 inspection team reviewed selected procedures and records, observed activities, and interviewed personnel.
Based on the results of the inspection, no findings of significance were identified.
In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter and its enclosure 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/
Lawrence T. Doerflein, Chief Engineering Branch 2 Division of Reactor Safety Docket No.
50-423 License No.
NPF-49 Enclosure:
NRC Inspection Report 05000423/2005014 w/Attachment: Supplemental Information
Mr.
SUMMARY OF FINDINGS
IR 05000423/2005014; 08/29-09/02/2005 and 09/12-09/16/2005; Millstone Power Station
Unit 3; Engineering Team Inspection.
This inspection was conducted by five inspectors from the NRCs Region I office and a NRC contractor. No findings of significance were identified. 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.
NRC-Identified and Self-Revealing Findings
None
Licensee-Identified Violations
None
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Mitigating Systems and Barrier Integrity
==1R21 Safety System Design and Performance Capability (SSD&PC) (IP 71111.21) A.
Inspection Basis==
The NRC team performed an inspection to verify that selected safety systems would achieve their design and performance capability. The team reviewed the licensee's programs for maintaining the capability of the selected safety systems to perform their safety functions. The team also reviewed nonsafety-related structures, systems and components that provide functions required to support the selected systems safety functions.
The team used information derived from the licensees and NRCs probabilistic risk analysis models to identify systems in the mitigating system and barrier integrity cornerstones making significant contribution to the dominant accident sequences.
Specifically, the inspection reviewed the functional requirements and system interactions for the accident sequence: Stuck Open Relief Valve - Block Valve - High Pressure Injection - Direct Injection, taken from the Risk-Informed Inspection Notebook for Millstone Nuclear Power Station Unit 3 (Revision 1). The team also considered the results of previous SSD&PC inspections as well as operational experience in selecting the systems and components for review. Based on the above, the team selected portions of the high pressure safety injection (HPSI) system, recirculation spray system (RSS), and the residual heat removal (RHR) system for review.
The inspection included review and examination of support systems, such as electrical power and instrumentation. The team assessed the adequacy of calculations used to support functional requirements, analyses and tests that resulted in confirmation of these requirements, and engineering processes used to support the analysis and tests for normal, abnormal, and accident conditions. Acceptance criteria utilized by the NRC inspection team included NRC regulations, the technical specifications, the Updated Final Safety Analysis Report (UFSAR), and industry codes and standards. The team also assessed the licensees ability to monitor the system for age-related degradation that could result in the system failing to fulfill its design requirement. A complete list of documents reviewed is included in the attachment to this report.
B.
System Needs
a. Inspection Scope
The NRC team inspected selected attributes of the systems and support systems:
Process Medium, Energy Sources, Controls, Operator Actions, and Heat Removal. The team verified the selected attributes met the requirements and design basis specifications identified in the UFSAR, technical specifications, licensee commitments, design basis documents, vender technical manuals and plant drawings. A complete list of documents reviewed is included in the attachment.
b. Findings
No findings of significance were identified.
C.
System Condition and Capability
a. Inspection Scope
The NRC team inspected the configuration of the selected systems as installed and the operation, design, and testing of the selected systems. The team verified the selected attributes met the requirements and design basis specifications contained in the UFSAR, technical specifications, design basis documents, vender technical manuals, calculations and plant drawings. A complete list of documents reviewed is included in the attachment to this report. The attributes were verified to meet system requirements as described below:
Installed Configuration. The team confirmed the installed configuration of the systems were in agreement with design basis assumptions. For components where the installed configuration was not in agreement with design basis assumptions the team determined there was remediation such as a corrective action, compensatory action, or supporting calculation. The team confirmed the configuration of the systems by walking down accessible portions of the systems. The walkdowns focused on the installation and configuration of piping and instruments; component material condition; licensee identified deficiencies; the susceptibility to environmental impact such as fire or flooding; physical separation of redundant trains; and resilience to seismic events. The team compared their observations of the systems with the design and licensing bases to assure that the system would be capable of functioning during accident conditions. The team evaluated whether the licensee had identified system deficiencies and entered them into the corrective action program.
Operation. The team reviewed operator actions in selected procedures related to the accident sequence to confirm the operators were able to perform the actions called for in the procedure and had access and tools where necessary to accomplish the actions given credit in the design basis. The team reviewed the selected accident sequence by running the sequence on the simulator using various procedures. The team verified that the performance of operations procedures was consistent with the design and licensing basis.
The team reviewed the operating, alarm response, and emergency operating procedures (EOPs) applicable to the power-operated relief valve (PORV), recirculation spray, safety injection, charging, and residual heat removal systems during the evolutions of reactor trip, safety injection, loss of coolant, cold leg recirculation, and post-LOCA cooldown and depressurization. This review addressed the accuracy of the procedures, consistency with design drawings and UFSAR, and ability to address various component failures and operational errors. The team observed licensed operators during a simulator scenario of their annual requalification examination, in which a PORV stuck open and could not be blocked, to verify that indications, alarms, and procedures supported the prompt identification of the problem and enabled appropriate operator responses.
On the simulator the team evaluated the ability of the EOPs to address various simulated equipment failures and operational errors applicable to a stuck open PORV, high pressure injection failures, and direct injection of the recirculation spray system, including containment sump clogging, inability to rapidly depressurize, pump failures, and improper valve positions. The team also confirmed that sufficient instrumentation existed to monitor automatic system operation and to enable operator responses.
Design. The team reviewed the mechanical, electrical, and instrumentation design of the systems to verify the systems would function as required under design conditions.
The review included the design basis, design changes, design assumptions, calculations, boundary conditions, and a review of modifications. Instrumentation was reviewed to verify set points based on the required equipment function. The inspectors performed a number of independent calculations and analyses in several areas to verify the appropriateness of the design values.
Testing. The team reviewed records of selected periodic testing including Inservice Testing (IST), post-maintenance tests and calibration procedures. The team verified the results obtained by system and component testing adequately demonstrated that the systems met operability requirements. The test results were compared against system calculations, drawings, and procedures. Test results were also reviewed to ensure automatic initiations occurred within required times and that testing was consistent with design basis information.
b. Findings
No findings of significance were identified.
D.
System Components
a. Inspection Scope
The inspectors selected the HPSI pumps and containment sump instrumentation to ensure equipment at the component level met design requirements. The inspectors inspected the components for degradation, environmental qualification, as-installed configuration and operating experience. The team verified the attributes met the requirements and design basis specifications identified in the UFSAR, technical specifications, design basis documents, vender technical manuals, calculations and plant drawings. A complete list of documents reviewed is included in the attachment to this report.
b. Findings
No findings of significance were identified.
OTHER ACTIVITIES (OA)
4OA2 Problem Identification and Resolution
a. Inspection Scope
The team reviewed a sample of system problems that were identified by the licensee and entered into the 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 or qualification issues. In addition, condition reports written on issues identified during the inspection were reviewed 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
The lead inspector presented the inspection results on September 16, 2005, to Mr. Steven Scace and other members of the licensees staff. The inspection team verified this inspection report does not contain proprietary information.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- S. E. Scace, Director - Safety and Licensing
- P. E. Grossman, Manager - Nuclear Engineering
- D. A. Aube, Supervisor - Electrical/I&C Systems and Standards
- P. F. LHeureux, Supervisor - Mechanical Systems and Standards
- W. D. Barton, Licensing
- G. J. Closius, Licensing
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
None