ML15097A084
| ML15097A084 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 03/31/2015 |
| From: | Stoddard D Dominion, Dominion Nuclear Connecticut |
| To: | Document Control Desk, Office of Nuclear Material Safety and Safeguards |
| References | |
| EA-14-126 | |
| Download: ML15097A084 (6) | |
Text
i~Dominion Dominion Nuclear Connecticut, Inc.
5000 Dominion Boulevard, Glen Allen, VA 23060 Web Address: www.domn.com March 31, 2015 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Serial No.
NSSL/TGC Docket Nos.
License Nos.15-073 R10 50-336/423 DPR-65/NPF-49 DOMINION NUCLEAR CONNECTICUT, INC. (DNC)
MILLSTONE POWER STATION UNITS 2 AND 3 REPLY TO A NOTICE OF VIOLATION EA-14-126 Pursuant to the requirements of 10 CFR 2.201, Dominion Nuclear Connecticut, Inc.
(DNC) herein provides a Reply to a Notice of Violation, EA-14-126, regarding a failure to obtain a license amendment pursuant to 10 CFR 50.90, prior to implementing a change that resulted in more than a minimal increase in the likelihood of occurrence of a malfunction of a system, structure, or component (SSC) important to safety previously evaluated in the Updated Final Safety Evaluation Report (UFSAR). Specifically, DNC allowed a design change to the offsite power system that included the removal of a special protection system known as the severe line outage detection (SLOD) from service without conducting a written evaluation or providing a basis that the change did not require a license amendment in accordance with 10 CFR 50.59.
The attachment provides DNC's reply to thE letter EA-14-126, dated February 10, 2015.
docketed correspondence dated October "Response to an Apparent Violation in NRC 05000423/2014011; EA-14-126."
Notice of Violation as required by NRC In the reply, DNC references previous 14, 2014, DNC Serial Number 14-451 Inspection Report 05000336/2014011 and DNC commits to the plan and schedule as described in the attached Reply to a Notice of Violation, EA-14-126 to submit a license amendment request to the NRC to address this issue.
If you have any questions or require further information, please contact Mr. William D.
Bartron at (860) 444-4301.
Sincerely, Daniel G. Stoddard Senior Vice President - Nuclear Operations
Serial Number 15-073 Docket Nos. 50-336/423 Page 2 of 2
Attachment:
Reply to a Notice of Violation, EA-14-126 Commitments made in this letter: DNC will submit an LAR for MPS2 and MPS3 Final Safety Evaluation Reports (FSARs) to the NRC for approval that describes the basis for MPS's meeting GDC 17 by the end of the second quarter 2015.
cc:
Regional Administrator U.S. Nuclear Regulatory Commission Region I 2100 Renaissance Blvd., Suite 100 King of Prussia, PA 19406-2713 M. C. Thadani Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop 08 B 1 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station
Serial Number 15-073 Docket Nos. 50-336/423 ATTACHMENT REPLY TO A NOTICE OF VIOLATION EA-14-126 DOMINION NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNITS 2 AND 3
Serial Number 15-073 Docket Nos. 50-336/423 Attachment, Page 1 of 3 NOTICE OF VIOLATION During an NRC special inspection conducted between June 2, 2014, and July 15, 2014, which included an on-site inspection as well as an in-office review, for which an exit meeting was conducted on July 15, 2014, a violation of NRC requirements was identified. The violation states:
"Title 10 CFR 50.59, "Changes, Tests, and Experiments," Section (c)(2)(ii) requires, in part, that a licensee shall obtain a license amendment pursuant to 10 CFR 50.90 prior to implementing a proposed change if the change would result in more than a minimal increase in the likelihood of occurrence of a malfunction of a system, structure, or component (SSC) important to safety previously evaluated in the final safety analysis report (as updated).
10 CFR 50.59(d)(1) requires, in part, that a licensee shall maintain records of changes in the facility made pursuant to paragraph (c) of this section.
These records must include a written evaluation which provides the bases for the determination that the change does not require a license amendment pursuant to paragraph (c)(2) of this section.
Contrary to the above, on December 20, 2012, Dominion failed to obtain a license amendment pursuant to 10 CFR 50.90, prior to implementing a change that resulted in more than a minimal increase in the likelihood of occurrence of a malfunction of an SSC important to safety previously evaluated in the UFSAR. Specifically, Dominion allowed a design change to the offsite power system (removal of the severe line outage detection system (SLOD), a system described in the UFSAR), and failed to conduct a written evaluation or provide a basis for the determination that the change did not require a license amendment in accordance with 10 CFR 50.59 (c)(2). The change may have resulted in more than a minimal increase in the likelihood of occurrence of an offsite power malfunction such that the removal of SLOD decreased the reliability of the offsite power system, reduced the defense-in-depth, and disabled an automatic generator rejection function, which protected the offsite power sources during transients caused by grid-related conditions. The removal contributed to the likelihood of a dual-unit trip and loss of offsite power to both units.
This is a Severity Level III violation (Enforcement Policy Section 2.2.2)."
Reply to a Notice of Violation EA-14-126 Pursuant to the requirements of 10 CFR 2.201, Dominion Nuclear Connecticut, Inc.
(DNC) submits the following information in Reply to Notice of Violation EA-14-126.
Serial Number 15-073 Docket Nos. 50-336/423 Attachment, Page 2 of 3
- 1) The reason for the Violation (NOV) or, if contested, the basis for disputing the violation DNC does not contest the violation.
DNC failed to request a license amendment pursuant to 10 CFR 50.90 for removal of SLOD because the need for a 10 CFR 50.59 screen in 2012 was not recognized and the subsequent 10 CFR 50.59 screen was inadequate. When preparing the 10 CFR 50.59 screen, engineering personnel did not consider that the removal of SLOD was an adverse change in the method of meeting General Design Criteria (GDC) 17. Therefore, the screen did not conclude that a 10 CFR 50.59 evaluation and subsequent license amendment request was needed.
The root cause evaluation associated with this violation identified the direct cause as a lack in proficiency and skill in performing 10 CFR 50.59 screens. The root cause was determined to be that continuing training was not adequate to maintain the proficiency and skills for consistent, accurate 10 CFR 50.59 screens.
Corrective actions were taken to address the identified causes.
The complexities associated with the technical issue, multiple responsible entities (the transmission system operator, the transmission system owner, North American Electric Reliability Corporation and DNC) involved in the removal of SLOD, and understanding of the Millstone Power Station (MPS) Unit 2 (MPS2) and Millstone Power Station Unit 3 (MPS3) licensing basis are also relevant to understanding the contributing factors for the violation. During review of this violation, it was determined that DNC's error of not performing a 10 CFR 50.59 evaluation and related failure to request a license amendment occurred during the design development for the removal of SLOD. SLOD removal was conducted by the transmission system owner, Eversource Energy (EE),
formerly known as Northeast Utilities. Most of the removed SLOD hardware was owned and maintained by EE and located offsite on EE property.
During the design development, DNC did not recognize that EE's proposed removal of SLOD resulted in a change in the method of meeting GDC 17 that required DNC to perform a 10 CFR 50.59 evaluation.
- 2) The corrective steps that have been taken and the results achieved After removal of SLOD, and as discussed in the response to the apparent violation associated with this violation (DNC Serial Number 14-451, "Response to an Apparent Violation in NRC Inspection Report 05000336/2014011 and 05000423/2014011; EA 126," dated October 14, 2014), the station configuration was no longer consistent with the method for meeting GDC 17 approved by the NRC at the time of original licensing of MPS3.
As documented in NRC Special Inspection Report 05000336/2014011 and 05000423/2014011, DNC implemented a compensatory measure by issuing an Operations Standing Order that provides interim guidance related to future offsite line outages and plant generation output.
To improve the quality of the 10 CFR 50.59 screens, the training program has been revised to include a discussion of the fundamentals of GDC compliance and the
I Serial Number 15-073 Docket Nos. 50-336/423 Attachment, Page 3 of 3 importance of correctly identifying and reviewing the impacts of design changes upon the design and licensing basis, including the Final Safety Evaluation Report (FSAR).
This revised training is required annually for personnel who perform 10 CFR 50.59 screens. Additionally, personnel who are qualified to perform 10 CFR 50.59 screens have attended refresher training.
A review of the 10 CFR 50.59 screens for FSAR changes initiated within the past three years has been performed to determine whether adequate design and licensing basis reviews were conducted. The review indicates that one 50.59 screen other than the screen performed for SLOD requires further evaluation to determine if corrective action is needed. This condition has been entered into MPS's Corrective Action system.
- 3) The corrective steps that will be taken DNC will submit a License Amendment Request (LAR) that describes the basis for meeting GDC-17. The LAR will propose changes to the FSAR to reflect the currently installed configuration of the offsite power sources, including the modifications that replaced the dual circuit tower design with individual towers and eliminated the SLOD system. In addition, the LAR will likely propose an "allowed outage time" that would be applicable during the periods when a single offsite circuit is not in service. The "allowed outage time" being developed will be proposed in conjunction with appropriate operational limitations when a single offsite circuit is out of service. The proposed "allowed outage time" and associated operational limitations will be designed to minimize the risk to the plant and maintain offsite grid stability when one circuit is out of service due to either an unplanned event or in order to conduct planned maintenance activities on the transmission system. DNC will submit this LAR to the NRC by the end of the second quarter 2015.
- 4) The date when full compliance will be achieved Full compliance will be achieved upon submittal and NRC approval of the LAR.