ML103200194
| ML103200194 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 11/08/2010 |
| From: | Becker J R Pacific Gas & Electric Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| DCL-10-140, OL-DPR-80, OL-DPR-82 | |
| Download: ML103200194 (5) | |
Text
Pacific Gas and Electric Company James R. Becker Diablo Canyon Power Plant Site Vice President Mail Code 104/5/601 P. 0. Box 56 Avila Beach, CA 93424 805.545.3462 November 8, 2010 Internal:
691.3462 Fax: 805.545.6445 PG&E Letter DCL-10-140 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20852 Docket No. 50-275, OL-DPR-80 Docket No. 50-323, OL-DPR-82 Diablo Canyon Units 1 and 2 Response to NRC Letter dated November 5, 2010, Summary of Telephone Conference Call Held on September 30, 2010 Between the U.S. Nuclear Requlatory Commission and Pacific Gas and Electric Company Concerning Request for Additional Information Related to the Diablo Canyon Nuclear Power Plant, Units 1 and 2, License Renewal Application
-Scoping and Screening Dear Commissioners and Staff: By letter dated November 23, 2009, Pacific Gas and Electric Company (PG&E)submitted an application to the U.S. Nuclear Regulatory Commission (NRC) for the renewal of Facility Operating Licenses DPR-80 and DPR-82, for Diablo Canyon Power Plant (DCPP) Units 1 and 2, respectively.
The application included the license renewal application (LRA) and Applicant's Environmental Report -Operating License Renewal Stage.By letter dated November 5, 2010, the NRC staff sent a summary of a telephone conference between the NRC and representatives of PG&E held on September 30, 2010, to obtain clarification on PG&E's response to a request for additional information (RAI) submitted to the NRC in a letter dated August 17, 2010, and September 7, 2010.PG&E's response to the RAI is included in the Enclosure.
PG&E makes no regulatory commitments (as defined in NEI 99-04) in this letter.If you have any questions regarding this response, please contact Mr. Terence L. Grebel, License Renewal Project Manager, at (805) 545-4160.A member of the STARS (Strategic Teaming and Resource Sharing) ALliance Catlaway
- Comanche Peak
- Diablo Canyon a Palo Verde
- San Onofre
- South Texas Project e Wolf Creek A4 3cýCZC Document Control Desk November 8, 2010 Page 2 PG&E Letter DCL-10-140 I declare under penalty of perjury that the foregoing is true and correct.Executed on November 8, 2010.James RBecker Site Vice President TLG/50357602 Enclosure cc: Diablo Distribution cc/enc: Elmo E. Collins, NRC Region IV Regional Administrator Nathanial B. Ferrer, NRC Project Manager, License Renewal Kimberly J. Green, NRC Project Manager, License Renewal Michael S. Peck, NRC Senior Resident Inspector Alan B. Wang, NRC Project Manger, License Renewal A member of the STARS (Strategic Teaming and Resource Sharing) A!liance Callaway
- Comanche Peak
- Diablo Canyon
- Palo Verde
- San Onofre
- South Texas Project
- Wolf Creek Enclosure PG&E Letter DCL-10-140 Page 1 of 3 PG&E Response to NRC Letter dated November 5, 2010, Summary of Telephone Conference Call Held on September 30, 2010, Concerning Responses to Requests for Additional Information (Sets 13 and 18)Related to the Diablo Canyon License Renewal Application RAI 2.3.3.7-3 By letter dated September 7, 2010, the applicant responded to RAI 2.3.3.7-3, and provided a description of the water traps, and indicated that there are not oil filters located in the turbine building.
However, the staff was unclear about a component indicated as an oil filter on license renewal boundary drawing LR-DCPP-25-106725-50.
The staff was also unclear if a failure of the described water traps could affect safety-related equipment.
Discussion:
PG&E agreed to supplement its response to RAI 2.3.3.7-3 to clarify the oil filter on the above license renewal boundary drawing and provide clarification on whether failure of the water traps described above could affect safety-related equipment.
PG&E Response to RAI 2.3.3.7-3 PG&E Letter DCL-1 0-116, dated September 7, 2010, provided detailed information regarding various pressure filled components in the compressed air system. Described in the letter was a justification why these components do not have to be included in scope of license renewal under 10 CFR 54.4(a)(1).
License Renewal Application drawings LR-DCPP-25-106725-50 (location 501-C) and LR-DCPP-25-107725-42 (location 421-C) show oil filters in the instrument air supply portion of the compressed air system. The compressed air system is an oil-free system as it utilizes non-lubricated compressors.
Therefore, these oil filters contain no oil in them. The oil filters were part of the original plant design as a conservative approach if the plant ever was to use lubricated compressors.
These particular oil filters are located on instrument air lines to temperature control valve AXS-1/2-TCV-5003, which automatically varies the steam supply to the supply air heating coils. This portion of the system is hardly used as the purpose of these heating coils is to provide winter heating for personnel comfort. The coils are designed to raise the supply air to a temperature of 701F (Final Safety Analysis Report, Revision 19, Table 9.4-6); however, the room temperature for all rooms in the fuel handling building is normally above this value.The safety-related components that interface with the compressed air system are the air operated valves with Design Class I operators,-
which require instrument quality air to ensure proper operation.
Instrument air is dry because the dewpoint is maintained at Enclosure PG&E Letter DCL-10-140 Page 2 of 3 least 18 0 F below the minimum temperature at any point in the instrument air system.The water traps located in the instrument air lines to the Design Class I operators are small, and activate by opening and spraying the small amount of accumulated liquid directly to the environment.
PG&E Letter DCL-10-116 discusses how structures, systems, and components, in scope of license renewal under 10 CFR 54.4(a)(1), in the vicinity of these water traps are protected from the effects of spray and drip during normal operation or failure of the traps.In the event of water trap failure and loss of instrument air, safety-related air operated valves are designed to fail to their safe condition.
Response to Request for Additional Information 2.3.3.7-2 in PG&E Letter DCL-10-116 discusses the use of the backup air/nitrogen supply system to provide compressed air to safety-related air operated components that are required to perform an active safety-related function after the loss of the compressed air system. Pressure boundary failure of the water trap does not impact the class I backup air systems because of the isolation device at each valve actuator.Therefore, water trap failure does not affect safety-related air operated valves as they fail to their safe condition or have a backup air/nitrogen supply. Furthermore, since the compressed air system is an oil-free system, the oil filters on the instrument air supply lines contain no oil in them.
Enclosure PG&E Letter DCL-10-140 Page 3 of 3 RAI 2.3.3.6-2 and 2.3.3.18-2 By letters dated August 17 and September 7, 2010, the applicant responded to RAIs 2.3.3.6-2 and 2.3.3.18-2, and provided a description of how seismic endpoints were established at various panels. The staff was unclear how the applicant designated the endpoints as base-mounted equipment.
Discussion:
PG&E agreed to supplement its responses to RAts 2.3.3.6-2 and 2.3.3.18-2 to address how endpoints at base-mounted equipment were established.
PG&E Response to RAI 2.3.3.6-2 and 2.3.3.18-2 PG&E Letter DCL-10-116, dated September 7, 2010, discussed the addition of a seismic flag to the containment air sample panel on License Renewal Application (LRA)boundary drawings.
The purpose of this action was to indicate the air sample panel can serve as an anchor point for sample piping attached to it.The structural integrity attached termination flag shown for the sample panel on boundary drawings LR-DCPP-1 1-10711-05 (at location 53-B) and LR-DCPP-1 1-106711-06 (at location 63-B) was removed as it is not needed. All of the affected lines are 1/4-inch tubing lines which, by design, do not continue the structural integrity attached function.
The tubing itself is attached to the walls of rooms and mounting brackets of instrument and sample panels as required by Diablo Canyon Power Plant design specifications (Design Criteria Memorandum (DCM) T-25, Section 2.1.4). The correct termination designations are shown on the revised boundary drawings.On boundary drawings LR-DCPP-23A-1 06723-03 and LR-DCPP-23A-1 077123-03, at location 36-E through C, a terminal component flag was added on revision 2 of these boundary drawings.
The affected lines are tubing and by design do not continue the structural integrity attached function.
This is consistent with NEI 95-10 Appendix F, Section 4.4 b (reference DCM T-25, Section 2.1.4; DCM T-38, Section 4.3.1.1.3).
No change to the LRA is required.