ML102390155
| ML102390155 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 09/15/2010 |
| From: | Ferrer N License Renewal Projects Branch 2 |
| To: | Pacific Gas & Electric Co |
| Ferrer, N B, NRR/DLR, 415-1045 | |
| References | |
| Download: ML102390155 (8) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 15, 2010 LICENSEE: Pacific Gas and Electric Company FACILITY: Diablo Canyon Nuclear Power Plant, Units 1 and 2
SUBJECT:
SUMMARY
OF TELEPHONE CONFERENCE CALL HELD ON AUGUST 12, 2010, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND PACIFIC GAS AND ELECTRIC COMPANY CONCERNING RESPONSES TO REQUESTS FOR ADDITIONAL INFORMATION RELATED TO THE DIABLO CANYON NUCLEAR POWER PLANT, UNITS 1 AND 2, LICENSE RENEWAL APPLICA TION The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Pacific Gas and Electric Company (PG&E or the applicant) held a telephone conference call on August 12, 2010, to obtain clarification on the applicant's response to request for additional information (RAI) regarding the Diablo Canyon Nuclear Power Plant license renewal application.
By letter dated July 19, 2010, PG&E sent the staff a response to RAlletter dated June 21,2010, regarding aging management programs. The staff reviewed the information contained therein, and requested a telephone conference call. The telephone conference call was useful in clarifying the intent of PG&E's response. Enclosure 1 provides a listing of the participants. provides discussions on RAI responses for which the staff requested clarification.
PG&E will submit supplemental responses, as necessary, within 30 days of the issuance of this summary. Follow-up RAls, determined to be necessary, will be issued separately by a formal letter.
The applicant had an opportunity to comment on this summary.
Nathaniel Ferrer, Project Manager Projects Branch 2 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-275 and 50-323
Enclosures:
As stated cc w/encls: Distribution via Listserv
TELEPHONE CONFERENCE CALL DIABLO CANYON NUCLEAR POWER PLANT, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION LIST OF PARTICIPANTS AUGUST 12, 2010 PARTICIPANTS AFFILIATIONS Nate Ferrer U.S. Nuclear Regulatory Commission (NRC)
Abdul Sheik NRC Bryce Lehman NRC Dan Naus Oak Ridge National Laboratory (ORNL)
Barry Oland ORNL Terry Grebel Pacific Gas and Electric Company (PG&E)
Philippe Soenen PG&E Gary Porter PG&E Rob O'Sullivan PG&E Kyle Duke PG&E ENCLOSURE 1
Diablo Canyon Nuclear Power Plant, Units 1 and 2 License Renewal Application Request for Additional Information (Set 5)
Aging Management Programs RAI 82.1.28-1 In its July 19, 2010, response to request for additional information (RAI) 82.1.28-1, the applicant indicated that procedure N DE VT 3C-1 has been revised. However, the staff had the following observations:
- 1. The staff was unclear how the revised sections of procedure NDE VT 3C-1 would preclude any confusion as to what is acceptable under design basis versus acceptability of continued operation by removing the third tier criteria from the procedure.
Discussion:
Pacific Gas and Electric Company (PG&E) agreed to make the revised procedure available for the staff to audit.
- 2. The staff was unclear if calculation 2305C, which still has discussion and evaluation for third tier criteria, would be revised.
Discussion:
The staff will issue a follow-up RAI to determine if or how calculation 2305C would be affected.
RAI82.1.32-1 In its July 19,2010, response to RAI 82.1.32-1, the applicant provided a comparison of Diablo Canyon Nuclear Power Plant's (DCPPs) condition classification categories with ACI 349.3R evaluation criteria. However, the staff was unclear as to whether DCPPs condition classification involved any quantitative criteria, or whether it was all qualitative and based on the judgment of the responsible engineer.
Discussion:
The staff will issue a follow-up RAI to clarify whether quantitative criteria are used in the condition classifications.
RAI 82.1.32-2 In its July 19, 2010, response to RAI 82.1.32-2, the applicant indicated they have a ten year frequency of inspection of structures. The applicant states that DCPP procedures consider the ENCLOSURE 2
-2 guidance of ACI 349.3R-96 and establish frequencies based on aggressiveness of environmental conditions and physical conditions of the plant structures. However, the staff is unclear how guidance provided in Table 6.1 of ACI 349.3R has been used in developing the frequency of inspection of structures.
Discussion:
The staff will issue a follow-up RAI to clarify how the applicant developed the inspection frequency of structures.
RAI 82.1.32-4 In its July 19, 2010, response to RAI 82.1.32-4, the applicant provided details of the minor leak from the Unit 2 spent fuel pool and associated inspections and analyses. However, the staff made the following observations:
- 1. The staff was unclear if the frequency for analyses of the water collected from the leak chase channels and any criteria for evaluation or acceptance would be continued in the period of extended operation. In addition, the staff was unclear if any future video inspections of the leak chase channels would be conducted.
Discussion:
PG&E agreed to supplement the response to RAI 82.1.32-4 to clarify this portion of the RAI.
- 2. The staff was unclear if the leakage from Unit 2 spent fuel pool is contained within the leak chase system, and no leakage has ever been observed through the walls or floors of the spent fuel spent fuel pool.
Discussion:
The applicant confirmed that no leakage has ever been observed through the walls or floors of the spent fuel pool. 8ased on the discussion, this portion of the response is clear.
- 3. The staff is unclear why there is leakage from Unit 1 spent fuel pool during outages only, and increase in leakage from Unit 2 spent fuel pool during outages.
Discussion:
The staff will issue a follow-up RAI to address the increased spent fuel pool leakage during outages.
-3 RAI82.1.33-1 In its July 19, 2010, response to RAI 82.1.33-1, the applicant summarized the details of the intake structure refurbishment program. However, the staff had the following observations:
- 1. The staff was not clear on the applicant's future inspection plan and frequency after refurbishment of the intake structure.
Discussion:
The staff will issue a follow-up RAI for clarification on the inspection frequency to be used during the period of extended operation on water-control structures.
- 2. The staff was unclear if applicant had any engineering evaluation which documented the degradation of the intake structure and corrective actions and if the engineering evaluation been documented in a calculation or report.
Discussion:
PG&E agreed to make the applicable engineering evaluations available for the staff to audit.
RAI 82.1.33-2 In its July 19, 2010, response to RAI 82.1.33-2, the applicant described the history and repairs on the discharge structure. However, the staff noted that the applicant stated that DCPP procedures require inspection on a refueling cycle interval frequency. In addition, the applicant has stated that the discharge structure was partially inspected in 1991 and 1999. The staff is unclear if any inspections have been performed on interior surfaces of the discharge structure since 1999. The applicant's aging management program for water-control structures states that inspections are implemented in accordance with the guidance in RG 1.127. However, RG 1.127 requires an inspection frequency of five years.
Discussion:
The staff will issue a follow-up RAI in conjunction with follow-up RAI 82.1.33-1 for clarification on the inspection frequency to be used during the period of extended operation on water-control structures.
- 4 RAt 82.1.33-3 In its July 19, 2010, response to RAI B2.1.33-3, the applicant described the history and inspection techniques for the discharge circulating water conduits (DCWC). However, the staff made the following observations:
- 1. The staff noted that the response indicated that the DCWCs were last inspected in a May 2002 Unit 1 outage and a May 2001 Unit 2 outage. RG 1.127 requires water control structures to be inspected every five years. The staff is unclear of the current inspection frequency and the inspection frequency of the DCWC for the period of extended operation.
Discussion:
The staff will issue a follow-up RAI in conjunction with follow-up RAI B2.1.33-1 to clarify the inspection frequency on water-control structures.
- 2. The staff noted that the applicant stated that submerged structures, systems, and components that are continuously under water should be inspected every planned refueling outage; however, discretion on inspection frequency is left up to the system engineer so long as it does not exceed ten years. The staff is unclear how the ten year inspection frequency is justified.
Discussion:
The staff will issue a follow-up RAI in conjunction with follow-up RAI B2.1.33-1 to clarify the inspection frequency on water-control structures.
- 3. The staff was unclear from the response, which portions of the discharge structures are inaccessible for inspection due to marine growth. It is also unclear how frequently the marine growth is removed, and when it is removed, what portion of the inaccessible area is made accessible.
Discussion:
The staff will issue a follow-up RAI for clarification on the inspection technique and methodology for portions of the discharge conduit that are inaccessible due to marine growth.
September 15, 2010 LICENSEE: Pacific Gas and Electric Company FACILITY: Diablo Canyon Nuclear Power Plant, Units 1 and 2
SUBJECT:
SUMMARY
OF TELEPHONE CONFERENCE CALL HELD ON AUGUST 12, 2010, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND PACIFIC GAS AND ELECTRIC COMPANY CONCERNING RESPONSES TO REQUESTS FOR ADDITIONAL INFORMATION RELATED TO THE DIABLO CANYON NUCLEAR POWER PLANT, UNITS 1 AND 2, LICENSE RENEWAL APPLICA TION The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Pacific Gas and Electric Company (PG&E or the applicant) held a telephone conference call on August 12, 2010, to obtain clarification on the applicant's response to request for additional information (RAI) regarding the Diablo Canyon Nuclear Power Plant license renewal application.
By letter dated July 19, 2010, PG&E sent the staff a response to RAlletter dated June 21,2010, regarding structures aging management programs. The staff reviewed the information contained therein, and requested a telephone conference call. The telephone conference call was useful in clarifying the intent of PG&E's response. Enclosure 1 provides a listing of the participants. Enclosure 2 provides discussions on RAI responses for which the staff requested clarification. PG&E will submit supplemental responses, as necessary, within 30 days of the issuance of this summary. Follow-up RAls, determined to be necessary, will be issued separately by a formal letter.
The applicant had an opportunity to comment on this summary.
IRA!
Nathaniel Ferrer, Project Manager Projects Branch 2 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-275 and 50-323
Enclosures:
As stated cc w/encls: Distribution via Listserv DISTRIBUTION:
See next page ADAMS Accession No.: ML102390155 OFFICE LA:DLR PM:RPB2:DLR BC:RPB2:DLR PM:RPB2:DLR NAME IKing NFerrer DWrona NFerrer DATE 09/01/10 09/02/10 09/10/10 09/15/10 OFFICIAL RECORD COpy
Memorandum to Pacific Gas and Electric Company from N. Ferrer dated September 15,2010
SUBJECT:
SUMMARY
OF TELEPHONE CONFERENCE CALL HELD ON AUGUST 12, 2010, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND PACIFIC GAS AND ELECTRIC COMPANY CONCERNING RESPONSES TO REQUESTS FOR ADDITIONAL INFORMATION RELATED TO THE DIABLO CANYON NUCLEAR POWER PLANT, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION DISTRIBUTION:
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