ML102360552

Summary of Telephone Conference Call Held on August 5, 2010, Between the U. S. Nuclear Regulatory Commission and Pacific Gas and Electronic Company Concerning Responses to Request for Additional Information Related to the Diablo Canyon Nucl

ML102360552
Person / Time
Site:	Diablo Canyon
Issue date:	09/22/2010
From:	Ferrer N License Renewal Projects Branch 2
To:	Pacific Gas & Electric Co
Ferrer, N B, NRR/DLR, 415-1045
References
Download: ML102360552 (8)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 22,2010 LICENSEE: Pacific Gas and Electric Company FACILITY: Diablo Canyon Nuclear Power Plant, Units 1 and 2

SUMMARY

OF TELEPHONE CONFERENCE CALL HELD ON AUGUST 5, 2010, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND PACIFIC GAS AND ELECTRIC COMPANY CONCERNING RESPONSES TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO THE DIABLO CANYON NUCLEAR POWER PLANT, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION 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 5, 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 (LRA).

By letter dated June 18, 2010, PG&E sent the staff a response to RAI letter dated May 24, 2010, regarding scoping and screening methodology. 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.

Nathaniel Ferrer, Safety 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 5, 2010 PARTICIPANTS AFFILIATIONS Nate Ferrer U.S. Nuclear Regulatory Commission (NRC)

Stan Gardocki NRC Garry Armstrong NRC Bill Rogers NRC Philippe Soenen Pacific Gas and Electric Company (PG&E)

Dan Gibbons PG&E Chalmer Myer Strategic Teaming And Resource Sharing (STARS)

Dave Kunsemiller STARS AI Saunders STARS Randall Boyd STARS Dan Shepard STARS Rye Davis STARS ENCLOSURE 1

Diablo Canyon Nuclear Power Plant, Units 1 and 2 License Renewal Application Request for Additional Information (Set 2)

Scoping and Screening RAI2.1-2 In its June 18,' 2010, response to request for additional information (RAI) 2,1-2, the applicant provided additional systems in scope for license renewal, which included the extraction steam and sanitary sewage systems, The staff made the following observations:

• The staff was unclear whether license renewal boundary drawings were created for the sanitary system to assist the staff in the review.

Discussion:

The staff will issue a follow-up RAI for clarification of the boundaries of the sanitary system.

• The applicant indicated in its response under revised license renewal application (LRA)

Table 2.3.3-18 that the heat exchanger for the isothermal chiller and chiller components are not in scope for license renewal due to its revised assessment of the secondary sampling system. However, on revised license renewal boundary drawings LR-DCPP 28-106728-03 and LR-DCPP-28-107728-03, the heat exchanger in the isothermal bath is still shown in scope for 10 CFR 54.4(a)(2).

Discussion:

PG&E indicated that the component in question is tubing, that is attributed to the piping components in LRA Table 2.3.3-18. Based on the discussion, this portion of the response is clear.

• On license renewal boundary LR-DCPP-15-106715-02, the applicant shows the service water loop at location 29-E through A in scope for license renewal. However, the heat exchanger in that loop was not identified in LRA Table 2.3.3-18.

Discussion:

The applicant confirmed that the loop in question is capped and abandoned in place.

The staff will issue a follow-up RAI to clarify the license renewal boundary.

• The applicant added the fire protection intended function for the compressed air system; however, the staff was unclear if previous functions missed would require additional components to be brought into scope.

ENCLOSURE 2

-2 Discussion:

The applicant clarified that the revision was concerning a containment isolation valve, which was already within the scope of license renewal. Based on the conversation, this portion of the response is clear.

RAI2.1-3 In its June 18, 2010, response to RAI 2.1-3, the applicant provided a revision to several LRA systems that were to reflect the additional design class 2 structure, systems, and component (SSCs) that were placed in scope for license renewal, as part of the Hosgri fault licensing basis.

However, the staff was unclear of how the evaluation was performed to include additional Hosgri-related SSCs within the scope of license renewal.

Discussion:

PG&E agreed to supplement the response to RAI 2.1-3.

RAI2.3-1 In its June 18, 2010, response to RAI 2.3-1, the applicant clarified the methodology in LRA Section 2.1.2.2 to indicate that the boundary between safety-related and nonsafety-related SSCs may be at the seismically supported safety-related component, if the failure of the connected nonsafety-related SSC would not adversely affect the safety-related SSC function.

However, the staff was unclear as to how the applicant addressed the structurally-attached nonsafety-related piping past the solenoid valves to the safety-related piping for seismic concerns.

Discussion:

PG&E agreed to supplement the response to RAI 2.3-1.

RAI2.3-2 In its June 18, 2010, response to RAI2.3-2, the applicant added the guard pipe of the supply piping to the volume control tank to the scope of license renewal. However, the staff noted that on license renewal boundary drawing, LR-DCPP-08-106708-05, the manual regulator, an open diaphragm valve and closed diaphragm valve were not depicted in scope for license renewal, whereas on license renewal boundary, LR-DCPP-08-1077708-05, the same components are captured in scope for 10 CFR 54.4(a)(2).

Discussion:

The staff will issue a follow-up RAI to clarify the discrepancy.

- 3 RAI2.3-3 In its June 18, 2010, response to RAI2.3-3, the applicant added the oity water and turbine sump system in scope for license renewal. However, the staff noted that indications in the license renewal boundary drawings and the Final Safety Analysis Report show there are fluid filled components (sumps, pumps, and piping) in the underground manholes for electrical systems, and fuel oil transfer pump vaults. If the components are in the same space as safety-related components they may need to be included in the scope of license renewal.

Discussion:

The staff will issue a follow-up RAI to clarify whether any additional components located in the underground manholes need to be added within the scope of license renewal.

RAI2.3-5 In its June 18, 2010 response to RAI 2.3-5, the applicant added the long-term cooling function to applicable components within the scope of license renewal. However, the staff made the following observations.

• Portions of the long term cooling function were highlighted in green for 10 CFR 54.4(a)(1) or (a)(3) instead of (a)(2) as stated in the LRA system description of intended function.

Discussion:

PG&E indicated that components of concern are highlighted green and within the scope of license renewal under 10 CFR 54.4(a)(3) to ensure that the intended function of "pressure boundary" is captured. Based on the discussions this portion of the response is clear.

• The applicant noted that the intended function of the flow path, which has now changed from leakage boundary to maintaining a flow path, could cause components such as strainers to have an intended function of "filter." The staff was unclear as to whether any additional components should be included within the scope of license renewal, based on the change of intended function.

Discussion:

The staff will issue a follow-up RAI to clarify whether any intended functions of components would change, requiring additional aging management review (AMR) for these components, due to the change in intended function for the long term cooling path.

-4 RAI2.3-6 In its June 18, 2010 response to RAI 2.3-6, the applicant stated that thermowells are represented in the AMR tables as piping, piping components, and piping elements. However, in reviewing the LRA Table 3.4.2-3 for the feedwater system, the staff found that the applicant did not provide a line item for stainless steel piping for treated water environments, which typically includes thermowells.

Discussion:

The applicant confirmed that the thermowells in the feedwater system are made of the same material as the piping they are attached, and are in scope for license renewal under the "piping elements" component type. Based on the discussion, this response is clear.

RAI2.3.3.14-1 In its June 18, 2010, response to RAI2.3.3.14-1, the applicant stated that the pressure boundary intended function for the unloader line was removed from license renewal. However, the staff noted that the unloader line, the compressor, and possibly the air dryers have a function of pressure boundary to maintain the safety related function of the air receivers.

Discussion:

PG&E agreed to supplement the response to RAI 2.3.3.14-1.

RAI 2.3.3.14-2 In its June 18,2010 response to RAI 2.3.3.14-2, the applicant stated other base-mounted components have been reviewed, and no other changes to the LRA are required. However, the staff was unclear if this methodology was followed in the following license renewal boundary drawing locations:

• On license renewal boundary drawings LR-DCPP-11-106711-02 and LR-DCPP-11 107711-02 at location 26-C, the F.4.a flag is depicted in between the hood assembly area.

• 'On license renewal boundary drawing LR-DCPP-14-107714-09 at location 93-8, the F.4.a flag is depicted on piping near a valve before it enters continuation arrow.

• On license renewal boundary drawings LR-DCPP-23A-106723-03 and LR-DCPP-23A 107723-03 at location 36- C through A, the F.4.a flags are depicted on piping leading into PNL-209 and PNL-210.

Discussion:

PG&E agreed to supplement the response to RAI 2.3.3.14-2.

• .. ML102360557 OFFICE LA:DLR PM:RPB2:DLR BC:RPB2:DLR PM:RPB2:DLR NAME IKing NFerrer DWrona NFerrer wlcomments DATE 9/8/10 9/10/10 9/16/10 9/22/10 Memorandum to Pacific Gas and Electric Company from N. Ferrer dated September 22.2010

SUMMARY

OF TELEPHONE CONFERENCE CALL HELD ON AUGUST 5, 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:

HARDCOPY:

DLRRF E-MAIL:

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