ML080790545

Request for Additional Information, License Amendment Request 07-004, Changes to Technical Specifications to Revise Rated Thermal Power from 3458 Mwt to 3612 Mwt (De/Eeeb Follow-up RAI)

ML080790545
Person / Time
Site:	Comanche Peak
Issue date:	03/31/2008
From:	Balwant Singal NRC/NRR/ADRO/DORL/LPLIV
To:	Blevins M Luminant Generation Co
Singal, Balwant, 415-3016, NRR/DORL/LPL4
References
TAC MD6615, TAC MD6616
Download: ML080790545 (6)

Text

March 31, 2008 Mr. M. R. Blevins Executive Vice President

& Chief Nuclear Officer Luminant Generation Company LLC ATTN: Regulatory Affairs P. O. Box 1002 Glen Rose, TX 76043

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION, LICENSE AMENDMENT REQUEST 07-004, CHANGES TO TECHNICAL SPECIFICATIONS TO REVISE RATED THERMAL POWER FROM 3458 MWT TO 3612 MWT (TAC NOS. MD6615 AND MD6616)

Dear Mr. Blevins:

By letter to the U.S. Nuclear Regulatory Commission (NRC) dated August 28, 2007, as supplemented by letters dated October 24, 2007, and January 10 and 31, February 21 and 28, and March 6 and 13, 2008, TXU Generation Company LP (subsequently renamed Luminant Generation Company LLC) submitted Technical Specification changes to revise the rated thermal power for Comanche Peak Steam Electric Station, Units 1 and 2, from 3458 megawatts thermal (MWt) to 3612 MWt for NRC review in accordance with Section 50.90 of Title 10 of the Code of Federal Regulations.

The NRC staff has determined that additional information is required to complete the review of the application. The specific information requested is addressed in the enclosure to this letter.

The enclosed request for additional information (RAI) was also sent to Mr. Jimmy Seawright via e-mail on March 19 and March 24, 2008. As agreed, please provide your response to the enclosed RAI by April 18, 2008.

The NRC staff considers that timely responses to RAIs help ensure sufficient time is available for NRC staff to complete its review and contribute toward the NRCs goal of efficient and effective use of staff resources.

If you have any questions, please contact me at (301) 415-3016.

Sincerely,

/RA/

Balwant K. Singal, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-445 and 50-446

Enclosure:

Request for Additional Information cc w/encl: See next page

ML080790545 NRR-088 (*) RAI input via e-mail dated OFFICE DORL/LPL4/PM DORL/LPL4/LA DE/EEEB/BC DSS/SRXB/BC DORL/LPL4/BC NAME BSingal:sp JBurkhardt GWilson (*) GCranston (*) THiltz DATE 3/31/08 3/31/08 3/19/08 3/21/08 3/31/08 Comanche Peak Steam Electric Station (10/2007) cc:

Senior Resident Inspector Mr. Richard A. Ratliff, Chief U.S. Nuclear Regulatory Commission Bureau of Radiation Control P.O. Box 2159 Texas Department of Health Glen Rose, TX 76403-2159 1100 West 49th Street Austin, TX 78756-3189 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Mr. Brian Almon 611 Ryan Plaza Drive, Suite 400 Public Utility Commission Arlington, TX 76011 William B. Travis Building P.O. Box 13326 Mr. Fred W. Madden, Director 1701 North Congress Avenue Regulatory Affairs Austin, TX 78701-3326 Luminant Generation Company LLC P.O. Box 1002 Ms. Susan M. Jablonski Glen Rose, TX 76043 Office of Permitting, Remediation and Registration Timothy P. Matthews, Esq. Texas Commission on Environmental Morgan Lewis Quality 1111 Pennsylvania Avenue, NW MC-122 Washington, DC 20004 P.O. Box 13087 Austin, TX 78711-3087 County Judge P.O. Box 851 Anthony P. Jones Glen Rose, TX 76043 Chief Boiler Inspector Texas Department of Licensing Environmental and Natural and Regulation Resources Policy Director Boiler Division Office of the Governor E.O. Thompson State Office Building P.O. Box 12428 P.O. Box 12157 Austin, TX 78711-3189 Austin, TX 78711

REQUEST FOR ADDITIONAL INFORMATION RELATED TO REVIEW ASSOCIATED WITH STRETCH POWER UPRATE LUMINANT GENERATION COMPANY LLC COMANCHE PEAK STEAM ELECTRIC STATION, UNITS 1 AND 2 DOCKET NOS. 50-445 AND 50-446 By letter to the U.S. Nuclear Regulatory Commission (NRC) dated August 28, 2007, as supplemented by letters dated October 24, 2007, and January 10 and 31, February 21 and 28, and March 6, and 13, 2008, TXU Generation Company LP (subsequently renamed Luminant Generation Company LLC, the licensee) submitted Technical Specification (TS) changes to revise the rated thermal power for Comanche Peak Steam Electric Station (CPSES), Units 1 and 2, from 3458 megawatts thermal (MWt) to 3612 MWt for NRC review.

The NRC staff has determined that the additional information, as requested by the Electrical Engineering and Reactor Systems Branches (follow-up request), is required to complete the review of the application. It should be noted that there may be further requests for additional information (RAI) while NRC staff develops the safety evaluation.

This RAI was also sent to Mr. Jimmy Seawright via e-mail on March 19, and 24, 2008.

ELECTRICAL ENGINEERING BRANCH

1. In its RAI response dated February 21, 2008, the licensee stated (in response to NRC Question 1), "[i]t is, and was our intent, to modify the temperature profiles utilized by the equipment qualification program to bound or reflect any changes that are the result of the SPU LOCA [stretch power uprate loss-of-coolant accident] curve. A bounding temperature profile will be incorporated into design drawings and used as an input for EQ

[environmental qualification] packages. The PAOT [post-accident operability time]

margin will be recalculated using this revised profile." The licensee's RAI response dated January 10, 2008, provided an SPU LOCA curve and EQ profile curve (Figure E1-1). The two curves appear to continue to overlap or crossover beyond the 24-hour point and diverge after approximately 1.00E+06 seconds. It is not clear which curve is used for supporting adequacy of the EQ life of equipment.

Provide the following information:

(a) Clarify the overlap points of the SPU LOCA curve and EQ profile curve to support bounding conditions.

(b) Identify the process to be used to modify the temperature profiles utilized by the EQ program to bound (establish necessary margin) any changes that are the result of the SPU LOCA curve.

(c) Identify the mission time of EQ components beyond 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

2. In the letter dated January 10, 2008, the licensee stated (in response to NRC Question 3), "[a]s described in LAR [license amendment request] section 2.3.1.2.2, for the Unit 1 HELB [high-energy line break] small temperature increase, a component specific evaluation determined the equipment is qualified. However, the Unit 2 HELB temperature evaluation is ongoing and is expected to be completed by April 15, 2008."

Provide the requisite analysis/evaluation to enable the NRC staff to complete its safety evaluation.

3. In its RAI response dated February 21, 2008, the licensee stated (in response to NRC Question 3), "[t]he changes that will be introduced by the replacement of the main transformers are small from the grid perspective."

The NRC staff considers that the changes in main transformer size and impedance can significantly impact the available short circuit current in the plant auxiliary system when the unit is on line and the auxiliaries are powered from the unit auxiliary transformers.

Confirm that studies have been completed to verify that available short circuit currents, for the minimum specified main transformer impedance, are within the rating of the plant auxiliary switchgear.

4. In the Stretch Power Uprate Licensing Report (SPULR), Enclosure 1 (WCAP 16840-P),

Section 2.2.2.6.2, the following analysis is provided for the Reactor Coolant Pump (RCP) motors, "[f]or hot loop conditions, a stator winding temperature rise of 68.2 EC [degrees Celsius] is compared to class B insulation. For cold loop conditions a stator winding temperature rise of 106 EC is compared to class F insulation requirements."

Provide the following information:

(a) Confirm the insulation class of RCP motors and verify the adequacy of the insulation to withstand higher operating temperatures.

(b) Confirm the requisite evaluations have been completed to verify the adequacy of cables and containment penetrations associated with the RCP motors operating at higher currents.

5. In the SPULR, Enclosure 1 (WCAP 16840-P), Section 2.2.4.2.2, it is stated that, for the Auxiliary Feedwater System, the feedline break analysis requires a minimum flow of 430 gallons per minute (gpm) compared to the current requirement of 400 gpm. This is approximately a 7.5 percent increase and considered within the rating of the pump and motor. The CPSES, Units 1 and 2 FSAR Table 8.3-1 provides a nameplate rating of 700 horsepower for the Auxiliary Feedwater Pump and indicates that kilowatt loading on the Emergency Diesel Generator (EDG) is based on actual demand.

Provide the following information:

(a) Confirm that the EDG loading calculations, fuel oil consumption and associated test procedures, if applicable, have been revised to accommodate the increase in EDG loading.

(b) Generically, for most pumps and motors, it is stated in the SPULR that there are no changes in pump flow rates even though the SPU will result in requiring higher decay heat-removal capability during all postulated conditions. This implies that the pumps will be running for a longer duration to remove decay heat. Confirm that EDG fuel oil consumption calculation, if load dependant, has been revised for extended pump operation.

6. In the SPULR, Enclosure 1 (WCAP 16840-P), Section 2.3.5.2.1, related to Loss of Ventilation during Station Blackout (SBO), it is stated that the turbine-driven auxiliary feedwater pump area temperature is expected to reach 131.1 degrees Fahrenheit (EF) during an SBO event.

Confirm whether or not the feedwater pump has any electrical components local to the pump. If yes, confirm the components are qualified for the expected environment.

REACTOR SYSTEMS BRANCH

1. Explain why the peak Reactor Coolant System (RCS) pressure in the turbine trip analysis SPULR, Table 2.8.5.2.1.2.4-1), in which the first trip is credited, is greater than the peak RCS pressure in the turbine trip overpressure analysis (TXX-08014, dated February 28, 2008), in which the first trip is not credited.

2. Explain why the high pressurizer pressure trip signal in the turbine trip analysis (SPULR Table 2.8.5.2.1.2.4-1), is generated later than the high pressurizer pressure trip signal in the turbine trip overpressure analysis (TXX-08014, dated February 28, 2008).

3. Describe the analyses, and provide the results, that support the high nuclear flux setpoints for operation with inoperable Main Steam Safety Valves (Table 2.8.4.2-3 of TXX-08014, dated February 28, 2008).

4. Explain the large difference between the proposed SPU setpoints and the current setpoints (Table 2.8.4.2-3 of TXX-08014, dated February 28, 2008).