L-PI-12-088, Supplement to License Amendment Request (LAR) to Add Diesel Fuel Oil License Bases and Revise Technical Specifications (TS) 3.7.8, Cooling Water (Cl) System and 3.8.3, Diesel Fuel Oil (TAC Nos. ME6849 and ME6850)

Supplement to License Amendment Request (LAR) to Add Diesel Fuel Oil License Bases and Revise Technical Specifications (TS) 3.7.8, Cooling Water (Cl) System and 3.8.3, Diesel Fuel Oil (TAC Nos. ME6849 and ME6850)

ML12279A116
Person / Time
Site:	Prairie Island
Issue date:	10/04/2012
From:	Sorensen J Northern States Power Co, Xcel Energy
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
L-PI-12-088, TAC ME6849, TAC ME6850
Download: ML12279A116 (7)

Text

Xcel Energym L-PI-12-088 10 CFR 50.90 U S Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant Units 1 and 2 Dockets 50-282 and 50-306 Renewed License Nos. DPR-42 and DPR-60 Supplement to License Amendment Request (LAR) to Add Diesel Fuel Oil License Bases and Revise Technical Specifications (TS) 3.7.8, "Cooling Water (CL) Svstem" and 3.8.3, "Diesel Fuel Oil" (TAC Nos. ME6849 AND ME68501 By letter dated August 11,2011 (Agencywide Documents Access and Management System (ADAMS) Accession No. MLI 12240140), Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter "NSPM"), requested NRC review and approval of additional diesel fuel oil (DFO) license bases and amendments to TS 3.7.8, "Cooling Water (CL) System" and 3.8.3, "Diesel Fuel Oil" for the Prairie Island Nuclear Generating Plant (PINGP), Units Iand 2. NSPM supplemented this LAR by letters dated February 21, 2012 (ML12054A057) and July 9, 2012 (ML12192A213). By email dated August 24,2012 (ML12261A393), NRC Staff provided clarification questions on information provided in the July 9, 2012 (ML12192A213) supplement. The enclosure to this letter provides responses to the NRC Staff clarification questions. NSPM submits this supplement in accordance with the provisions of 10 CFR 50.90.

The supplemental information provided in this letter and enclosure does not impact the conclusions of the Determination of No Significant Hazards Consideration or Environmental Assessment presented in the August 11, 201 1 (MLI 12240140) submittal as supplemented February 21,2012 (ML12054A057) and July 9,2012 (ML12192A213).

In accordance with 10 CFR 50.91, NSPM is notifying the State of Minnesota of this LAR supplement by transmitting a copy of this letter and enclosure to the designated State Official.

If there are any questions or if additional information is needed, please contact Mr. Dale Vincent, P.E., at 651-388-1121.

1717 Wakonade Drive East Welch, Minnesota 55089-9642 Telephone: 651.388.1 121

Document Control Desk Page 2 Summarv of Commitments This letter contains no new commitments and no revisions to existing commitments.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on OCT 0 4 2012 Joel P. ~ o r e n s e n Acting Site Vice President, Prairie Island Nuclear Generating Plant Northern States Power Company - Minnesota Enclosures (1) cc: Administrator, Region Ill, USNRC Project Manager, PINGP, USNRC Resident Inspector, PINGP, USNRC State of Minnesota

ENCLOSURE Response to Email Clarification Questions for License Amendment Request (LAR) to Add Diesel Fuel Oil License Bases and Revise Technical Specifications (TS) 3.7.8, "Cooling Water (CL) System" and 3.8.3, "Diesel Fuel Oil" (TAC Nos. ME6849 and ME6850)

This enclosure provides responses from Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter "NSPM"), to Nuclear Regulatory Commission (NRC) clarification questions provided by email dated August 24, 2012 (ML12261A393) regarding the LAR requesting NRC review and approval of additional diesel fuel oil (DFO) license bases and amendments to TS 3.7.8, "Cooling Water (CL)

System" and TS 3.8.3, "Diesel Fuel Oil" for the Prairie Island Nuclear Generating Plant (PINGP), Units 1 and 2, submitted by letters dated August 11, 201 1 (MLI 12240140) as supplemented February 21,2012 (ML12054A057) and July 9,2012 (ML12192A213).

NRC Clarification Question for NSPM Response to RAI EEEB-7 Technical Specification Surveillance Requirement (SR) 3.8.1.5 requires the licensee to verify, every 31 days, that the fuel oil transfer system operates to transfer fuel oil from storage tank to day tank.

In its letter dated February 21, 2012, NSPM stated in its response to RAI [Request for Additional Information] EEEB-Id, in part:

The Unit 1 fuel oil system has the capability to transfer fuel from any storage tank to any day tank as defined in the USAR [Updated Safety Analysis Report].

However, procedures are not in place to cover the many different scenarios for transferring fuel during a 14 day flooding event. The transfer paths will be dependent on the equipment operating and fuel oil levels in the various tanks.

The flow diagrams would be utilized to perform actions not covered under established procedures or [Abnormal Operating Procedures].

Describe how NSPM demonstrates compliance with SR 3.8.1.5 for operability of all of the flow paths credited in the design basis of the plant for 14-day operation during the design basis flood.

NSPM Response to EEEB-7 Clarification Question:

SR 3.8.1.5 states, "Verify the fuel oil transfer system operates to transfer fuel oil from storage tank to the day tank." Performance of SR 3.8.1.5 demonstrates the ability of each fuel oil transfer pump to operate and transfer fuel from its associated storage tank to its associated day tank. NSPM demonstrates compliance with SR 3.8.1.5 through monthly surveillances for Diesel Fuel Oil Testing which defines Unit specific steps within Page 1 of 5

Diesel Fuel Oil RAls the sampling procedures to operate each transfer pump and verify that a level change is seen at the associated day tank. This testing meets NSPM1sunderstanding of the requirements of this SR.

NRC Clarification Question for NSPM Response to RAI EEEB-8 Provide details for each EDG [Emergency Diesel Generator] fuel oil consumption (given licensing basis such as single failure) that will demonstrate capability of the fuel oil system to support 7-day EDG operation following any event evaluated in the PlNGP licensing documents. Details shall include the bounding Unit 1 and Unit 2 fuel oil consumption values (gallons) and a summary of the methodology, key assumptions, industry standards used, the basis for the parameters used, the EDG load profile that is considered bounding, and any relevant information that NSPM has used to derive the values (gallons) that will become a baseline 7-day fuel oil storage requirement.

NSPM Response to RAI EEEB-8 Clarification Question:

Unit 1 diesel fuel oil consumption volume:

Calculated Volume The Unit 1 diesel fuel oil system provides fuel oil to both the Unit 1 EDGs ( D l and D2) and the safeguards diesel driven cooling water pumps (DDCLPs). The calculated seven-day fuel oil consumption volume for the Unit 1 diesel fuel oil system is approximately 38,940 gallons for each train of which approximately 29,100 gallons is for the EDG.

A review of the design basis accidents considered in USAR Section 14 was performed to determine the expected longest duration for the major accident loads (for example, residual heat removal pumps, safety injection pumps, containment spray pumps). This review determined that the major loads should be considered for a maximum duration of eight hours, thereafter, the loads will be reduced.

To calculate the fuel oil consumed, ANSl N195-1976 is used. The time dependant load equation is used (including the 10% margin and periodic testing required by the standard). Although the ANSl standard applies to standby diesel generator equipment, to the extent practical, the standard was also applied to the diesel driven cooling water pumps (DDCLPs), since the Unit 1 diesel fuel oil system is shared between the EDGs and DDCLPs. Thus the DDCLP consumption included a fuel oil volume for periodic testing and 10% margin.

The EDG fuel oil consumption rate curve is based on factory and pre-operational testing data. The DDCLP consumption rate is based on the factory testing data.

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Diesel Fuel Oil RAls EDG Load Profile Considered Boundinq The bounding load profile considered is 2750 kW for the first eight hours and 1700 kW for timeframes greater than eight hours. This load profile bounds the expected loads and timeframes from the calculation which determines peak loading for the Unit 1 EDGs

( D l and D2) for the large break loss of coolant accident (LOCA). The initial eight hour timeframe bounds all design basis accident timeframes to secure the major accident loads. By using the combination of this loading and the eight hour timeframe, all design basis accident scenarios for peak loading and time to reduce the loading (that is, perform the transfer to recirculation) are bounded.

Key Assumptions The following assumptions are considered for fuel oil consumption:

- A minimum fuel oil density of 6.91 Iblgal is considered for the fuel oil consumption. This is based on guidance contained in ANSIIANS 59.51-1989, Appendix C, which specifies a minimum specific gravity of 0.83. This applies to both the EDGs and the DDCLPs.

- Any consumption rate used in the calculation is increased by 5%. This is based on review of the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> surveillance EDG runs. The fuel consumed during recent 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> runs was compared to the predicted consumption based on the manufacturer's and pre-operational testing consumption rates. This review noted a maximum difference of 3.9% less than actual, so a 5% factor has been used for conservatism.

- The first eight hours of EDG loading is assumed to be at the continuous rated load of 2750 kW for the Unit 1 (DllD2) EDGs, which bounds the peak expected loading for a large break LOCA of 2555.68 kW. After the initial eight hours, the loading is assumed to be 1700 kW based on bounding the expected long term loading (recirculation loading) for a large break LOCA of 1592.27 kW.

- The assumed consumption rate per kW for the first eight hours of loading is based on the factory and pre-operational testing consumption rate at approximately 2100 kW. The assumed consumption rate per kW after the initial eight hours is based on the consumption rate at factory and pre-operational testing consumption rate at approximately 1500 kW. Engine efficiency increases as engine power increases, thus the per kW consumption rate decreases as power increases.

- One performance of SR 3.8.1.3 (22500 kW for 260 minutes) at a load of 2500 kW for 90 minutes is assumed for the EDG periodic testing.

- One performance of the DDCLP surveillance procedure is assumed. Review of recent performances of this surveillance show that the test takes approximately one hour. To be conservative, a two hour timeframe is considered for this assumption.

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Diesel Fuel Oil RAls

- The use of Ultra-Low Sulphur Diesel (ULSD) fuel oil has been considered (NRC Information Notice (IN) 2006-22), but no increase in consumption is applied.

Based on testing done in response to IN 2006-22, the energy content of fuel oil received by PlNGP was similar to previous the fuel oil. Also, recent tests of the PINGP's fuel oil show the energy content is similar to previous fuel oil.

Unit 2 diesel fuel oil consumption volume:

Calculated Volume The calculated seven day fuel oil consumption volume for the Unit 2 EDGs is approximately 41,430 gallons for each train of fuel oil.

Methodology A review of the design basis accidents considered in USAR Section 14 was performed to determine the expected longest duration for the major accident loads (for example, residual heat removal pumps, safety injection pumps, containment spray pumps). This review determined that the major loads should be considered for a maximum duration of eight hours, thereafter, the loads will be reduced.

To calculate the fuel oil consumed, ANSI N195-1976 is used. The time dependant load equation is used (including the 10% margin and periodic testing required by the standard).

The EDG fuel oil consumption rate curve is based on factory testing data.

EDG Load Profile Considered Boundinq The bounding load profile considered is 3900 kW for the first eight hours and 2700 kW for timeframes greater than eight hours. This load profile bounds the expected loads and timeframes from the calculation which determines peak loading for the Unit 2 EDGs (D5 and D6) for the large break LOCA. The initial eight hour timeframe bounds all design basis accident timeframes to secure the major accident loads. By using the combination of this loading and the eight hour timeframe, all design basis accident scenarios for peak loading and time to reduce the loading (that is, perform the transfer to recirculation) are bounded.

Key Assumptions The following assumptions are considered for fuel oil consumption:

- The minimum fuel oil specific gravity considered is 0.83. The maximum fuel oil specific gravity considered is 0.89. This is based on the guidance contained in ANSIIANS 59.51-1989, Appendix C.

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Diesel Fuel Oil RAls

- The fuel oil consumption rate is assumed to be constant at 234 gramslkw-hr (prior to consideration of any increasing factors). This consumption rate corresponds to a load of 2400 kW. This bounds the minimum identified large break LOCA load of 2452.39 kW.

- The factory testing is assumed to have been done at the maximum specific gravity, but the site fuel oil is assumed to be at the minimum specific gravity.

This is applied as a consumption increase factor of approximately 7.23%

(0.8910.83).

- The first 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of EDG loading is assumed to be at a load of 3900 kW for the Unit 2 (D5lD6) EDGs, which bounds the peak expected loading for a large break LOCA of 3768.73 kW. After the initial eight hours, the loading is assumed to be 2700 kW based on bounding the expected long term loading (recirculation loading) for a large break LOCA of 2561.97 kW.

- One performance of SR 3.8.1.3 (25100 kW and 55300 kW for 260 minutes) at a load of 5400 kW for 90 minutes is assumed for the EDG periodic testing.

- The use of ULSD fuel oil has been considered (NRC IN 2006-22), but no increase in consumption is applied. Based on testing done in response to IN 2006-22, the energy content of fuel oil received by PlNGP was similar to previous the fuel oil. Also, recent tests of PINGP's fuel oil show the energy content is similar to previous fuel oil.

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