ML13099A043

Request for Additional Information Following 4/3/13 Calculation Audit, Technical Specification Changes to Support Installation of GE Hitachi Power Range Neutron Monitoring System; Implementation of Arts/Mellla

ML13099A043
Person / Time
Site:	Columbia
Issue date:	04/10/2013
From:	Lyon C Plant Licensing Branch IV
To:	Reddeman M Energy Northwest
Lyon C
References
TAC ME7905
Download: ML13099A043 (4)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 April 10, 2013 Mr. Mark E. Reddemann Chief Executive Officer Energy Northwest P.O. Box 968 (Mail Drop 1023)

Richland, WA 99352-0968

SUBJECT:

COLUMBIA GENERATING STATION - REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO IMPLEMENT PRNM/ARTS/MELLLA (TAC NO. ME7905)

Dear Mr. Reddemann:

On April 3, 2013, an audit was conducted by G. Singh and R. Alvarado of the U.S. Nuclear Regulatory Commission (NRC) staff of certain calculations used by Energy Northwest (EN, the licensee) in its license amendment request for Columbia Generating Station that would allow the licensee to expand the operating domain by the implementation of Average Power Range Monitor/Rod Block MonitorlTechnical Specifications/Power Range Neutron Monitoring/Maximum Extended Load Line Limit Analysis (ARTS/PRNM/MELLLA). The calculation audit was conducted at the NRC headquarters in Rockville, Maryland. The audit was supported by G. Carlisle and A. Poulos of GE Hitachi Nuclear Energy (GEH), the contractor for the licensee.

Following the audit, an exit telephone call was held with M. Huiatt (EN), S. Rudy, et al. (GEH),

and F. Lyon, et al. (NRC).

Based on the NRC staff's audit, the staff determined that additional information identified in the enclosure to this letter is needed in order for the NRC staff to complete its review. The draft copy of the request for additional information (RAI) was provided to Ms. Lisa Williams of your staff via e-mail on April 8, 2013. Please provide your response to the RAI within 30 days of the date of this letter. If you have any questions regarding this matter, I may be reached at (301) 415-2296 or via e-mail at Fred.Lyon@nrc.gov.

Sincerely,

~

Carl F. Lyon, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-397

Enclosure:

As stated cc w/encl: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST TO IMPLEMENT PRNM/ARTS/MELLLA ENERGY NORTHWEST COLUMBIA GENERATING STATION DOCKET NO. 50-397 On April 3, 2013, an audit was conducted by G. Singh and R. Alvarado of the U.S. Nuclear Regulatory Commission (NRC) staff of certain calculations used by Energy Northwest (EN, the licensee) in its license amendment request for Columbia Generating Station (CGS) that would allow the licensee to expand the operating domain by the implementation of Average Power Range Monitor/Rod Block MonitorfTechnical Specifications/Power Range Neutron Monitoring/Maximum Extended Load Line Limit Analysis (ARTS/PRNM/MELLLA). The calculation audit was conducted at the NRC headquarters in Rockville, Maryland. The audit was supported by G. Carlisle and A. Poulos of GE Hitachi Nuclear Energy (GEH), the contractor for the licensee. Following the audit, an exit telephone call was held with M. Huiatt (EN),

S. Rudy, et al. (GEH), and F. Lyon, et al. (NRC).

The following requests for additional information (RAls) were discussed by the NRC staff with EN staff and its contractor GEH staff during the calculation audit exit meeting on April 3, 2013:

1. Please explain whether EN is planning to use filtered or unfiltered set points for establishing the low/intermediate or high power trip set point (

Reference:

Attachment A to NEDC-33507P, "APRM/RBMfTechnical Specifications /

Maximum Extended Load Line Limit Analysis (ARTS/MELLLA)"). Please document how the use of filtered or unfiltered values will be determined and explicitly state how these limits will be conservatively applied for implementation of PRNM/ARTS/MELLLA at CGS.

2. The following clarification was provided to RAI 17 (RAI regarding use of 3-Sigma errors), dated March 12, 2013: Not all of the 3-Sigma errors were explained in the information provided by the licensee; specifically, please explain the use of 3-Sigma for the rod block monitor tracking Process Measurement Accuracy (PMA) trip set points.

3. What are the bases for the Oscillation Power Range Monitor set points? This question was subsequently resolved by information located in NEDC-33685P, "Digitall&C-ISG-06 Compliance for Columbia Generating Station, NUMAC Power Range Neutron Monitoring Retrofit Plus Option /1/ Stability Trip Function. "

Enclosure

-2

4. Please clarify how as-found tolerance and as-left tolerance values are defined by EN for CGS. Define the error terms used in determining their values. TSTF-493 Technical Specifications Task Force (TSTF) Change Traveler TSTF-493, "Clarify Application of Setpoint Methodology for LSSS [Limiting Safety System Setting]

Functions," provides guidance, but does not specify the error terms, for calculating these numbers.

5. Please explain how the 95/95 probability/confidence criteria are being implemented in the GEH set point methodology for the set points under review.

ML13099A043 *email dated OFFICE NRRfDORLlLPL4/PM NRRfDORLlLPL4/LA NRR/DElEICB/BC NRRfDORULPL4/BC NRRfDORLlLPL4/PM NAME FLyon JBurkhardt JThorp' MMarkley FLyon DATE 4/9/13 4/9/13 4/5/13 4/9/13 4/10/13