ML13183A060

Offsite Assessment Capability During an Event Involving Multiple Release Sources

ML13183A060
Person / Time
Site:	Millstone
Issue date:	06/26/2013
From:	Heacock D Dominion, Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML13183A060 (5)

Text

Dominion Nuclear Connecticut, Inc.

5Y)00 Dominion Boulevard, Glen Allen, VA 23060 Dominion Web Address: www.dom.com June 26, 2013 U.S. Nuclear Regulatory Commission Serial No. 13-242B Attention: Document Control Desk NLOS/VDC R2 Washington, DC 20555 Docket Nos. 50-336 50-423 License Nos. DPR-65 NPF-49 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNITS 2 AND 3 OFFSITE DOSE ASSESSMENT CAPABILITY DURING AN EVENT INVOLVING MULTIPLE RELEASE SOURCES In a letter to the Nuclear Energy Institute (NEI) from the NRC dated February 27, 2013 (ML13029A632), the NRC requested additional detailed information regarding licensee's site-specific, current or planned, multi-unit dose assessment capabilities. In response to the Director, Nuclear Security and Incident Response, dated March 14, 2013 (ML13073A522), NEI notified the NRC that licensees would provide letters directly to the NRC describing multi-unit/multi-source dose assessment capability.

In accordance with the NEI letter, Dominion Nuclear Connecticut, Inc. (DNC) provides the following information regarding the capability to perform offsite dose assessment at Millstone Power Station (MPS) during an event involving multiple release sources (e.g.,

the ability to assess concurrent releases from reactor containment and the spent fuel pool).

Currently, MPS uses Meteorological Information Dose Assessment System (MIDAS) software from ABS Consulting, Inc., as its dose calculation model. MIDAS is a personal computer based program for rapidly assessing the radiological impact of accidents at nuclear power plants. It calculates total effective dose equivalent (TEDE) and thyroid doses. Source term information is derived from plant effluent monitors, reactor coolant system (RCS) or containment samples, field monitoring teams, or a default design basis accident scenario. In the event of a set of events involving multiple units/sources, individual dose assessment results can be summed to determine a total offsite dose assessment result.

Furthermore, an upgraded version of MIDAS software with a Multiple Accident Report Combiner (MARC) MIDAS Module has been procured. This MARC MIDAS Module can process up to five individual accidents and present results on a graphically displayed map with results combined for multiple release sources. The software upgrade will be implemented as indicated in the attached schedule.

Serial No. 13-242B Docket Nos. 50-336/423 Page 2 of 3 If you have any questions regarding this information, please contact Wanda Craft at (804) 273-4687.

Sincerely, David A. Heacock President and Chief Nuclear Officer Virginia Electric and Power Company Commitments made in this letter: None

Attachment:

Implementation Schedule for MARC MIDAS Module for Multi-Unit Dose Assessment Capability COMMONWEALTH OF VIRGINIA

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COUNTY OF HENRICO )

The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by David A. Heacock, who is President and Chief Nuclear Officer of Dominion Nuclear Connecticut, Inc. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that company, and that the statements in the document are true to the best /7-/of his know dge and belief.

Acknowledged before me this, day of 2013.

My Commission Expires: 3 I VICKI L.HULL Notary Public Notary Public I Commonwealth of Virginia 140542 Uu*n~mZ..liA ;vnirn@ Urn, .1 *fl1A P! misel m Ownllliril MiV %1 2014VI I

Serial No. 13-242B Docket Nos. 50-336/423 Page 3 of 3 cc: Director, Office of Nuclear Reactor Regulation One White Flint North Mail Stop 13H16 11555 Rockville Pike Rockville, Maryland 20852-2738 U.S. Nuclear Regulatory Commission Region I 2100 Renaissance Blvd.

Suite 100 King of Prussia, PA 19406-2713 Nadiyah S. Morgan Project Manager - Millstone Power Station U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 08 C2 Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station

Serial No. 13-242B Docket Nos. 50-336/423 ATTACHMENT IMPLEMENTATION SCHEDULE FOR MARC MIDAS MODULE FOR MULTI-UNIT DOSE ASSESSMENT CAPABILITY MILLSTONE POWER STATION UNITS 2 AND 3 DOMINION NUCLEAR CONNECTICUT, INC.

Serial No. 13-242B Docket Nos. 50-336/423 Attachment, Page 1 of 1 IMPLEMENTATION SCHEDULE The following table lists the milestones to implement the MARC MIDAS Module for multi-unit dose assessment capability at Millstone Power Station. The milestones are being tracked in the Central Reporting System via LCO01 164.

Item Implementation Estimated No. Task Completion Date Obtain MIDAS software with a Multiple Accident Complete Report Combiner (MARC) MIDAS Module 2 Complete acceptance testing of MARC MIDAS 09/03/2013 Module 3 Develop end-user documents (e.g., implementing 10/31/2013 procedures, guidelines, etc.)

4 Develop and conduct training on MARC MIDAS 09/09/2014 Module 5 Implement multi-unit dose assessment capability 12/31/2014