CP-201300787, Multi-Unit/Multiple Release Point Dose Assessment Capability
| ML18200A178 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 07/01/2013 |
| From: | Flores R, Madden F Luminant Power |
| To: | Wiggins J Office of Nuclear Security and Incident Response |
| References | |
| CP-201300787, TXX-13102 | |
| Download: ML18200A178 (3) | |
Text
Rafael Flores Senior Vice President
& Chief Nuclear Officer rafael.Rores@Luminant.com Lurninant Power P 0 Box 1002 6322 North FM 56 Glen Rose, TX 76043 REF:
July 1,2013 Mr. James T. Wiggins Director, Nuclear Security and Incident Response U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
COMANCHE PEAK NUCLEAR POWER PLANT, DOCKET NOS. 50-445 AND 50-446, MULTI-UNIT/MULTIPLE RELEASE POINT DOSE ASSESSMENT CAPABILITY
REFERENCE:
NEI Letter, Commitment for Implementation of Multi-Unit Dose Assessment Capability; Pollock to Wiggins; dated March 14,2013
Dear Mr. Wiggins:
In accordance with the referenced letter, Lurninant hereby provides the following information concerning the capability to perform offsite dose assessment during an event involving multiple release sources (e.g.,
assess concurrent releases from a reactor containment and a spent fuel pool) at Comanche Peak Nuclear Power Plant Units 1 and 2 (CPNPP).
A summaw of the current capability to ~erform multi-unit/multi-source dose assessment CPNPP uses the CPAMPEDE (Comanche Peak Assessment Model Projecting Estimated Dose Evaluation) computer program described below to perform dose assessment calculations under emergency conditions. CPAMPEDE is a Windows-based, menu driven program which has the capability to provide near real time estimates of potential doses to individuals from releases of radioactive materials via the atmospheric pathway and to back-calculate release rates from field measurements.
CPAMPEDE uses a straight-line Gaussian plume model for initial dose projections within the Plume Exposure Pathway EPZ. It uses a segmented-plume model for tracking wind shifts and plume deposition over portions of the Ingestion Exposure Pathway EPZ. CPAMPEDE can use system parameters and radiation monitor readings from plant monitoring systems, or the results of in-plant sampling, to estimate th; source term and release rate. It then uses these values with meteorological data, which are input manually, to estimate plume location and to calculate projected doses. CPAMPEDE can also use default data in the absence of plant-specific data. Plume transport and diffusion are based on meteorological data measured on the site meteorological tower.
CPAMPEDE currently models a release from a single pathway for one unit. Release pathways include monitored unit vent release, monitored containment release, monitored steam generator tube rupture release, and an monitored steam generator tube rupture release. Source terms for five pre-defined source terms are used to manually input data taken from plant monitors. The five source term options are: noble gas; noble gas and iodine; coolant inventory; fuel gas gap inventory; and core melt inventory.
A member of the STARS Alliance Callaway. Comanche Peak. Diablo Canyon. Palo Verde. San Onofre. South Texas Project. Wolf Creek
U. S. Nuclear Regulatory Commission TXX-13102 Page 2 07/01 1201 3 CPAMPEDE also provides an option to manually enter a radionuclide mix inventory.
In order to perform multi-unit and/or multiple release pathway dose assessment, CPNPP would perform individual computations for each unit and/or each release path. The results of these runs would be manually, or in a spreadsheet, added together to provide a dose estimate from all release sources.
Schedule to establish multi-unit/multi-source dose assessment capabilitv
- 1.
Luminant will fully proceduralize and implement interim measures for multi-unit/multi-source dose assessment capabilities by November 30,2013.
- 2.
Permanent capabilities will be implemented no later than December 31, 2014.
Estimated action completion dates associate with each kev scheduled action or milestone A description of how the implementation will be tracked and the associated tracking identifiers 1
3 4
7 Luminant is using the site Corrective Action Program to track implementation actions of this project.
Accordingly, a Condition Report has been issued to ensure the milestones and actions discussed above are implemented under the schedule provided (CR-2013-005802).
This letter does not contain any regulatory commitments.
Action/Milestone Identify interim compensatory measures for multi-unit/multi-source dose assess capabilities Develop and conduct training for implementing interim compensatory measures Upgrade CPAMPEDE software for multi-unit/multi-source dose assessment capability Implement upgraded CPAMPEDE including post-training improvements/modifications to CPAMPEDE and required procedure changes, training, if necessary Should you have any questions concerning the content of ths letter, please contact Robert Kidwell at (254) 897-5310.
Estimated Completion Date July 31,2013 November 30,2013 July 31,2014 December 31,2014
U. S. Nuclear Regulatory Commission TXX-13102 Page 3 07/01 /201 3 Sincerely, Lurninant Generation Company LLC Rafael Flores By:
Fred W. Madden I
Director, Oversight & Regulatory Affairs c -
A. T. Howell, Region IV B. K. Singal, NRR Resident Inspectors, Comanche Peak