ML113330116

Email, 11/1/2011 Pre-Licensing Conference Call to Discuss the Topic of Expected Impact of Chemical Effects on GSI-191 Risk-Informed Evaluation, Phenomena Identification and Ranking Table Items (TAC ME5358-ME5359)

ML113330116
Person / Time
Site:	South Texas
Issue date:	11/29/2011
From:	Balwant Singal Plant Licensing Branch IV
To:	Paul J South Texas
Singal, Balwant, 415-3016, NRR/DORL/LPL4
References
TAC ME5358, TAC ME5359, GSI-191
Download: ML113330116 (1)

Text

From: Singal, Balwant Sent: Tuesday, November 29, 2011 8:13 AM To: Paul, Jamie Cc: Grantom, Carl; Klein, Paul; Bailey, Stewart

Subject:

Conference Call Pre-Licensing Public Meeting - November 1, 2011 A conference call pre-licensing public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) staff and STP Nuclear Operating Company (STPNOC) on November 1, 2011 to discuss the topic of Expected Impact of Chemical Effects on GSI-191 Risk-Informed Evaluation for South Texas Project and STPNOCs proposed approach. The NRC staff agreed to provide a list of the expert panel chemical effects phenomena identification and ranking table (PIRT) items that should be re-visited by STPNOC. The previous NRC staff disposition (Agencywide Documents Access and Management System (ADAMS) Accession No. ML102280594) for some of these items relied on the conservative assumptions in licensee chemical effect evaluations. The NRC staff believes that STPNOC should re-visit the following PIRT items:

Item # Phenomenon 1.1, 1.2, 1.5 Reactor Coolant System (RCS) Coolant Chemistry/ pH Variability/

Emergency Core Cooling System (ECCS) injection of Boron 1.4 Containment Spray CO2 Scavenging 2.1 Radiological Conditions 2.5 Debris Bed Chemical Reactions 3.1 Crud Release 3.2 Jet Impingement 3.3 Debris Bed particulate to fiber ratio 3.5 Containment Spray Transport 3.6 Initial Debris Dissolution 3.7 Lead Shielding 3.8 Copper Source Term 3.11 Advanced Metallic Corrosion 3.12 Biological Growth in Debris Beds 3.13, 7.3 Fuel Deposition/Spalling 4.2 Heat Exchanger Solid Species Formation 4.3 Reactor Core Precipitation 4.5 Co-precipitation 5.1 Inorganic Agglomeration 6.2 Organic Agglomeration 6.4 Coating Dissolution (unqualified) 7.4 Reactor Core Diminished Heat Transfer 7.5 Blocking of Flow Passages 7.6 Reactor Core Particulate Settling Further clarifications can be provided during the upcoming conference call pre-licensing public meeting scheduled for December 1, 2011.

Thanks.

Balwant K. Singal Senior Project Manager (Comanche Peak, STP, and Palo Verde)

Nuclear Regulatory Commission Division of Operating Reactor Licensing Balwant.Singal@nrc.gov Tel: (301) 415-3016 Fax: (301) 415-1222