ML061790233

03/08/2006 - RIC 2006 Presentation - W3D - Maurice E. Dingler - GSI 191

ML061790233
Person / Time
Site:	Wolf Creek
Issue date:	03/08/2006
From:	Dingler M Wolf Creek
To:	Office of Nuclear Reactor Regulation
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Download: ML061790233 (9)

Text

RIC 2006 Session W3D GSI 191 ndustry Actions for GSI 191 Maurice (Mo) Dingler Technical Staff Engineer Wolf Creek Nuclear Operating Company 3/8/06

Key Message z GSI 191 is a priority issue for the industry z Licensees are implementing hardware changes at the earliest possible outage z The many facets of GSI 191 resolution are stretching the capabilities of the industry to resolve all facets by end of 2007

- Chemical effects issue is evolving as tests are being completed by the industry

- Downstream effects of debris on fuel is not a well understood phenomena

- Manufacturing, scheduling ,strainer testing

Industry Produced Documents major ones z NEI 02-01 Condition Assessment Guidelines Debris Source Inside PWR Containments z NEI 04-07 Pressurized Water Reactor Sump Performance Evaluation Methodology z WCAP 16362 -NP PRA Modeling for Sump Blockage z WCAP 16406-P Evaluation of Downstream Sump Debris Efforts in Support of GSI 191 z WCAP 16204 Evaluation of Potential WRG&EPG Changes to address NRC Bulletin 2003-01 Recommendations z Letter 2005-429 Transmittal of two WOG Documents - Template to Support WOG chemistry Efforts Follow on Testing and Framework to Interim Safety Assessment for GSI 191 z WCAP 16530 Evaluation of Post- Accident Chemical Effects in Containment Sump Fluids to Support GSI 191 z EPRI 101805 Design Basis Accident Testing of PWR Unqualified Original Equipment Manufacturer Coatings

After Initial Evaluations z Plants reviewing evaluations for refinements to the initial evaluation z Downstream Wear/ Blockage

- Pumps/Valves/Fuel concerns z Possible solutions

- Change out valves and pump wear surfaces

- Change the debris source term z Change insulation z Install debris interceptor z Have vendor test to determine screen specific bypass factor z Determine hardness factors of the certain debris z Combination of all

After Initial Evaluations z Chemical Effects

- Data provided to hardware vendors to determine head loss with a plant specific debris mix and screen

- Head loss concerns z Possible solutions

- Install screens with margin to handle

- Change the Buffer agent to less reactive agent

- Combination of all

After Initial Evaluations z NOTE

- Each potential solution is plant depended and can impact other aspects of the evaluation

Future issues z This is a change in the License basis for the plant

- Methods has to be in place to maintain as-built to the evaluation or evaluate any changes z Understand the evaluation z Know your margins

- Coatings nonqualified

- Latent debris

- Changes to flow balances when the throttle value openings are change.

- Changes in coating types - use generic or specific

- Changes in insulations

Future Issues Cont.

- Examples of new programs that will be needed to be put in place z Latent Debris

- Periodic surveys that monitor changes- NRC SE Requirement

- Enhancements to current containment cleanliness programs z Coatings-

- Periodic assessment be identified, described, and implemented during routine outages- NRC SE Requirements z Enhancement to Equipment /Rad Protection labeling programs

- need to understand changes to amounts

Summary z The evaluations will be completed.

z Sump screens can and will be replaced z Downstream effects will be addressed z Chemical effects will be addressed z Plants will need to understand the evaluations so they can address future issues as they occur.