1. Bulk Electric System Definition Task Force Update Reliability Policy Issues Committee April 28, 2010 Brian Theaker BESDTF Chair

2. Todays Update FERC BES NOPR Proposals 4 & 5 Material Impact Assessment Schedule Questions 1.2

3. FERC BES NOPR NERC to modify BES definition to eliminate RE discretion Allow for NERC/FERC-approved facility exclusion Consistent with BESDTF direction Comments due 5/10 BESDTF will provide input to WECC comments Exemptions: Method vs. facility by facility 1.3

4. Proposal 4 Comments focused on: Distribution Network exclusion General support, but cannot define Points of demarcation Support, want detailed examples Exclusion for non-represented Elements Split, no consensus 1.4

5. Material Impact Assessment March 30 BES/TSS/WECC meeting Some progress: General consensus around significant impact test Further thinking around widespread impact test Electrical dispersion of indicator buses Additional work needed from TSS Consensus principles articulated 1.5

6. Schedule April 16: Response to comments on P4 April 28-30: TSS recommendation on MIA May 7: Post P5 with MIA (45-day) June 10-11: Update to OC July/August: Additional proposal/comments September 21: Post proposal for OC approval October 21-22: OC consideration December 8-10: Board consideration 1.6

7. Questions? For every complex problem there is an answer that is clear, simple, and wrong. H.L. Mencken Things should be made as simple as possible, but not any simpler. Albert Einstein Brian Theaker Chair, BESDTF brian.theaker@dynegy.com