NOTICE DATE:  June 30, 2009

NOTICE TYPE:  M-B063009-01 Operations

SHORT DESCRIPTION: ERCOT/ONCOR has developed a system equipment status change which was implemented at 5:10 PM on Monday, June 29, 2009

INTENDED AUDIENCE:  All Market Participants

DAY AFFECTED:  5:10 PM Monday, June 29, 2009, through 8:00 AM Tuesday, September 1, 2009

LONG DESCRIPTION:  ERCOT has requested that ONCOR open the 138 kV line from Waco West to Temple Elm Creek at Cotton Belt. This equipment status change is for the Waco area in response to the system needs in managing the North to South Commercially Significant Constraint (CSC) transfer and to mitigate the constraint on the North to South CSC in response to the recent high temperatures.

As a result, the 69 kV lines from Waco West to McGregor TU and from Waco West to Temple will be radial during this period.

ADDITIONAL INFORMATION:  This change is effective through September 1, 2009. During forced outages or extreme weather in the affected area, the lines may be required to be connected for support or restoring load.

The equipment which will change is listed at: http://mospublic.ercot.com/ercot/jsp/planned_trans_out.jsp and was posted at 5:13 PM June 29, 2009.

Additionally, this switching is expected to improve North to South transfer capability by as much as 200 MW, which will aid ERCOT in reliably managing transfers North to South.

CONTACT:  If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via e-mail at [log in to unmask].

If you are receiving e-mail from an ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list: http://lists.ercot.com.

ad/dh