Transco’s Post Cycle Customer Testing and Training Packet Overview

1. Transco’s Post Cycle Customer Testing and Training Packet Overview scheduled implementation in 1Line: May 2, 2007 for May 1, 2007 business • In response to customer requests to incorporate additional flexibility into the 1Line nomination process, Transco is implementing a new nomination/confirmation cycle following the existing Intraday 2 cycle, called the Post Cycle. Using the Post Cycle, customers are able to submit nominations and PDAs for the ‘just completed gas day’, subject to explicit confirmation by the upstream and downstream operators. • In addition to the new Post Cycle, Transco has made the ‘MDQ Calculate’ feature on the Nominations page available for all days. • This packet contains the following: • Nomination/Confirmation Timelines (CCT) • Critical Requirements • Critical Requirements: Confirmation Scenarios • Sample Customer Test Plan • To access other Post Cycle information previously provided, please click below. October 18, 2006 EBB Posting January 19, 2007 EBB Posting

2. Transco’s Post Cycle Nomination / Confirmation Timelineseffective 5/2/2007 for 5/1/2007business (CCT) Calendar Day One - 12:00 AM – 12:00 AM (24 hr period) Calendar Day Two Gas Day One - 9:00 AM – 9:00 AM (24 hr period) 12:00 AM 12:00 PM / / 10:00 8:00 9:00 10:00 11:00 1:00 2:00 3:00 4:00 5:00 6:00 7:00 8:00 9:00 10:00 11:00 9:00 11:00 12:00 Post Cycle10:00 AM-11:30 AM Intraday 2 NominationsGas scheduled and flowing by 9:00 PM on Gas Day 1. Intraday 2 Nomination Cycle5:00 PM–9:00 PM Intraday 1 Nomination Cycle10:00 AM – 2:00 PM Timely Gas Nomination Cycle11:30 AM–4:30 PM Timely NominationsSent by 11:30AM Evening Nomination Cycle6:00 PM–10:00 PM Post NominationsFinal Schedule Quantity by11:30 AM for Gas Day 1 Intraday 1 NominationsGas scheduled by 2:00 PM for 5:00 PM flow on Gas Day 1 Evening NominationsGas scheduled by 10:00 PM for 9:00 AM flow on Gas Day 2 Timely NominationsGas scheduled by 4:30 PM for 9:00 AM flow on Gas Day 2 New Post Cycle Timelines 10:00 AM – Nomination Deadline 10:30 AM – Confirmation and PDA Deadline 11:30 AM – Final Schedule Quantity Reports Available

3. Transco’s Post Cycle Critical Requirements • Use of the Post Cycle is optional • To use the Post Cycle successfully, please be advised: • Action is Requiredof the location operators and any upstream or downstream entities for changes to ID2 data to become effective. • Rolling Nominations and Confirmations will not be used; Auto Confirmations are automatically set to OFF. • Pool tolerance will be 0% when the Post Cycle is used i.e. Supply Disaggregation, Market and the applicable confirmations must match exactly. • No previously scheduled quantity will be reduced unless nominated and confirmed. • Customers can go below EPSQ with approval from all parties. • Confirming parties must explicitly confirm, unless: • Shipper and Operator are equal (self confirmation applies) • The quantity confirmed at the ID2 aggregate level = the Post Cycle aggregate level quantity

4. Transco’s Post Cycle Critical Requirements: Confirmation Scenarios • Although confirmations can be made at all levels, confirming gas at the transaction level is strongly recommended because all parties involved in an aggregate transaction may not confirm: • Confirming gas at the transaction level during the Post Cycle limits the possibility of one transaction affecting another transaction, as shown. • Nomination will revert to the ID2 nomination if all elements in a transaction are not in place. Delivery 1 50 dt • Example 1: Confirmations at the Aggregate Level: • Assumptions: • Receipt Point Operator confirms 100 dt at the aggregate level • Delivery Point Operator #1 confirms 50 dt • 50 dt is nominated at Delivery Point #2, but the Operator does not confirm • Outcome: Unsuccessful Results: All noms revert back to ID2 Receipt 1 100 dt Delivery 2 50 dt Receipt 1 50 dt Delivery 1 50 dt • Example 2: Confirmations at the Transaction Level (Strongly Recommended): • Assumptions: • Receipt Point Operator confirms both transactions at the transaction level for • 50 dt each, or a total confirmation of 100 dt • Delivery Point Operator #1 confirms 50 dt • 50 dt is nominated at Delivery Point #2, but the Operator does not confirm • Outcome: Successful results for the first transaction: • Nominated, Confirmed and Scheduled during the Post Cycle at 50 dt • Outcome: Unsuccessful results for the second transaction: • All noms revert back to ID2 Receipt 2 50 dt Delivery 2 50 dt

5. Transco’s Post Cycle Sample Customer Test Plan • To facilitate a smooth transition in using the Post Cycle 1/, the following customer test plan is recommended: • The test environment is available as of 4/16/07. Customers use their existing 1Line User ID. For security reasons, customers must first call their Transportation Services rep to have their testing password reset. • Once you have called your Transportation Services rep and have your new testing password, access the training environment by going to > www.1linetraining.williams.com. On your initial sign-on, you may be asked to accept the 1Line Testing and Training Agreement. • The data loaded into the testing environment is current as of Monday, April 9, 2007. Customers should see existing transactions from their day-to-day business. • On a given day, before or by 10:00 a.m. 2/, select an existing April 2007 transaction. Nominate a change to the transaction for the previous gas day. At the same time, confirm any transactions allowed by 1Line. • Immediately contact your Transportation Services rep and request manual confirmation of any additional locations by 10:30 a.m. • Verify your revised transaction(s) as early as 11:30 a.m. using the SQR or online using 1Line Scheduling pages. • Questions? Contact your Transportation Services representative. • Notes: • 1/ All times are expressed as CCT • 2/ Post Cycle changes can be done as early at 5:15 p.m. the day of flow (after the ID2 cycle closes)