Southwest Gas Storage Company

First Revised Volume No. 1

Effective Date: 05/17/2009, Docket: RP09-514-000, Status: Effective

Fourth Revised Sheet No. 137 Fourth Revised Sheet No. 137

Superseding: Third Revised Sheet No. 137

GENERAL TERMS AND CONDITIONS

(Continued)

11. ELECTRONIC COMMUNICATION SYSTEM

11.1 Southwest has established an electronic communication system, the

Messenger® system, for use by any party, including Shippers and

potential Shippers. The Messenger® system will be available on a

nondiscriminatory basis to any party (hereinafter the "User") that

has compatible equipment for electronic transmission of data,

provided that such party executes a Messenger® Service Agreement

in the form prescribed in this Tariff, has been assigned a user

identification (USERID) and password, and agrees to comply with

the procedures for use of the Messenger® system. Southwest shall

provide timely and equal access to information available on the

Messenger® system.

11.2 The Messenger® system will provide on-line help, a search function

that permits Users to locate all information concerning a specific

transaction, and menus that permit Users to access separately each

record in the capacity allocation log, notices of available

capacity, affiliate and standards of conduct information. The

Messenger® system will permit Users to electronically download a

file from the Messenger® system and to split files into smaller

files prior to such download. Information on the most recent

entries shall appear ahead of older information. Southwest will

purge completed transactions from current Messenger® system files

after they have been posted for a minimum of ninety (90) days.

Information that has been purged from the Messenger® system will be

archived and may be retrieved from archives and made available in

written or electronic format.

11.3 The Messenger® system may be used to interactively: (a) execute

or amend Storage Service Agreements, and provide and confirm

nominations pursuant to the applicable Rate Schedule and these

General Terms and Conditions; (b) execute a right of first

refusal as an existing Shipper pursuant to Section 8 herein or

submit a bid as a potential Shipper under Sections 6 or 7; (c)

release capacity pursuant to Section 6 herein and (d) post a

request for capacity pursuant to Section 6 or Section 7.