Southwest Gas Storage Company

First Revised Volume No. 1

Effective Date: 09/22/2004, Docket: RP04-481-000, Status: Effective

Third Revised Sheet No. 138 Third Revised Sheet No. 138 : Effective

Superseding: Second Revised Sheet No. 138

GENERAL TERMS AND CONDITIONS

(Continued)

11. ELECTRONIC COMMUNICATION SYSTEM (Continued)

11.4 Through the Messenger system the User may obtain:

(A) Information concerning the availability of capacity for firm

storage services in the Storage Fields, and whether the

capacity is available from Southwest directly, through

exercise of Shipper's right of first refusal, or through

capacity release.

(B) A listing of Points of Receipt and Points of Delivery on

Southwest's system.

11.5 Electronic data interchange will be available on a

nondiscriminatory basis to any party. A mutually acceptable

agreement between Southwest and such party is required for

electronic transmission of data.

11.6 Any provisions of this FERC Gas Tariff requiring that matters be

written or in writing, including the execution of Storage Service

Agreements or amendments, are satisfied by utilizing electronic

transmission through the Messenger system in accordance with the

procedures for utilization of the Messenger system or electronic

data interchange as provided for in the Commission approved or

permitted data sets. All other provisions requiring items or

information to be written or in writing remain unchanged.

11.7 Should Southwest invalidate any password or USERID due to breach

of confidentiality or unauthorized use of the Messenger system,

pursuant to the Messenger Service Agreement, Southwest shall

provide the Messenger User with notice and reason for the

invalidation.