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                                                                    EXHIBIT 10.4

                        AMENDMENT TO SERVICE AGREEMENT

     THIS AMENDMENT ("Amendment") is entered into this 15th day of December
1997, by and between TRANSCONTINENTAL GAS PIPE LINE CORPORATION, a Delaware
corporation, hereinafter referred to as "Seller", first party, and ATLANTA GAS
LIGHT COMPANY, hereinafter referred to as "Buyer", second party.

                                  WITNESSETH:

     WHEREAS, Seller and Buyer entered into that certain Service Agreement,
dated August 16, 1974, under Seller's Rate Schedule LG-A ("Service Agreement")
pursuant to which Seller provides liquefied natural gas storage service for
Buyer up to a total volume of 207,610 Mcf of natural gas which is Buyer's
Liquefaction Capacity Volume; and

     WHEREAS, Seller and Buyer now desire to renew and extend the primary term
of the Service Agreement.

     NOW THEREFORE, Seller and Buyer hereby agree to renew and amend the Service
Agreement as follows.

1.   Article IV of the Service Agreement is hereby deleted in its entirety and
     replaced by the following:

                                  "ARTICLE IV
                               TERM OF AGREEMENT

     This agreement shall be effective as of November 1, 1974 and shall remain
     in force and effect until 8:00 a.m. Eastern Standard Time October 31,
     2002/1/, and thereafter until terminated by Seller or Buyer upon at least
     one hundred eighty (180) days prior written notice and subject to the
     receipt of necessary authorizations; provided, however, this agreement
     shall terminate immediately and, subject to the receipt of necessary
     authorizations, Seller may discontinue service hereunder if (a) Buyer, in
     Seller's reasonable judgement fails to demonstrate creditworthiness, and
     (b) Buyer fails to provide adequate security in accordance with Section 32
     of the General Terms and Conditions of Seller's Volume No. 1 Tariff."

2.   As herein amended, the Service Agreement is hereby renewed in full force
     and effect pursuant to the terms thereof.

3.   This Amendment shall be effective as of the date first above written.

_________________

     /1/The parties hereto mutually acknowledge that the term of this agreement
is the result of a negotiated compromise between Buyer and Seller and shall not
be relied upon by either party as precedent for any future contract term
negotiation for this or any other service provided by Seller. Further, the term
of this agreement shall not be raised by either party in any proceeding before
the FERC as having established any precedent whatsoever to the length of
contract terms.


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LG-A Amendment
Page 2


     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
signed by their respective officers or representatives thereunto duly
authorized.


TRANSCONTINENTAL GAS PIPE                         ATLANTA GAS LIGHT COMPANY
LINE CORPORATION ("Seller")                       ("Buyer")


By  /s/ Frank J. Ferazzi                          By
  -------------------------                         -------------------------

  Frank J. Ferazzi
  Vice President                                  Title______________________
  Customer Service