[LETTERHEAD]


December 15, 1998


Mr. Bud Foster
Texstar Petroleum, Inc.
1000 Louisiana, Suite 3950
Houston, Texas 77002


RE:  Sale of Wausau Pipeline System, A. Foote Estate #1 and Fairchild #1 Wells
     Wayne and Jones Counties, Mississippi


Dear Mr. Foster:

     Reference is made to the December 14, 1998 letter of intent by Texstar
offering to purchase the TransTexas eight-inch pipeline, and related
facilities, running from the TransTexas Foote Estate #1 well in Wayne County,
Mississippi to the Tennessee Gas Transmission Line in Jones County,
Mississippi, and the TransTexas A. Foote Estate #1 and Fairchild #1 wells.

     TransTexas is interested in selling the pipeline and wells subject to
general terms and conditions stated in your letter of intent, but altered as
set forth below:

     (i)    Cash consideration for the pipeline and wells in the amount of
            Four Hundred Twenty-five Thousand Dollars ($425,000) for
            TransTexas' right, title and interest (assumed to be 100% in the
            pipeline and a net revenue interest of 70% in each well);

     (ii)   Free gas transportation as set forth in paragraph 3 of your
            letter of intent is no longer necessary because Texstar will be
            buying the wells;

     (iii)  The execution by both parties of definitive conveyancing
            documents which set forth mutually acceptable terms and
            conditions of the transaction; and

     (iv)   The approval by the Board of Directors of TransTexas Gas
            Corporation.

     If the foregoing alterations to the provisions set forth in the Texstar
December 14, 1998 letter of intent represent acceptable revised general terms
and conditions for the purchase and sale of these assets, please sign in the
space provided below and return one executed copy to TransTexas.

                                       Very truly yours,

                                       /s/ Arnold Brackenridge
                                       ---------------------------------------
                                           Arnold Brackenridge
                                           President


AGREED TO AND ACCEPTED:

/s/ William G. Foster
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William G. Foster, Land Manager