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                                                                EXHIBIT 10.28(f)

                   MINI-MED/DENTAL BENEFIT EXTENSION AGREEMENT

         THIS AGREEMENT is entered into effective as of the 1st day of October
1994 (the "Effective Date") by and between ATMOS ENERGY CORPORATION, a Texas
corporation (the "Company") and CHARLES K. VAUGHAN ("Mr. Vaughan").

                                    RECITALS

         A. Mr. Vaughn is presently a participant in the Atmos Energy
Corporation Mini-Med Plan (the "Mini-Med Plan") and, as an active employee of
the Company, participates in the Company's Group Dental Plan (the "Dental
Plan").

         B. Mr. Vaughn desires to retire from the employ of the Company, but as
a retiree may no longer be eligible for participation in the Mini-Med Plan or
the Dental Plan.

         C. The Company, in consideration of Mr. Vaughan's long and valuable
service to the Company, has agreed to provide Mr. Vaughan with the benefits of
the Mini-Med Plan and the Dental Plan.

         NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree as follows:

                  1. Benefits Provided to Mr. Vaughan. From and after the
Effective Date, and for the term of this Agreement, the Company shall pay to Mr.
Vaughan, in cash (a) the benefits he (and his eligible dependents) would be
entitled to under the terms of the Mini-Med Plan, as in effect from time to time
during the term of this Agreement, if Mr. Vaughan continued to be a participant
in the Mini-Med Plan and if he remained a participant in the Dental Plan, but in
no event less than the benefits provided under the terms of the Mini-Med Plan as
in effect on the Effective Date, and (b) the benefits Mr. Vaughan (and his
eligible dependents) would be entitled to under the Dental Plan, as in effect
from time to time during the term of this Agreement, if Mr. Vaughan had remained
an employee of the Company through the term of this Agreement, but in no event
less than the benefits provided under the terms of the Dental Plan as in effect
on the Effective Date.

                  2. Benefits Provided to Mr. Vaughan's Surviving Spouse. If Mr.
Vaughan dies prior to reaching age 65 and leaves a surviving spouse, said spouse
shall, for the balance of the term of this Agreement, be entitled to the
benefits being provided to Mr. Vaughan under Section 1 hereof, as if Mr. Vaughan
had not died.

                  3. Term of the Agreement. Except as otherwise provided in this
Section 3, the term of this Agreement shall commence on the Effective Date and
shall

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end on the earlier of the date Mr. Vaughan reaches age 65, or the date he dies.
Notwithstanding the foregoing provisions of this Section 3, in the event Mr.
Vaughan dies prior to reaching age 65 and leaves a surviving spouse, the term of
this Agreement shall end on the earlier of the date such surviving spouse dies
or remarries, or the date Mr. Vaughan would have attained age 65.

                  4. Procedure for Receipt of Benefits. In order to receive the
benefits provided in this Agreement, Mr. Vaughan, or his surviving spouse, shall
present claims for those benefits on the same forms as if he was participating
in the Mini-Med Plan or the Dental Plan, as the case may be, but shall submit
such claims to the Vice President-Human Resources.

                  5. Entire Agreement. This Agreement embodies the entire
understanding between the parties hereto respecting the subject matter hereof,
and no change, alteration or modification may be made except by authorization of
the Board of Directors of the Company and except in writing signed by both
parties hereto.

                  6. Controlling Law. This Agreement shall in all respects be
construed and enforced in accordance with the laws of the State of Texas.

                  7. Payment of Legal Fees. The Company agrees to pay any and
all legal fees and expenses incurred by Mr. Vaughan or his surviving spouse in
seeking to obtain any of the benefits or enforce any of the provisions of this
Agreement.

                  8. Successors and Assigns. Any successor to the Company shall
be bound by the terms of this Agreement in the same manner and to the same
extent as the Company, and this Agreement shall be binding upon Mr. Vaughan, his
heirs and legal representatives.

         IN WITNESS WHEREOF, the Company and Mr. Vaughan have each duly executed
this Agreement the 30th day of October, 1994, effective as of the date and year
first written above.

                                        COMPANY:

                                        ATMOS ENERGY CORPORATION

                                        By: /s/ DEWEY G. WILLIAMS
                                            -----------------------------------
                                            Dewey G. Williams
                                            Chairman, Human Resources
                                            Committee of the Board of Directors


                                            /s/ CHARLES K. VAUGHAN
                                            -----------------------------------
                                            Charles K. Vaughan