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                                                                    EXHIBIT 10.1


                                 AMENDMENT NO. 3
                                       TO
                          MERGER AND PURCHASE AGREEMENT

         THIS AMENDMENT NO. 3 TO MERGER AND PURCHASE AGREEMENT (the "Third
Amendment") is made as of the 30th day of March, 1999, among Union Pacific
Resources Company, a Delaware corporation, Union Pacific Fuels, Inc., a Delaware
corporation and a wholly-owned subsidiary of Seller, Duke Energy Field Services,
Inc., a Colorado corporation, and DEFS Merger Sub Corp., a Delaware corporation
and a wholly-owned subsidiary of Buyer.

         WHEREAS, the parties hereto heretofore entered into a Merger and
Purchase Agreement, dated November 20, 1999, which was previously amended by the
First Amendment dated as of February 1, 1999 and the Second Amendment dated as
of March 5, 1999 (collectively, the "Amended Agreement") (capitalized terms not
otherwise defined herein have the same meanings ascribed to such terms in the
Amended Agreement);

         WHEREAS, the parties hereto desire to further amend the Amended
Agreement, as described below, by entering into this Third Amendment;

         NOW, THEREFORE, in consideration of the premises and of the mutual
agreements, representations, warranties, provisions and covenants herein
contained, the parties hereto hereby agree as follows:

         1. Exhibit B (Restructuring Activities) and Schedule 3.04(c)
(Capitalization) to the Amended Agreement are hereby amended and restated in
their entirety as attached hereto and new Schedules 3.01 (Qualification
Exception) and 3.04A (Assets of Certain Entities Prior to Restructuring Mergers)
are added as attached hereto.

         2. New Schedule 3.01 (Qualification Exceptions) is hereby added to the
Amended Agreement as attached hereto.

         3. Section 1.01 (Definitions) of the Amended Agreement is hereby
amended in accordance with the following:

         (a) The following new definition is hereby added:

                  "HOLDCO" means Fuels Holding Company, Inc., a newly formed
         Delaware corporation and a wholly-owned subsidiary of Seller formed
         pursuant to those Restructuring Activities contemplated by Section F of
         Exhibit B.


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         (b) The definition of the term "Subsidiary" is hereby amended and
restated in it its entirety as follows:

                  "SUBSIDIARY" means, with respect of HoldCo or the Company, as
         the case may be, any entity of which the securities or other ownership
         interests having ordinary voting power to elect a majority of the board
         of directors or other persons performing similar functions are at the
         time directly or indirectly owned by HoldCo or the Company, as the case
         may be.

         4. Section 2.01 (Merger) of the Amended Agreement is hereby amended and
restated as follows:

                  SECTION 2.01. MERGER. Subject to the terms and conditions
         hereof and in accordance with Delaware General Corporation Law (the
         "DGCL"), at the Effective Time (as hereinafter defined),

                  (a) Merger Sub, which was formed solely for purposes of
         effecting the Merger, shall be merged with and into HoldCo (the
         "MERGER") and the separate existence of Merger Sub shall cease;

                  (b) HoldCo, as the surviving corporation (also referred to
         herein as the "SURVIVING CORPORATION"), shall: (i) be a wholly-owned
         subsidiary of Buyer, (ii) continue its corporate existence under the
         laws of the State of Delaware, and (iii) succeed to all rights, assets,
         liabilities and obligations of Merger Sub and HoldCo in accordance with
         the DGCL;

                  (c) the Certificate of Incorporation of the Company, as in
         effect immediately prior to the Effective Time, as amended pursuant to
         a certificate of merger filed with respect to the Merger (the
         "CERTIFICATE OF MERGER"), shall continue as the Certificate of
         Incorporation of the Surviving Corporation until thereafter amended in
         accordance with the provisions therein and as provided by the
         applicable provisions of the DGCL;

                  (d) the By-laws of the Surviving Corporation shall be the
         By-laws of Merger Sub, as in effect immediately prior to the Effective
         Time, until thereafter amended in accordance with their terms and the
         Certificate of Incorporation of the Surviving Corporation and as
         provided by the DGCL;

                  (e) Any Shares which are held in HoldCo's treasury immediately
         prior to the Effective Time shall be canceled;



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                  (f) Each share of Merger Sub Stock which is outstanding
         immediately prior to the Effective Time shall be converted at the
         Effective Time into one share of Common Stock of the Surviving
         Corporation; and

                  (g) Each Share which is outstanding immediately prior to the
         Effective Time will be converted into, and become a right to receive,
         at the Effective Time, the amount determined by dividing the Merger
         Price by the number of Shares outstanding immediately before the
         Effective Time.

         5. Section 2.03(c) of the Amended Agreement is hereby amended and
restated as follows:

                  (c) The parties hereto shall cause the Merger to be
         consummated by filing the Certificate of Merger with the Secretary of
         State of the State of Delaware in such form as required by, and
         executed in accordance with the relevant provisions of, Delaware Law,
         and the Certificate of Merger shall provide for an effective time of
         the Merger of 11:59 p.m., central time on March 31, 1999 (such time
         being referred to herein as the "EFFECTIVE TIME").

         6. Part A of ARTICLE 3 (Representations and Warranties of Seller) of
the Amended Agreement is hereby amended in accordance with the following:

         (a) Section 3.01 (Corporate Existence and Power of the Company) of the
Amended Agreement is hereby amended and restated as follows:

                  SECTION 3.01 EXISTENCE AND POWER OF HOLDCO AND THE COMPANY.
         (a) Each of the Company and its Subsidiaries is duly incorporated (or
         otherwise organized or formed, in the case of non-corporate
         Subsidiaries or the Company following the Company Restructuring
         Merger), validly existing and in good standing under the laws of the
         state of its incorporation (or organization or formation, in the case
         of non-corporate Subsidiaries or the Company following the Company
         Restructuring Merger), and has all corporate (or partnership or
         company, in the case of non-corporate Subsidiaries or the Company
         following the Company Restructuring Merger) powers required to carry on
         its business as now conducted. Except as set forth on Schedule 3.01
         hereto, the Company and each Subsidiary is duly qualified to do
         business in each jurisdiction where such qualification is necessary to
         the business of the Company or such Subsidiary. Seller has heretofore
         delivered to Buyer true and complete copies of the charter and bylaws
         (or comparable organizational documents with respect to non-corporate
         entities) of the Company and each of its Subsidiaries as currently in
         effect.

                  (b) By the Closing, HoldCo will have been duly incorporated
         and will be validly existing and in good standing under the laws of the
         state of its incorporation, and will have all corporate powers required
         to carry on its business as then being conducted. 


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         (b) Section 3.04 (Capitalization) of the Amended Agreement is hereby
amended and restated as follows:

         SECTION 3.04 CAPITALIZATION. (a) The authorized capital stock of HoldCo
         consists of 1,000 shares of Common Stock (the "SHARES"). At the
         Closing, no capital stock of HoldCo other than the Shares will be
         outstanding. The Shares have been duly authorized and validly issued
         and are fully paid and non-assessable.

                  (b) Except for the Shares, at the Closing there will be
         outstanding no (i) shares of capital stock or other voting securities
         of HoldCo, (ii) securities of HoldCo convertible into or exchangeable
         for shares of capital stock or voting securities of HoldCo or (iii)
         options or other rights to acquire from HoldCo, and there is no
         obligation of HoldCo to issue, any capital stock, voting securities or
         securities convertible into or exchangeable for capital stock or voting
         securities (the items in clauses (i), (ii) and (iii) being referred to
         collectively as the "HOLDCO SECURITIES")

                  (c) Schedule 3.04(c) sets forth a list of all of the
         Subsidiaries of HoldCo (including the Company and its Subsidiaries)
         upon completion of the Restructuring Activities. Except as set forth on
         Schedule 3.04(c), all of the outstanding capital stock of, or other
         voting securities or ownership interests in, each Subsidiary of HoldCo,
         have been duly authorized and validly issued and are fully paid and
         non-assessable, and are owned by HoldCo, directly or indirectly, free
         and clear of any Lien and free of any other limitation or restriction
         (other than those created by this Agreement and restrictions on sales
         of stock under applicable securities laws), including any restriction
         on the right to vote, sell or otherwise dispose of such capital stock
         or other voting securities or ownership interests. There are no
         outstanding (i) securities of HoldCo or any of its Subsidiaries
         convertible into or exchangeable for shares of capital stock or other
         voting securities or ownership interests in any such Subsidiary or (ii)
         options or other rights to acquire from HoldCo or any of its
         Subsidiaries, or other obligation of HoldCo or any of its Subsidiaries
         to issue, any capital stock or other voting securities or ownership
         interests in, or any securities convertible into or exchangeable for
         any capital stock or other voting securities or ownership interests in,
         any Subsidiary of HoldCo (the items in clauses (i) and (ii) being
         referred to collectively as the "SUBSIDIARY SECURITIES"). There are no
         outstanding obligations of HoldCo or any of its Subsidiaries to
         repurchase, redeem or otherwise acquire any outstanding HoldCo
         Securities or Subsidiary Securities.

         (c) The following new Section 3.04A (Assets of Certain New Entities) is
hereby added:

         SECTION 3.04A ASSETS OF CERTAIN NEW ENTITIES. The entities identified
         on Schedule 3.04A will have been created solely for purposes of
         effecting the Restructuring Mergers, and in the case of HoldCo, the
         Merger, and as such, as of immediately before the Restructuring
         Mergers, will not (i) have engaged in any business operations, (ii)
         have



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         incurred any liabilities of any kind, or (iii) own any assets (other
         than those identified on Schedule 3.04A hereto).

         7. The following sentence shall be added to Section 12.02(a) of the
Amended Agreement:

         The Material Adverse Effect qualification otherwise applicable in
         respect of the representation and warranty of Seller contained in
         clause (iii) of Section 3.03 and the limitations on indemnity claims
         set forth in Section 12.03(b)(ii), shall not apply if (A) there is a
         breach of such representation and warranty, which results from the
         merger of the Company with and into Union Pacific Fuels, L.P., as
         contemplated by Section F of Exhibit B hereto, and (B) no such breach
         would have resulted if the Company, rather than Union Pacific Fuels,
         L.P., was the surviving entity in such merger.

         8. The Parties acknowledge that pursuant to those Restructuring
Activities contemplated by Section F of Exhibit B hereto, prior to the Closing:
(i) the Company will be merged (such merger being referred to as the "COMPANY
RESTRUCTURING MERGER") with and into a Union Pacific Fuels, L.P., a Delaware
limited partnership of which HoldCo will be the 99.5% limited partner and Fuels
Holding Company Operating LLC, a Delaware limited liability company (of which
HoldCo will be the sole member), will be the 0.5% general partner, and (ii) each
of Fuels Acquisition Company, Peach Ridge Pipeline, Inc. and Panola Pipe Line,
Inc. (collectively, the "CONVERTED SUBSIDIARIES"), respectively, will be merged
with and into Fuels Acquisition Company, L.P., Peach Ridge Pipeline, L.P., and
Panola Pipe Line, L.P., respectively, which are all Delaware limited
partnerships, the partnership interests of which will at Closing be held by
Subsidiaries of HoldCo (the mergers involving the Converted Subsidiaries are
referred to herein, together with the Company Restructuring Merger, as the
"RESTRUCTURING MERGERS"). In light of the foregoing, any representation,
covenant or other provision in the Amended Agreement (other than those
specifically amended and restated pursuant to Section 5 above) containing a
reference to "the Company" shall be deemed appropriately modified so that
following the completion of such Restructuring Activities such reference shall
relate to the Delaware limited partnership survivor of the Company Restructuring
Merger.

         9. This Third Amendment is executed, and shall be considered, as an
amendment to the Amended Agreement and shall form a part thereof, and the
provisions of the Amended Agreement, as amended by this Third Amendment, are
hereby ratified and confirmed in all respects.

         10. This Third Amendment may be executed in any number of counterparts,
each of which shall be deemed an original, and all of which taken together shall
constitute but one and the same instrument. This Third Amendment shall become
binding only when each party hereto has executed and delivered to the other
parties one or more counterparts.

                           [intentionally left blank]



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         IN WITNESS WHEREOF, the parties hereto have executed this Third
Amendment or have caused this Third Amendment to be duly executed by their
respective authorized officers as of the day and year first above written.


                         UNION PACIFIC RESOURCES COMPANY



                         By:  /s/ JOSEPH A. LASALA
                            ----------------------------------------------------
                            Name:  Joseph A. LaSala
                            Title: Vice President, General Counsel
                                   and Corporate Secretary



                         UNION PACIFIC FUELS, INC.



                         By:  /s/ KERRY R. BRITTAIN
                            ----------------------------------------------------
                            Name:  Kerry R. Brittain
                            Title: Vice President




                         DUKE ENERGY FIELD SERVICES, INC.


                         By:  /s/ DAVID D. FREDERICK
                            ----------------------------------------------------
                            Name:  David D. Frederick
                            Title: Senior Vice President



                         DEFS MERGER SUB CORP.


                         By:  /s/ DAVID D. FREDERICK
                            ----------------------------------------------------
                            Name:  David D. Frederick
                            Title: Senior Vice President


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