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                                                                 EXHIBIT 10.8(b)

                                 FIRST AMENDMENT
                                       TO
                            PARENT COMPANY AGREEMENT

         This First Amendment to Parent Company Agreement (this "Amendment"),
dated as of May 25, 2000, is entered into by and among Phillips Petroleum
Company, a Delaware corporation ("Phillips"), Duke Energy Corporation, a North
Carolina corporation ("Duke"), Duke Energy Field Services, LLC, a Delaware
limited liability company (the "Company") and Duke Energy Field Services
Corporation, a Delaware corporation ("DEFS").

         WHEREAS, reference is made to that certain Parent Company Agreement by
and among Phillips, Duke, the Company and DEFS dated as of March 31, 2000 (the
"Parent Company Agreement"); and

         WHEREAS, Phillips, Duke, the Company and DEFS desire to amend the
Parent Company Agreement;

         NOW, THEREFORE, for and in consideration of the mutual benefits to be
derived from this Amendment, and intending to be legally bound hereby, the
parties hereto hereby agree as follows:

         Section 1.   AMENDMENTS TO PARENT COMPANY AGREEMENT. The Parent Company
Agreement is hereby amended as follows:

                  (a) The definition of "Average Market Price" in Section 1.1 of
         the Parent Company Agreement and in Exhibit C ("Terms of PGCSI Parent
         Rights") and Exhibit D ("Terms of DENG Rights") to Exhibit A
         ("Agreement of Merger of Phillips Gas Company Shareholder, Inc. with
         and into Duke Energy Field Services Corporation") to the Parent Company
         Agreement is hereby amended by adding at the end of such definition in
         each instance after the phrase "(exclusive of the pricing day)" the
         following:

                  "; provided, that, if the IPO is consummated on or before June
                  24, 2000, then (x) if the IPO Price is greater than or equal
                  to $20 per share, the Average Market Price shall not be below
                  the Floor Price or in excess of the Ceiling Price and (y) if
                  the IPO Price is less than $20 per share, the Average Market
                  Price shall be equal to the IPO Price. "Floor Price" shall
                  mean the IPO Price minus $1 per share. "Ceiling Price" shall
                  mean the IPO Price plus $1 per share. "IPO Price" shall mean
                  the public offering price per share of the Corporation Common
                  Stock in the IPO."

                  (b) Item 2 of Annex A ("Super-Majority Items") to Exhibit B
         ("Amended and Restated Bylaws of Duke Energy Field Services
         Corporation") to Exhibit A ("Agreement of Merger of Phillips Gas
         Company Shareholder, Inc. with and into Duke Energy Field Services
         Corporation") to the Parent Company Agreement is amended by deleting it
         in its entirety and inserting the following in replacement therefor:

                  "2. Entering a new line of business outside of the midstream
                  gas gathering, processing, transportation and marketing
                  businesses (and directly related activities)



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                  in the United States and Canada, the marketing of natural gas
                  liquids in Mexico, the transportation of refined petroleum
                  products and liquefied petroleum gases and related products
                  and related terminaling, storage and other activities, and the
                  gathering, transportation, storage and marketing of crude
                  oil."

                  (c) Item 1 of Exhibit B ("Phillips Veto Actions") to Exhibit B
         ("Shareholders Agreement by and among Duke Energy Natural Gas
         Corporation and Phillips Petroleum Company") to the Parent Company
         Agreement is amended by deleting it in its entirety and inserting the
         following in replacement therefor:

                  "1. Entering a new line of business outside of the midstream
                  gas gathering, processing, transportation and marketing
                  businesses (and directly related activities) in the United
                  States and Canada, the marketing of natural gas liquids in
                  Mexico, the transportation of refined petroleum products and
                  liquefied petroleum gases and related products and related
                  terminaling, storage and other activities, and the gathering,
                  transportation, storage and marketing of crude oil."

         Section 2.   MISCELLANEOUS.

                  (a) Counterparts. This Amendment may be executed in one or
         more counterparts, all of which shall be considered one and the same
         agreement, and shall become effective when one or more counterparts
         have been signed by each of the parties hereto and delivered (including
         by facsimile) to the other party.

                  (b) Incorporation. The provisions of Sections 8.2 through 8.12
         of the Parent Company Agreement are hereby incorporated herein and
         shall be deemed to include and/or apply to this Amendment, as
         appropriate.

                  (c) Ratification. Except as amended hereby, the Parent Company
         Agreement shall remain in full force and effect as previously executed
         by the parties, and the parties hereby ratify the Parent Company
         Agreement as amended hereby.



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         IN WITNESS WHEREOF, each of the undersigned, intending to be legally
bound, has caused this Amendment to be duly executed and delivered on the date
first set forth above.


                                         PHILLIPS PETROLEUM COMPANY

                                         By: /s/ JOHN A. CARRIG, SR.
                                            ------------------------------------
                                         Name:   John A. Carrig, Sr.
                                              ----------------------------------
                                         Title:  Vice President and Treasurer
                                               ---------------------------------


                                         DUKE ENERGY CORPORATION

                                         By: /s/ RICHARD McGEE
                                            ------------------------------------
                                         Name:   Richard McGee
                                              ----------------------------------
                                         Title:  Vice President
                                               ---------------------------------


                                         DUKE ENERGY FIELD SERVICES, LLC

                                         By: /s/ MARTHA B. WYRSCH
                                            ------------------------------------
                                         Name:   Martha B. Wyrsch
                                              ----------------------------------
                                         Title:  Senior Vice President-
                                                   General Counsel and Secretary
                                               ---------------------------------



                                         DUKE ENERGY FIELD SERVICES CORPORATION

                                         By: /s/ MARTHA B. WYRSCH
                                            ------------------------------------
                                         Name:   Martha B. Wyrsch
                                              ----------------------------------
                                         Title:  Senior Vice President-
                                                   General Counsel and Secretary
                                               ---------------------------------










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