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                                                                    EXHIBIT 10.6

                                                           Draft of June 4, 2001


                CONTRIBUTION, ASSIGNMENT AND AMENDMENT AGREEMENT

     This CONTRIBUTION, ASSIGNMENT AND AMENDMENT AGREEMENT is made as of June 8,
2001, between Plains All American Inc., a Delaware corporation (the "DEPARTING
GP"), Plains AAP, L.P., a Delaware limited partnership (the "GP LP") and Plains
All American GP LLC, a Delaware limited liability company ("SUCCESSOR GP LLC").
Capitalized terms used and not otherwise defined herein shall have the
respective meanings ascribed to such terms in the Investor Agreements (as
defined below).

                                    RECITALS

          WHEREAS, the Departing GP has entered into a Unit Transfer and
Contribution Agreement, dated as of May 8, 2001, as amended (the "KAFU
AGREEMENT"), among Kafu Holdings, LLC, Plains Resources Inc. ("PARENT"), the
Departing GP and PAAI LLC ("SELLER");

          WHEREAS, the Departing GP has entered into a Unit Transfer and
Contribution Agreement, dated as of May 8, 2001 (the "SABLE AGREEMENT"), among
Sable Investments, L.P., Sable Holdings, L.P., James C. Flores, Parent, the
Departing GP and Seller;

          WHEREAS, the Departing GP has entered into a Unit Transfer and
Contribution Agreement, dated as of May 8, 2001, as amended (the "ENCAP
AGREEMENT"), among E-Holdings III, L.P., Parent, the Departing GP and Seller;

          WHEREAS, the Departing GP has entered into a Unit Transfer and
Contribution Agreement, dated as of June 8, 2001 ( the "RAYMOND AGREEMENT")
among John T. Raymond, Parent, the Departing GP and Seller;

          WHEREAS, the Departing GP has entered into a Unit Transfer and
Contribution Agreement, dated as of June 8, 2001 (the "STROME AGREEMENT") among
Mark E. Strome, Parent, the Departing GP and Seller;

          WHEREAS, the Departing GP has entered into a Unit Transfer and
Contribution Agreement, dated as of June 8, 2001 (the "STROME HEDGECAP FUND
AGREEMENT") among Strome Hedgecap Fund L.P., Parent, the Departing GP and
Seller;

          WHEREAS, the Departing GP has entered into a Contribution Agreement,
dated as of June 8, 2001 (the "MANAGEMENT ENTITY CONTRIBUTION AGREEMENT" and
together with the Kafu Agreement, the Sable Agreement, the EnCap Agreement, the
Raymond Agreement, the Strome Agreement and the Strome Hedgecap Fund Agreement,
the "INVESTOR AGREEMENTS") among PAA Management, L.P., Parent and the Departing
GP;

          WHEREAS, the Departing GP has agreed, as a condition to the closing of
the transactions contemplated by the Investor Agreements, to contribute the LLC
Incentive Distribution Rights to Successor GP LLC as its capital contribution as
a member of Successor GP LLC;

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          WHEREAS, Successor GP LLC has agreed, as a condition to the closing of
the transactions contemplated by the Investor Agreements, to contribute the LLC
Incentive Distribution Rights to the GP LP as its capital contribution as the
general partner of the GP LP;

          WHEREAS, the Departing GP has agreed, as a condition to the closing of
the transactions contemplated by the Investor Agreements, to contribute, among
other things, the GP Interest, the Operating Partnerships GP Interests and the
LP Incentive Distribution Rights to the GP LP as its capital contribution as the
GP LP's limited partner;

          WHEREAS, the GP LP desires to assume the rights and duties of the
general partner of Plains All American Pipeline, L.P. (the "PARTNERSHIP") and
the Operating Partnerships and to be bound by the provisions of the Second
Amended and Restated Agreement of Limited Partnership of the Partnership dated
as of November 23, 1998, as amended (the "PARTNERSHIP AGREEMENT"), and the
Operating Partnership Agreements; and

          WHEREAS, the GP LP desires to consent, pursuant to Section 10.2 of the
Partnership Agreement, to the admission of Sable Holdings, Raymond, Strome
Hedgecap, Strome, Kafu and E-Holdings as Substituted Limited Partners (as
defined in the Partnership Agreement) in the Partnership.

          NOW, THEREFORE, in consideration of the foregoing and the mutual
promises, representations, warranties, covenants and agreements contained
herein, the parties hereto, intending to be legally bound hereby, agree as
follows:

                                  ARTICLE I.
    CONTRIBUTIONS OF PARTNERSHIP INTERESTS AND INCENTIVE DISTRIBUTION RIGHTS

     1.1  Contribution by Departing GP to Successor GP LLC.  Departing GP hereby
grants, contributes, transfers and conveys to Successor GP LLC, its successors
and assigns, all right, title and interest in and to the LLC Incentive
Distribution Rights and Successor GP LLC hereby accepts the LLC Incentive
Distribution Rights as a contribution to the capital of Successor GP LLC.

     TO HAVE AND TO HOLD the LLC Incentive Distribution Rights unto Successor GP
LLC, its successors and assigns, together with all and singular the rights and
appurtenances thereto in anywise belonging, subject, however, to the terms and
conditions stated in this Agreement, forever.

     1.2  Contribution by Successor GP LLC to GP LP.  Successor GP LLC hereby
grants, contributes, transfers and conveys to GP LP, its successors and assigns,
all right, title and interest in and to the LLC Incentive Distribution Rights
and GP LP hereby accepts the LLC Incentive Distribution Rights as a contribution
to the capital of GP LP.

     TO HAVE AND TO HOLD the LLC Incentive Distribution Rights unto GP LP, its
successors and assigns, together with all and singular the rights and
appurtenances thereto in anywise belonging, subject, however, to the terms and
conditions stated in this Agreement, forever.

     1.3  Contribution by Departing GP to GP LP.  Departing GP hereby grants,
contributes, transfers and conveys to GP LP, its successors and assigns, all
right, title and interest in and to the LP Incentive Distribution Rights, the GP
Interest and the Operating Partnerships GP Interests and

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GP LP hereby accepts the LP Incentive Distribution Rights, the GP Interest and
the Operating Partnerships GP Interests as a contribution to the capital of GP
LP.

     TO HAVE AND TO HOLD the LP Incentive Distribution Rights, the GP Interest
and the Operating Partnerships GP Interests unto GP LP, its successors and
assigns, together with all and singular the rights and appurtenances thereto in
anywise belonging, subject, however, to the terms and conditions stated in this
Agreement, forever.

     The Partnership hereby acknowledges receipt of the opinion of counsel
required in Section 4.6(c) of the Partnership Agreement.

     1.4  Further Assurances.  From time to time after the date hereof, and
without any further consideration, Departing GP shall execute, acknowledge and
deliver all such additional assignments, stock powers, instruments, notices,
releases, acquittances and other documents, and will do all such other acts and
things, all in accordance with applicable law, as may be reasonably necessary or
appropriate more fully and effectively to assure GP LP and Successor GP LLC,
their respective successors and assigns, all of the properties, rights, titles,
interests, estates, remedies, powers and privileges by this Agreement granted to
GP LP and Successor GP LLC with respect to the LLC Incentive Distribution
Rights, the LP Incentive Distribution Rights, the GP Interest and the Operating
Partnerships GP Interests or which are intended so to be and to more fully and
effectively carry out the purposes and intent of this Agreement.

                                  ARTICLE II.
SUCCESSION OF GENERAL PARTNER OF THE PARTNERSHIP AND THE OPERATING PARTNERSHIPS

     2.1  Withdrawal of Departing GP as General Partner of Operating
Partnerships. Effective immediately prior to the contribution of the GP Interest
and the Operating Partnerships GP Interests pursuant to Section 1.3 and,
pursuant to Section 11.1(a)(ii) of each of the Partnership Agreement and the
Operating Partnership Agreements, Departing GP hereby withdraws as general
partner of the Partnership and the Operating Partnerships and proposes GP LP to
act and serve as sole general partner of the Partnership and the Operating
Partnerships.

     2.2  GP LP as Successor General Partner of the Partnership and the
Operating Partnerships. Effective immediately prior to the transfer to GP LP of
the GP Interest and the Operating Partnerships GP Interests pursuant to Section
1.3, GP LP accepts and agrees to duly and timely pay, perform and discharge the
rights, duties and obligations of the general partner of the Partnership and the
Operating Partnerships and all of the terms and conditions of the Partnership
Agreement and the Operating Partnership Agreements in accordance with Section
10.3 of the Partnership Agreement and Section 10.4 of the Operating Partnership
Agreements, and GP LP agrees to serve as general partner of the Partnership and
the Operating Partnerships and to be bound by the Partnership Agreement and the
Operating Partnership Agreements, as each is amended by this Agreement or as may
be further amended by the terms of the Partnership Agreement and the Operating
Partnership Agreements, as applicable, and GP LP is hereby admitted as the
successor general partner of the Partnership and the Operating Partnerships.

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                                 ARTICLE III.
           ASSUMPTION OF AND INDEMNIFICATION FOR CERTAIN LIABILITIES

     3.1  Assumption of Certain Liabilities and Obligations of Departing GP by
GP LP. In connection with the transfer of the GP Interest and the Operating
Partnerships GP Interests and the succession by GP LP as general partner of the
Partnership and the Operating Partnerships, GP LP hereby assumes and agrees to
duly and timely pay, perform and discharge all liabilities and obligations of
the Partnership and each Operating Partnership to the full extent (and only to
the extent) that Departing GP, as general partner, has been or would have been
in the future, were it not for the execution and delivery of this Agreement,
obligated to pay, perform and discharge such liabilities and obligations;
provided, however, that such assumption by GP LP is subject to the
indemnification provided in Section 3.2.

     3.2  Indemnification of GP LP and Successor GP LLC. Upon the transfer of
the GP Interest and the Operating Partnerships GP Interests to GP LP pursuant to
Section 1.3 hereof, Departing GP hereby indemnifies, defends and holds harmless
GP LP and Successor GP LLC from and against any and all claims, demands, costs,
liabilities and expenses (including court costs and reasonable attorneys' fees)
arising from or relating to any liability of GP LP or Successor GP LLC, whether
as general partner of the Partnership or an Operating Partnership or pursuant to
the assumption by GP LP and Successor GP LLC of liabilities and obligations of
the Partnership or an Operating Partnership pursuant to Section 3.1, for
liabilities of the Partnership and each Operating Partnership existing at the
time of the assignment of the GP Interest and the Operating Partnerships GP
Interests to GP LP pursuant to Section 1.3, but only to the extent that
Departing GP's share of such liabilities immediately prior to any assignment
under Section 1.3 exceeds Departing GP's federal income tax basis in its
aggregate partnership interest in the Operating Partnerships. For purposes of
this provision, liabilities shall mean only those shown on the balance sheet of
the Partnership and the Operating Partnerships as of the date of this Agreement.

                                  ARTICLE IV.
                      AMENDMENTS TO PARTNERSHIP AGREEMENT

     4.1  Amendments to the Partnership Agreement. In order to further the
purposes of this Agreement and to evidence the increased interest of the general
partner in the Partnership issued in exchange for the contributions to the
Partnership made pursuant to Section 2.1 hereof, Departing GP, as general
partner of the Partnership, having determined that the following amendments
would not materially adversely affect the limited partners of the Partnership or
have a material adverse effect on the holders of any class of the Partnership's
outstanding units, hereby exercises its rights and powers to amend the
Partnership Agreement without the approval of any limited partner or assignee
pursuant to Section 13.1(d)(i) of the Partnership Agreement and hereby approves
and adopts the following amendments to the Partnership Agreement in accordance
with Article XIII thereof:

          (a)  Section 1.1 is hereby amended by amending the definition of the
following term to read in its entirety as follows:

          "Conflicts Committee" means a committee of the Board of Directors of
     the general partner of the General Partner (or the applicable governing
     body of any successor to the General Partner) composed entirely of two or
     more directors who are neither security

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     holders, officers nor employees of the General Partner nor officers,
     directors or employees of any Affiliate of the General Partner.

          (b)  References in the Partnership Agreement to the Board of Directors
and officers of the General Partner are hereby amended to refer to the Board of
Directors (or the comparable governing body of any successor to the General
Partner) and officers (or the comparable governing officials of any successor to
the General Partner) of the general partner of the General Partner.

          (c)  Section 4.4(c) is hereby amended to read in its entirety as
follows:

               (c) Nothing contained in this Agreement shall be construed to
               prevent a disposition by any stockholder, member, partner or
               owner of the General Partner of any or all of the issued and
               outstanding stock, membership interests or partnership interests
               or other ownership interests of the General Partner.

       4.2  Restatement of Partnership Agreements.  Each of the partners of the
Partnership and the Operating Partnerships that is a party hereto agrees to
execute and deliver, within a reasonable period of time following the Closing
Date, a restated and amended version of each of the Partnership Agreement and
the Operating Partnership Agreements to which it is a party incorporating the
amendments to such agreement adopted by this Agreement together with such other
amendments intended to clarify the agreement as the general partner of such
limited partnership determines as are appropriate and not having a material
adverse effect on the limited partners of the partnership, and in the case of
the Partnership, the holders of outstanding common units therein.

                                  ARTICLE V.
              CONSENT TO ADMISSION OF SUBSTITUTED LIMITED PARTNERS

     GP LP hereby consents, pursuant to Section 10.2 of the Partnership
Agreement, to the admission of Sable Holdings, Raymond, Strome Hedgecap, Strome,
Kafu and E-Holdings as Substituted Limited Partners (as defined in the
Partnership Agreement) in the Partnership.  GP LP represents that as of the date
hereof such admissions have been reflected on the books and records of the
Partnership.

                                  ARTICLE VI.
                                 MISCELLANEOUS

     6.1  Other Assurances. From time to time after the date hereof, and without
any further consideration, each of the parties to this Agreement shall execute,
acknowledge and deliver all such additional instruments, notices and other
documents, and will do all such other acts and things, all in accordance with
applicable law, as may be necessary or appropriate to more fully and effectively
carry out the purposes and intent of this Agreement.

     6.2  Consents; Restriction on Assignment. If there are prohibitions against
or conditions to the contribution and assignment of one or more portions of the
assets contributed pursuant to

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Article II without the prior written consent of third parties, including,
without limitation, governmental agencies (other than consents of a ministerial
nature that are normally granted in the ordinary course of business), which if
not satisfied would result in a breach of such prohibitions or conditions or
would give an outside party the right to terminate the GP LP's rights with
respect to such portion of the contributed assets (herein called a
"Restriction"), then any provision contained in this Agreement to the contrary
notwithstanding, the transfer of title to or interest in each such portion of
the contributed assets (herein called the "Restriction-Asset") pursuant to this
Agreement shall not become effective unless and until such Restriction is
satisfied, waived or no longer applies. When and if such a Restriction is so
satisfied, waived or no longer applies, to the extent permitted by applicable
law and any applicable contractual provisions, the assignment of the
Restriction-Asset subject thereto shall become effective automatically, without
further action on the part of GP LP or Departing GP and Departing GP agrees to
use its reasonable best efforts to obtain satisfaction of any Restriction on a
timely basis. In the event that any Restriction-Asset exists, Departing GP
agrees to hold such Restriction-Asset in trust for the exclusive benefit of the
assignee or GP LP, as the case may be, and to otherwise use its reasonable best
efforts to provide the assignee with the benefits thereof, and Departing GP will
enter into other agreements, or take such other action as it may deem reasonably
necessary, in order to help ensure that such assignee is entitled to the
benefits of the contributed assets and concomitant rights in all material
respects.

     6.3  Costs. The Partnership shall pay all sales, use and similar taxes
arising out of the contributions, assignments and deliveries to be made
hereunder, and shall pay all documentary, filing, recording, transfer, deed, and
conveyance taxes and fees required in connection therewith. In addition, the
Partnership shall be responsible for all costs, liabilities and expenses
(including court costs and reasonable attorneys' fees) incurred in connection
with the satisfaction or waiver of any Restriction pursuant to Section 6.2.

     6.4  Headings; References; Interpretation. All Article and Section headings
in this Agreement are for convenience only and shall not be deemed to control or
affect the meaning or construction of any of the provisions hereof. The words
"hereof," "herein" and "hereunder" and words of similar import, when used in
this Agreement, shall refer to this Agreement as a whole, and not to any
particular provision of this Agreement. All references herein to Articles and
Sections shall, unless the context requires a different construction, be deemed
to be references to the Articles, and Sections of this Agreement, respectively.
All personal pronouns used in this Agreement, whether used in the masculine,
feminine or neuter gender, shall include all other genders, and the singular
shall include the plural and vice versa. The use herein of the word "including"
following any general statement, term or matter shall not be construed to limit
such statement, term or matter to the specific items or matters set forth
immediately following such word or to similar items or matters, whether or not
non-limiting language (such as "without limitation," "but not limited to," or
words of similar import) is used with reference thereto, but rather shall be
deemed to refer to all other items or matters that could reasonably fall within
the broadest possible scope of such general statement, term or matter.

     6.5  Successors and Assigns. The Agreement shall be binding upon and inure
to the benefit of the parties signatory hereto and their respective successors
and assigns.

     6.6  No Third Party Rights. The provisions of this Agreement are intended
to bind the parties signatory hereto as to each other and are not intended to
and do not create rights in any other

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person or confer upon any other person any benefits, rights or remedies and no
person is or is intended to be a third party beneficiary of any of the
provisions of this Agreement.

     6.7  Counterparts.  This Agreement may be executed in any number of
counterparts, all of which together shall constitute one agreement binding on
the parties hereto.

     6.8  Governing Law.  This Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware applicable to contracts made
and to be performed wholly within such state without giving effect to conflict
of law principles thereof, except to the extent that it is mandatory that the
law of some other jurisdiction, wherein the contributed assets are deemed
located, shall apply.

     6.9  Severability. If any of the provisions of this Agreement are held by
any court of competent jurisdiction to contravene, or to be invalid under, the
laws of any political body having jurisdiction over the subject matter hereof,
such contravention or invalidity shall not invalidate the entire Agreement.
Instead, this Agreement shall be construed as if it did not contain the
particular provision or provisions held to be invalid, and an equitable
adjustment shall be made and necessary provision added so as to give effect to
the intention of the parties as expressed in this Agreement at the time of
execution of this Agreement.

     6.10  Assignment.  To the extent required by applicable law, this Agreement
shall also be an "assignment" of the assets transferred and contributed as set
forth in Article II hereof.

     6.11  Amendment or Modification. This Agreement may be amended or modified
from time to time only by the written agreement of all the parties hereto.

     6.12  Integration. This Agreement supersedes all previous understandings or
agreements between the parties, whether oral or written, with respect to its
subject matter. This document is an integrated agreement which contains the
entire understanding of the parties. No understanding, representation, promise
or agreement, whether oral or written, is intended to be or shall be included in
or form part of this Agreement unless it is contained in a written amendment
hereto executed by the parties hereto after the date of this Agreement.

                            [signature page follows]

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          IN WITNESS WHEREOF, this Agreement has been duly executed by the
parties hereto as of the date first above written.


                              PLAINS ALL AMERICAN INC., a Delaware corporation


                              By: /s/ Tim Moore
                                 --------------------------------
                              Name:  Tim Moore
                              Title: Vice President



                              PLAINS AAP, L.P., a Delaware limited partnership

                              By:  Plains All American GP LLC


                              By: /s/ Tim Moore
                                 --------------------------------
                              Name:  Tim Moore
                              Title: Vice President

                              PLAINS ALL AMERICAN GP LLC, a Delaware limited
                              liability company


                              By: /s/ Tim Moore
                                 --------------------------------
                              Name:  Tim Moore
                              Title: Vice President

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