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                                                                 EXHIBIT 10.BB.2



                           THIRD AMENDED AND RESTATED
                       LIMITED LIABILITY COMPANY AGREEMENT
                                       OF
                           MESQUITE INVESTORS, L.L.C.





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                           MESQUITE INVESTORS, L.L.C.

                           THIRD AMENDED AND RESTATED

                       LIMITED LIABILITY COMPANY AGREEMENT


         THIRD AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT of
Mesquite Investors, L.L.C., a Delaware limited liability company ("MESQUITE")
dated as of March 27, 2000, by Chaparral Investors, L.L.C., a Delaware limited
liability company ("CHAPARRAL" or the "MEMBER") and Mesquite.


                             PRELIMINARY STATEMENTS

         Mesquite was formed as a limited liability company under and pursuant
to the provisions of the LLC Act, pursuant to the filing of the Certificate (as
hereinafter defined) on July 28, 1999, and the execution of the Limited
Liability Company Agreement dated as of July 28, 1999 (the "ORIGINAL
AGREEMENT"), as amended and restated by (i) that certain First Amended and
Restated Agreement of Limited Liability Company dated as of August 12, 1999,
(ii) the First Amendment dated as of August 19, 1999 and (iii) that certain
Second Amended and Restated Agreement of Limited Liability Company dated as of
December 28, 1999 (collectively, the "EXISTING AGREEMENT").

         Prior to the Closing Date, Chaparral has transferred to Mesquite
certain Qualified Energy Assets and the Contingent Debt Instrument. On the
Closing Date, Chaparral will make a cash contribution to Mesquite in the amount
of $796,013,202.43, which will be used by Mesquite to (i) repay $664,659,193.26
in outstanding indebtedness under the Mesquite Credit Agreement and (ii) make El
Paso Loans in the amount of $131,354,009.17.

         SECTION 1.  DEFINITIONS.

         (a) As used in this Mesquite LLC Agreement, capitalized terms defined
in the preamble and other Sections of this Mesquite LLC Agreement shall have the
meanings set forth therein, and capitalized terms that are defined in Section
1.01 of Annex A to the Chaparral LLC Agreement shall have the meanings therefor
set forth in such Annex A.

         (b) The following terms shall have the following meanings when used
herein:

         "CERTIFICATE" means the certificate of formation filed with the
Secretary of State of the State of Delaware on July 28, 1999, to form Mesquite
pursuant to the LLC Act, as originally executed by Kelly Jameson (as an
authorized person within the meaning of the LLC Act) and as amended, modified,
supplemented or restated from time to time, as the context requires.

         "CHAPARRAL LLC AGREEMENT" means the Fourth Amended and Restated Limited
Liability Company Agreement of Chaparral, dated as of March 27, 2000, as
amended, supplemented, amended and restated or otherwise modified from time to
time.

         "DISSOLUTION EVENTS" is defined in Section 17.

         "EXISTING AGREEMENT" is defined in the preamble.

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         "MEMBERSHIP INTEREST" or "INTEREST" means the entire ownership interest
in Mesquite and the right to receive regular and liquidating distributions to
the extent provided in this Mesquite LLC Agreement, the right to participate in
the management of the business and affairs of Mesquite as set forth herein,
including the right to vote on, consent to, or otherwise participate in any
decision or action of or by Mesquite granted pursuant to this Mesquite LLC
Agreement and the LLC Act. Such Interest shall be evidenced by the certificate
issued pursuant to Section 9 hereof.

         "MESQUITE CONFIDENTIAL INFORMATION" means available financial
(including, but not limited to, budgets, forecasts, pro forma or any associated
financial or other spreadsheet models) and other information concerning the
business and/or operations and/or financial and/or other condition or prospects
of Mesquite and its subsidiaries and other affiliates, including, but not
limited to, each Project Company, and any proposed Project Company, and its or
their respective subsidiaries and other affiliates ("MESQUITE SOURCES") that is
subject to confidentiality agreements or other contracts or terms otherwise
restricting disclosure of information applicable to the business and/or
operations and/or financial and/or other condition or prospects of Mesquite
Sources.

         "ORIGINAL AGREEMENT" is defined in the preamble.

         SECTION 2. RULES OF CONSTRUCTION. This Mesquite LLC Agreement and the
definitions referred to in Section 1(a) shall be governed by, and construed in
accordance with, the rules of construction set forth in Section 1.02 of Annex A
to the Chaparral LLC Agreement.

         SECTION 3. CONTINUATION. Chaparral hereby agrees to continue Mesquite
as a limited liability company under and pursuant to the provisions of the LLC
Act and upon the terms and conditions set forth in this Mesquite LLC Agreement.
Chaparral agrees that the Existing Agreement is hereby amended and restated in
its entirety as set forth in, and is hereby superseded in its entirety by, this
Mesquite LLC Agreement.

         SECTION 4. NAME. The name of Mesquite shall continue to be "Mesquite
Investors, L.L.C." and all business of Mesquite shall be conducted in such name.
Chaparral may change the name of Mesquite at any time.

         SECTION 5. PURPOSE; POWERS. The purposes of Mesquite are limited to:
(a) acquiring, owning, holding, forming, selling, leasing, transferring,
exchanging, operating and managing, making investments in, participating in,
disposing of, and exercising rights with respect to, Mesquite Permitted Assets;
(b) engaging directly in, or entering into any agreement or other Contractual
Obligation, or forming any Person, to engage directly or indirectly in, any
business activity that is directly or indirectly related to the activities
described in clause (a) above; (c) engaging in such additional business
activities as are permitted under this Mesquite LLC Agreement or otherwise as
Chaparral, in accordance with the Chaparral LLC Agreement, may direct in
writing; (d) entering into any agreement or other Contractual Obligation, or
forming any Person, to engage directly or indirectly in any business activity
that is directly or indirectly related to the activities described in clause (c)
above; (e) entering into and performing its obligations under the Transaction
Documents to which it is a party; (f) incurring Mesquite Permitted Financial
Obligations; and (g) engaging in activities related or incidental to the
foregoing. Mesquite shall have the power to do any and all acts necessary,
appropriate, proper, advisable, incidental or convenient to or in furtherance of
the purposes of Mesquite set forth in this Section 5.

         SECTION 6. PRINCIPAL PLACE OF BUSINESS; REGISTERED OFFICE. The
principal place of business of Mesquite shall continue to be located at c/o
Wilmington Trust Company, Rodney Square North, 1100 North Market Street, New
Castle County, Wilmington, Delaware 19890-0001, Attention: Corporate Trust
Administration, and Mesquite's business shall be conducted from such place or
places as Chaparral


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may designate from time to time. The registered office of Mesquite in the State
of Delaware shall be located at c/o Wilmington Trust Company, Rodney Square
North, 1100 North Market Street, New Castle County, Wilmington, Delaware
19890-0001, Attention: Corporate Trust Administration. Chaparral may from time
to time change the registered office of Mesquite by an amendment to the
Certificate of Mesquite.

         SECTION 7. REGISTERED AGENT. The name and address of the registered
agent of Mesquite for service of process on Mesquite in the State of Delaware
shall be c/o Wilmington Trust Company, Rodney Square North, 1100 North Market
Street, New Castle County, Wilmington, Delaware 19890-0001, Attention: Corporate
Trust Administration. Chaparral may from time to time change the registered
agent by an amendment to the Certificate of Mesquite.

         SECTION 8. TERM. The term of Mesquite commenced on the date the
Certificate was filed in the Office of the Secretary of State of the State of
Delaware in accordance with the LLC Act, and shall continue until the winding up
and liquidation of Mesquite and the completion of its business following a
Dissolution Event as provided in Section 17 hereof.

         SECTION 9. MEMBER. At no time may Mesquite have more than one member.
Chaparral shall be the sole member of Mesquite. A certificate in the form
attached as Exhibit A hereto shall be issued to Chaparral on the Closing Date to
evidence its interest as the sole member of Mesquite, and Chaparral, as sole
member of Mesquite, is hereby authorized and directed to execute such
certificate. Each of the parties hereto hereby acknowledges and agrees that
Chaparral's interest in Mesquite shall constitute a "security" governed by
Article 8 of the Uniform Commercial Code as in effect in any applicable
jurisdiction.

         SECTION 10. CAPITAL CONTRIBUTIONS. Chaparral may contribute cash or
other property to Mesquite as it shall decide, from time to time, provided that
any such contribution is permissible under Section 5 hereof.

         SECTION 11. TAX CHARACTERIZATION AND RETURNS. For so long as Chaparral
is the sole member of Mesquite, it is the intention of Chaparral that Mesquite
be disregarded for federal and all relevant state tax purposes and that the
activities of Mesquite be deemed to be the activities of Chaparral for such
purposes. Chaparral is hereby authorized to file any necessary elections with
any tax authorities.

         SECTION 12. MANAGEMENT. The management of Mesquite shall be vested
solely in Chaparral, which shall have all powers to control and manage the
business and affairs of Mesquite and may exercise all powers of Mesquite.
Chaparral and Mesquite are hereby authorized and directed to enter into the
Management Agreement, pursuant to which Chaparral will delegate certain of its
managerial responsibilities hereunder, as more specifically set forth in the
Management Agreement.

         SECTION 13. RESTRICTIONS ON AUTHORITY OF THE MEMBER AND ACTIVITIES OF
MESQUITE.

         (a) Indebtedness, Etc. Chaparral shall not cause or permit Mesquite to,
nor shall Mesquite, incur, assume or obligate itself by contract for any
Permitted Financial Obligations owing by Mesquite other than Mesquite Permitted
Financial Obligations; provided, further, that Chaparral shall not cause or
permit Mesquite to, nor shall Mesquite, enter into any Mesquite Permitted
Financial Obligations that impose greater restrictions (on a pro rata basis) on
(i) Mesquite's ability to Distribute to Chaparral funds sufficient to pay when
due (x) the Class A Member's Cumulative Priority Return or (y) any Distribution
required to be made pursuant to Section 5.1(c) of the Chaparral LLC Agreement
than (ii) are applicable to Mesquite's ability to pay the Management Fee.


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         (b) Mergers. Chaparral shall not cause or permit Mesquite to, nor shall
Mesquite, legally merge or consolidate with or into any Person.

         (c) Business Activities. Chaparral shall not cause or permit Mesquite
to, nor shall Mesquite, engage in any activities other than those described in
Section 5.

         (d) Voluntary Bankruptcy. Chaparral shall not cause or permit Mesquite,
nor shall Mesquite, commence any Voluntary Bankruptcy of Mesquite.

         SECTION 14. DISTRIBUTIONS. Chaparral may cause Mesquite to distribute
any cash held by it or any other Mesquite Property that is neither reasonably
necessary for the operation of Mesquite nor in violation of Sections 18-607 or
18-804 of the LLC Act to Chaparral at any time.

         SECTION 15. TRANSFER. Chaparral shall not Dispose of all or any part of
its Membership Interest except as permitted under the Chaparral LLC Agreement.

         SECTION 16. DISTRIBUTIONS UPON DISSOLUTION. Upon the occurrence of a
Dissolution Event, Chaparral shall be entitled to receive, after paying or
making reasonable provision for all of Mesquite's creditors to the extent
required by Section 18-804 of the LLC Act, the remaining Mesquite Property.

         SECTION 17. DISSOLUTION. Mesquite shall dissolve, and commence winding
up and liquidating upon the first to occur of any of the following
(collectively, "DISSOLUTION EVENTS"):

                  (a) Chaparral shall have given its consent for Mesquite to
         dissolve;

                  (b) a judicial dissolution of Mesquite pursuant to Section
         18-802 of the LLC Act; and

                  (c) such time as there are no members of Mesquite (provided,
         that if within ninety days following any event terminating the
         continued membership of Chaparral, the Personal Representative (as
         defined in the LLC Act) of Chaparral agrees in writing to continue
         Mesquite and to admit itself or some other Person as a member of
         Mesquite effective as of the date of the occurrence of the event that
         terminated the continued membership of Chaparral, then Mesquite shall
         not be dissolved and its affairs shall not be wound up).

         Anything in this Mesquite LLC Agreement to the contrary
notwithstanding, for so long as any Obligation of Mesquite is outstanding: (i)
the "Bankruptcy" (as defined in the LLC Act) of Chaparral shall not cause
Chaparral to cease to be a member of Mesquite and upon the occurrence of such
Bankruptcy, the business of Mesquite shall continue without dissolution; (ii)
Chaparral waives any right that it might have under Section 18-801(b) of the LLC
Act to agree in writing to dissolve Mesquite upon the Bankruptcy of Chaparral or
the occurrence of any event that causes Chaparral to cease to be a member of
Mesquite and (iii) the existence of Mesquite as a separate legal entity shall
continue until the cancellation of its Certificate as provided in the LLC Act.

         SECTION 18. WITHDRAWAL. Chaparral shall not withdraw from Mesquite in
respect of its Membership Interest.

         SECTION 19. TRANSACTIONS WITH AFFILIATES. All transactions between any
of Limestone, El Paso, El Paso Chaparral, or El Paso Chaparral Holding Company
(or any of their respective Affiliates), on the one hand, and Chaparral on
behalf of Mesquite, on the other hand, shall comply with the provisions of
Section 6.5(a)(ii) of the Chaparral LLC Agreement.


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         SECTION 20. CONFIDENTIALITY. Chaparral hereby agrees that it is and
will be bound by the terms and conditions of any Applicable Law or Contractual
Obligation respecting confidentiality binding upon Mesquite, any Subsidiary of
Mesquite or any Mesquite Minority Owned QEC with respect to Mesquite
Confidential Information.

         SECTION 21. SEPARATENESS COVENANTS. Mesquite covenants that:

         (a) It shall: (i) maintain and prepare separate financial reports and
financial statements, showing its assets and liabilities separate and apart from
those of any other Person, and will not have its assets listed on the financial
statement of any other Person; provided, however, that its assets may be
included on a consolidated financial statement of its parent if: (A) such
consolidated financial statement shall contain a footnote to the effect that
Mesquite's assets are owned by Mesquite, and (B) such assets shall be listed on
Mesquite's own balance sheet; (ii) maintain its books, records and bank accounts
separate from those of its Affiliates, any constituent party and any other
Person; and (iii) not permit any Affiliate or constituent party independent
access to its bank accounts (other than access by Chaparral in its capacity as
sole member of Mesquite).

         (b) It shall not commingle or pool any of the funds and other assets of
Mesquite with those of any Affiliate or constituent party or any other Person,
and it shall hold all of its assets in its own name.

         (c) It has done, or caused to be done, and shall do, all things
necessary to observe all Delaware limited liability company formalities and
other organizational formalities, and preserve its existence.

         (d) It does not, and shall not, guarantee, become obligated for, or
hold itself or its credit out to be responsible for or available to satisfy, the
debts or obligations of any other Person or the decisions or actions respecting
the daily business or affairs of any other Person (except Mesquite Permitted
Financial Obligations and except as otherwise provided for in or permitted under
the Transaction Documents).

         (e) It shall not acquire Equity Interests of any Affiliate or of
Chaparral (other than Mesquite Permitted Assets and except as otherwise provided
for in or permitted under this Mesquite LLC Agreement or the other Transaction
Documents). It shall not buy or hold any evidence of indebtedness for borrowed
money issued by, or make any loan or advance to, any other Person (other than
any such evidence of indebtedness for borrowed money, loan or advance
constituting Mesquite Permitted Assets, and except as otherwise provided for in
or permitted under this Mesquite LLC Agreement or the other Transaction
Documents).

         (f) Mesquite shall not be consensually merged or legally consolidated
with any other Person (other than certain Affiliates for financial reporting and
federal tax purposes).

         (g) Each bank account of Mesquite shall be separate from the bank
accounts of any other Person.

         (h) Mesquite shall not permit or suffer to exist any Liens on its
assets other than (i) Permitted Liens and (ii) Liens securing any Mesquite
Permitted Financial Obligations.

         SECTION 22. LIMITED LIABILITY. Chaparral shall have no liability for
Mesquite Permitted Financial Obligations or any other Obligations of Mesquite
except to the extent expressly required by the LLC Act.


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         SECTION 23. AMENDMENT. This Mesquite LLC Agreement may be amended only
in a writing signed by Chaparral and subject to the terms and conditions of the
Chaparral LLC Agreement.

         SECTION 24. ENFORCEABILITY OF AGREEMENT. Notwithstanding any other
provision of this Mesquite LLC Agreement to the contrary, Chaparral hereby
agrees that this Mesquite LLC Agreement constitutes a legal, valid and binding
agreement of Chaparral.

         SECTION 25. GOVERNING LAW. THE LAWS OF THE STATE OF DELAWARE (WITHOUT
REGARD TO CONFLICT OF LAW PRINCIPLES) SHALL GOVERN THE VALIDITY OF THIS MESQUITE
LLC AGREEMENT, THE CONSTRUCTION OF ITS TERMS, AND THE INTERPRETATION OF THE
RIGHTS AND DUTIES OF THE MEMBER OR MEMBERS OF MESQUITE.

         SECTION 26. SEVERABILITY. Any provision of this Mesquite LLC Agreement
that is prohibited by or unenforceable in any relevant jurisdiction shall, as to
such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions thereof, and any
such prohibition or unenforceability in any jurisdiction shall not invalidate or
render unenforceable such provision in any other jurisdiction.

         SECTION 27. CONSENT TO JURISDICTION PROVISION. Chaparral hereby (i)
irrevocably submits to the non-exclusive jurisdiction of any Delaware State
court or Federal court sitting in Wilmington, Delaware in any action arising out
of this Mesquite LLC Agreement, (ii) agrees that all claims in such action may
be decided in such court, (iii) waives, to the fullest extent it may effectively
do so, the defense of an inconvenient forum, and (iv) consents to the service of
process by mail. A final judgment in any such action shall be conclusive and may
be enforced in other jurisdictions. Nothing herein shall affect the right of any
party to serve legal process in any manner permitted by law or affect its right
to bring any action in any other court.


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         IN WITNESS WHEREOF, the undersigned have caused this Third Amended and
Restated Limited Liability Company Agreement to be executed as of the day and
year first above written.

                                    MESQUITE INVESTORS, L.L.C.

                                    By:  Chaparral Investors, L.L.C.,
                                           its sole member

                                         By: El Paso Chaparral Investor, L.L.C.,
                                              its managing member

                                             By: El Paso Chaparral Holding
                                                  Company, its sole member



                                             By:  /s/ John L. Harrison
                                                  -----------------------------
                                                  Name:  John L. Harrison
                                                  Title: Vice President


                             Mesquite LLC Agreement
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                                    CHAPARRAL INVESTORS, L.L.C.

                                    By: El Paso Chaparral Investor, L.L.C.,
                                        its managing member

                                        By: El Paso Chaparral Holding Company,
                                            its sole member



                                            By:      /s/ John L. Harrison
                                                --------------------------------
                                                Name:  John L. Harrison
                                                Title: Vice President


                             Mesquite LLC Agreement