PARTNERSHIP AGREEMENT

      THIS PARTNERSHIP AGREEMENT is made and entered into as of the 30th day
of August, 1985, by and between VULCAN POWER COMPANY, 631 South Witmer Street,
P. O. Box 17760, Los Angeles, California 90017, a Nevada corporation
("Vulcan"), and BN GEOTHERMAL, INC., P.0. Box 1492, El Paso, Texas 79978, a
Delaware corporation ("BNG").

      In consideration of the mutual convenants hereinafter set forth, the
parties hereto agree as follows:

                                   ARTICLE I
                           FORMATION OF PARTNERSHIP
1.1    Formation.
       Pursuant to the Uniform Partnership Act of the State of Nevada, the
       parties hereto (the "Partners"), hereby associate themselves together
       to form a partnership (the "Partnership"). The parties shall
       immediately take such steps as are necessary to comply with all
       requirements for the formation and continuation of a partnership under
       said Act and to comply with the requirements of the assumed name or
       similar statutes in effect in the State of Nevada.

1.2    Partnership Name.
       The Partnership shall operate under the name of, and shall be known as,
       VULCAN/BN GEOTHERMAL POWER COMPANY. The parties shall take such steps
       as are necessary to terminate any prior use of this name and to secure
       for the





    




       Partnership the rights to this name free of any earlier purposes and
       any liabilities possibly associated therewith.

1.3    Purposes of Partnership.
       The fundamental purpose of the Partnership is the acquisition,
       construction, ownership and operation of a single geothermal-electric
       generating facility now under construction near Calipatria, California
       (the "Vulcan Facility"), and any activities incidental to such
       fundamental purpose, as well as to carry on all such other activities
       related thereto as are not forbidden by the laws of the State of
       Nevada.

1.4    Place of Business.
       The principal place of business and office of the Partnership shall be
       located at 7001 Gentry Road, Calipatria, California 92233, and may
       subsequently be moved to such other location as from time to time may
       be determined by the Management Committee (as defined hereinafter) of
       the Partnership and reflected in a duly filed amendment to the
       Partnership certificate. The Partnership may maintain such other
       offices at any other location or locations as the Management Committee
       may from time to time deem advisable.

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                                  ARTICLE II
                          CAPITAL AND DEBT FINANCING

2.1   Capital of the Partnership.

      (a)  Initial Capital Contributions.
           The initial capital of the Partnership shall consist of the
           following described assets (the "Partnership Assets"), an undivided
           one-half (1/2) interest of which is to be contributed by each
           Partner:

           (1)  The physical plant of the Vulcan Facility described in
                Exhibit A attached hereto and incorporated herein by
                reference; and

           (2)  The eighteen (18) completed wells (including intangible
                drilling costs) associated with the Vulcan Facility described
                in Exhibit B attached hereto and incorporated herein by
                reference, along with rights of ingress and egress to said
                wells, subject to Vulcan's right to repurchase described in
                Section 9.1 hereof.

      (b)  Payment of Initial Capital Contributions. Immediately following the
           execution of this Partnership Agreement, the Partners shall each
           contribute to the Partnership an undivided one-half (1/2) interest
           in the Partnership Assets and be credited the amount of capital
           shown on Exhibit C, attached hereto and made a part hereof.



                                  3




    





           (c) Additional Capital Contributions and Withdrawals. Equal
           additional contributions to capital, whether needed to complete the
           Vulcan Facility, to cover costs of operation, or to otherwise
           accomplish the purposes of the Partnership, shall be made by the
           Partners when, and in the manner and amount, requested by Vulcan
           and approved by unanimous consent of the Management Committee.
           Failure to make such additional capital contributions shall cause
           an automatic adjustment in the distribution of profits and losses
           in accordance with Section 3.2 below. Withdrawals of capital shall
           be made only by unanimous decision of the Management Committee.
           Both additional capital contributions and withdrawals shall be made
           upon the following conditions:

           (1)  The preparation of a revised schedule of capital contributions
                (similar in form to Exhibit C) showing the then aggregate
                capital contributions of both Partners, which revised schedule
                shall thereafter be attached hereto; and

           (2)  The filing of a properly revised partnership certificate in
                the office of the clerk of the county where the principal
                place of business of the Partnership is then located, if such
                a revised partnership certificate is then required by law.



                                       4



    





2.2   Partner's Capital.
      The Partner's capital for each Partner shall reflect its interest in the
      net book value of the assets and liabilities of the Partnership. The
      initial amount of each Partner's capital shall be the initial capital
      contribution made by that Partner. Each Partner's capital shall
      thereafter be increased by any additional capital contributions made by
      such Partner and decreased by any withdrawals of capital made by such
      Partner. Capital contributions or withdrawals made other than in cash
      shall be reflected at the value of the property involved as agreed upon
      by the Partners.

2.3   Interest in the Partnership Defined.
      A Partner's "interest in the Partnership", as that term is used
      throughout this Partnership Agreement, refers to its entire interest in
      and with respect to the Partnership including its interest in the
      capital and profits of the Partnership (unreduced by any amounts owed by
      such Partner to the Partnership, but such interest shall constitute
      security for the repayment of such debts). A Partner's interest in the
      Partnership shall not include any amounts owed to that Partner by the
      Partnership or to the Partnership by that Partner on written promissory
      notes nor shall such expression include a Partner's right to participate
      as a Partner in the management of the Partnership or any of its
      property. No Partner in its individual capacity shall have any ownership
      of the property of the Partnership.


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2.4   Partnership Distributions.
      Distributions to Partners shall be made only to the extent that the
      Partners acting jointly may determine from time to time that such
      distributions are in the best interest of the Partnership; provided,
      however, that proceeds received by the Partnership as a result of the
      sale by the Partnership of its assets (or a portion thereof), whether
      pursuant to a purchase agreement granted by the Partnership to a Partner
      or otherwise, shall be first applied to retire the outstanding debts of
      the Partnership and any residual shall be immediately distributed to the
      Partners in equal proportion, unless the Partners shall agree otherwise.
      No Interest shall be paid to a Partner on its capital in the
      Partnership.

2.5   The Partnership's Anticipated Financial Needs.

      (a)  Financing of the Vulcan Facility.
           It is the specific intent of the Partners that financing for the
           acquisition and construction of the Vulcan Facility be obtained
           solely from capital contributions made by the Partners, such
           financing being presently estimated to be approximately Seventy-
           three Million Dollars ($73,000,000), U.S.

      (b)  Additional-Funds Required for the Partnership.
           It is the specific intent of the Partners to fund all other
           financial needs of the Partnership solely from operations and/or
           additional capital contributions made by the Partners. If at any
           time or times the


                                       6




    





           Partnership should require additional funds for such other needs
           which it is unable to generate through its own operations and
           which, for any reason, the Partnership does not wish to raise
           through an increase in the Partnership capital pursuant to the
           provisions of Section 2.1(c) above, the Management Committee, by
           unanimous decision, may authorize such additional funds to be
           borrowed by the Partnership, upon such terms as the Management
           Committee may agree, using one or more of the following methods:

           (1)  From third parties based on the Partnership's own credit;

           (2)  From the Partners (in equal amounts);

           (3)  From third parties, by means of corporate guarantees of the
                Partners, with the burden with respect to the amounts, form
                and terms of such loans to be borne substantially equally by
                the Partners, unless they otherwise agree.

                                  ARTICLE III
                              PROFITS AND LOSSES

3.1   Profit and Losses Defined.
      Throughout this Partnership Agreement, the term "profits and losses of
      the Partnership" shall mean the net profits or net losses of the
      Partnership, including realized capital gains and losses, as determined
      in the Partnership's books of account. The Partnership's books of
      account shall be kept


                                      7




    




      using the accrual method of accounting, applying generally accepted
      accounting principles. Commencing with the calendar year 1986, the
      Partnership's fiscal year shall be the calendar year.

3.2   Division Between Partners.
      The profits and losses of the Partnership shall be credited or charged
      to the Partners in equal proportions. However, if a Partner fails to
      make any additional capital contribution required by Section 2.1(c)
      above, it is understood and agreed by the parties hereto that the
      division of profits and losses specified herein shall be automatically
      adjusted so as to allocate to each Partner a fraction of the profits and
      losses, the numerator of which shall be (a) one-half of the total of
      both Partners' capital accounts before any additional capital
      contributions plus (b) any additional capital contributions made by the
      individual Partner; and, the denominator of which shall be the total of
      both Partners' capital accounts after all additional capital
      contributions.

3.3   Consequences of Default in Capital Contributions.
      A partner which fails to make additional capital contributions required
      by Section 2.l(c) above shall be hereinafter referred to as a
      "defaulting Partner". While any Partner is in default:

      (a)  No distributions shall be made to such defaulting Partner and any
           interest or other earnings on amounts withheld from such defaulting
           Partner shall accrue to


                                      8




    




           the non-defaulting Partner; provided, however, that upon the
           unanimous consent of the Management Committee, any counts withheld
           from such defaulting Partner pursuant to this Section, together
           with any interest or other earnings on such withheld amounts, may
           be credited to the capital account of such defaulting partner;

      (b)  the non-defaulting Partner may, at its option, consider the sums
           advanced by it (and not matched by the defaulting Partner) to be a
           loan to the Partnership; and

      (c)  except as provided in this Section 3.3, and in Section 7.1 of this
           Partnership Agreement, such defaulting Partner shall continue to be
           a Partner subject to all of the terms and conditions of this
           Partnership Agreement.

   A defaulting Partner shall be liable to the Partnership and to the
   non-defaulting Partner for all losses, damages and expenses sustained or
   incurred by the Partnership and such non-defaulting Partner as a result of
   such default, including, without limitation, any additional tax liabilities
   and interest, and any allocation of Partnership losses resulting from such
   default.

3.4   Compensation of Partners.
      Each Partner shall receive reasonable compensation for any services
      (such as bookkeeping services or tax return preparation services)
      rendered by it to the Partnership, but


                                      9



    




      only after provision for such compensation has been made in a written
      agreement between the Partners or between the Partner rendering such
      services and the Partnership. Any such compensation shall be deducted
      from Partnership income, as in the case of any other expense, in
      determining the profit or loss allocable among the Partners under the
      provisions of Section 3.2 above.

3.5   Reimbursement for Expenses.
      Each Partner shall be entitled to be reimbursed by the Partnership, as
      an expense of the Partnership, for its actual, reasonable and necessary
      expenses authorized by the Partners and incurred in behalf of the
      Partnership, upon filing an itemized account of such expenses in the
      records of the Partnership.

                                  ARTICLE IV
                                     TAXES

4.1   Responsibilities for Income Taxes; Preparation of Partnership Returns.

      AA soon as practicable following the end of each fiscal year of the
      Partnership, the Partnership shall cause the Operator (as hereinafter
      defined) to prepare and deliver to each Partner such federal, state and
      local income tax returns and such other accounting information, tax
      information and schedules as shall be necessary for the preparation by
      each Partner of its income tax returns for such fiscal year. The
      Operator shall submit copies of all returns to each Partner not less
      than forty-five (45) days prior to the date upon


                                      10




    




      which such returns are required to be filed (including extensions of
      time obtained by the Operator) to permit review and approval of the
      returns prior to filing.

      The Operator shall file or cause to be filed, subject to Management
      Committee review and approval, such federal income tax returns as may be
      required in respect of the Partnership.

4.2   Allocation of Tax Benefits and Burdens.
      For income tax purposes, depreciation deductions shall be allocated to
      the Partners based upon the value of the capital contributions of the
      Partners stated as a percentage of total capital contributions. The
      Partners shall share the investment and energy tax credits in accordance
      with the applicable provisions of the Internal Revenue Code of 1954, as
      amended, and the Treasury Regulations promulgated thereunder.

4.3   Elections in U.S. Income Tax Returns.
      In preparing the federal U.S. Partnership income tax returns for the
      Partnership, the following elections shall be made:

      (a)  A calendar taxable year;

      (b)  The accrual method of accounting;

      (c)  The depreciation method for each asset most beneficial to the
           Partners as determined by the Partners;

      (d)  The full amount of credit under Internal Revenue Code Section 46(a)
           ; and


                                      11



    




      (e) in respect of any election not specified, the method providing
          for the most immediate deduction shall be chosen.

4.4   Termination Within the Meaning of IRC Section 708.
      No sale or exchange of any Partnership interest, or any fraction
      thereof, may be made if the interest sought to be sold or exchanged,
      when added to the total of all other interests sold or exchanged within
      the period of 12 consecutive months prior thereto, would, in the opinion
      of tax counsel for the Partnership (as selected by either Partner),
      result in the Partnership being considered to have been terminated
      within the meaning of Section 708 of the Internal Revenue Code of 1954,
      as amended, or any similar provision enacted in lieu thereof.

4.5   IRC Section 754 Election.
      The Operator or other party who is responsible for filing the
      Partnership's federal tax return shall, if the Partners so desire, make
      or attempt to revoke the election referred to in Section 754 of the
      Internal Revenue Code of 1954, as amended, or any similar provision
      enacted in lieu thereof. Each of the Partners shall, upon request,
      supply the information necessary to properly give effect to any such
      election.

4.6   State and Local Franchise and Income Tax Returns.
      The Operator, on behalf of and for the account of the Partnership and
      subject to review and approval of the Management Committee, shall file
      (or cause to have filed)


                                      12




    




      all returns and make (or cause to be made) all payments for the
      Partnership of all state and local franchise or income taxes levied
      directly on the Partnership. All such tax payments made or caused to be
      made for or on behalf of the Partnership shall be made from Partnership
      funds.

      The Operator shall render for ad valorem taxation all property subject
      to this Agreement which by law should be returned for such taxes, and
      shall pay (or cause to be paid) all such taxes assessed thereon before
      they become delinquent. The Operator shall bring any unreasonable tax
      assessment to the attention of the Management Committee and, so directed
      by the Management Committee, shall protest any unreasonable tax
      assessment within the time and manner prescribed by law, and prosecute
      the protest to a final determination, unless the Management Committee
      directs the Operator to abandon the protest prior to final
      determination. When any such protested valuation shall have been finally
      determined, the Operator shall pay (or cause to be paid) the assessment,
      together with interest and penalty accrued. All ad valorem tax payments
      shall be made from Partnership funds.

4.7   Access to Partnership Tax Returns, Etc.
      Any tax returns which may be filed or any information concerning or upon
      which payments for taxes may be made by a Partner respecting the
      Partnership pursuant to this Article IV shall be subject to audit by the
      other Partner and both


                                      13



    




0147747.01



      Partners and any accountants or firms of accountants designated by such
      Partners shall at all reasonable times have access thereto.

4.8   Designation of Tax Matters Partner.
      Vulcan is designated the tax matters Partner as defined in Section
      6231(a)(7) of the Internal Revenue Code of 1954, as amended.

                                   ARTICLE V
                                  MANAGEMENT

5.1   Partners' Rights and Responsibilities.
      The Partners shall have equal rights in the direction and conduct of the
      business and affairs of the Partnership. The Partners covenant with one
      another that no action will be taken on behalf of or in the name of the
      Partnership without the consent of both Partners, except as otherwise
      expressly permitted herein.

5.2   Powers of the Partners.
      The Partners acting jointly through their respective representatives on
      the Management Committee shall possess all of the powers and rights of
      Partners under the partnership law of the State of Nevada, including,
      without limiting the generality of the foregoing, the power, on behalf
      of the Partnership and in their discretion, to:

      (a) Sell, assign, convey, or otherwise transfer title to any portion of
          the real and personal property and other assets of the Partnership,
          including any interest in


                                      14



    




           any mortgage, lease, or other interest in real or personal property
           owned by the Partnership;

      (b)  Construct or cause the construction of such buildings and other
           improvements upon land owned or leased by the Partnership, and such
           additions and alterations to existing improvements, as they deem
           proper;

      (c)  Lease to any party, including a Partner, upon such terms as they
           deem proper all or any portion of the real or personal property of
           the Partnership, whether or not the space or facility so leased is
           to be occupied by the lessee or, in turn, subleased in whole or in
           part to others;

      (d)  Borrow money for the Partnership, and, as security therefor,
           mortgage all or any part of the Partnership's real and personal
           property and in conjunction therewith execute all necessary papers
           and documents, including, but not limited to, bonds, notes,
           mortgages, pledges, security agreements and confessions of judgment
           for and on behalf of the Partnership;

      (e)  Open and close bank accounts, and name and change signatories
           authorized to make deposits and withdrawals in relation thereto;

      (f)  Obtain replacements of mortgages of the Partnership's property;

      (g)  Prepay, in whole or in part, refinance, recast, increase, modify,
           consolidate, correlate or extend on


                                      15



    




           such terms as they deem proper any mortgages affecting the real or
           personal property of the Partnership;

      (h)  Place record title to the Partnership's real or personal property
           in the name or names of a nominee or nominees for the purpose of
           mortgage financing or any other convenience or benefit to the
           Partnership;

      (i)  Employ from time to time persons, firms, financial advisors and
           corporations (including persons, firms and corporations which may
           be otherwise affiliated with a Partner), on such terms and for such
           compensation as they shall deem proper, to operate and manage the
           Partnership's property, including, without limitation, management
           agents, accountants and attorneys;

      (j)  Set aside investment funds of the Partnership for payment of past,
           current and future liabilities of the Partnership including, but
           not limited to, liabilities of the Partnership to individual
           Partners; and

      (k)  Execute, acknowledge and deliver any and all instruments to
           effectuate any of the foregoing powers.

No person, firm or corporation dealing with the Partnership shall be required
to inquire into the authority of the Partners acting through the Management
Committee to take any action or make any decision hereunder.

5.3   Delegation of Responsibility to Management Committee.
      Each Partner shall appoint two natural persons to represent that Partner
      on the Management Committee of the Partnership. The persons so appointed
      by each Partner shall be from time


                                      16




    




      to time herein called the "Partner's Representatives" on the Management
      Committee and any one of such representatives shall be called "Partner's
      Representative". The name of each such representative shall be notified
      to the other Partner by the Partner appointing same and any such
      representative may be removed by the appointing Partner, such removal
      being likewise notified to the other Partner. The Partners hereby
      delegate responsibility for the conduct of the business and affairs of
      the Partnership to the Management Committee.

5.4   Power of a Partner's Representative.
      Each Partner will take such action as is internally required within that
      Partner to provide each of its Partner's Representatives on the
      Management Committee sufficient authorization to bind and legally act on
      behalf of that Partner so long as his appointment remains in effect.
      Persons or entities dealing with the Partnership may rely upon the
      signatures of one representative of each Partner as binding upon the
      Partnership.

5.5   Management of the Partnership Business.
      The Management Committee shall conduct the property, affairs and
      business of the Partnership and shall make all decisions pertaining to
      the kind of business to be transacted (including decisions which expand
      or otherwise change the purpose of the Partnership as stated in Section
      1.3 above), the establishment of budgets for the Partnership, and the
      establishment of Partnership policies, including, but not



                                      17



    




      limited to, tax policies. In addition, the Management Committee may
      exercise on behalf of the Partners any of the powers of the Partners
      specified in Section 5.2 hereof. Unless otherwise specifically provided
      for herein, any decision of the Management Committee shall require the
      consent of all representatives on such Committee.

5.6   Rules of Procedure; Minutes; Secretary.
      The Management Committee may establish rules of procedure and policies
      pursuant to which it shall conduct its operations and proceedings. Such
      Committee may appoint a Secretary who shall be responsible for keeping
      the minutes of the proceedings and Committee decisions and for giving
      notice of the meetings of the Committee to each Partner's Representative
      in the manner provided herein. Such Secretary shall serve at the
      pleasure of the Partners, either one of which may cause his removal,
      effective upon the appointment and qualification of his successor, by
      the giving of written notice to the other Partner, in which event the
      Partners shall agree on such successor.

5.7   Management Committee Meetings.
      The Management Committee shall hold its meetings at such times, but at
      least quarterly, and places as it determines and shall have the
      Secretary specify by notice. Notice of each such meeting shall be
      communicated to each Partner's Representative by telephone or by mail,
      telegram or telex, addressed to him at his usual place of business at
      least fourteen (14) days if by mail or three (3) days if by


                                      18




    





      telephone, telegram or telex before the day on which the meeting is to
      be held; and such notice shall specify the time, place and general
      purpose of the meeting. The meeting shall not take place if either
      Partner is unable to be sufficiently represented and if that Partner
      communicates same to the other Partner and specifies an alternative
      date. In lieu of a formal meeting, any action required or permitted to
      be taken by the Management Committee may be taken in the form of a
      written consent thereto which shall have been signed by at least one
      representative of each Partner and filed with the minutes of the
      meetings of the Management Committee meetings.

5.8   Banking.
      A11 funds of the Partnership which are to be deposited with any
      financial institution shall be deposited in the name of the Partnership
      in such account or accounts as shall be designated by the Management
      Committee and withdrawals therefrom shall be made upon instruments
      signed by persons authorized by the Management Committee to make
      withdrawals.

5.9   Accounting and Auditors.

      (a)  Books of Account.
           The Partnership shall cause the Operator to maintain accounting
           records to show a true and complete record of the business, assets
           and liabilities of the Partnership according to generally accepted
           accounting principles in such form as the Management Committee
           shall from time to time approve or direct and shall


                                      19




    





           make such accounting records available for inspection to the
           Management Committee or to either Partner or any accountants or
           accounting firms designated by the Management Committee or by
           either Partner, at all reasonable times.

      (b)  Periodic Statements.
           The Partnership shall cause the Operator to prepare annual and
           quarterly financial statements (balance sheet and income statements
           and statements of changes in financial position), both in form and
           substance as dictated by generally accepted accounting principles,
           plus estimated monthly accounting data sufficient to allow monthly
           closings of Partnership accounting records. The annual financial
           statements shall be audited and certified by a national accounting
           firm selected by the Management Committee, and shall be submitted
           for review and approval by the Management Committee on an estimated
           basis not later than the end of February, and in final form not
           later than the end of March, in the year following the year to
           which they relate.

                                  ARTICLE VI
               CONSTRUCTION AND OPERATION OF THE VULCAN FACILITY

6.1   Construction and Operation of the Vulcan Facility.
      The Partners hereby agree that the Partnership shall
      designate Vulcan as the initial Operator to construct and


                                      20




    




      operate the Vulcan Facility pursuant to a certain Construction,
      Operating and Accounting Agreement between the Partnership and Vulcan
      dated as of August 30, 1985. The initial and any successor Operator may
      be removed from such position by unanimous vote of the Management
      Committee. Upon removal of an Operator, a successor shall be designated
      by unanimous vote of the Management Committee.

                                  ARTICLE VII
                               PARTNERSHIP TERM

7.1   Term.
      The term of the Partnership shall commence upon the date of this
      Agreement and shall expire on August 30, 2015, unless extended to a
      certain later date by mutual agreement of the Partners (such term and
      any such extension thereof being hereinafter called "the Partnership
      Term") or unless terminated earlier by the occurrence of any one or more
      of the following events:

          (a) The acquisition pursuant to Article VIII hereof, by one Partner
      of the entire interest in the Partnership owned by the other Partner;

          (b) The mutual written agreement of the Partners to dissolve the
      Partnership; or

          (c) The election, by a solvent Partner, to dissolve the Partnership
      upon the other Partner becoming insolvent, which, for the purposes
      hereof, shall be evidenced either by:


                                      21




    





         (1)  The filing by the other Partner or any parent entity
              thereof (hereinafter collectively the "Partner") of a voluntary
              petition in bankruptcy or the entry of a decree or order by a
              court having jurisdiction in the premises adjudging the Partner
              a bankrupt or insolvent, or approving as properly filed a
              petition seeking reorganization, arrangement, adjustment or
              composition of or in respect of the Partner under the Federal
              Bankruptcy Act or any other applicable federal or state law, or
              appointing a receiver, liquidator, assignee, trustee,
              sequestrator (or other similar official) of the Partner or of
              any substantial part of its property, or the ordering of the
              winding-up or liquidation of its affairs, said order or decree
              continuing unstayed and in effect for a period of sixty
              consecutive days; or

         (2)  The failure of the other Partner to make an initial capital
              contribution pursuant to Section 2.1(a) hereof or such
              additional capital contributions as may from time to time be
              called for pursuant to Section 2.1(c) hereof within ten (10)
              business days of receipt of a notice from the solvent Partner
              that such contribution has not been made within ten (10)
              business days of when due.


                                      22



    




In order to be effective, such election must be made within thirty (30) days
after the default specified in this Section 7.1(c).

                                 ARTICLE VIII
                       TRANSFER OF PARTNERSHIP INTEREST

8.1   Restriction on Transfer.
      During the Partnership Term no Partner shall, directly or indirectly in
      any manner, sell, transfer, assign, encumber or otherwise dispose of its
      interest in the Partnership, or any interest in the assets of the
      Partnership, without the prior written consent of the other Partner,
      except as provided in this Article. Further, no Partner shall, except
      with the prior written consent of the other Partner or except as
      provided for in Section 7.1(c) above, cause the dissolution of the
      Partnership.

8.2   Permitted Transfers.

      (a)  Mutually Agreed Transfers.
           In the event that the Partners mutually agree that one Partner
           ("the Purchaser") is to acquire the entire interest in the
           Partnership owned by the other ("the Seller") then, unless
           otherwise agreed between the Seller and the Purchaser:

           (1) The Seller shall sell its interest to the Purchaser for cash
               at a mutually agreed upon price and under such terms as the
               Partners may agree upon; and


                                      23




    




           (2) Following consummation of the sale of its interest in the
               Partnership, the Seller shall cease to have any further
               interest in the assets, rights (except that the validity of
               such other leases, service agreements, or other agreements to
               which Seller is also a party shall remain unimpaired thereby),
               or profits and losses of the Partnership and shall be
               indemnified by the Purchaser in respect of all liabilities and
               obligations of the Partnership as such exist as of said date of
               consummation of sale.

      (b)  Transfer to Related Entity.
           Each Partner shall have the right to transfer all (but not less
           than all) of its interest in the Partnership to a wholly-owned
           subsidiary thereof, to the corporate parent thereof, or to any
           other wholly-owned subsidiary of its corporate parent. In the event
           of such transfer, the Partner so transferring shall remain
           primarily liable for the performance by such transferee of
           transferor's Partnership obligations.

      (c)  Transfer to Third Parties.
           Each Partner shall have the right to transfer all (but not less
           than all) of its interest in the Partnership to a bona fide arms'
           length purchaser, if all of the following conditions are met:

           (1) The other Partner shall have been provided with a copy of the
               bona fide offer of purchase from a


                                      24



    




               third party and shall have been given, by written notice, a
               first right of purchase of the transferor's interest on terms
               equal to those of the proposed transfer, which terms shall be
               specified in such notice, and the other Partner shall either
               have declined same or have failed to have entered into, within
               90 days of said notice, a written agreement with the transferor
               Partner for the transfer of said interest on the terms
               specified in such bona fide offer of purchase;

           (2) The transferee is approved by the other Partner (which approval
               shall not be unreasonably withheld);

           (3) The transferee is acceptable to any entities which have
               lent money or extended other credit facilities to the
               Partnership; and

           (4) The transferee enters into a written agreement providing for
               said transfer which includes assumption by transferee of all of
               transferor's obligations in and to the Partnership, and which
               agreement has been approved by the other Partner (which
               approval shall not be unreasonably withheld).

      (d)  Transfers Subject to Section 4.4.
           Any transfer permitted pursuant to this Section 8.2 shall be subject
           to the restrictions contained in Section 4.4 hereof, which
           restrictions may require that


                                      25




    




           the transfer of all (but not less than all) of a Partner's interest
           in the Partnership be completed in one or more transactions.

8.3   Effect of Transfer.
      A Partner which transfers its interest in the Partnership in accordance
      with any provisions of this Article shall thereupon cease to be a party
      to this Agreement and shall have no further obligations hereunder and
      its transferee shall, by the agreement required in Section 8.2 above,
      thereupon be substituted in its place.

                                  ARTICLE IX
                 TRANSFER OF ASSETS OF PARTNERSHIP

9.1   Transfer of Goethermal Wells.
      The Partners, on behalf of the Partnership and upon the unanimous
      consent of the Management Committee, hereby agree to transfer to Vulcan,
      upon its request, any or all unneeded wells identified as such by an
      independent geothermal reservoir expert selected by Vulcan and approved
      by the Management Committee (the "Unneeded Wells"). The purchase price
      for the Unneeded Wells shall be equal to the original book value of such
      wells on Vulcan's books, inflated from the Closing Date through the date
      of purchase hereunder at a rate equal to the base rate on corporate
      loans at large U.S. money center commercial banks published by The Wall
      Street Journal plus one-half percent (l/2%), determined monthly in
      arrears (the "Interest Rate"). Said purchase price shall be


                                      26




    




      payable in sixty (60) equal monthly installments (or, at Vulcan's
      option, in a lesser number of equal monthly installments, but, in any
      event, with right of prepayment at any time without penalty), including
      interest calculated at the Interest Rate, commencing at the end of the
      month following the month of purchase hereunder.

                                   ARTICLE X
                 WINDING UP OF THE AFFAIRS OF THE PARTNERSHIP

10.1  Procedure Upon Ending of Partnership Term. Upon the expiration or
      termination of the Partnership Term, except pursuant to Section 7.1(c)
      above (which termination shall be governed by Section 10.2 below), the
      Partners, acting jointly through their respective representatives or, if
      one of the Partners is then in bankruptcy or receivership, the Partner
      who is not in bankruptcy or receivership, as the case may be, shall
      forthwith commence to wind up the affairs of the Partnership and the
      winding up shall be completed as promptly as possible. The proceeds from
      the liquidation of the assets of the Partnership (including the
      obligations of the Partners to the Partnership) shall be applied as
      promptly as is reasonably possible to the payment of the following in
      the order or priority in which they are listed:

      (a) Debts of the Partnership, other than to Partners;

      (b) Amounts owed to Partners, first on account of advances, and then on
          account of loans;



                                      27



    




      (c) The capital contributions of the Partners reduced by any current
          net loss; and

      (d)  The share of each Partner in undivided net profits, if any.

      Any profit or loss on disposition of Partnership properties or otherwise
      in the process of liquidation shall be credited or charged to the
      Partners in the manner provided in Section 3.2 above. Property shall be
      distributed in kind in the dissolution only to the extent the Partners
      (or their legal representatives, if any) agree upon such distribution
      and on the then present fair market value of such property. Such a
      distribution of property shall be treated for Partnership accounting
      purposes as though each item of property had been sold for cash equal to
      its value and the cash proceeds distributed to the Partner receiving
      that item of property. The difference between the value of the property
      distributed in kind and its book value shall be treated the same as a
      profit or loss on the sale of such property and shall be credited or
      charged to the Partners in the manner provided in Section 3.2 above. If
      in the process of winding up the Partnership affairs, a Partner should
      have a net debit balance in its capital account, whether by reason of
      losses in liquidation or otherwise, said debit balance shall represent
      an obligation from such Partner to the Partnership, which obligation
      shall be paid in cash within 30 days.


                                      28




    





      10.2 Procedure Upon Termination of Partnership Term by Solvent
      Partner.

      (a)  In the event the Partnership is terminated pursuant to Section
           7.1(c) above, then the solvent Partner shall have an option to
           purchase the Partnership interest of the insolvent Partner and
           shall pay as consideration therefor a price equal to the capital
           contributions(s) of the insolvent Partner plus:

           (1) Amounts owed to the insolvent Partner by the Partnership; plus

           (2) In the case of undivided net profits, the insolvent
               partner's share thereof; less

           (3) In the case of undivided net losses, the insolvent Partner's
               share thereof; and less

           (4) Amounts owed by the insolvent Partner to the Partnership.

           In order to be effective this option must be exercised by the
           solvent Partner within 30 days after the date on which an election
           has been made pursuant to Section 7.1(c) above.

      (b)  In the event the solvent Partner shall elect not to purchase the
           Partnership interest of the insolvent Partner, then the assets of
           Partnership shall be liquidated in accordance with the provisions
           of Section 10.1.


                                      29





    




                                  ARTICLE XI
                                 MISCELLANEOUS

11.1  Amendment.
      The parties hereto acknowledge that this Partnership Agreement contains
      the entire agreement between them with respect to the Partnership, that
      all prior documents, agreements and negotiations with respect to the
      Partnership are merged herein and superseded hereby, and any amendment
      to this Partnership Agreement shall be made in writing to and shall be
      executed by all of the then Partners.

11.2  Notices.
      Any notice or other instrument required or permitted to be given, made
      or sent under this Partnership Agreement shall be in writing, signed by
      the party giving or making the same, and shall be deemed duly given or
      made when personally delivered or on the fifth day after being mailed by
      prepaid registered or certified mail to the party entitled thereto at
      the addresses set forth on the first page hereof, or at such other
      addresses as the parties may specify by like notice.

11.3  Benefit.
      This Partnership Agreement shall be binding upon and operate for the
      benefit of the parties hereto and their respective successors and
      assigns.

11.4  Counterparts.
      This Partnership Agreement may be executed in any number of counterparts,
      each of which shall be deemed to be an



                                      30



    





      original, and such counterparts together shall constitute but one and
      the same Partnership Agreement. Anyone may rely upon a copy certified by
      a notary public commissioned under the law of the states of either
      Texas, Nevada or California to be a true copy of this Partnership
      Agreement (and of the attachments hereto) to the same effect as if such
      copy were an original. One copy of this Partnership Agreement and each
      amendment and supplement thereto shall at all times be kept on file at
      the principal place of business of the Partnership.

11.5  Applicable Law.
      This Partnership Agreement and the rights and obligations of the parties
      hereunder shall be interpreted in accordance with the laws of the State
      of Nevada. The descriptive titles of articles, sections and paragraphs
      of this Partnership Agreement are for convenience only and any
      construction of this Partnership Agreement shall be made without
      reference to such titles. In the event that any provisions of this
      Partnership Agreement violate any rule of law, only such invalid
      provisions and not this entire Partnership Agreement shall be considered
      void and of no effect and all of the other provisions hereof shall
      remain in full force and effect.

11.6  Injunctive Relief and-Specific Performance.
      A Partner's interest in this Partnership cannot readily be purchased or
      sold in the open market, and for that reason, among others, the parties
      may be irreparably damaged in the


                                      31




    




      event that this Partnership Agreement is not specifically enforced.
      Should any dispute arise concerning any possible disposition of such an
      interest in the Partnership, allegedly in violation of this Partnership
      Agreement, an injunction may be issued restraining such disposition
      pending the determination of such dispute. Likewise, any purchase and
      sale of any interest in the Partnership required by this Partnership
      Agreement, or any other transaction specified herein, shall be
      enforceable in a court having equity jurisdiction by an appropriate
      decree of specific performance.

11.7  Waiver of Terms.
      No waiver of any term or condition of this Partnership Agreement shall
      be effective unless made in a writing signed by the party against which
      enforcement of the waiver is sought. No such waiver shall be deemed to
      be a waiver of any subsequent breach of such term or condition, or of
      any breach of any other term or condition of this Partnership Agreement.


                                      32



    





IN WITNESS WHEREOF, the parties hereto have executed this Partnership
Agreement as of the day and year first above written.

ATTEST:                             VULCAN POWER COMPANY
                         (Seal)
 /s/ Joseph W. Aidlin               By: /s/ Andrew W. Hoch
- ----------------------------------     ------------------------------
Secretary                           Its: President
 Vulcan Power Company                   -----------------------------

ATTEST:                             BN GEOTHERMAL, INC.
                         (Seal)
 /s/ Michael D. Ferguson            By: /s/ Martin R. Engler, Jr.
- ----------------------------------     ------------------------------
Assistant Secretary                 Its: President
 BN Geothermal, Inc.                    -----------------------------




                                      33




    





                                ACKNOWLEDGMENT
                                --------------

STATE OF CALIFORNIA    )
                       )ss.
COUNTY OF LOS ANGELES  )


           On this 30th day of August, 1985, A.D., Joseph W. Audlin personally
appeared before me, a notary public in and for Los Angeles County, known or
proved to me to be the person described in and who executed the foregoing
instrument, who acknowledged to me that he or she executed the same freely and
voluntarily and for the uses and purposes therein mentioned.


                              /s/ April L. Taylor
                              ------------------------------
                              Notary Public in and for said
                              County and State

                              Commission Expires: August 2, 1988



                                      34




    





                                   AGREEMENT
                                      AND
                   AMENDMENT NO. 1 TO PARTNERSHIP AGREEMENT

           This Agreement and Amendment No. 1 to Partnership Agreement is made
and entered into as of the 15th day of December, 1988, by and between Vulcan
Power Company, a Nevada corporation ("Vulcan"), and BN Geothermal Inc., a
Delaware corporation ("BNG").

           WHEREAS, Vulcan and BNG entered into the Partnership Agreement
dated as of August 30, 1985 (the "Partnership Agreement"), for the primary
purpose of acquiring, constructing, owning and operating a single
geothermal-electric generating facility;

           WHEREAS, Burlington Resources Inc. ("BRI"), the owner of record of
all the issued and outstanding shares of capital stock of BNG (the "BNG
Shares"), has entered into an agreement with Mission Energy Company
("Mission") dated as of June 16, 1988 (the "Stock Purchase Agreement")
providing for the sale by BNI and the purchase by Mission of the BNG Shares;

           WHEREAS, Mission has conditioned its obligations under the Stock
Purchase Agreement upon the execution of this Agreement;

           WHEREAS, BNG has agreed to amend, and seek Vulcan's agreement to
amend, the Partnership Agreement as herein provided to facilitate the sale of
the BNG Shares to Mission; and

           WHEREAS, Vulcan has agreed to so amend the Partnership Agreement;

           NOW THEREFORE, consideration of the mutual covenants hereinafter
set forth and other good and valuable consideration, receipt of which is
hereby acknowledged, Vulcan and BNG agree as follows:

           1. Default in Capital Contributions. Section 2.1(c) and Section 3.2
of the Partnership Agreement each shall be amended to delete the second
sentence thereof. Section 3.3 of the Partnership Agreement shall be amended in
its entirety to read as follows:

      "3.3 Default in Capital Contributions

           In the event that a partner does not make a timely additional
      capital contribution as required by Section 2.1(c) above ("Defaulting
      Partner"), the other general partner ("Non-Defaulting Partner"), at its
      option, may pay to the Partnership an amount (the "Non-Defaulting
      Partner Payment"), up to or equal to the unfunded amount, which






    




      payment shall be deemed to be a capital contribution from the Defaulting
      Partner to the Partnership. Notwithstanding any other provision of this
      Partnership Agreement, in the event that a Non-Defaulting Partner makes
      a Non-Defaulting Partner Payment, the Partnership shall not make any
      distribution to the Defaulting Partner, but shall pay all distributions
      (the "Defaulting Partner Distributions") which would otherwise have been
      paid to the Defaulting Partner to the Non-Defaulting Partner until (i)
      the amount of all Defaulting Partner Distributions paid to the
      Non-Defaulting Partner equals the amount of the Non-Defaulting Partner
      Payment plus an amount equal to the maximum lawful rate of interest on
      the unreimbursed balance thereof (the "Additional Amount") or (ii) the
      Non-Defaulting Partner notifies the Partnership that it has received a
      payment from the Defaulting Partner equal to the amount of the Non-
      Defaulting Partner Payment plus the Additional Amount, less the amount
      of any previous distributions to the Non- Defaulting Partner with
      respect to such default. During any period in which Defaulting Partner
      Distributions are being paid to the Non-Defaulting Partner, at the
      Non-Defaulting Partner's option, the Defaulting Partner's members on the
      Management Committee shall not have any voting rights and the vote of
      the Non-Defaulting Partner shall be sufficient with regard to any matter
      voted on by the Management Committee. The Defaulting Partner shall be
      liable to the Partnership and to the Non-Defaulting Partner for all
      losses, damages and expenses sustained or incurred by the Partnership
      and such Non-Defaulting Partner as a result of the Defaulting Partner's
      failure to fund its required contribution and such default, including,
      without limitation, any additional tax liabilities and interest or
      penalties thereon."

In addition, Section 7.1(c)(2) and Section 10.2 of the Partnership Agreement
shall be amended to substitute (i) the phrase "Non-Defaulting Partner" for the
phrase "solvent partner" or "solvent Partner" and (ii) the phrases "Defaulting
Partner['s]" for the phrases "insolvent Partner['s]".

           2.   Capital Accounts.  Section 2.2 of the Partnership Agreement
shall be amended in its entirety to read as follows:

      "2.2 Partners' Capital Accounts

           (1) The Partners' capital accounts have been adjusted to reflect
      the fair market value of the Partnership property in accordance with the
      rules set forth in Treasury Regulation Section 1.704-1(b)(2)(iv)(r).
      Partners' capital accounts shall be maintained in accordance with
      Treasury Regulation Section 1.704-1(b)(2)(iv). The capital account of
      each Partner shall be credited with (i) the dollar amount of any capital
      contributions made by such Partner, (ii) the fair market value of
      property contributed by such Partner to



                                      2



    




      the Partnership (net of liabilities secured by such contributed property
      that the Partnership is considered to assume or take subject to under
      Internal Revenue Code Section 752), (iii) the amount of any income,
      gain, profit, or tax exempt income allocated to such Partner pursuant to
      Section 4.2 below, and (iv) the Partner's share of any basis increases
      required by Internal Revenue Code Sections 48(q) and 1016(a)(22). The
      capital account for each Partner shall be decreased by (i) the amount of
      any loss or other deduction allocated to such Partner pursuant to
      Section 4.2 below, (ii) the amount of money and the fair market value of
      all property distributed to such Partner (net of liabilities assumed by
      such Partner or to which the property is subject), (iii) any Internal
      Revenue Code Section 705(a)(2)(B) expenditures and Section 709
      nondeductible and nonamortizable items allocated to such Partner, and
      (iv) the Partner's share of any basis decreases required by Internal
      Revenue Code Sections 48(q) and 1016(a)(22).

                At the discretion of the Management Committee, the Partners'
      capital accounts will be adjusted to reflect a revaluation of
      Partnership property (including intangible assets such as goodwill) on
      the Partnership's books in accordance with Treasury Regulation Section
      1.704(b)(2)(iv)(f) upon (i) the contribution of money or other property
      (other than a de minimis amount) to the Partnership by a new or existing
      Partner as consideration for an interest in the Partnership or (ii) in
      connection with the liquidation (including a constructive liquidation)
      of the Partnership or a distribution of money or other property (other
      than a de minimis amount) by the Partnership to a retiring or continuing
      Partner as consideration for an interest in the Partnership."

           3.   Distributions.  Section 2.4 of the Partnership Agreement shall
be amended in its entirety to read as follows:

           "Distributions to Partners shall be made quarterly on the 45th day
           of each calendar quarter in such amounts as the Partners acting
           jointly may determine to be in the best interest of the
           Partnership; provided, however, that the net cash proceeds received
           by the Partnership as a result of the sale by the Partnership of
           its assets (or a portion thereof), whether pursuant to a purchase
           agreement granted by the Partnership to a Partner or otherwise,
           shall be first applied to retire the outstanding debts of the
           Partnership and any residual amount (after provision considered
           appropriate by the Partners for taxes, replacements and other
           expenses of the partnership related to such sale) shall be
           immediately distributed to the Partners in equal proportion, unless
           the Partners shall agree otherwise. Except as provided in Section
           3.3, no interest shall be paid to a Partner on its capital in the
           Partnership."


                                      3




    




           4.  Tax Allocations.  Section 4.2 of the Partnership Agreement
shall be amended in its entirety to read as follows:

           "Each item of income, gain, loss or deduction shall be allocated to
           each Partner in accordance with Internal Revenue Code Section
           704(b) and the regulations promulgated thereunder, as follows:

               (a) All amounts received by the Partnership constituting gross
           income shall be allocated to the Partners in proportion to their
           respective interests in profits and losses of the Partnership as
           provided in Section 3.2;

               (b) Exploration cost, intangible drilling cost ("IDC"), and
           operating and maintenance costs shall be allocated to the Partners
           in proportion to their respective interests in profits and losses
           of the Partnership as provided in Section 3.2;

               (c) With respect to depreciable assets purchased by the
           Partnership, depreciation shall be allocated to the Partners in
           proportion to their respective interests in profits and losses of
           the Partnership as provided in Section 3.2;

               (d) Amortization of intangible assets shall be allocated to
           each Partner as follows:

               (1)   With respect to intangible assets which were contributed
                     by a Partner at the formation of the Partnership, any
                     amortization will be allocated entirely to such Partner;
                     and

               (2)   With respect to all other intangible assets, amortization
                     will be allocated to the Partners in proportion to their
                     respective interests in profits and losses of the
                     Partnership as provided in Section 3.2;

                (e) Loss upon the sale, exchange, distribution, abandonment or
           other disposition of property shall be allocated to the Partners in
           proportion to their respective interests in profits and losses of
           the Partnership as provided in section 3.2;

                (f) Gain upon the sale, exchange, distribution, or other
           disposition of property shall be allocated to the Partners in
           proportion to their respective interests in profits and losses of
           the Partnership as provided in Section 3.2;


                                      4





    




                (g) Costs or expenses of any other kind shall be allocated to
           the Partners in proportion to their respective interests in profits
           and losses of the Partnership as provided in Section 3.2;

                (h) All deductions and credits attributable to property
           eligible for the regular investment tax credit or the energy tax
           credit percentage shall be allocated to the Partners in proportion
           to their respective interests in profits and losses of the
           Partnership as provided in Section 3.2;

                (i) Any recapture of depreciation, IDC, and any other item of
           deduction or credit shall, to the extent possible, be allocated
           among the Partners in accordance with their sharing of the
           depreciation, IDC or other item of deduction or credit which is
           recaptured; and

                (j) Income, gain, loss and deduction with respect to property
           contributed to the Partnership by a Partner shall be shared among
           the Partners, pursuant to Treasurer Regulations promulgated under
           Section 704(c) of the Code, so as to take account of the variation,
           if any, between the basis of the property to the Partnership and
           its fair market value at the time of the contribution."

           5. Transfers of Partnership Interest. Section 8.2 of the
partnership Agreement shall be amended by changing the designation of
paragraph (d) of such Section to paragraph (f) and adding the following
paragraphs (d) and (3) after paragraphs (c) of such Section:

           "(d) Transfer of Partial Interest to Third Party; Of Limitations.

                (i) Notwithstanding anything in this Agreement to the
           contrary, if the Federal Energy Regulatory Commission proposes to
           decertify the Vulcan Facility as a Qualifying Small Power
           Production Facility (a "Qualifying Facility") under the Federal
           Power Act and the Public Utility Regulatory Policies Act of 1978,
           each as amended, and the regulations promulgated thereunder, based
           on the grounds that, as a result of an amendment or modification to
           the ownership criteria of 18 C.F.R. Section 292.206 (the "Ownership
           Criteria") or the interpretation thereof, which become effective
           subsequent to the certification of the Vulcan Facility as a
           Qualifying Facility, the Ownership Criteria are not satisfied
           because of a Partner's interest in the Vulcan Facility, then such
           Partner (the "Noncomplying Partner") shall have the right (a) to
           convert the Partnership to a Nevada limited partnership, with the
           consent of the other Partner (the "Complying Partner"),


                                      5




    




           which consent shall not be unreasonably withheld, and (b) to
           convert to limited partner interests in the Partnership ("Limited
           Interests") the portion of its general partner interest in the
           Partnership necessary to satisfy the Ownership Criteria (the
           "Necessary Interest") and to transfer to a single third party such
           Limited Interests. In the event the Noncomnlying Partner does not
           elect to convert the Partnership to a Nevada limited partnership or
           the Complying Partner does not consent to such election, the
           Noncomplying Partner shall have the right to transfer to a single
           third party the Necessary Interest, provided that all of the
           Following conditions are satisfied:

                (a) The Complying Partner shall have been provided with a copy
           of the bona fide offer of purchase from any third party and shall
           have been given, by written notice, a first right of purchase of
           the Necessary Interest on terms equal to those of the proposed
           transfer, which terms shall be specified in such notice, and the
           Complying Partner shall have (1) declined to exercise such right of
           first purchase, (2) failed to notify the Noncomplying Partner
           within 5 days of such notice of its decision to exercise such right
           or (3) failed to complete a purchase of the Necessary Interest
           within 15 days of such notice;

                (b) The transferee of the Necessary Interest enters into a
           written agreement providing for said transfer which includes
           assumption by such transferee of the Noncomplying Partner's
           obligations, in proportion to the interest being transferred to
           such transferee, in and to the Partnership; and

                (c) Section 5.7 of this Agreement shall be amended to provide
           for decisions of the Management Committee to be made by approval of
           the representatives of partners holding 65% of the interests of the
           Partnership.

                (ii) Notwithstanding anything in this Agreement to the
           contrary, if a Partner fails to make a timely capital contribution
           as required by Section 2.1(c), then the other Partner shall have
           the right, but not the obligation, in addition to its option
           pursuant to Section 3.3, (a) to convert the Partnership to a Nevada
           limited partnership and (b) to convert any portion of its general
           partner interest in the Partnership to Limited Interests and to
           transfer such Limited Interests to one or more third parties.

           "(e) Restrictions on Encumbrances of Partnership Interests.
                Notwithstanding the foregoing," in no event may any Partner
                assign, convey, mortgage,


                                      6




    




                pledge, sell, transfer or otherwise dispose of all or any part
                of its interest in the Partnership under this Agreement to, or
                merge with, sell assets to, sell stock to, consolidate with or
                combine with, any person whose ownership of an interest in the
                Partnership or under this Agreement would cause the Vulcan
                Facility not to be a qualifying facility within the meaning of
                18 C.F.R. Section 292.203."
Line 1 of Section 8.3 of the Partnership Agreement shall be amended to insert
the words "all of" after the word "transfers".

Article VIII of the Partnership Agreement shall be further amended by adding a
new Section 8.4 and Section 8.5 at the end thereof to read in its entirety as
follows:

      "8.4 Change in Control. Except as otherwise permitted pursuant to
      Section 8.2, no Partner may, without the consent of the other Partner,
      (a) sell transfer, pledge, encumber, assign or otherwise hypothecate its
      interest in the Partnership if such act would result in a change of
      control of the Partnership, or (b) permit a change in control of such
      Partner (other than in the course of a reorganization, merger,
      consolidation or public offering involving (i) creation of a holding
      company, or (ii) corporate spin-offs or split-offs). For purposes of
      this subsection only, control shall mean ownership, direct or indirect,
      of more than fifty percent (50%) of the outstanding voting securities of
      a Partner by an entity which itself is not owned, directly or
      indirectly, more than fifty percent (50%) by any other entity.

      "8.5 Obligation to Restore Deficit Capital Account

           Any transfer permitted under this Agreement of a Partner's interest
      in the Partnership shall be subject to the provisions of Section 10.1."

           6. Right of First Refusal to Purchase Electricity. The title of
Article IX shall be amended by adding the words "AND RIGHT OF FIRST REFUSAL TO
PURCHASE" after the words "TRANSFER OF". A new Section 9.2 shall be added
which shall read in its entirety as follows:

      "9.2  Right of First Refusal to Purchase Electricity. In the event that
      the Vulcan Facility produces electrical energy in excess of that which
      can be sold to Southern California Edison Company ("SCE") (such excess,
      the "Excess Electricity"), then Magma Power Company ("Magma") shall have
      the right of first refusal to purchase the Excess Electricity or any
      portion thereof on substantially similar price, terms and conditions
      that the Partnership may sell to any third party in an arms length
      transaction, f.o.b. the Partnership's generating facility. The
      Partnership shall


                                      7



    




      give Magma written notice of the price, terms and conditions of the
      proposed sale of Excess Electricity. If Magma fails to exercise its
      right of first refusal to purchase the Excess Electricity within 15 days
      of the receipt of such written notice, said right of first refusal shall
      expire. Any such sale of the Excess Electricity to Magma pursuant to
      this Section 9.2 is expressly conditioned on the prior written consent
      of SCE as required by the Partnership's power purchase contract with
      SCE. Notwithstanding anything in this Section 9.2 to the contrary, Magma
      shall not be given the right of first refusal to purchase the Excess
      Electricity or any portion thereof and shall not be entitled to purchase
      the Excess Electricity or any portion thereof if such right or such
      purchase would contravene any law or agreement by which the Partnership
      or its assets are bound, cause the Vulcan Facility to lose its status as
      a Qualifying Small Power Production Facility under the Federal Power Act
      and the Public Utility Regulatory Policies Act of 1978, each as amended,
      and the regulations promulgated thereunder, cause the Partnership or the
      Vulcan Facility to be regulated as a utility under state or federal law,
      violate or conflict or interfere with any rights of third parties, or
      impair any assets of the Partnership."

           7.   Procedure Upon Ending of Partnership Term.
Section 10.1 is amended to delete the last paragraph of such Section and add
the following in its place:

      "Any profit or loss on disposition of Partnership Properties or
      otherwise in the process of liquidation shall be credited or charged to
      a Partner as follows:

      (i)  First, to each of the Partners to the extent of and in proportion
      to the deficit balance, if any, in their capital accounts;

      (ii) Second, to each of the Partners in proportion to and to the extent
      of the minimum amount required to equalize the capital accounts of the
      Partners in proportion to their interests in the Partnership as provided
      in Section 3.2; and

      (iii)  Third, to the Partners in the manner provided in Section 3.2.

      Property shall be distributed in kind in the dissolution only to the
      extent the Partners (or their legal representatives, if any) agree upon
      such distribution and on the then present fair market value of such
      properties. Such distribution of property shall be treated for
      Partnership accounting purposes as though each item of property has been
      sold for cash equal to its value and the cash proceeds distributed to
      the Partner receiving that item of property. The difference between the
      value of property distributed in kind and its book value shall be
      treated the same as a


                                      8




    




      profit or loss on the sale of such properties and shall be credited or
      charged to the Partners in the manner provided above. If a Partner has a
      deficit balance in its capital account at the time of the liquidation of
      the Partnership or the liquidation of its interest in the Partnership
      (after crediting allocations of gross income and debiting allocations of
      loss and deduction to its capital account) such Partner must pay to the
      Partnership the amount of the deficit balance. This amount, upon the
      liquidation of the Partnership, will be paid to the creditors of the
      partnership or distributed to the other Partner in accordance with its
      positive capital account balances in accordance with Section
      1.704-1(b)(2)(ii)(b)(3) of the Treasury Regulations. The payment must be
      made in readily available funds no later than the end of the taxable
      year of the liquidation of a Partner's interest in the Partnership (or,
      if later, within 30 days after the date of the liquidation). The
      Partners intend that the provisions set forth in this paragraph will
      constitute an unconditional obligation to restore deficit capital
      accounts as described in Section 1.704-1(b)(2)(ii)(b)(3) of the Treasury
      Regulations. The regulations will control in the case of any conflict
      between those regulations and this Section 10.1."

           8.   Technical Amendments.  All references in the Partnership
Agreement to the "Internal Revenue Code of 1954, as amended" shall be amended
to read the "Internal Revenue Code of 1986, as amended."

           9.   Miscellaneous.

           (a) This Agreement may be executed in any number of counterparts,
      each of which shall constitute an original, and all of which, when taken
      together, shall constitute one agreement.

           (b) All headings appearing in this Agreement are for convenience of
      reference only and shall be disregarded in construing this Agreement.

           (c) If any provision hereof is determined to be illegal or
      unenforceable for any reason, the remaining provisions hereof shall not
      be affected thereby.

           (d) Capitalized terms not otherwise defined herein shall have the
      meanings assigned to them in the Partnership Agreement.

           (e)  This Agreement is for the benefit of the respective parties
      and of Mission.

           (f)  This Agreement shall be effective as of the Closing under the
      Stock Purchase Agreement.



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           IN WITNESS WHEREOF, Vulcan and BNG have executed this Agreement as
of the day and year first above written.



                              VULCAN POWER COMPANY


                              By /s/ John R. Peele
                                --------------------------------
                              Its    Vice President
                                 -------------------------------

ATTEST: /s/ Wallace D. Dieckman
       ----------------------
       Assistant Secretary

                              BN GEOTHERMAL INC.


                              By /s/ L. Edward Parker
                                --------------------------------
                              Its    President
                                 -------------------------------

ATTEST: /s/ Wallace D. Dieckman
       ----------------------
       Attorney


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