**Exhibit
      10.11**




**MATAMOROS
      LPG MIX PURCHASE AND SALES AGREEMENT**






**BETWEEN**






**RIO
      VISTA OPERATING PARTNERSHIP L.P. AND P.M.I. TRADING
      LIMITED**




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This
      Matamoros LPG Mix Purchase and Sales Agreement (the "Agreement"), made and
      entered into as of April 28 th ,
      2006,
      by and between Rio Vista Operating Partnership L.P., a corporation organized
      under the laws of the State of Delaware, United States of America, having its
      principal place of business at 820 Gessner Road, Suite 1285, Houston Texas,
      77024, United States of America ("Seller") and P.M.I. Trading Limited, a
      corporation organized under the laws of Ireland, having the administration
      of
      its business and place of address at Av. Marina Nacional No. 329, Torre
      Ejecutiva Piso 20, Col. Huasteca, C.P. 11311, in Mexico City, Mexico ("Buyer")
      (each of Buyer and Seller, "Party" and, collectively, the
      "Parties").





**NOW,
      THEREFORE,** in
      consideration of the representations, warranties, covenants and agreements
      hereinafter set forth, the Parties hereby agree as follows:





**ARTICLE
      I**


**DEFINITIONS**





**1.01** **Definitions.** **** For
      purposes of this Agreement, the following terms shall have the meanings
      indicated below:





"Affiliate"
      shall mean, with respect to any Person, any other Person controlling, controlled
      by, or under common control with such Person;





"Agreement"
      shall mean this Agreement, including all Exhibits attached hereto, as the same
      may be amended, modified or supplemented from time to time;





"Alternative
      Delivery Point" shall mean Seller's terminal located at 902 Chemical Road,
      Port
      of Brownsville, 78521 Texas, United States of America.;





"ASTM"
      shall mean the American Society for Testing and Materials;





"Banking
      Day" shall mean any day on which the banks are open for business in the
      jurisdiction in which payment is to be made;





"Butane"
      shall comply with the specifications set forth by the GPA;





"Buyer's
      Representatives" shall mean Pemex-Gas y Petroquímica Básica's
      personnel
      authorized to supervise the operations described in this Agreement at the
      Delivery Point or at the Alternative Delivery Point;





"DDU"
      shall mean Delivered Duty Unpaid, according to Incoterms 2000;





"Day"
      shall mean a twenty-four (24) hour period, starting at zero hours **** local
      time in Matamoros on the morning of each calendar day and ending **** at
      zero
      hours local time in Matamoros on the morning of the following calendar
      day;


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"Delivery
      Point" shall mean Seller's terminal located at Carr. Sendero Nacional Km. 9,
      desviación Carr. La Rosita-Lucio Blanco Km. 3.4, desviación brecha 22 s/n (a 500
      mts.), Ejido La Gloria, C.P. 87560, Matamoros, Tamaulipas, México;





"FCA"
      shall mean Free Carrier, according to Incoterms 2000;





"Gallon(s)"
      shall mean one (1) U.S. standard gallon of two hundred and thirty one (231)
      cubic inches at sixty degrees Fahrenheit (60°F);





"GPA"
      shall mean the Gas Processors Association;





"Injection
      Point" shall mean Seller's terminal located at 902 Chemical Road, Port of
      Brownsville, Texas, 78521, United States of America;





"Product"
      shall mean the LPG Mix meeting the specification parameters set forth in Exhibit
      A.





"Mexico"
      shall mean the United Mexican States;




"MMgal"
      shall mean millions of Gallons;





"Month"
      shall mean a calendar month;





"Person"
      shall mean an individual, partnership, company, firm, trust, joint venture,
      unincorporated organization or government or any department or agency
      thereof;





"PGPB"
      shall mean Pemex-Gas y Petroquímica Básica;





"U.S.
      Dollars" or "U.S.$" shall mean dollars of the United States of
      America;





"U.S."
      shall mean the United States of America.


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**ARTICLE
      II**


**PURPOSE;
      TERM**





**2.01** **Purpose.** Seller
      agrees to sell, transfer, convey and deliver to Buyer and Buyer agrees to
      purchase and accept receipt from Seller, of Product in accordance with the
      terms
      and conditions of this Agreement.





**2.02** **Term.** Unless
      earlier terminated in accordance with this Agreement, the term of this Agreement
      (the "Term") shall commence on May 1 st ,
      2006
      (the "Effective Date") and end on March 31 st ,
      2007.





**ARTICLE
      III**




**PRODUCT**





**3.01** **Product
      Specifications.** Product
      shall, at all times, meet the specification parameters set forth in Exhibit
      A.





Seller
      warrants and guarantees that (i) the Product will conform to the specifications
      described in Exhibit
      A at the
      time and place of delivery; (ii) that Seller has free and clear title to the
      Product sold hereunder, and (iii) that the Product shall be delivered to Buyer
      free from security interests, liens or other encumbrances.





**3.02** **Product
      Quantity.** **** In
      accordance with the following table:





5
                MMgal per Month
              +/-
                10% at Buyer's option
            FROM
                MAY 1stTHROUGH SEPTEMBER 30th,
                2006.9
                MMgal per Month
              +/-
                10% at Buyer's option
            FROM
                OCTOBER 1stTHROUGH NOVEMBER 30th,
                2006.10
                MMgal per Month
              +/-
                10% at Buyer's option
            FROM
                DECEMBER 1st2006 THROUGH JANUARY 31st,
                2007.9
                MMgal per Month
              +/-
                10% at Buyer's option
            FROM
                FEBRUARY 1stTHROUGH MARCH 31st,
                2007.





Ten
      (10)
      Days prior to the beginning of each Month, Buyer shall inform to Seller the
      volume to be delivered on such Month ("Nominated Volume").





**3.02.1**  **Early
      Termination.** **** If
      this
      Agreement is terminated by either Party prior to the expiration of the Term
      in
      accordance with the terms and conditions of this Agreement, Nominated Volume
      shall be prorated through the termination date on the basis of this Article
      3.02.





**3.03**  **Product
      Quality and Quantity Inspection.** **** Buyer
      and
      Seller shall appoint an independent inspection company the ("Inspector")
      mutually agreeable to Buyer and Seller to determine quality and quantity of
      the
      Product at the Delivery Point. The Inspector's findings shall be final and
      binding on the **** Parties
      in the absence of fraud, bad faith or manifest error. Buyer shall pay the gross
      amount of the Inspector's fees, however Seller agrees that Buyer shall monthly
      deduct the amount of U.S.$8,500.00 from amounts due to Seller, such amount
      representing Seller's share of the Inspector's fees.


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**3.03.1**  **Product
      Quality Inspection.** **** All
      Product shall be monitored to ensure compliance with the specification
      parameters in Exhibit
      A. Determination of quality shall follow the procedures set forth in the latest
      revision of ASTM procedures (the "Compliance Procedures"). A sample of Product
      will be drawn in accordance with the Compliance Procedures (the "Sampling")
      by
      the Inspector at the Delivery Point for approximately every 50,000 Gallons
      injected at the Injection Point. A gas chromatography ("GC") analysis (as
      defined hereunder) shall be performed by the Inspector on the sample in
      accordance with the ASTM D-2163 method to assess the sample's compliance with
      the specification parameters in Exhibit
      A. If the
      sample analysis is found to be non-compliant, the entire 50,000 Gallons of
      Product, from which the sample was taken, will be deemed non-compliant (the
      "Non-Compliant Product"), and the Inspector shall immediately notify both
      Parties. All Non- Compliant Product shall be deemed not delivered and Buyer
      shall not be responsible for payment unless both parties agree to receive such
      volumes. Seller shall use its best efforts to dispose of any Non-Compliant
      Product promptly upon notification of its non-compliance by the Inspector and
      shall be responsible for any and all costs and liabilities relating to or
      arising from the Non- Compliant Product. The gas chromatograph utilized shall
      be
      calibrated in accordance with the latest ASTM and GPA procedures.





**3.03.2**  **Product
      Quantity Inspection.** **** The
      Inspector shall determine the quantity of Product for payment purposes as
      follows:





(a)  Each
      empty tank truck shall be weighed on the platform scale at the Delivery
      Point/Alternative Delivery Point, or an alternative independent platform scale
      mutually acceptable to the Parties. Once Product is completely loaded onto
      the
      tank trucks, such tank truck will be weighed at the same platform scale upon
      its
      departure. The weight obtained by the differential between these two
      measurements shall be converted into volume in Gallons and corrected at 60°F in
      accordance with the Compliance Procedures, through the determination of the
      specific gravity through gas chromatograph provided by Seller or by
      Inspector.





(b)  Seller's
      terminal platform scale at the Delivery Point/Alternative Delivery Point will
      be
      tested and adjusted for accuracy at least once every six (6) Months. Seller
      will
      be required to comply with the calibration and certification **** procedures
      adopted by Mexican authorities in accordance with Official Standards
      (NOM-010-SCFI latest version). Buyer's Representatives and Inspector may witness
      the calibration and certification procedures. Seller shall provide Buyer via
      fax
      a copy of the above-mentioned certificates. If Seller's terminal platform scale
      at the Delivery Point/Alternative Delivery Point is used, and/or any claim
      is
      received by Buyer from PGPB, Buyer reserves the following rights: To execute
      evaluation procedures on a random basis sending tank trucks to an independent
      scale to test the accuracy of such scale and recover damages from Seller for
      any
      discrepancy found.


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(c)  If
      Seller's platform scale at the Delivery Point/Alternative Delivery Point is
      not
      suitable for the service due to non- compliance with the above-mentioned
      Official Standards and an independent platform scale is used, the Parties will
      share equally the cost of weighing the tank trucks before and after
      loading.





(d)  If
      Seller
      at any time replaces the platform scales at its terminal at the Delivery
      Point/Alternative Delivery Point, such new scales shall be used to weigh all
      tank trucks receiving Product at the Delivery Point/Alternative Delivery Point,
      and shall be operated and maintained in accordance with the above provisions.
      Seller shall be responsible for all costs and expenses associated with such
      new
      scales.





(e)  For
      customs and inventory-management purposes, Product pumped through Seller's
      pipeline from the Injection Point to the Delivery Point shall be measured on
      a
      daily basis at the micromotion measurement device installed at the Delivery
      Point. Readings by such device shall be registered by the Inspector, Mexican
      authorities, PGPB's customs broker, Buyer's Representative and Seller's
      representative. A reading of the quantity of Product pumped will be calculated
      on the basis of the differential between the readings taken at 00:00 hrs. and
      the reading taken the previous Day at 00:00 hrs., converted to volume in Gallons
      and corrected at 60°F, through the determination of the specific gravity by
      samples taken at the Delivery Point (at the micromotion measurement device
      installed at the connection point between Seller's pipeline and the Delivery
      Point) for approximately every 50,000 Gallons received at the Delivery Point,
      through GC.





Additionally,
      for verification and customs purposes, Product pumped through Seller's pipeline
      from the Injection Point to the Delivery Point shall be measured on a weekly
      basis every Monday at the micromotion measurement device installed at the
      Delivery Point. Readings by such device shall be witnessed by the Inspector,
      Mexican authorities, PGPB's customs broker Buyer's Representative and Seller's
      representative. A reading of **** the
      quantity of Product pumped will be calculated on the basis of the differential
      between the current reading and the reading taken the previous Monday at the
      same time converted to volume in Gallons and corrected at 60°F, through the
      determination of the specific gravity by samples taken at the Delivery Point
      (at
      the micromotion measurement device installed at the connection point between
      Seller's pipeline and the Delivery Point) for approximately every 50,000 Gallons
      received at the Delivery Point on the immediate preceding five (5) Days, through
      GC. The Inspector shall take line samples and shall test the batch pumped at
      the
      time of the readings.


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**ARTICLE
      IV**


**PRODUCT
      DELIVERY; TRANSFER OF TITLE; CUSTODY**


**RISK
      OF LOSS AND CONTAMINATION**





**4.01**  **Product
      Delivered at Delivery Point.** **** Product
      shall be
      delivered DDL) at the Delivery Point. Title of Product shall pass from Seller
      to
      Buyer at the point in the Seller's pipeline where Product passes into México at
      the U.S./México border in Matamoros, Tamaulipas, México. The custody, risk of
      loss and contamination with respect to Product shall pass from Seller to Buyer
      at the moment Product passes the flange connection between the Delivery Point
      hose and the tank trucks provided by Buyer.





**4.02**  **Product
      Delivered at the Alternative Delivery Point.** **** If,
      by
      any reason of a programmed maintenance at the Delivery Point or Injection Point,
      or an event different from Force Majeure at the Delivery Point, Seller is not
      able to deliver Product at the Delivery Point, Seller shall immediately notify
      Buyer, and Buyer shall have the option of loading Product at the Alternative
      Delivery Point, in which case Buyer shall so notify Seller. The Product shall
      be
      then delivered FCA at the Alternative Delivery Point. Title of Product, as
      well
      as custody, risk of loss and contamination with respect to Product shall pass
      from Seller to Buyer as the Product passes the flange connecting the Seller's
      Alternative Delivery Point with Buyer's tank trucks.





For
      Product delivered at the Alternative Delivery Point, Buyer shall nominate tank
      truck transportation services. Seller shall discount from the sales price,
      the
      Service Fee described in Article 5.01 and 5.02, by an amount equal to the
      transportation costs incurred by Buyer, such transportation costs to be
      determined based on the prevailing market conditions at the time that Buyer
      must
      arrange for transportation and as mutually agreed by the Parties.





In
      the
      event of a Force Majeure condition at the Delivery Point, Buyer shall also
      have
      the option of loading Product at the Alternative Delivery Point. The Parties
      agree that in this event, Seller shall discount from the Product's price
      (including the Service Fee), as set forth in Article 5.01 and 5.02, an amount
      equal to the operational costs of the terminal at the Delivery Point plus costs
      related to the transportation of Product through Seller's pipeline from the
      Alternative Delivery Point to the Delivery Point. Seller shall inform Buyer
      of
      its. **** calculation
      of the amounts to be discounted, such final discount amount to be mutually
      agreed between the Parties.


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In
      the
      event Buyer elects not to exercise its option to take delivery at the
      Alternative Delivery Point, Seller shall still be obligated to deliver to Buyer
      the Nominated Volume.





**ARTICLE
      V**




**PRICING;
      INVOICING; PAYMENT TERMS**





**5.01**
            **Price
                of Product; Service Fees.******Product
                pricing shall be calculated monthly in accordance with the Propane
                and
                Butane content of the mix actually received by Buyer. Price shall
                be the
                sum of (i) the average price of Propane multiplied by its actual
                fraction
                and Butane multiplied by its actual fraction during the delivery
                Month as
                published by OPIS (Oil Price Information Service) for Mont Belvieu
                non-TET
                daily spot postings, and (ii) a premium (the "Service Fee") as provided
                in
                Exhibit B; it being understood that in no event shall the Butane
                component
                shall be greater than 10%.





**5.02**
            **Price
                of Additional Volume.******the
                Service Fee for additional volume, will be as provided in Exhibit
                B.





The
      estimated prices (the "Estimated Prices") to be used for interim invoicing
      purposes shall be determined in accordance with Sections 5.01 and 5.02
      (including the Service Fee), except that the price of Product shall be based
      on
      the closing posting price of the Mt. Belvieu non-TET as of the fifth Day prior
      to the delivery Month in which a posting price is published assuming ninety
      percent (90%) of Propane and ten percent (10%) normal Butane. At the end of
      the
      delivery Month, an adjustment shall be made *so* as
      to
      reflect the differences between the Estimated Prices as invoiced and the actual
      Month-end prices as determined in Sections 5.01 and 5.02 (the "True
      Up").





**5.03** **Invoicing.** **** Seller
      shall invoice and send Buyer every Friday, the total volume loaded during the
      immediately preceeding week, using the Estimated Prices (the "Estimated
      Invoices"), as set forth under Article 5.01.





The
      Month-End True Up shall be invoiced (the "True Up Invoice") at the end of the
      delivery Month. This True Up invoice shall include (i) the volume delivered
      from
      Seller to Buyer, and (ii) the realized price as per this Section. The True
      Up
      invoice must contain a deduction of US$8,500, representing Seller's payment
      of
      its share of Inspector's fees, as provided under Article 3.03.





All
      invoices shall comply with Buyer's treasury policies and shall be sent in
      original to Buyer's financial contact set forth in the notice provision of
      this **** Agreement.
      Neither faxed nor copied invoices will be acceptable to Buyer.


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**5.04**  **Payment
      Terms.** **** Except
      as
      otherwise agreed in this Agreement, payments shall be made by Buyer in net
      U.S.
      Dollars without set-off, deduction or counterclaim, and by wire transfer to
      Seller's designated account, as follows.





**5.04.1** **Estimated
      Invoices Payment.** **** Payment
      of each of the Estimated Invoices shall be made by Buyer ten (10) Days after
      the
      date on which such Estimated Invoices are received by Buyer. In case that
      payment date falls on a Sunday or holiday, then payment date will be the next
      Banking Day. In case that payment date falls on a Saturday, then payment date
      will be the prior Banking Day.





**5.04.2** **True
      Up Invoice Payment.** **** Payment
      of any amount due, either from Buyer to Seller or from Seller to Buyer shall
      be
      made in U.S. Dollars within ten (10) Days after receipt of the original invoice.
      In case that payment date falls on a Sunday or holiday, then payment date will
      be the next Banking Day. In case that payment date falls on a Saturday, then
      payment date will be the prior Banking Day.





**5.04.3** **Other
      Payments.** **** Except
      as
      provided in Articles 5.04.1 and 5.04.2 above, any amount due from one Party
      to
      the other shall be paid in U.S. Dollars within ten (10) Days after receipt
      of
      the original invoice. In case that payment date falls on a Sunday or holiday,
      then payment date will be the next Banking Day. In case that payment date falls
      on a Saturday, then payment date will be the prior Banking Day.





**5.04.4** **Office
      Expenses.** **** Seller
      shall provide Buyer with a list detailing certain expenses which Buyer shall
      be
      liable for and which may include telephone, telefax, cleaning and secretarial
      services, as well as expenses incurred by Buyer's Representatives supervising
      receipt of the Product deliveries at the Delivery Point. Buyer's Representatives
      must approve such detailed list. Seller shall invoice Buyer at the end of the
      Month U.S. $2,500 for such expenses, and Buyer shall pay Seller within twelve
      (12) Days after receipt of the original invoice at Buyer's offices. If payment
      date falls on a weekend or U.S. or Mexican holiday, payment shall be made on
      the
      following Banking Day. Extraordinary expenses shall be mutually agreed by the
      Parties.





**5.04.5** **Late
      payments.** If
      either
      Party does not make timely payments of any amount due under this Agreement,
      then
      any such late payment shall accrue interest at a rate equal to the Prime Rate
      announced by Citibank N.A., New York, New York, U.S., pro-rated for the number
      of days a payment is late. If either Party, for any reason, disputes an amount
      which is invoiced or claimed to be owed, then such Party shall promptly pay
      the
      undisputed amount to the extent that such amount is undisputed. **** Buyer
      and
      Seller shall resolve the disputed amount, and a replacement invoice shall be
      issued and payment of the replacement invoice shall be made in accordance with
      Section 5.03. The failure of a Party to object to an invoice within ten (10)
      Days after receipt of the invoice shall de deemed considered a waiver of such
      Party's right to contest the invoiced amount. If a timely objection is raised
      and not resolved within thirty (30) Days thereafter, the dispute may then be
      submitted to the American Arbitration Association through its expedited
      arbitration procedures.


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**ARTICLE
      VI**


**REPRESENTATIONS
      AND WARRANTIES**





Seller
      hereby represents and warrants to Buyer as follows:





**6.01** **Organization
      and Qualification.** **** Seller
      is
      a corporation duly organized, validly existing and in good standing under the
      laws of the jurisdiction of its incorporation and has all requisite corporate
      power and authority to own and operate its assets and properties and to carry
      on
      its business as currently conducted. Seller is duly qualified to do business
      and
      is in good standing as a foreign corporation in each jurisdiction where the
      ownership or operation of its assets and properties or the conduct of its
      business requires such qualification.





**6.02** **Corporate
      Authorization.** **** Seller
      has full corporate power and authority to execute and deliver this Agreement,
      and to perform its obligations hereunder. The execution, delivery, and
      performance by Seller of this Agreement have been duly and validly authorized
      and no additional corporate authorization or consent is required in connection
      with the execution, delivery and performance by it of this
      Agreement.





**6.03** **Consents
      and Approvals.** **** No
      consent, approval, waiver or authorization is required to be obtained by Seller
      from, and no notice or filing is required to be given by Seller or made by
      Seller with, any federal, state, local or foreign governmental authority or
      other person in connection with the execution, delivery and performance of
      this
      Agreement.





**6.04** **Non-Contravention.** **** The
      execution, delivery and performance by Seller of this Agreement, and the
      consummation of the transactions contemplated hereby, do not and will not (i)
      violate any provision of the organizational documents of Seller; (ii) conflict
      with, or result in the breach of, or constitute a default under, or result
      in
      the termination, cancellation or acceleration (whether after the filing of
      notice or the lapse of time or both) of any right or obligation of Seller under,
      or to a loss of any benefit to which Seller is entitled under, any contract;
      or
      (iii) or result in a breach of or constitute a default under any law of any
      court or governmental authority to which Seller is subject.


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**6.05** **Binding
      Effect.** **** This
      Agreement constitutes a valid and legally binding obligation of Seller
      enforceable against Seller in accordance with the terms of this Agreement,
      subject to bankruptcy, insolvency, reorganization, moratorium and similar laws
      of general applicability relating to or affecting creditors' rights and to
      general equity principles.





Buyer
      hereby represents and warrants to Seller as follows:





**6A.01** **Organization
      and Qualification.** **** Buyer
      is
      a corporation duly organized, validly existing and in good standing under the
      laws of the jurisdiction of its incorporation and has all requisite corporate
      power and authority to own and operate its assets and properties and to carry
      on
      its business as currently conducted. Buyer is duly qualified to do business
      and
      is in good standing as a foreign corporation in each jurisdiction where the
      ownership or operation of its assets and properties or the conduct of its
      business requires such qualification.





**6A.02** **Corporate
      Authorization.** Buyer
      has
      full corporate power and authority to execute and deliver this Agreement, and
      to
      perform its obligations hereunder. The execution, delivery and performance
      by
      Buyer of this Agreement have been duly and validly authorized and no additional
      corporate authorization or consent is required in connection with the execution,
      delivery and performance by it of this Agreement.





**6A.03** **Consents
      and Approvals.** **** No
      consent, approval, waiver or authorization is required to be obtained by Buyer
      from, and no notice or filing is required to be given by Buyer or made by Buyer
      with, any federal, state, local or foreign governmental authority or other
      person in connection with the execution, delivery and performance of this
      Agreement.





**6A.04** **Non-Contravention.** **** The
      execution, delivery and performance by Buyer of this Agreement, and the
      consummation of the transactions contemplated hereby, do not and will not (i)
      violate any provision of the organizational documents of Buyer; (ii) conflict
      with, or result in the breach of, or constitute a default under, or result
      in
      the termination, cancellation or acceleration (whether after the filing of
      notice or the lapse of time or both) of any right or obligation of Buyer under,
      or to a loss of any benefit to which Buyer is entitled under, any contract;
      or
      (iii) or result in a breach of or constitute a default under any law of any
      court or governmental authority to which Buyer is subject.





**6A.05** **Binding
      Effect.** **** This
      Agreement constitutes a valid and legally binding obligation of Buyer
      enforceable against Buyer in accordance with the terms of this Agreement,
      subject to bankruptcy, insolvency, reorganization moratorium and similar laws
      of
      general applicability relating to or affecting creditors' rights and to general
      equity principles.


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**ARTICLE
      VII**


**TERMINAL-RELATED
      PROVISIONS; REGULATORY COMPLIANCE**





**7.01** **Terminal
      Safety.** **** Buyer
      will comply, and will cause Buyer's Representatives entering into the Delivery
      Point (or the Alternative Delivery Point, if such is the case) to comply, with
      all applicable terminal safety and health regulations. Seller will furnish
      to
      Buyer prior to accepting any Product at the Delivery Point (or the Alternative
      Delivery Point, if such is the case), all information (including applicable
      material safety data sheets), documents, labels, placards, container, and other
      materials which are required to be furnished pursuant to statutes, ordinances,
      rules or regulations of any public authority relating to the describing,
      packaging, receiving, storing, handling, or shipping of Product at or from
      the
      Delivery Point (or the Alternative Delivery Point, if such is the case). Seller
      shall provide such information on the date of execution of this
      Agreement.





**7.02** **Loading.** **** Seller
      will provide loading services at the Delivery Point (or the Alternative Delivery
      Point, if such is the case) seven (7) Days a week, twenty-four (24) hours per
      Day. If the Parties determine that it is not necessary to have personnel 24
      hours a Day based upon operational experience developed on site, hours of
      service shall be subject to availability of Buyer's Representatives to dispatch
      Product from the Delivery Point (or the Alternative Delivery Point, if such
      is
      the case).





Seller
      will provide Buyer, in addition to the Inspector's report, with a daily activity
      report specifying the quantity (weight and volume) and quality of Product
      delivered to Buyer at the Delivery Point (or the Alternative Delivery Point,
      if
      such is the case).





**7.03** **Spill/Environmental
      Pollution.** **** If
      any
      Propane and/or Butane or Product spill or other environmental polluting
      discharge occurs in connection with or relating to any Product prior to delivery
      of such Product, all containment and clean-up operations (including those
      required by any governmental authority), shall be at Seller's
      expense.





If
      such
      spill or environmental polluting discharge occurs after delivery at the Delivery
      Point (or the Alternative Delivery Point, is such is the case), Buyer authorizes
      Seller to commence containment or clean-up operations as deemed appropriate
      or
      necessary by Seller or as may be required by any governmental authority. Seller
      will notify Buyer immediately of such operations. Seller shall have the right
      to
      direct all containment and clean-up operations.





All
      costs
      of containment and clean-up for any spill or environmental pollution will be
      borne by the Party responsible for such spill or environmental pollution, and
      such Party shall indemnify and hold harmless the other Party from any and all
      expenses, claims, liabilities, damages, penalties, fines and other costs
      (including, without limitation, attorneys' fees) resulting from or related
      to
      such incident.


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**7.04** **Terminal
      Regulatory Compliance.** **** Seller
      warrants that the terminals at the Delivery Point and the Alternative Delivery
      Point, respectively, comply, and covenants that such terminals will comply
      at
      all times during the Term of the Agreement, with all local, state and federal
      laws, rules or regulations applicable to terminals, including without
      limitation, all such laws, rules or regulations concerning permits and insurance
      required for owning, leasing, using, or operating a terminal at the Delivery
      Point or Alternative Delivery Point.





**ARTICLE
      VIII**


**CHANGE
      OF CIRCUMSTANCES**





In
      case
      of issuance of licenses by the Mexican government allowing private companies
      to
      import Product into Mexico, any party shall have the right to notify the other
      party its desire to reduce the quantity stated in this Agreement or its desire
      to terminate this Agreement in advance. The negotiation process shall last
      no
      more than thirty (30) Days. If, by the end of such period, the parties do not
      reach a mutual consent, this Agreement shall be deemed terminated





**ARTICLE
      IX**


**MISCELLANEOUS**





**9.01** **Notices.** **** All
      notices or other communications hereunder **** shall
      be
      deemed to have been duly given and made, if in writing and if served by personal
      delivery upon the Party for whom it is intended, if delivered by registered
      or
      certified mail, return receipt requested, or by a national courier service,
      or
      if sent by telecopier; provided that the telecopy is promptly confirmed by
      telephone confirmation thereof, to the person at the address set forth below,
      or
      such other address as may be designated in writing hereafter, in the same
      manner, by such person:





**BUYER:**
            **P.M.I.
                TRADING LIMITED**ADDRESS:****
            Av.
                Marina Nacional No. 329
              Torre
                Ejecutiva, Piso 20
              Col.
                Huasteca
              11311
                México D.F.****




Commercial
      Contact





Name:
            Rodrigo
                Aranda / Diana SalmónTelephone:
            (52-55)
                1944-0124/0158/0240 / (713) 567-0124/0158/0240Telex
                No.:****
            1773671Fax
                No.:
            (52-55)
                1944-0134 / (713) 567 0134


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  Operations
      Contact





Name:
            Cesar
                Covarrubias/Manuel Villarino/Salvador HuertasTelephone:
            (52-55)
                1944-0114/0142/0119 / (713) 567-0114/0142/0119Telex
                No.:****
            1773671/1773509Fax
                No.:
            (52-55)
                1944-0111 / (713) 567-0111





Financial
      Contact





Name:
            Juan
                Carlos Caballero/Francisco CervantesTelephone:
            (52-55)
                1944-0074/0077 / (713) 567-0074/0077Telex
                No.:
            1773671-1773509Fax
                No.:
            (52-55)
                1944-0072 / (713) 567-0072





**SELLER:**
            **RIO
                VISTA OPERATING PARTNERSHIP L.P.**ADDRESS:
            820
                Gessner Rd. Ste. 1285Houston,
                Texas, 77024





Commercial
                ContactsName:
            Charlie
                HandlyTelephone
                No.:
            (713)
                467-8235Fax
                No.:
            (713)
                467-8258Name:
            Vicente
                SorianoTelephone
                No.:
            (52-55)
                5661-9408Fax
                No.:
            (52-55)
                5661-2776Operations
                ContactName:
            Charlie
                HandlyTelephone
                No.:
            (713)
                467-8235Fax
                No.:
            (713)
                467-8258Name:
            Vicente
                SorianoTelephone
                No.:
            (52-55)
                5661-9408Fax
                No.:
            (52-55)
                5661-2776Name:
            Pedro
                PradoTelephone
                No.:
            (868)
                919-2364Fax
                No.:
            (868)
                819-2365Carretera
                La Rosita - Lucio Blanco KM. 34La
                Gloria, TamaulipasFinancial
                ContactName:
            Ian
                BothwellTelephone
                No.:
            (310)
                563-1830Fax
                No.:
            (310)
                563-6290


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**9.02** **Amendment;
      Waiver.** **** Any
      provision of this Agreement may be amended or waived if, and only if, such
      amendment or waiver is in writing and signed, in the case of an amendment,
      by
      Buyer and Seller, or in the case of a waiver, by the Party against whom the
      waiver is to be effective. In the event of any such attempted assignment or
      delegation by any Party without the consent of the other Party, such Party
      shall
      have the right, without prejudice to any other rights or remedies it may have
      hereunder or otherwise, to terminate the Agreement effective immediately upon
      notice to the other Party.





No
      failure or delay by any Party in exercising any right, power or privilege
      hereunder shall operate as a waiver thereof nor shall any single or partial
      exercise thereof preclude any other or further exercise thereof or the exercise
      of any other right, power or privilege. The rights and remedies herein provided
      shall be cumulative and not exclusive of any rights or remedies provided by
      law.





**9.03** **Assignment.** **** No
      Party
      to this Agreement may assign any of its rights or obligations under this
      Agreement without the prior written consent of the other Party hereto.
      Notwithstanding the foregoing, Buyer may freely assign the Agreement to any
      affiliate thereof and Seller will have the right to assign this Agreement if
      substantially all of its assets are sold or in the event a merger with another
      entity in which it is not the surviving entity, provided that Seller receives
      the prior written consent from Buyer.





**9.04** **Entire
      Agreement.** **** This
      Agreement (including
      all Exhibits hereto) contains the entire agreement between the Parties hereto
      with respect to the subject matter hereof and supersedes all prior agreements
      and understandings, oral or written, with respect to such matters.





**9.05** **Fulfillment
      of Obligations.** **** Any
      obligation of any Party to any other Party under this Agreement, which
      obligation is performed, satisfied or fulfilled by an Affiliate of such Party,
      shall be deemed to have been performed, satisfied or fulfilled by such
      Party.





**9.06** **Parties
      in Interest.** **** This
      Agreement shall inure to the benefit of and be binding upon the Parties hereto
      and their respective successors and permitted assigns. Nothing in this
      Agreement, express or implied, is intended to confer upon any Person other
      than
      Buyer, Seller or their respective successors or permitted assigns, any rights
      or
      remedies under or by reason of this Agreement.





**9.07** **Disclosure.** **** Notwithstanding
      anything herein to the contrary, each of the Parties hereby agrees with the
      other Party or Parties hereto that, except as may be required to comply with
      the
      requirements of any applicable Laws and the rules and regulations of any stock
      exchange upon which the securities of one of the Parties is listed, no press
      release or announcement or communication of any kind shall ever, whether prior
      to or subsequent to the **** execution
      of this Agreement, be made or caused to be made concerning the **** execution,
      performance or terms of this Agreement unless specifically approved in advance
      by all Parties hereto.


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          21


**9.08** **Expenses.** **** Except
      as
      otherwise expressly provided in this Agreement, whether or not the transactions
      contemplated by this Agreement are consummated, all costs and expenses incurred
      in connection with this Agreement and the transactions contemplated hereby
      shall
      be borne by the Party incurring such expenses.





**9.09** **Governing
      Law.** **** This
      agreement shall be governed by, and construed in accordance with the internal
      laws of the state of New York without regard to its conflicts of law
      principals.





**9.10** **Arbitration.** **** Any
      and
      all disputes, claims or controversies arising under or relating to this
      Agreement shall be settled by arbitration administered by the American
      Arbitration Association ("AAA") under its International Arbitration Rules.
      The
      place of the arbitration shall be New York City, New York, U.S. The Parties
      agree that the number of arbitrators shall be three. Each Party shall nominate
      a
      neutral and independent arbitrator, and the two arbitrators so appointed shall
      appoint the third neutral and independent arbitrator, who shall act as the
      Chairperson. If the arbitrators selected by the Parties are unable or fail
      to
      agree upon the third arbitrator, the third arbitrator shall be selected by
      the
      AAA. The award shall be in writing, shall be signed by a majority of the
      arbitrators, and shall include a statement regarding the reasons for the
      disposition of any claim. A judgment of the court having jurisdiction may be
      entered on the award. Except as may be required by law, neither a Party nor
      an
      arbitrator may disclose the existence, content, or results of any arbitration
      hereunder without the prior written consent of both Parties.





**9.11** **Counterparts.** **** This
      Agreement may be executed in one or more counterparts, each of which shall
      be
      deemed an original, and all of which shall constitute one and the same
      Agreement.





**9.12** **Headings.** **** The
      heading references herein and the table of contents hereto are for convenience
      purposes only, do not constitute a part of this Agreement and shall not be
      deemed to limit or affect any of the provisions hereof.





**9.13** **Severability.** **** The
      provisions of this Agreement shall be deemed severable and the invalidity or
      unenforceability of any provision shall not affect the validity or
      enforceability of the other provisions hereof. If any provision of this
      Agreement, or the application thereof to any Person or any circumstance, is
      invalid or unenforceable, (a) a suitable and equitable provision shall be
      substituted therefore in order to carry out, so far as may be valid and
      enforceable, the intent and purpose of such invalid or unenforceable provision
      and (b) the remainder of this Agreement and the application of such provision
      to
      other Persons or circumstances shall not be affected by such invalidity or
      unenforceability, nor shall such invalidity or unenforceability affect the
      validity, or enforceability of such provision, or the application thereof,
      in
      any other jurisdiction.


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**9.14** **Third
      Party Beneficiaries.** **** Nothing
      in the Agreement is intended or shall be construed to confer upon or give to
      any
      Person or entity any rights as a third party beneficiary of the Agreement or
      any
      part thereof.





**9.15** **Taxes
      and Documents.** **** Each
      Party shall be responsible for paying any taxes, duties, fees or whichever
      other
      similar to which they are obliged to pay in accordance with the applicable
      law.





Seller
      will be obliged to provide Buyer with a valid North American Free Trade
      Agreement certificate of origin. If for any reason Seller does not provide
      Buyer
      with such certificate of origin, Buyer shall have the right to discount from
      the
      final purchase price of Product, any and all taxes, duties or fees imposed
      by
      the Mexican governmental authorities which must be paid in excess by Buyer,
      due
      to the lack of the above-mentioned certificate.





**9.16** **Other
      Terms and Conditions.** **** Except
      as
      would conflict or except as otherwise provided in this Agreement, Incoterms
      2000
      for DDU or FCA, as appropriate, shall apply. In no event shall the United
      Nations Convention for the International Sales of Goods apply to this
      Agreement.





**9.17** **Force
      Majeure.** **** Neither
      Party shall be liable for losses, damages, claims or demands of any nature
      arising out of delays or defaults in performance under the Agreement due to
      any
      unforeseeable impediment beyond the reasonable control of the Parties ("Force
      Majeure"), which shall include, but not be limited to: acts of god or public
      enemy; floods or fire; hostilities or war (whether declared or undeclared);
      blockades; labor disturbances, strikes, riots, insurrections or civil commotion;
      quarantine restrictions or epidemics; electrical shortages or blackouts;
      earthquakes; tides, storms or bad weather; accidents; breakdown or injury to
      Buyer's (or Seller's) facilities; or laws, decrees, regulations, orders or
      other
      directives or actions of either general or particular application of the
      government of México or the U. S. or any agency thereof or of a person or
      authority purporting to act therefore, or request of any such person or
      authority. Any Party claiming Force Majeure shall promptly notify the other
      of
      the occurrence of the event of Force Majeure relied upon and shall estimate
      the
      length of time that the Force Majeure condition is expected to continue. Such
      Party shall also promptly notify the other Party of the cessation of the Force
      Majeure condition. Nothing in this Article shall relieve Buyer of its obligation
      to pay in full for product sold and effectively delivered and to pay all other
      amounts due to Seller under the Agreement.





The
      occurrence of an event of Force Majeure shall not operate to extend the period
      of this Agreement. Should any such event curtail or suspend the performance
      of
      either Party hereunder for a period in excess of seven (7) Days, either Party
      shall have the right to terminate this Agreement upon notice to the other
      Party.





If,
      as a
      result of Force Majeure, Seller at any time does not have available a sufficient
      amount of Product to be sold to Buyer, Seller shall be **** obligated
      to equally prorate the available amount it holds for export among its customers,
      including Buyer, or shall make reasonable commercial efforts to purchase Product
      from any third party to sell to Buyer.


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**9.18** **Confidentiality.** **** The
      Parties agree to keep all terms and conditions of this Agreement, including
      the
      Parties' identities, private and confidential except to the extent that
      disclosure is required under any rule or regulation to which the Party shall
      be
      subject. This obligation shall be of a continuing nature and shall not be
      canceled by the termination of this Agreement.





**9.19** **Limitation
      of Liability.** **** Neither
      Party shall be liable for special, indirect, incidental or consequential damages
      of any kind arising out of or in any way connected with the performance of
      or
      failure to perform this Agreement.





**9.20** **Indemnity.** **** Seller
      agrees to indemnify, defend and fully hold harmless Buyer and/or any of its
      officers, directors, representatives, employees, shareholders, subsidiaries,
      agents, invitees, or licensees thereof, from and against any and all claims,
      liabilities, damages, losses, costs, expenses (including reasonable attorney's
      fees) demands, fines, suits, causes of action or judgments, directly or
      indirectly, arising out of, in connection with, or resulting from, Product
      related incident causing property damage, personal injury or death, whether
      or
      not claimants allege Seller's negligence as a cause, while Seller has custody
      of
      Product.





Likewise,
      Seller shall indemnify, defend and hold harmless Buyer from and against all
      actual or alleged liability, loss, or damage to Buyer or third parties resulting
      from Seller's breach of this Agreement.





**ARTICLE
      X**


**TERMINATION**





**Termination
      for Various Events.** **** Notwithstanding
      anything herein to the contrary, either Party may (in addition to any other
      rights or remedies provided to the other Party under this Agreement) terminate
      this Agreement, effective immediately upon notice to the other Party, if any
      of
      the following events occurs, and no alternative payment arrangement has been
      made to secure payment to the terminating Party:





(a)
            The
                other Party (or any guarantor of the other Party's obligations hereunder)
                institutes proceeding to be adjudged bankrupt or insolvent, seeks
                or
                suffers reorganization under court order, seeks the benefit of any
                law for
                the relief of debtors, makes an assignment for the benefit of creditors,
                admits in writing its inability to pay its debts generally, when
                become
                due, or performs any other generally recognized act of insolvency
                or
                bankruptcy, or there shall be declared a****moratorium
                on the payment of the other Party's (or such guarantor's)
                debts;


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(b)
            There
                is entered any decree or order by a court adjudging the other Party
                (or
                any guarantor of any of the other Party's obligations hereunder)
                bankrupt
                or insolvent, approving a petition for reorganization, approving
                a
                petition seeking the benefit of any law for the relief of debtors,
                appointing a receiver, or decreeing or ordering the winding-up or
                liquidation of the other Party's (or such guarantor's)
                affairs;





(c)
            Any
                law, rule, regulation or decree of any competent authority restricts
                the
                ability of the other Party (or any guarantor of any of the other
                Party's
                obligations hereunder) to obtain U.S. Dollars for payments to be
                made
                under the Agreement (or any guaranty);
                and





(d)
            Any
                material representation or material warranty made by the other Party
                (or
                any guarantor of any of the other Party's obligations hereunder)
                hereunder
                or otherwise proves to be false or incorrect in any material
                respect.





In
      witness whereof, the parties have duly executed this agreement as of day first
      above written.





**Rio
                Vista Operating Partnership L.P.**
            
            **P.M.I.
                Trading Limited**/s/
                Charles C. Handly
            
            /s/
                Rodrigo Aranda**Charles
                C. Handly**
            
            **Rodrigo
                Aranda**Title:
            
            Title:President
            
            Signatory





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