Exhibit 10.4

                                                                   TRD-DP-052/05
                                                                     DTIR-05-018



                 MATAMOROS LPG MIX PURCHASE AND SALES AGREEMENT



                                     BETWEEN



          RIO VISTA ENERGY PARTNERS 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  June  4th, 2005, by and between Rio Vista Energy Partners
L.P.,  a  corporation  organized under the laws of the State of Delaware, United
States  of  America, having its principle 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 herby 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 Petroquimica Basica'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;


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     "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;

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

     "Exhibit  A"  contains  the  Product  specifications;

     "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 Farenheit (60 degrees F);

     "GPA"  shall  mean  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  Petroquimica  Basica;

     "Products"  shall mean Product, Butane or Propane, as the context dictates;

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

     "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 of from Seller, Products
in  such volumes as specified in, and otherwise 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 June 4th, 2005 (the
"Effective  Date")  and  end  on  March  31st,  2006.


                                   ARTICLE III

                                     PRODUCT

     3.01     PRODUCT SPECIFICATIONS. Products  shall,  at  all  times  meet the
              ----------------------
specification  parameters  set  forth  in  Exhibit  A.
                                           ----------

     3.02     PRODUCT QUANTITY. In accordance with the following table:
              ----------------

<TABLE>
<CAPTION>
<S>                            <C>
------------------------------------------------------------------
3.5 MMgal per Month            FROM JUNE 1st, 2005 (1) THROUGH
                               AUGUST 31st, 2005
------------------------------------------------------------------
6.0 MMgal per Month            FROM SEPTEMBER 1st THROUGH
+/- 5% at Buyer's option       SEPTEMBER 30th, 2005.
------------------------------------------------------------------
9.0 MMgal per Month            FROM OCTOBER 1st THROUGH
+/- 10% at Buyer's option      OCTOBER 31st, 2005.
------------------------------------------------------------------
13.0 MMgal per Month           FROM NOVEMBER 1st, 2005 THROUGH
+/- 10% at Buyer's option      FEBRUARY 28th, 2006.
------------------------------------------------------------------
9.0 MMgal per Month            FROM MARCH 1st THROUGH
+/- 10% at Buyer's option      MARCH 31st, 2006.
------------------------------------------------------------------
</TABLE>

1)  Monthly  volume  for June 2005, shall be prorated during the delivery period
(June 4th through June 30th, 2005) on the basis of 3,500,000 Gallons of LPG Mix.

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  the  Article  3.02.


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     3.03     BUYER'S  SHORTFALL.
              ------------------

          3.03.1     SHORTFALL  OCCURRENCE.  A  shortfall  attributable to Buyer
                     ---------------------
(the  "Buyer's  Shortfall")  shall  occur  when  the  volume of Product actually
delivered  by  Seller  and  lifted  by Buyer during any Month of the Term at the
Delivery  Point (or Alternative Delivery Point, if Buyer exercises its option to
take  delivery  at the Alternative Delivery Point) (the "Actual Volume") is less
than the Nominated Volume, provided, however, that a Buyer's Shortfall shall not
be  deemed  to  have  occurred  in the event Buyer fails to take delivery of the
Nominated  Volume  due  to Seller's fault or non-compliance with this Agreement,
including  without limitation, Seller's failure to deliver the Nominated Volume,
the provision of non-compliant Product, or Seller's inability to deliver Product
to  the  Delivery  Point  (or Alternative Delivery Point, if Buyer exercises its
option to take delivery at the Alternative Delivery Point), and any such volumes
not  delivered  by  Seller  shall be deducted from the Shortfall Computation, as
defined  below.

          3.03.2     SHORTFALL  COMPUTATION.  A  Buyer's  Shortfall shall be the
                     ----------------------
positive  difference  between  the  Nominated  Volume and the Actual Volume (the
"Buyer's  Shortfall  Volume"), provided, however, that should Buyer fail to take
delivery  of  the  Nominated  Volume  during  the  Term due to Seller's fault or
non-compliance  with  the  Agreement,  including  without  limitation,  Seller's
failure to deliver the Nominated Volume, the provision of non-compliant Product,
or  Seller's  inability to deliver Product to the Delivery Point (or Alternative
Delivery  Point,  if  Buyer  exercises  its  option  to  take  delivery  at  the
Alternative  Delivery  Point), then the Nominated Volume shall be reduced by the
amount  of  Product  not  delivered  by  Seller.

          3.03.3     SHORTFALL  POTENTIAL COMPENSATION. If a  Buyer's  Shortfall
                     ----------------------------------
occurs,  Buyer  shall make its best efforts with no obligation or whatsoever, to
receive  the Buyer's Shortfall Volume during one or more of the following Months
on  the  basis  of  Article  3.02.

     3.04     PRODUCT  QUALITY  AND QUANTITY INSPECTIONS. Buyer and Seller shall
              ------------------------------------------
appoint  and  independent  inspection  company  mutually  agreeable to Buyer and
Seller (the "Inspector") 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 gross 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.

          3.04.1     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 Injection Point for 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


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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 nor for
any  Shortfall  Payment.  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.

          3.04.2     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 degrees F in accordance with the Compliance Procedures, through
the  determination of the specific gravity through gas chromatograph provided by
Seller  or  by Inspector. The Inspector shall take samples at the Delivery Point
(at the Micromotion measurement device installed at the connection point between
Seller's  pipeline  and  the Delivery Pont) for every 50,000 Gallons received at
the  Delivery  Point.  The  gas  chromatograph  utilized  shall be calibrated in
accordance  with  the  latest  ASTM  and  GPA  procedures.

     (b)  Seller's  terminal  platform  scale at the Delivery Point/ Alternative
Delivery  Point  will  be  tested and adjusted for accuracy and least once every
sixty  (60)  Days.  Seller  will  be required to comply with the calibration and
certification  procedures  adopted  by  Mexican  authorities  in accordance with
Official  Standards  (NOM-010-SCFI-1994  (1999)).  Buyer's  Representative  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.

     (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.


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     (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 expenses associated
with  such  new  scales.

     (e)  For  customers  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  degrees 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 every 50,000 Gallons received at the Delivery Point,
through  GC.

     Additionally, for verification and customs purposes, Product pumped through
Seller's  pipeline  form  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 degrees 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 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.

     3.05     SELLER'S  FAILURE TO DELIVER NOMINATED VOLUME. In the event Seller
              ---------------------------------------------
fails  to  delivery the Nominated Volume by Buyer in the accordance with Article
3.02  of  this  Agreement  ("Seller's Shortfall"), then Seller agrees that Buyer
shall  be  entitled  to  purchase  substitute  product in an amount equal to the
difference  between  the  Nominated  Volume  and  the Actual Volume delivered by
Seller  ("Seller's  Shortfall  Volume").  The  aforementioned,  however,
notwithstanding Buyer's right to exercise any right or remedy provided under the
Agreement  or  otherwise.


                                   ARTICLE IV

                  PRODUCT DELIVERY; TRANSFER OF TITLE; CUSTODY


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                         RISK OF LOSS AND CONTAMINATION

     4.01     PRODUCT  DELIVERED  AT  DELIVERY POINT. Product shall be delivered
              ---------------------------------------
DDU  at  the  scale exit of the Delivery Point. Title of Product shall pass from
Seller  to Buyer at the point in the Seller's pipeline where Product passes into
Mexico  at the U.S./Mexico border in Matamoros, Tamaulipas, Mexico. The custody,
risk of loss and contamination with respect to Product shall pass from Seller to
Buyer  at  the  scale  exit  of  the  Delivery  Point.

     4.02     PRODUCT DELIVERED AT THE ALTERNATIVE DELIVERY POINT. If, by reason
              ----------------------------------------------------
of  a  programmed  maintenance  or  an event different from Force Majeure at the
Delivery  Point,  Seller  is  not able to deliver Product at the Delivery Point,
Buyer  shall  have  the  option  of  loading Product at the Alternative Delivery
Point,  in which case Buyer shall so notify to Seller. The Product shall be then
delivered  FCA  at  the  scale  exit of the Alternative Delivery Point. Title of
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.
Custody,  risk of loss and contamination with respect to Product shall pass from
Seller  to  Buyer  at  the  scale  exit  of  the  Alternative  Delivery  Point.

For  Product  delivered  at the Alternative Delivery Point, Buyer shall nominate
tank  truck  transportation  services.  Seller  shall  discount the Service Fee,
described  in  Article  5.01,  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, 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.

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  volume  nominated  by  Buyer  in  accordance with Section 3.02 and shall be
liable  for  any  Seller's  Shortfall,  in  accordance  with  Section  3.05.

                                    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


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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")  of U.S. XXX per Gallon of Product delivered during the Term; it
being  understood  that  in  no event the Butane component shall be greater than
10%.

The  estimated  prices (the "Estimated Prices") to be used for interim invoicing
purposes  shall be determined in accordance with the foregoing paragraph of this
Section 5.01 (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  computed  in  the  foregoing  paragraph  (the  "Month-End True Up").

     5.02     INVOICING.  Seller  shall invoice and send Buyer every Friday, the
              ----------
total  volume loaded during the immediately proceeding 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  the Seller to Buyer, and (ii) the realized price as per Section
5.01.  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
3.04.

     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.

     5.03     PAYMENT TERMS. 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.

          5.03.1     ESTIMATED  INVOICES  PAYMENT.  Payment  of  each  of  the
                     -----------------------------
Estimated  invoices  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,
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.

          5.03.2     TRUE  UP INVOICE PAYMENT. Payment of any amount due, either
                     -------------------------
from  Buyer  to  Seller  of  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


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Banking  Day.  In  case that payment date falls on a Saturday, then payment date
will  be  the  prior  Banking  Day.

          5.03.3     OTHER  PAYMENTS.  Except  as  provided  in Articles 5.03.1,
                     ----------------
5.03.2  above,  and 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.

          5.03.4     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.

          5.03.5     LATE PAYMENTS. If either Party does not make timely payment
                     --------------
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 Article 5.03. The failure of a Party to
object  to  an  invoice  within ten (10) Days after receipt of the invoice shall
terminate  the Party's right to contest the amount stated. 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 expected
arbitration  procedures.

                                   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


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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
has  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.

     6.05     BLINDING  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
has  been  duly and validly authorized and no additional corporate authorization
or  consent  is  required  in  connection  with  the  execution,  delivery  and
performance  by  it  or  this  Agreement.


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     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 and 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,  and contract; or (iii) or results 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.

                                   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  execute on its name, pay for, and 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  may  be  required  to  be  furnished  by  Buyer  by  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 at the 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).


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     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 environment 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 of 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.

     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 CIRUMSTANCES
                             ----------------------

The  deregulation  of  the  Mexican  LPG  market  shall  constitute  a Change of
Circumstance  under  this  Agreement. In case of any change in the regulation of
the  LPG Market in Mexico that allows free importation to private companies, 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 that thirty (30) Days. If,
by  the  end  of  such  period  the  parties do not reach a mutual consent, this
Agreement  shall  be  deemed  as  terminated.


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                                   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 Mexico D.F.

Commercial Contact

Name:                  Rodrigo Aranda / Adalberto Santin / Diana Salmon
Telephone:             (52-55) 1944-0124/0158/0240/ (713) 567-0124/0158/0240
Telex No.:             1773671
Fax No.:               (52-55) 1944-0134 / (713) 567-0134

Operations Contact

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

Financial Contact

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

SELLER:                RIO VISTA ENERGY PARTNERS L.P.
ADDRESS:               820 Gessner Rd. Ste. 1285
                       Houston, Texas, 77024

Commercial Contacts

Name:                 Richard Shore


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Telephone No.:        (925) 932-9270
Fax No.:              (925) 944-3339

Name:                 Charlie Handly
Telephone No.:        (713) 467-8235
Fax No.:              (713) 467-8258

Name:                 Vincente Soriano
Telephone No.:        (52-55) 5661-9408
Fax No.:              (52-55) 5661-2776

Operations Contact

Name:                 Charlie Handly
Telephone No.:        (713) 467-8235
Fax No.:              (713) 467-8258

Name:                 Vincente Soriano
Telephone No.:        (52-55) 5661-9408
Fax No.:              (52-55) 5661-2776

Name:                 Pedro Prado
Telephone No.:        (868) 919-2364
Fax No.:              (868) 819 2365
                      Carretera La Rosita - Lucio Blanco KM. 3.4
                      La Gloria, Tamaulipas

Financial Contact

Name:                 Ian Bothwell
Telephone No.:        (310) 563-1830
Fax No.:              (310) 563-6290

     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.


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     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,  which  consent  shall  not be unreasonably withheld.

     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.

     9.8     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


                                    16 of 21
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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
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.

     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.  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.

     9.16     OTHER  TERMS AND CONDITIONS. Except as would conflict or except as
              ----------------------------
otherwise  provided  in  this  Agreement,  Incoterms  2000 for DDU and FCA 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 demurrage,
              ---------------
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  of  war  (whether  declared  or  undeclared);  blockades;  labor
disturbances;  strikes;  riots;  insurrections  or  civil  commotion; quarantine
restrictions  or  epidemics;  electrical  shortages  or  blackouts; earthquakes;
tides,


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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 Mexico 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 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.

     9.18     CONFIDENTIALITY.  The  Parties  agree  to  keep  all  terms  and
              ----------------
conditions  of this Agreement private and confidential except to the extent that
disclosure  is required under any rule or regulation to which the Party shall be
subject.

     9.19     LIMITATION  OF  LIABILITY.  Neither  Party  shall  be  liable  for
              --------------------------
special,  indirect,  incidental  or  consequential  damages.

     9.20     APPLICABILITY  OF  SECTIONS  362(B)(6)  AND  556.  The  Parties
acknowledge  and agree that this Agreement is subject to Buyer's rights under 11
U.S.C.  Sec.Sec. 362 (b)(6) and 556. In that regard, the Parties acknowledge and
agree  that:

     (a)  The  Product  is  a  "commodity"  within the definition set forth in 7
U.S.C.  Sec. 1(a)(4) and 11 U.S.C. Sec. 761(8), and is the subject of dealing in
the  forward  contract  trade.

     (b)  This Agreement is a "forward contract" within the definition set forth
in  11  U.S.C.  Sec.  101(25) for the purchase, sale or transfer of a commodity.

     (c)  This  Agreement  has  a maturity date of more than two Days after this
Agreement  is  entered  into.

     (d)  Buyer  and  Seller  are  each a "forward contract merchant" within the
definition  set  forth  in  11  U.S.C.  Sec.  101(26).


                                    18 of 21
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     (e)  The contractual termination rights set forth in Sections 10(a) and (b)
hereof  are  conditions  of  the  kind  specified  in  11 U.S.C. Sec. 365(e)(1).

     (f)  The Parties therefore acknowledge and agree that this Agreement may be
terminated  by Buyer, in accordance with Sections 10(a) and (b) hereof, upon the
commencement  of  a  bankruptcy  case  or  insolvency proceeding by, or against,
Seller  under  and  Chapter  of  Title 11 of the United States Code or any other
applicable  insolvency,  or  similar,  law.

                                    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;

     (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  patition 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.


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     (e)  Buyer  recognizes  that  Seller  has  entered  into  negotiations  to
          evaluate the sale of substantially all of it assets. Such negotiations
          include  the  assignment  of  Seller's  long  term  supply  agreements
          involving  the  sale  and  delivery  of  LPG  to Seller's terminals in
          Matamoros,  Mexico  and  or  Brownsville, that Buyer shall have at all
          times the right to terminate this Agreement in its sole discretion, if
          Buyer  considers  that  the  assignment  of the Agreement to the asset
          purchaser  would materially affect reliable supply of LPG to Buyer, or
          if  such  attempted assignment or delegation by Seller is done without
          Buyer's prior written consent. In such event, Buyer shall further have
          the  right to exercise any rights or remedies it may have hereunder or
          otherwise.

In  witness  whereof,  the  parties have duly executed this agreement as of June
4th,  2005.

RIO VISTA ENERGY PARTNERS L.P.          P.M.I. TRADING LIMITED

/s/ Charles C. Handly                   /s/ Rodrigo Aranda
-------------------------               ---------------------

CHARLES C. HANDLY                       RODRIGO ARANDA

Title:                                  Title:
     President                               Signatory
-------------------------               ---------------------



                                  EXHIBIT "A"
                                  -----------


                                    20 of 21
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<TABLE>
<CAPTION>
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                                   Exhibit "A"
                                   -----------
                             PRODUCT SPECIFICATIONS

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TEST/                    SPECIFICATION             UNITS            METHOD
-----                    -------------             -----            ------
COMPONENT
---------
------------------------------------------------------------------------------
<S>                      <C>                       <C>              <C>
PROPANE                      90 MIN                 %VOL            GC (ASTM
                                                                    D 2163-
                                                                    91)
------------------------------------------------------------------------------
BUTANE                       10 MAX                 %VOL            GC (ASTM
                                                                    D-2163-
                                                                    91)
------------------------------------------------------------------------------
ETHANE                        2 MAX                 %VOL            GC (ASTM
                                                                    D-2163-
                                                                    91)
------------------------------------------------------------------------------
BUTYLENE                      1 MAX                 %VOL            GC (ASTM D
                                                                   -2163-91)
------------------------------------------------------------------------------
PROPYLENE                     2 MAX                 %VOL            GC (ASTM
                                                                    D-2163-
                                                                    91)
------------------------------------------------------------------------------
PENTANES &                    2 MAX                 %VOL            GC (ASTM
HEAVIES                                                             D-2163-
                                                                    91)
------------------------------------------------------------------------------
VAPOR                        200 MAX                PSIG            ASTM D-
PRESSURE                                                            1267-95
AT 100 F DEG.                                                       OR
                                                                    GC (ASTM
                                                                    D-2163-
                                                                    91)
------------------------------------------------------------------------------
SPECIFIC                        -                                   ASTM D-
GRAVITY                                                             1657 OR
                                                                    GC (ASTM
                                                                    D-2163-
                                                                    91)
                                                                    ASTM D-
                                                                    2598-96
------------------------------------------------------------------------------
CORROSION                       1                                   ASTM D-
COPPER STRIP                                                        1838-91
AT 100 F DEG.
------------------------------------------------------------------------------
OTHER                         NONE
DELETERIOUS
SUBSTANCES
------------------------------------------------------------------------------
ODORIZATION                 PRODUCT
                            SHALL BE
                            ODORIZED
                           (STENCHED)
                             AS PER
                          OFFICIAL U.S.
                           AND MEXICAN
                           REGULATIONS
------------------------------------------------------------------------------
</TABLE>
     Notes:    GC: Gas chromatograph
               Propane content; propane + ethane + propylene
               Butane content: normal butane + butylenes + pentane and heavies
               Determination of quality shall follow the latest revision of ASTM
               procedure.


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