OMNIBUS AGREEMENT


                                     BETWEEN


                            PENN OCTANE CORPORATION,

                                RIO VISTA GP LLC,


                         RIO VISTA ENERGY PARTNERS L.P.


                                       AND


                      RIO VISTA OPERATING PARTNERSHIP L.P.



                                OMNIBUS AGREEMENT

     THIS  OMNIBUS  AGREEMENT  is  entered  into as of September 16, 2004 by and
among  Penn  Octane  Corporation,  a Delaware corporation ("POCC"), Rio Vista GP
LLC,  a  Delaware  limited  liability company (the "General Partner"), Rio Vista
Energy  Partners  L.P.,  a Delaware limited partnership (the "Partnership"), and
Rio  Vista  Operating  Partnership  L.P.  (the  "Operating  Partnership").  The
above-named  entities  are  sometimes  referred  to  in this Agreement each as a
"Party"  and  collectively  as  the  "Parties."

                                    RECITALS:

     WHEREAS,  POCC  and  its  Affiliates  (as  defined  herein)  formed  the
Partnership,  the  General Partner and the Operating Partnership for the purpose
of  conducting  of  the  Business  (as  defined  below);

     WHEREAS,  certain assets and services used by POCC or its Affiliates in the
conduct  of  the  Business  prior  to  the formation of the Partnership were not
transferred  to  the  Partnership;

     WHEREAS,  the Parties desire to ensure the continued effective operation of
the  Business,  and the Parties recognize that the continued effective operation
of  the  Business  requires  that  POCC  provide certain management and employee
services  to  the  Business  as  set  forth  in  this  Agreement;  and

     WHEREAS, the Parties desire to evidence other agreements and relationships,
as  more  fully  set  out in this Agreement, with respect to the transfer of the
Business  to  the  Partnership  and  the  Operating  Partnership  as well as the
operation  of  the  Business  by  the Partnership and the Operating Partnership.

     NOW  THEREFORE,  in  consideration  of  the  premises  and  the  covenants,
conditions,  and  agreements  contained  herein, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
Parties  hereto  hereby  agree  as  follows:

                                    ARTICLE I

                                   DEFINITIONS

     DEFINITIONS.  (a) As used in this Agreement, the following terms shall have
the  respective  meanings  set  forth  below:

     "Affiliate"  means,  with  respect  to  any  Person,  any other Person that
directly  or  indirectly  through  one  or  more  intermediaries  controls,  is
controlled  by  or is under common control with, the Person in question. As used
herein,  the  term  "control"  means  the possession, direct or indirect, of the
power  to  direct  or  cause  the  direction of the management and policies of a
Person,  whether  through  ownership  of  voting  securities,  by  contract  or
otherwise.


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     "Agreement"  means  this Omnibus Agreement, as it may be amended, modified,
or  supplemented  from  time  to  time  in  accordance  with Section 4.7 hereof.

     "Assets"  means  the  "Contributed  Assets"  as such term is defined in the
Contribution  Agreement.

     "Business"  means  (i)  providing  transportation,  terminalling  and
distribution  services  for  hydrocarbon  products  and  by-products,  and  (ii)
marketing  and  selling  hydrocarbon  products  and  by-products.

     "Closing  Date"  means  the  date  of  the  Distribution.

     "Conflicts  Committee"  is  defined  in  the  Partnership  Agreement.

     "control"  means  the  possession,  directly or indirectly, of the power to
direct  or  cause  the  direction  of  the  management and policies of a Person,
whether  through  ownership  of  voting  securities,  by  contract or otherwise.

     "Contribution  Agreement" means the Contribution, Conveyance and Assumption
Agreement,  dated  September  16,  2004, by and among various POCC Entities, the
Partnership,  the  Operating  Partnership,  the  General  Partner  and Rio Vista
Operating  GP  LLC,  a  Delaware  limited  liability  company.

     "Covered  Environmental  Losses"  is  defined  in  Section  2.1(a).

     "Distribution" means the distribution by POCC of all the outstanding common
units  of  the  Partnership  representing  limited  partner  interests  to  the
stockholders  of  POCC.

     "Environmental  Laws"  means  all federal, state, and local laws, statutes,
rules, regulations, orders, and ordinances, now or hereafter in effect, relating
to protection of human health and the environment including, without limitation,
the  federal  Comprehensive  Environmental Response, Compensation, and Liability
Act, the Superfund Amendments Reauthorization Act, the Resource Conservation and
Recovery  Act,  the  Clean Air Act, the Federal Water Pollution Control Act, the
Toxic  Substances  Control  Act,  the Oil Pollution Act, the Safe Drinking Water
Act,  the  Hazardous  Materials  Transportation  Act,  and  other  environmental
conservation  and  protection  laws,  each  as  amended  from  time  to  time.

     "General  Partner"  is  defined  in  the  introduction  to  this Agreement.

     "Hazardous  Substance"  means any substance that is designated, defined, or
classified  as a hazardous waste, hazardous material, pollutant, contaminant, or
toxic  or  hazardous  substance,  or  that  is  otherwise  regulated  under  any
Environmental  Law,  including,  without  limitation, any hazardous substance as
defined  under  the  Comprehensive  Environmental  Response,  Compensation,  and
Liability  Act.


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     "Indemnified Party" means the Partnership Entities or the POCC Entities, as
the case may be, in their capacity as the parties entitled to indemnification in
accordance  with  Article  II.

     "Indemnifying  Party"  means  either  the  Partnership Entities or the POCC
Entities,  as  the  case  may  be,  in  its  capacity  as  the parties from whom
indemnification  may  be  sought  in  accordance  with  Article  II.

     "Losses" means any losses, damages, liabilities, claims, demands, causes of
action,  judgments,  settlements,  fines,  penalties,  costs,  and  expenses
(including,  without  limitation,  court  costs  and  reasonable  attorney's and
expert's  fees)  of  any  and  every  kind  or  character.

     "POCC"  is  defined  in  the  introduction  to  this  Agreement.

     "POCC  Entities"  means  POCC  and each of its Subsidiaries (other than the
General  Partner,  the  Partnership  and  any  Subsidiary  of  the Partnership).

     "Partnership"  is  defined  in  the  introduction  to  this  Agreement.

     "Partnership  Agreement"  means the First Amended and Restated Agreement of
Limited  Partnership  of  Rio  Vista  Energy  Partners  L.P.  No  amendment  or
modification  to  the Partnership Agreement subsequent to the Closing Date shall
be  given  effect for the purposes of this Agreement unless consented to by each
of  the  Parties  to  this  Agreement.

     "Partnership  Entities" means the Partnership, the General Partner and each
Subsidiary  of  the  Partnership.

     "Party"  and  "Parties"  is  defined in the introduction to this Agreement.

     "Pass-Through  Environmental  Losses"  is  defined  in  Section  2.1(b).

     "Person"  means  an individual or a corporation, limited liability company,
partnership,  joint  venture,  trust,  unincorporated organization, association,
government  agency  or  political  subdivision  thereof  or  other  entity.

     "Retained  Assets" means, collectively, any assets and investments owned by
any  of  the  POCC  Group  that  were  not  conveyed,  contributed  or otherwise
transferred  to any of the Partnership Entities prior to or on the Closing Date.

     "Services"  is  defined  in  Section  3.1.

     "Subsidiary"  means, with respect to any Person, (a) a corporation of which
more  than 50% of the voting power is owned, directly or indirectly, at the date
of  determination, by such Person, by one or more Subsidiaries of such Person or
a  combination  thereof, (b) a partnership (whether general or limited) in which
such  Person  or a Subsidiary of such Person is, at the date of determination, a
general or limited partner of such partnership, but only if more than 50% of the
partnership  interests  of  such partnership (considering all of the partnership
interests  of  the


                                        4

partnership  as a single class) is owned, directly or indirectly, at the date of
determination,  by such Person, by one or more Subsidiaries of such Person, or a
combination  thereof,  or  (c)  any  other Person (other than a corporation or a
partnership) in which such Person, one or more Subsidiaries of such Person, or a
combination  thereof,  directly or indirectly, at the date of determination, has
(i)  at least a majority ownership interest or (ii) the power to elect or direct
the  election  of  a  majority  of the directors or other governing body of such
Person.

                                   ARTICLE II

                                 INDEMNIFICATION

     2.1  ENVIRONMENTAL  INDEMNIFICATION.

          (a)  Subject to the limitations contained in this Section 2.1(a), POCC
shall  indemnify, defend and hold harmless each of the Partnership Entities from
and  against  environmental  and toxic tort Losses suffered, incurred or paid by
any  of  the  Partnership  Entities  by  reason  of  or  arising  out  of:

               (i)  any  violation  or  correction of violation of Environmental
Laws  associated  with  the  Assets  or  the  Retained  Assets,  or

               (ii)  any  event  or  condition  associated with the ownership or
operation  of  the Assets or the Retained Assets (including, without limitation,
the  presence  of  Hazardous Substances on, under, about or migrating to or from
the  Assets  or  the  Retained  Assets  or  the disposal or release of Hazardous
Substances  generated  by  operation  of  the  Assets  or the Retained Assets at
non-Asset  locations) including, without limitation, (A) the cost and expense of
any  investigation,  assessment,  evaluation,  monitoring, containment, cleanup,
repair,  restoration,  remediation,  or  other  corrective  action  required  or
necessary  under  Environmental Laws, (B) the cost or expense of the preparation
and  implementation  of any closure, remedial, corrective action, or other plans
required or necessary under Environmental Laws, and (C) the cost and expense for
any  environmental  or  toxic  tort  pre-trial,  trial,  or  appellate  legal or
litigation  support  work,

but only to the extent that such violation complained of under Section 2.1(a)(i)
or  such  events or conditions included under Section 2.1(a)(ii) occurred before
the  Closing  Date  (collectively,  "Covered  Environmental  Losses").

          (b)  POCC  shall  indemnify,  defend  and  hold  harmless  any  of the
Partnership  Entities from and against any Losses suffered or incurred by any of
the  Partnership  Entities  to  the extent that POCC is entitled to and receives
indemnification,  is  defended or held harmless against any such Losses from any
third-party  pursuant  to  any  agreement  between  any  third-party  and  POCC
(collectively,  "Pass-Through  Environmental  Losses").  In  furtherance of such
agreement,  POCC  agrees  to  use  its  best  commercially reasonable efforts to
pursue,  for  the  benefit of the Partnership Entities, any such indemnification
with  respect  to  which  it  might  be  entitled  if


                                        5

requested  by  the  Partnership;  provided that, the Partnership shall reimburse
POCC  for  all  costs  and  expenses  incurred  in connection with pursuing such
indemnity  on  behalf  of  the  Partnership.

          (c)  The  Partnership  shall  indemnify, defend and hold harmless POCC
from  and  against  Losses  suffered  or incurred by any of the POCC Entities by
reason  of  or  arising  out  of:

               (i)  any  violation  or  correction of violation of Environmental
Laws  associated  with  the  Assets,  or

               (ii)  any  event  or  condition  associated  with  ownership  or
operation  of  the  Assets  (including,  but  not  limited  to,  the presence of
Hazardous  Substances on, under, about or migrating to or from the Assets or the
disposal or release of Hazardous Substances generated by operation of the Assets
at  non-Asset locations) including, without limitation, (A) the cost and expense
of  any investigation, assessment, evaluation, monitoring, containment, cleanup,
repair,  restoration,  remediation,  or  other  corrective  action  required  or
necessary  under  Environmental Laws, (B) the cost or expense of the preparation
and  implementation  of any closure, remedial, corrective action, or other plans
required or necessary under Environmental Laws, and (C) the cost and expense for
any  environmental  or  toxic  tort  pre-trial,  trial,  or  appellate  legal or
litigation  support  work,

but  only  to the extent such violation complained of under Section 2.1(c)(i) or
such  events  or conditions included under Section 2.1(c)(ii) occurred after the
Closing  Date.

     2.2  ADDITIONAL  INDEMNIFICATION

          (a)  In  addition  to  and  not  in  limitation of the indemnification
provided  under  Sections  2.1(a)  and 2.1(b), POCC shall indemnify, defend, and
hold  harmless  the Partnership Entities from and against any Losses suffered or
incurred  by  the  Partnership  Entities  by  reason  of  or  arising  out  of

               (i)  any  events  and conditions associated with the ownership or
operation  of the Retained Assets, whether occurring before or after the Closing
Date,

               (ii)  the  failure of the Partnership Entities to be the owner of
such  valid  leasehold interests or fee ownership interests in and to the Assets
as  are  necessary  to  enable  the  Partnership Entities to continue to own and
operate  the  Assets and the Business in the same manner that the Assets and the
Business were owned and operated by the POCC Entities during the one-year period
immediately prior to the Closing Date to the extent that POCC is notified of any
of  the  foregoing  within  three  years  after  the  Closing  Date,

               (iii) the failure of the Partnership Entities to have any consent
or  permit  necessary  to  allow  the Partnership Entities to own or operate the
Assets and the Business in the same manner that the Assets and the Business were
owned  and  operated  by  the  POCC  Entities


                                        6

during  the  one-year period immediately prior to the Closing Date to the extent
that  POCC  is  notified  of  any  of the foregoing within three years after the
Closing  Date,

               (iv)  all  legal  actions  against  POCC,  including  without
limitation,  those  set  forth  on  Schedule  2.2  hereto,  and

               (v)  all  federal,  state  and  local  income  tax  liabilities
attributable  to  the  operation  of  the  Assets  prior  to  the  Closing Date.

          (b)  In  addition  to  and  not  in  limitation of the indemnification
provided  under  Sections  2.1(c),  or  under  the  Partnership  Agreement,  the
Partnership  shall  indemnify,  defend, and hold harmless the POCC Entities from
and  against  any  Losses  suffered  or  incurred by any of the POCC Entities by
reason  of  or  arising  out  of  events  and  conditions  associated  with:

               (i)  the  operation  of  the  Assets  and  the  Business,

               (ii) the performance of the Services by POCC and/or its employees
pursuant  to  this  Agreement  (provided  that  POCC  is  not  in breach of this
Agreement),  in  each  case  occurring  on or after the Closing Date (other than
Covered  Environmental  Losses which are provided for under Section 2.1), unless
in  any  such case such indemnification would not be permitted under Section 7.7
of  the  Partnership  Agreement,  and

          (c)  In  addition  to  and  not  in  limitation of the indemnification
provided  under  Sections 2.1(c) and 2.2(b), or under the Partnership Agreement,
the  Partnership  shall  indemnify,  for a period of three years from the fiscal
year  end  that  includes the Closing Date, the POCC Entities for federal income
tax  liabilities,  including  penalties  and  interest,  resulting  from  the
Distribution and restructuring transactions connected with it to the extent such
federal  income  tax  liabilities  exceed  $2.5  million  in  the  aggregate.

     2.3     INDEMNIFICATION  PROCEDURES.

          (a)  The  Indemnified  Party agrees that within a reasonable period of
time  after it becomes aware of facts giving rise to a claim for indemnification
under  this  Article  II,  it  will  provide  notice  thereof  in writing to the
Indemnifying  Party, specifying the nature of and specific basis for such claim.

          (b) The Indemnifying Party shall have the right to control all aspects
of  the  defense  of  (and any counterclaims with respect to) any claims brought
against the Indemnified Party that are covered by the indemnification under this
Article  II,  including,  without  limitation,  the  selection  of  counsel,
determination of whether to appeal any decision of any court and the settling of
any  such  matter or any issues relating thereto; provided however, that no such
settlement  shall  be  entered into without the consent of the Indemnified Party
unless  it  includes a full release of the Indemnified Party from such matter or
issues,  as  the  case  may  be.


                                        7

          (c)  The  Indemnified  Party  agrees  to  cooperate  fully  with  the
Indemnifying  Party,  with  respect  to all aspects of the defense of any claims
covered  by  the  indemnification  under  this  Article  II,  including, without
limitation,  the  prompt  furnishing  to  the  Indemnifying  Party  of  any
correspondence  or  other notice relating thereto that the Indemnified Party may
receive,  permitting  the  name  of  the  Indemnified  Party  to  be utilized in
connection  with such defense, the making available to the Indemnifying Party of
any  files,  records  or  other  information  of  the Indemnified Party that the
Indemnifying  Party  considers relevant to such defense and the making available
to  the  Indemnifying  Party of any employees of the Indemnified Party; provided
however,  that  in  connection  therewith  the  Indemnifying Party agrees to use
reasonable  efforts  to  minimize  the  impact  thereof on the operations of the
Indemnified  Party. In no event shall the obligation of the Indemnified Party to
cooperate  with the Indemnifying Party as set forth in the immediately preceding
sentence  be  construed  as imposing upon the Indemnified Party an obligation to
hire and pay for counsel in connection with the defense of any claims covered by
the  indemnification  set  forth  in this Article II; provided however, that the
Indemnified  Party  may,  at  its own option, cost and expense, hire and pay for
counsel  in  connection  with any such defense. The Indemnifying Party agrees to
keep  any  such counsel hired by the Indemnified Party reasonably informed as to
the  status of any such defense, but the Indemnifying Party shall have the right
to  retain  sole  control  over  such  defense.

          (d)  In determining the amount of any Losses for which the Indemnified
Party  is  entitled to indemnification under this Agreement, the gross amount of
the indemnification will be reduced by (i) any insurance proceeds realized or to
be  realized  by  the  Indemnified Party, and such correlative insurance benefit
shall  be  net of any incremental insurance premium that becomes due and payable
by  the  Indemnified  Party  as  a  result  of  such  claim and (ii) all amounts
recovered  or recoverable by the Indemnified Party under contractual indemnities
from  third  parties.

                                   ARTICLE III

                     SERVICES AND RELATED PARTY TRANSACTIONS

     3.1  SERVICES.  During  the  term of this Agreement, POCC agrees to provide
(either  directly  or through its Subsidiaries) on behalf of the General Partner
in  accordance  with  Article VII of the Partnership Agreement, the employees or
independent  contractors,  corporate  staff, support services and administrative
services  necessary to operate the Business (the "Services"). POCC shall perform
the  Services  in a manner that is substantially identical in nature and quality
to  the  services  performed by POCC for the Business during the one-year period
immediately  prior  to the Closing Date. The General Partner and the Partnership
agree  that  POCC  shall  be  reimbursed  for all costs and expenses incurred in
connection  with  the  performance  of  the  Services  as if it were the General
Partner  in  accordance  with  Section  7.4(b)  and  7.6(c)  of  the Partnership
Agreement.

     3.2 DESIGNATION OF AGENTS. In connection with the provision of the Services
by  the  employees  of  POCC, the General Partner, on behalf of the Partnership,
hereby  appoints  and empowers POCC and each current and future employee of POCC
who  is  fulfilling  a  job


                                        8

function  for  the Partnership in connection with the conduct by the Partnership
of  its  business  in the ordinary course, as agent of the Partnership with full
power  and  authority  to  execute and deliver on behalf of the Partnership, any
documents,  contracts,  governmental  filings  or other instruments commensurate
with,  but  limited  to,  such  job  function.  The  power and authority granted
pursuant  to  this  Section  3.2 to a person described in the preceding sentence
will  be  valid  only  for  so  long  as  such  person  is  employed  by  POCC.

     3.3 RIGHT TO OPERATE. POCC shall have the right, but not the obligation, to
act  as  operator of the Partnership's facilities to the same extent it acted as
operator of such facilities prior to the effective date of this Agreement for so
long  as  POCC  has  responsibilities  associated  with  such  facilities.

     3.4  RELATED  PARTY  TRANSACTIONS.  Each  of POCC, the General Partner, the
Partnership  and  the Operating Partnership agree that the execution or material
amendment of any "significant agreement" (as such term is defined below) must be
approved  by the Conflicts Committee. The term "significant agreement" means any
agreement  between  the  General  Partner,  the  Partnership  or  the  Operating
Partnership,  on  the  one  hand,  and  any POCC Entity, on the other hand, that
requires  aggregate  annual payments to or from any POCC Entity or POCC Entities
in  excess  of  $100,000.

     3.5  BREACH BY PENN OCTANE. In the event POCC fails to perform the Services
as  provided  in Section 3.1 and does not cure such failure within ten (10) days
of  receiving  written notice of same from the General Partner, the Partnership,
in  addition  to  any  other  remedies  at  law or in equity, may terminate this
Agreement and engage a third party for the provision of the Services. POCC shall
cooperate  in  good  faith  with  the  Partnership  and  the  General Partner in
transitioning  the  Services  to  any  such  third  party.

                                   ARTICLE IV

                                  MISCELLANEOUS

     4.1  INSURANCE MATTERS. POCC hereby agrees to cause each of the Partnership
Entities to be named as additional insureds in POCC's current insurance program,
which  is  described  on  Schedule  4.1 attached hereto. Each of the Partnership
Entities  shall  pay  for  its  allocated  cost of that insurance coverage in an
amount equal to POCC's cost of insuring the assets and operations of Partnership
Entity  and  generally  in  accordance  with  the  allocations  and  methodology
described  in  Schedule  4.1.

     4.2  CHOICE  OF  LAW;  SUBMISSION  TO JURISDICTION. This Agreement shall be
subject  to  and  governed  by  the  laws  of  the State of Texas, excluding any
conflicts-of-law  rule  or  principle  that  might  refer  the  construction  or
interpretation of this Agreement to the laws of another state. Each Party hereby
submits  to  the  jurisdiction of the state and federal courts in Harris County,
Texas.


                                        9

     4.3  NOTICE.  All  notices  or  requests  or  consents  provided for by, or
permitted to be given pursuant to, this Agreement must be in writing and must be
given  by  depositing same in the United States mail, addressed to the Person to
be notified, postpaid, and registered or certified with return receipt requested
or  by  delivering  such  notice  in person or by telecopier or telegram to such
Person. Notice given by personal delivery or mail shall be effective upon actual
receipt.  Notice  given by telegram or telecopier shall be effective upon actual
receipt  if  received  during  the  recipient's normal business hours, or at the
beginning  of  the  recipient's  next business day after receipt if not received
during  the recipient's normal business hours. All notices to be sent to a Party
pursuant  to  this  Agreement  shall be sent to or made at the address set forth
below such Party's signature to this Agreement, or at such other address as such
Party  may stipulate to the other parties in the manner provided in this Section
4.3.

     4.4  ENTIRE  AGREEMENT.  This Agreement constitutes the entire agreement of
the  Parties  relating  to  the  matters contained herein, superseding all prior
contracts  or  agreements,  whether  oral  or  written,  relating to the matters
contained  herein.

     4.5 TERMINATION. Unless earlier terminated as provided in this Section 4.5,
the  term  of  this  Agreement  shall be five (5) years from the date hereof and
shall  be  automatically  renewed for subsequent five (5) year terms, unless and
until  either  party  provides  written notice to the other party at least sixty
(60)  days  prior  to  the  expiration  of the initial five (5) year term or any
renewal  term  that  such  party  does  not  wish to renew this Agreement on the
expiration  of  the then current term. This Agreement, other than the provisions
of  Article  II, shall terminate on the earlier to occur of (i) ninety (90) days
after  either  party notifies the other party in writing that the Partnership is
no  longer  an  Affiliate  of  POCC and (ii) this Agreement is terminated by the
Partnership under Section 3.5. Termination of this Agreement shall not terminate
any  Indemnifying  Party's  continuing obligation of indemnification pursuant to
Article  II  of  this  Agreement  which obligations shall survive as provided in
Article  II.

     4.6  EFFECT OF WAIVER OR CONSENT. No waiver or consent, express or implied,
by  any Party to or of any breach or default by any Person in the performance by
such  Person  of  its obligations hereunder shall be deemed or construed to be a
consent  or  waiver  to  or of any other breach or default in the performance by
such  Person  of  the  same  or  any other obligations of such Person hereunder.
Failure  on  the  part  of  a  Party  to complain of any act of any Person or to
declare  any Person in default, irrespective of how long such failure continues,
shall  not  constitute  a waiver by such Party of its rights hereunder until the
applicable  statute  of  limitations  period  has  run.

     4.7  AMENDMENT  OR  MODIFICATION. This Agreement may be amended or modified
from  time  to  time  only  by  the written agreement of all the Parties hereto;
provided  however,  that  the Partnership may not, without the prior approval of
the  Conflicts  Committee,  agree  to  any  amendment  or  modification  of this
Agreement.  Each  such  instrument  shall  be  reduced  to  writing and shall be
designated  on  its  face  an  "Amendment"  or  an "Addendum" to this Agreement.


                                       10

     4.8  ASSIGNMENT.  No  Party  shall  have  the right to assign its rights or
obligations  under  this  Agreement  without  the  consent  of the other Parties
hereto.

     4.9  COUNTERPARTS.  This  Agreement  may  be  executed  in  any  number  of
counterparts  with  the  same  effect as if all signatory parties had signed the
same document. All counterparts shall be construed together and shall constitute
one  and  the  same  instrument.

     4.10  SEVERABILITY.  If  any provision of this Agreement or the application
thereof  to any Person or circumstance shall be held invalid or unenforceable to
any  extent,  the  remainder  of  this  Agreement  and  the  application of such
provision  to  other  Persons or circumstances shall not be affected thereby and
shall  be  enforced  to  the  greatest  extent  permitted  by  law.

     4.11  FURTHER  ASSURANCES.  In  connection  with  this  Agreement  and  all
transactions  contemplated by this Agreement, each signatory party hereto agrees
to  execute and deliver such additional documents and instruments and to perform
such additional acts as may be necessary or appropriate to effectuate, carry out
and  perform  all  of the terms, provisions and conditions of this Agreement and
all  such  transactions.

     4.12  LAWS AND REGULATIONS. Notwithstanding any provision of this Agreement
to  the  contrary, no Party to this Agreement shall be required to take any act,
or  fail to take any act, under this Agreement if the effect thereof would be to
cause  such  Party  to  be  in violation of any applicable law, statute, rule or
regulation.

     4.13  NEGOTIATION  OF  RIGHTS  OF  LIMITED  PARTNERS,  ASSIGNEES, AND THIRD
PARTIES.  The provisions of this Agreement are enforceable solely by the Parties
to  this  Agreement, and no limited partner, member, assignee or other Person of
the Partnership or General Partner shall have the right, separate and apart from
the  Partnership  or  the  General  Partner,  to  enforce  any provision of this
Agreement  or  to compel any Party to this Agreement to comply with the terms of
this  Agreement.


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                                       11

     IN WITNESS WHEREOF, the Parties hereto have executed this Omnibus Agreement
on,  and  effective  as  of,  the  date  first  written  above.

                                    RIO VISTA ENERGY PARTNERS, L.P.

                                    By: RIO VISTA GP LLC,
                                        On behalf of itself and on behalf of
                                        Partnership as its General Partner


                                        By:/s/ Richard Shore, Jr.
                                           -------------------------
                                        Name: Richard Shore, Jr.
                                        Title: President

                                    RIO VISTA OPERATING PARTNERSHIP L.P.

                                    By: RIO VISTA OPERATING GP LLC

                                        By: RIO VISTA ENERGY PARTNERS
                                            L.P., its sole member

                                            By:    RIO VISTA GP LLC


                                            By:/s/ Richard Shore, Jr.
                                               -------------------------
                                                   Richard Shore, Jr.,
                                                   President


                                    PENN OCTANE CORPORATION


                                    By: /s/ Jerome B. Richter
                                        ------------------------
                                    Name: Jerome B. Richter
                                    Title: Chief Executive Officer


                                       12

                                  SCHEDULE 2.2
                                  ------------

     PENDING LEGAL ACTIONS AGAINST PENN OCTANE CORPORATION

     NONE


                                       13

                                   SCHEDULE 4
                                   ----------

                                    INSURANCE


                                       14