LOAN AGREEMENT

THIS LOAN AGREEMENT (this "Agreement") is dated as of March 1, 1999, between
ValorInvest Ltd., an Irish Corporation ("Lender") and Marine Shuttle Operations,
Inc., a Nevada corporation ("Borrower").

The parties agree as follows:

1. Loan. Lend will provide the Borrower with a loan in the amount of up to
US$6,000,000 (the "Loan") payable to the Borrower in instalments as mutually
agreed upon by the parties in US$250,000 increments not to exceed US$1,000,000
per month unless agreed to by the Lender. The Loan shall be evidenced by
Borrower's non-negotiable promissory note containing terms mutually agreed to by
the parties.

2. Interest. The Loan shall bear interest at a rate of seven and one half
percent (7,5%) per annum.

3. Term and Termination. The term of the Loan shall commence on the date of the
first payment of the Loan to Borrower and will be due and payable upon the
earlier of December 31, 1999 or the consummation of an equity financing for
gross proceeds of at least US$10,000,000, unless extended by the Lender.

4.    Notice. All notices, requests, demands and other communications required
      or permitted hereunder must be in writing and deemed given and effective
      when personally delivered or send by facsimile with confirmation of
      receipt or when deposited in the mail with postage prepared to the party
      to which the same is directed at the following addresses (or at such other
      addresses as will be given in writing by the parties to one another):

      To the Borrower:
                                       Marine Shuttle Operations Inc.
                                       Attention: Mr. Franz Eder
                                       4410 Montrose Boulevard
                                       Houston, Texas 77006
                                       Tel: 713-5297498
                                       Fax: 713-5293332

with copy to:                          Besner Kreifels Weber
                                       Dr. Hubert Besner
                                       Widenmayerstr. 41, 80538 Munich - Germany
                                       Tel: 49-89-2199920
                                       Fax: 49-89-21999233


                                      -80-
<PAGE>

To the Lender:                         ValorInvest Ltd.
                                       Attention: Mr. Pierre Besuchet
                                       29 Quai des Bergues
                                       1201 Geneva, Switzerland
                                       Tel: 41-22-7325355
                                       Fax: 41-22-7325695

with copy to:                          Michael H. Chanin, Esquire
                                       Powell, Goldstein, Frazer & Murphy LLP
                                       1001 Pennsylvania Avenue, NW., Suite 600
                                       Washington, DC 20004
                                       Tel: (202) 624-7235
                                       Fax: (202) 624-7222

5. Miscellaneous.

      (a) Assignment. The parties may not assign any rights or delegate any
duties they have assumed hereunder without the prior written consent of the
other party. This Agreement is personal to the parties.

      (b) Governing Law an Choice of Forum. This Agreement will be governed by
and construed in accordance with the internal law of Switzerland. The parties
agree that any appropriate court located in Geneva will have exclusive
jurisdiction of any case or controversy arising under or in connection with this
Agreement and will be a proper forum in which to adjudicate such case or
controversy. The parties expressly consent to personal jurisdiction and venue in
such courts.

      (c) Entire Agreement / Admendement. This Agreement embodies the entire
agreement of the parties hereto relating to the subject matter hereof and
supersedes all oral agreements, and to the extent inconsistent with the terms
hereof, all other written agreements. This Agreement may not be modified,
amended, supplemented or terminated except by a written instrument executed by
all parties hereto.

      (d) Severability. Each of the covenants and agreements herein above
contained will be deemed separate, severable and independent covenants, and in
the event that any covenant will be declared invalid by any court of competent
jurisdiction, such invalidity will not in any manner affect or impair the
validity or enforceability of any other part or provision of such covenant or of
any other covenant contained herein.

      (e) Captions and Section Headings. Captions and section headings used
herein are for conveniece only an dare not a part of this Agreement and will not
be used in construing it.

      (f) Fax Execution. This Agreement may be executed by delivery of executed
signature pages by fax and such fax execution will be effective for all
purposes.


                                      -81-
<PAGE>

SIGNATURES APPEAR ON THE FOLLOWING PAGE


                                      -82-
<PAGE>

                                        EXECUTED AS OF MARCH 1, 1999

                                        VALORINVEST LTD.

                                        -------------------------------------
                                        By: Pierre Besuchet
                                        Title: Director and Secretary


                                        MARINE SHUTTLE OPERATIONS, INC.

                                        -------------------------------------
                                        By: Franz Eder
                                        Title: President


                                      -83-
<PAGE>

                         NON-NEGOTIABLE PROMISSORY NOTE
                               U.S. $6,000,000.00
                                  March 1, 1999

FOR VALUE RECEIVED, the undersigned MARINE SHUTTLE OPERATIONS, INC.
("Borrower"), does hereby promise to pay to the order of VALORINVEST LTD.
("Lender"), with offices at 29 Quai des Bergues, Geneva, Switzerland 1201, and
at said offices or at such other place or places as the holder hereof may from
time to time designate in writing, the principal sum of SIX MILLION AND 00/100
UNITED STATES DOLLARS (U.S. $6,000,000), or so much thereof as shall have been
advanced hereunder by Lender to Borrower together with interest thereon as
provided below.

      1. Interest. Interest will accrue on the outstanding principal amount of
this Note at the rate of seven and one half percent (7.5%) per annum from the
date of each advance, and until all amounts outstanding under this Note have
been paid in full.

      2. Payments. Interest, principal and all other sums payable hereunder
(collectively, the "Obligations") shall be payable, without any offset,
reduction, counterclaim or recoupment whatsoever, in lawful money of the United
States of America which shall be legal tender in payment of all debts and dues,
public and private, at the time of payment, and shall be due and payable as
follows unless extended by the Lender:

      (a) The Obligations shall be repaid in full with the first gross proceeds
      from any Borrower equity financing generating at least Ten Million Dollars
      ($10,000,000); or

      (b) If not sooner paid (whether by acceleration or otherwise), the entire
      balance of the Obligations shall be due and payable on December 31, 1999,
      (collectively, the "Maturity Date").

      3. Advances. Upon receiving a properly executed original of this Note and
upon the satisfaction of the conditions precedent to any advance as set forth
herein, Lender shall make available the proceeds of the loan. Advances shall be
made available in $250,000 increments upon three (3) days written notice of
demand by Borrower; provided, however, that Lender is not required to advance
more than $1,000,000 in any single month. Advances are limited in the aggregate
to the stated principal amount of this Note; this is not a revolving line of
credit. The following shall be conditions precedent to any advance hereunder
(except to the extent and in the manner expressly waived by Lender, and any such
conditions waived by Lender may be reimposed as a condition of subsequent
advances):

      (a) Borrower shall have executed and delivered this Note to the Lender.

      (b) All representations and warranties made by Borrower in this Note shall
      be true, complete and correct on and as of the date of the making of any
      advance hereunder as though such representations and warranties were made
      anew on such date.


                                      -84-
<PAGE>

      (c) There shall not have occurred and be continuing any default in the
      performance or observance of any of the covenants, agreements, or
      conditions to be performed or observed by Borrower under this Note or in
      connection with any other obligations of Borrower to Lender, nor shall
      there have occurred and be continuing any event, condition, or
      circumstances which, with notice or the passage of time, or both, would
      constitute a breach in any material respect of any representation,
      covenant, or warranty by Borrower or a default under this Note or in
      connection with any other obligations of Borrower to Lender.

      4. Application of Payments. All payments shall be applied first on account
of late charges, if any, then to Lender's costs of collection (including,
without limitation, reasonable attorneys' fees and expenses), if any, then, to
accrued and unpaid interest, and the balance to the reduction of principal. For
the purposes of computing interest on the debt evidenced hereby, interest shall
be calculated on the basis of a year consisting of three hundred sixty (360)
days, and shall be charged on the basis of the actual number of calendar days
that the principal amount advanced remains unpaid to the Lender.

      5. Default; Remedies. If default be made in the performance of any term,
condition or covenant contained in this Note, or in connection with any other
obligations of Borrower to Lender, and such default shall not have been cured
under any cure provisions applicable to such default, then and in any such
event, the Obligations, in their entirety, shall at once become due and payable
at the option of the Lender without further notice. Failure of the Lender to
exercise the option to accelerate payment in the event of any default shall not
constitute a waiver of the right to exercise the same in the event of any
subsequent default.

      6. Prepayment. The privilege is reserved to Borrower to prepay the
indebtedness evidenced hereby, in whole or in part, at any time or from time to
time, without prepayment premium or penalty, provided, however, that Borrower
shall provide prior written notice to Lender of the intent to prepay ten (10)
business days in advance of such prepayment.

      7. Attorney's Fees. In the event counsel is employed by the Lender to
enforce the provisions of this Note, Borrower shall pay upon demand reasonable
attorneys' fees so incurred by Lender, and all other costs and expenses
connected with such enforcement.

      8. Waivers. The Borrower hereby waives presentment, protest and demand,
notice of protest and notice of dishonor of this Note.

      9. Notices. All notices hereunder shall be given in writing and shall be
effective (a) five (5) days after being mailed by first class and certified or
registered mail, return receipt requested, with proper postage prepaid or (b)
two (2) business days after being delivered to an established over-night
delivery service, with costs for "next day" delivery prepaid, addressed in
either case, if to the Borrower at the address provided at the end of this Note;
and addressed if to the Lender at ValorInvest Ltd., 29 Quai des Bergues, Geneva,
Switzerland 1201, Attention: Mr. Pierre Besuchet, with a copy to Powell,
Goldstein, Frazer & Murphy LLP, 1001 Pennsylvania Avenue, NW., Suite 600,
Washington, DC 20004, attention: Michael H.


                                      -85-
<PAGE>

Chanin, Esquire, or in either case to such other address as such party may from
time to time designate to the other by like written notice given at least ten
(10) days prior to the date such change becomes effective.

      10. Severability. In the event any provision (or any part of any
provision) contained in this Note shall for any reason be finally held by a
court of competent jurisdiction to be invalid, illegal or unenforceable in any
respect, such invalidity, illegality or unenforceability shall not affect any
other provision (or remaining part of the affected provision) of this Note; but
this Note shall be construed as if such invalid, illegal or unenforceable
provision (or part thereof) had never been contained herein, but only to the
extent it is invalid, illegal or unenforceable.

      11. Successors and Assigns. This Note shall apply to and bind the Borrower
and the Lender and each of their respective successors. This Note is
non-negotiable and may not be assigned by Lender.

      12. Commercial Purpose. The Borrower warrants that the loan evidenced by
this Note is being made solely to acquire or carry on a business or commercial
enterprise, and that the Borrower is a business or commercial organization. The
Borrower further covenants that the loan evidenced by this Note shall be
construed for all purposes as a commercial purpose loan.

      13. Time is of the Essence. Time is of the essence as to each and every
provision of this Note.

      14. Governing Law and Choice of Forum. This Note will be governed by and
construed in accordance with the internal laws of Switzerland. The Borrower
agrees that any appropriate court located in Geneva will have exclusive
jurisdiction of any case or controversy arising under or in connection with this
Note and will be a proper forum in which to adjudicate such case or controversy.
The Borrower expressly consents to personal jurisdiction and venue in such
courts.

SIGNATURES APPEAR ON THE FOLLOWING PAGE

      WITNESS the execution hereof by the Borrower on the date first hereinabove
written, with the intent that this shall be an instrument under seal.


                                      -86-
<PAGE>

                                    BORROWER:

                    WITNESS: MARINE SHUTTLE OPERATIONS, INC.

                           4410 Montrose Boulevard
                           Houston, Texas 77006


                           By:                                            (SEAL)
------------------------      --------------------------------------------
Name                          Name: Franz Eder
                              Title: President

                           Bank Wiring Instructions


                                      -87-