<PAGE>   1

                                                                    EXHIBIT 10.8


                    MASTER CONFIDENTIAL DISCLOSURE AGREEMENT



                                     BETWEEN



                             MERCURY AIR GROUP, INC.



                                       AND



                                 MERCFUEL, INC.







                          EFFECTIVE AS OF ______, 2001





<PAGE>   2


                                TABLE OF CONTENTS

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                                                                                                               PAGE
                                                                                                               -----
<S>                                                                                                            <C>
ARTICLE 1 - DEFINITIONS....................................................................................       1

         Section 1.1       Ancillary Agreements............................................................       1

         Section 1.2       Confidential Information........................................................       2

         Section 1.3       Confidentiality Period..........................................................       2

         Section 1.4       Disclosing Party................................................................       2

         Section 1.5       Distribution Date...............................................................       2

         Section 1.6       Highly Confidential Information.................................................       2

         Section 1.7       Master Separation and Distribution Agreement....................................       2

         Section 1.8       Person..........................................................................       2

         Section 1.9       Receiving Party.................................................................       3

         Section 1.10      Separation Date.................................................................       3

         Section 1.11      Subsidiary......................................................................       3

         Section 1.12      Third Party.....................................................................       3

         Section 1.13      Transaction Agreements..........................................................       3

ARTICLE 2 - CONFIDENTIALITY................................................................................       3

         Section 2.1       Confidentiality and Non-Use Obligations.........................................       3

         Section 2.2       Disclosure to Sublicenses.......................................................       3

         Section 2.3       Residuals.......................................................................       4

         Section 2.4       Compelled Disclosure............................................................       4

         Section 2.5       No Restriction on Disclosing Party..............................................       4

         Section 2.6       No Restriction on Reassignment..................................................       4

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                                       i
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<TABLE>
<S>                                                                                                            <C>
         Section 2.7       Third Party Restrictions......................................................         4

ARTICLE 3 - WARRANTY DISCLAIMER..........................................................................         4

ARTICLE 4 - ADDITIONAL OBLIGATIONS.......................................................................         5

ARTICLE 5 - TERMS AND TERMINATION........................................................................         5

         Section 5.1       Term..........................................................................         5

         Section 5.2       Survival......................................................................         5

ARTICLE 6 - DISPUTE RESOLUTION...........................................................................         5

         Section 6.1       Mediation.....................................................................         5

         Section 6.2       Arbitration...................................................................         6

         Section 6.3       Court Action..................................................................         6

         Section 6.4       Continuity of Service and Performance.........................................         6

ARTICLE 7 - MISCELLANEOUS PROVISIONS.....................................................................         6

         Section 7.1       Export Restrictions...........................................................         6

         Section 7.2       No Implied Licenses...........................................................         7

         Section 7.3       Infringement Suits............................................................         7

         Section 7.4       No Other Obligations..........................................................         7

         Section 7.5       Entire Agreement..............................................................         7

         Section 7.6       Governing Law.................................................................         7

         Section 7.7       Interpretation................................................................         7

         Section 7.8       Notices.......................................................................         8

         Section 7.9       Nonassignability..............................................................         8

         Section 7.10      Severability..................................................................         8

         Section 7.11      Failure or Indulgence Not Waiver; Remedies Cumulative.........................         9

         Section 7.12      Amendment.....................................................................         9

         Section 7.13      Counterparts..................................................................         9


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<PAGE>   4

                    MASTER CONFIDENTIAL DISCLOSURE AGREEMENT

     This Master Confidential Disclosure Agreement (the "Agreement") is
effective as of ________, 2001 (the "Effective Date"), between Mercury Air
Group, Inc., a Delaware corporation ("MAG"), having an office at 5456 McConnell
Avenue, Los Angeles, California, 90066 and MercFuel, Inc., a Delaware
corporation ("MercFuel"), having an office at 5456 McConnell Avenue, Los
Angeles, California, 90066.

     WHEREAS, the Board of Directors of MAG has determined that it is in the
best interest of MAG and its stockholders to separate MAG's existing businesses
into two independent businesses;

     WHEREAS, as part of the foregoing, MAG and MercFuel entered into a Master
Separation and Distribution Agreement (as defined below), which provides, among
other things, for the separation of certain MercFuel assets and MercFuel
liabilities, the distribution of MercFuel stock, and the execution and delivery
of certain other agreements in order to facilitate and provide for the
foregoing; and

     WHEREAS, also as part of the foregoing, the parties further desire to enter
into this Agreement to provide for the protection of their Confidential
Information (as defined below).

     NOW, THEREFORE, in consideration of the mutual promises of the parties, and
of good and valuable consideration, it is agreed by and between the parties as
follows:

                                    ARTICLE 1
                                   DEFINITIONS

     For the purpose of this Agreement the following capitalized terms are
defined in this Article 1 and shall have the meaning specified herein:

     Section 1.1 Ancillary Agreements. Ancillary Agreements means the items and
agreements listed in Section 2.1 of the Master Separation and Distribution
Agreement and all agreements and documents contemplated by such agreements.

     Section 1.2 Confidential Information.

          (a) Confidential Information means business information, technical
     data, know-how and other information which is not otherwise in the public
     domain and of which the owner actively undertakes to restrict or control
     the disclosure to Third Parties in a manner reasonably intended to maintain
     its confidentiality, and which (i) the Disclosing Party disclosed to the
     Receiving Party or the Receiving Party had access to on or before the
     Separation Date, (ii) is the subject of any Transaction Agreement and known
     to or in the possession of the Receiving Party as of the Separation Date or
     (iii) is disclosed to the Receiving Party pursuant to any Transaction
     Agreement for a period of



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<PAGE>   5

     one (1) year after the Effective Date. Confidential Information may include
     information relating to, by way of example, research, products, services,
     customers, markets, software, developments, inventions, processes, designs,
     drawings, engineering, marketing or finances, and may be in writing,
     disclosed orally or learned by inspection of computer programming code,
     equipment or facilities.

          (b) Confidential Information of Third Parties that is known to, in the
     possession of or acquired by a Receiving Party pursuant to a relationship
     with the Disclosing Party shall be deemed the Disclosing Party's
     Confidential Information for purposes herein.

          (c) Notwithstanding the foregoing provisions of this Section 1.2,
     Confidential Information shall exclude information that: (i) was in the
     Receiving Party's possession before receipt from the Disclosing Party and
     obtained from a source other than the Disclosing Party and other than
     through the prior relationship of the Disclosing Party and the Receiving
     Party before the Separation Date; (ii) is or becomes a matter of public
     knowledge through no fault of the Receiving Party; (iii) is rightfully
     received by the Receiving Party from a Third Party without a duty of
     confidentiality; (iv) is disclosed by the Disclosing Party to a Third Party
     without a duty of confidentiality on the Third Party; (v) is independently
     developed by the Receiving Party; or (vi) is disclosed by the Receiving
     Party with the Disclosing Party's prior written approval.

     Section 1.3 Confidentiality Period. Confidentiality Period means, (a) with
respect to Confidential Information that is not Highly Confidential Information,
five (5) years, and (b) with respect to Highly Confidential Information, in
perpetuity, after either (i) the Separation Date with respect to Confidential
Information of the Disclosing Party that is known to or in the possession of the
Receiving Party as of the Separation Date or (ii) the date of disclosure with
respect to Confidential Information that is disclosed by the Disclosing Party to
the Receiving Party after the Separation Date.

     Section 1.4 Disclosing Party. Disclosing Party means the party owning or
disclosing the relevant Confidential Information.

     Section 1.5 Distribution Date. Distribution Date has the meaning set forth
in the Master Separation and Distribution Agreement.

     Section 1.6 Highly Confidential Information. Highly Confidential
Information means Confidential Information that is integral to products that are
commercially released or for which substantial steps have been taken to
commercialization.

     Section 1.7 Master Separation and Distribution Agreement. Master Separation
and Distribution Agreement means that certain Master Separation and Distribution
Agreement between MAG and MercFuel.

     Section 1.8 Person. Person means an individual, a partnership, a
corporation, a limited liability company, an association, a joint stock company,
a trust, a joint venture, an


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<PAGE>   6


unincorporated organization, and a governmental entity or any department, agency
or political subdivision thereof.

     Section 1.9 Receiving Party. Receiving Party means the non-owning party or
recipient of the relevant Confidential Information.

     Section 1.10 Separation Date. Separation Date means 12:01 a.m., Pacific
Time, _______________, 2001, or such other date as may be fixed by the Board of
Directors of MAG.

     Section 1.11 Subsidiary. Subsidiary of any Person means a corporation or
other organization, whether incorporated or unincorporated, of which at least a
majority of the securities or interests having by the terms thereof ordinary
voting power to elect at least a majority of the board of directors or others
performing similar functions with respect to such corporation or other
organization is directly or indirectly owned or controlled by such Person or by
any one or more of its Subsidiaries, or by such Person and one or more of its
Subsidiaries; provided, however, that no Person that is not directly or
indirectly wholly-owned by any other Person shall be a Subsidiary of such other
Person unless such other Person controls, or has the right, power or ability to
control, that Person. For purposes of this Agreement, MercFuel shall be deemed
not to be a subsidiary of MAG.

     Section 1.12 Third Party. Third Party means a Person other than MAG and its
Subsidiaries and MercFuel and its Subsidiaries.

     Section 1.13 Transaction Agreements. Transaction Agreements mean the Master
Separation and Distribution Agreement and the Ancillary Agreements.

                                    ARTICLE 2
                                 CONFIDENTIALITY


     Section 2.1 Confidentiality and Non-Use Obligations. During the
Confidentiality Period, the Receiving Party shall (i) protect the Confidential
Information of the Disclosing Party by using the same degree of care, but no
less than a reasonable degree of care, to prevent the unauthorized use,
dissemination, or publication of the Confidential Information as Receiving Party
uses to protect its own confidential information of a like nature, (ii) not use
such Confidential Information in violation of any use restriction in any
Transaction Agreement, and (iii) not disclose such Confidential Information to
any Third Party, except as expressly permitted under this Agreement, in the
Transaction Agreements or in any other agreements entered into between the
parties in writing, without prior written consent of the Disclosing Party.

     Section 2.2 Disclosure to Sublicensees. The Receiving Party has the right
to disclose to its sublicensees permitted under a Transaction Agreement portions
of Confidential Information as reasonably necessary in the exercise of the
Receiving Party's sublicense rights under such Transaction Agreement, subject to
the sublicensee's agreement in writing to


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confidentiality and non-use terms at least as protective of the Disclosing Party
as the provisions of this Agreement.

     Section 2.3 Residuals. Notwithstanding any other provision of this
Agreement, the Receiving Party shall be free, and the Disclosing Party hereby
grants to the Receiving Party, except as otherwise provided in this Section 2.3,
the right, to use or exploit for any purpose and without restriction the
Residuals resulting from access to or work with the Confidential Information of
the Disclosing Party. "Residuals" means information retained in the unaided
memory of an individual who has had access to Confidential Information. The
Receiving Party shall have no obligation to pay royalties for any use of
Residuals. However, this Section 2.3 does not grant the Receiving Party any
rights under any patents or copyrights of the Disclosing Party.

     Section 2.4 Compelled Disclosure. If the Receiving Party or any of its
respective Subsidiaries believes that it will be compelled by a court or other
authority to disclose Confidential Information of the Disclosing Party, it shall
(i) give the Disclosing Party prompt written notice so that the Disclosing Party
may take steps to oppose such disclosure, and (ii) cooperate with the Disclosing
Party in its attempts to oppose such disclosure. If the Receiving Party complies
with the above, it shall not be prohibited from complying with such requirement
to disclose, but shall take all reasonable steps to make such disclosure subject
to a suitable protective order or otherwise prevent unrestricted or public
disclosure.

     Section 2.5 No Restriction on Disclosing Party. Nothing in this Agreement
shall restrict the Disclosing Party from using, disclosing, or disseminating its
own Confidential Information in any way.

     Section 2.6 No Restriction on Reassignment. This Agreement shall not
restrict reassignment of the Receiving Party's employees.

     Section 2.7 Third Party Restrictions. Nothing in the Agreement supersedes
any restriction imposed by Third Parties on their Confidential Information, and
there is no obligation on the Disclosing Party to conform Third Party agreements
to the terms of this Agreement.

                                    ARTICLE 3
                               WARRANTY DISCLAIMER

     EACH PARTY ACKNOWLEDGES AND AGREES THAT ALL CONFIDENTIAL INFORMATION IS
PROVIDED ON AN "AS IS, WHERE IS" BASIS AND THAT NEITHER PARTY NOR ANY OF ITS
SUBSIDIARIES HAS MADE OR WILL MAKE ANY WARRANTY WHATSOEVER, EXPRESS, IMPLIED OR
STATUTORY, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, ENFORCEABILITY OR
NON-INFRINGEMENT.



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                                    ARTICLE 4
                          CONFIDENTIALITY OF AGREEMENT

     Each party agrees that the terms and conditions of the Transaction
Agreements marked as confidential shall be treated as Confidential Information
and that neither party will disclose such terms or conditions to any Third Party
without the prior written consent of the other party, provided, however, that
each party may disclose such terms and conditions of such agreements marked as
confidential:

     (a)  as required by any court or other governmental body (subject to
          Section 2.4);

     (b)  as otherwise required by law (subject to Section 2.4);

     (c)  in confidence, to legal counsel of the parties, accountants, and other
          professional advisors;

     (d)  in confidence to banks, investors and other financing sources and
          their advisors;

     (e)  in connection with the enforcement of this Agreement or rights under
          this Agreement; or

     (f)  in confidence, in connection with an actual or prospective merger or
          acquisition or similar transaction.

                                    ARTICLE 5
                              TERM AND TERMINATION

     Section 5.1 Term. This Agreement shall remain in full force and effect
unless and until terminated by the mutual written agreement of the parties.

     Section 5.2 Survival. Articles 2 (with respect to Confidential Information
acquired or disclosed prior to the date of termination), 3, 4, 6, 7 and 8 shall
survive any termination of this Agreement.

                                    ARTICLE 6
                               DISPUTE RESOLUTION

     Section 6.1 Mediation. If a dispute, controversy or claim ("Dispute")
arises between the parties relating to the interpretation or performance of this
Agreement or the grounds for the termination hereof, appropriate senior
executives (e.g. director or V.P. level) of each party who shall have the
authority to resolve the matter shall meet to attempt in good faith to negotiate
a resolution of the Dispute prior to pursuing other available remedies. The
initial meeting between the appropriate senior executives shall be referred to
herein as the "Dispute Resolution Commencement Date". Discussions and
correspondence relating to trying to resolve such


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<PAGE>   9


Dispute shall be treated as confidential information developed for the purpose
of settlement and shall be exempt from discovery or production and shall not be
admissible. If the senior executives are unable to resolve the Dispute within
thirty (30) days from the Dispute Resolution Commencement Date, and either party
wishes to pursue its rights relating to such Dispute, then the Dispute will be
mediated by a mutually acceptable mediator appointed pursuant to the mediation
rules of JAMS/Endispute within thirty (30) days after written notice by one
party to the other demanding non- binding mediation. Neither party may
unreasonably withhold consent to the selection of a mediator or the location of
the mediation. Both parties will share the costs of the mediation equally,
except that each party shall bear its own costs and expenses, including
attorney's fees, witness fees, travel expenses, and preparation costs. The
parties may also agree to replace mediation with some other form of non-binding
or binding ADR.

     Section 6.2 Arbitration. Any Dispute which the parties cannot resolve
through mediation within ninety (90) days of the Dispute Resolution Commencement
Date, unless otherwise mutually agreed, shall be submitted to final and binding
arbitration under the then current Commercial Arbitration Rules of the American
Arbitration Association ("AAA"), by three (3) arbitrators in Los Angeles County,
California. Such arbitrators shall be selected by the mutual agreement of the
parties or, failing such agreement, shall be selected according to the aforesaid
AAA rules. The arbitrators will be instructed to prepare and deliver a written,
reasoned opinion stating their decision within thirty (30) days of the
completion of the arbitration. The prevailing party in such arbitration shall be
entitled to expenses, including costs and reasonable attorneys' and other
professional fees, incurred in connection with the arbitration (but excluding
any costs and fees associated with prior negotiation or mediation). The decision
of the arbitrator shall be final and non-appealable and may be enforced in any
court of competent jurisdiction. The use of any ADR procedures will not be
construed under the doctrine of laches, waiver or estoppel to adversely affect
the rights of either party.

     Section 6.3 Court Action. Any Dispute regarding the following is not
required to be negotiated, mediated or arbitrated prior to seeking relief from a
court of competent jurisdiction: breach of any obligation of confidentiality;
infringement, misappropriation, or misuse of any intellectual property right;
any other claim where interim relief from the court is sought to prevent serious
and irreparable injury to one of the parties or to others.

     Section 6.4 Continuity of Service and Performance. Unless otherwise agreed
in writing, the parties will continue to provide service and honor all other
commitments under this Agreement and each Ancillary Agreement during the course
of dispute resolution pursuant to the provisions of this Article 6 with respect
to all matters not subject to such dispute, controversy or claim.

                                    ARTICLE 7
                            MISCELLANEOUS PROVISIONS

     Section 7.1 Export Restrictions. Both parties shall adhere to all
applicable laws, regulations and rules relating to the export of technical data,
and shall not export or reexport any technical data, any products received from
Disclosing Party, or the direct product of such


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<PAGE>   10


technical data, to any proscribed country listed in such applicable laws,
regulations and rules unless properly authorized.

     Section 7.2 No Implied Licenses. Nothing contained in this Agreement shall
be construed as conferring any rights by implication, estoppel or otherwise,
under any intellectual property right, other than the rights expressly granted
in this Agreement with respect to Confidential Information. Neither party is
required hereunder to furnish or disclose to the other any technical or other
information.

     Section 7.3 Infringement Suits. Neither party shall have any obligation
hereunder to institute any action or suit against Third Parties for
misappropriation of any of its Confidential Information or to defend any action
or suit brought by a Third Party that alleges infringement of any intellectual
property rights by the Receiving Party's authorized use of the Disclosing
Party's Confidential Information.

     Section 7.4 No Other Obligations. NEITHER PARTY ASSUMES ANY
RESPONSIBILITIES OR OBLIGATIONS WHATSOEVER, OTHER THAN THE RESPONSIBILITIES AND
OBLIGATIONS EXPRESSLY SET FORTH IN THIS AGREEMENT OR A SEPARATE WRITTEN
AGREEMENT BETWEEN THE PARTIES.

     Section 7.5 Entire Agreement. This Agreement, the Master Separation and
Distribution Agreement and the other Ancillary Agreements and the Exhibits and
Schedules referenced or attached hereto and thereto constitute the entire
agreement between the parties with respect to the subject matter hereof and
thereof and shall supersede all prior written and oral and all contemporaneous
oral agreements and understandings with respect to the subject matter hereof and
thereof. Notwithstanding the foregoing, the parties agree that any agreements
entered into between them on or after the Separation Date for the protection of
specific Confidential Information shall supersede the terms of this Agreement
with respect to such Confidential Information.

     Section 7.6 Governing Law. This Agreement shall be construed in accordance
with and all Disputes hereunder shall be governed by the laws of the State of
California, excluding its conflict of law rules and the United Nations
Convention on Contracts for the International Sale of Goods. The Superior Court
of Los Angeles County and/or the United States District Court for the Central
District of California shall have jurisdiction and venue over all Disputes
between the parties that are permitted to be brought in a court of law pursuant
to Section 6 above.

     Section 7.7 Interpretation. The headings contained in this Agreement, in
any Exhibit hereto and in the table of contents to this Agreement are for
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement. Any capitalized term used in any Exhibit but
not otherwise defined therein, shall have the meaning assigned to such term in
this Agreement. When a reference is made in this Agreement to an Article or a
Section or an Exhibit, such reference shall be to an Article or Section of, or
an Exhibit to, this Agreement unless otherwise indicated.




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     Section 7.8 Notices. Notices, offers, requests or other communications
required or permitted to be given by either party pursuant to the terms of this
Agreement shall be given in writing to the respective parties to the following
addresses:


if to MAG:                                Copy to:

Mercury Air Group, Inc.                   McBreen & Kopko
5456 McConnell Avenue                     20 North Wacker Drive, Suite 2520
Los Angeles, California 90066             Chicago, Illinois  60606
Attention:  Chief Executive Officer       Attention:  Frederick H. Kopko, Jr.
Fax: (310) 827-0650                       Fax:  (312) 332-2657

if to MercFuel:                           Copy to:

MercFuel, Inc.                            McBreen & Kopko
5456 McConnell Avenue                     20 North Wacker Drive, Suite 2520
Los Angeles, California 90066             Chicago, Illinois  60606
Attention:  Chief Executive Officer       Attention:  Frederick H. Kopko, Jr.
Fax:  (310) 827-0650                      Fax:  (312) 332-2657


or to such other address as the party to whom notice is given may have
previously furnished to the other in writing as provided herein. Any notice
involving non-performance, termination, or renewal shall be sent by hand
delivery, recognized overnight courier or, within the United States, may also be
sent via certified mail, return receipt requested. All other notices may also be
sent by fax, confirmed by first class mail. All notices shall be deemed to have
been given and received on the earlier of actual delivery or three (3) days from
the date of postmark.

     Section 7.9 Nonassignability. Neither party may, directly or indirectly, in
whole or in part, whether by operation of law or otherwise, assign or transfer
this Agreement, without the other party's prior written consent, and any
attempted assignment, transfer or delegation without such prior written consent
shall be voidable at the sole option of such other party. Notwithstanding the
foregoing, each party (or its permitted successive assignees or transferees
hereunder) may assign or transfer this Agreement as a whole without consent to a
Person that succeeds to all or substantially all of the business or assets of
such party as long as such Person agrees to accept all the terms and conditions
set forth herein. Without limiting the foregoing, this Agreement will be binding
upon and inure to the benefit of the parties and their permitted successors and
assigns.

     Section 7.10 Severability. If any term or other provision of this Agreement
or the Exhibits attached hereto is determined by a court, administrative agency
or arbitrator to be invalid, illegal or incapable of being enforced by any rule
of law or public policy, all other conditions and provisions of this Agreement
shall nevertheless remain in full force and effect so long as the economic or
legal substance of the transactions contemplated hereby is not affected in any
manner materially adverse to either party. Upon such determination that any term
or other provision is invalid, illegal or incapable of being enforced, the
parties hereto shall negotiate in


                                      -8-
<PAGE>   12


good faith to modify this Agreement so as to effect the original intent of the
parties as closely as possible in an acceptable manner to the end that
transactions contemplated hereby are fulfilled to the fullest extent possible.

     Section 7.11 Failure or Indulgence Not Waiver; Remedies Cumulative. No
failure or delay on the part of either party hereto in the exercise of any right
hereunder shall impair such right or be construed to be a waiver of, or
acquiescence in, any breach of any representation, warranty or agreement herein,
nor shall any single or partial exercise of any such right preclude other or
further exercise thereof or of any other right. All rights and remedies existing
under this Agreement or the Exhibits attached hereto are cumulative to, and not
exclusive of, any rights or remedies otherwise available.

     Section 7.12 Amendment. No change or amendment will be made to this
Agreement or the Exhibits attached hereto except by an instrument in writing
signed on behalf of each of the parties to such agreement.

     Section 7.13 Counterparts. This Agreement, including the Ancillary
Agreements and the Exhibits and Schedules hereto and thereto and the other
documents referred to herein or therein, may be executed in counterparts, each
of which shall be deemed to be an original but all of which shall constitute one
and the same agreement.



                    [REST OF PAGE INTENTIONALLY LEFT BLANK.]


                                      -9-
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     WHEREFORE, the parties have signed this Master Confidential Disclosure
Agreement effective as of the date first set forth above.



MERCURY AIR GROUP, INC.,
a Delaware corporation


By:
   -----------------------------------------
Its:



MERCFUEL, INC.,
a Delaware corporation


By:
   -----------------------------------------
Its: