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                                                              EXHIBIT (c)(3)

                             STOCKHOLDER AGREEMENT



         Stockholder Agreement dated as of July 1, 1996, between AI Partners
L.P. ("Parent") and Kenneth J. Boutte ("Stockholder").

         WHEREAS, Stockholder desires that AMBAR, Inc., a Delaware corporation
(the "Company"), Parent and Purchaser, a Delaware corporation and wholly owned
subsidiary of Parent ("Purchaser"), enter into an Agreement and Plan of Merger
dated the date hereof (as the same may be amended or supplemented, the "Merger
Agreement") with respect to the merger of Purchaser with and into the Company
(the "Merger"); and

         WHEREAS, Stockholder is executing this Agreement as an inducement to
Parent to enter into and execute, and to cause Purchaser to enter into and
execute, the Merger Agreement;

         NOW, THEREFORE, in consideration of the execution and delivery by
Parent and Purchaser of the Merger Agreement and the mutual covenants,
conditions and agreements contained herein and therein, the parties agree as
follows:

         SECTION 1. Representations and Warranties.

         Stockholder represents and warrants to Parent as follows:

                  (a) Stockholder is the record and beneficial owner of 227,424
shares of Common Stock, par value $.01 per share, of the Company (the "Company
Common Stock" and such Stockholder's shares of Company Common Stock and any
shares of Company Common Stock acquired hereafter including upon the exercise of
outstanding options being referred to herein as "Shares"). Except for such
Shares, and options to purchase 5,000 Shares which are currently unexercisable,
Stockholder is not the record or beneficial owner of any shares of Company
Common Stock.

                  (b) This Agreement has been duly authorized, executed and
delivered by Stockholder and constitutes the legal, valid and binding obligation
of Stockholder, enforceable against Stockholder in accordance with its terms.
Neither the execution and delivery of this Agreement nor the consummation by
Stockholder of the transactions contemplated hereby will result in a violation
of, or a default under, or conflict with, any contract, trust, commitment,
agreement, understanding, arrangement or restriction of any kind to which
Stockholder is a party or bound or to which Stockholder's Shares are subject. If
Stockholder's Shares constitute community property, this Agreement has been duly
authorized, executed and delivered by, and constitutes a valid and binding
agreement of, Stockholder's spouse, enforceable against such person in
accordance with its terms. Consummation by Stockholder of the transactions
contemplated hereby will not violate, or require any consent, approval, or
notice under, any provision of any judgment, order, decree, statute,


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law, rule or regulation applicable to Stockholder or Stockholder's Shares,
except for any necessary filing under the Hart-Scott-Rodino Antitrust
Improvements Act of 1976.

                  (c) Stockholder's Shares and the certificates representing
such Shares are now and at all times during the term hereof will be held by
Stockholder, or by a nominee or custodian for the benefit of Stockholder, free
and clear of all liens, claims, security interests, proxies, voting trusts or
agreements, understandings or arrangements or any other encumbrances whatsoever,
except for any such encumbrances or proxies arising hereunder.

                  (d) No broker, investment banker, financial adviser or other
person is entitled to any broker's, finder's, financial adviser's or other
similar fee or commission in connection with the transactions contemplated
hereby based upon arrangements made by or on behalf of Stockholder.

                  (e) Stockholder understands and acknowledges that Parent is
entering into, and causing Purchaser to enter into, the Merger Agreement in
reliance upon Stockholder's execution and delivery of this Agreement.
Stockholder acknowledges that the irrevocable proxy set forth in Section 4 is
granted in consideration for the execution and delivery of the Merger Agreement
by Parent and Purchaser.

         SECTION 2. Purchase and Sale of Shares.

         Stockholder hereby agrees to sell to Purchaser, and Purchaser hereby
agrees to purchase, all Shares at a price per share equal to the price paid for
Company Common Stock in the Offer; provided that such obligation to sell and
such obligation to purchase is subject to Purchaser having accepted shares for
payment under the Offer. Stockholder may tender Shares into the Offer and
Purchaser may direct that Stockholder tender such Shares. Any Shares not
purchased in the Offer will be purchased at the same time as payment is made
under the Offer.

         SECTION 3. Covenants.

         Stockholder agrees with, and covenants to, Parent as follows:

                  (a) Stockholder shall not, except as contemplated by the terms
of this Agreement, (i) transfer (which term shall include, without limitation,
for the purposes of this Agreement, any sale, gift, pledge or other
disposition), or consent to any transfer of, any or all of Stockholder's Shares
or any interest therein, (ii) enter into any contract, option or other agreement
of understanding with respect to any transfer of any or all of such Shares or
any interest therein, (iii) grant any proxy, power-of-attorney or other
authorization in or with respect to such Shares, (iv) deposit such Shares into a
voting trust or enter into a voting agreement or arrangement with respect to
such Shares or (v) take any other action that would in any way restrict, limit
or interfere with the performance of its obligations hereunder or the
transactions contemplated hereby.


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                  (b) Subject to Section 8, Stockholder shall not, nor shall it
permit any investment banker, attorney or other adviser or representative of
Stockholder to, directly or indirectly, (i) solicit, initiate or encourage the
submission of, any takeover proposal or (ii) participate in any discussions or
negotiations regarding, or furnish to any person any information with respect
to, or take any other action to facilitate any inquiries or the making of any
proposal that constitutes, or may reasonably be expected to lead to, any
takeover proposal. Without limiting the foregoing, it is understood that any
violation of the restrictions set forth in the preceding sentence by an
investment banker, attorney or other adviser or representative of Stockholder,
whether or not such person is purporting to act on behalf of such Stockholder or
otherwise, shall be deemed to be a violation of this Section 3(b) by
Stockholder.

                  (c) Stockholder shall not take any action which would
restrict, limit or frustrate in any way the transactions contemplated by this
Agreement.

                  (d) Subject to Section 7 hereof, at any meeting of the
Company's Stockholders or at any adjournment thereof or in any other
circumstances upon which their vote, consent or other approval is sought,
Stockholder shall vote (or cause to be voted) Stockholder's Shares against (i)
any merger agreement or merger (other than the Merger Agreement and the Merger),
consolidation, combination, sale of substantial assets, reorganization, joint
venture, recapitalization, dissolution, liquidation or winding up of or by the
Company and (ii) any amendment of the Company's Certificate of Incorporation or
By-laws or other proposal or transaction involving the Company or any of its
subsidiaries which amendment or other proposal or transaction would in any
manner impede, frustrate, prevent or nullify, or result in a breach of any
covenant, representation or warranty or any other obligation or agreement of the
Company under or with respect to, the Offer, the Merger, the Merger Agreement or
any of the other transactions contemplated by the Merger Agreement (each of the
foregoing in clause (i) or (ii) above, a "Competing Transaction").

         SECTION 4. Grant of Irrevocable Proxy: Appointment of Proxy.

                  (a) Stockholder hereby irrevocably grants to, and appoints,
Harold W. Pote and Robert F. Semmens, in their respective capacities as officers
of Parent, and any individual who shall hereafter succeed to any such office of
Parent, and each of them individually, Stockholder's proxy and attorney-in-fact
(with full power of substitution), for and in the name, place and stead of
Stockholder, to vote Stockholder's Shares, or grant a consent or approval in
respect of Shares against any Competing Transaction.

                  (b) Stockholder represents that any proxies heretofore given
in respect of Stockholder's Shares are not irrevocable, and that any such
proxies are hereby revoked.

                  (c) Stockholder hereby affirms that the irrevocable proxy set
forth in this Section 4 is given in connection with the execution of the Merger
Agreement, and that such irrevocable proxy is given to secure the performance of
the duties of Stockholder under this Agreement. Stockholder hereby further
affirms that the irrevocable proxy is coupled with an interest and may 


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under no circumstances be revoked. Such Stockholder hereby ratifies and confirms
all that such irrevocable proxy may lawfully do or cause to be done by virtue
hereof. Such irrevocable proxy is executed and intended to be irrevocable in
accordance with the provision of Section 212(e) of the Delaware General
Corporation Law (the "DGCL").

         SECTION 5. Certain Events.

         Stockholder agrees that this Agreement and the obligations hereunder
shall attach to Stockholder's Shares and shall be binding upon any person or
entity to which legal or beneficial ownership of such Shares shall pass, whether
by operation of law or otherwise, including without limitation Stockholder's
heirs, guardians, administrators or successors. In the event of any stock split,
stock dividend, merger, reorganization, recapitalization or other change in the
capital structure of the Company affecting the Company Common Stock, or the
acquisition of additional shares of Company Common Stock or other voting
securities of the Company by Stockholder, this Agreement and the obligations
hereunder shall attach to any additional shares of Company Common Stock or other
voting securities of the Company issued to or acquired by Stockholder.

         SECTION 6. Legend.

         Stockholder agrees that Stockholder will deliver to the Company, within
5 business days after the date hereof, any and all certificates representing
Stockholder's Shares in order that the Company may inscribe upon such
certificates the following legend: "The shares of Common Stock, $.01 par value,
of AMBAR, Inc. represented by this certificate are subject to a Stockholder
Agreement dated as of July 1, 1996, and may not be sold or otherwise
transferred, except in accordance therewith. Copies of such Agreement may be
obtained at the principal executive offices of AMBAR, Inc."

         SECTION 7. Voidability.

         If prior to the execution hereof, the Board of Directors of the Company
shall not have duly and validly authorized and approved by all necessary
corporate action, this Agreement, the Merger Agreement and the transactions
contemplated hereby and thereby, or if, subsequent to any such approval or
authorization, the Board of Directors withdraws any such authorization and
approval so that by the execution and delivery hereof Parent or Purchaser would
become, or could reasonably be expected to become an "interested stockholder"
with whom the Company would be prevented for any period pursuant to Section 203
of the DGCL or the Certificate Incorporation of the Company from engaging in any
"business combination" (as such terms are defined in Section 203 of the DGCL)
then this Agreement shall be void and unenforceable until such time as such
authorization and approval shall have been duly and validly obtained.



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         SECTION 8. Stockholder Capacity.

         By executing this Agreement Stockholder makes no agreement or
understanding herein in his capacity as a director and officer of the Company.
Stockholder signs solely in his capacity as the record holder and beneficial
owner of Stockholder's Shares and nothing herein shall limit or affect any
actions taken by Stockholder in his capacity as an officer or director of the
Company to the extent specifically permitted by the Merger Agreement. No action
taken by Stockholder solely in his capacity as an officer or director of the
Company shall be deemed to be a breach of this
Agreement; provided, however, that no such action by Stockholder shall excuse
Stockholder from his obligations under Section 2 of this Agreement.

         SECTION 9. Further Assurances.

         Stockholder shall, upon request of Parent, execute and deliver any
additional documents and take such further actions as may reasonably be deemed
by Parent to be necessary or desirable to carry out the provisions hereof and to
vest the power to vote Stockholder's Shares as contemplated by Section 4 in
Parent and the other irrevocable proxies described therein.

         SECTION 10. Termination.

         This Agreement, and all rights and obligations of the parties
hereunder, shall terminate upon the first to occur of (i) the Effective Time of
the Merger or (ii) the termination of the Merger Agreement pursuant to Section
8.1, other than Section 8.1(j), thereof.

         SECTION 11. Miscellaneous.

                  (a) Capitalized terms used and not otherwise defined in this
Agreement shall have the respective meanings assigned such terms in the Merger
Agreement.

                  (b) All notices, requests, claims, demands and other
communications under this Agreement shall be in writing and shall be deemed
given if delivered personally or sent by overnight courier (providing proof of
delivery) to the parties at the following addresses (or at such other address
for a party as shall be specified by like notice): (i) if to Parent, to the
address set forth in Section 9.5 of the Merger Agreement; and (ii) if to
Stockholder, to Kenneth J. Boutte, c/o AMBAR, Inc., The AMBAR Building, 221 Rue
de Jean, Suite 300, Lafayette, LA 70508, or such other address as may be
specified in writing by Stockholder.

                  (c) The headings contained in this Agreement are for reference
purposes only and shall not affect in any way the meaning or interpretation of
this Agreement.

                  (d) This Agreement may be executed in counterparts, each of
which shall be considered one and the same agreement and shall become effective
as to any Stockholder when one 


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or more counterparts have been signed by each of Parent and Stockholder and
delivered to Parent and Stockholder.

                  (e) This Agreement (including the documents and instruments
referred to herein) constitutes the entire agreement, and supersedes all prior
agreements and understandings, both written and oral, among the parties with
respect to the subject matter hereof.

                  (f) This Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware, regardless of the laws that
might otherwise govern under applicable principles of conflicts of laws thereof.

                  (g) Neither this Agreement nor any of the rights, interests or
obligations under this Agreement shall be assigned, in whole or in part, by
operation of law or otherwise, by any of the parties without the prior written
consent of the other parties, except by laws of descent, provided that Parent
may assign any of its rights and obligations to any affiliate (as defined in
Rule 12b-2 under the Exchange Act) of Parent if such affiliate expressly assumes
in writing the obligations of Parent under this Agreement, but no such
assignment shall relieve Parent of its obligations hereunder.

                  (h) If any term, provision, covenant or restriction herein, or
the application thereof to any circumstance, shall, to any extent, be held by a
court of competent jurisdiction to be invalid, void or unenforceable, the
remainder of the terms, provisions, covenants and restrictions herein and the
application thereof to any other circumstances, shall remain in full force and
effect, shall not in any way be affected, impaired or invalidated, and shall be
enforced to the fullest extent permitted by law.

                  (i) Stockholder agrees that irreparable damage would occur and
that Parent would not have any adequate remedy at law in the event that any of
the provisions of this Agreement were not performed in accordance with their
specific terms or were otherwise breached. It is accordingly agreed that Parent
shall be entitled to an injunction or injunctions to prevent breaches by any
Stockholder of this Agreement and to enforce specifically the terms and
provisions of this Agreement in any court of the United States located in the
State of Delaware or in Delaware state court, this being in addition to any
other remedy to which they are entitled at law or in equity. In addition, each
of the parties hereto (i) consents to submit such party to the personal
jurisdiction of any Federal court located in the State of Delaware or any
Delaware state court in the event any dispute arises out of this Agreement or
any of the transactions contemplated hereby, (ii) agrees that such party will
not attempt to deny or defeat such personal jurisdiction by motion or other
request for leave from any such court and (iii) agrees that such party will not
bring any action relating to this Agreement of any of the transactions
contemplated hereby in any court other than a Federal court sitting in the State
of Delaware or a Delaware state court.

                  (j) No amendment, modification or waiver in respect of this
Agreement shall be effective against any party unless it shall be in writing and
signed by such party.


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         IN WITNESS WHEREOF, each of the parties has caused this Agreement to be
executed on its behalf by its officers thereunto duly authorized, all at or on
the day and year first above written.


Attest:  /s/ Stacey W. Goff              /s/ Kenneth J. Boutte
         ------------------------------  --------------------------------------
         Name: STACEY W. GOFF            KENNETH J. BOUTTE
         Title:

                                         AI PARTNERS L.P.

                                         By  AI-GP L.L.C., general partner

                                         By  Energy Fund GP, Inc., member

Attest:  /s/ Stacey W. Goff              By  /s/ Robert F. Semmens
         ------------------------------      ---------------------------------
         Name: STACEY W. GOFF                Name: ROBERT F. SEMMENS
         Title:                              Title: Managing Director


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