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                                                                    Exhibit 4.17

ING CAPITAL  Internationale Nederlanden (U.S.) Capital Corporation
______________________________________________________________________________
                               December 28, 1995
HarCor Energy Inc.
Five Post Oak Park, suite 2220
Houston, Texas 77027
Attention:   Mark G. Harrington
             Chairman and Chief Executive Officer

Gentlemen:

     This letter sets forth the terms and conditions of the agreement between
Internationale Nederlanden (U.S) Capital Corporation ("INCC") and HarCor Energy
Inc. ("HarCor") relating to the payment of certain fees and reimbursable costs
owed by HarCor to INCC in connection with the Amended and Restated Credit
Agreement entered into as of July 19, 1995 between INCC and HarCor (the "Credit
Agreement").

     By your execution of this letter agreement, it is agreed that payment of
the fees and reimbursable costs owed by HarCor to INCC in connection with the
Credit Agreement will be satisfied as follows:

     (1)  HarCor will:

          (i) pay to INCC, by wire transfer in immediately available funds, the
     amount of $137,654.71 ($37,654.71 of which is for reimbursement of the fees
     and expenses of counsel to INCC previously billed to HarCor in connection
     with the Credit Agreement, and at the request of INCC will be directly
     wired to INCC's Counsel); and

          (ii) deliver to INCC, 30,000 unregistered shares of HarCor Common
     Stock (the "Shares") which such Shares shall:

               (A) have been duly and validly issued by HarCor, fully paid and
     nonassessable and free from all taxes, liens and charges; and

               (B)  be entitled to "piggy-back registration rights" if the
     Company proposes to file a Registration Statement for its own account of
     its common equity securities (other than (i) a Registration Statement on
     Form S-4 or S-8, or (ii) a Registration Statement filed in connection with
     an exchange offer or offering of securities solely to the Company's
     existing security holders).  The Company would give INCC at least 30 days
     prior written notice of any filing and at the request of INCC would include
     the Shares in such registration, at the expense of the Company ("piggy-back
     registration rights"), subject to any limitations and priorities
     customarily set forth in similar registration rights granted by the
     Company.
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     (2) INCC will thereafter deliver to HarCor for cancellation: (i) that
     certain Warrant to purchase 76,000 shares of the common stock of HarCor at
     an exercise price of $5.50 with an expiration date of March 18, 1997; and
     (ii) that certain Warrant to purchase 50,000 shares of HarCor Common Stock
     with an exercise price of $4.75 and an expiration date of December 31,
     1999.


     HarCor also acknowledges and agrees that the provisions in the Credit
     Agreement requiring HarCor to reimburse INCC for all costs and expenses
     relating to such Credit Agreement (including reasonable fees and expenses
     of counsel in addition to those referred to in paragraph (1) and to
     indemnify INCC and its directors, officers, and employees for liabilities
     in connection therewith, shall be applicable to this letter agreement and
     the transactions contemplated hereby and shall survive the termination of
     this letter agreement.


     This agreement shall terminate and INCC's obligations hereunder shall be of
     no further force and effect if HarCor shall not have performed its
     obligations under this letter agreement on or before December 31, 1995.

     No waiver of any provision of the Credit Agreement or any other Loan
     Document executed in connection therewith shall be deemed to have occurred
     by execution of this letter agreement nor shall this letter be deemed to
     amend, alter, modify or impair the Credit Agreement or such other Loan
     Documents.  The terms and provisions of the Credit Agreement and all other
     Loan Documents executed in connection therewith are and shall remain in
     full force and effect and the same are hereby ratified and confirmed by the
     Borrower in all respects.

     This letter shall be governed by New York law.  This letter shall not be
     delivered to any other party.


     Please evidence your agreement to and acceptance of the foregoing by
     signing and returning to us the enclosed copy of this letter.

                              Yours truly,

                              Internationale Nederlanden  (U.S)
                              Capital Corporation

                              By: /s/ Trond O. Rokhold
                                 --------------------------------
                                  Trond O. Rokholt
                                    Vice President

AGREED TO AND ACCEPTED
as of December 28, 1995

HarCor Energy, Inc.
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By: /s/ Mark G. Harrington
   ------------------------------------
  Mark G. Harrington
  Chairman and Chief Executive Officer