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                        AMENDMENT TO EMPLOYMENT AGREEMENT

THIS AMENDMENT TO EMPLOYMENT AGREEMENT is entered into this 2nd day of June,
1999, between BASIN EXPLORATION, INC., a Delaware corporation (the
"Corporation"), and HOWARD L. BOIGON (the "Officer").

     The Corporation and the Officer have previously entered into a Change of
Control Employment Agreement dated as of October 13, 1995 (the "Employment
Agreement") and desire to amend the Employment Agreement to clarify certain
provisions regarding compensation payable to the Officer in the event of a
Change of Control as defined in the Employment Agreement.

     NOW, THEREFORE, in consideration of the premises and for good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties agree as follows:

         1. DEFINED TERMS. All terms used and not defined herein shall have
the meaning given them in the Employment Agreement.

         2. AMENDMENT OF SECTION 6(a). The last sentence of Section 6(a) of
the Employment Agreement is amended to read as follows:

     Any restrictions on restricted stock grants and performance share grants
     shall also be eliminated.

         3. AMENDMENT OF SECTION 9. Section 9 is amended to read as follows:

         LIMITATION ON AMOUNT OF PAYMENT.

          (a)  LIMITATION. Notwithstanding anything else in this Agreement,
               solely in the event of a termination by the Company without Cause
               or a termination by the Officer for Good Reason, and except as
               provided in subsection (i) below, the aggregate of the payments
               of benefits to which the Officer will be entitled under Section
               6(a) will be reduced to the extent necessary so that the Officer
               will not be liable for the federal excise tax levied on certain
               "excess parachute payments" under section 4999 of the Internal
               Revenue Code.

               (i)  The limitation of Section 9(a) will not apply if the
                    difference between (w) the present value of all payments to
                    which the Officer is entitled under paragraph 6(a)
                    determined without regard to Section 9(a) less (x) the
                    present value of all federal, state and other income and
                    excise taxes for which the Officer is liable as a result of
                    such payments exceeds the difference between (y) the present
                    value of all payments to which the Officer is entitled under
                    Section 6(a)

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                    calculated as if the limitation of Section 9(a)
                    applies less (z) the present value of all federal, state and
                    other income and excise taxes for which the Officer is
                    liable as a result of such reduced payments. Present values
                    will be determined using the interest rate specified in
                    section 280G of the Internal Revenue Code and will be the
                    present values as of the date on which the Officer's
                    employment terminates (unless it is necessary to use a
                    different date in order to avoid adverse consequences under
                    section 280G).

          (b)  DETERMINATION BY OFFICER. Whether payments to the Officer are to
               be reduced pursuant to Section 9(a), and the extent to which they
               are to be so reduced, will be determined by the Officer. The
               Officer may, at the expense of the Company, hire an accounting
               firm, law firm or employment consulting firm selected by the
               Officer to assist him in such determination. If a reduction is
               made pursuant to Section 9(a), the Officer will have the right to
               determine which payments and benefits will be reduced.

          (c)  ADDITIONAL BENEFIT. The Officer shall receive the benefit of any
               change made by the Company in the calculation or entitlement of
               severance compensation following a Change of Control for any
               other officer of the Company, such as an agreement by the Company
               to "gross up" the compensation paid to an officer by paying the
               excise tax imposed by Section 280G of the Internal Revenue Code .

         4. EFFECT OF AMENDMENT. As amended hereby, the Employment Agreement
remains in full force and effect.

     IN WITNESS WHEREOF, the parties have executed this Amendment to
Employment Agreement on the day and year first above entered.


                                       BASIN EXPLORATION, INC.


                                       By
                                         ----------------------------
                                         President


                                       -------------------------------
                                       HOWARD L. BOIGON