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                                                                    Exhibit 10.1



                               FIFTH AMENDMENT TO
                FIRST AMENDED AND RESTATED MANAGEMENT AGREEMENT
                      BETWEEN DEEPTECH INTERNATIONAL INC.
                       AND LEVIATHAN GAS PIPELINE COMPANY


   This Fifth Amendment dated as of July 1, 1997 (this "Amendment") has been
executed and delivered by the undersigned for the purpose of amending the First
Amended and Restated Management Agreement dated as of June 27, 1994 (the
"Agreement", as amended) between DeepTech International Inc. and Leviathan Gas
Pipeline Company.  Unless otherwise defined in the Amendment, all capitalized
terms herein shall have the meanings ascribed to them in the Agreement.

   WHEREAS, the parties deem it to be in their mutual best interests to amend
certain compensation and other provisions included in the Agreement.

   NOW, THEREFORE, the Parties hereby amend the Agreement as follows:

         1.      Amendment of Subsection 3.1.  Section 3.1 of the Agreement is
                 hereby amended by deleting it in its entirety and replacing it
                 with the following:

                 3.1      Fee.  Prior to July 1, 1994, the annual compensation
                          due  DII from LGPC for services provided pursuant to
                          this Agreement shall accrue in accordance with the
                          original terms and conditions of the Agreement prior
                          to any amendments.  On and as of July 1, 1994 through
                          and including October 31, 1995, the annual
                          compensation (prorated for any portion of a year) due
                          DII from LGPC for services provided pursuant to this
                          Agreement shall be (i) a base fee of $2,000,000.00
                          plus (ii) 40% of DII's Unreimbursed Overhead, if any.
                          On and as of November 1, 1995 through and including
                          June 30, 1996, the annual compensation (prorated for
                          any portion of a year) due DII from LGPC for services
                          provided pursuant to this Agreement shall be 45.3% of
                          DII's Overhead.  On and as of July 1, 1996 through
                          and including June 30, 1997, the annual compensation
                          due DII from LGPC for services provided pursuant to
                          this Agreement shall be 54% of DII's Overhead.  On
                          and as of July 1, 1997 through the term of this
                          Agreement, the annual compensation (prorated for any
                          portion of a year) due DII from LGPC for services
                          provided pursuant to this Agreement shall be 52% of
                          DII's Overhead.





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   LGPC shall also promptly reimburse DII with respect to amounts incurred for
the direct benefit of LGPC.

   IN WITNESS WHEREOF, the Parties have executed this Amendment effective as of
the date first set forth in the preamble.


DEEPTECH INTERNATIONAL INC.             LEVIATHAN GAS PIPELINE COMPANY
                               
                               
                               
By: /s/ Donald V. Weir                  By: /s/ Grant E. Sims                
   ------------------------                ----------------------------------
Donald V. Weir                             Grant E. Sims
Chief Financial Officer                    Chief Executive Officer