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                                                                    EXHIBIT 10.2


April 9, 2003

Joe Kimmel
Manager Marketing & Transportation
Shell Exploration & Production Company, and on behalf of all
Shell Producer Entities
200 North Dairy Ashford
Houston, TX  77079

RE:  Letter Agreement Concerning Sections 6.6 and 11.1 of the Sixth Amendment to
     the Conveyance of Gas Processing Rights effective March 1, 2003, between
     Enterprise Gas Processing, LLC, and Shell Oil Company and Other Shell
     Producer Entities

Dear Joe:

Enterprise Gas Processing, LLC ("Processor") and the undersigned Shell
Exploration & Production Company, Shell Oil Company, Shell Offshore Inc.
(including Shell Deepwater Development Inc. and Shell Deepwater Production Inc.,
which were merged into Shell Offshore Inc.), Shell Consolidated Energy Resources
Inc., Shell Land & Energy Company, Shell Frontier Oil & Gas Inc. and Shell Gulf
of Mexico Inc. (the foregoing Shell entities collectively herein "Producers")
are parties to that certain Sixth Amendment to the Conveyance of Gas Processing
Rights, effective as of March 1, 2003 (the "Conveyance Agreement").

This letter agreement ("Letter Agreement") sets forth the agreement between
Processor and Producers regarding Section 6.6 (Consideration Adjustment Outside
of Normal Operations) and its subparts ("Section 6.6") of the Conveyance
Agreement and regarding Section 11.1 (Mutual Agreement Not to Curtail or
Withhold) of the Conveyance Agreement. Capitalized terms used in this Letter
Agreement that are not defined herein shall have the same meaning ascribed to
such terms in the Conveyance Agreement.

In consideration of the premises, and for other good and valuable consideration,
the receipt and sufficiency of which is hereby acknowledged, the undersigned
parties agree as follows.

1.   For the five calendar year period beginning March 1, 2008 and ending
     February 28, 2013, and for each five calendar year period thereafter during
     the term of the Conveyance Agreement (i.e., March 1, 2013 through February
     28, 2018, etc.) (hereinafter a "Five Year Period"), Processor and Producers
     (all Producers collectively and not individually or less than all
     Producers; Processor and all Producers collectively each being referred to
     herein as a "Party") shall have the right to renegotiate with the other
     Party the provisions of Section 6.6 by delivering to the other Party
     written notice thereof ("Renegotiation Notice"). The Renegotiation Notice
     shall be delivered no more than 120 days nor less than 90


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     days prior to (i) March 1, 2008, for the initial Five Year Period and/or
     (ii) the date on which any subsequent Five Year Period commences (March 1
     of the first calendar year). Any Renegotiation Notice shall be provided in
     accordance with Section 18.6 of the Conveyance Agreement.

2.   If, following delivery of a timely Renegotiation Notice, a definitive
     agreement for a renegotiated Section 6.6 is reached and fully executed by
     Processor and all Producers prior to the date of commencement (March 1 of
     the first calendar year) of the applicable Five Year Period, the new
     provisions thereof shall be effective at and as of the commencement of the
     applicable Five Year Period.

3.   If, following delivery of a timely Renegotiation Notice, a definitive
     agreement for a renegotiated Section 6.6 is not reached and fully executed
     by Processor and all Producers prior to the date of commencement (March 1
     of the first calendar year) of the applicable Five Year Period, the whole
     of Section 6.6 and this Letter Agreement (including paragraph 4 herein
     pertaining to Section 11.1 of the Conveyance Agreement) shall terminate
     effective at and as of the commencement of the applicable Five Year Period.

4.   The Parties agree that, as used in Section 11.1 of the Conveyance
     Agreement, "good faith reason" shall not include economic hardships.

5.   If neither Party timely delivers a Renegotiation Notice with respect to a
     Five Year Period, Section 6.6 shall continue in full force and effect for
     such Five Year Period.

6.   The provisions of this Letter Agreement are personal to each Party and
     shall not be assigned by a Party except to an Affiliate of a Party. In any
     event, this Letter Agreement is not applicable to and shall be of no force
     or effect as to any assignees of a Dedicated Lease that is subject to the
     Conveyance Agreement.

7.   Nothing in this Letter Agreement, whether express or implied, is intended
     to confer any rights or remedies under or by reason of this Letter
     Agreement on any person other than the undersigned parties.

8.   Each Party agrees that this Letter Agreement and its provisions are
     confidential and shall not be disclosed by a Party, without the written
     consent of the other Party, to a third party (excluding Affiliates of a
     Party and the Party's and its Affiliates' employees, agents, contractors,
     attorneys, accountants, lenders, consultants or other advisors who have
     agreed to keep such terms confidential) except to the extent necessary to
     comply with any applicable law, order, regulation or exchange rule
     (including, without limitation, the rules of the Securities and Exchange
     Commission and the New York Stock Exchange).

9.   The Dispute Resolution provisions of the Conveyance Agreement, Sections
     16.1 through 16.4, inclusive, are incorporated by this reference as though
     fully set forth herein and shall apply to this Letter Agreement.


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10.  This Letter Agreement shall be governed by and enforced in accordance with
     the laws of the State of Louisiana without giving effect to its principles
     regarding conflicts of laws.

In witness whereof, the undersigned parties have caused this Letter Agreement,
effective March 1, 2003, to be executed by their duly authorized representative
on the dates indicated below.


PROCESSOR                               PRODUCER
ENTERPRISE GAS PROCESSING, LLC          SHELL OIL COMPANY


By:  /s/ W. Ordemann                    By:  /s/ B. K. Garrison
   ---------------------------             ---------------------------

Name: W. Ordemann                       Name: B. K. Garrison
Title: Sr. Vice President               Title: Attorney-in-Fact
Date: April 9, 2003                     Date: April 9, 2003


                                        SHELL OFFSHORE INC.

                                        By:  /s/ J. W. Kimmel
                                           ---------------------------
                                        Name: J. W. Kimmel
                                        Title: Attorney-in-Fact
                                        Date: April 9, 2003


                                        SHELL CONSOLIDATED ENERGY RESOURCES INC.

                                        By:  /s/ B. K. Garrison
                                           ---------------------------
                                        Name: B. K. Garrison
                                        Title: Attorney-in-Fact
                                        Date: April 9, 2003


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                                        SHELL LAND & ENERGY COMPANY

                                        By: /s/ B. K. Garrison
                                           ---------------------------
                                        Name: B. K. Garrison
                                        Title: Attorney-in-Fact
                                        Date: April 9, 2003


                                        SHELL FRONTIER OIL & GAS INC.

                                        By:  /s/ J. W. Kimmel
                                           ---------------------------
                                        Name: J. W. Kimmel
                                        Title: Attorney-in-Fact
                                        Date: April 9, 2003


                                        SHELL EXPLORATION & PRODUCTION COMPANY

                                        By:  /s/ R. M. Restucci
                                           ---------------------------
                                        Name: R. M. Restucci
                                        Title: President & CEO
                                        Date: April 9, 2003


                                        SHELL GULF OF MEXICO INC
                                        By:  /s/ J. W. Kimmel
                                           ---------------------------
                                        Name: J. W. Kimmel
                                        Title: Attorney-in-Fact
                                        Date: April 9, 2003


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