AMENDMENT TO THE LIMITED PARTNERSHIP AGREEMENT
                                       OF
                             SHELL CO2 COMPANY, LTD.


This  Amendment to the Amended and  Restated  Limited  Partnership  Agreement of
Shell  CO2  Company  LTD,  is  hereby  made and  entered  into  this 30th day of
September, 1998.

                                   WITNESSETH:

      WHEREAS,  by  instrument  dated March 5, 1998,  Shell CO2 General  LLC, as
General  Partner,  and Shell  CO2 LLC and  Kinder  Morgan  CO2 LLC,  as  Limited
Partners,  joined  together  to form  Shell  CO2  Company,  LTD.,  as a  limited
partnership under the Revised Uniform Limited  Partnership Act as enacted in the
State of Texas.

      WHEREAS,  the  undersigned  General  Partner  and  Limited  Partners  have
consented to all the terms and  provisions of said Amended and Restated  Limited
Partnership  Agreement of Shell CO2 Company,  LTD.,  and have agreed to be bound
thereby.

      NOW,  THEREFORE,  pursuant  to  Article  VII  of the  Limited  Partnership
Agreement  of Shell CO2  Company,  LTD.,  and in  accordance  with  Section  8.1
thereof,  said  Amended and  Restated  Limited  Partnership  Agreement is hereby
amended as follows:

      The Partners agree to use and record the historical  financial book values
(as determined by applying generally accepted  accounting  principles) of assets
contributed  to Shell CO2 Company,  LTD. for financial  accounting and financial
statement purposes in accordance with Generally Accepted Accounting  Principles.
The historical  book values will be utilized for financial  accounting  purposes
notwithstanding  any other statement in the First Amended and Restated Agreement
of Limited Partnership of Shell CO2 Company,  LTD. This amendment does not amend
and or alter the agreed upon  initial  Gross Asset Value or fair market value of
initial Capital  Contributions  used to determine the Partners' capital accounts
for federal income tax purposes in Shell CO2 Company, LTD.


                                   /s/ M.G. Brookshier
                               ------------------------------------------
                                                      Shell CO2 LLC

                                   /s/ R.T. Bradley
                               ------------------------------------------
                                              Shell CO2 General LLC

                                   /s/ David G. Dehaemers, Jr.
                               ------------------------------------------
                                              Kinder Morgan CO2 LLC