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                                                                  Exhibit 10.26



                          TERMINAL SERVICES AGREEMENT

     This Terminal Services Agreement (this "Agreement") dated January 14, 2000,
is between Millennium Terminal Company, L.P., a Texas limited partnership
("Millennium Terminal Company"), and Clark Refining & Marketing, Inc., a
Delaware corporation ("Clark").

                                  Background

1.    Millennium Pipeline Company, L.P. ("Millennium Pipeline Company"), owns
      and operates a common carrier pipeline (the "Pipeline") capable of
      transporting crude oil or other mutually agreeable, merchantable liquid
      hydrocarbons with the characteristics set forth in Annex A attachment
      hereto ("Produce") from a point near Beaumont, Texas to a point near
      Longview, Texas.

2.    In connection with the operation of the Pipeline, Millennium Terminal
      Company will provide - through an agreement with Oiltanking Beaumont,
      L.P. ("Oiltanking") - approximately 1,100,000 barrels of shell capacity
      (yielding approximately 1,040,000 barrels of working capacity) of
      storage (the "Storage Facility") at Oiltanking's off-loading and storage
      facility in Beaumont, Texas.

3.    Clark desires to deliver Product to Ole Storage Facility for
      redelivery into and transportation on the Pipeline.

4.    Millennium Terminal Company is willing to receive Product into storage
      for redelivery into and transportation on the Pipeline subject to the
      terms and conditions set forth in this Agreement.

                                   Agreement

Section 1.  Term of Agreement; Renewal.

      1.1   Initial Term. The initial term of this Agreement (the "Initial
            Term") will be for 5 Contract Years - beginning of the
            Commencement Date (defined below) and continuing through the end
            of the fifth Contract Year. As used in this Agreement,
            "Commencement Date" means the first day of the first month
            following the month in which the later of the following events
            occurs:

            (a)   Millennium Terminal Company executes a definitive agreement
                  with Oiltanking in connection with the Storage Facility; and

            (b)   all capital projects necessary to render the Pipeline
                  operational are complete to the degree required to place the
                  Pipeline into service on the Commencement Date.


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            Millennium Terminal Company will endeavor to provide Clark with as
            much written notice of the Commencement Date as possible; however,
            the obligations of Clark and Millennium Terminal Company will
            commence on the Commencement Date without regard to the length of
            such notice. Millennium Terminal Company anticipates that the
            Commencement Date will occur on or about April 1, 2000; this
            Agreement will terminate, however -- and the parties respective
            obligations will thereafter be excused - if the Commencement Date
            does not occur on or before October 1, 2000.

      1.2   Renewal; Termination.

            (a)   Unless terminated under Section 1.2(b) of this Agreement,
                  the term of the Agreement will be automatically renewed and
                  extended - without the taking of any additional action by
                  any party - for consecutive 1-year periods (each a "Renewal
                  Term"). The Initial Terms are collectively referred together
                  with all Renewal Terms throughout this Agreement as the
                  "Term."

            (b)   Either party may terminate this Agreement effective as of
                  the end of the Initial Term or any Renewal Term by
                  delivering to the other party a written notice of its
                  election to terminate at least 6 months prior to the
                  effective date of the termination.

            (c)   Either party may terminate this Agreement if the Incentive
                  Rate Contract between Clark and Millennium Pipeline Company
                  is terminated.

Section 2   Delivery Obligations; Deficiency Payments; Conditional Rate

      2.1   Delivery Obligations. Throughout the Term of this Agreement, Clark
            will deliver to the Storage Facility a minimum annual volume (the
            "Minimum Annual Volume") equal to 50,000 barrels of Product per
            day during each Contract Year. "Contract Year" means any calendar
            year-beginning on January 1 and ending on December 31 - or, if the
            Pipeline is not in service on January 1, 2000, any twelve-month
            period beginning on the date the Pipeline is first available for
            service or the anniversary date thereof. During each Contract
            Year, Clark will use reasonable efforts to schedule all deliveries
            of Product to Millennium Terminal Company during a given month
            ratably throughout that month.

      2.2   Allocation of Capacity. Throughout the Term of this Agreement,
            Millennium will provide Clark with sufficient storage capacity at
            the Storage Facility to enable Clark to meet the Minimum Annual
            Volume required by this Agreement.

      2.3   Deficiencies. If the total volume of Product delivered by Clark to
            the Storage Facility during any Contract Year (the "Contract Year
            Volume") is less than the Minimum Annual Volume, Clark will pay to
            Millennium Terminal Company an amount (a "Deficiency Payment")
            equal to the product of (i) an amount equal to the Minimum


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            Annual Volume minus the Contract Year Volume multiplied by (ii) the
            Terminal Rate (as defined in Section 3 of this Agreement).

      2.4   Conditional Rate. The applicability of the Terminal Rate described
            in Section 3.1 of this Agreement is expressly conditioned upon
            Clark's agreement to fulfill its obligations under this Section 2
            - including, without limitation, Clark's obligation to deliver to
            Millennium Terminal Company a Minimum Annual Volume equal to
            50,000 barrels of Product per day during each Contract Year and
            the redelivery of a like volume of Product to the Pipeline.

Section 3.  Rates

      3.1   Terminal Rate. Subject to the provisions of Section 12 of the
            General Terms and Conditions attached hereto as Annex A,
            throughout the Terms of this Agreement the rate (the "Terminal
            Rate") applicable to each barrel of Product delivered by Clark to
            Millennium Terminal Company and redelivered to the Pipeline (the
            "Monthly Delivered Volume") is thirteen cents ($0.130) per net
            barrel.

      3.2   Alternate Connecting Carrier Rate. Clark may, following receipt of
            the written consent of Millennium Terminal Company, deliver
            barrels of Product to Millennium Terminal Company for redelivery
            to any connecting carrier, pipeline or terminal other than the
            Pipeline (each an "Alternate Connecting Carrier") at a rate to be
            mutually agreed upon by Clark and Millennium Terminal Company from
            time-to-time; provided, however, that any barrels of Product
            delivered to Millennium Terminal Company pursuant to this Section
            3.2 will not count toward the Minimum Annual Volume.

      3.3   Long-Term Storage Rate. Clark may, following receipt of the
            written consent of Millennium Terminal Company and subject to the
            availability of shell capacity at the Storage Facility, elect to
            store barrels (collectively, the "Long-Term Storage Volume") of
            Product at the Storage Facility at a rate (the "Long Term Storage
            Rate") to be mutually agreed upon by Clark and Millennium Terminal
            Company from time-to-time. The Long-Term Storage Rate will be
            assessed (i) on all barrels of shell capacity utilized to store
            the Long-Term Storage Volume and (ii) for each 30-day period or
            portion thereof during which the Long-Term, Storage Volume remains
            at the Storage Facility; provided, however, that the first such
            30-day period will not begin until the 16th day following the date
            the Long-Term Storage Volume is delivered to the Storage Facility.
            Payment of the Long-Term Storage Rate will not affect Clark's
            obligation to pay to Millennium Terminal Company the applicable
            rate when all or any portion of the Long-Term Storage Volume is
            redelivered from the Storage Facility to the Pipeline or an
            Alternate Connecting Carrier.

Section 4.  Monthly Billing; Deficiency Payments

      4.1   Monthly Billing. Throughout the Term of this Agreement, Millennium
            Terminal


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            Company will invoice Clark monthly based on the volume of Product
            delivered from the Storage Facility. The total amount reflected on
            the monthly invoice will be due and payable within 10 days of the
            date of such invoice. The monthly invoice will set forth:

            (a)   the Monthly Delivered Volume -- including, without
                  limitation, any barrels withdrawn from the Long-Term Storage
                  Volume and redelivered to the Pipeline - as measured by a
                  custody transfer meter (the "Out-Bound Meter") located
                  between the Storage Facility and the origin of the Pipeline;

            (b)   the volume of Product, if any, delivered to an Alternate
                  Connecting Carrier as measured by a mutually agreeable
                  measurement device located at the custody transfer point of
                  the Alternate Connecting Carrier;

            (c)   the Long-Term Storage Volume, if any, based upon the amount
                  of shell capacity utilized; and

            (d)   the rate applicable to each such volume as set forth in
                  Section 3 above.

      4.2   Deficiency Payments. Millennium Terminal Company will invoice
            Clark during the first month of each Contract Year for any
            Deficiency Payment due for the immediately previous Contract Year.
            The amount of any such Deficiency Payment will be due and payable
            within 30 days of the date of such invoice.

      4.3   Late Payments. Any amount invoiced to Clark and not paid within
            the time periods set forth in Sections 4.1 and 4.2 above will
            accrue interest at the Default Rate from the date such amount is
            due until the date such amount is paid. As used in this Agreement,
            "Default Rate" means an interest rate equal to the lesser of (a)
            two percent (2.0%) plus the "Prime Rate" published in the Wall
            Street Journal on the date such amount is due and (b) the maximum
            rate allowable under applicable law.

Section 5.  Events of Default.

      5.1   Clark Defaults. If, at any time during the Term of this Agreement,
            one or more of the following events occurs:

            (a)   Clark fails to pay promptly any amounts owed to Millennium
                  Terminal Company under this Agreement;


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            (b)   Clark (i) becomes insolvent (which term is defined for
                  purposes hereof as failure to meet its obligations as the same
                  fall due); (ii) files a voluntary petition in bankruptcy,
                  reorganization, receivership or arrangement; (iii) files an
                  answer admitting any material allegation of any insolvency
                  petition filed pursuant to any insolvency act, federal or
                  state; (iv) makes an assignment for the benefit of any
                  creditor; (v) applies for, consents to, or suffers the
                  appointment of a receiver or trustee for any part of its
                  property or assets; or (vi) fails to satisfy or to appeal from
                  any material judgment or attachment within thirty (30) days
                  from the date of entry; or

            (c)   Clark violates or otherwise fails to substantially comply
                  with any material provision of this Agreement, without
                  regard to whether such violation or failure to comply is
                  specified as an event of default within this Section 5.1;
                  provided, however, that no act or omission by Clark will
                  constitute an event of default under this Section 5.1(c)
                  unless Clark fails to cure such violation or compliance
                  failure within 30 days after receiving notice of same from
                  Millennium Terminal Company;

            then  (i) Clark will be deemed for all purposes to be in default of
            this Agreement, (ii) Millennium Terminal Company will have good
            cause to cancel this Agreement and will be afforded all remedies
            provided under law, whether at law or in equity and (iii) the total
            amount of Clark's obligations under this Agreement will, at the
            option of Millennium Terminal Company, accelerate and become
            immediately due and payable.

      5.2   Millennium Terminal Company Defaults. If, at any time during the
            Term of this Agreement, Millennium Terminal Company violates or
            otherwise fails to substantially comply with any material
            provision of this Agreement, then (a) Millennium Terminal Company
            will be deemed for all purposes to be in default of this Agreement
            and (b) Clark will have good cause to cancel this Agreement and
            will be afforded all remedies provided under law, whether at law
            or in equity; provided, however, that no act or omission by
            Millennium Terminal Company will constitute an event of default
            under this Section 5.2 unless Millennium Terminal Company fails to
            cure such violation or compliance failure within 30 days after
            receiving notice of same from Clark.

Section 6.  Representations and Warranties.

      6.1   Clark represents and warrants to Millennium Terminal Company that

            (a)   it is a corporation duly organized and validly existing and
                  in good standing under the laws of the state of its
                  incorporation and has all requisite corporate power and
                  authority to enter this Agreement and to carry out the terms
                  and provisions hereof;


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            (b)   there is no action, proceeding, or investigation pending or
                  threatened so far as Clark is advised, and no term or
                  provisions of any charter, by-law, mortgage, indenture,
                  contract, agreement, instrument, judgment, decree, order,
                  statute, rule or regulation, which in any way prevents or
                  interferes with or adversely affects the entering into it, or
                  the carrying out of any of the terms or provisions of this
                  Agreement; and

            (c)   No approval of any governmental body is required for
                  carrying out this Agreement.

      6.2   Millennium represents and warrants to Clark that:

            (a)   is a limited partnership duly organized and validly existing
                  and in good standing under the laws of the state of its
                  formation and has all requisite power and authority to enter
                  this Agreement and to carry out the terms and provisions
                  hereof;

            (b)   there is no action, proceeding or investigation pending or
                  threatened so far as Millennium is advised, and no term or
                  provisions of any charter, by-law, mortgage, indenture,
                  contract, agreement, instrument, judgment, decree, order,
                  statute, rule or regulation, which in any way prevents or
                  interferes with or adversely affects the entering into it,
                  or the carrying out of any of the terms or provisions of
                  this Agreement; and

            (c)   No approval of any governmental body is required for
                  carrying out this Agreement.

Section 7.  Force Majeure. If, by reason of Force Majeure, either
            Millennium Terminal Company or Clark is rendered unable, wholly or
            in part, to carry out its obligations under this Agreement- other
            than its obligation to pay any amount of money due and owning
            under the terms of this Agreement-and, if the party so prevented
            from performing (the "Affected Party") gives notice and reasonably
            full particulars of such Force Majeure in writing or by telegraph
            to the other party within 24 hours after the occurrence of the
            event relied on, the Affected Party will be excused-to the extent
            its performance is affected by the Force Majeure-during the
            continuation of the event relied on; provided, however, that the
            Affected Party shall use reasonable efforts to cure the Force
            Majeure event as soon as possible; but provided further that
            settlement of labor disputes will be strictly within the
            discretion of the Affected Party. As used in this Section 7,
            "Force Majeure" includes, without limitation, acts of God; acts of
            a public enemy; fires; compliance with any court order, law,
            regulation or ordinance of any governmental authority having
            jurisdiction over the Affected Party; civil disturbances;
            shutdowns for purposes of necessary repair, relocation or
            construction of Pipeline or the Storage Facility; breakage or
            accidental damage to any pipe, machinery or equipment comprising
            the Pipeline, the cargo ship transporting Clark's Product to the
            Storage Facility or the Storage Facility; the


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            necessity for testing (as required by any governmental authority
            or as deemed necessary by Millennium Terminal Company for the safe
            operation of the Pipeline or the Storage Facility); the necessity
            of making repairs or alterations to any pipe, machinery or
            equipment comprising the Pipeline or the Storage Facility;
            inability of either party to obtain necessary material, supplies
            or permits, or labor to perform or comply with any obligation or
            condition of this Agreement; inability to obtain or retain
            rights-of-way; and any other cause, whether of a kind recited
            herein or not, that is not reasonably within the control of the
            Affected Party.

Section 8.  Miscellaneous.

      8.1   Loss Allowance. Millennium Terminal Company will collect from
            Clark a loss allowance equal to one-tenth of one percent (0.1%) of
            all barrels of Product delivered to the Storage Facility through a
            custody transfer meter (the "In-Bound Meter") located between the
            off-loading dock and the tank farm at the Storage Facility as an
            allowance (the "Loss Allowance") for losses or gains of Product,
            including shrinkage, metering inaccuracies, evaporation and
            interface losses.

      8.2   Prorationing. If Millennium Terminal Company is required to
            prorate one or more shipments of Product ("Prorated Barrels")
            delivered to the Storage Facility by Clark for transportation on
            the Pipeline, the Minimum Annual Volume of Product Clark is
            obligated to deliver will be proportionately reduced to reflect
            the effect of such prorationing.

      8.3   Notices. Except as otherwise provided herein, any notice required
            to be given under any provision of this Agreement must be in
            writing and directed to:

                Millennium      Millennium Terminal Company, L.P.
                                c/o Equilon Pipeline Company LLC
                                Two Shell Plaza
                                P.O. Box, 2648
                                Houston, Texas 77252-2648
                                Attn:  General Manager, Joint Ventures
                                Telephone:  (713) 241-3154
                                Fax:  (713) 241-1124

                                With a copy to:

                                Millennium Terminal Company, L.P.
                                c/o Black Hills Millennium Terminal, Inc.
                                4669 Southwest Freeway, Suite 400
                                Houston, Texas 77027
                                Attn:  Scott E. Bormaster, Executive Vice
                                       President
                                Telephone:  (713) 942-0595
                                Fax:  (713) 942-7915


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                                and

                Clark           Clark Refining & Marketing, Inc.
                                8182 Maryland Avenue
                                6th Floor
                                Clayton, Missouri 63105
                                Attn: John Overbey, Vice President
                                Telephone: (314) 854-1405
                                Fax: (314) 854-9635

                                With a copy to:

                                Clark Refining & Marketing, Inc.
                                8182 Maryland Avenue
                                Clayton, Missouri 63105
                                Attn: Legal Department
                                Telephone: (314) 854-9666
                                Fax: (314) 854-1455

            All notices will be deemed received by the addressee upon the
            earlier of (i) actual receipt by the person or persons to whom the
            notice is directed (including the receipt of a fax confirmation by
            the sender of the notice) and (ii) 3 days following the deposit of
            a properly addressed notice in the United States mail, postage
            prepaid.

      8.4   Consent to Assignment. Either party to this Agreement may assign
            all or any portion of its interest in this Agreement to any
            financially and operationally capable third-party; no such
            assignment, however, will relieve the assignor from any portion of
            its obligations under this Agreement. Nothing in this Section 8.4
            will be construed as prohibiting any party from pledging or
            mortgaging its rights under this Agreement to secure any
            indebtedness.

      8.5   Choice of Law. Except to the extent that the general maritime laws
            of the United States of America may be applicable, this Agreement
            is governed by and the terms of this Agreement are to be
            construed, enforced and performed in accordance with the laws of
            the State of Texas without regard to the principles of conflicts
            of law.

      8.6   Captions. The captions identifying the sections and subsections of
            this Agreement are for convenience only and are not intended by
            the parties to affect the meaning or interpretation of the
            provisions of this Agreement.

      8.7   Governmental Regulation. This Agreement is subject to all present
            and future valid laws, rules, regulations and lawful orders
            (collectively, the "Legal Requirements") of all governmental
            authorities now or hereafter having jurisdiction over the Storage
            Facility or the Pipleline. If any Legal Requirement is imposed -
            or if any existing

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            Legal Requirement is amended-that renders Millennium Terminal
            Company or Clark unable to lawfully fulfill its obligations under
            this Agreement (other than to pay sums of money due and owing at
            the time such Legal Requirement is imposed or amended), then this
            Agreement will be deemed reformed to conform to the then existing
            Legal Requirements.

      8.8   Amendment. This Agreement may be amended only by a written
            agreement executed by Millennium Terminal Company and Clark.

      8.9   Counterparts. The parties may execute this Agreement in two or
            more counterparts which shall, in the aggregate, constitute a
            single document.

      8.10  Severability. If any provision of this Agreement is determined to
            be invalid or unenforceable to any extent, the remaining
            provisions of this Agreement will remain in effect and will be
            enforced to the maximum extent permitted by law.

      8.11  Entire Agreement. This Agreement-including the General Terms and
            Conditions attached to this Agreement as Annex A and made a part
            of this Agreement for all purposes-constitutes the entire
            agreement between Millennium Terminal Company and Clark with
            respect to the matters addressed herein, and this Agreement
            supersedes any prior understanding or other written or oral
            agreements related to these matters. In the event that there is a
            conflict between the provisions of this Agreement and Annex A, the
            terms of this Agreement shall prevail. Throughout attached Annex
            A, Millennium Terminal Company is referred to as "Millennium," and
            Clark is referred to as Shipper.

                        [SIGNATURES APPEAR ON THE FOLLOWING PAGE]


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EXECUTED as of the date first set forth above.

                                      CLARK REFINING & MARKETING, INC.
                                      A Delaware corporation

                                      By: /s/ John Overbey
                                         ------------------------------------
                                      Printed Name: John Overbey
                                                   --------------------------
                                      Title: Vice President, Crude Oil Supply
                                            ---------------------------------
                                      MILLENIUM TERMINAL COMPANY, L.P.
                                      A Texas limited partnership

                                      By: Equilon Pipeline Company LLC,
                                          a General Partner

                                      By: /s/ Bernie Lednicky
                                         ------------------------------------
                                      Printed Name: Bernie Lednicky
                                                   --------------------------
                                      Title: Director, Joint Ventures
                                            ---------------------------------
                                      By: Black Hills Millennium Terminal, Inc.,
                                          a General Partner

                                      By: /s/ Scott E. Bormaster
                                         ------------------------------------
                                      Printed Name: Scott E. Bormaster
                                                   --------------------------
                                      Title: Executive Vice President
                                            ---------------------------------






              THIS IS THE SIGNATURE PAGE TO THE TERMINAL SERVICES AGREEMENT


<PAGE>


                                    ANNEX A

                         General Terms and Conditions

Section 1   Quality and Quantity.

      1.1   Acceptance of Storage Facility. It is agreed that Shipper is
            familiar in all respects with the Storage Facility and, in
            particular, with Oiltanking's marine facilities and pipeline
            systems to the extent they are to be provided under this
            Agreement. Before Millennium's initial receipt of Product (as
            defined in Section 3.1 of these General Terms and Conditions) from
            any Shipper, Shipper will have a representative inspect and accept
            the Storage Facility as clean and suitable in all respects for the
            Product and for the needs of Shipper. If Shipper fails to conduct
            such an inspection, the Storage Facility will be deemed clean and
            suitable in all respects for the Product and for the needs of
            Shipper.

      1.2   Oiltanking has limited, on-premises facilities for mixing,
            blending and/or circulating Product(s) and if requested to do so
            by Millennium, will perform those operations at no additional
            charge to Millennium and its Shippers. The degree of success, if
            any, from Oiltanking's performance of such operations is dependent
            upon the particular characteristics of the Product(s) involved,
            and the parties agree that the results of such operations are
            beyond the control of Oiltanking. Oiltanking will perform such
            operations only upon receipt of written instructions from
            Millennium or Shipper to do so. OILTANKING HAS DISCLAIMED AND
            MILLENNIUM HEREBY DISCLAIMS ALL RESPONSIBILITY FOR THE RESULTS OF
            SUCH MIXING, BLENDING AND/OR CIRCULATION OF PRODUCT(S) AND NEITHER
            OILTANKING NOR MILLENNIUM MAKES ANY REPRESENTATION, WARRANTY OR
            GUARANTEE OF ANY KIND, INCLUDING WITHOUT LIMITATION WARRANTIES OF
            MERCHANTABILITY OR FITNESS FOR PURPOSE, CONCERNING OR IN ANY WAY
            RELATED TO SUCH MIXING, BLENDING AND/OR CIRCULATION OF PRODUCT(S).
            By requesting that Oiltanking perform mixing, blending and/or
            circulation of Product(s), Shipper acknowledges and agrees that it
            is familiar with the capabilities and limitations of Oiltanking's
            mixing, blending and circulating facilities. Shipper hereby agrees
            that neither Millennium nor Oiltanking shall be liable for any
            damage to Product(s) or any failure, either in part or in whole,
            to attain any specific result from any mixing, blending and/or
            circulation of Product(s) by Oiltanking, and Shipper hereby
            indemnifies and agrees to defend and hold harmless Millennium and
            Oiltanking, their officers and employees, against all claims,
            suits, liabilities and expenses (including,


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            without limitation, reasonable attorneys' fees) concerning or in
            any way related to the mixing, blending and/or circulation of
            Product(s) by Oiltanking except for any claims, suits, liabilities
            and expenses caused by the gross negligence or willful misconduct
            of Oiltanking or Millennium.

      1.3   All inbound and outbound quantities of Product shall be determined
            by meters proven in accordance with the recommendations and
            requirements of the American Petroleum Institute (the "API
            Recommendations"). Millennium will cause Oiltanking to
            periodically prove and, if necessary, recalibrate the inbound
            meter; and Millennium will, or will cause Millennium Pipeline
            Company to, periodically prove and, if necessary recalibrate the
            outbound meter. Shipper shall have the right to have an inspector
            present at offloading of vessels and at all deliveries to the
            Pipeline at Shipper's sole cost. All quantity determinations shall
            be conclusively presumed to be correct after ninety (90) days from
            the date of measurement unless within such 90-day period Shipper
            objects to the quantity determination by notifying Millennium in
            writing.

      1.4   Notwithstanding any other provision of this Agreement and these
            General Terms and Conditions, Millennium is not responsible for
            normal crude degradation-including, without limitation,
            interfacial mixing, tank bottoms, mid tank lines and headers-to
            Shipper's Product transported through or stored in the Storage
            Facility.

Section 2   Cleaning, Removal and Disposal.

      2.1   Shipper agrees to use the equipment and facilities of Oiltanking
            only for the storage of the Product (as defined in Section 3.1 of
            these General Terms and Conditions). Shipper shall be responsible
            for any damages resulting from storage and/or handling of any
            commodity or material which is not expressly authorized under the
            forms hereof. If, due to a change in the characteristics of the
            Product or any other goods or materials of Shipper stored and/or
            handled hereunder, cleaning of the tanks, equipment and/or
            facilities is necessary during the term of this Agreement, Shipper
            agrees to remove and dispose of, or cause to be removed and
            disposed of, any Product goods, material or residue from the
            tanks, equipment and/or facilities and to pay for such cleaning,
            removal and disposal, all of which shall be done at Shipper's
            expense.

      2.2   To the extent Shipper is required under Section 2.1 of these
            General Terms and Conditions to remove and dispose of any Product,
            goods, material or residue, Shipper hereby agrees and warrants to
            Millennium that such removal and disposal will be:

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<PAGE>

            (1)   in strict compliance with all federal, state, and local laws,
                  regulations and ordinances; and

            (2)   registered, logged, charted, or otherwise identified as
                  being the sole and exclusive property of Shipper.

      Notwithstanding any other indemnification contained herein, Shipper
      shall indemnify Millennium for all damages, costs and expenses
      (including, without limitation, reasonable attorneys' fees) resulting
      from Shipper's failure to comply with this Section 2.

Section 3   Product Specifications; Pour Suppressant; Etc.

      3.1   Product Specifications. The "Product" to be delivered to the
            Storage Facility by Shipper and handled by Oiltanking will be
            crude oil or other mutually acceptable, merchantable liquid
            hydrocarbons, subject to the following pour point limitations:

            (1)   during the months of October through March, the maximum
                  Product pour point will be 40 degrees Fahrenheit-after
                  treatment with a pour suppressant additive if necessary; and

            (2)   during the months of April through September, the maximum
                  Product pour point will be 60 degrees Fahrenheit-after
                  treatment with a pour suppressant additive if necessary.

      3.2   Product Safety Data. Shipper shall provide Oiltanking's Traffic
            Department with proper material safety data sheets and lab
            analysis of Benzene content, RVP/True Vapor Pressure and H2S to
            determine handling, storage and loading requirements. Shipper
            warrants to Millennium that all materials will comply with
            Oiltanking's permit-specifically.

            (1)   Benzene cannot exceed ten percent (10.0%) by weight;

            (2)   True Vapor Pressure during storage cannot exceed 11 PSIA,
                  provided that components with higher vapor pressure can be
                  discharged as long as they are blended down into low vapor
                  pressure Product residing in tankage at the time of
                  discharge; and

            (3)   H2S cannot exceed 10 ppm vapor.

      3.3   Cost. All costs associated with the adding of Pour Suppressant and
            the Pour Suppressant material shall be for Shipper's account.


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<PAGE>

      3.4   Right to Reject Product. The viscosity, pour point and any pour
            point suppressant being used must be reported to Millennium and
            Oiltanking prior to the arrival of the vessel. Millennium has the
            right to reject-or to direct Oiltanking to reject-any cargo if, in
            the sole opinion of Millennium, Oiltanking's pumps will not be
            able to adequately pump the cargo to the Storage Facility or the
            Pipeline System.

Section 4   Title and Custody. Title to the Product stored and/or handled
            hereunder shall always remain with Shipper or the party for whom
            Shipper has custody of the Product. Oiltanking shall be deemed to
            have custody of the Product from the time it enters (the In-Bound
            Meter until it exits the Out-Bound Meter.

Section 5   Insurance. The rates and prices quoted herein do not include any
            insurance on the Product. Insurance on Product(s) to be stored at
            the Storage Facility, if any is desired by Shipper, will be
            carried by Shipper at its sole cost and expense. If Shipper
            carries any insurance on the Product, Shipper will waive, and will
            cause its insurance carrier(s) to waive, any rights of subrogation
            against Millennium. Shopper will deliver copies of such waivers to
            Millennium on request.

Section 6   Liability and Damages.

      6.1   Shipper shall, at no cost to Millennium, defend, exonerate,
            indemnify and save harmless Millennium from and against:

            (1)   any and all liability for loss of, and any and all damage
                  to, the Product or property of Shipper, Millennium,
                  Oiltanking or others, and any and all liability for injury
                  (including death) to persons (including employees of
                  Millennium, Oiltanking and Shipper), and any and all claims
                  or actions in connection with such loss or damage, based
                  upon, arising out of or occurring in connection with the
                  deposit, storage, withdrawal or subsequent transportation or
                  disposal of Shipper's Product, except such claims as
                  directly arise out of Millennium's willful misconduct or
                  gross negligence in the safekeeping and handling of
                  Shipper's Product or property; and

            (2)   any and all fines, penalties or liabilities to any
                  governmental authority or a third person specifically caused
                  or resulting from any act or omission of Shipper or from
                  Shipper's breach of this Agreement.

            Millennium shall defend and indemnify Shipper for any loss or
            damage caused by Millennium's gross negligence or willful
            misconduct. The burden of proving Millennium's willful misconduct
            or gross negligence in the safekeeping and handling of Shipper's
            Product or property shall be upon Shipper, however.


                                          4
<PAGE>


      6.2   NOTWITHSTANDING ANY OTHER PROVISION OF THIS AGREEMENT, IT IS
            UNDERSTOOD AND AGREED THAT, IN THE EVENT OF ANY WILLFUL OR
            NEGLIGENT LOSS OF OR DAMAGE TO SHIPPER'S PRODUCT, MILLENNIUM SHALL
            NOT IN ANY EVENT BE LIABLE TO SHIPPER FOR MORE THAN EITHER (i) A
            SIMILAR QUANTITY OF LIKE-KIND PRODUCT (AS WAS LOST OR DAMAGED) TO
            BE PROVIDED BY MILLENNIUM TO SHIPPER OR (ii) THE FAIR MARKET VALUE
            OF THE PRODUCT LOST OR DAMAGED MEASURED AS OF THE DATE OF LOSS, NOR
            SHALL MILLENNIUM EVER BE LIABLE FOR PUNITIVE, INCIDENTAL, SPECIAL OR
            CONSEQUENTIAL DAMAGES OR LOST PROFITS, REGARDLESS OF HOW OR BY
            WHOM SUCH LOSS OR DAMAGE SHALL HAVE OCCURRED OR BEEN CAUSED. Fair
            market value of the Product lost or damaged shall be conclusively
            determined by Platt's Spot Assessments for the Texas Gulf Coast.
            Millennium will receive a credit for the salvage value of any
            damaged Product.

      6.3   Shipper agrees to execute in its name, pay for and furnish to
            Millennium and Oiltanking all information, documents, labels,
            placards, containers and other materials which may be required by
            statutes, ordinances, rules or regulations of the U.S. Coast
            Guard, OSHA, Departments of Transportation or Energy or any other
            governmental body or agency having jurisdiction, relating to the
            describing, packaging, receiving, storing, handling, disposal or
            shipping of the Product (the foregoing being hereinafter
            collectively referred to as the "Regulations") at or from the
            Storage Facility, together with detailed written instructions as
            to their use and disposition. Shipper further agrees to indemnify
            and hold harmless Millennium and its agents, employees, officers
            and directors from and against any fines, loss, damage or expense
            (including without limitation reasonable attorneys' fees)
            resulting from the violation of the Regulations or from any
            proceedings in which such a violation of the Regulations is
            charged, except when directly arising from Millennium's failure to
            reasonably follow the written instructions of Shipper.

      6.4   EXCEPT AS EXPRESSLY HEREIN PROVIDED, THERE ARE NO GUARANTEES,
            WARRANTIES OR REPRESENTATIONS BY MILLENNIUM OF ANY KIND, EXPRESS
            OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTIES OF
            MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, WHETHER
            ARISING BY OPERATION OF LAW OR OTHERWISE.


                                      5
<PAGE>

Section 7   Taxes, Assessments and Other Governmental Charges.

      7.1   In addition to any other charges to be paid by Shipper hereunder,
            Shipper shall pay for and shall hold Millennium harmless from any
            and all taxes, duties, import fees, assessments or other charges
            (collectively, "Taxes") levied by any governmental body upon
            Shipper's Products stored at the Storage Facility, as well as for
            any additional or increased Taxes levied upon or charged to
            Millennium by reason of Shipper's storage of Product at the
            Storage Facility; provided, however, that, if the Storage Facility
            is used by more than one shipper, Shipper will have no obligation
            to pay more than its proportionate share of such Taxes or
            increased or additional Taxes. Such Taxes or increased or
            additional Taxes shall be paid by Shipper upon receipt of written
            notice thereof from Millennium. In the event Shipper does not
            timely make any required payments for Taxes and Millennium is
            required to make such payments, Shipper will reimburse Millennium
            for all Taxes paid, plus interest for the period beginning on the
            date Millennium pays such Taxes and continuing until paid by
            Shipper. Interest on any of Shipper's Taxes paid by Millennium
            pursuant to this Section 7.1 will accrue at a rate equal to the
            lesser of (i) two percent (2.0%) plus the "Prime Rate" published in
            the Wall Street Journal on the date Millennium pays such Taxes and
            (ii) the maximum contract rate permitted by the applicable usury
            laws of the State of Texas. Shipper is hereby advised that
            Oiltanking is required by law to report Shippers Product inventory
            to local taxing authorities.

      7.2   If Oiltanking imposes any additional charge, fee or cost on
            Millennium due to (a) the imposition of a new tax, fee or levy
            upon Oiltanking by any governmental body or agency because of
            Oiltanking's proximity to the Ship Channel or because of
            Oiltanking's operation of the Storage Facility or (b) a
            requirement imposed by any new governmental regulation that
            Oiltanking install additional equipment or to modify its
            facilities or standard handling procedures in order to continue to
            provide the services contemplated by this Agreement, then
            Millennium may request that Shipper pay its reasonable and
            proportionate share of such additional charge, fee or cost. In the
            event Shipper elects not to pay any such charge, fee or cost,
            Millennium may terminate this Agreement upon thirty (30) days
            written notice to Shipper without any liability.


                                      6
<PAGE>

Section 8   Loading and Unloading of Vessels and Barges.

      8.1   Millennium will use its best efforts to cause Oiltanking to load
            and unload vessels and barges at its dock in order of their
            arrival. Millennium will not be responsible, however, for
            demurrage or for delays to vessels or barges due to the
            unavailability of the dock or for any other reason. Vessels and
            barges delivering Shipper's Product to the Storage Facility must
            supply all necessary manpower and machinery to pump to shore
            tanks. Immediately upon completion of loading and/or unloading of
            vessels or barges, Shipper will cause such vessel or barge to
            vacate Oiltanking's dock. If (a) a vessel or barge transporting
            Shipper's Product refuses to vacate the dock and (b) Oiltanking
            has provided written notice of the vessel's refusal to (i)
            Shipper, (ii) Millennium and (iii) the owner, agent, master or
            mate of the vessel or barge, then Millennium may assess Shipper a
            fee in an amount not greater than $1,500.00 per hour ($500.00 per
            hour for barges) or any portion of an hour that the vessel or
            barge remains docked after the parties listed above have been
            notified.

      8.2   Shipper will pay all inspection fees and all fees and charges
            attributable to the vessel or barge (including, without
            limitation, pilots, tugs, line handlers, towing, light and
            port dues, licensed tankermen and/or agents).

      8.3   All vessels and barges utilizing the Storage Facility shall be
            solely responsible or providing, maintaining and tending their
            mooring lines, and Shipper shall indemnify and save Millennium
            harmless from all liability, cost or damages resulting from
            Shipper's vessel's or barge's failure to comply with this
            provision.

      8.4   Notwithstanding anything to the contrary contained in this
            Agreement, it is mutually understood and agreed by Shipper and
            Millennium that Shipper will employ tankships which are (utilizing
            the ship's pumps and the ship's power) capable of discharging
            their cargo at an average rate of not less than 20,000 bbls/hour,
            or maintaining 100 psig at ship's rail, provided shore facilities
            are capable of receiving same. If any vessel discharging Shipper's
            Product does not maintain this average pump rate for twelve (12)
            consecutive hours, Oiltanking can interrupt the discharge and
            require the vessel to leave if it has another need for the berth.
            If this happens, the vessel will be placed at the end of rotation
            of the vessels scheduled into Oiltanking's dock.

      8.5   Oiltanking or Millennium may refuse to accept any barges or
            vessels which are not properly equipped with U.S. Coast Guard
            approved vapor collection and return equipment compatible with the
            existing Oiltanking system.


                                      7
<PAGE>

Section 9   Substitution of Equipment and Facilities. In the event that
            Oiltanking desires for its own convenience to transfer Shipper's
            Product to other tanks, equipment and/or facilities, Oiltanking
            may do so provided that the transfer of Product is at the risk and
            expense of Oiltanking and that the substituted tanks, equipment
            and/or facilities are at least equal in quality and size to the
            tanks, equipment and facilities set forth elsewhere in this
            Agreement.

Section 10  Delivery and Redelivery.

      10.1  Shipper shall make good faith, reasonable efforts to schedule the
            arrival of its vessels ratably.

      10.2  Shipper shall give Millennium and Oiltanking advance written
            notice of the receipt and/or delivery of each shipment of Product,
            which notice shall specify:

            (1)   the name of the carrier;

            (2)   the carrying vessel or pipeline;

            (3)   the custody transfer point;

            (4)   the type, grade and quantity of Product;

            (5)   the estimated time of arrival thereof; and

            (6)   any other pertinent information, including without
                  limitation any and all documentation required by law
                  concerning the receipt, delivery, handling or storage of
                  Products.

      10.3  Shipper will deliver such notice to Millennium and Oiltanking not
            less than seventy-two (72) hours in advance as to tank barges, four
            (4) days in advance as to other vessels, and five (5) days in
            advance as to pipelines. It is Shipper's sole responsibility to
            arrange, coordinate and expedite all carrier movements. Oiltanking
            will cooperate in arranging, coordinating and expediting such
            movements, but any such cooperation will not constitute a waiver of
            this clause.

      10.4  Under ordinary circumstances, Millennium will cause Oiltanking to
            receive shipments of Product from tank barges, other vessels or
            pipelines in the order in which they arrive at the Storage
            Facility, but Oiltanking will nevertheless be entitled to depart
            from such order for the purpose of complying with the regulations
            or directives of applicable government authorities or for insuring
            the smooth working of the Storage Facility operations. From time
            to time, Oiltanking may, in its sole discretion, direct Shipper's
            vessels to dock


                                      8
<PAGE>

            and offload at the dock of TE Products Pipeline Company ("TEPPCO")
            across the Nueces River from the Oiltanking dock.

      10.5  Although every effort will be made to remove as much material as
            possible from storage tanks at the Storage Facility, Millennium
            has no obligation to, nor to cause or require Oiltanking to,
            squeegee out any of the foregoing. Millennium will, however, cause
            Oiltanking to remove as much material as practicable using
            Oiltanking's standard equipment and procedures. Millennium and
            Shipper agree that only liquid material will be pumped through
            Oiltanking's system.

      10.6  Oiltanking will not perform any services aboard any vessel or
            barge. Millennium will, however, cause Oiltanking to provide labor
            necessary to perform the services agreed upon herein in accordance
            with Oiltanking's established Storage Facility practices. Any
            additional costs that may arise -- whether such costs are related
            to labor or otherwise -- in connection with the control and
            movement of material or the handling of equipment or hoses between
            Oiltanking's permanent pipeline connection and any tank barge or
            other vessel shall be solely for Shipper's account, and Millennium
            will not be liable for all or any portion of any such costs.

Section 11  Product Lien. Shipper hereby grants to Millennium an express
            contractual lien and security interest upon all Products at any time
            stored or handled hereunder for all of the charges and amounts
            payable by Shipper to Millennium hereunder. Said contractual lien
            and security interest may be foreclosed by Millennium in accordance
            with the provisions of Article 9 of the Texas Uniform Commercial
            Code in effect from time to time. Such liens shall not be exclusive
            but shall be cumulative and in addition to all other legal and
            equitable liens, rights and remedies of Millennium. Notwithstanding
            anything to the contrary contained herein, the lien granted in this
            Section 11 is only applicable to indebtedness owed to Millennium by
            Shipper under this Agreement.

Section 12  Adjustments.

      12.1  If any new or amended Legal Requirement becomes effective at any
            time during the Term of this Agreement and requires Millennium to
            undertake new or additional efforts to become or remain in
            compliance with all then effective Legal Requirements, Millennium
            may, at its option, pass through to the Shipper all or any portion
            of the cost of those additional compliance efforts on a pro rata
            basis.

      12.2  Throughout the Term of this Agreement, Millennium may adjust the
            rates set forth in Section 3 of this Agreement. The adjustment, if
            any, made during any Contract Year will not exceed an amount (the
            "PPI Rate Adjustment")


                                      9
<PAGE>

            equal to the difference (on a percentage basis) between (i) the
            Producer Price Index for Industrial Commodities as compiled by the
            United States Bureau of Labor Statistics (the "PPI") for the
            immediately preceding calendar year (the "Prior Calendar Year")
            and (ii) the PPI for the calendar year immediately preceding the
            Prior Calendar Year. Notwithstanding any other provision of this
            Section 12.2, however, if Millennium does not impose a PPI Rate
            Adjustment during a given Contract Year, Millennium reserves the
            right to impose a PPI Rate Adjustment during any subsequent
            Contract Year in an amount not to exceed the aggregate PPI Rate
            Adjustments not previously imposed on Shipper by Millennium.

Section 13  Eminent Domain. If use of Oiltanking's equipment and facilities
            for storage and/or handling of the Product is restrained or
            enjoined by judicial process or terminated by any governmental
            authority or terminated by right of eminent domain, Millennium
            may, at its option and without liability to Shipper, terminate
            this Agreement upon thirty (30) days written notice to Shipper.

Section 14  Collection of Excise Taxes.

      14.1  Shipper shall be solely responsible for collecting and disbursing
            any and all federal, state and/or local excise taxes now or
            hereafter enacted and payable in respect to any and all Product
            delivered hereunder, and Shipper shall be solely responsible for
            reporting and/or filing any tax returns in connection with same.
            Shipper shall indemnify and hold Millennium harmless from any and
            all expenses and liability (including without limitation fines,
            penalties and reasonable attorneys' fees) in respect to the
            collection, disbursement and reporting of all such taxes.

      14.2  Millennium will not be obligated to release Shipper's Product
            unless and until Shipper has provided both Millennium and
            Oiltanking with its IRS Excise Tax Registration Number and/or a
            Certificate of Registry.

      14.3  Prior to transferring any Product, Millennium may require Shipper
            to supply both Millennium and Oiltanking with a signed certificate
            from the proposed transferee setting forth the following:

            (1)   the name and address of the transferee;

            (2)   a declaration that the transferee is registered with the IRS;

            (3)   the identity of the IRS District Director with whom the
                  transferee is registered; and

            (4)   transferee's IRS Excise Tax Registration Number.


                                      10
<PAGE>

      14.4  In connection with the handling of Shipper's Product, in the event
            that Millennium ever becomes liable for the federal excise tax,
            Millennium will have the right to retain custody of Shipper's
            Product until such time that Shipper has provided to Millennium an
            irrevocable letter of credit (with a bank reasonably satisfactory
            to Millennium) or other sufficient collateral reasonably
            calculated to indemnify Millennium for any federal excise taxes,
            fines and penalties that Millennium may be or become required to
            pay in connection with Shipper's Product.

Section 15  Pollution. In the event of a discharge or threat of discharge of
            Product or other pollutant or hazardous substance from Shipper's
            vessel or the Storage Facility upon the waters adjacent to the
            Storage Facility while Shipper's vessel is at or near the Storage
            Facility, Shipper shall-and Millennium will cause Oiltanking to-
            cooperate and promptly take such steps as are necessary to prevent
            further discharge or threat, and to minimize damage resulting from
            and to clean up any such discharge, regardless of fault. The cost
            of such steps shall be recoverable between Oiltanking and Shipper
            according to their comparative fault. Failing such an agreement
            within ninety (90) days of the date of discharge, the matter shall
            be subject to binding arbitration in accordance with the rules of
            the American Arbitration Association. Notwithstanding anything in
            this paragraph to the contrary, the provisions of this paragraph
            shall not affect, as between the parties, any liability of either
            party to third parties for costs or damages other than clean up
            costs expended by the parties pursuant to this Section 15, whether
            such be private or governmental parties.

            [The remainder of page was intentionally left blank]


                                      11
<PAGE>

                            INCENTIVE RATE CONTRACT

      This Agreement is entered into as of the ___ day of January 2000, by
and between Millennium Pipeline Company, L.P., a Texas limited partnership
and Clark Refining and Marketing, Inc., a Delaware corporation.

      WHEREAS, Millennium is the owner of a crude oil pipeline system
extending from a point near Beaumont, Texas to a point near Longview, Texas
known as the Millennium Pipeline System; and

      WHEREAS, Clark desires to ship crude oil on the Millennium Pipeline
System;

      NOW THEREFORE, in consideration of the premises and the mutual covenants
contained herein the Parties agree as follows:

      1. DEFINITIONS.  When the following terms are used in this Agreement, they
shall have the meaning assigned below:

      1.1   "Affected Party" shall have the meaning ascribed to it in Article
            11.

      1.2   "Agreement" shall mean this incentive Rate Contract.

      1.3   "Barrel" shall mean forty-two (42) U.S. gallons of 231 cubic
            inches per gallon corrected for temperature to 60(degrees)
            Fahrenheit in accordance with A.S.T.M.D-1250 Petroleum Measurement
            Table 6B (unabridged) or latest revision thereof.

      1.4   "Clark" shall mean Clark Refining and Marketing, Inc.

      1.5   "Commencement Date" shall mean the first month following the month
            in which the later of the following events occurs: (i) Millennium
            Terminal Company executes a definitive agreement with Oiltanking
            in connection with the Storage


                                      1
<PAGE>

            Facility; and (ii) all capital projects necessary to render the
            Pipeline operational are complete to the degree required to place
            the Pipeline into service.

      1.6   "Contract Year" shall mean a period of twelve (12) consecutive
            months beginning on the Commencement Date and each period of
            twelve (12) consecutive months thereafter.

      1.7   "Deficiency Payment" shall mean the amount of money owed by Clark
            to Millennium for volumes not shipped as required by Section 4.5.

      1.8   "Deficiency Volumes" shall mean the number of barrels not shipped
            by Clark as required by Section 4. 1.

      1.9   "Force Majeure" shall have the meaning ascribed to it in Article
            11.

      1.10  "Initial Term" shall have the meaning ascribed to it in Section 2.1.

      1.11  "Maximum Viscosity Surcharge" shall have the meaning ascribed in
            Section 3.2.

      1.12  "Millennium" shall mean Millennium Pipeline Company, L.P.

      1.13  "Party" or "Parties" shall mean Millennium and Clark individually
            or jointly, as the case may be.

      1.14  "Pipeline" shall mean the pipeline owned by Millennium.

      1.15  "PPI" shall mean the Producer Price Index for Industrial
            Commodities as published by the United States Bureau of Labor
            Statistics.

      1.16  "PPI Rate Adjustment" shall have the meaning ascribed to it in
            Section 33.

      1.17  "Prior Calendar Year" shall have the meaning ascribed to it in
            Section 3.3.

      1.18  "SSU" shall mean saybolt seconds universal.


                                      2
<PAGE>

      1.19  "Term of this Agreement" shall mean a combination of the Initial
            Term and all Renewal Terms.

      1.20  "Transportation Credits" shall have the meaning ascribed to them
            in Section 4.3.

      2.    TERM

      2.1 Initial Term.  The Initial Term of this Agreement shall be for 5
Contract Years beginning on the Commencement Date and continuing through the
end of the fifth Contract Year. Millennium will endeavor to provide Clark with
as much written notice of the Commencement Date as possible; however, the
obligations of Clark and Millennium will commence on the Commencement date
without the regard to the length of such notice. Millennium anticipates that
the Commencement Date will occur on or about April 1. 2000; this Agreement
will terminate, however, and the parties respective obligations will thereafter
be excused-if the Commencement Date does not occur on or before October 1,
2000.

      2.2 Renewal.  This Agreement will be automatically renewed and extended,
without the taking of any additional action by any party, for consecutive one
(1) year periods.

      2.3 Termination. Either Party may terminate this Agreement, effective as
of the end of the Initial Term or any Renewal Term, by delivering to the other
Party written notice at least six (6) months prior to the effective date
of the termination.

      3.    RATES

      3.1 Contract Rate. For movements of the first 18,250,000 barrels in any
Contract Year, Clark shall pay to Millennium forty-three cents ($0.43) per
barrel. For movements over the first 18,250,000 barrels in any Contract Year,
Clark will pay forty and eighty-five one-hundredths cents ($0.4085) per
barrel.


                                      3
<PAGE>

      3.2 Viscosity Surcharge. In addition to the rates set out in Section
3.1, all crude having a viscosity greater than forty (40) SSU at 100(degrees)F
shall be subject to an additional charge of fifty-two hundredths of a cent
($0.0052) per each unit change in viscosity above 40 SSU (rounded to the nearest
one hundredth of a cent). No crude will be accepted for transportation if its
viscosity exceeds one hundred (100) SSU at 100(degrees)F.

      3.3 Rate Adjustment. At the end of each Contract Year throughout the
Term of this Agreement, Millennium may adjust the tariff rate set forth in
Section 3.1 above. The adjustment, if any, made during any Contract Year will
not exceed an amount (the "PPI Rate Adjustment") equal to the difference (on a
percentage basis) between (i) the Producer Price Index for Industrial
Commodities as compiled by the United States Bureau of Labor Statistics (the
"PPI") for the immediately preceding calendar year (the "Prior Calendar Year")
and (ii) the PPI for the calendar year immediately preceding the Prior Calendar
Year. Notwithstanding my other provision of this Section 3.3, however, if
Millennium does not impose a PPI Rate Adjustment during a given Contract Year,
Millennium reserves the right to impose a PPI Rate Adjustment during any
subsequent Contract Year in an amount not to exceed the aggregate PPI Rate
Adjustments not previously imposed on Clark by Millennium.

      3.4 Additional Charges. If Millennium's costs go up due to any (a) new
tax, fee or levy is made by any governmental body or agency or (b) requirement
imposed by any new governmental regulation requiring Millennium to install
equipment or to modify its facilities in order to continue to provide the
services contemplated by this Agreement, then Millennium may request Clark to
pay its reasonable and proportionate share of such additional charge, fee or
cost. In the event that Clark elects not to pay any such charge, fee or cost,
Millennium may terminate this


                                      4
<PAGE>

Agreement upon thirty (30) days written notice to Clark, and neither party
would have any further liability other than to make payments then due and
payable.


      4.    VOLUME COMMITMENTS; DEFICIENCY

      4.1 Volume Commitment. Throughout the Term of this Agreement, Clark
shall tender to Millennium 18,250,000 barrels of Crude oil for movement
through the Pipeline during each Contract Year. If Clark's shipments
throughout the Pipeline do not reach 18,250,000 barrels for any Contact Year,
Clark shall pay to Millennium forty-three (43) cents per barrel for each
barrel below such commitment. The barrels shipped by Clark under this
commitment are to be shipped ratably at a monthly average of 50,000 barrels
per day.

      4.2 Volumes Not Shipped. In calculating Clark's average tenders under
Section 4.1, any days on which a force majeure is declared by Clark pursuant
to Section 11 shall be excluded. In addition, any volumes which Millennium
does not accept for any reason, including, without limitation, a force majeure
declared pursuant to Section 11, shall be included in Clark's volumes shipped
for the purpose of calculating the average barrels per day of Clark's shipments.

      4.3 Transportation Credits. Any Deficiency Payment made by Clark to
Millennium pursuant to Section 4.1 shall be deemed to be a prepayment for
transportation and will be applied accordingly as a credit against any tariff
rates applicable to any volumes transported by Millennium for Clark in excess
of the commitment of 18,250,000 barrels for a Contract Year referenced in
Section 4.1 of this Agreement. Such Transportation Credits shall expire upon the
termination of this Agreement.

      4.4 Deficiency Calculation. At the end of each Contract Year, Millennium
shall calculate, after applying the allowable credits and exclusions
referenced in Sections 4.2, the


                                      5
<PAGE>

Deficiency Volumes. Millennium shall render an invoice to Clark within thirty
(30) days of the end of any Contract Year which shows the computation of the
Deficiency Volumes and the amount of Deficiency Payment due.

      4.5 Deficiency Payment. Clark shall pay the amount of the Deficiency
Payment due within thirty (30) days of the receipt of the invoice referred to
in Section 4.4.

   5. BILLINGS AND PAYMENTS

      5.1 Billings. Billings for movements shall be governed by the applicable
tariffs. Billings for Deficiency Payments shall be governed by Section 4.4.

      5.2 Payments. Likewise, payments shall be governed by the applicable
tariff or Section 4.5, as the case may be.

      5.3 Late Payments. If payment is not made as required by the tariff, the
tariff provisions shall apply. If payment is not made as required by Section
4.5, the unpaid balance shall bear interest from the date due at a rate equal
to the lesser of (i) two percent (2.0%) plus the "Prime Rate" published in the
Wall Street Journal on the date such amount is due, and (ii) the maximum
contract rate permitted by the applicable usury laws of the State of Texas,
plus attorneys' fees, court costs and other costs in connection with the
collection of unpaid amounts.

      6. COMPLIANCE WITH LAW. Clark acknowledges that Millennium is a common
carrier pipeline subject to regulation by agencies and commissions having
jurisdiction over Millennium. This Agreement is subject to all valid laws,
ordinances, regulations, rules and orders of government authorities applicable
to the operation of common carrier crude oil pipelines and to all of the
provisions of Millennium's filed tariffs.


                                      6
<PAGE>

      7. CHOICE OF LAW. THIS AGREEMENT, AND THE LEGAL RELATIONS BETWEEN THE
PARTIES WITH RESPECT TO THIS AGREEMENT, SHALL BE GOVERNED AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS WITHOUT REGARD TO RULES
CONCERNING CONFLICTS OF LAWS.

      8. ASSIGNMENT. Either party to this Agreement may assign all or any
portion of its interest in this Agreement to any financially and operationally
capable third-party; no such assignment, however, will relieve the assignor
from any portion of its obligations under this Agreement. Nothing in this
Section 8 will be construed as prohibiting any party from pledging or
mortgaging its rights under this Agreement to secure any indebtedness.

      9. NOTICES. Any notice required to be given under any provision of
this Agreement must be in writing and directed to:

                  To Millennium:   Millennium Pipeline Company, L.P.
                                   c/o Equilon Pipeline Company LLC
                                   Two Shell Plaza
                                   P.O. Box 2648
                                   Houston, TX 77252-2648
                                   Attn: General Manager, Joint Ventures
                                   Telephone: (713) 241-3154
                                   Fax: (713) 241-1124

                                    With a copy to:

                                    Millennium Pipeline Company, L.P.
                                    c/o Black Hills Millennium Pipeline, Inc.
                                    4669 Southwest Freeway, Suite 400
                                    Houston, TX 77027
                                    Attn., Scott E. Borinaster, Executive
                                           Vice President
                                    Telephone: (713) 942-0595
                                    Fax: (713) 942-7915


                                      7
<PAGE>

                   To Clark:        Clark Refining & Marketing, Inc.
                                    8182 Maryland Avenue
                                    6th Floor
                                    Clayton, Missouri 63105 .
                                    Attn: John Overbey, Vice President
                                    Telephone: 314-854-1405
                                    Fax: 314-854-9635

                                    With a copy to:

                                    Clark Refining & Marketing, Inc.
                                    8192 Maryland Avenue
                                    Clayton, Missouri 63105
                                    Attn: Legal Department
                                    Telephone: (314) 854-9666
                                    Fax: (314) 854-1455

All notices will be deemed received by the addressee upon the earlier of (i)
the actual receipt by the person or persons to whom the notice is directed
(including the receipt of a fax confirmation by the sender of the notice) and
(ii) 3 days following the deposit of a properly addressed notice in the United
States mail, postage prepaid.

      10. COUNTERPARTS.  The Parties may execute this Agreement in two or more
counterparts, which shall, in the aggregate, constitute a single agreement.

      11. FORCE MAJEURE. If, by reason of Force Majeure, either Party is
rendered unable, wholly or in part, to carry out its obligations under this
Agreement, other than its obligation to pay any amount of money due and owing
under the terms of this Agreement and, if the Party so prevented from the
performing (the "Affected Party") gives notice and reasonably full particulars
of such Force Majeure in writing to the other Party within 24 hours after the
occurrence of the event relied on, the Affected Party will be excused, to the
extent its performance is affected by the Force Majeure, during the
continuation of the event relied on; provided, however, that the Affected
Party


                                      8
<PAGE>

shall use its best efforts to cure the Force Majeure event as soon as
possible; but provided further that settlement of labor disputes will be
strictly within the discretion of the Affected Party. As used in this Section
11, "Force Majeure" includes, without limitation, acts of God; acts of a
public enemy; fires; compliance with any court order, law, regulation or
ordinance of any governmental authority having jurisdiction over the Affected
Party; civil disturbances; shutdowns for purposes of necessary repair,
relocation or construction of the Pipeline; breakage or accidental damage to
any pipe, machinery or equipment comprising the Pipeline or the cargo ship
transporting Clark's Product to the Storage Facility or the Storage Facility;
the necessity for testing (as required by any governmental authority or as
deemed necessary by Millennium) for the safe operation of the Pipeline; the
necessity of making repairs or alterations to any pipe, machinery or equipment
comprising the Pipeline or the Storage Facility; inability of either Party to
obtain necessary material, supplies or permits, or labor to perform or comply
with any obligation or condition of this Agreement; inability to obtain or
retain rights-of-way; and any other cause, whether of a kind recited herein or
not, that is not reasonably within the control of the Affected Party.

      12. GOVERNMENTAL REGULATION. This Agreement is subject to all present
and future valid laws, rules, regulations and lawful orders (collectively, the
"Legal Requirements") of all governmental authorities now or hereafter having
jurisdiction over the Pipeline. If any Legal Requirement is imposed or if any
existing Legal Requirement is amended that renders Millennium or Clark unable
to lawfully fulfill its obligations under this Agreement (other than to pay
sums of money due and owing at the time such legal Requirement is imposed or
amended), then this Agreement will be deemed reformed to conform to the then
existing Legal Requirements.


                                      9
<PAGE>

      13. CAPTIONS. The captions identifying the sections and subsections of
this Agreement are for convenience only and are not intended by the Parties to
affect the meaning or interpretation of the provisions of this Agreement.

      14. ENTIRE AGREEMENT. This Agreement constitutes the entire agreement
between the Parties with respect to the matters addressed herein, and this
Agreement supersedes any prior understanding or other written or oral
agreements related to these matters.

      15. SEVERABILITY. If any provision of this Agreement is determined to be
invalid or unenforceable to any extent, the remaining provisions of this
Agreement will remain in effect and will be enforced to the maximum extent
permitted by law.

      16. AMENDMENT. This Agreement may be amended only by a written agreement
executed by Millennium and Clark.



                   [SIGNATURES BEGIN ON THE FOLLOWING PAGE]


                                      10
<PAGE>

      IN WITNESS WHEREOF, the Parties have executed this Agreement through
their authorized representatives as of the date first above written.

                                    MILLENNIUM PIPELINE COMPANY, L.P.,

                                    By:   Equilon Pipeline Company LLC,
                                          a General Partner

                                           By: /s/ Bernie Lednicky
                                               ________________________________
                                           Printed Name: Bernie Lednicky
                                           Title: Director, Joint Ventures



                                    By:   Black Hills Millennium Pipeline, Inc.
                                          a General Partner

                                           By: /s/ Scott E. Bormaster
                                               ________________________________
                                           Printed Name: Scott E. Bormaster
                                           Title: Executive Vice President



                                    CLARK REFINING & MARKETING INC.

                                     By: /s/ John Overbey
                                         ________________________________
                                     Printed Name: John Overbey
                                     Title: Vice President, Crude Oil Supply





                THIS IS THE SIGNATURE PAGE TO THE INCENTIVE RATE CONTRACT