Document:

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                                                                Exhibit 10.29

                                 AMENDMENT NO. 2
                                       TO
                            PRODUCT SUPPLY AGREEMENT

     This Amendment No. 2 is effective 1 June, 2001, by and between The Premcor
Refining Group, Inc., formally known as Clark Refining & Marketing, Inc., a
corporation organized and existing under the laws of the State of Delaware
(hereinafter referred to as "Buyer") and Air Products and Chemicals, Inc., a
corporation organized and existing under the laws of the State of Delaware
(hereinafter referred to as "Seller").

                               WITNESSETH THAT:

WHEREAS, Seller and Buyer are parties to a Product Supply Agreement dated as
of 1 August 1999 (hereinafter referred to as the "Agreement"); and

WHEREAS, the parties now wish to further amend the Agreement as set forth
herein.

NOW, THEREFORE, in consideration of the foregoing and the terms and conditions
set forth herein, Seller and Buyer agree to amend the Agreement as follows:

1.   Add new Section 12.3, as follows:

"12.3 Indemnification. Nothing herein shall be construed to require Seller to
take any action to attempt to secure a reduction in Buyer's Pro Rata Share of
property taxes, ad valorem taxes and payments under the Property Tax
Agreements (hereinafter referred to as an "Action") if, in the judgment of
Seller's Vice President, Taxes or his designee, such Action could have a
potential adverse impact upon Seller, including an increase in assessed value
and/or an increase in the Seller's portion of property taxes, ad valorem taxes
and payments under the Property Tax Agreements. Notwithstanding the forgoing,
in the event that Buyer should reasonably request that Seller take such
Action, and Seller agrees to comply, then the following provisions shall
apply:

     (A) It is agreed that Seller shall be entitled for reimbursement for any
costs and expenses that it may incur with respect to an Action. In the event
that Seller, in its absolute discretion, shall seek such reimbursement, then
Buyer shall reimburse Seller for (i) all costs and expenses of any type and
nature incurred by Seller as a result of or relating to taking of such Action
and (ii) the actual costs (including wages, benefits, overhead, etc.) of time
spent by Seller's employees dealing with the Action.

     (B) Without limitation to the forgoing, Buyer shall pay for, defend, with
counsel satisfactory to Seller, protect, indemnify and save harmless Seller
from and against any and all liabilities, obligations, claims, investigations,
inquiries, judgments, damages, penalties, causes of action, costs and expenses
(including, without limitation, attorneys' fees and expenses) imposed upon or
incurred by or asserted against Seller by reason of (i) taking an Action, (ii)
any misrepresentation by Buyer hereunder, or (iii) any failure on the part of
the Buyer to perform or

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observe any of its agreements or obligations under this Agreement. For purposes
of this Section 12.3, any increase in property taxes, ad valorem taxes or
payments under the Property Tax Agreements over and above that which Seller
would have been required to have paid but for Buyer's request that Seller take
an Action shall be considered to be an indemnificable expense hereunder.

     (C) Without limitation to the foregoing, Buyer shall pay within fifteen
business days of Seller's written request for payment all judgments, damages,
penalties, fines, assessments and other charges asserted against and incurred
by Seller with respect to any of the matters included in Buyer's indemnity
obligation hereunder.

     (D) In the event that any payment which Buyer is obliged to make to
Seller under this Agreement is not made within the fifteen day period set
forth in subsection (C), above, such payment shall bear interest at the rate
of eight percent per annum from the expiration date of such fifteen day period
until the date payment is actually received by Seller."

2.   All defined terms set forth herein without definition shall have the
meaning given such term in the Agreement.

3.   Except as set forth herein, all other terms and conditions of the
Agreement shall remain unchanged and continue in full force and effect.

                                  AIR PRODUCTS AND CHEMICALS, INC.

                                  By:    /s/  Dorothy Green
                                         -------------------------------------
                                  Title:   Assistant Treasury-Tax
                                         -------------------------------------

                                  THE PREMCOR REFINING GROUP, INC.

                                  By:    /s/  Dennis B. Eichholz
                                         -------------------------------------
                                  Title:   Controller
                                         -------------------------------------

                                      2<PAGE>
                                                                Exhibit 10.30

                         CRUDE OIL PURCHASE AGREEMENT

This Agreement is made on the 8th day of March, 1999.

BETWEEN:         KOCH PETROLEUM GROUP, L.P.
                 (hereinafter referred to as "Koch")

AND:             CLARK REFINING & MARKETING, INC.
                 (hereinafter referred to as "Clark")

In consideration of the premises and of the mutual covenants, conditions and
agreements hereinafter set forth, the parties agree as follows:

1.   DEFINITIONS

     1.1 In this Agreement, the following terms used shall have the following
         meanings, unless otherwise specified:

     (a)  "Agreement" means this Agreement, including the schedules and
          attachments hereto, as amended from time to time, and expressions
          "herein", "hereof", "hereby", "hereunder" and similar expressions
          refer to this Agreement and not to any particular subdivision
          hereof.

     (b)  "Business Day" means a day in which both the offices of Clark and
          Koch are open for business.

     (c)  "BPD" means barrels per day.

     (d)  "Adjustment Pricing Period" means the period during the Pricing
          Period from the day after Clark elects a Supply Volume Adjustment
          and all Trading Days following, up to and including the expiration
          of the prompt NYMEX Contract.

     (e)  "Domestic Sweet Crude Oil" means hydrocarbons produced in the United
          States that are acceptable by Mid-Valley Pipeline Delivery System at
          the time of delivery as domestic sweet crude oil.

     (f)  "Injection Month" means a calendar month in which Koch injects
          Supply Volumes into the Mid-Valley Pipeline Delivery System.

     (g)  "Mid-Valley Pipeline Delivery System" means the delivery system
          consisting of the Mesa Pipeline, the West Texas Gulf Pipeline and
          the Mid-Valley Pipeline (or any successors in interest of such
          pipelines).

     (h)  "Parties" means the parties to this Agreement, namely Clark and
          Koch.

                                     -1-

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     (i)  "Pricing Period" means the period from the 26th day of the month
          prior to the expiration of the prompt New York Mercantile Exchange
          Contract ("NYMEX") for all Trading Days following, up to and
          including the expiration of the prompt NYMEX Contract.

     (j)  "Trading Day" means any day that the NYMEX light sweet crude oil
          contract is open.

2.   TERM

     2.1  This Agreement shall be effective from February 26, 1999, until such
          time as the final Supply Volumes sold under this Agreement for
          September 1999 are deemed delivered to Clark (the "Initial Term");
          and shall automatically renew for three Injection Months (the
          "Renewal Term") at the end of the Initial Term and each successive
          Renewal Term. Either Party may terminate this agreement upon three
          months written notice to the other Party, effective when the Final
          Supply Volumes from the final Injection Month are delivered. Such
          notice shall be effective no earlier than the day following the
          Initial Term.

3.   PURCHASE/QUANTITY/QUALITY/TYPE

     3.1  Clark Linefill Volumes. On March 8, 1999, Clark agrees to sell and
          deliver, and Koch agrees to purchase and receive at the Points of
          Delivery referenced in Schedule A, crude oil that Clark utilizes as
          linefill volumes on the Mid-Valley Pipeline Delivery System ("Clark
          Linefill Volumes"). Such volumes, qualities, and prices shall be
          agreed upon by the Parties for the Clark Linefill Volumes. Such
          volumes shall be determined from inventory statements from the
          pipelines of the Mid-Valley Pipeline Delivery System.

     3.2  Injection Volumes. Prior to March 8, 1999, Clark agrees to sell and
          deliver, and Koch agrees to purchase and receive at the Points of
          Delivery referenced in Schedule B, all crude oil that Clark has
          purchased and scheduled for shipment on the Mid-Valley Pipeline
          Delivery System for calendar March ("Injection Volumes"). Such
          volumes, qualities, and prices shall be agreed upon by the Parties.
          Per Schedule B, the Parties shall also agree on the volumes,
          qualities, and prices that shall apply to the sale of such Injection
          Volumes from Koch to Clark for March business.

     3.3  Supply Volumes. Following the delivery of the Injection Volumes to
          Clark, and continuing for the duration of this Agreement, Koch
          agrees to sell and deliver, and Clark agrees to purchase and receive
          a minimum of 80,000 barrels per day ("bpd") of crude oil (measured
          on a monthly average basis) at Lima, Ohio ("Supply Volumes"). Clark
          agrees to promptly nominate its Supply Volume requirements to Koch
          before the applicable Pricing Period begins. Clark also agrees to
          promptly notify Koch of a Supply Volume Adjustment (as described in
          Section 5.4) within the applicable Pricing Period.

                                     -2-
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     3.4  Koch Linefill Volumes. On the termination date of this Agreement,
          Koch agrees to sell and deliver, and Clark agrees to purchase and
          receive at the Points or Delivery and subject to the applicable
          requirements referenced in Schedule A, crude oil volumes that Koch
          utilizes as linefill volumes on the Mid-Valley Pipeline Delivery
          System at the time of such termination ("Koch Linefill Volumes").
          Such volumes shall be determined from inventory statements from the
          pipelines of the Mid-Valley Pipeline Delivery System. The Parties
          recognize that Clark may request that the Koch Linefill Volumes be
          sold to a third party that will provide crude oil supply to Clark.
          Upon such a request, the Parties will make commercially reasonable
          efforts to agree to the terms of such a sale.

4.   POINT OF DELIVERY/TITLE/RISK OF LOSS/TRANSPORTATION

     4.1  Clark Linefill Volumes. Clark shall deliver or cause to be delivered
          to Koch all the Clark Linefill Volumes deliverable pursuant to this
          Agreement by in-line transfer via the Mid-Valley Pipeline Delivery
          System (the respective "Point of Delivery"). Title to all Clark
          Linefill Volumes purchased and sold hereunder shall pass from Clark
          to Koch within the Mid-Valley Pipeline Delivery System at the time
          of such in-line transfer. Clark shall maintain risk of loss of such
          volumes.

     4.2  Injection Volumes. Clark shall deliver or cause to be delivered to
          Koch all the Injection Volumes deliverable pursuant to this
          Agreement by in-line transfer via the Mid-Valley Pipeline Delivery
          System (the respective "Point of Delivery"). Title to all Injection
          Volumes purchased and sold hereunder shall pass from Clark to Koch
          within the Mid-Valley Pipeline Delivery System at the time of
          injection of the respective Injection Volumes. Koch shall deliver or
          cause to be delivered to Clark all Injection Volumes deliverable
          pursuant to this Agreement to Lima, Ohio, via the Mid-Valley
          Pipeline Delivery System (the respective "Point of Delivery"). Title
          to all Injection Volumes purchased and sold hereunder shall pass
          from Koch to Clark as the oil passes through the Mid-Valley system
          meters exiting the Mid-Valley tank farm at Lima, Ohio, to Clark's
          facility. Clark shall maintain risk of loss of such volumes.

     4.3  Supply Volumes. Koch shall deliver or cause to be delivered to Clark
          all the Supply Volumes deliverable pursuant to this Agreement to
          Lima, Ohio, via the Mid-Valley Pipeline Delivery System (the
          respective "Point of Delivery"). Title to all Supply Volumes
          purchased and sold hereunder shall pass from Koch to Clark as the
          oil passes through the Mid-Valley system meters exiting the
          Mid-Valley tank farm at Lima, Ohio, to Clark's facility. Clark shall
          maintain risk of loss of such volumes.

     4.4  Koch Linefill Volumes. Koch shall deliver or cause to be delivered
          to Clark all the Koch Linefill Volumes deliverable pursuant to this
          Agreement by in-line transfer via the Mid-Valley Pipeline Delivery
          System (the respective "Point of Delivery"). Title to all Koch
          Linefill Volumes purchased and sold hereunder shall pass from Koch
          to Clark within the Mid-Valley Pipeline Delivery System at

                                     -3-
<PAGE>

          the time of such in-line transfer. Clark shall maintain risk of loss
          of such volumes.

     4.5  Koch Linefill Volume Adjustments. The Parties recognize that during
          the term of this Agreement, the linefill requirements on segments of
          the Mid-Valley Pipeline Delivery System ("Linefill Requirements")
          may change. If the Linefill Requirements increase during the term of
          the Agreement, Clark agrees to acquire such necessary volumes and
          enter buy/sell agreement(s) with Koch under terms substantially
          similar to those involving the Clark and Koch Linefill Volumes under
          this Agreement. If the Linefill Requirements decrease during the
          term of the Agreement, Clark agrees to purchase the relevant portion
          of the Koch Linefill Volumes under terms substantially similar to
          those involving the Clark and Koch Landfill Volumes under this
          Agreement.

     4.6  Transportation Arrangements. Koch shall use commercially reasonable
          efforts to schedule the transportation of crude oil sold to Clark,
          under, for and on behalf of Clark, to meet the needs of Clark's
          operations at Lima, Ohio. The Parties shall work with the relevant
          pipeline companies to fulfill their obligations under this
          Agreement, including passage of the historical pipeline space
          associated with the supply of Clark's Lima refinery from Clark to
          Koch at the beginning of the term of this Agreement, and from Koch
          to Clark upon its termination. Koch shall utilize Clark's
          transportation options with UNOCAL on the Mesa Pipeline, if the
          terms of such arrangement are agreeable to Koch.

     4.7  Exclusive Supplier. Clark shall utilize Koch as Clark's exclusive
          supplier of crude oil and condensate on the Mid-Valley Pipeline
          Delivery System.

5.   PRICE

     5.1  Clark and Koch Linefill Volumes. The price payable by Koch for the
          Clark Linefill Volumes and price payable by Clark for Koch Linefill
          Volumes shall be per Schedule A.

     5.2  Injection Volumes. The price payable by Koch for the Injection
          Volumes shall be per Schedule B.

     5.3  Supply Volumes. Subject to Supply Volume Adjustment as addressed in
          Section 5.4, the price payable per barrel by Clark for the Supply
          Volumes shall be determined according to the formula described and
          defined below.

          (a)  Monthly Supply Volume Price Formula (See Schedule D for sample
               calculation)

               SVP = C + T + P + E + TF

                                     -4-
<PAGE>

                 Where:
                      SVP      =    Monthly Supply Volume Price ($/bbl)
                      C        =    Calendar NYMEX Average ($/bbl)
                      T        =    Timing Adjustment ($/bbl)
                      P        =    Platt's Midland Adjustment ($/bbl)
                      E        =    EFP Adjustment ($/bbl)
                      TF       =    Transportation and Fee Adjustment ($/bbl)

          (b)  Definitions

               1)   Calendar NYMEX Average. The Calendar NYMEX Average is
                    defined as a price equal to the arithmetic daily average
                    of the NYMEX Light Sweet Crude Oil Futures contract
                    settlement price for the prompt month contract during the
                    calendar month of injection, Trading Days only.

               2)   Timing Adjustment. The Timing Adjustment is defined as the
                    arithmetic daily average of approximately two thirds (see
                    table below for exact split by Injection Month) of the
                    difference between the settlement prices of the first
                    nearby contract, and the second nearby contract plus
                    approximately one third (see table below) of the difference
                    between the settlement prices of the first nearby contract
                    and the third nearby contract over the Pricing Period for
                    the associated Injection Month. The Trading Day split for
                    each trading month shall be determined by the number of
                    days for which each of the associated nearby contracts
                    is/are open during the actual Injection Month.

                           April 1999             13 / 8
                            May 1999              14 / 6
                           June 1999              16 / 6
                           July 1999              13 / 8
                          August 1999             15 / 7
                         September 1999           14 / 7

                    *    Based on the NYMEX Expiration Date for Each Calendar
                         Month Trading Days Only.

                  Pricing Example:  Injection Month of April

                  Timing Adjustment Formula {[(13/21)*(April - May)] +
                  [(8/21)*(April - June)]}

               3)   Platt's Midland Adjustment. The Platt's Midland Adjustment
                    is defined as the average differential for Domestic Sweet
                    Crude Oil assessed for delivery at Arco Midland, and
                    Domestic Sweet Crude Oil assessed for delivery at Arco
                    Cushing, each based on the mean of the daily high and low
                    published prices, for all reported Trading Days during the
                    Pricing Period as published in Platt's Spot Crude Price
                    Assessments for the first NYMEX Light Sweet Crude Oil
                    contract month corresponding with the

                                     -5-
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                    actual Injection Month, Trading Days only. As an example
                    for April Injection Month, the Platt's Midland Adjustment
                    would be calculated February 26, 1999, through and
                    including March 22, 1999.

               4)   EFP Adjustment. The EFP Adjustment shall be mutually
                    agreed upon on a monthly basis prior to nomination of
                    Supply Volumes pursuant to Schedule C. If the Parties
                    cannot agree to an EFP adjustment, Koch shall execute an
                    EFP in the marketplace. The value of such EFP shall be
                    used as the EFP Adjustment for the relevant time period.

               5)   Transportation and Fee Adjustment. The Transportation and
                    Fee Adjustment is defined as the total cost to transport
                    barrels from Arco Midland to Lima, Ohio, including all
                    associated pipeline tariff costs, fees, and other charges
                    as specifically described in Schedule C.

          (c)  Should the Parties mutually agree, alternate grades (domestic
               or foreign) can be delivered instead of the Domestic Sweet
               Crude Oil common stream. The pricing of these alternate grades
               will utilize the Monthly Supply Volume Price formula adjusted
               by a price differential mutually agreed to by both parties. For
               example, should both Parties agree to the delivery of 500MB of
               Bonny Light crude at an agreed premium of $0.20/barrel, the
               invoice price for the month(s) during which the Bonny Light is
               delivered to Lima, Ohio, will be adjusted up from the standard
               price formula by a total of $100M (500MB x 0.20$/bbl). Koch
               will arrange for importation of foreign barrels.

     5.4  Supply Volume Adjustment. If during the Pricing Period, for a
          calendar month of Supply Volume injections, Clark elects to adjust
          the Supply Volumes that Clark nominates for such month ("Supply
          Volume Adjustment") and such adjustment is approved by Koch, the
          price payable for those Supply Volumes shall be determined according
          to the following formula described and defined below:

          (a)  Monthly Supply Volume Adjustment (See Schedule D for sample
               calculation)

                      SVPF = SVP(VT) + SVPA(VA)
                             ------------------
                                 VT + VA

                      Where:

                      SVPF = Final Monthly Supply Volume Price in a Supply
                             Volume Adjustment month ($/bbl)
                      SVP  = Monthly Supply Volume Price ($/bbl)
                      VT   = The total Supply Volumes Clark nominates with Koch
                             for the relevant calendar month (bbl)

                                     -6-
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                      SVPA = Price for adjusted volumes in a Supply
                             Volume Adjustment month ($/bbl)
                      VA   = The total Supply Volumes that Clark elects to
                             add to or subtract from the nominated Monthly
                             Supply Volumes (expressed as a positive (+) number
                             if Clark elects to add and expressed as a
                             negative (-) number if Clark elects to
                             subtract)

                      SVPA = CA + TA + PA + EA + TFA

                      Where

                      CA  = Calendar NYMEX Average for a Supply Volume
                            Adjustment Month ($/bbl)
                      TA  = Timing Adjustment for a Supply Volume Adjustment
                            Month ($/bbl)
                      PA  = Platt's Midland Adjustment for a Supply
                            Volume Adjustment Month ($/bbl)
                      EA  = EFP Adjustment for a Supply Volume Adjustment Month
                            ($/bbl)
                      TFA = Transportation and Fee Adjustment for a Supply
                            Volume Adjustment Month ($/bbl)

          (b)  Definitions

               1)   Calendar NYMEX Average. The Calendar NYMEX Average is
                    defined as a price equal to the arithmetic daily average
                    of the NYMEX Light Sweet Crude Oil Futures contract
                    settlement price for the prompt month contract during the
                    calendar month of injection, Trading Days only.

               2)   Timing Adjustment. The Timing Adjustment for a Supply
                    Volume Adjustment Month is defined as the arithmetic
                    daily average of approximately two thirds (see table below
                    for exact split by Injection Month) of the difference
                    between the settlement prices of the first nearby contract
                    and the second nearby contract plus approximately one
                    third (see table) of the difference between the settlement
                    prices of the first nearby contract and the third nearby
                    contract over the Adjustment Pricing Period for the
                    associated Injection Month. The Trading Day split for each
                    trading month shall be determined by the number of days
                    for which each of the associated nearby contract is open
                    during the actual Injection Month.

                        April 1999                  13 / 8
                         May 1999                   14 / 6
                        June 1999                   16 / 6
                        July 1999                   13 / 8
                       August 1999                  15 / 7
                      September 1999                14 / 7

                                     -7-
<PAGE>

                       * Based on the NYMEX Expiration Date for Each Calendar
                         Month Trading Days Only.

                  Pricing Example:  Injection Month of April

                  Timing Adjustment Formula {[(13/21)*(April - May)] +
                                             [(8/21)*(April - June)]}

               3)   Platt's Midland Adjustment. The Platt's Midland Adjustment
                    Average for a Supply Volume Adjustment Month is defined as
                    the average differential for Domestic Sweet Crude Oil
                    assessed for delivery at Arco Midland and Domestic Sweet
                    Crude Oil assessed for delivery at Arco Cushing each based
                    on the mean of the daily high and low published prices,
                    for all reported Trading Days during the Adjustment
                    Pricing Period as published in Platt's Spot Crude Price
                    Assessments for the first NYMEX Light Sweet Crude Oil
                    contract month corresponding with the actual Injection
                    Month, Trading Days only.

               4)   EFP Adjustment. The EFP Adjustment shall be mutually
                    agreed upon prior to the nomination of the Supply Volume
                    Adjustment pursuant to Schedule C. If the Parties cannot
                    agree to an EFP adjustment, Koch shall execute an EFP in
                    the marketplace. The value of such EFP shall be used for
                    the relevant time period.

               5)   Transportation and Fee Adjustment. The Transportation and
                    Fee Adjustment is defined as the total cost to transport
                    barrels from Arco Midland to Lima, Ohio, including all
                    associated pipeline tariff costs, fees, and other charges
                    as specifically described in Schedule C.

     5.5  For pricing purposes, all Supply Volumes injected into the
          Mid-Valley Pipeline Delivery System in a calendar month will be
          priced (per barrel) pursuant to the applicable Monthly Supply Volume
          Price Formula (in Sections 5.3 and 5.4) for that calendar month,
          without regard to when such Supply Volumes are delivered or paid for
          under the terms of this Agreement. An example follows:

          Assume that during April 1999, Koch injects 2.4 million barrels of
          Supply Volumes into the Mid-Valley Pipeline Delivery System for sale
          and delivery to Clark. Of those 2.4 million barrels of Supply
          Volumes, 2.0 million are delivered to Clark during April and 0.4
          million are delivered during May. Assume also that Koch injects 2.6
          million barrels of Supply Volumes during May, of which 2.1 million
          barrels are delivered during May and 0.5 million barrels are
          delivered during June. Pursuant to this Section and the payment
          provisions in Section 6, Clark would pay Koch for the 2.0 million
          barrels of Supply Volumes based on the Monthly Supply Volume Price
          formula for April by the 20th of May. Clark would pay Koch for the
          0.4 million barrels of Supply Volumes based on the Monthly Supply
          Volume Price formula for April by the 20th of June. Furthermore,
          Clark would pay Koch for the 2.1 million barrels of Supply Volumes
          based on the Monthly Supply Volume Price formula for May by the 20th
          of June. Clark would

                                     -8-
<PAGE>

          also pay Koch for the 0.5 million barrels of Supply Volumes based on
          the Monthly Supply Volume Price formula for May, in addition to
          Supply Volumes injected and delivered in June and based on the
          Monthly Supply Volume Price formula for June, by the 20th of July.

     5.6  Supply Volume Adjustments after the Pricing Period. After the
          Pricing Period for a calendar month of Supply Volume injections,
          Clark may adjust the Supply Volumes that Clark nominates for such
          month only upon agreement between the Parties on all the terms of
          such adjustment, including, but not limited to, price.

     5.7  Pipeline Loss Allowance. Koch shall be entitled to charge Clark for
          pipeline loss allowances as incurred by Koch due to shipping Supply
          Volumes to Clark on the Mid-Valley Pipeline Delivery System when
          such pipeline loss allowance costs are incurred by Koch.

6.   PAYMENT

     6.1  Koch shall invoice Clark promptly after the end of each month for
          deliveries made during that month and, subject to Section 6.2,
          payment shall be made by Clark by the twentieth (20th) day of the
          month following delivery. Payment shall be wired to Koch's bank
          account according to Koch's invoice instructions, or by any other
          acceptable payment method as mutually agreed upon.

          Clark shall invoice Koch promptly after sale of the Linefill and
          Injection Volumes for deliveries made during the relevant month.
          Subject to Section 6.2, payment shall be made for the Linefill
          Volumes by Koch on March 8, 1999, and for the March Injection
          Volumes on April 20, 1999. Payment shall be wired to Clark's bank
          account, or by any other acceptable payment method as mutually
          agreed upon.

     6.2  If the date for payment of any monies under this Agreement falls on
          a Saturday or on a bank holiday other than Monday during which New
          York Banks are closed for normal business transactions, then payment
          shall be due on the first (1st) previous day on which the New York
          Banks are open for normal business transactions. If the date for
          payment of any monies under this Agreement falls on a Sunday or a
          Monday bank holiday, then payment shall be due on the next day on
          which the New York Banks are open for normal business transactions.

     6.3  All respective invoices shall be forwarded promptly to:

            Clark Refining and Marketing, Inc.
            Attn:  Crude Oil Accounts Payable (Joe Leach)
            8182 Maryland Avenue
            St. Louis, Missouri 63105

            Facsimile Number: (314) 854-1580

            Koch Petroleum Group, L.P.
            Attn:  Accounts Payable, Dana Bruggeman
            P.O. Box 2256
            Wichita, Kansas 67201-2256

            Facsimile Number: (316) 828-6868

                                     -9-
<PAGE>

     6.4  If either Party disputes the amount of any invoice provided by the
          other Party, it shall notify the other Party promptly of such
          disagreement including particulars thereof.

     6.5  Credit Requirements. As a condition precedent to this Agreement,
          Clark agrees to establish an irrevocable standby letter of credit in
          a format acceptable to Koch. The letter of credit shall be issued by
          a first class bank acceptable to Koch. All banking charges related
          to this letter of credit are for Clark's account. The letter of
          credit shall be received by Koch three (3) business days prior to
          the first day of the delivery date range.

7.   TITLE AND WARRANTIES

     7.1  Clark warrants clear title to all crude oil delivered hereunder and
          that the same is free from all liens, encumbrances and all
          applicable taxes and royalties. Clark additionally warrants that
          Clark has the exclusive right to receive payment, unless Clark
          advises to the contrary, in full for all crude oil sold or to be
          sold hereunder by Clark. Clark agrees to indemnify and hold Koch
          harmless against any and all loss, cost, damage and expense incurred
          by reason of any failure of title to the extent of such warranty in
          accordance with Section 9.1.

     7.2  Clark represents and warrants that it has provided notice to Bankers
          Trust Company that Clark has sold the Clark Linefill Volumes and
          Injection Volumes to Koch and, accordingly, has reduced its current
          borrowing base with Bankers Trust Company to reflect the sale of
          such volumes to Koch. Furthermore, Clark covenants and agrees that
          it shall not include the Koch Linefill Volumes or Injection Volumes
          (while owned by Koch) in its borrowing base with Bankers Trust
          Company or any other lender at any time during the term of this
          Agreement, or thereafter, until the respective volumes are sold to
          Clark pursuant to Sections 3.2 and 3.4 hereof.

     7.3  Clark represents and warrants that Clark has secured insurance
          against all risks of loss including contamination and shortage,
          howsoever caused, to cover the full fair market value of the
          Injection Volumes, Clark/Koch Linefill Volumes and Supply Volumes.
          Clark further agrees to list Koch as a loss payee for such
          insurance.

     7.4  The Parties make no other warranty, expressed or implied, concerning
          the crude oil purchased and sold hereunder other than it shall meet
          the specifications of the applicable carrier and this Agreement.

                                     -10-
<PAGE>

8.   TAXES

     8.1  Clark shall be liable for all taxes imposed on the crude oil prior
          to delivery to Koch and after delivery to Clark.

9.   LIABILITY AND INDEMNITY

     9.1  Clark undertakes to defend, indemnify and save Koch harmless from
          any and all liability, litigation, action, cause of action, dispute,
          claim, costs and expenses, penalties, debt or demand and all loss or
          damage whatsoever arising out of or in any way connected to the
          title to the Linefill, Injection, or Supply Volumes delivered under
          this Agreement, unpaid royalties, taxes or any other charges, liens
          and encumbrances against any of such Volumes sold hereunder,
          environmental contamination related to any such Volumes, and the
          purchase, transportation and sale of such Volumes.

     9.2  Clark shall compensate Koch for all damages Koch incurs related to
          any inability of Koch to acquire or deliver or Clark to receive
          crude oil under this Agreement (including, but not limited to,
          proration on the Mid-Valley Pipeline Delivery System, operational
          difficulties at Clark's facilities and operational difficulties on
          the Mid-Valley Pipeline System) and for all damages Koch incurs
          related to the loss of or damage to any Linefill, Injection or
          Supply Volumes.

     9.3  Except as specified in Section 9.2, neither Clark nor Koch shall be
          liable to the other for loss of prospective profits or special,
          indirect or consequential damages.

10.  APPLICATION OF LAW

     10.1 This Agreement shall be interpreted in accordance with and governed
          by the laws of the State of Texas.

11.  FORCE MAJEURE

     11.1 In the event of the occurrence of a Force Majeure event which
          prevents Koch's performance hereunder, Koch shall be relieved of any
          obligation or liability under the terms of this Agreement until the
          expiration of a reasonable time after termination of such
          disability.

     11.2 "Force Majeure" means an event which is unforeseen and beyond the
          control of the party that either prevents the party from delivering
          the affected volume or prevents the party from accepting delivery of
          the affected volume. The following are the only instances that will
          be recognized as Force Majeure events hereunder: earthquakes;
          floods; landslides; civil disturbances; sabotage; acts of public
          enemies; war; blockades; insurrections; riots; epidemics; the act of
          any government or other authority or statutory undertaking; the
          inability to obtain or the curtailment of electric power, water or
          fuel; strikes, lockouts or other disruptions; fires; explosions;
          breakdowns or failure of pipe, plant, machinery or

                                     -11-
<PAGE>

          equipment; and contamination or poisoning of catalyst and/or solvent
          or biological treatment facilities.

     11.3 For greater certainty, a lack of funds or the availability of a more
          attractive market do not constitute events of Force Majeure.

     11.4 Koch agrees to notify Clark of the occurrence of the Force Majeure
          event as soon as possible, but in any event within two (2) Business
          Days.

12.  NOTICES

     12.1 Any notice permitted or required to be given under this Agreement
          shall be in writing, either delivered, mailed or sent via
          telecommunication and shall be addressed to the parties hereto as
          follows:

           Clark:        Clark Refining and Marketing, Inc.
                         Attention: John Overbey
                         8182 Maryland Avenue
                         St. Louis, Missouri 63105

                         Facsimile No.: (314) 854-9635

           Koch:         Koch Petroleum Group, L.P.
                         Attention: Brad Urban
                         4111 E. 37th St. N.
                         Wichita, Kansas 67220

                         Facsimile No.: 316-828-7977

     12.2 Any notice shall:

          i)   if delivered, be deemed to have been given or made at the time
               of delivery as acknowledged by signature of the receiving party;
               and/or

          ii)  if sent by facsimile, telex, telecommunication device or other
               similar form of communication, be deemed to have been given or
               made on the working day following the day on which it was sent;
               and/or

          iii) if mailed, be deemed to have been given or made, four (4) days
               after the postmarked date thereof.

13.  ASSIGNMENT

     13.1 Either party may assign this Agreement in whole or in part to an
          Affiliate or may cause any or all of its obligations to be performed
          by an Affiliate. Any attempt by either party to assign its rights or
          delegate its duties under this Agreement in whole or in part to a
          non-affiliate without the prior written consent of the other party,
          such consent not to be unreasonably withheld, shall be ineffective.

                                     -12-
<PAGE>

     13.2 "Affiliate" means a corporation or partnership that is affiliated
          with the party in respect of which the expression is being applied,
          and, for the purpose of this definition:

          (a)  a corporation or partnership is an "Affiliate" of another
               corporation or partnership if it directly or indirectly
               controls or is controlled by that other corporation or
               partnership, and for the purpose of determining whether a
               corporation or partnership so controls or is so controlled, it
               shall be deemed that

               (i)  a corporation is directly controlled by another
                    corporation or partnership if shares of the corporation to
                    which are attached more than 50% of the votes that may be
                    cast to elect directors of the corporation are
                    beneficially owned by that other corporation or
                    partnership and the votes attached to those shares are
                    sufficient, if exercised, to elect a majority of the
                    directors of the corporation;

               (ii) a partnership is directly controlled by a corporation or
                    another partnership if that corporation or other
                    partnership beneficially owns more than a 50% interest in
                    the partnership;

               (iii) a corporation or partnership is indirectly controlled by
                    another corporation or partnership if control, as defined
                    in a (i) or (ii) above, as the case may be, is exercised
                    through one or more other corporations or partnerships;
                    and

          (b)  where two or more corporations or partnerships are affiliated
               at the same time with the same corporation or partnership, they
               shall be deemed to be an "Affiliate" of each other.

14.  GENERAL

     14.1 Entire Agreement. This Agreement and the attached Koch Petroleum
          Group Crude Oil Purchase General Provisions constitute the entire
          agreement between the parties with respect to the sale of crude oil
          hereunder and supersedes all prior negotiations and agreements
          thereto, written or oral. Where the General Provisions are
          inconsistent with the specific provisions of this Agreement, this
          Agreement shall control.

     14.2 Amendments. Unless otherwise provided herein, no changes, alteration
          or modifications to this Agreement shall be effective unless in
          writing and signed by the respective duly authorized representatives
          of the parties hereto.

     14.3 Headings. The headings in this Agreement are for convenience only
          and shall not be considered in the interpretation of the Agreement.

     14.4 Industry Practices. This Agreement shall be construed in accordance
          with accepted oil industry terminology and practices.

                                     -13-
<PAGE>

     14.5 Severability. If any provision or any portion of any provision of
          this Agreement or the application of any such provision or any
          portion thereof to any person or circumstance, is held invalid or
          unenforceable, the remaining portion of such provision and the
          remaining provisions shall remain in full force and effect.

So agreed on this 8th day of March, 1999.

KOCH PETROLEUM GROUP, L.P.                CLARK REFINING & MARKETING, INC.
by KPG/GP, Inc., its General Partner
                                          By: /s/ John Overbey
By: /s/ Jim Imbler                            ------------------------
   ----------------------                 Printed Name: John Overbey
Printed Name: Jim Imbler                  Title: Vice President Crude
Title: President                                 Oil Supply

By: /s/ Seth Vance
   ----------------------
Printed Name: Seth Vance
Title: Executive VP/Chief
       Operating Officer

                                     -14-

<PAGE>

                             KOCH PETROLEUM GROUP
                              CRUDE OIL PURCHASE
                              GENERAL PROVISIONS

1.   MEASUREMENT AND TESTS: All measurements of crude oil and/or condensate
     (collectively "crude oil") purchased and delivered hereunder shall
     represent one hundred percent (100%) volume, consisting of United States
     barrels of forty-two (42) gallons, the quantity and gravity of which will
     be adjusted to sixty degrees (60) Fahrenheit temperature. Procedures for
     measuring and testing, except for delivery through positive displacement
     type meters, shall be computed in accordance with the latest ASTM
     published methods then in effect. Procedures for meter type deliveries
     shall be in accordance with the latest ASME-API (Petroleum PD Meter Code)
     published methods then in effect, or other mutually agreeable method. The
     crude oil delivered hereunder shall be merchantable and acceptable to the
     carriers involved but not to exceed one percent (1%) BS&W and full
     deduction shall be made for all BS&W content according to the ASTM
     Standard Method then in effect. Should either party hereto fail to have a
     representative present during such measuring and testing, the measurement
     and tests of the other party shall be accepted,

2.   PAYMENT: Unless specifically stated otherwise in the agreement to which
     these General Provisions are attached, Buyer agrees to make payment to
     Seller for the crude oil purchased and delivered hereunder not later than
     the 20th day of the month following the month of delivery. If payment is
     made by wire transfer and the 20th day of the month falls on a Saturday
     or a New York Bank Holiday other than a Monday, payment shall be due on
     the immediately preceding New York Banking Day. If payment is made by
     wire transfer and the 20th day of the month falls on a Sunday or a Monday
     New York Bank Holiday, payment shall be due on the next succeeding New
     York Banking Day. If payment is made by check and the 20th day of the
     month falls on a Saturday, the check will be mailed on that Saturday. If
     payment is made by check and the 20th day falls on a Sunday, the check
     will not be mailed until the following Monday, unless that Monday is a
     New York Bank Holiday, in which event the check will be mailed on the
     next succeeding New York Banking Day.

     If the financial responsibility of Buyer at any time becomes impaired,
     unsatisfactory, or unacceptable to Seller, or if sales to Buyer by Seller
     exceed approved credit lines, Buyer shall secure and deliver to Seller
     such advance payments or other security, including in appropriate
     instances an acceptable letter of credit, as required by Seller, and
     deliveries of crude oil hereunder may be withheld until such security is
     received. If such security is not received within the time specified by
     Seller, then Seller shall have the right to cancel this agreement.

3.   RULES AND REGULATIONS: All of the terms and provisions of this agreement
     shall be subject to the applicable orders, rules and regulations
     (hereinafter generically referred to as "Regulations") of all
     governmental authorities having or purporting to have jurisdiction in the
     premises. If at any time or from time to time such regulations should be
     amended or should new regulations be adopted and the effect of such
     amended or new regulation (a) is not covered by any other provision of
     this agreement and (b) has an adverse economic effect upon either party
     hereto or its suppliers or customers, the party affected shall have the
     option to request renegotiation of the prices and other pertinent terms
     provided for in this agreement. Said option may be exercised by such
     party at any time after such amended or new regulation is promulgated

                                     -15-
<PAGE>

     by giving written notice of the desire to renegotiate prior to the time
     of delivery of the crude oil, such notice to contain the new prices and
     terms desired by the affected party. If the parties do not agree upon new
     prices and terms satisfactory to both within (30) days after such notice
     is given, the affected party shall have the right to terminate this
     agreement at the end of said thirty (30) day period.

4.   ASSIGNMENT: Neither party shall assign this agreement or any rights
     hereunder without first obtaining the written consent of the other party
     hereto.

5.   SAFETY: Each party agrees that its agents and employees will comply with
     all known safety regulations of the other when such agents or employees
     are upon the premises of the other in connection with the performance of
     this agreement.

6.   BUSINESS PRACTICES: Each party hereto agrees to comply with all laws and
     regulations applicable to activities carried out in the name of or on the
     behalf of the other party under provisions of this agreement.

     Each party hereto agrees that all financial settlements, billings and
     reports rendered to the other party as provided for in this agreement
     will, to the best of its knowledge, reflect properly the facts about all
     activities and transactions related to this agreement.

     Each party agrees to notify the other party promptly upon discovery of
     any instance where the notifying party fails to comply with either
     provision above or whose conduct by the notified party is considered, by
     the notifying party, to be in breach of this agreement.

7.   ADDITIONAL TERMS. No waiver by either party hereto of a breach of an
     obligation owed hereunder by the other party shall be construed as a
     waiver of any other breach, whether of the same or a different nature.

     Any provision hereof which is legally unenforceable shall be ineffective
     only to the extent of such unenforceability without thereby invalidating
     the remaining provisions hereof or affecting the validity of
     enforceability of this agreement as a whole.

     This agreement contains the entire agreement between the Seller and Buyer
     with respect to the subject matter hereof, and there are no other
     premises, representations, or warranties affecting it. The specific
     provisions to which these General Provisions are attached govern these
     General Provisions in the event of any conflict between the two.

     This agreement shall not be modified or amended except by written
     instrument duly executed by officers or other duly authorized
     representatives of the respective parties.

                                     -16-
<PAGE>

                                 SCHEDULE "A"
                        Clark and Koch Linefill Volumes
<TABLE>
<CAPTION>

CLARK LINEFILL VOLUMES

Location/Point of Delivery    Volume (bbl)              Quality/Type                Price
--------------------------    ------------              ------------                -----

<S>                             <C>                  <C>                        <C>
Mesa Pipeline                     567,399*           Common Stream Sweet        $12.56 - $0.25 / bbl [Average
                                                                                of NYMEX settlements for
                                                                                March 1, 2, 3 for April WTI]

West Texas Gulf Pipeline          922,812*           Common Stream Sweet        $12.56 - $0.15 / bbl
                                                                                [Average of NYMEX
                                                                                settlements for March 1, 2, 3
                                                                                for April WTI]

Mid-Valley Pipeline             1,648,160*           Common Stream Sweet        $12.56 + $0.10 / bbl
                                                                                [Average of NYMEX
                                                                                settlements for March 1, 2, 3
                                                                                for April WTI]
</TABLE>

* These Volumes are listed provisionally to be adjusted once pipeline data for
  inventories on March 8, 1999, is available.

                                     A-1
<PAGE>

KOCH LINEFILL VOLUMES
Note:  Should this Contract be renewed, the terms of the Sale of the Koch
       Linefill Volumes will be renegotiated and agreed to by the parties.

Location/Point           Volume
 of Delivery              (bbl)     Quality/Type                 Price**
 -----------              -----     ------------                 -------

Mesa Pipeline                *     Common Stream Sweet      A - $0.25 - B + C

West Texas Gulf Pipeline     *     Common Stream Sweet      A - $0.15 - B + C

Mid-Valley Pipeline          *     Common Stream Sweet      A + $0.10 - B + C

*  These Volumes are to be the same as the final Clark Linefill Volumes as
   adjusted above unless additional buy/sells have taken place due to linefill
   requirement changes by the relevant pipeline companies pursuant to Section
   4.5 of this Agreement.

** Price Formula

         Note: It is assumed that the sale of Koch Linefill Volumes to Clark
         will take place in mid-October 1999, unless this Agreement is
         renewed. Prices for such sale will be priced using the following
         variables:

         A = Average of NYMEX settlements for October 13, 14, and 15, 1999, WTI.

         B = Contango Credit.

          Note: As Koch buys April WTI and sells November WTI, there is a
          "Contango Credit" which will be applied for Clark's benefit. The
          Parties agree that Clark should received the benefit of the Contango
          Credit since it is value that Clark holds at the time the Clark
          Linefill Volumes are sold to Koch. At the time of this Agreement,
          the Contango Credit is worth approximately $0.7233 per barrel.

          C = $0.02 per barrel for Execution and Margin Costs.

                                     A-2

<PAGE>

                                 SCHEDULE "B"
                               Injection Volumes

Injection Volumes sold to Koch
                                    Volume                             Price
   Location/Point of Delivery      (bbl/day)    Quality/Type          ($/bbl)
   --------------------------      ---------    ------------          -------
Mesa Pipeline System                 24,405   Common Stream Sweet     12.00

West Texas Gulf System

   Colorado City                      3,175   Common Stream Sweet     12.00

   Wortham                              400   Common Stream Sweet     12.00

Mid-Valley Pipeline System

   East Texas Mainline at Longview    8,800   Quaiboe                 12.00

Injection Volumes sold to Clark
                                    Volume                             Price
   Location/Point of Delivery      (bbl/day)    Quality/Type          ($/bbl)
   --------------------------      ---------    ------------          -------

Mesa Pipeline System                 24,405   Common Stream Sweet   12.00 + TFA*

West Texas Gulf System                        Common Stream Sweet

   Colorado City                      3,175   Common Stream Sweet   12.00 + TFA*

   Wortham                              400   Common Stream Sweet   12.00 + TFA*

Mid-Valley Pipeline System

   East Texas Mainline at Longview    8,800   Quaiboe               12.00 + TFA*

*See Schedule C for Injection Volume TFA value

                                     B-1
<PAGE>

                                 SCHEDULE "C"
                              TFA and EFP Values

TRANSPORTATION AND FEE ADJUSTMENT

NYMEX Calendar Simulation
Floor Broker, Clearing and Margin
  Finance                                      0.0200           0.0200
Cash Broker to buy Midland                     0.0050           0.0050
Buy Midland/Sell Cushing:
Midland ILT Fee                                0.0065           0.0065
Cushing ILT Fee                                0.0065           0.0065
Arco/Chevron Pumpover at Midland               0.0800           0.0800
Mesa Tariff (first 27,500 MBD/Unocal)*                          0.0490*
Mesa Tariff (all other shipments)              0.0917
WTG Tariff                                     0.2488           0.2488
MidValley Tariff                               0.5629           0.5629

Service Fee                           0.2370**/0.1100***        0.2370**

Total (US$/bbl)                       1.2584**/1.1314***        1.2157*

* This tariff rate and total shall apply to the first 27,500 bpd only if Koch
  agrees to utilize Clark's transportation option on UNOCAL pursuant to Section
  4.6 of this Agreement.

** This service fee and total shall apply to the first 80M bpd injected during
   any Injection Month.

*** This service fee and total shall apply to any volumes injected in excess
    of 80M bpd in any Injection Month.

EFP ADJUSTMENT TABLE

EFP                                               0.0200
EFP broker fee                                    0.0050
EFP inline fee at Cushing                         0.0065

Total (US$/bl)                                    0.0315

                                     C-1
<PAGE>

INJECTION VOLUME TRANSPORTATION AND FEE
ADJUSTMENT

NYMEX Calendar Simulation
Floor Broker, Clearing and Margin Finance          N/A           N/A
Cash Broker to buy Midland                         N/A           N/A
Buy Midland/Sell Cushing:
Midland ILT Fee                                    N/A           N/A
Cushing ILT Fee                                    N/A           N/A
Arco/Chevron Pumpover at Midland **             0.0800        0.0800
Mesa Tariff (first 27,500 MBD/Unocal) */**                    0.0490
Mesa Tariff (a11 other shipments) **            0.0917

WTG Tariff **                                   0.2488        0.2488
MidValley Tariff **                             0.5629        0.5629

Service Fee                                     0.0400        0.0400

Total (US$/bbl)                                 1.0234       0.9807*

* This tariff rate and total shall apply to the first 27,500 bpd only if Koch
  agrees to utilize Clark's transportation option on UNOCAL pursuant to Section
  4.6 of this Agreement.

** It remains to be determined which Party will be invoiced for March
   shipments. Should Koch be invoiced, the relevant pipeline charges will be
   applied.

                                     C-2
<PAGE>

                                 SCHEDULE "D"
                MONTHLY SUPPLY VOLUME PRICE SAMPLE CALCULATIONS

I.   Example Calculation - Monthly Supply Volume Price (April 1999) without
     Supply Volume Adjustment

         Assume the following:
         C = $12.50
         T = $-0.1881

             Where:     April - May = $-0.15
                        April - June = $-0.25
                        T = $-0.1881 = {(13/21)*(-0.15)]+[(8/21)*(-0.25)]}

         P = $-0.25
         E = $0.0315
         TF = $1.2584

SVP (April 1999) = $13.3518/bbl = $12.5000 + $-0.1881 + $-0.2500 + $0.0315 +
$1.2584

II.  Example Calculation - Monthly Supply Volume Price (April 1999) with
     Supply Volume Adjustment

         Assume the following:

          *Clark advises Koch on 3/15 of election for Supply Volume Adjustment
           from 2.4mm bbls to 1.8mm bbls for April 1999

         SVP (April 1999) = $13.3518/bbl
         VT = 2.4 mm bbls
         VA = -0.6 mm bbls
         SVPA = $13.1137 = $12.50 + $-0.3262 + $-0.35 + $0.0315 + $1.2584

            Where:  CA= $12.50
                    TA = $-0.3262

                    Where:  April - May (3/16-3/22 Avg. Values) = $-0.25
                            April - June (3/16-3/22 Avg. Values) = $-0.45
                            TA = $-0.3262 = {(13/2l)*(-0.25))+[(8/2l)*(-0.45)]}

                    PA = $-0.35
                    EA = $0.0315
                    TFA = $1.2584

SVPF (April 1999) = $ 13.4312/bbl =

                    ($13.3520)(2,400,000) + ($13.1137)(-600,000)
                     --------------------------------------------
                                 2,400,000 + -600,000

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00030-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00030-of-00352.parquet"}]]