<PAGE>   1
                                                                    EXHIBIT 10.7


                         PRODUCTS TERMINALLING AGREEMENT

         This Products Terminalling Agreement ("Agreement") is made between
Williams Terminal Holdings, L.L.C., a Delaware limited liability company, whose
address is P.O. Box 3448, MD 720-A, Tulsa, Oklahoma 74101 ("Williams") and
Williams Energy Marketing and Trading a Delaware corporation whose address is
One Williams Center, Tulsa, OK 74101 ("Customer"), and is effective as of
September 16, 1999. In accordance with this Agreement, Williams desires to
provide certain terminalling services to Customer in Williams's tankage, and
Customer desires to utilize such facilities for storing petroleum product(s),
all as set forth below. Accordingly, the parties agree as follows:

I.       AGREEMENT. This Agreement shall be comprised of, and the parties shall
         be bound by, these signed terms and conditions and Schedule A -
         Business Terms (the "Business Terms"), Schedule B - Product
         Terminalling General Terms, and Schedule C - Marine Terminalling
         Provisions", which are attached hereto and incorporated herein. In the
         event of conflicts, the Schedules A and C shall be subordinate to
         Schedule B. Each of the persons and parties signing this Agreement
         represents that it has full power and authority to enter into and
         perform this Agreement, that the signing and delivery of this Agreement
         has been duly authorized by all necessary corporate action of such
         party, and that this Agreement constitutes the valid and binding
         obligation of such party. This Agreement shall only be binding when
         signed below by both of the parties.

II.      SERVICES. Williams agrees to provide the terminalling services
         described below, and other necessary facilities and services for the
         receipt, storage and handling of Customer's products, at its Galena
         Park terminal facilities at Galena Park, TX (the "Terminal"). Williams
         agrees to keep the Terminal open for the handling of Customer's
         products twenty-four (24) hours a day, seven (7) days a week.

         PRODUCT: Gasoline, Gasoline Blend Components, Diesel, Jet A1, clean
         condensate, distillate blendstocks, and such other products as may be
         agreed by the parties (the "Product").

         DELIVERY BY CUSTOMER: Into Customer's Tankage at the Terminal via
         Customer's nominated marine vessel acceptable to Williams, via
         pipeline, tank truck (if agreed by Williams), and/or via tank-to-tank
         transfer from other parties within the Terminal.

         DELIVERY BY WILLIAMS: To pipeline, to Customer's nominated marine
         vessel acceptable to Williams, pipeline, tank truck (if agreed by
         Williams), and/or to other parties within the Terminal via tank-to-tank
         transfer.

         PRODUCT BLENDING: If both parties agree in writing, the Terminal shall
         follow Customer's specific written instructions, subject to limitation
         by available facilities and equipment within the Terminal, to blend, at
         no additional cost to Customer beyond the charges set out in Section
         III of these Business Terms, different gasoline components in one or
         more tanks within the Terminal for the purpose of achieving a finished
         gasoline commodity. CUSTOMER SHALL HOLD HARMLESS AND INDEMNIFY WILLIAMS
         FOR AND AGAINST ANY LIABILITY FOR ANY LOSS OR DAMAGE

<PAGE>   2


         RESULTING FROM SUCH BLENDING SO LONG AS WILLIAMS FOLLOWS CUSOMTER'S
         BLENDING INSTRUCTIONS, AND ALSO FOLLOWS STANDARD INDUSTRY PRACTICE IN
         ACCOMPLISHING THE BLENDS USING THE FACILITIES AND EQUIPMENT AVAILABLE
         WITHIN THE TERMINAL. CUSTOMER SHALL BE RESPONSIBLE FOR TESTING SUCH
         FINISHED BLENDS AND AUTHORIZING RELEASE FROM THE TERMINAL OF FINISHED
         PRODUCT RESULTING FROM SUCH BLENDS.

III.     NOTICES. Any notice by either party to the other shall be deemed to
         have been properly given if delivered personally, faxed with telephone
         and written confirmation of receipt, or mailed to said party by
         certified or registered mail, postage and charges prepaid, to the
         address set out below, unless and until another address shall have been
         specified in writing by said party.

<TABLE>
<CAPTION>
         <S>                                                     <C>
         Customer:                                               Williams:
         Address:    Williams Energy Marketing and Trading       Address:   Williams Terminal Holdings L.L.C.
                     Attn: Jim Capra                                        Attn: Bill Copeland
                     One Williams Center                                    P.O. Box 3448, MD 720-A
                     Tulsa, OK 74101                                        Tulsa, OK  74101
         Telephone:  713-215-3522                                Telephone: 918-573-3424
                                                                 Facsimile: 918-573-6865
                                                                 Email:     bill.copeland@williams.com
</TABLE>

IN WITNESS WHEREOF the parties have by their duly authorized representatives
signed this Agreement.

Williams Energy Marketing and Trading        WILLIAMS TERMINAL HOLDINGS L.L.C.

      /s/ Mike Selman                              /s/ Bill Copeland
---------------------------------------      ----------------------------------
        (Signature)                                   (Signature)

        Mike Selman                                  Bill Copeland
---------------------------------------      ----------------------------------
       (Print Name)                                  (Print Name)

    V.P. Portfolio Mgt.                           Mgr. - Term. Serv.
---------------------------------------      ----------------------------------
       (Title)                                       (Title)


                  WILLIAMS TERMINALLING AGREEMENT - Page 2 of 2

<PAGE>   3


                          SCHEDULE A - BUSINESS TERMS


1.       Term. This Agreement shall be deemed to have come into force on
September 16, 1999 and shall, subject to any earlier termination under the
provisions of this Agreement or otherwise by law, continue until midnight, CST
or CDT as the case may be, on September 30, 2004 ("Initial Term"). Thereafter,
this Agreement shall be extended from month to month until cancelled by either
party giving to the other party sixty (60) days written notice prior to the end
of the Initial Term or thirty (30) days written notice prior to the end of any
monthly period thereafter.

2.       Compensation: Customer shall, in accordance with this Agreement, pay
the charges set out below throughout the term of this Agreement, and during any
other period in which the Product or any part thereof remains in the Terminal.

OPTION #1

         STORAGE: $.24 per barrel per month. There shall be no carry forward or
         carry back of barrels from one monthly period to another. Storage is
         calculated per tank on the shell capacity for such tank specified
         herein.

         EXCESS TANK TURNS: $.12 per barrel per month (and pro rata for any part
         thereof) for volumes received by the Terminal in excess of the Quantity
         specified in Section 1 of these Business Terms.

         EMISSIONS CONTROL: $0.05 per barrel of Product outbound to marine
         vessel for actual utilization of Williams' emission control unit.

         TANK CIRCULATION: $0.02 per barrel per day.

         TANK-TO-TANK TRANSFER: $0.01 per barrel transferred.

OPTION #2

         STORAGE: $.255 per barrel per month. There shall be no carry forward or
         carry back of barrels from one monthly period to another. Storage is
         calculated per tank on the shell capacity for such tank specified
         herein.

         EXCESS TANK TURNS: $.08 per barrel per month (and pro rata for any part
         thereof) for volumes received by the Terminal in excess of the Quantity
         specified in Section 1 of these Business Terms.

         EMISSIONS CONTROL: $0.05 per barrel of Product outbound to marine
         vessel for actual utilization of Williams' emission control unit.

         TANK CIRCULATION: No charge

         TANK-TO-TANK TRANSFER: No charge


           WILLIAMS TERMINALLING AGREEMENT - Schedule A - Page 1 of 2

<PAGE>   4


3.       Tankage: Williams shall provide Customer with up to Two Million Five
Hundred Twenty One Thousand (2,521,000) barrels of shell capacity tankage space
for the Product (the "Quantity"). The term "barrel" as used herein shall mean 42
U.S. gallons at 60 degrees Fahrenheit. The following tanks allocated to Customer
("Customer's Tankage"). Williams shall notify Customer in writing and shall
receive Customer's written approval prior to changing the specified tank(s)
utilized for storage of Customer's Product.

<TABLE>
<CAPTION>
           TANK NUMBER                  CAPACITY                  OPTION
           -----------                  --------                  ------
           <S>                          <C>                       <C>
           250                             10,000                 1
           251                             10,000                 1
           252                             10,000                 1
           253                             10,000                 1
           254                             10,000                 1
           255                             10,000                 1
           324                            150,000                 2
           367                            323,000                 1
           368                            323,000                 1
           372                            630,000                 1 * , #
           373                            315,000                 1 (1/2 of a fungible tank)
           386                            160,000                 2
           389                            160,000                 2
           390                            120,000                 2
           308                            120,000                 2
           370                            160,000                 2
                                        ---------

                                        2,521,000
</TABLE>


* Tank 372 will change to option #2 effective 2/1/2000.

# Tank 372 will change back to option #1 effective 11/1/2000.

ACKNOWLEDGED AND AGREED TO this       day of                   ,      .
                                -----        ------------------  -----

Williams Energy Marketing and Trading        WILLIAMS TERMINAL HOLDINGS L.L.C.

     /s/ Mike Selman                              /s/ Bill Copeland
---------------------------------------      ----------------------------------
        (Signature)                                   (Signature)

         Mike Selman                                  Bill Copeland
---------------------------------------      ----------------------------------
       (Print Name)                                  (Print Name)

    V.P. Portfolio Mgt.                           Mgr. - Term. Serv.
---------------------------------------      ----------------------------------
       (Title)                                       (Title)



                              - End of Schedule A -

WILLIAMS TERMINALLING AGREEMENT - Schedule A - Page 2 of 2

<PAGE>   5


                SCHEDULE B - PRODUCT TERMINALLING GENERAL TERMS

1.       Terminal Operations. Control and operation of the Terminal shall rest
exclusively with Williams, which shall comply with and provide all
certifications required by all federal, state and local laws, rules and
regulations applicable to the ownership, control and operation of the Terminal.
Customer acknowledges that it is generally familiar with the layout and
capabilities of the Terminal, including tanks, pipelines, equipment, dock and
other facilities comprising it.

2.       Deliveries To and From the Terminal. All deliveries hereunder to
Williams or to Customer shall be at the Terminal by the delivery means set forth
in the Business Terms to which this Schedule A is attached. Marine deliveries to
or from the Terminal permitted in this Agreement shall be made in accordance
with Schedule B. Permitted deliveries into and out of tank trucks and rail cars
shall be made within the Terminal's usual business hours and in accordance with
the Terminal's Operating procedures, as established from time to time by
Williams. If pipeline deliveries are permitted hereunder, Customer shall notify
Williams of any proposed pipeline deliveries into or out of the Terminal as soon
as reasonably possible after Customer receives its schedule from the pipeline
company, refinery, or other such entity. Such notice shall set forth the
quantity, quality and specifications of Product to be delivered by pipeline and
the desired date of delivery to or from the Terminal. Williams shall notify
Customer within two (2) working days of each notice of proposed pipeline
delivery either that it shall accommodate such delivery or that the proposed
delivery conflicts with a previously scheduled pipeline movement or use of
available Terminal tankage by Williams or another party. In the case of such
conflict, Williams shall advise Customer of the next open dates that the
Terminal can accommodate pipeline deliveries in the amounts desired. Williams
shall use reasonable efforts to accommodate Customer's proposed pipeline
deliveries, taking into account the needs of Customer, Williams and other
parties terminalling products at the Terminal. Customer shall immediately notify
Williams upon learning that it shall not be able to receive previously scheduled
Product from or deliver previously scheduled Product to the Terminal, and the
parties shall thereafter cooperate to reschedule such receipt or delivery.
Customer shall reimburse Williams for the cost of any pipeline charges assessed
to Williams for any of Customer's pipeline shipments in or out of the Terminal,
and for any charges assessed to Williams by the operator of any vessel
transporting Product in or out of the Terminal. IF, FOR ANY REASON OTHER THAN
WILLIAMS' OR ITS EMPLOYEES' SOLE NEGLIGENCE OR WILLFUL ACT OR OMISSION, WILLIAMS
INCURS ANY COST, LOSS OR DAMAGE AS A RESULT OF ANY RECEIPT OR DELIVERY BEING
CANCELED, RESCHEDULED, OR FAILING TO MEET SCHEDULE OR THE TERMS OF THIS
AGREEMENT, OR ANY PRODUCT REMAINING IN THE TERMINAL AFTER THE EXPIRATION OR
OTHER TERMINATION OF THIS AGREEMENT, CUSTOMER SHALL INDEMNIFY WILLIAMS FOR SUCH
COSTS, LOSSES, AND DAMAGES IMMEDIATELY UPON PRESENTATION OF INVOICE. CUSTOMER'S
LIABILITY FOR SUCH COSTS, LOSSES, AND DAMAGES PURSUANT TO THIS SECTION IS IN
ADDITION TO ANY HOLDOVER FEES SPECIFIED IN ANY OTHER PART OF THIS AGREEMENT.

3.       Measurement and Testing. Subject to the delivery means specified in the
Business Terms, quantities delivered into or from marine vessels, pipelines,
trucks, or rail cars shall be measured

          WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 1 of 10

<PAGE>   6


by Terminal tank gauges. The term "marine vessel(s)" as used herein shall mean
any type of ship, barge, tug, or other waterborne craft. The term "gallons" as
used herein shall mean a US gallon of 231 cubic inches temperature corrected to
60 degrees Fahrenheit in accordance with the appropriate ASTM standard. Tests
for quality shall be made in accordance with established ASTM standards and
methods, except to the extent such standards and methods conflict with
applicable governmental standards and methods. In the event of such conflict,
governmental standards and methods shall control. A mutually acceptable
independent inspector may be appointed to test and measure Product deliveries to
and from the Terminal. The cost of said inspector, including laboratory and
other inspection costs, shall be borne by Customer. In the absence of any tests
or measurements by an independent inspector, the results of the tests and
measurements made by Williams on the Product shall be conclusive and binding on
Customer, except in the event of fraud or manifest error. Customer shall have
the right, at any time during normal business hours, periodically to inspect the
Terminal in order to make physical checks of Customer's Product in Williams'
custody, and to generally observe Williams' performance of operations hereunder.
However, this right shall not be exercised in such a manner as to interfere with
or diminish Williams' control over the operation of the Terminal. Williams'
obligation hereunder to redeliver terminalled Product to Customer shall be
completely satisfied by redelivering the volume of such Product initially
delivered by Customer to Terminal less transmix, and less the loss allowance set
forth in this Agreement. Tank heel volume shall be put in place by Customer upon
initial delivery and be made available to Customer within thirty (30) days of
termination of this Agreement. Tankage allotments may change from time to time,
and Williams reserves the right to adjust Customer's tank heel contribution as
Terminal operations dictate. As an alternative to the tank heels being
physically returned to Customer, at Customer's request and direction, Williams
shall try to arrange for the sale, transfer, or exchange to third parties of the
tank heels. Should these alternative means be unsuccessful, Customer shall then
physically take delivery of the tank heels.

4.       Quality. Customer warrants that the Product delivered by it hereunder
shall comply with applicable federal, state and local laws, rules and
regulations, including, but not limited to, those governing Reid Vapor Pressure,
sulfur content and octane levels for finished gasoline. If any Product tendered
for delivery to the Terminal by Customer fails to meet such applicable laws,
rules and regulations, Williams may, at Williams's sole election and in addition
to any other rights and remedies Williams may have at law or in equity, (a)
reject the Product and refuse to take delivery; (b) take delivery of the Product
and store it, at Customer's cost, until such time as Customer can remove the
Product from the Terminal; or (c) take delivery of the Product and, at
Customer's cost, blend or otherwise conform it to such applicable laws, rules
and regulations. Williams reserves the right, at Williams's election, to refuse
to deliver out of the Terminal as finished Product any of Customer's Product
which fails to meet applicable federal, state and local laws, rules and
regulations including, without limitation, Reid Vapor Pressure, sulfur content,
octane levels or any other specifications for finished Product. SHOULD WILLIAMS,
AT CUSTOMER'S REQUEST, DELIVER OUT OF THE TERMINAL AS FINISHED PRODUCT ANY
PRODUCT WHICH FAILS TO MEET ANY SUCH APPLICABLE STANDARD, CUSTOMER HEREBY AGREES
TO ACCEPT SOLE RESPONSIBILITY FOR SAID PRODUCT AND DEFEND, INDEMNIFY AND HOLD
WILLIAMS HARMLESS AGAINST ANY LIABILITY DIRECTLY RESULTING FROM SAID DELIVERY.

          WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 2 of 10

<PAGE>   7


5.       Product Responsibility. Title to Product shall not pass to Williams.
Williams shall not be responsible for chemical deterioration or oxidation of
products resulting from stagnant storage of Product, and in no event shall
Williams be liable as an insurer of product. Williams shall not be liable for
any damage or loss to Customer's Product (including without limitation damage or
loss caused by fire, leakage, contamination or other similar cause), except to
the extent that such damage or loss results from the sole negligence or willful
act or omission of Williams or its employees. In receiving from marine vessels,
trucks, rail cars, or pipelines, Customer shall be responsible for product until
it enters Williams's fixed dock flange, pipeline receiving flange, or receiving
hose, as the case may be. In delivering to marine vessels, trucks, rail cars, or
pipelines, Customer shall be responsible for Product when it leaves Williams's
fixed dock flange, pipeline delivery flange, or delivery hose, as the case may
be. Notwithstanding any other provisions of this Agreement regarding losses, the
parties agree that Williams, if otherwise liable pursuant to this agreement with
respect to any lost or damaged product, shall in no event be liable for more
than the lesser of either (a) the actual cost of product to Customer, or (b) the
market value at the time of loss, less salvage value. If any of Customer's
product is sold, exchanged, or otherwise not owned by Customer while in storage
at the terminal, Customer shall nonetheless be deemed the owner thereof for
purposes of this Agreement. Customer shall continue to be responsible for,
without limitation, all charges, taxes, terms and conditions of this agreement
as if such product were owned by Customer. Williams and Customer agree that,
unless specifically set forth otherwise in this Agreement, any demurrage on
marine vessels, rail cars or trucks is for the account of Customer.

6.       Product Information. Customer shall sign in its name, pay for and
furnish to Williams at the Terminal all information, documents, labels,
placards, containers and other materials and data which may be required or
requested by any governmental or regulatory authority or by statutes,
ordinances, rules or regulations of any governmental or regulatory authority
(the "Regulations") relating to the describing, packaging, receiving, storing,
handling, blending, shipping or disposing of any Product or related materials,
to or from the Terminal, together with detailed written instructions as to their
use and disposition, except to the extent Williams as a terminal operator is
obligated by applicable laws to provide such information. Williams may report to
any governmental or regulatory body information in regard to the Product,
related materials and activities of Customer, and Customer shall provide such
information relating to this Agreement to Williams as may be necessary, in
Williams's reasonable opinion, to comply with the foregoing. Further, the
parties acknowledge that Williams may have an obligation to furnish certain
information to governmental authorities or others handling or exposed to the
Product, or to the general public. Customer shall furnish to Williams current
and accurate material safety data sheets for all of Customer's Product prior to
that Product entering the Terminal so that Williams may comply with such
obligations. Customer shall have the responsibility for filing and pursuing any
exemption from disclosure pursuant to such laws and regulations which Customer
may desire. Customer shall prepare, file and maintain copies of all reports
required of it to be filed with any federal, state or local governmental agency
concerning the receipt, delivery and storage of its Product, except to the
extent Williams as a terminal operator is obligated by applicable laws and
regulations to provide such information. Copies of all such reports shall be
promptly transmitted to Williams upon request.

7.       Removal of Product. During this Agreement, Customer shall retain
sufficient Product in the Terminal, in Williams's reasonable opinion, to
maintain minimum levels in the storage tanks

          WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 3 of 10

<PAGE>   8


and pipelines, taking into account the needs of pump suction and any floating
roof tanks, if such are being utilized. Customer agrees to remove promptly, upon
the expiration or other termination of this Agreement, or at such other time as
may be required by governmental or regulatory mandate during the term hereof,
all Product and any materials or residue relating thereto from the Terminal
unless Williams has asserted a lien on the Product as provided below. Should any
Product remain in the Terminal beyond the expiration or other termination of
this Agreement, Customer shall remain obligated to comply with the terms of this
Agreement, and shall also be obligated to pay an additional holdover charge per
tank containing any such Product based on the following formula: capacity of
tank times $ 0.02 per barrel per day, until all the Product and related
materials are removed. Should Williams incur any charges, damages or liability
to other parties as a direct result of Customer's failure to remove the Product
and related materials as provided above, Customer shall be responsible for all
such charges, damages or liability. During and after the term hereof, Customer
shall be completely responsible for the removal from the Terminal and disposal
of all waste relating to Product. If Customer wishes Williams to implement the
removal and disposal of Customer's waste and Williams so agrees, Customer must
give Williams specific, lawful directions for that activity. Customer shall pay
all costs associated with such removal and disposal, including any taxes or
other governmental charges Williams may incur in connection with it.

8.       Services by Williams. Williams may refuse to perform any services
contemplated hereunder if such performance would, in Williams's reasonable
judgment, be unsafe under the circumstances or cause unusual or excessive wear
and tear or potential damage to the Terminal or any part of it. In addition to
other compensation payable hereunder, Customer shall pay Williams the costs of
providing extra or special services. Such special services shall include without
limitation (a) any additional service or function requested by Customer and
agreed to by Williams including, without limitation, any removal and/or disposal
of Product or waste by Williams and tank cleaning as set forth in Sections 7 and
16 of this Schedule A; (b) any necessary service or function not specifically
provided for in this Agreement, including such items as fuel and electricity
costs incurred to heat Customer's commodities; and (c) any double-time, call-in
time, salaried time, overtime and similar costs necessitated by changes in
vessel schedules or arrivals for which proper vessel nomination and estimated
time of arrival has not been given as provided in Schedule B. For these
services, Customer shall pay Williams the sum of the cost to Williams of
services contracted to enable Williams to carry out such service or function, if
any, plus fifteen per cent (15%).

9.       Invoicing and Payment. Williams shall invoice Customer each month for
the previous month's charges as set out in the Business Terms, as well as other
sums owing pursuant to this Agreement for prior months. Customer agrees to pay
such charges to Williams via wire transfer, monthly in arrears within thirty
(30) days from the due date of the invoice. Customer also agrees that all other
payments invoiced by Williams hereunder shall be paid via wire transfer within
thirty (30) days from the due date of the invoice. All payments shall be made by
Customer in strict accordance with this Agreement and without deduction, setoff
or counterclaim; any dispute as to the amount of any invoice shall be resolved
after payment of the disputed invoice by Customer. Time is of the essence with
respect to all obligations under this Agreement. The amount of any invoice, if
not paid within thirty (30) days from the due date of the invoice from Williams,
shall bear interest at the rate of one and a half per cent (1.5%) per month (or
the highest rate permitted by law, whichever is less) for each month or portion
of a month thereafter

           WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 4 of 10

<PAGE>   9


during which such amount remains unpaid. All payments shall be made to Williams
in accordance with reasonable payment instructions set forth in invoices from
time to time. Customer shall identify by number the invoices being paid in the
wire transfer comments. All charges under this Agreement shall be subject to
escalation of one and on-half percent (1 1/2%) each year of this Agreement. Such
escalation shall commence January 1st of the year following the first annual
anniversary date of this Agreement. Acceptance by Williams of any payment from
Customer for any charge or service either after the termination or expiration of
this Agreement or otherwise shall not be deemed a renewal of this Agreement or a
waiver by Williams, and all of Customer's payment and indemnity obligations
hereunder shall survive the expiration or termination of this Agreement.
Williams agrees to maintain books and records relating to tank storage, services
and facilities under this Agreement in connection with any payment made under
this Agreement for a period of two (2) years after delivery of service
hereunder. In the event Customer requests an audit, such request shall be in
writing and such audit shall be at Customer's expense; Williams shall permit
Customer access during normal working hours to Williams' property and records
relating to Customer's transactions under this Agreement as is necessary to
effectuate such audit.

10.      LIABILITIES. WILLIAMS SHALL INDEMNIFY AND HOLD CUSTOMER HARMLESS FROM
AND AGAINST ALL CLAIMS, DAMAGES, FINES, PENALTIES, LOSSES, SUITS, LIABILITY AND
EXPENSES (INCLUDING, WITHOUT LIMITATION, THOSE WHICH ARE ENVIRONMENTALLY
RELATED) CAUSED BY OR RESULTING FROM THE GROSS NEGLIGENCE OR WILLFUL ACTS OR
OMISSIONS ON THE PART OF WILLIAMS, ITS EMPLOYEES, AGENTS, OR CONTRACTORS IN THE
PERFORMANCE OF THIS AGREEMENT. CUSTOMER SHALL INDEMNIFY, DEFEND AND HOLD
WILLIAMS, ITS AFFILIATES, AND THEIR EMPLOYEES, OFFICERS, AND DIRECTORS HARMLESS
FROM AND AGAINST ALL CLAIMS, DAMAGES, FINES, PENALTIES, LOSSES, SUITS, LIABILITY
AND EXPENSES (INCLUDING, WITHOUT LIMITATION, THOSE WHICH ARE ENVIRONMENTALLY
RELATED) CAUSED BY OR RESULTING FROM (A) THE ACTS OR OMISSIONS ON THE PART OF
CUSTOMER, ITS EMPLOYEES, AGENTS OR CONTRACTORS (INCLUDING, BUT NOT LIMITED TO,
THE ACTS OR OMISSIONS OF ANY OWNER, OPERATOR, OR VOYAGE CHARTERER OF ANY MARINE
VESSEL CHARTERED, CONTRACTED OR NOMINATED BY CUSTOMER IN RELATION TO THIS
AGREEMENT), AND (B) LIABILITY ARISING FROM THE CHEMICAL CHARACTERISTICS OF
COMMODITY. ANY INDEMNIFICATION GRANTED HEREUNDER BY ONE PARTY TO THE OTHER PARTY
SHALL SURVIVE THE TERMINATION OF ALL OR ANY PART OF THIS AGREEMENT. Customer
shall cause all marine vessels, truck carriers and rail car carriers which are
chartered, contracted, or nominated hereunder by Customer to comply with all
applicable federal, state and international laws and regulations, and to carry
all necessary liability and pollution insurance required by law. Customer shall
cause its agents, invitees, contractors, subcontractors, representatives, and
employees, including, but not limited to, carriers contracted or employed by
Customer to transport product by trucks, rail cars, or marine vessels, to sign
the Terminal Use and Access Agreement ( the "Access Agreement") in the form of
schedule d attached hereto and incorporated herein. Customer shall assist
Williams in obtaining execution of the access agreements. Williams may, at
Williams' sole discretion, deny access to the terminal or terminal wharf to
agent, invitee, contractor, subcontractor, representative, or employee who fails
to execute such Access Agreement. NOTWITHSTANDING THE FOREGOING, UNDER NO

           WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 5 of 10

<PAGE>   10


CIRCUMSTANCES SHALL WILLIAMS HAVE ANY LIABILITY TO CUSTOMER FOR LOSS OR DAMAGE
RESULTING FROM A DELAY IN THE HANDLING OF THE PRODUCT UNDER THIS AGREEMENT OR
ANY OTHER INCIDENTAL, CONSEQUENTIAL, SPECIAL OR INDIRECT LOSS, DAMAGE OR COST
(INCLUDING, BUT NOT LIMITED TO, ANY LOSS OF BUSINESS OPPORTUNITY, LOSS OF
PRODUCTION, LOSS OF PROFITS OR LOSS OF USE), HOWSOEVER AND BY WHOMSOEVER CAUSED,
EVEN IF THE POSSIBILITY OF SUCH LOSS, DAMAGE OR COST WAS FORESEEABLE.

11.      Taxes and Other Charges. Customer shall pay that portion of all taxes,
charges, costs, fees and assessments of whatever nature (including without
limitation wharfage, dockage or other similar charges) which represent increases
above those paid by Williams prior to the effective date of this Agreement and
which may be assessed by any governmental or regulatory authority against (or
which may be imposed by or result from any law, regulation or governmental
authority upon) any Product, the property of Customer, or Williams (except for
income or customary property taxes) in relation to the Terminal or its
infrastructure, or the receiving, storing, handling, shipping or disposing of
Customer's Product, waste or property. Upon written request by Williams,
Customer agrees to supply Williams with a complete signed original Notification
Certificate of Gasoline and Diesel Fuel Registrant as required by the Internal
Revenue Service's excise tax regulations. In the event the costs contemplated by
this section are reasonably allocable to all customers of the Terminal, Customer
shall pay its pro rata share thereof based upon the percentage of usable tankage
space utilized. If any governmental or regulatory body imposes new requirements
after the effective date of this Agreement which require Williams, or should any
change in law or regulation since such date require Williams, to incur any
additional expense or effect any investment to comply with any laws or
governmental regulations, Customer may elect to pay its direct or pro rata share
as described above, as appropriate, of the expenses or investment, including
engineering and construction management expenses and subsequent direct costs, as
may be escalated, of operating and maintaining such changes or additions. If
Customer elects not to pay such direct or pro rata share as described above,
then Williams shall have the option to terminate this Agreement with sixty (60)
days prior written notice. Williams is attempting to obtain the status of
foreign-trade zone operating within the Houston-Galveston Customs Port of Entry
for the Galena Park terminal. 19 CFR Section 101.3 designates the
Houston-Galveston Customs Port of Entry as "the territory lying within the
corporate limits of both Houston and Galveston, and the remaining territory in
Harris and Galveston Counties." In accordance with 19 USC 8 1 (o)(e), companies
holding title to inventory held within the zone are entitled to exemption from
state and local ad valorem taxation of tangible personal property. However, in
the event that Williams obtains foreign-trade zone status for the Galena Park
terminal, it will enter into an agreement with local taxing jurisdictions to
waive this exemption and thus its customers will not be entitled to this tax
exemption. Therefore, all state and local ad valorem taxes on tangible personal
property shall, at all times, be paid by Customer.

12.      Force Majeure. Notwithstanding any other provision of this Agreement,
if Williams fails or is unable, in whole or in part, to perform any obligation
required of it hereunder, and such failure or inability is caused by acts of
God, accidents, storms, hurricanes, floods, extreme heat or cold, electrical
shortage, fires, acts of enemies or terrorists, explosions, strikes, lockouts,
labor troubles, compliance with any governmental law, rule or regulation,
inability to obtain or renew

           WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 6 of 10

<PAGE>   11


any governmental authorizations, consents or permits, inability to procure
materials or equipment or supplies, breakdowns or breakages, tank or dock or
other outages for maintenance or repair, failure of power, or any other cause
similar or dissimilar to the foregoing which is beyond its reasonable control,
such failure or inability shall not be deemed to be a violation of this
Agreement. Furthermore, without incurring any liability to Customer, Williams
shall have the right to shut down the Terminal or any part thereof in the event
any personnel, equipment, structure or the environment are, in Williams's
reasonable opinion, either in danger or at risk of injury or damage. If, while
this Agreement is in effect, Williams's use of all or part of the Terminal for
the storage and handling of any Products shall be restrained or enjoined by
judicial process, restricted or terminated by any governmental or regulatory
authority or by right of eminent domain or by the owner of leased land,
Williams, upon being notified of such restraint, enjoinder, restriction or
termination, shall notify Customer, and Williams may suspend or terminate
affected terminalling services hereunder. In the event that all or part of the
Terminal or the facilities normally utilized by Customer are destroyed, Williams
shall, in its sole discretion and as soon as reasonably possible thereafter and
in any event within six (6) months, either elect to commence repair of the
Terminal, in which event this Agreement shall remain in full force and effect,
or elect to not repair the Terminal, in which event Williams shall suspend or
terminate affected terminalling services hereunder. Upon any such total or
partial termination hereunder, Customer shall be obligated to pay all accrued
charges, and Williams shall have no liability to Customer for such termination.
In the event that, due to any of the circumstances described in this Section 12,
the terminalling storage or space is restricted or unavailable for use by
Customer, Williams shall adjust the charges payable under this Agreement
proportionately to obligate Customer for payment for terminalling storage or
space actually available to Customer.

13.      Default and Claims. Either party shall be in default hereunder if (a it
fails to pay any sums payable hereunder as and when due, or, subject to Section
12. otherwise fails to strictly perform and observe any material term or
condition of this Agreement; or (b) a custodian, receiver, liquidator, or
trustee of such party is appointed or takes possession of it or some or all of
its business, or such party generally fails to pay its debts as they become due
or makes an assignment for the benefit of its creditors, or is adjudicated
bankrupt or insolvent, or an order for relief is entered under the Federal
Bankruptcy Code against it, or any of its property is sequestered by court
order, or a petition is filed by or against it under any bankruptcy,
reorganization, arrangement, insolvency, readjustment of debt, dissolution or
liquidation law of any jurisdiction, whether now or subsequently in effect. In
the event of any such default, the other party shall, without prejudice to its
rights hereunder and in addition to such other rights and remedies as may be
available, have the right to immediately terminate this Agreement. In the event
that Customer is in default hereunder, Williams shall have a lien upon and have
the right to retain possession of any Product of Customer in any of Williams'
Terminal facilities for any monies owing to Williams hereunder which have not
been paid when due (whether incident to the Product then in the Terminal or
otherwise) but only to that extent and no further. Customer shall immediately
give notice to Williams in writing of any claim or dispute hereunder, and
include as part of such notice full and complete details, specifics and backup
documentation pertaining to it. In no event shall Williams be liable to Customer
unless such a written notice together with all supporting documentation
available is delivered to Williams by Customer within sixty (60) days after the
facts upon which the claim or dispute is based first became known, or reasonably
should have first become known, to Customer.

           WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 7 of 10

<PAGE>   12


14.      Commissions and Gifts. No director, officer, employee, agent or
subcontractor of either party shall give or receive any commission, fee, rebate,
gift or entertainment of significant value or cost in connection with this
Agreement. Further, neither party shall give any commission, fee, rebate, gift
or entertainment of significant value or cost to any government official or
employee in connection with this Agreement.

15.      Confidentiality. The parties understand and agree that the terms and
conditions of this Agreement, all documents referred to herein and
communications between the parties regarding this Agreement (collectively
"Confidential Information") are confidential as between Williams and Customer
and shall not, without the other party's prior written consent, be disclosed by
a party to a third party, other than an affiliate who has a need to know. In the
event that either party is requested or becomes legally compelled (by oral
questions, interrogatories, request for information or documents, subpoena,
civil investigative demand or similar process) to disclose any Confidential
Information, it shall give the other party prompt notice thereof so that a
protective order or other appropriate remedy may be sought and/or waiver of
compliance with the provisions of this Agreement granted. The party requesting a
protective order shall bear all costs related thereto. In the event that such
protective order or other remedy is not obtained, the party who has been
requested or legally compelled to disclose Confidential Information agrees that
it shall furnish only that portion of the Confidential Information which is
legally required and shall exercise its reasonable efforts to obtain reliable
assurance that confidential treatment shall be accorded to the Confidential
Information which is disclosed in such manner.

16.      Tank condition, wastes and cleaning. Customer acknowledges that tankage
was originally received by Customer in clean condition, suitable for the storage
of Product and agrees to return tankage in the same clean condition as
originally received, normal wear and tear excepted. If Williams determines in
its reasonable discretion that it is necessary to clean tankage upon termination
of this Agreement or, due to a change in the nature of the Product stored or to
be stored therein, during the term hereof, or both, or if Customer desires to
change the type of Product to be stored (in which case, Customer shall give
Williams reasonable prior written notice thereof), Customer shall be responsible
for all reasonable tank cleaning charges, and for the removal from the tankage
and subsequent lawful disposal of Customer's waste in accordance with the
provisions of Section 7 of Schedule A hereto. For the purposes of this Agreement
"waste" shall mean any tank bottom or tank heel, water, sludge, sediment,
particulate or other residual material remaining in tankage resulting from the
storage and handling of Product.

17.      Insurance. The rates quoted herein do not include any insurance on the
Product covered hereunder while it is the possession of Williams, it being
clearly understood and agreed that cargo insurance, if any be desired by
Customer, shall be carried by Customer at its own expense. If Customer does
carry cargo insurance, Customer's cargo insurance underwriters shall waive all
rights of subrogation against Williams and Customer shall provide Williams with
evidence of such waiver of subrogation. Both parties shall obtain and maintain
in full force and effect commercial general liability coverage which shall
include, but not be limited to, bodily injury, property damage, contractual
liability and contractor liability with limits of at least $2MM per occurrence
and with insurance companies reasonably satisfactory to the other party as
respects all duties and obligations pursuant to this Agreement. Each party shall
also maintain in full force and effect Workers' Compensation insurance complying
with the laws of the state or states having jurisdiction over each employee and
Employer's Liability coverage with limits of at least

           WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 8 of 10

<PAGE>   13


$1MM each accident, $1MM disease each employee and $1MM disease policy limit.
For any work performed offshore or on navigable waterways, this insurance shall
be endorsed to provide full Maritime liability coverage, including
Longshoreman's and Harbor Worker's Act, Outer Continental Shelf Land Act, Jones
Act, Death on High Seas Act and In Rem. Both the commercial general liability
and workers' compensation policies carried by each Party shall waive subrogation
rights in favor of the other Party to the extent of the indemnity obligations
specified in Sections 2, 3, 4, and 10 of this Schedule A and Section III of the
Business Terms. Each party shall provide to the other party certificates showing
evidence of such coverages as of the effective date of this Agreement. Each
party shall maintain all such policies current. The mere purchase and existence
of insurance does not reduce or release either party from any liability incurred
and/or assumed within the scope of this Agreement.

18.      Allowances. Williams shall be allowed, for actual losses incurred, up
to a maximum of 0.5% loss/handling allowance on the quantity of Product
delivered by Customer during the term of this agreement. Customer agrees that
Williams shall not be liable for such loss.

19.      GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY THE LAWS OF THE
STATE OF OKLAHOMA WITHOUT REGARD TO CHOICE OF LAW PRINCIPLES.

20.      Assignment. Customer shall not assign or transfer this Agreement in
whole or in part, or any of the rights or obligations contained herein
(including, but not limited to, the right to the storage of Product), without
the prior written consent of Williams. Such consent to assignment or transfer by
Customer shall not relieve Customer from any of its duties or obligations under
this Agreement, unless otherwise specifically stated in the written consent to
that assignment or transfer. This Agreement shall not be assigned in whole or in
part by Williams except with the prior written consent of Customer; provided,
however, Williams may assign this Agreement an affiliate without such consent.
"Affiliate" means any entity which directly or indirectly controls, is
controlled by, or is under a common control with Williams. The term "control"
(including the terms "controlled by" and "under common control with") as used in
the preceding sentence means the possession, directly or indirectly, of the
power to direct or cause the direction of management and policies of an entity.
Subject to the foregoing, this Agreement shall bind and inure to the benefit of
the successors, assigns and transferees of the parties hereof.

21.      Concluding Provisions. This Agreement is made as an accommodation to
Customer, and in no event shall Williams' services hereunder be deemed to be
those of a public utility or common carrier. If any action is taken or
threatened by any governmental or other authority to declare the Terminal,
Williams or Customer a public utility or common carrier, Williams may by written
notice terminate this Agreement on the effective date of such action. Williams
shall own all improvements to the Terminal, including those for which Customer
has made a financial contribution. Customer shall, at its reasonable discretion,
sign any and all further documents and instruments, and take any and all
actions, reasonably necessary or advisable to carry out the intent, purpose
and/or provisions of this Agreement, or to meet reasonable financing
requirements of banks or others making loans in relation to the Terminal.
References in this Agreement to "days," "months" or "years" shall mean to
calendar days, months and years unless otherwise indicated. If any provision of
this Agreement is held to be unenforceable to any extent, the remaining
provisions shall be enforced to the maximum extent allowed by law. All section

           WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 9 of 10

<PAGE>   14


titles and headings in this Agreement are merely for convenience, and shall not
limit in any way the interpretation of this Agreement. No provisions of this
Agreement shall be construed against or interpreted to the disadvantage of any
party by reason of such party's having drafted such provision. The remedies
provided in this Agreement are cumulative, not exclusive, and in addition to all
other remedies in either party's favor at law, in equity or otherwise. No waiver
of any breach by either party of any terms, conditions, or obligations shall be
deemed a waiver of subsequent breaches of the same or other nature. This
Agreement shall not be deemed to be for the benefit of any third party, or give
any other party any right to enforce its provisions and neither this Agreement
nor the parties' performance hereunder shall be deemed to have created a joint
venture or partnership between the parties. This Agreement constitutes the
entire agreement between the parties. There are no promises, terms, conditions
or obligations other than those contained herein. No variation or modification
hereof shall be deemed valid unless it is in writing and signed by both parties.

                              - End of Schedule B -


          WILLIAMS TERMINALLING AGREEMENT - Schedule B - Page 10 of 10


<PAGE>   15


                   SCHEDULE C - MARINE TERMINALLING PROVISIONS

1.       Marine Vessel Nomination. To nominate a berth at the Terminal wharf,
Customer shall give Williams in writing a Nomination Notice which (a) proposes a
one-to-three (1-3) day date range for loading or discharge of a specific vessel
at the Terminal; (b) specifies the proposed vessel's name, flag, deadweight
tonnage, length, beam and draft, and the volume and nature of cargo Customer
intends to load/discharge; and (c) provides such additional information or
documentation as Williams may reasonably request from time to time. Williams
shall handle Nomination Notices on a first-come-first-served basis. Williams
shall have the right to refuse approval of the proposed Nomination Notice or any
portion thereof, including but not limited to the vessel nominated and/or the
proposed date range; provided, however, that Williams's approval shall not be
unreasonably withheld. Williams's response to a Nomination Notice shall be
communicated to Customer within one business day (0800 to 1700 hours CST or CDT,
as the case may be, Monday through Friday, state and federal holidays excepted).
Williams's approval of any vessel shall not constitute a continuing approval of
that vessel for any subsequent loading or discharge.

2.       Estimated Time of Arrival. that vessel for any subsequent loading or
discharge. Customer or Customer's marine agent shall notify Williams of the
estimated date and time of arrival at the Terminal of each vessel with an
approved Nomination Notice as soon as this information is available, but no
later than five (5) calendar days in advance of said estimated time of arrival.
The vessel shall be required to send Williams answers to preberthing questions
at least 48 hours prior to the actual estimated time of arrival. Williams shall
provide these preberthing questions to the vessel early enough to allow the
vessel a reasonable time to respond.

3.       Notice of Readiness. After the vessel has arrived at the customary
anchorage or other place of waiting, received all required clearances from
governmental authorities and is otherwise in all respects ready to proceed to
berth and commence loading or discharging cargo, the vessel shall tender a
Notice of Readiness to Williams in writing or via other available means
acceptable to Williams. The Notice of Readiness shall document the estimated
time the vessel is able to arrive at the Terminal wharf given all tidal and
other constraints. A Notice of Readiness shall not be considered valid if at the
time the Notice of Readiness is tendered Customer has failed to timely comply
with any financial, insurance and/or financial responsibility conditions (such
as posting a letter of credit) or any other provision of this Agreement.

4.       Vessel Berth. Williams shall designate a berth for the vessel.
Notwithstanding any other provisions in this Agreement, Williams shall not be
deemed to warrant the safety of any channel, anchorage or other waterway used in
approaching or departing from the designated berth, and Williams shall not be
liable for any loss, damage, injury or delay to the vessel resulting from the
vessel's use of such channel, anchorage or waterway. All vessels chartered,
contracted or nominated by Customer shall be dimensionally acceptable and meet
all requirements of the Terminal's wharf facilities and governmental agencies.

5.       Berthing Order. Vessels arriving and issuing valid notices of readiness
within the date range approved by Williams pursuant to Section 1 of these Marine
Terminalling Provisions (the "approved laydays") shall be berthed at the
Terminal dock in the order of their tendering of valid notices of readiness and
shall have priority over early or late vessels. A vessel arriving before its


           WILLIAMS TERMINALLING AGREEMENT - Schedule C - Page 1 of 2

<PAGE>   16


approved laydays shall, at the sole judgment and discretion of Williams, either
be scheduled into the next available time slot on the Terminal dock schedule or
required to wait for its approved laydays. A vessel arriving after its approved
laydays shall be allocated available time slots on the dock schedule. The
foregoing notwithstanding, Williams shall be entitled to make exceptions to the
above set forth berthing priority rules if, in Williams's sole judgment and
discretion, the safe operation of the Terminal requires such action. A vessel
shall be deemed to have arrived at such time as the vessel has given a valid
Notice of Readiness to Williams.

6.       Berth Shifting. Williams shall have the right to require Customer to
shift any vessel chartered, contracted or nominated by Customer hereunder from
one berth to another at the Terminal. Time spent or lost on account of such
shifting shall count as laytime or for demurrage, as the case may be, and
Williams shall bear all costs thereof, except that if shifting is required by
Customer or the vessel master, is for the safety of the vessel or involves
movement from one terminal to another, expenses shall be borne by Customer and
time spent or lost thereby shall not count as laytime or for demurrage. Except
as specifically stated above, all laytime and demurrage costs shall be borne by
Customer.

7.       Vacating Berth. Williams may order any vessel chartered, contracted or
nominated by Customer hereunder to vacate its berth if such action is required,
in Williams's sole judgment and discretion, for the safe operation of the
Terminal. If the vessel is required to so vacate its berth, and the vessel,
after tendering notice of readiness to recommence loading or discharging, shall
be reberthed in the next open time slot on the Terminal dock schedule.

8.       Pollution. Prevention and Responsibility. Customer shall insofar as it
is able under the terms of any applicable charterparty agreement require that
vessels chartered, contracted or nominated by Customer promptly and diligently
prevent, mitigate and remediate all pollution emanating from said vessels. All
vessels chartered, contracted or nominated by Customer hereunder shall be
participating vessels in the International Tankers Owners Pollution Federation
(ITOPF), or in the case of tows and/or barges, its equivalent, and shall have
secured and carry a current U.S. Coast Guard Certificate of Financial
Responsibility (Water Pollution). Williams shall not be responsible for
demurrage or other expenses resulting from the failure of a vessel to meet the
requirements of this section.

9.       Marine Vapor Recovery and Emissions Reduction. All vessels and barges
chartered, contracted or nominated by Customer hereunder shall comply with
emissions limits established by the Terminal from time to time, and shall
perform, provide, possess and utilize all tests, test results, equipment and
other things necessary in Williams's reasonable opinion to (a) meet all
applicable governmental and Terminal laws, rules and regulations, as modified
from time to time pertaining to marine vapor recovery and emissions reduction;
and (b) properly utilize Williams's vapor recovery unit and emission reduction
systems. All vessels shall have vapor recovery manifolding, connections and
controls compatible with the Terminal's vapor recovery equipment and designed
and operated to ensure that all vapors evolved or displaced by loading and
off-loading operations are safely contained.

                              - End of Schedule C -


           WILLIAMS TERMINALLING AGREEMENT - Schedule C - Page 2 of 2