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                                                                   EXHIBIT 10.11


                          PURCHASE AND SALE AGREEMENT
                         AND JOINT ESCROW INSTRUCTIONS

         THIS PURCHASE AND SALE AGREEMENT AND JOINT ESCROW INSTRUCTIONS
("Agreement") is made this 1st day of February, 2001 by and between CALMAT CO.,
a Delaware corporation (" Seller") and HUNTWAY REFINING COMPANY, a Delaware
corporation ("Buyer").

                                    RECITALS

         A. Seller is the owner of approximately four (4) acres of land commonly
known as 1601 N. Alameda Street, in the City of Los Angeles, County of Los
Angeles, State of California, as described on Exhibit "A" attached hereto and
incorporated herein (the "Land") (APN 7426-028-004). Buyer currently leases a
portion of the Land (the "Refinery Land") from Seller pursuant to that certain
Amended and Restated Ground Lease dated July 31, 1987 between Industrial
Asphalt, as landlord, and Huntway Refining Company, a California limited
partnership, as tenant (the "Refinery Lease").

         B. Seller desires to sell and Buyer desires to purchase all of Seller's
interest in the "Property" (as defined below), for the consideration and on the
terms and conditions hereinafter set forth.

                                    AGREEMENT

         1. PURCHASE AND SALE. Seller agrees to sell, convey and deliver to
Buyer and Buyer agrees to purchase and accept from Seller, Seller's interest in
the Property, on the terms and conditions contained hereinafter. As used herein,
the term "Property" includes Seller's interest in the Land and the Refinery
Lease, and, to the extent transferable or assignable, Seller's interest as
lessee under the "Railroad Leases" (defined below).

            1.1 Seller, as successor to Industrial Asphalt, is the lessee under
(i) that certain Commercial Lease No. 194292 (the "Commercial Lease") dated
April 14, 1981 between Southern Pacific Transportation Company ("SPT"), as
lessor, and Huntmix, Inc. ("Huntmix"), as lessee; and (ii) that certain
Industrial Lease No. 194293 (the "Industrial Lease") dated April 14, 1981
between SPT as lessor and Huntmix as lessee. The Commercial Lease and the
Industrial Lease are together referred to as the "Railroad Leases." Pursuant to
that certain Subtenancy Agreement dated April 14, 1981, Huntmix subleased its
interest in the Commercial Lease to Huntway Partners L.P. Pursuant to certain
Assignments effective as of December 20, 1983, Huntmix assigned its interest(s)
as lessee under the Railroad Leases to Industrial Asphalt.

            1.2 Buyer acknowledges that a portion of the Land is the subject of
condemnation proceedings by the Alameda Corridor Transportation Authority (the
"ACTA


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Condemnation"). The completion of the ACTA Condemnation is a condition precedent
to the Closing hereunder, subject to Seller's right to waive such condition as
described in Section 3.2 below. Upon the completion of the ACTA Condemnation,
the description of the Land will be revised to reflect the area taken in
connection with the ACTA Condemnation. Buyer understands that the Property does
not include, and Seller hereby reserves all right, title and interest in and to
any condemnation proceeds and/or awards to which Seller is entitled under or in
connection with the ACTA Condemnation.

            1.3 The Property does not include any permits or entitlements with
respect to Seller's asphalt business at the Property. As a condition to the
Close of Escrow, Buyer and Seller will enter into a "Noncompetition Agreement"
in the form of Exhibit "B" attached hereto, which generally provides that Buyer
shall not carry on any business at or from the Property that involves the
manufacture or sale of asphaltic concrete products. The foregoing prohibition
does not include the manufacture or sale of asphaltic binders as are customarily
manufactured and/or sold in the normal course of the refinery business. Further,
the Grant Deed for the Property will contain a corresponding express use
restriction.

         2. PURCHASE PRICE. The purchase price ("Purchase Price") for the
Property is Two Million Three Hundred Forty-Five Thousand Two Hundred Seventy
Dollars ($2,345,270.00). The Purchase Price shall be paid by Buyer as follows:

            2.1 Within two (2) business days after the "Opening of Escrow"
(hereinafter defined), Buyer shall deposit into "Escrow" One Hundred Thousand
Dollars ($100,000.00) (the "Deposit"), in immediately available funds. Any
failure by Buyer to timely make the Deposit shall be a material default of Buyer
under this Agreement, and shall entitle Seller to terminate and cancel this
Agreement, in addition to all other remedies of Seller. The Deposit will become
non-refundable to Buyer at the expiration of the "Due Diligence Period" (defined
in Section 6.1 below). The Deposit may at Buyer's option be placed in an
interest bearing account approved by Buyer and Seller at Buyer's cost; interest
accrued thereon and risk of loss shall be for the account of Buyer. The term
"Deposit" shall include any interest earned thereon. The Deposit will be applied
to the Purchase Price if the purchase and sale of the Property closes as
contemplated hereunder.

            2.2 At least one (1) business day before the "Closing Date" (defined
in Section 3.2 below), Buyer shall have on deposit in Escrow, in funds available
for disbursement to Seller on the date specified for the "Close of Escrow"
(defined in Section 3.2 below), the balance of the Purchase Price, plus
additional amounts required to pay Buyer's expenses as provided below.

         3. ESCROW; CLOSING DATE

            3.1 Within five (5) business days after the mutual execution of
three (3) copies of this Agreement, the parties shall open an escrow ("Escrow")
at Commerce Escrow Company, 1545 Wilshire Boulevard, Los Angeles, California
90017, Attn: Philip


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Graf ("Escrow Holder"). A fully executed copy (or counterpart executed copies)
of this Agreement shall be deposited with Escrow Holder and shall constitute the
instructions of the parties as to the terms and conditions of Escrow. Escrow
Holder's "General Provisions" are hereby incorporated by reference. In the event
of a conflict between this Agreement and the General Provisions, the terms of
this Agreement shall prevail. As used herein, "Opening of Escrow" means the date
Escrow Holder agrees to act as Escrow Holder in accordance with this Agreement;
"Close of Escrow" means the recording of the Grant Deed in the Official Records
of the County in which the Property is located; "Closing Date" means the date
Close of Escrow occurs; and "Date of Agreement" means the date Buyer and Seller
have executed this Agreement.

            3.2 Close of Escrow shall occur on or before ten (10) business days
following Seller's notice to Buyer of recordation in the Official Records of Los
Angeles County of either an Order of Condemnation or such other appropriate
document(s) with respect to the ACTA Condemnation that divides the Property into
a separate legal lot pursuant to the Subdivision Map Act and local ordinances
implementing same, that can be validly, individually transferred (the
"Subdivision"). Notwithstanding the foregoing, the Close of Escrow shall not
occur prior to expiration of the "Due Diligence Period" (as defined below). In
the event the Subdivision has not occurred by January 1, 2003, this Agreement
shall terminate (except for those provisions which expressly survive
termination) and Escrow Holder shall return the Deposit to Buyer, less title and
escrow charges, if any.

         4. CLOSING COSTS. Seller shall pay the cost of a standard CLTA title
insurance policy for the Property. If Buyer desires extended coverage and/or an
ALTA policy, Buyer shall pay the additional cost of such policy over a CLTA
policy. In any event, Buyer is solely responsible for obtaining any survey
necessary. The escrow fee shall be paid half by Seller and half by Buyer. Seller
shall pay all documentary transfer taxes payable in connection with recording
the Grant Deed. Buyer and Seller shall pay, respectively, Escrow Holder's
customary charges to Buyer and Seller for drafting, recording and miscellaneous
charges.

         5. ELECTION TO EXCHANGE

            5.1 Both Buyer and Seller agree to accommodate each other in
effecting a tax deferred exchange under Internal Revenue Code ss. 1031. Each
party shall have the right, expressly reserved herein, to elect a tax deferred
exchange at any time before the Closing Date (including, without limiting the
foregoing, Seller's right to substitute an accommodating party as seller of all
or any portion of the Property); provided, however, that the sale of the
Property shall not be predicated or conditioned on any exchange, and without in
any way limiting the foregoing, the Close of Escrow shall not be contingent,
delayed or otherwise subject to the closing of any other escrow. Neither party
shall be required to take title to any real property other than the Property, to
accommodate the other party's exchange.

            5.2 If a party elects to effect a tax deferred exchange, the other
party shall promptly execute all amendments to this Agreement, escrow
instructions pertaining to the


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exchange and all other documents as may be necessary to carry out such an
exchange; provided, however, that the accommodating party shall have the right
to approve any and all such documents (which approval shall not be unreasonably
withheld), and the accommodating party shall have no liability to the other
party or to any other person for any act or omission, condition, representation,
warranty, defect in title, or other matter concerning the exchange.

            5.3 Neither party shall be obligated to incur any greater cost or
expense due to the other party's exchange than would have been the case in a
purchase of the Property as otherwise specified in this Agreement. Buyer and
Seller shall each hold the other harmless from any liability, damages, or costs,
including reasonable attorneys' fees, that may arise from the accommodating
party's participation in an exchange.

         6. DUE DILIGENCE; TITLE. Buyer's obligation to purchase the Property is
subject to Buyer's approval, deemed approval or waiver, during the Due Diligence
Period, of the contingencies set forth in Sections 6.2 and 6.3 below, which
approval or waiver shall be given or withheld in Buyer's reasonable discretion.
Buyer shall promptly commence, and diligently in good faith pursue, its due
diligence review hereunder. If, prior to expiration of the Due Diligence Period,
Buyer disapproves or is not deemed to approve any of such contingencies or
Buyer's Board of Directors has not approved this Agreement, then this Agreement
shall terminate without liability of either party therefor (except for those
provisions which expressly survive termination) and Escrow Holder shall return
the Deposit to Buyer, less title and escrow charges, if any.

            6.1 Due Diligence Period. Buyer shall have until 5:00 p.m. on March
15, 2001 (the "Due Diligence Period") within which to make such investigations,
tests and study of the Property as Buyer deems appropriate. Buyer's review of
the Property, including physical inspections, shall be at Buyer's sole cost and
expense.

            6.2 Property Inspections. Buyer, Buyer's representatives, and/or
authorized agents may enter the Property during the Due Diligence Period to make
tests or other studies of the Property; provided, however, that (i) Buyer shall
not interfere with the use of the Property by Seller, (ii) Buyer shall not
conduct any invasive testing without the express prior written consent of
Seller, which consent shall not be unreasonably withheld or delayed, (iii) Buyer
shall pay for all tests and studies, (iv) Buyer shall keep the Property free and
clear of any liens arising out of Buyer's entry onto the Property or the tests
and studies, (v) Buyer shall promptly repair all damage to the Property arising
out of or caused by such entry or the tests and studies, and (vi) Buyer shall
release, defend, indemnify and hold Seller harmless from and against any and all
liabilities, claims, demands, damages or costs of any kind whatsoever, including
but not limited to those caused by Seller's passive negligence (including
attorneys' fees, expert and consultant fees and costs of litigation) arising
from or in connection with such entry or the tests and studies. The foregoing
shall be continuing obligations of Buyer surviving any termination of this
Agreement, and surviving the Close of Escrow and the conveyance of the Property.



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                (a) Buyer shall have until the expiration of the Due Diligence
         Period to deliver to Seller a notice disapproving the Property for
         purchase. Failure to so notify Seller in writing by the end of the Due
         Diligence Period shall be deemed conclusively Buyer's approval of the
         Property for purchase without qualification or condition, and Buyer's
         representation to Seller that Buyer's Board of Directors has approved
         this Agreement and Buyer's purchase of the Property.

                (b) Buyer shall keep the results of all tests and studies
         confidential and shall not disclose the results thereof to any outside
         parties other than its existing or prospective lenders, principals or
         affiliates or as otherwise required by law; provided that each outside
         party shall, prior to its receipt of any such results, agree to keep
         all such information confidential. In the event Buyer or an outside
         party to which Buyer has otherwise disclosed the results of studies or
         tests as permitted by this Agreement is requested to disclose any
         studies or test results under the terms of a valid and effective
         subpoena, order, request for production, interrogatory, investigative
         demand or similar process, Buyer shall promptly notify Seller of the
         existence, terms and circumstances surrounding such request, so that
         Seller may seek an appropriate protective order and/or waive Buyer's
         compliance with the provisions of this Section 6.2(b). If disclosure of
         such information is required in the opinion of Buyer's counsel, Buyer
         may disclose such information, provided that Buyer agrees to cooperate
         with Seller's efforts to obtain an order or other reliable assurance
         that confidential treatment will be accorded to such of the disclosed
         information which Seller designates.

                (c) Buyer shall give Seller not less than two (2) business days
         prior notice of any entry onto the Land or any portion thereof. Said
         notice shall specify the day and time of each such entry and Seller
         may, in Seller's discretion, accompany Buyer during any such entry.

            6.3 Title Condition and Deed.

                (a) Promptly after the Opening of Escrow, Seller shall cause to
         be delivered to Buyer a preliminary title report covering the Land,
         with copies of all documents referenced as exceptions therein (the
         "Report") from Chicago Title Insurance Company (the "Title Company").
         If Buyer elects ALTA coverage, any survey or update required shall be
         furnished by Buyer, at Buyer's sole cost, prior to the Close of Escrow,
         subject to Section 6.3(a). Buyer shall have until seven (7) days after
         its receipt of the Report to deliver to Seller in writing any
         objections to the Property or the condition of title to the Land;
         provided, however, Buyer shall not object to (i) a lien to secure
         payment of real estate taxes, not delinquent; and (ii) matters
         affecting the condition of title suffered or created by, or with the
         consent of, Buyer. Failure of Buyer to



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         object to any exception shown in the Report, by written notice to
         Seller within said seven (7) day period, shall be conclusively deemed
         Buyer's approval of the Report.

                (b) Within five (5) days of Seller's receipt of Buyer's notice
         of objection to any title exception, Seller shall notify Buyer in
         writing of Seller's election whether or not to cure such objection.
         Seller's failure to so notify Buyer shall be deemed Seller's election
         not to cure. Should Seller elect not to cure, then within three (3)
         days of receipt of Seller's notice, Buyer shall elect to either (i)
         terminate this Agreement without any liability of either party
         therefor, or (ii) accept the Property without any reduction of the
         Purchase Price and without liability of Seller. If Seller elects to
         cure, Seller shall do so prior to the Close of Escrow.

                (c) Buyer agrees and acknowledges that unless Seller elects in
         writing to cure, Buyer's sole and exclusive remedy in the event Seller
         elects not to cure any disapproved exception shall be Buyer's election
         of either option (i) or (ii) in Section 6.3(b) above. Buyer's failure
         to notify Seller in writing within the three (3) day period specified
         above of its election of option (i) or (ii) shall be deemed an election
         of option (ii).

                (d) At the Close of Escrow, and as a condition to Closing,
         Seller shall convey the Land to Buyer by Grant Deed, subject only to
         those matters and restrictions of record appearing on the Reports
         approved by Buyer, and to any matters shown on the survey. Title shall
         be evidenced by the willingness of the Title Company or other reputable
         title insurance company to issue its CLTA standard owner's form policy
         of title insurance (or an ALTA extended coverage policy, provided
         Buyer has paid the additional cost thereof)(the "Title Policy") in the
         amount of the Purchase Price, showing title to the Land vested in Buyer
         subject only to recorded exceptions and matters shown on the Report and
         the survey and any exceptions described in Sections 6.3(a)(i) and (ii)
         above.

                (e) The provisions of the foregoing Sections 6.4(a) through (d)
         shall not in any event extend the Due Diligence Period or the Closing
         Date. Without limiting the generality of the foregoing, Buyer
         acknowledges that if the survey is not obtained until after expiration
         of the Due Diligence Period, any matters shown on such survey and
         thereafter raised as exceptions in the Report shall not be subject to
         approval by Buyer.

         7. CONDITION OF PROPERTY; DISCLAIMER; RELEASE. As an essential
inducement to Seller to enter into this Agreement, Buyer acknowledges,
understands and agrees to, as of the date hereof and as of the Closing Date, the
following Sections 7.1 through 7.7:


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            7.1 Disclaimer. Seller hereby disclaims and shall not be liable for
any and all verbal and/or written statements, conversations, representations and
information, if any, made or given by Seller or any of Seller's agents or
employees, or any other person to Buyer, to any agent or employee of Buyer or to
any other person with respect to any aspect or feature of the Property
(including without limitation any information related to the Property's value,
condition, or compliance with laws, the Property's soils and geology, the
existence or availability of any permits or approvals from any governmental
authorities, or the existence of any hazardous substances on the Property). All
such statements, conversations, representations and information, if any, are
merged into and superseded by this Agreement, and Buyer hereby agrees that Buyer
shall not be entitled to rely upon any such statements, conversations,
representations or information except to the extent, if any, specifically and
expressly set forth in this Agreement.

            7.2 Investigation. Buyer acknowledges that by the terms of this
Agreement it is afforded access to the Property and that it shall conduct its
own investigation of the Property. Buyer represents to Seller that as of the
Close of Escrow, Buyer will have made all inquiries, inspections, tests, audits,
studies and analyses that it deems necessary or desirable in connection with
purchasing the Property, and will have approved the results thereof (including
but not limited to engineering tests, environmental assessments and audits, land
use and development entitlements and restrictions, soils and geological reports
and tests and inquiries of governmental authorities). Buyer hereby acknowledges
that it is relying solely on its own independently developed inspections, tests,
audits, studies and investigations conducted in connection with, and on Buyer's
own judgment and verified information with respect to, its purchase of the
Property, and is not relying on any representation or statement of Seller or any
materials, data or other information supplied by Seller.

            Without limiting the generality of the foregoing, Buyer acknowledges
that (i) Buyer and/or its affiliate currently leases the Refinery Land from
Seller, and has occupied and been in possession of the Refinery Land prior to
the date hereof pursuant to the Refinery Lease, and (ii) Buyer and/or its
affiliate is the sublessee of Seller under the Railroad Leases. Buyer represents
and warrants that Buyer is fully familiar with the condition of the Property.

            7.3 Sophistication of Buyer. Buyer is a sophisticated purchaser who
is familiar with the ownership and operation of real estate similar to the
Property and Buyer has or will have adequate opportunity to complete all
physical and financial examinations relating to the acquisition of the Property
hereunder it deems necessary, and will acquire the same solely on the basis of
such examinations and the title insurance protection afforded by the Title
Policy and not on any information provided or to be provided by Seller.

            7.4 Due Diligence Materials. Any information provided or to be
provided with respect to the Property is solely for Buyer's convenience and was
or will be obtained from a variety of sources. Seller has not made any
independent investigation or



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verification of such information and makes no representations as to the accuracy
or completeness of such information. Seller shall not be liable for any
negligent misrepresentation or any failure to investigate the Property nor shall
Seller be bound in any manner by any verbal or written statements,
representations, appraisals, environmental assessment reports, or other
information pertaining to the Property or the operation thereof, furnished by
Seller or by any real estate broker, agent, representative, affiliate, director,
officer, shareholder, employee, servant or other person or entity acting on
Seller's behalf.

            7.5 "AS IS". BUYER IS BUYING THE PROPERTY "AS IS" AND WITHOUT ANY
REPRESENTATIONS OR WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, OF ANY KIND
WHATSOEVER, BY SELLER, ITS AGENTS, BROKERS, CONSULTANTS, COUNSEL, PARENTS,
EMPLOYEES, OFFICERS, DIRECTORS, SHAREHOLDERS, PARTNERS, TRUSTEES OR
BENEFICIARIES OR ANY OTHER PERSON. WITHOUT LIMITING THE GENERALITY OF THE
FOREGOING, BUYER ACKNOWLEDGES THAT SELLER EXPRESSLY DISCLAIMS AND NEGATES, AS TO
THE PROPERTY: (A) ANY IMPLIED OR EXPRESS WARRANTY OF MERCHANTABILITY; (B) ANY
IMPLIED OR EXPRESS WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE; (C) ANY IMPLIED
OR EXPRESS WARRANTY OF CONFORMITY TO MODELS OR SAMPLES OF MATERIALS; AND (D) ANY
IMPLIED OR EXPRESS WARRANTY WITH RESPECT TO (i) THE CONDITION OF THE PROPERTY,
(ii) THE COMPLETENESS OR ACCURACY OF ANY DOCUMENTS DELIVERED TO BUYER BY SELLER,
INCLUDING WITHOUT LIMITATION THE ACREAGE OF THE PROPERTY, OR (iii) THE
PROPERTY'S COMPLIANCE WITH ANY ZONING OR OTHER APPLICABLE RULES, REGULATIONS,
LAWS OR STATUTES, OR THE USES PERMITTED ON, THE DEVELOPMENT REQUIREMENTS FOR, OR
ANY OTHER MATTER OR THING RELATING TO THE PROPERTY OR ANY PORTION THEREOF.

            BUYER ACKNOWLEDGES THAT, TO THE EXTENT REQUIRED TO BE OPERATIVE, THE
DISCLAIMERS OF WARRANTIES CONTAINED IN THIS SECTION 7.5 ARE "CONSPICUOUS"
DISCLAIMERS FOR PURPOSES OF ANY APPLICABLE LAW, RULE, REGULATION OR ORDER.

                Without limiting the generality of the foregoing, Buyer
understands and acknowledges that the Property contains, among other things, an
asphalt plant and associated concrete foundations, an underground tunnel, and
various other improvements and personal property. Buyer acknowledges that except
as provided in the following sentence, Seller has no obligation whatsoever to
remove any improvements or personal property from the Property, but that Seller
has the right, in Seller's sole and absolute discretion, to remove any
improvements or personal property Seller owns prior to or within a reasonable
time after the Close of Escrow. Notwithstanding the foregoing, Seller shall
remove the pile of recycled asphalt products from the Property within 30 days
after the Close of Escrow.


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            7.6 Survival. The above Sections 7.1 through this Section 7.6 shall
survive the termination of this Agreement or the Closing Date and shall not be
deemed to have merged into any of the documents executed or delivered at the
Close of Escrow.

            7.7 Release. Without limiting the foregoing, as a continuing
obligation surviving the Close of Escrow and the conveyance of the Property by
Grant Deed, Buyer shall, from and after the Close of Escrow, release, defend,
indemnify and hold harmless Seller and "Seller's Releasees" (as hereinafter
defined) from and against any and all loss, damage, claim, costs and expense
(including without limitation actual attorneys' fees, charges and costs) and any
other liability whatsoever, whether foreseen or unforeseen, arising out of or
relating to the condition of the Property or any portion thereof, including
without limitation the Refinery Land. "Seller's Releasees" shall be Seller and
the successors and assigns of Seller (including without limitation an
accommodation party substituted as Seller for purposes of effecting an
exchange), the officers, directors, agents, employees, attorneys, stockholders,
and the parents, subsidiaries and affiliated companies of Seller and its
successors and assigns, and their respective officers, directors, agents,
employees, attorneys, stockholders, subsidiary and affiliated companies, and
each of them. Without limiting the foregoing, from and after the execution of
this Agreement, the provisions of this Section 7.7 shall continue to be
effective with respect to each Seller's Releasee irrespective of whether
thereafter such Seller's Releasee assigns or has purported to assign or
otherwise dispose of its interest or any portion of its interest, under this
Agreement, or in the Property. The foregoing release and indemnity is in
addition to, and shall not be deemed to limit in any way any indemnity or
release of Seller as lessor as set forth in the Refinery Lease.

            Buyer, on behalf of itself and its successors and assigns, hereby
assumes the above-mentioned risks and agrees that the aforesaid release shall
apply to all unknown or unanticipated results of the transactions and
occurrences described above, as well as those known and anticipated, and upon
advice of legal counsel, Buyer, on behalf of itself and its successors and
assigns does hereby waive any and all rights under California Civil Code
ss.1542, which Section has been duly explained, and reads as follows:

                "A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR
         DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF EXECUTING
         THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY AFFECTED HIS
         SETTLEMENT WITH THE DEBTOR."

         8. TAXES, PRORATIONS AND OTHER COSTS.

            8.1 All current and nondelinquent installments of real property
taxes, personal property taxes and assessments on the Property, rent due under
the Railroad Leases and the Refinery Lease, and any other items to be prorated
shall be prorated through Escrow as of the Closing Date. If any such items
cannot be accurately calculated on the Closing Date,



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they shall be prorated on an estimated basis at the Closing and re-prorated as
soon after the Closing as feasible, or prorated after Escrow. Without limiting
the foregoing, Buyer shall, from and after the Close of Escrow, release, defend,
indemnify and hold harmless Seller and Seller's Releasees from and against any
and all loss, damage, claim, costs and expense (including without limitation
actual attorney's fees, charges and costs) and any other liability whatsoever,
whether foreseen or unforeseen, arising out of or relating to the tax default
for Assessor's Parcel Nos. 7426-028-004, 8900-763-379, and 8900-547-299 and 300.
The provisions of this Section 8 shall survive the Close of Escrow.

            8.2 At the Closing, Buyer shall credit Seller for the value of the
remaining term of the Refinery Lease, which, for the purposes of this Agreement,
shall be deemed to be $225,000.00.

         9. RAILROAD LEASES. Seller and Buyer understand that the assignment of
the Railroad Leases requires the prior written consent of SPT. Buyer will
cooperate with Seller in attempting to obtain such consent. Seller makes no
representation or warranty whatsoever, whether expressed or implied, regarding
its ability to obtain such consent or whether such consent can or will be
obtained. In the event the consent of SPT is not obtained prior to the Closing,
the parties shall nevertheless close Escrow without the Assignment and
Assumption of Leases, and Seller"s existing sublease of the Railroad Leases to
Huntway Partners L.P. shall not be affected.

            9.1 If Seller obtains the consent of SPT to assign the Railroad
Leases, then at Closing, (i) Buyer shall, pursuant to the Assignment and
Assumption of Leases, assume all of Seller's obligations under the Railroad
Leases accruing from and after the Close of Escrow and agree to indemnify and
hold Seller harmless from any and all claims and damages that arise out of
events or incidents on or about the Property occurring from and after the Close
of Escrow or that in any way arise out of Buyer's ownership of the Property
and/or the Railroad Leases, and (ii) Seller shall, pursuant to the Assignment
and Assumption of Leases, assign in writing all of Seller's obligations under
the Railroad Leases accruing from and after the Close of Escrow and Seller shall
indemnify and hold Buyer harmless from any and all claims and damages that arise
out of events or incidents on or about the Property occurring prior to the Close
of Escrow or that arise out of Seller's ownership of the Property.

            9.2 In the event SPT requires a form of Assignment of Lease that
does not provide for a release of Seller from the duties and obligations of the
lessee under the Railroad Leases, then at Closing, in lieu of the Assignment and
Assumption of Leases attached hereto, Buyer and Seller shall enter into an
Indemnification Agreement in the form of Exhibit "D" hereto. Such
Indemnification Agreement provides, among other things, that Buyer shall not
amend, extend or in any way assign, sublease or transfer the Railroad Leases
without the prior written consent of Seller as set forth therein (or SPT's
express release of Seller from the Railroad Leases), and that Seller shall
receive copies of all correspondence and notices regarding the Railroad Leases.



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            9.3 Notwithstanding any other provision of this Agreement, nothing
contained in this Agreement is intended to limit or modify any obligations of
Buyer or any of its affiliates as subtenant(s) under the Railroad Leases.

         10. CLOSING; DELIVERIES BY SELLER AND BUYER.

            10.1 On or before the Closing Date, except as provided below, Seller
shall deliver or cause to be delivered to Escrow Holder the following, executed
and acknowledged where appropriate:



                (a) A Grant Deed for the Land;

                (b) The Noncompetition Agreement in the form of Exhibit "B"
         hereto;

                (c) Subject to Section 9 above, Assignments and Assumptions of
         the Railroad Leases in the form of Exhibit "C" hereto or such other
         form acceptable to SPT, and, if required, the Indemnification Agreement
         in the form of Exhibit "D" hereto;

                (d) An affidavit that Seller is not a "foreign person" Within
         the meaning of Section 1445(f)(3) of the Internal Revenue Code, as
         amended;

                (e) A California Form 590-DRE; and

                (f) Any other documents, instruments or agreements reasonably
         necessary to close the transaction contemplated by this Agreement.

            10.2 On or before the Closing Date, Buyer shall deliver to Seller or
Escrow Holder the following, executed and acknowledged where appropriate:

                (a) The Purchase Price and any additional funds required to pay
         Buyer's expenses hereunder;

                (b) The Noncompetition Agreement in the form of Exhibit "B"
         hereto;

                (c) Subject to Section 9 above, Assignments and Assumptions of
         the Railroad Leases in the form of Exhibit "C" hereto or such other
         form acceptable to SPT, and, if required, the Indemnification Agreement
         in the form of Exhibit "D" hereto; and

                (d) Any other documents, instruments or agreements reasonably
         necessary to close the transaction contemplated by this Agreement.


                                       11

<PAGE>   12
            10.3 Seller and Buyer acknowledge that SPT may require a specific
form of assignment and assumption of the Railroad Leases. The parties agree that
in the event the SPT form does not include a release of Seller from the
obligations of lessee under the Railroad Leases and an indemnification
substantially similar to Section 2 of Exhibit "B" hereto, the parties will
execute a separate agreement at Closing containing such provisions.

         11. DISBURSEMENTS AND OTHER ACTIONS BY ESCROW HOLDER. Upon the Close of
Escrow, Escrow Holder shall perform the following in the manner hereinbelow
indicated:

                (a) Disburse to Seller the Purchase Price, less all items
         chargeable to Seller's account pursuant to this Agreement;

                (b) Cause the Grant Deed and any other documents that the
         parties hereto may mutually direct to be recorded in the Official
         Records of the County in which the Property is located;

                (c) Cause the Title Company to deliver the Title Policy to
         Buyer;

                (d) Deliver to Seller and Buyer conformed copies of all
         documents recorded at the Close of Escrow; and

                (e) Deliver to the appropriate parties any other documents or
         instruments to be delivered through Escrow pursuant to the terms
         hereof.

         12. POSSESSION, RISK OF LOSS. Possession of the Property shall be given
to Buyer at the Close of Escrow. All risk of loss or damage with respect to the
Property shall pass from Seller to Buyer at the Close of Escrow.

         13. BROKERAGE COMMISSIONS. Buyer and Seller hereby acknowledge and
represent that there are no broker's commissions or finder's fees due in
connection with this transaction. Buyer and Seller shall each hold harmless and
indemnify the other from any claims of brokers, agents or finders, licensed or
otherwise, claiming through, under or by reason of the conduct of the
indemnifying party with respect to the transaction contemplated hereunder.

         14. LIQUIDATED DAMAGES. SELLER AND BUYER AGREE THAT THE DAMAGES THAT
WOULD BE SUFFERED BY SELLER IN THE EVENT OF A DEFAULT BY BUYER HEREUNDER WOULD
BE EXTREMELY DIFFICULT AND IMPRACTICABLE TO ASCERTAIN, AND THAT THE DEPOSIT
REPRESENTS THE REASONABLE ESTIMATE BY THE PARTIES OF THE AMOUNT OF DAMAGES THAT
SELLER WOULD SUFFER BY REASON OF BUYER'S DEFAULT, CONSIDERING ALL OF THE
CIRCUMSTANCES EXISTING ON THE DATE OF THIS AGREEMENT,



                                       12
<PAGE>   13


INCLUDING THE RELATIONSHIP OF THE SUM TO THE RANGE OF HARM TO SELLER THAT
REASONABLY COULD BE ANTICIPATED, AND THE ANTICIPATION THAT PROOF OF ACTUAL
DAMAGES WOULD BE COSTLY, IMPRACTICAL OR INCONVENIENT, AND PARTICULARLY IN VIEW
OF THE FACT THAT SELLER IS TAKING THE PROPERTY OFF THE MARKET, WHICH SELLER
WOULD NOT DO BUT FOR THE AGREEMENT OF BUYER TO PURCHASE THE PROPERTY.
ACCORDINGLY, IN THE EVENT OF A DEFAULT BY BUYER HEREUNDER, SELLER SHALL RECEIVE
AND RETAIN THE DEPOSIT AS LIQUIDATED DAMAGES. SAID SUM SHALL BE IN ADDITION TO
AND SHALL NOT BE DEEMED TO INCLUDE ANY ATTORNEYS' FEES WHICH MAY BECOME DUE
SELLER PURSUANT TO SECTION 19 HEREOF. IF AND WHEN SELLER BECOMES ENTITLED TO
RECEIVE SUCH LIQUIDATED DAMAGES IN ACCORDANCE WITH THE PROVISIONS HEREOF, ESCROW
HOLDER IS HEREBY INSTRUCTED TO IMMEDIATELY DELIVER THE DEPOSIT TO SELLER. BY
INITIALING THIS PROVISION IN THE SPACE BELOW, SELLER AND BUYER EACH
SPECIFICALLY AFFIRMS ITS RESPECTIVE OBLIGATIONS UNDER THIS SECTION 14.

            Seller                                Buyer
            Initial here: /s/ MY                  Initial here: /s/ SPP
                         -------                                -------

         15. LIMITATION OF LIABILITY. No member, partner or shareholder in or
agent of Seller, nor any advisor, trustee, director, officer, employee,
beneficiary, shareholder, member, partner, participant, representative or agent
of any partnership, limited liability company, corporation, trust or other
entity that has or acquires a direct or indirect interest in Seller, shall have
any personal liability, directly or indirectly, under or in connection with this
Agreement or any agreement entered into under or pursuant to this Agreement, or
any amendment to any of the foregoing made heretofore or hereafter. Buyer and
its successors and assigns and, without limitation, all other persons and
entities, shall look solely to Seller's assets for the payment of any claim or
for any performance, and Buyer, on behalf of itself and its successors and
assigns, hereby waives any and all such personal liability. In no event shall
Buyer be entitled to punitive or consequential damages under this Agreement. The
foregoing shall be in addition to, and not in limitation of, any further
limitation of liability that might otherwise apply (whether by reason of Buyer's
waiver, relinquishment or release of any applicable rights or otherwise).

         16. NOTICES. All notices, demands, and requests under this Agreement by
either party shall be hand delivered or sent by United States first class mail,
certified or express, postage prepaid, or by a national express courier such as
Federal Express, U.P.S., etc., or sent by facsimile transmission with
confirmation of receipt, and addressed to the parties as follows:



                                       13
<PAGE>   14


            "Seller"                     CalMat Co.
                                         3200 San Fernando Road
                                         Los Angeles, CA 90065
                                         Attention: Brian W. Ferris
                                         Telephone: (323) 258-2777
                                         Fax No.: (323) 255-0722


            With a copy to:              CalMat Properties Co.
                                         8885 Rio San Diego Drive, Suite 240
                                         San Diego, CA 92108
                                         Attention: Patricia Schreibman
                                         Telephone: (619) 298-5800
                                         Fax No.:   (619) 298-3211


            "Buyer"                      Huntway Refining Company
                                         1651 Alameda Street
                                         Wilmington, CA 90744
                                         Attention: Steve Piatek, Vice President
                                                    and General Counsel
                                         Telephone: (310) 518-4000
                                         Fax No.: (310) 518-1197


            With a copy to:              Huntway Refining Company
                                         25129 The Old Road, Suite 322
                                         Newhall, CA 91381
                                         Attention: Earl Fleisher, CFO
                                         Telephone: (661) 254-1220
                                         Fax No.: (661) 286-1588


Notices, demands, and requests served in the above manner shall be considered
sufficiently given or served for all purposes at the time the notice, demand or
request is actually delivered to the addresses shown above during normal
business hours, or otherwise the next business day.

         17. ASSIGNMENT. Buyer shall not assign this Agreement, or any rights
hereunder to any other person or entity without the prior written consent of
Seller, which consent may be granted or withheld in Seller's reasonable
discretion. Any assignment or purported assignment which has not received
Seller's prior written consent shall be null and void and of no force or effect
whatsoever. Buyer shall remain primarily liable for the performance of this
Agreement by any assignee. Subject to the foregoing limitations, this Agreement
shall be binding upon and inure to the benefit of the successors and assigns of
the respective parties hereto. Except for an assignment with Seller's prior
written consent, the provisions of this Agreement are for the sole benefit of
the parties hereto, and are not for the benefit, directly or indirectly, of any
other person or entity.



                                       14



<PAGE>   15


         18. INTERPRETATION. Unless the context of this Agreement clearly
requires otherwise, plural and singular numbers shall each be deemed to include
the other; the masculine, feminine and neuter genders shall each be deemed to
include the others; "or" is not exclusive; and "includes" and "including" are
not limiting. Section headings are included in this Agreement as a matter of
convenience only, and are not a part of this Agreement and shall not be used in
its interpretation. Time is of the essence for each and every term, condition,
covenant, obligation and provision of this Agreement. This Agreement has been
negotiated at arm's length and between persons sophisticated and knowledgeable
in the matters dealt with in this Agreement. In addition, each party has been or
has had the opportunity to be represented by experienced and knowledgeable
counsel. Accordingly, any rule of law (including California Civil Code ss.1654)
or legal decision that would require interpretation of any ambiguities in this
Agreement against the party that drafted it is not applicable and is waived. The
provisions of this Agreement shall be interpreted in a reasonable manner to
effect the purpose of the parties and this Agreement.

         19. ATTORNEYS' FEES. Should any party hereto institute any action or
proceeding to enforce any provision hereof by reason of the alleged breach of
this Agreement, the prevailing party shall be entitled to receive from the
losing party such amount as the court may adjudge to be reasonable attorneys'
fees, expert fees, and consultant fees for services rendered to the prevailing
party, and other costs of litigation.

         20. CONFLICTS. In the event of a conflict between the provisions of
this Agreement and the provisions of any other document(s) executed or purported
to be executed between the parties prior to the date hereof, the provisions
contained in this Agreement shall in all instances govern and prevail.

         21. SEVERABILITY. In the event any portion of this Agreement shall be
declared by any court of competent jurisdiction to be invalid, illegal or
unenforceable, such portion shall be severed from this Agreement and the
remaining parts hereof shall remain in full force and effect as fully as though
such invalid, illegal or unenforceable portion had never been part of this
Agreement, provided the remaining Agreement can be reasonably and equitably
enforced.

         22. REQUIRED ACTIONS OF BUYER AND SELLER. Buyer and Seller agree to
execute all such instruments and documents and to take all actions (including
the deposit of funds in addition to such funds as may be specifically provided
for herein) as may be required in order to consummate the purchase and sale
herein contemplated and shall use their best efforts to accomplish the Close of
Escrow in accordance with the provisions hereof.

         23. GOVERNING LAW AND VENUE. The validity of this Agreement and any of
its terms or provisions, as well as the rights and duties of the parties
hereunder, shall be interpreted and construed pursuant to and in accordance with
the laws of the State of


                                       15

<PAGE>   16


California. The parties select Los Angeles County, California as the proper and
sole venue for any action filed to enforce, construe or interpret this
Agreement.

         24. ENTIRE AGREEMENT. This Agreement constitutes the final, complete
and exclusive statement of terms of the agreement between the parties pertaining
to the subject matter of this Agreement and supersedes all prior and
contemporaneous understandings or agreements of the parties. No party has been
induced to enter into this Agreement by, nor is any party relying on, any
representation or warranty outside those expressly set forth in this Agreement.

         25. COUNTERPARTS. This Agreement may be executed in counterparts, each
of which shall be deemed an original, but all of which, together, shall
constitute one and the same instrument.

         26. CONFIDENTIALITY; RETURN OF PROPRIETARY INFORMATION.

             26.1 Buyer shall treat all information of whatsoever nature
provided to it under the terms of this Agreement ("Proprietary Information") as
confidential and Buyer shall not disclose such Proprietary Information to third
parties not involved in Buyer's evaluation of the Property, without the prior
written approval of Seller, unless Buyer is legally required to provide such
information to a governmental agency or pursuant to legal process. Proprietary
Information shall not include any information which is, or becomes, generally
available to the public other than as a result of a disclosure by Buyer, or was
in Buyer's possession prior to it being furnished by Seller. The provisions of
this Section 26.1 shall expire upon the Close of Escrow and conveyance of the
Property to Buyer hereunder. Notwithstanding the foregoing, Section 6.2(b) above
shall govern the disclosure of tests and studies.

             26.2 In the event the purchase and sale contemplated hereby fails
to close for any reason whatsoever, Buyer shall return to Seller, or cause to be
returned to Seller, all Proprietary Information, and shall deliver to Seller all
reports and analyses of the Property prepared by or at the request of Buyer.
Further, Buyer agrees not to use or allow to be used any Proprietary Information
for any purpose other than to determine whether to proceed with the contemplated
purchase, or if same is consummated, in connection with the ownership or
operation of the Property post-Closing. The provisions of this Section 26.2
shall survive the Closing Date or the termination of this Agreement.

         27. SELLER'S OPTION TO LEASE. After the Closing Date, Seller shall have
the right to remain in occupancy of that portion of the Land that was not
subject to the Refinery Lease, on a month to month basis or such other longer
term as is acceptable to Seller (up to a maximum of one year), at a rate of
$1.00 per month for the first fall calendar month after the Close of Escrow, and
thereafter at a mutually acceptable market rate. At Buyer's request, Seller
shall execute a lease on such terms and conditions as are contained in Seller's
standard


                                       16

<PAGE>   17


form of lease, or in the American Industrial Real Estate Association (AIR) form
of Standard Industrial/Commercial Single Tenant Lease.

         28. APPROVAL OF SELLER'S MANAGEMENT. This Agreement, and the purchase
and sale of the Property hereunder, are subject to the approval of Seller's
Board of Directors and/or appropriate managerial authorities. In the event such
approvals are not obtained on or before 60 days after the Opening of Escrow,
this Agreement shall terminate (except for those provisions hereof that
expressly survive termination) without liability of either party therefor, and
Escrow Holder shall return the Deposit to Buyer.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
day and year first written above.


                "SELLER"           CALMAT CO., a Delaware corporation

                                   By: /s/ MICHAEL LITON
                                      ------------------------------------------
                                      Title: Vice President Business Development
                                            ------------------------------------


                "BUYER"            HUNTWAY REFINING COMPANY,
                                   a Delaware corporation

                                   By: /s/ STEVE P. PIATEK
                                      ------------------------------------------
                                      Title: Vice President and General Counsel
                                            ------------------------------------



                                       17



<PAGE>   18


                                  EXHIBIT "A"

                               DESCRIPTION OF LAND

LOT 1 OF TRACT 13038, IN THE CITY OF LOS ANGELES, COUNTY OF LOS ANGELES, STATE
OF CALIFORNIA, AS PER MAP RECORDED IN BOOK 254, PAGE 20 OF MAPS, IN THE OFFICE
OF THE COUNTY RECORDER OF SAID COUNTY.

EXCEPT THEREFROM THAT PORTION AS CONVEYED TO THE CITY OF LOS ANGELES, A
MUNICIPAL CORPORATION BY DEED RECORDED JULY 28, 1997 AS INSTRUMENT NO.
97-1142776, OFFICIAL RECORDS.

SUBJECT TO ALL COVENANTS, CONDITIONS, RESTRICTIONS, EASEMENTS, ENCUMBRANCES AND
RIGHTS OF RECORD.




<PAGE>   19


                                  EXHIBIT "B"

                            NONCOMPETITION AGREEMENT

         THIS NONCOMPETITION AGREEMENT ("Agreement") is made and entered into as
of the ______ day of __________, by and between HUNTWAY REFINING COMPANY, a
Delaware corporation ("Huntway") and CALMAT CO., a Delaware corporation
("CalMat").

                                    RECITALS

         A. CalMat is in the business of manufacturing and selling asphalt and
asphaltic concrete products.

         B. Pursuant to that certain Purchase and Sale Agreement dated
_________, 2000 (the "Purchase and Sale Agreement"), CalMat agreed to sell to
Huntway, and Huntway agreed to purchase from CalMat, certain real property
located in Wilmington, California, on the terms and conditions set forth therein
(the "Property").

         C. For valuable consideration, and in consideration for Calmat's
agreement to enter into the Purchase and Sale Agreement and consummate the sale
of the Property to Huntway, Huntway has agreed to enter into a covenant not to
compete with CalMat on the terms and conditions hereinafter set forth.

                                    AGREEMENT

         1. For valuable consideration, receipt of which is hereby acknowledged,
Huntway, on behalf of itself, its subsidiaries, parents, and any other entity
directly or indirectly controlling, controlled by or under common control with
Huntway, hereby agrees to refrain from carrying on a business involving the
manufacture, marketing or sale of asphaltic concrete products at, from or in
connection with the Property, for a period of fifty (50) years from the date
hereof, so long as CalMat, or Vulcan Materials Company ("Vulcan") or any
affiliate of CalMat or Vulcan (individually, a "Beneficiary" or collectively,
"Beneficiaries") or any person deriving title from a Beneficiary carries on a
like business in the State of California. For purposes of this Agreement, the
term "affiliate" shall mean any subsidiary of CalMat or Vulcan, or a parent
entity of Calmat or Vulcan, or any other entity directly or indirectly
controlling, controlled by, or under common control with CalMat or Vulcan. The
foregoing prohibition shall not include the manufacture or sale of such
asphaltic binders as are customarily manufactured and/or sold in the normal
course of the refinery business. The phrase "carry on a business" shall include,
but not be limited to, doing, or entering into or proposing to enter into, any
agreement or arrangement to do or cause to be done, any of the following listed
acts:



<PAGE>   20


                (a) Carrying on or engaging in any such business as a principal,
or on his or its own account; or solely or jointly with others as a director,
officer, agent, employee, consultant, partner (general or limited), stockholder
or holder of an equity, security or interest in excess of two percent (2%); or

                (b) Carrying on or engaging in any activities or negotiations
with respect to the acquisition or the disposition of any such business as agent
or principal; or

                (c) Lending credit or money for the purpose of establishing or
operating any such business, except the extending or credit to customers in the
ordinary course of the refinery business as conducted by Huntway prior to the
date hereof; or

                (d) Giving advice to any other person, firm, association or
corporation engaging in any such business, except the giving of advice to
customers in the ordinary course of the refinery business as conducted by
Huntway prior to the date hereof; or

                (e) Lending or allowing his or its name or reputation to be used
in any such business, except to customers in the ordinary course of the refinery
business as conducted by Huntway prior to the date hereof; or

                (f) Allowing his or its skill, knowledge or experience to be
used in any such business, except the extending of skill, knowledge or
experience to customers in the ordinary course of the refinery business as
conducted by Huntway prior to the date hereof.

         2. It is the intent of the parties hereto that the provisions of this
Agreement shall be enforced to the fullest extent permissible under the laws and
public policies of the State of California. Accordingly, if at any time a court
of competent jurisdiction determines that any of the restrictions set forth in
this Agreement are invalid or unenforceable (whether because of excessive
duration, scope of activities covered, geographical area covered or otherwise),
in whole or in part, then this Agreement shall be deemed amended to delete
therefrom or reform the portion of the restrictions thus determined to be
invalid or unenforceable to the extent necessary, and only to the minimum extent
necessary, to make it valid and enforceable.

         3. The parties acknowledge and agree that upon a breach by Huntway of
any of the provisions of this Agreement, CalMat and/or Vulcan shall be entitled
to injunctive relief, as a remedy at law would be inadequate and insufficient;
provided, however, CalMat's and/or Vulcan's election to pursue such injunctive
relief shall not in any way be deemed to limit or waive such party's right to
recover damages or pursue any other remedy which may be available to it under
law or equity.

         4. Should any party hereto institute any action or proceeding to
enforce any provision hereof by reason of the alleged breach of this Agreement,
the prevailing party shall be entitled to receive from the losing party such
amount as the court may adjudge to be reasonable attorneys' fees for services
rendered to the prevailing party.




                                       2
<PAGE>   21


         5. All notices, demands, requests, and notices under this Agreement by
either party shall be hand delivered or sent by Federal Express, or other
similar delivery service, or certified mail postage prepaid, addressed to the
parties as follows:

             "Huntway":                  Huntway Refining Company
                                         1651 Alameda Street
                                         Wilmington, CA 90744
                                         Attention: Steve Piatek, Vice President
                                                    and General Counsel
                                         Telephone: (310) 518-4000
                                         Fax No.:   (310) 518-1197

             "CalMat"                    Vulcan Materials Company,
                                         Western Division
                                         3200 San Fernando Road
                                         Los Angeles, CA 90065
                                         Attention: Legal Department
                                         Telephone: (323) 258-2777
                                         Fax No.: (323) 255-0722

         Notices, demands, and requests served in the above manner shall be
considered sufficiently given or served for all purposes under this Agreement at
the time the notice, demand or request is delivered to the addresses shown
above.

         6.  In the event of a conflict between the provisions of this Agreement
and the provisions of any other documents executed or purported to be executed
between the parties prior to the date hereof, the provisions contained in this
Agreement shall in all instances govern and prevail.

         7.  Time is of the essence for each and every term, condition,
covenant, obligation, and provision of this Agreement.

         8.  This Agreement shall be governed by and construed in accordance
with the laws of the State of California. If an action or proceeding is
initiated in connection with, under, or with respect to this Agreement, the
venue shall be Los Angeles County, California.

         9.  This Agreement shall be construed fairly as to all parties and not
in favor of or against any party, regardless of which party prepared this
Agreement.

         10. This Agreement contains the entire agreement among the parties
hereto, and no addition or modification of any term or provision shall be
effective unless set forth in writing, signed by all parties.


                                       3
<PAGE>   22


         IN WITNESS WHEREOF, the parties executed this Agreement as of the day
and year first above written.


             "HUNTWAY"                   HUNTWAY REFINING COMPANY

                                         By:
                                            ------------------------------------


             "CALMAT"                    CALMAT CO.

                                         By:
                                            ------------------------------------


                                       4
<PAGE>   23



                                  EXHIBIT "C"

                       ASSIGNMENT AND ASSUMPTION OF LEASES

         THIS ASSIGNMENT AND ASSUMPTION of Leases ("Assignment"), dated for
identification purposes only __________________, is made and entered into by
and between CALMAT CO., a Delaware corporation ("Assignor") and ________________
____________________, a ______________________ ("Assignee").

                                    RECITALS

         A. Assignor and Assignee are parties to that certain Purchase and Sale
Agreement and Joint Escrow Instructions dated _________________, 2000 ("Purchase
Agreement") whereby Assignor, as seller, agreed to sell to Assignee, as buyer,
certain real property as set forth therein (the "Property"). The Purchase
Agreement is incorporated herein by this reference as though set forth in full.
All capitalized terms not defined herein shall have the definitions set forth in
the Purchase Agreement.

         B. Assignor desires to assign to Assignee, as of the Closing Date,
Assignor's interest in the "Railroad Leases," as defined in the Purchase
Agreement. Assignee desires to accept such assignment and assume the obligations
of lessee under the Railroad Leases.

         C. For and in consideration of the consummation of the transactions
specified in the Purchase Agreement and in order to consummate such transactions
as required by the Purchase Agreement, Assignor and Assignee enter into and
execute this Assignment.

                            ASSIGNMENT AND ASSUMPTION

         1. ASSIGNMENT AND ASSUMPTION. For valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, Assignor hereby transfers,
grants, conveys and assigns to Assignee all of Assignor's right, title and
interest in, to and under the Railroad Leases, and Assignee hereby accepts such
assignment and assumes and agrees with Assignor to perform and comply with and
to be bound by all terms, covenants, agreements, provisions and conditions of
the Railroad Leases on and after the Closing Date, in the same manner and with
the same force and effect as if Assignee had originally executed the Railroad
Leases. This Assignment is made without any representations or warranties
whatsoever, express or implied.

         2. INDEMNIFICATION. Assignor shall indemnify, defend and hold harmless
Assignee and Assignee's affiliates, and their respective officers, directors,
trustees, shareholders, partners, members, employees, agents, attorneys,
successors and assigns (collectively, the "Assignee Indemnitees"), from and
against any and all liabilities, losses, damages, costs and expenses (including
without limitations, attorneys fees and costs) arising out of any action or
cause of action accruing under the Railroad Leases prior to the Closing Date
(excluding actions arising out of the gross negligence or willful misconduct of
the Assignee Indemnitees). Assignee shall indemnify, defend and hold harmless
Assignor and




<PAGE>   24


Assignor's affiliates, and their respective officers, directors, trustees,
shareholders, partners, members, employees, agents, attorneys, successors and
assigns (collectively, the "Assignor Indemnitees"), from and against all
liabilities, losses, damages, costs, and expenses (including without limitation,
attorneys fees and costs) arising out of any action or cause of action accruing
under the Railroad Leases on or after the Closing Date (excluding actions
arising out of the gross negligence or willful misconduct of the Assignor
Indemnitees).

         3. ATTORNEYS' FEES. In the event of any litigation or proceeding
between the parties hereto for breach of or to enforce any provision or right
hereunder, the unsuccessful party shall pay to the successful party all costs
and expenses, expressly including but not limited to, reasonable attorneys' fees
incurred by the successful party in connection with such action. The successful
party shall be that party who, in the light of the issues litigated and the
court's decisions on those issues, was more successful in the action. The party
who was more successful need not be determined to be the party who recovers a
judgment. An action shall include proceedings in bankruptcy court.

         4. SUCCESSORS. This Assignment shall be binding upon and inure to the
benefit of each of the parties hereto and to their respective successors and
assigns.

         5. FURTHER ACTION. Assignor and Assignee shall at any time, or from
time to time after the execution of this Assignment and whether before or after
the Close of Escrow, upon request of the other, execute and deliver such further
documents and do such further acts and things as such party may reasonably
request in order to fully effect the purpose of this Assignment.

         6. COUNTERPARTS. This Assignment may be executed in any number of
counterparts, each of which shall be deemed an original, and all of which when
taken together shall constitute but one and the same agreement.

         7. GOVERNING LAW. This Assignment shall be governed by and construed in
accordance with the laws of the State of California.

         8. MODIFICATIONS. This Assignment may not be altered, amended, changed,
terminated or modified in any respect or particular, unless the same shall be in
writing and signed by the party to be charged.

         9. SEVERABILITY. Wherever possible, each provision of this Assignment
shall be interpreted in such a manner as to be valid under applicable law, but
if any provision of this Assignment shall be invalid or prohibited thereunder,
such provision shall be effective to the extent of such prohibition without
invalidating the remainder of such provision or the remaining provisions of this
Assignment which shall remain fully binding and in full force and effect.



                                       2
<PAGE>   25


         10. HEADINGS. The headings of the paragraphs of this Assignment are
inserted solely for convenience of reference and are not a part of, and are not
intended to govern, limit or aid in the construction of, any term or provision
hereof.

         IN WITNESS WHEREOF, the Parties hereto have executed this Assignment
effective as of the date first above written.


                                         "ASSIGNOR"

                                         CALMAT CO., a Delaware corporation


                                         By:
                                            ------------------------------------
                                            Title:
                                                  ------------------------------

                                         "ASSIGNEE"

                                         ---------------------------------------

                                         By:
                                            ------------------------------------
                                            Title:
                                                  ------------------------------



                                       3
<PAGE>   26


                                  EXHIBIT "D"

                           INDEMNIFICATION AGREEMENT

         THIS INDEMNIFICATION AGREEMENT ("Agreement"), dated for identification
purposes only _________________________, is made and entered into by and between
CALMAT CO., a Delaware corporation ("Assignor") and _________________________, a
___________________ corporation ("Assignee").

                                    RECITALS

         A. Assignor and Assignee are parties to that certain Purchase and Sale
Agreement and Joint Escrow Instructions dated ________________, 2000 ("Purchase
Agreement") with respect to certain real property as set forth therein (the
"Property"). The Purchase Agreement is incorporated herein by this reference as
though set forth in full. All capitalized terms not defined herein shall have
the definition set forth in the Purchase Agreement.

         B. In connection with the Closing pursuant to the Purchase Agreement,
Assignor has assigned or will assign to Assignee, as of the Closing Date,
Assignor's interest as lessee in (i) that certain Commercial Lease No. 194292
dated April 14, 1981 between Southern Pacific Transportation Company ("SPT"), as
lessor, and Huntmix, Inc. ("Huntmix"), as lessee; and (ii) that certain
Industrial Lease No. 194293 dated April 14, 1981 between SPT as lessor and
Huntmix as lessee (together, the "Railroad Leases"). The Railroad Leases are
incorporated herein by this reference as though set forth in full. Assignee has
accepted or will accept such assignment and assume the obligations of the lessee
under the Railroad Leases as of the Closing Date.

         C. For and in consideration of the consummation of the transactions
specified in the Purchase Agreement and in order to consummate such transactions
as required by the Purchase Agreement, Assignor and Assignee enter into and
execute this Agreement.

                                    AGREEMENT

         1. ASSIGNMENT AND ASSUMPTION. Assignor has heretofore assigned to
Assignee all of Assignor's right, title and interest in, to and under the
Railroad Leases, and Assignee has heretofore accepted such assignment. Assignee
hereby assumes and agrees with Assignor to perform and comply with and to be
bound by all terms, covenants, agreements, provisions and conditions of lessee
under the Railroad Leases on and after the Closing Date, in the same manner and
with the same force and effect as if Assignee had originally executed the
Railroad Leases.




<PAGE>   27


         2. INDEMNIFICATION. Assignor hereby agrees to indemnify, defend and
hold harmless Assignee and Assignee's affiliates, and their respective officers,
directors, trustees, shareholders, partners, members, employees, agents,
attorneys, successors and assigns (collectively, "Assignee Indemnitees"), from
and against any and all liabilities, losses, damages, costs and expenses
(including without limitation attorneys fees and costs) arising out of any
action or cause of action accruing under the Railroad Leases prior to the
Closing Date (excluding actions arising out of the gross negligence or willful
misconduct of Assignee Indemnitees, or arising out of Assignee's acts or
omissions as subtenant under the Railroad Leases prior to the Closing Date).
Assignee hereby agrees to indemnify, defend and hold harmless Assignor and
Assignor's affiliates, and their respective officers, directors, trustees,
shareholders, partners, members, employees, agents, attorneys, successors and
assigns (collectively, "Assignor Indemnitees"), from and against all
liabilities, losses, damages, costs, and expenses (including without limitation
attorneys fees and costs) arising out of any action or cause of action accruing
under the Railroad Leases on or after the Closing Date, and/or arising out of
Assignee's acts or omissions as subtenant under the Railroad Leases prior to the
Closing Date (excluding actions arising out of the gross negligence or willful
misconduct of Assignor Indemnitees).

         3. NO FURTHER ACTIONS REGARDING RAILROAD LEASES. Assignee hereby agrees
not to amend, extend or in any way assign, sublease or transfer either of the
Railroad Leases without the prior written consent of Assignor, which consent may
be withheld in Assignor's sole and absolute discretion (or the lessor's express
release of Assignor from the Railroad Leases), provided that if a proposed
amendment of the Railroad Leases by Assignee does not increase the potential
liability of Assignor under the Railroad Leases, and does not create any
possibility of competition with Assignor's asphalt business, then Assignor will
not unreasonably withhold its consent to such amendment.

         4. COPIES TO ASSIGNOR. Assignee hereby agrees to promptly provide
Assignor with concurrent copies of all correspondence and notices sent or
received by Assignee regarding the Railroad Leases.

         5. ATTORNEYS' FEES. In the event of any litigation or proceeding
between the parties hereto for breach of or to enforce any provision or right
hereunder, the unsuccessful party in such action shall pay to the successful
party all costs and expenses, expressly including but not limited to, reasonable
attorneys' fees incurred by the successful party in connection with such action.
The successful party shall be that party who, in the light of the issues
litigated and the court's decisions on those issues, was more successful. The
party who was more successful need not be determined to be the party who
recovers a judgment. An action shall include proceedings in bankruptcy court.

         6. MISCELLANEOUS. This Agreement shall be binding upon and inure to the
benefit of each of the parties hereto and to their respective successors and
assigns. This Agreement may be executed in any number of counterparts, each of
which shall be deemed an original, and all of which when taken together shall
constitute but one and the same agreement.


                                       2
<PAGE>   28


This Agreement shall be governed by and construed in accordance with the laws of
the State of California. If any provision of this Agreement shall be invalid or
prohibited thereunder, such provision shall be effective to the extent of such
prohibition without invalidating the remainder of such provision or the
remaining provisions of this Agreement which shall remain fully binding and in
full force and effect. The headings of the paragraphs of this Agreement are
inserted solely for convenience of reference and are not a part of, and are not
intended to govern, limit or aid in the construction of, any term or provision
hereof.

         IN WITNESS WHEREOF, Assignor and Assignee have executed this Agreement
on the date first above written.


                                         "ASSIGNOR"

                                         CALMAT CO., a Delaware corporation

                                         By:
                                            ------------------------------------
                                            Title:
                                                  ------------------------------


                                         "ASSIGNEE"


                                         ---------------------------------------

                                         By:
                                            ------------------------------------
                                            Title:
                                                  ------------------------------


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