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                                                                   EXHIBIT 10.20

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR
APPLICABLE STATE SECURITIES LAWS AND MAY NOT BE TRANSFERRED, SOLD OR OTHERWISE
DISPOSED OF IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT WITH RESPECT
TO THE SECURITY, FILED AND MADE EFFECTIVE UNDER THE SECURITIES ACT OF 1933 AND
SUCH APPLICABLE STATE SECURITIES LAWS, OR UNLESS THE ISSUER RECEIVES AN OPINION
OF COUNSEL SATISFACTORY TO THE ISSUER TO THE EFFECT THAT REGISTRATION UNDER SUCH
ACT AND SUCH APPLICABLE STATE SECURITIES LAWS IS NOT REQUIRED.

                          SUBORDINATED PROMISSORY NOTE

DATE: JULY 13, 2001                                                     $136,421

                             OAKHURST COMPANY, INC.

OAKHURST COMPANY, INC., a Delaware corporation (together with its successors and
assigns the "Issuer") for value received hereby promises to pay to MAARTEN D.
HEMSLEY, an individual residing in the Commonwealth of Massachusetts, or order,
(the "Noteholder") by wire transfer of immediately available funds to an account
designated by the Noteholder by notice to the Issuer the principal sum of One
Hundred Twenty-Six Thousand Seven Hundred Twenty-Nine ($136,421) together with
interest on the unpaid principal balance of this Note from time to time
outstanding at the rate of twelve percent (12%) per year, compounded annually.
All payments of principal and interest shall be made in such coin or currency of
the United States of America as at the time of payment shall be legal tender for
the payment of public and private debts.

1.   DEFINITIONS. The following terms for all purposes of this Note shall have
     the meanings specified below. All accounting terms used herein and not
     expressly defined shall have the meanings given to them in accordance with
     generally accepted accounting principles as in effect from time to time.
     The terms defined in this Section 1 include the plural as well as the
     singular.

     (a)  "Acceleration Notice" shall have the meaning set forth in Section 3.

     (b)  "Affiliate" means with respect to any Person any other Person directly
          or indirectly controlling, controlled by or under common control with,
          such Person.

     (c)  "Business Day" means any day except a Saturday, Sunday or other day on
          which commercial banks in the State of Delaware are authorized by law
          to close.

     (d)  "Debt" means at any date an amount equal to or greater than $100,000
          of (i) all obligations of the Issuer for borrowed money; (ii) all
          obligations of the Issuer evidenced by bonds, debentures, notes, or
          other similar instruments; (iii) all obligations of the Issuer in
          respect of letters of credit or other similar instruments (or
          reimbursement obligations with respect thereto;) (iv) all obligations
          of the Issuer to pay the deferred purchase price of property or
          services, except trade payables; (v) all obligations of the Issuer as
          lessee under capitalized leases; (vi) all Debt of others secured by a
          Lien on any asset of the Issuer, whether or not such Debt is assumed
          by such Person; and (vii) any guarantee by the Issuer of the payment
          obligation of another Person.

     (e)  "Default" means any condition or event which constitutes an Event of
          Default or which with the giving of notice or lapse of time or both
          would, unless cured or waived, become an Event of Default.

     (f)  Event of Default" shall have the meaning set forth in Section 3.

     (g)  "Lien" means, with respect to any asset, any mortgage, lien, pledge,
          charge, security interest or encumbrance of any kind in respect of
          such asset. For the purposes of this Note, the Issuer shall be deemed
          to own subject to a Lien any asset which it has acquired or holds
          subject to the interest of a vendor or lessor under any conditional
          sale agreement, capitalized lease or other title retention agreement
          relating to such asset.

     (h)  "Maturity Date" shall mean 5:00 p.m. Eastern Time on July 3, 2005.

     (i)  "Notice of Default" shall have the meaning set forth in Section 3.

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     (j)  "Person" means any individual, corporation, partnership, firm,
          association, joint venture, joint stock company, trust, unincorporated
          organization or other entity, or any government or regulatory,
          administrative or political subdivision or agency, department or
          instrumentality thereof.

     (k)  "Senior Indebtedness" means indebtedness to any bank or other lending
          institution, including, but not limited to (i) all currently
          outstanding indebtedness of the Issuer to Finova Capital Corporation
          (the "Senior Lender,") as the same may be amended, modified, increased
          or decreased from time to time, by agreement between the Senior Lender
          and the Issuer; (ii) any and all replacements or refinancings of the
          indebtedness to the Senior Lender with one or more other lending
          entities, whether any such refinancing is for a greater or lesser
          amount than the current indebtedness to the Senior Lender; (iii) all
          obligations of the Issuer to Comerica Bank-Texas ("Comerica") under
          the guaranty by the Issuer of the obligations of Sterling Construction
          Company, a Michigan corporation, to Comerica (the "Comerica
          Obligations;") and (iv) any and all replacements or refinancings of
          the Comerica Obligations (whether any such replacement or refinancing
          is for a greater or lesser amount than the amount replaced or
          refinanced) with one or more other lending institutions that is
          guaranteed by, or is the direct obligation of, the Issuer.

     (l)  "Subordinated Note" shall have the meaning set forth in Section 7.

     (m)  The "Transaction Agreement" shall have the meaning set forth in
          Section 3(b).

2.   PAYMENT OF PRINCIPAL AND INTEREST.

     (a)  Additional Definitions. The following additional terms shall have the
          following meanings:

          (i)   The "Davies First Note" shall mean the Issuer's Secured
                Promissory Note dated October 18, 1999, as amended, issued to
                Robert M. Davies and in which Maarten D. Hemsley has a
                participatory interest.

          (ii)  The "Davies Second Note" shall mean that certain promissory note
                of even date herewith issued to Robert M. Davies and having
                substantially the same terms and conditions as this Note.

          (iii) The "Manning Note" shall mean the secured promissory note of the
                Issuer issued to James D. Manning and dated October 29, 2001 in
                the original principal amount of $800,000 as the same is amended
                by that certain Amendment to Secured Promissory Note of the
                Issuer of even date herewith.

          (iv)  "Net Cash Flow" shall mean (i) the operating cash flow of Steel
                City Products, Inc. ("SCPI") and Sterling Construction Company,
                both subsidiaries of the Issuer, to the extent they are
                permitted by their bank or institutional lenders to dividend or
                otherwise transfer cash to the Issuer; plus (ii) the proceeds
                from the sale by the Issuer of any shares of its common stock
                after the date hereof; plus (iii) any proceeds received by the
                Issuer from the exercise of any stock options; less any or all
                of the foregoing amounts that the Issuer's Board of Directors in
                its sole and absolute discretion determines should be reserved
                for the payment of the Issuer's past, current and future
                overhead expenses.

          (v)   "Net Cash Proceeds" shall mean the net proceeds received by the
                Issuer from the sale of assets of SCPI (other than sales of
                SCPI's inventory and other sales made in the ordinary course of
                business;) less any or all of such proceeds that the Issuer's
                Board of Directors in its sole and absolute discretion
                determines should be reserved for the payment of the Issuer's
                past, present and future overhead expenses.

          (vi)  References in this Section 2 to payments being made "pro rata"
                shall mean in proportion to the total amount of accrued interest
                or principal (as the case may be) owed under the notes in
                question at the time the computation is made.

     (b)  Sources of Payment. The principal of, and accrued interest on, this
          Note shall be payable


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          prior to the Maturity Date to the extent of any Net Cash Flow and Net
          Cash Proceeds of the Issuer.

          (i)   Application of Net Cash Flow. To the extent that Net Cash Flow
                becomes available from time to time it shall be applied in the
                following manner and sequence:

                (A)  first, to pay pro rata accrued interest on the Manning Note
                     and the Davies First Note;

                (B)  second, to pay pro rata the remaining principal outstanding
                     on the Manning Note and the Davies First Note;

                (C)  third, upon payment in full of all accrued interest and
                     outstanding principal on the Manning Note and the Davies
                     First Note to pay pro rata accrued interest on this Note
                     and the Davies Second Note; and

                (D)  fourth, to pay pro rata the then outstanding principal of
                     this Note and the Davies Second Note.

          (ii)  Application of Net Cash Proceeds. Any Net Cash Proceeds that
                become available shall be applied in the following manner:

                (A)  first, to pay pro rata any accrued interest on the Manning
                     Note and the Davies First Note;

                (B)  second, equal amounts of remaining Net Cash Proceeds shall
                     be applied to the repayment of the Manning Note and the
                     Davies First Note until all accrued interest and
                     outstanding principal on the Manning Note and the Davies
                     First Note have been paid in full;

                (C)  third, to repay any remaining outstanding principal balance
                     of the Manning Note;

                (D)  fourth, upon payment in full of all accrued interest and
                     outstanding principal on the Manning Note and the Davies
                     First Note to pay pro rata accrued interest on this Note
                     and the Davies Second Note; and

                (E)  fifth, to repay pro rata the principal outstanding on this
                     Note and the Davies Second Note.

     (c)  Extension of Maturity Date. To the extent that all accrued interest
          and the outstanding principal of this Note have not been paid on or
          before the Maturity date, the Issuer may request an extension of the
          Maturity Date until sufficient Net Cash Flow and/or Net Cash Proceeds
          are available to do so, but Maarten D. Hemsley shall have no
          obligation to grant such an extension.

     (d)  Compounding of Interest. Accrued but unpaid interest will be added to
          the principal balance hereof annually.

     (e)  No Impairment of Payment Obligation. No provision of this Note shall
          alter or impair the obligations of the Issuer to pay the principal of,
          or interest on, this Note at the place and time, and in the currency,
          herein prescribed.

     (f)  Prepayment. The principal hereunder shall be subject to prepayment by
          the Issuer at any time without the consent of the Noteholder and
          without premium or penalty, subject to any restriction on prepayment
          required by Comerica.

3.   EVENTS OF DEFAULT AND REMEDIES. In case one or more of the following events
     ("Events of Default") shall have occurred and be continuing:

     (a)  default in the payment of the principal of or interest on this Note as
          and when the same shall become due and payable; or

     (b)  failure on the part of the Issuer duly to observe or perform (i) any
          other of the covenants or agreements on the part of the Issuer
          contained herein (other than those covered by clause (a),


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          above;) or (ii) any material covenants or agreements on the part of
          the Issuer contained in any other agreement between the Issuer and the
          Noteholder, including, but not limited to, that certain Transaction
          Agreement of even date herewith (the "Transaction Agreement,") in
          either such case for a period of 30 days after the date on which
          written notice specifying such failure, stating that such notice is a
          "Notice of Default" hereunder and demanding that the Issuer remedy the
          same, shall have been given by registered or certified mail, return
          receipt requested, to the Issuer; or

     (c)  the prepayment of any Subordinated Note in violation of the provisions
          of Section 7 of this Note; or

     (d)  any event or condition shall occur which results in the acceleration
          of the maturity of any Debt or enables or, with the giving of notice
          or lapse of time or both, would enable the holder of such Debt or any
          Person acting on such holder's behalf to accelerate the maturity
          thereof; or

     (e)  the Issuer pursuant to, or within the meaning of, any bankruptcy or
          insolvency law: (i) commences a voluntary case or proceeding; (ii)
          consents to the entry of an order for relief against it in an
          involuntary case or proceeding; (iii) consents to the appointment of a
          receiver or custodian of it or for all or substantially all of its
          property; (iv) makes a general assignment for the benefit of its
          creditors; or (v) admits in writing its inability to pay its debts as
          the same become due,

     then in each case where an Event of Default specified in Section 3(a)
     through 3(d) occurs, the Holder, by notice in writing to the Issuer (the
     "Acceleration Notice") may declare the principal hereunder to be due and
     payable immediately, and upon any such declaration the same shall become
     immediately due and payable; provided however, that if an Event of Default
     specified in Section 3(e) occurs, the principal hereunder shall become and
     be immediately due and payable without any declaration or other act on the
     part of the Holder.

4.   REIMBURSEMENT OF EXPENSES. The Issuer shall reimburse the Noteholder, on
     demand, for any and all costs and expenses, including reasonable attorneys'
     fees and court costs, incurred by the Noteholder in collecting or otherwise
     enforcing this Note or in attempting to do any of the foregoing.

5.   POWERS AND REMEDIES CUMULATIVE; DELAY OR OMISSION NOT A WAIVER OF DEFAULT.

     (a)  No right or remedy herein conferred upon or reserved to the Holder is
          intended to be exclusive of any other right or remedy, and every right
          and remedy shall, to the extent permitted by law, be cumulative and in
          addition to every other right and remedy given hereunder or now or
          hereafter existing at law or in equity or otherwise. The assertion or
          employment of any right or remedy hereunder, or otherwise, shall not
          prevent the concurrent assertion or employment of any other
          appropriate right or remedy.

     (b)  No delay or omission of the Holder to exercise any right or power
          accruing upon any Default or Event of Default occurring and continuing
          as aforesaid shall impair any such right or power or shall be
          construed to be a waiver of any such Default or Event of Default or an
          acquiescence therein; and every power and remedy given by this Note or
          by law may be exercised from time to time, and as often as shall be
          deemed expedient, by the Holder.


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6.   WAIVER OF PAST DEFAULTS.

     (a)  The Noteholder may waive any past Default or Event of Default
          hereunder and its consequences. In the case of any such waiver, the
          Issuer and the Noteholder shall be restored to their former positions
          and rights hereunder, respectively; but no such waiver shall extend to
          any subsequent or other Default or impair any right consequent
          thereon.

     (b)  Upon any such waiver, such Default shall cease to exist and be deemed
          to have been cured and not to have occurred, and any Default or Event
          of Default arising therefrom shall be deemed to have been cured, and
          not to have occurred for every purpose of the Notes; but no such
          waiver shall extend to any subsequent or other default or Event of
          Default or impair any right consequent thereon.

7.   SUBORDINATION.

     (a)  No payment on account of principal of, or interest on, (i) that
          certain promissory note dated July 3, 2001 in the original principal
          amount of $1,000,000 issued to KTI, Inc.; (ii) the Davies First Note;
          (iv) the Manning Note; (iii) this Note; or (iv) any other promissory
          note issued contemporaneously herewith pursuant to the Transaction
          Agreement (each a "Subordinated Note and collectively, the
          "Subordinated Notes") shall be made, and no Subordinated Notes shall
          be redeemed or purchased directly or indirectly by the Issuer (or any
          of its subsidiaries), if at the time of such payment or purchase or
          immediately after giving effect thereto, (i) there shall exist a
          default in any payment with respect to the Senior Indebtedness or (ii)
          there shall have occurred an event of default as those terms may be
          defined in the instrument under which the same is outstanding (other
          than a default in the payment of amounts due thereon) with respect to
          the Senior Indebtedness, permitting the holders thereof to accelerate
          the maturity thereof, and such event of default shall not have been
          cured or waived or shall not have ceased to exist.

     (b)  Subject to payment in full of the Senior Indebtedness, the holders of
          the Subordinated Notes shall be subrogated to the rights of the
          holders of Senior Indebtedness to receive payments or distributions of
          the assets of the Issuer made on such Senior Indebtedness until all
          principal and interest on the Subordinated Notes shall be paid in
          full; and for purposes of such subrogation, no payments or
          distributions to the holders of Senior Indebtedness of any cash,
          property or securities to which any holders of the Subordinated Notes
          would be entitled except for the subordination provisions of this
          Section 6 shall, as between the holders of the Subordinated Notes and
          the Issuer and/or its creditors other than the holders of the Senior
          Indebtedness, be deemed to be a payment on account of the Senior
          Indebtedness.

     (c)  The provisions of this Section 7 are and are intended solely for the
          purposes of defining the relative rights of the holders of the
          Subordinated Notes and the holders of Senior Indebtedness and nothing
          in this Section 7 shall impair, as between the Issuer and any holders
          of the Subordinated Notes, the obligation of the Issuer, which is
          unconditional and absolute, to pay to the holders of the Subordinated
          Notes the principal thereof and interest thereon, in accordance with
          the terms of the Subordinated Notes, nor shall anything herein prevent
          any holders of the Subordinated Notes from exercising all remedies
          otherwise permitted by applicable law or hereunder upon default,
          subject to the rights set forth above of holders of Senior
          Indebtedness to receive cash, property or securities otherwise payable
          or deliverable to the holders of the Subordinated Notes.

     (d)  Upon any payment (including by redemption) which is not a payment in
          full of all of the principal amount and accrued interest of all
          outstanding Subordinated Notes, the aggregate amount of the payments
          shall be allocated to all the Subordinated Notes then outstanding in
          proportion to the amounts of principal and interest due thereunder, so
          that the amount of principal and interest paid under this Note shall
          bear the same ratio to the aggregate principal and accrued interest
          paid under all of the Subordinated Notes as the then outstanding


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          principal and accrued interest then owed under this Note bears to the
          aggregate principal and accrued interest then owed under all
          Subordinated Notes then outstanding.

8.   MODIFICATION OF NOTE. This Note may be modified only with the written
     consent of the Noteholder and the Issuer, provided, however, that no
     modification of Section 2 shall be made that would adversely affect the
     payment by the Issuer of the principal of, or the interest on, the Manning
     Note, the Davies First Note or the Davies Second Note, or that would result
     in either or both of the principal of and interest on this Note being paid
     sooner or in a greater amount than is provided for under Section 2, above.
     To this extent, the holders of the Manning Note, the Davies First Note and
     the Davies Second Note shall be deemed beneficiaries of Section 2 of this
     Note.

9.   MISCELLANEOUS. This Note shall be governed by and be construed in
     accordance with the laws of the State of Delaware without regard to the
     conflicts of law rules of such state. The Issuer hereby waives presentment,
     demand, notice, protest and all other demands and notices in connection
     with the delivery, acceptance, performance and enforcement of this Note,
     except as specifically provided herein, and assents to extensions of the
     time of payment, or forbearance or other indulgence without notice. The
     section headings herein are for convenience only and shall not affect the
     construction hereof.

     THE ISSUER AND THE NOTEHOLDER HEREBY IRREVOCABLY WAIVE ALL RIGHT TO TRIAL
     BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM ARISING OUT OF OR
     RELATING TO THIS NOTE.

10.  SUBMISSION TO JURISDICTION. The Issuer irrevocably submits to the exclusive
     jurisdiction of the state and federal courts located in the State of
     Delaware for the purposes of any suit, action or other proceeding arising
     out of this Note. The Issuer further agrees that service of any process,
     summons, notice or document by U.S. registered mail to the Issuer address
     set forth below shall be effective service of process for any action, suit
     or proceeding in the State of Delaware with respect to any matters to which
     it has submitted to jurisdiction in this paragraph. The Issuer irrevocably
     and unconditionally waives any objection to the laying of venue of any
     action, suit or proceeding arising out of this Note in the foregoing
     courts, and hereby and thereby further irrevocably and unconditionally
     waives and agrees not to plead or claim in any such court that any such
     action, suit or proceeding brought in any such court has been brought in an
     inconvenient forum.

IN WITNESS WHEREOF, the Issuer has caused this instrument to be duly executed as
of the date first set forth above.


OAKHURST COMPANY, INC.
2751 Centerville Road -- Suite 3131
Wilmington, Delaware 19803


By:            /s/ Roger M. Barzun
    ---------------------------------------
    Roger M. Barzun, Senior Vice President



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