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                                                                   EXHIBIT 10.43

                     AMENDED AND RESTATED SECURITY AGREEMENT

         THIS AMENDED AND RESTATED SECURITY AGREEMENT, dated as of April 28,
2000 (as amended and modified from time to time, this "Agreement"), by and among
the Persons identified as "Grantors" on the signature pages hereto and such
other Persons as may become Grantors after the date hereof (the "Grantors") and
BANK OF AMERICA, N.A., as collateral agent (in such capacity, the "Collateral
Agent") for the lenders from time to time party to the Credit Agreement
described below and certain Affiliates of such lenders identified herein (the
"Lenders"), amends and restates that certain Amended and Restated Security
Agreement dated as of August 5, 1999 by and among the parties hereto.

                                   WITNESSETH

         WHEREAS, a $105 million revolving credit facility (the "Existing Credit
Facility") was established in favor of RailWorks Corporation, a Delaware
corporation (the "Borrower"), pursuant to the terms of that Amended and Restated
Credit Agreement dated as of August 5, 1999 (as amended and modified, the
"Existing Credit Agreement") among the Borrower, the Subsidiaries of the
Borrower identified therein, the lenders identified therein, First Union
National Bank, as Documentation Agent, Bank of America Canada, as Canadian
Administrative Agent, and Bank of America, N.A., as Domestic Administrative
Agent;

         WHEREAS, pursuant to that Amended and Restated Credit Agreement dated
as of the date hereof (as amended and modified from time to time, the "Credit
Agreement") among the Borrower, certain Subsidiaries of the Borrower identified
therein, the lenders identified therein, First Union National Bank, as
Documentation Agent, and Bank of America, N.A., as Administrative Agent, the
Lenders have agreed to provide an amended and restated credit facility to
replace, refinance and increase the Existing Credit Facility;

         WHEREAS, it is a condition precedent to the effectiveness of the Credit
Agreement and the obligations of the Lenders to make their respective loans and
extensions of credit to the Borrower under the Credit Agreement that the
Grantors shall have executed and delivered this Agreement to the Collateral
Agent for the ratable benefit of the Lenders;

         NOW, THEREFORE, in consideration of the premises and to induce the
Agents and the Lenders to enter into the Credit Agreement and to induce the
Lenders to make their respective loans and extensions of credit thereunder, the
Grantors hereby agree with the Collateral Agent, for the ratable benefit of the
Lenders, as follows:

         SECTION 12.  Defined Terms.

         12.1     Definitions.

                  (a)      Unless otherwise defined herein, terms defined in the
         Credit Agreement and used herein shall have the meanings provided in
         the Credit Agreement, and the following terms which are defined in the
         Uniform Commercial Code in effect in the State of New York on the date
         hereof are used herein as so defined: Accounts, Chattel Paper, Deposit
         Accounts, Documents, Equipment, Farm Products, Fixtures, General
         Intangibles, Instruments, Inventory, Investment Property, Minerals and
         Proceeds. For purposes of this Agreement, the term "Lender" shall
         include any affiliate of any Lender which has entered into a Hedging
         Agreement with any Grantor to the extent permitted by the Credit
         Agreement.

                  (b)      The following terms shall have the following
         meanings:

                  "Collateral":  as defined in Section 2 of this Agreement.

                  "Collateral Account": any collateral account established by
         the Collateral Agent as provided in Section 3.3 hereof or Section 6.2
         hereof.

                  "Copyright License": any written agreement, naming any Grantor
         as licensor, granting any right under any Copyright including, without
         limitation, any thereof referred to in Schedule 3 hereto.


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                  "Copyrights": (a) all registered United States copyrights in
         all Works, now existing or hereafter created or acquired, all
         registrations and recordings thereof, and all applications in
         connection therewith, including, without limitation, registrations,
         recordings and applications in the United States Copyright office
         including, without limitation, any thereof referred to in Schedule 3
         hereto, and (b) all renewals thereof including, without limitation, any
         thereof referred to in Schedule 3 hereto.

                  "Patent License": any written agreement providing for the
         grant by or to a Grantor of any right to manufacture, use or sell any
         invention covered by a Patent, including, without limitation, any
         thereof referred to in Schedule 3 hereto.

                  "Patents": (a) all letters patent of the United States or any
         other country and all reissues and extensions thereof, including,
         without limitation, any letters patent referred to in Schedule 3
         hereto, and (b) all applications for letters patent of the United
         States or any other country and all divisions, continuations and
         continuations-in-part thereof, including, without limitation, any
         thereof referred to in Schedule 3 hereto.

                  "Secured Obligations": the collective reference to all of the
         obligations of the Grantors to the Lenders (including the Issuing
         Lender) and the Agents, whenever arising, under the Credit Agreement or
         any of the other Credit Documents (including, but not limited to, any
         interest accruing after the occurrence of a Bankruptcy Event with
         respect to any Grantor, regardless of whether such interest is an
         allowed claim under the Bankruptcy Code), howsoever evidenced, created,
         incurred or acquired, whether primary, secondary, direct, contingent,
         or joint and several, including, without limitation, all liabilities
         arising under Hedging Agreements relating to the Obligations to the
         extent permitted under the Credit Agreement, and all obligations and
         liabilities incurred in connection with collecting and enforcing the
         foregoing.

                  "Trademark License": any written agreement providing for the
         grant by or to a Grantor of any right to use any Trademark, including,
         without limitation, any thereof referred to in Schedule 3 hereto.

                  "Trademarks": (a) all trademarks, trade names, corporate
         names, company names, business names, fictitious business names, trade
         styles, service marks, logos and other source or business identifiers,
         and the goodwill associated therewith, now existing or hereafter
         adopted or acquired, all registrations and recordings thereof, and all
         applications in connection therewith, whether in the United States
         Patent and Trademark Office or in any similar office or agency of the
         United States, any State thereof or any other country or any political
         subdivision thereof, or otherwise, including, without limitation, any
         thereof referred to in Schedule 3 hereto, and (b) all renewals thereof.

                  "Uniform Commercial Code": the Uniform Commercial Code as from
         time to time in effect in the State of New York.

                  "Work": any work which is subject to copyright protection
         pursuant to Title 17 of the United States Code.

         12.2     Other Definitional Provisions.

                  (a)      The words "hereof," "herein" and "hereunder" and

         words of similar import when used in this Agreement shall refer to this
         Agreement as a whole and not to any particular provision of this
         Agreement, and section and paragraph references are to this Agreement
         unless otherwise specified.

                  (b)      The meanings given to terms defined herein shall be
         equally applicable to both the singular and plural forms of such terms.

         SECTION 13. Grant of Security Interest. As collateral security for the
prompt and complete payment and performance when due (whether at the stated
maturity, by acceleration or otherwise) of the Secured Obligations, each of the
Grantors hereby grants to the Collateral Agent, for the ratable benefit of the
Lenders, a security interest in all of the following property now owned or at
any time hereafter acquired by such Grantor or in which such Grantor now has or
at any time in the future may acquire any right, title or interest
(collectively, the "Collateral"):

                  (a)      all Accounts;


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                  (b)      all cash and Cash Equivalents maintained on deposit
                  with the Collateral Agent;

                  (c)      all Chattel Paper;

                  (d)      all Copyrights;

                  (e)      all Copyright Licenses;

                  (f)      all Deposit Accounts;

                  (g)      all Documents;

                  (h)      all Equipment;

                  (i)      all Fixtures;

                  (j)      all General Intangibles;

                  (k)      all Instruments;

                  (l)      all Inventory;

                  (m)      all Investment Property;

                  (n)      all Patents;

                  (o)      all Patent Licenses;

                  (p)      all Trademarks;

                  (q)      all Trademark Licenses;

                  (r)      all books, records, ledger cards, files,
                  correspondence, computer programs, tapes, disks, and related
                  data processing software (owned by such Grantor or in which it
                  has an interest) that at any time evidence or contain
                  information relating to any Collateral or are otherwise
                  necessary or helpful in the collection thereof or realization
                  thereupon; and

                  (s)      to the extent not otherwise included, all Proceeds
                  and products of any and all of the foregoing.

         The Grantors and the Collateral Agent, on behalf of the Lenders, hereby
acknowledge and agree that the security interest created hereby in the
Collateral (i) constitutes continuing collateral security for all of the Secured
Obligations, whether now existing or hereafter arising, and (ii) is not to be
construed as an assignment of any Copyrights, Copyright Licenses, Patents,
Patent Licenses, Trademarks or Trademark Licenses. The Grantors and the
Collateral Agent, on behalf of the Lenders, hereby further agree that this
Agreement shall not constitute an assignment of, or a grant of security interest
in, any contract or other agreement to which any Grantor is a party if such
assignment or grant of a security interest is prohibited by the terms of such
contract or other agreement.

         SECTION 14.  Provisions Relating to Accounts.

         14.1     Grantors Remain Liable under Accounts. Anything herein to the
contrary notwithstanding, each of the Grantors shall remain liable under each of
its Accounts to observe and perform all the conditions and obligations to be
observed and performed by it thereunder, all in accordance with the terms of any
agreement giving rise to each such Account. Neither any Agent nor any Lender
shall have any obligation or liability under any Account (or any agreement
giving rise thereto) by reason of or arising out of this Agreement or the
receipt by any Agent or any Lender of any payment relating to such Account
pursuant hereto, nor shall any Agent or any Lender be obligated in any manner to
perform any of the obligations of a Grantor under or pursuant to any Account (or
any agreement giving rise thereto), to make any payment, to make any inquiry as
to the nature or the sufficiency of any


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payment received by it or as to the sufficiency of any performance by any party
under any Account (or any agreement giving rise thereto), to present or file any
claim, to take any action to enforce any performance or to collect the payment
of any amounts which may have been assigned to it or to which it may be entitled
at any time or times.

         14.2     Analysis of Accounts. The Collateral Agent shall have the
right, once during each calendar year or at any time after the occurrence and
during the continuation of an Event of Default, to make test verifications of
the Accounts in any manner and through any medium that it reasonably considers
advisable, and the Grantors shall furnish all such assistance and information as
the Collateral Agent may reasonably require in connection with such test
verifications. At any time and from time to time, upon the Collateral Agent's
request and at the expense of the Grantors, the Grantors shall cause independent
public accountants or others satisfactory to the Collateral Agent to furnish to
the Collateral Agent reports showing reconciliations, aging and test
verifications of, and trial balances for, the Accounts. After the occurrence and
during the continuation of an Event of Default, the Collateral Agent in its own
name or in the name of others may communicate with account debtors on the
Accounts to verify with them to the Collateral Agent's satisfaction the
existence, amount and terms of any Accounts.

         14.3     Collections on Accounts.

         (a)      The Collateral Agent hereby authorizes the Grantors to collect
the Accounts, provided that the Collateral Agent may terminate said authority at
any time after the occurrence and during the continuation of an Event of
Default. If required by the Collateral Agent at any time after the occurrence
and during the continuation of an Event of Default, any payments of Accounts,
when collected by the Grantors, (i) shall be forthwith (and, in any event,
within two (2) Business Days) deposited by the Grantors in a Collateral Account
maintained under the sole dominion and control of the Collateral Agent, subject
to withdrawal by the Collateral Agent for the account of the Lenders only as
provided in Section 6.3 hereof, and (ii) until so turned over, shall be held by
the Grantors in trust for the Collateral Agent and the Lenders, segregated from
other funds of the Grantors.

         (b)      Each such deposit of Proceeds of Accounts shall be accompanied
by a report identifying in reasonable detail the nature and source of the
payments included in the deposit.

         (c)      At the Collateral Agent's reasonable request after the
occurrence and during the continuation of an Event of Default, the applicable
Grantor shall deliver to the Collateral Agent copies of all material documents
in its possession or control (or as to which they have a right or ability to
get) evidencing, and relating to, the agreements and transactions which gave
rise to the Accounts.

         SECTION 15. Representations and Warranties. Each of the Grantors hereby
represents and warrants to the Collateral Agent and the Lenders that:

         15.1     Title; No Other Liens. Except for Permitted Liens, the Grantor
owns each item of the Collateral free and clear of any and all Liens or claims
of others. No security agreement, financing statement or other public notice
with respect to all or any part of the Collateral is on file or of record in any
public office, except such as have been filed in favor of the Collateral Agent,
for the ratable benefit of the Lenders, pursuant to this Agreement and except
such as have been filed in connection with Permitted Liens.

         15.2     Perfected First Priority Liens. The security interests granted
in the Collateral are prior to all other Liens on the Collateral in existence on
the date hereof except for Permitted Liens and are enforceable as such against
all creditors of and purchasers from the Grantor.

         15.3     Chief Executive Office. The Grantor's chief executive office
and chief place of business, and the place where it keeps its books and records,
is located at the address shown on Schedule 1 hereto.

         15.4     Inventory. Set forth on Schedule 2 hereto are locations,
including street address and state, where at least eighty percent (80%) of the
inventory of the Grantors is located. Other than any Grantor which engages in
wood treatment, no Grantor holds any Inventory pursuant to consignment, sale or
return, sale on approval or similar arrangement.

         15.5     Ownership. Each Grantor is the legal and beneficial owner of
its Collateral and has the right to pledge, sell, assign or transfer the same.


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         15.6     Farm Products. None of the Collateral constitutes or is the
Proceeds of Farm Products.

         15.7     Minerals. None of the Collateral constitutes or is the
Proceeds of Minerals.

         15.8     Copyrights, Patents and Trademarks.

         (a)      Schedule 3 hereto includes all Copyrights, Copyright Licenses,
Patents, Patent Licenses, Trademarks and Trademark Licenses owned by the Grantor
in its own name.

         (b)      To the best of the Grantor's knowledge, each material
Copyright, Patent and Trademark of the Grantor is valid, subsisting, unexpired,
enforceable and has not been abandoned.

         (c)      No Copyright, Patent or Trademark of the Grantor is the
subject of any licensing or franchise agreement.

         (d)      No holding, decision or judgment has been rendered by any
Governmental Authority which would limit, cancel or question the validity of any
material Copyright, Patent or Trademark of the Grantor.

         (e)      No action or proceeding is pending seeking to limit, cancel or
question the validity of any material Copyright, Patent or Trademark of the
Grantor. No action or proceeding is pending which, if adversely determined,
would have a material adverse effect on the value of any material Copyright,
Patent or Trademark of the Grantor.

         SECTION 16. Covenants. Each of the Grantors covenants and agrees with
the Collateral Agent and the Lenders that, from and after the date of this
Agreement until the Secured Obligations have been paid in full and the
Commitments have been terminated:

         16.1     Maintenance of Perfected Security Interest; Further
Documentation.

         (a)      The Grantor shall maintain the security interest created by
this Agreement as a perfected security interest subject only to Permitted Liens
and shall defend such security interest against claims and demands of all
Persons, other than Permitted Liens.

         (b)      At any time and from time to time, upon the written request of
the Collateral Agent, and at the sole expense of the Grantor, the Grantor will
promptly and duly execute and deliver such further instruments and documents and
take such further action (including, without limitation all actions required
under the Federal Assignment of Claims Act or any similar state statute, filings
in respect of Copyrights with the United States Copyright Office and filings in
respect of Trademarks and Patents with the United States Patent and Trademark
Office) as the Collateral Agent may reasonably request for the purpose of
obtaining or preserving the full benefits of this Agreement and of the rights
and powers herein granted, including, without limitation, the filing of any
financing statements under the Uniform Commercial Code in effect in any
jurisdiction with respect to the security interests created hereby.

         16.2     Changes in Locations, Name, etc. The Grantor will not:

         (a)      change the location of its chief executive office and chief
place of business or the location at which it maintains its books and records
from that specified on Schedule 1 hereto, unless it shall have given the
Collateral Agent at least fifteen (15) days' prior written notice of such change
and any filings required under the Uniform Commercial Code in effect in the
affected jurisdiction to maintain the perfected security interest granted
pursuant to this Agreement shall have been made; or

         (b)      change its name, identity or corporate structure to such an
extent that any financing statement filed by the Collateral Agent in connection
with this Agreement would become seriously misleading, unless (i) it shall have
given the Collateral Agent at least fifteen (15) days' prior written notice of
such change and (ii) any filings required under the Uniform Commercial Code in
effect in the affected jurisdiction to maintain the perfected security interest
granted pursuant to this Agreement shall have been made.


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         (c)      if at any time at least eighty percent (80%) of the inventory
of the Grantors is not located at the locations set forth on Schedule 2, then
the Borrower shall promptly provide to the Collateral Agent a written update to
Schedule 2 such that such schedule, as updated, identifies locations at which at
least eighty percent (80%) of the inventory of the Grantors is located.

         (d)      upon the request of the Collateral Agent, the Borrower shall,
within ten (10) Business Days of such request, provide to the Collateral Agent a
written schedule of the locations, including street address and state, where any
of the Collateral is located.

         16.3     Further Identification of Collateral. The Grantor will furnish
to the Collateral Agent and the Lenders from time to time statements and
schedules further identifying and describing the Collateral and such other
reports in connection with the Collateral as the Collateral Agent may reasonably
request, all in reasonable detail.

         16.4     Delivery of Instruments/Chattel Paper. If any amount payable
under or in connection with any of the Collateral shall be or become evidenced
by any Instrument or Chattel Paper, the Grantor shall immediately deliver such
Instrument or Chattel Paper to the Collateral Agent, duly endorsed in a manner
satisfactory to the Collateral Agent, to be held as Collateral pursuant to this
Agreement.

         16.5     Preservation of Collateral. The Grantor shall keep the
Collateral in good order, condition and repair and not use the Collateral in
violation of the provisions of this Agreement or any other agreement relating to
the Collateral or any policy insuring the Collateral or any applicable statute,
law, bylaw, rule, regulation or ordinance.

         16.6     Indemnification. The Grantor agrees to pay, and to save the
Agents and the Lenders harmless from, any and all liabilities, costs and
expenses (including, without limitation, reasonable legal fees and expenses) (i)
with respect to, or resulting from any delay in paying, any and all excise,
sales or other taxes which may be payable or determined to be payable with
respect to any of the Collateral, (ii) with respect to, or resulting from, any
delay in complying with any Requirement of Law applicable to any of the
Collateral and (iii) in connection with any of the transactions contemplated by
this Agreement, except for any such liabilities which result from the gross
negligence or wilful misconduct of the Agents or the Lenders, respectively. In
any suit, proceeding or action brought by the Collateral Agent or any Lender
under any Account for any sum owing thereunder, the Grantor will save, indemnify
and keep the Collateral Agent and such Lender harmless from and against all
expense, loss or damage suffered by reason of any defense, setoff, counterclaim,
recoupment or reduction or liability whatsoever of the account debtor
thereunder, arising out of a breach by the Grantor of any obligation thereunder
or arising out of any other agreement, indebtedness or liability at any time
owing to or in favor of such account debtor or its successors from the Grantor.

         16.7     Covenants Relating to Accounts Upon Default. At any time after
the occurrence and during the continuation of an Event of Default:

                  (a)      the amount represented by the Grantor to the Lenders
         from time to time as owing by each account debtor or by all account
         debtors in respect of its Accounts will at such time be the correct
         amount in all material respects actually owing by such account debtor
         or debtors thereunder;

                  (b)      the Grantor will not amend, modify, terminate or
         waive any agreement giving rise to an Account in any manner which would
         reasonably be expected to materially adversely affect the value of the
         Accounts as Collateral;

                  (c)      the Grantor will not fail to exercise promptly and
         diligently each and every material right which it may have under each
         agreement giving rise to an Account (other than any right of
         termination);

                  (d)      the Grantor will not fail to deliver to the
         Collateral Agent a copy of each material demand, notice or document
         received by it relating in any way to any agreement giving rise to an
         Account; and

                  (e)      other than in the ordinary course of business as
generally conducted by the Grantor, the Grantor will not grant any extension of
the time of payment of any of the Accounts, compromise, compound or settle the
same for less than the full amount thereof, release, wholly or partially, any
Person liable for the payment thereof, or allow any credit or discount
whatsoever thereon.


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         16.8     Covenants Relating to Copyrights.

         (a)      The Grantor will employ the Copyright for each material Work
with such notice of copyright as may be required by law to secure copyright
protection.

         (b)      With respect to any material Copyright of the Grantor, the
Grantor (i) will not do any act or knowingly omit to do any act whereby such
Copyright may become invalidated, (ii) will not do any act, or omit to do any
act, whereby such Copyright may become injected into the public domain; (iii)
will notify the Collateral Agent immediately if it knows that such Copyright may
become injected into the public domain or of any adverse determination or
development (including, without limitation, the institution of, or any such
determination or development in, any court or tribunal in the United States or
any other country) regarding the Grantor's ownership of such Copyright or its
validity; (iii) will take all necessary steps as it shall deem appropriate under
the circumstances, to maintain and pursue each application (and to obtain the
relevant registration) and to maintain each registration of such Copyright
including, without limitation, filing of applications for renewal where
necessary; and (iv) will promptly notify the Collateral Agent of any material
infringement of such Copyright of which it becomes aware and will take such
actions as it shall reasonably deem appropriate under the circumstances to
protect such Copyright, including, where appropriate, the bringing of suit for
infringement, seeking injunctive relief and seeking to recover any and all
damages for such infringement.

         5.9      Covenants Relating to Patents and Trademarks.

         (a)      With respect to any material Trademark, the Grantor (either
itself or through licensees) will (i) continue to use such Trademark on each and
every trademark class of goods applicable to its current line as reflected in
its current catalogs, brochures and price lists in order to maintain such
Trademark in full force free from any claim of abandonment for non-use, (ii)
maintain as in the past the quality of products and services offered under such
Trademark, (iii) employ such Trademark with the appropriate notice of
registration, (iv) not adopt or use any mark which is confusingly similar or a
colorable imitation of such Trademark unless the Collateral Agent, for the
ratable benefit of the Lenders, shall obtain a perfected security interest in
such mark pursuant to this Agreement, and (v) not (and not permit any licensee
or sublicensee thereof to) do any act or knowingly omit to do any act whereby
such Trademark may become invalidated.

         (b)      With respect to any material Patent, the Grantor will not do
any act, or omit to do any act, whereby such Patent may become abandoned or
dedicated.

         (c)      The Grantor will notify the Collateral Agent and the Lenders
immediately if it knows, or has reason to know, that any application or
registration relating to any material Patent or material Trademark may become
abandoned or dedicated, or of any adverse determination or development
(including, without limitation, the institution of, or any such determination or
development in, any proceeding in the United States Patent and Trademark Office
or any court or tribunal in any country) regarding the Grantor's ownership of
any material Patent or material Trademark or its right to register the same or
to keep and maintain the same.

         (d)      The Grantor will take all reasonable and necessary steps,
including, without limitation, in any proceeding before the United States Patent
and Trademark Office, or any similar office or agency in any other country or
any political subdivision thereof, to maintain and pursue each application (and
to obtain the relevant registration) and to maintain each registration of its
material Patents and material Trademarks, including, without limitation, filing
of applications for renewal, affidavits of use and affidavits of
incontestability.

         (e)      In the event that any material Patent or material Trademark is
infringed, misappropriated or diluted by a third party, the Grantor shall
promptly report such event to the Collateral Agent and shall promptly take such
actions as the Grantor shall reasonably deem appropriate under the circumstances
to protect such Patent or Trademark, including, without limitation, where
appropriate, bringing of suit for infringement, misappropriation or dilution,
seeking injunctive relief and seeking to recover any and all damages for such
infringement, misappropriation or dilution.

         5.10     New Patents, Copyrights and Trademarks. The Grantor shall
promptly provide the Collateral Agent with (i) a listing of all applications, if
any, for new Copyrights, Patents or Trademarks (together with a listing of the
issuance of registrations or letters


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on present applications), which new applications and issued registrations or
letters shall be subject to the terms and conditions hereunder, and (ii) such
duly executed documents as the Collateral Agent may reasonably request to
evidence the security interest in the Copyright, Patent or Trademark which is
the subject of such new application.

         SECTION 17.  Remedies.

         17.1     Notice to Account Debtors. Upon the request of the Collateral
Agent at any time after the occurrence and during the continuation of an Event
of Default, the Grantors shall notify account debtors on the Accounts that the
Accounts have been assigned to the Collateral Agent for the ratable benefit of
the Lenders and that payments in respect thereof shall be made directly to the
Collateral Agent.

         17.2     Proceeds to be Turned Over To Collateral Agent. In addition to
the rights of the Collateral Agent and the Lenders specified in Section 3.3
hereof with respect to payments of Accounts, after the occurrence and during the
continuation of an Event of Default, all Proceeds received by the Grantors
consisting of cash and checks shall be held by the Grantors in trust for the
Collateral Agent and the Lenders, segregated from other funds of the Grantors,
and shall, forthwith upon receipt by the Grantors, be turned over to the
Collateral Agent in the exact form received by the Grantors (duly indorsed by
the Grantors to the Collateral Agent, if required) and held by the Collateral
Agent in a Collateral Account maintained under the sole dominion and control of
the Collateral Agent. All Proceeds, while held by the Collateral Agent in a
Collateral Account (or by the Grantors in trust for the Collateral Agent and the
Lenders), shall continue to be held as collateral security for all the Secured
Obligations and shall not constitute payment thereof until applied as provided
in Section 6.3 hereof.

         17.3     Application of Proceeds. At such intervals as may be agreed
upon by the Grantors and the Collateral Agent, or, at any time after an Event of
Default shall have occurred and be continuing, at the Collateral Agent's
election, the Collateral Agent may apply all or any part of Proceeds held in any
Collateral Account in payment of the Secured Obligations in the order set forth
in Section 3.15(c) of the Credit Agreement, and any part of such funds which the
Collateral Agent elects not so to apply and deems not required as collateral
security for the Secured Obligations shall be paid over from time to time by the
Collateral Agent to the Grantors or to whomsoever may be lawfully entitled to
receive the same. Any balance of such Proceeds remaining after the Secured
Obligations have been paid in full and the Commitments have been terminated
shall be paid over to the Grantors or to whomsoever may be lawfully entitled to
receive the same.

         17.4     Code Remedies. At any time after an Event of Default shall
have occurred and be continuing, the Collateral Agent, on behalf of the Lenders,
may exercise, in addition to all other rights and remedies granted to them in
this Agreement and in any other instrument or agreement securing, evidencing or
relating to the Secured Obligations, all rights and remedies of a secured party
under the Uniform Commercial Code. Without limiting the generality of the
foregoing, the Collateral Agent, without demand of performance or other demand,
presentment, protest, advertisement or notice of any kind (except any notice
required by law referred to below) to or upon the Grantors or any other Person
(all and each of which demands, defenses, advertisements and notices are hereby
waived), may in such circumstances forthwith collect, receive, appropriate and
realize upon the Collateral, or any part thereof, and/or may forthwith sell,
lease, assign, give option or options to purchase, or otherwise dispose of and
deliver the Collateral or any part thereof (or contract to do any of the
foregoing), in one or more parcels at public or private sale or sales, at any
exchange, broker's board or office of the Collateral Agent or any Lender or
elsewhere upon such terms and conditions as it may deem advisable and at such
prices as it may deem best, for cash or on credit or for future delivery without
assumption of any credit risk. The Collateral Agent or any Lender shall have the
right upon any such public sale or sales, and, to the extent permitted by law,
upon any such private sale or sales, to purchase the whole or any part of the
Collateral so sold, free of any right or equity of redemption in a Grantor,
which right or equity is hereby waived or released. The Grantors further agree,
at the Collateral Agent's request, to assemble the Collateral and make it
available to the Collateral Agent at places which the Collateral Agent shall
reasonably select, whether at the respective Grantor's premises or elsewhere.
The Collateral Agent shall apply the net proceeds of any such collection,
recovery, receipt, appropriation, realization or sale, after deducting all
reasonable costs and expenses of every kind incurred therein or incidental to
the care or safekeeping of any of the Collateral or in any way relating to the
Collateral or the rights of the Collateral Agent and the Lenders hereunder,
including, without limitation, reasonable and actual attorneys' fees and
disbursements, to the payment in whole or in part of the Secured Obligations, in
the order set forth in Section 3.15(c) of the Credit Agreement, and only after
such application and after the payment by the Collateral Agent of any other
amount required by any provision of law, including, without limitation, Section
9-504(1)(c) of the Uniform Commercial Code, need the Collateral Agent account
for the surplus, if any, to each of the Grantors. To the extent permitted by
applicable law, the Grantors


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<PAGE>   9

waive all claims, damages and demands it may acquire against the Collateral
Agent or any Lender arising out of the exercise by them of any rights hereunder.
If any notice of a proposed sale or other disposition of Collateral shall be
required by law, such notice shall be deemed reasonable and proper if received
by the Grantors at least twenty (20) days before such sale or other disposition.

         17.5     Deficiency. The Grantors shall remain liable for any
deficiency if the proceeds of any sale or other disposition of the Collateral
are insufficient to pay the Secured Obligations and the reasonable and actual
fees and disbursements of any attorneys employed by the Collateral Agent or any
Lender to collect such deficiency.

         SECTION 18.  Rights of Collateral Agent.

         18.1     Powers. Each of the Grantors hereby irrevocably constitutes
and appoints the Collateral Agent and any officer or agent thereof, with full
power of substitution, as its true and lawful attorney-in-fact with full
irrevocable power and authority in the place and stead of such Grantor and in
the name of such Grantor or in its own name, from time to time in the Collateral
Agent's reasonable discretion, for the purpose of carrying out the terms of this
Agreement, to take any and all appropriate action and to execute any and all
documents and instruments which may be necessary or desirable to secure the
Secured Obligations and grant security interests in the Collateral as
contemplated by this Agreement, and, without limiting the generality of the
foregoing, each Grantor hereby gives the Collateral Agent the power and right,
on behalf of such Grantor, without notice to or assent by such Grantor, at any
time after an Event of Default has occurred and is continuing, to do the
following:

                  (a)      in the name of such Grantor or its own name, or
         otherwise, to take possession of and indorse and collect any checks,
         drafts, notes, acceptances or other instruments for the payment of
         moneys due under any Account, Instrument or General Intangible or with
         respect to any other Collateral and to file any claim or to take any
         other action or proceeding in any court of law or equity or otherwise
         reasonably deemed appropriate by the Collateral Agent for the purpose
         of collecting any and all such moneys due under any Account, Instrument
         or General Intangible or with respect to any other Collateral, whenever
         payable; provided, however, that the Collateral Agent shall exercise
         the powers set forth in this clause (a) with respect to any Account
         only at any time when the authority of such Grantor to collect the
         Accounts has been terminated pursuant to Section 3.3(a) hereof;

                  (b)      to pay or discharge taxes and Liens levied or placed
         on or threatened against the Collateral, to effect, any repairs or any
         insurance called for by the terms all or any part of the premiums
         therefor and the costs thereof;

                  (c)      to execute, in connection with the sale provided for
         in Section 6.4 hereof, any endorsements, assignments or other
         instruments of conveyance or transfer with respect to the Collateral;
         and

                  (d)      (i) to direct any party liable for any payment under
         any of the Collateral to make payment of any and all moneys due or to
         become due thereunder directly to the Collateral Agent or as the
         Collateral Agent shall direct; (ii) to ask or demand for, collect,
         receive payment of and receipt for, any and all moneys, claims and
         other amounts due or to become due at any time in respect of or arising
         out of any Collateral; (iii) to sign and indorse any invoices, freight
         or express bills, bills of lading, storage or warehouse receipts,
         drafts against debtors, assignments, verifications, notices and other
         documents in connection with any of the Collateral; (iv) to commence
         and prosecute any suits, actions or proceedings at law or in equity in
         any court of competent jurisdiction to collect the Collateral or any
         thereof and to enforce any other right in respect of any Collateral;
         (v) to defend any suit, action or proceeding brought against such
         Grantor with respect to any Collateral; (vi) to settle, compromise or
         adjust any such suit, action or proceeding and, in connection
         therewith, to give such discharges or releases as the Collateral Agent
         may deem appropriate; (vii) to assign, or to grant licenses with
         respect to, any Copyright, Patent or Trademark (along with any goodwill
         relating thereto), on such terms and conditions as the Collateral Agent
         shall in its sole discretion determine, and (viii) generally, to sell,
         transfer, pledge and make any agreement with respect to or otherwise
         deal with any of the Collateral as fully and completely as though the
         Collateral Agent were the absolute owner thereof for all purposes, and
         to do, at the Collateral Agent's option and such Grantor's expense, at
         any time, or from time to time, all reasonable acts and things which
         the Collateral Agent deems necessary to protect, preserve or realize
         upon the Collateral and the Collateral Agent's security interests
         therein and to effect the intent of this Agreement, all as fully and
         effectively as such Grantor might do.


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<PAGE>   10

         The Collateral Agent agrees that, except after the occurrence and
during the continuance of an Event of Default, it will forbear from exercising
the power of attorney or any rights granted to the Collateral Agent pursuant to
this Section 7.1.

         18.2     Performance by Collateral Agent of Grantors' Obligations. If
any of the Grantors fail to perform or comply with any of their agreements
contained herein, the Collateral Agent, at its option, but without any
obligation to do so, may perform or comply, or otherwise cause performance or
compliance, with such agreement.

         18.3     Grantors' Reimbursement Obligation. The expenses of the
Collateral Agent incurred in connection with actions undertaken as provided in
this Section 7, together with interest thereon at the rate per annum set forth
in Section 3.1 of the Credit Agreement for Base Rate Loans from the date of
payment by the Collateral Agent to the date reimbursed by the Grantors, shall be
payable by the Grantors to the Collateral Agent on demand.

         18.4     Ratification; Power Coupled With An Interest. The Grantors
hereby ratify all that said attorneys shall lawfully do or cause to be done by
virtue hereof. All powers, authorizations and agencies contained in this
Agreement are coupled with an interest and are irrevocable until the Secured
Obligations have been paid in full and the Commitments have been terminated.

         SECTION 19. Duty of Collateral Agent. The Collateral Agent's sole duty
with respect to the custody, safekeeping and physical preservation of the
Collateral in its possession, under Section 9-207 of the Uniform Commercial Code
or otherwise, shall be to deal with it in the same manner as the Collateral
Agent deals with similar property for its own account. Neither the Collateral
Agent, any Lender nor any of their respective directors, officers, employees or
agents shall be liable for failure to demand, collect or realize upon any of the
Collateral or for any delay in doing so or shall be under any obligation to sell
or otherwise dispose of any Collateral upon the request of the Grantors or any
other Person or to take any other action whatsoever with regard to the
Collateral or any part thereof. The powers conferred on the Collateral Agent
hereunder are solely to protect the Collateral Agent's and the Lenders'
interests in the Collateral and shall not impose any duty upon the Collateral
Agent to exercise any such powers. The Collateral Agent and the Lenders shall be
accountable only for amounts that they actually receive as a result of the
exercise of such powers, and neither they nor any of their officers, directors,
employees or agents shall be responsible to the Grantors for any act or failure
to act hereunder, except for their own gross negligence or wilful misconduct.

         SECTION 20. Execution of Financing Statements. Pursuant to Section
9-402 of the Uniform Commercial Code, each of the Grantors authorizes the
Collateral Agent to file financing statements with respect to the Collateral
without the signature of such Grantor in such form and in such filing offices as
the Collateral Agent reasonably determines appropriate to perfect the security
interests of the Collateral Agent and the Lenders under this Agreement. A
carbon, photographic or other reproduction of this Agreement shall be sufficient
as a financing statement for filing in any jurisdiction.

         SECTION 21. Authority of Collateral Agent. The Grantors acknowledge
that the rights and responsibilities of the Collateral Agent under this
Agreement with respect to any action taken by the Collateral Agent or the
exercise or non-exercise by the Collateral Agent of any option, voting right
request, judgment or other right or remedy provided for herein or resulting or
arising out of this Agreement shall, as between the Collateral Agent and the
Lenders, be governed by the Credit Agreement and the other Credit Documents,
but, as between the Collateral Agent and the Grantors, the Collateral Agent
shall be conclusively presumed to be acting as agent for the Lenders with full
and valid authority so to act or refrain from acting, and the Grantors shall be
under no obligation, or entitlement, to make any inquiry respecting such
authority.

         SECTION 22. Notices. All notices shall be given or made in accordance
with Section 11.1 of the Credit Agreement.

         SECTION 23. Severability. Any provision of this Agreement which is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

         SECTION 24.  Amendments in Writing; No Waiver; Cumulative Remedies.


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<PAGE>   11

         24.1     Amendments in Writing. None of the terms or provisions of this
Agreement may be waived, amended, supplemented or otherwise modified except by a
written instrument executed by the Collateral Agent and the Grantors directly
affected thereby; provided that any provision of this Agreement may be waived by
the Collateral Agent in a letter or agreement executed by the Collateral Agent
or by facsimile transmission from the Collateral Agent.

         24.2     No Waiver by Course of Conduct. Neither the Collateral Agent
nor any Lender shall by any act (except by a written instrument pursuant to
Section 13.1 hereof), delay, indulgence, omission or otherwise be deemed to have
waived any right or remedy hereunder or to have acquiesced in any Default or
Event of Default or in any breach of any of the terms and conditions hereof. No
failure to exercise, nor any delay in exercising, on the part of the Collateral
Agent or any Lender, any right, power or privilege hereunder shall operate as a
waiver thereof. No single or partial exercise of any right, power or privilege
hereunder shall preclude any other or further exercise thereof or the exercise
of any other right, power or privilege. A waiver by the Collateral Agent or any
Lender of any right or remedy hereunder on any one occasion shall not be
construed as a bar to any right or remedy which the Collateral Agent or such
Lender would otherwise have on any future occasion.

         24.3     Remedies Cumulative. The rights and remedies herein provided
are cumulative, may be exercised singly or concurrently and are not exclusive of
any other rights or remedies provided by law.

         SECTION 25. Section Headings. The section and subsection headings used
in this Agreement are for convenience of reference only and are not to affect
the construction hereof or be taken into consideration in the interpretation
hereof.

         SECTION 26. Successors and Assigns. This Agreement shall be binding
upon the successors and assigns of the Grantors and shall inure to the benefit
of the Collateral Agent and the Lenders and their successors and assigns,
provided that the Grantors may not assign any of their rights or Secured
Obligations under this Agreement without the prior written consent of the
Collateral Agent and any such purported assignment without such consent shall be
null and void.

         SECTION  27. Term of Agreement. This Agreement and the Liens granted
hereunder shall remain in full force and effect until the Secured Obligations
have been paid in full and the Commitments have been terminated, at which time
the Collateral Agent shall release and terminate the Liens granted to it
hereunder. Upon such release and termination, (i) the Borrower shall be entitled
to the return, at its expense, of any and all funds in the Collateral Account
and such of the Collateral held by the Collateral Agent as shall not have been
sold or otherwise applied pursuant to the terms hereof and (ii) the Collateral
Agent will, at the Borrower's expense, execute and deliver to the Borrower such
UCC termination statements and other documents as the Borrower shall reasonably
request to evidence such termination.

         SECTION 28. Counterparts. This Agreement may be executed in any number
of counterparts, each of which where so executed and delivered shall be an
original, but all of which shall constitute one and the same instrument. It
shall not be necessary in making proof of this Agreement to produce or account
for more than one such counterpart.

         SECTION 29. GOVERNING LAW. THIS AGREEMENT AND THE RIGHTS AND SECURED
OBLIGATIONS OF THE PARTIES HEREUNDER SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

                  [Remainder of Page Intentionally Left Blank]


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<PAGE>   12



         IN WITNESS WHEREOF, the undersigned has caused this Agreement to be
duly executed and delivered as of the date first above written.

GRANTORS:               RAILWORKS CORPORATION,
                        a Delaware corporation
                        ALPHA-KEYSTONE ENGINEERING, INC.,
                        a Pennsylvania corporation
                        ANNEX RAILROAD BUILDERS, INC.,
                        an Indiana corporation
                        BIRMINGHAM WOOD, INC.,
                        an Alabama corporation
                        COMSTOCK HOLDINGS INC.,
                        a Delaware corporation
                        COMTRAK CONSTRUCTION, INC.,
                        a Georgia corporation
                        CONDON BROTHERS, INC.,
                        a Washington corporation
                        CPI CONCRETE PRODUCTS, INCORPORATED,
                        a Tennessee corporation
                        EARL CAMPBELL CONSTRUCTION COMPANY, INC.,
                        a Texas corporation FCM RAIL, LTD.,
                        a Michigan corporation
                        GANTREX CORPORATION,
                        a Pennsylvania corporation
                        H.P. MCGINLEY, INC.,
                        a Pennsylvania corporation
                        IMPULSE ELECTRIC ENTERPRISES OF NEW YORK, INC.,
                        a New York corporation
                        KENNEDY RAILROAD BUILDERS, INC.,
                        a Pennsylvania corporation
                        L.K. COMSTOCK & COMPANY, INC.,
                        a New York corporation
                        M-TRACK ENTERPRISES, INC.,
                        a New York corporation

                        By:
                           ---------------------------------------------
                        Name:   Michael R. Azarela
                        Title:  Executive Vice President of each of the
                                foregoing Guarantors

                           [Signature Pages Continue]


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<PAGE>   13


                         MCCORD TREATED WOOD, INC.,
                         an Alabama corporation
                         MERIT RAILROAD CONTRACTORS, INC.,
                         a Missouri corporation
                         MIDWEST CONSTRUCTION SERVICES, INC. ,
                         an Indiana corporation
                         MIDWEST RAILROAD CONSTRUCTION & MAINTENANCE
                         CORPORATION OF WYOMING, a Wyoming corporation
                         MINNESOTA RAILROAD SERVICE, INC.,
                         a Tennessee corporation
                         NEOSHO ASIA, INC.,
                         a Kansas corporation
                         NEOSHO CENTRAL AMERICA, INC.,
                         a Kansas corporation
                         NEOSHO CONSTRUCTION COMPANY, INCORPORATED,
                         a Kansas corporation
                         NEOSHO CONTRACTORS, INC.,
                         a Wyoming corporation
                         NEOSHO INCORPORATED,
                         a Kansas corporation
                         NEOSHO INTERNATIONAL, INC.,
                         a Kansas corporation
                         NEW ENGLAND RAILROAD CONSTRUCTION CO., INC.,
                         a Connecticut corporation
                         NORTHERN RAIL SERVICE AND SUPPLY COMPANY, INC.,
                         a Michigan corporation
                         RAILCORP, INC.,
                         an Ohio corporation
                         RAILROAD SERVICE, INC.,
                         a Nevada corporation
                         RAILWORKS RAIL SERVICES, INC.,
                         a Kansas corporation
                         RWKS TRANSIT, INC.,
                         a New York corporation
                         SHELDON ELECTRIC, INC.,
                         a Delaware corporation
                         SOUTHERN INDIANA WOOD PRESERVING CO., INC.,
                         an Indiana corporation
                         TWIGG CORPORATION,
                         a Maryland corporation

                         By:
                            --------------------------------------
                         Name:   Michael R. Azarela
                         Title:  Executive Vice President of each of the
                                 foregoing Guarantors

                           [Signature Pages Continue]


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<PAGE>   14


                            U.S. RAILWAY SUPPLY, INC.,
                            an Indiana corporation
                            U.S. TRACKWORKS, INC.,
                            a Michigan corporation
                            V&R ELECTRICAL CONTRACTORS, INC.,
                            a New York corporation
                            WM. A. SMITH CONSTRUCTION CO., INC.,
                            a Texas corporation
                            WOOD WASTE ENERGY, INC.,
                            a Virginia corporation
                            W. T. BYLER CO., INC.,
                            a Texas corporation

                            By:
                               --------------------------------
                            Name:   Michael R. Azarela
                            Title:  Executive Vice President of each of
                                    the foregoing Guarantors

                            F&V METRO RW, INC.,
                            a Delaware corporation
                            RAILWORKS CANADA, INC.
                            a Delaware corporation

                            By:
                                -------------------------------
                            Name:   John P. Nuzzo
                            Title:  Assistant Secretary of each of the
                                    foregoing Guarantors

                            By:
                               --------------------------------
                            Name:   Michael R. Azarela
                            Title:  Executive Vice President of each of
                                    the foregoing Guarantors

                            DURA-WOOD LLC,
                            a Delaware limited liability company

                            By:     MCCORD TREATED WOOD, INC.,
                                    an Alabama corporation, its managing member

                                    By:
                                       -----------------------------
                                    Name:    Michael R. Azarela
                                    Title:   Executive Vice President

                           [Signature Pages Continue]


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<PAGE>   15


COLLATERAL
AGENT:                              BANK OF AMERICA, N.A.,
                                    as Collateral Agent

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



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