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                                                                   EXHIBIT 10.10
GROUPE CEDAR CANADA INC./
CEDAR GROUP CANADA INC.
500 Notre-Dame
Lachine, Quebec
H8S 2B2



RE:      LETTER OF CREDIT FINANCING SUPPLEMENT

Dear Sirs:

Reference is made to the Credit Agreement bearing formal date of September 12,
1997 entered into among yourselves, Dominion Bridge Corporation, Dominion
Bridge, Inc., Steen Contractors Limited, Industries Davie Inc./Davie Industries
Inc., Cedar Group Australia PTY Limited, Les Entrepreneurs Becker Inc./Becker
Contractors Inc., Becker Contractors Limited, MIL Intermodal Inc., the Lenders
from time to time party thereto and us, as agent for the Lenders, as
supplemented, amended, restated, replaced or otherwise modified from time to
time ("Agreement"). The terms hereinafter appearing but not otherwise defined
herein shall have the meanings given in the Agreement.

From time to time, in order to assist you in establishing or opening Letters of
Credit with a Bank or trust company ("Bank"), you may request us to join in the
applications or act as applicant for such Letters of Credit and/or guarantee
payment or performance of your obligations pursuant to the Letters of Credit and
any drafts or acceptances thereunder, thereby lending our credit to you. These
arrangements shall be handled by us subject to the following terms and
conditions.

A. Our assistance in this matter shall at all times and in all respects be in
our sole discretion. The amount and extent of the Letters of Credit and the
terms and conditions thereof and of any drafts or acceptances thereunder, shall
in all respects be determined solely by us and shall be subject to change,
modification and revision by us, at any time and from time to time.

B. Any indebtedness, liability or obligation of any nature whatsoever, arising
or incurred in connection with any Letters of Credit, guarantees, drafts, or
acceptances thereunder or otherwise, including, without limitation, all amounts
due or which may become due under the Letters of Credit, guarantees, or any
drafts or acceptances thereunder, all amounts charged or chargeable to you or to
us by any Bank, other financial institutions or correspondent Bank which opens,
issues or is involved with any Letters of Credit; any other Bank charges, fees
and commissions; duties and taxes, costs of insurance; all such other charges
and expenses which may pertain either directly or 


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indirectly to the Letters of Credit, drafts, acceptances, guarantees or to the
goods or documents relating thereto, and our charges as herein provided, shall
be incurred solely as an accommodation to you and for your account, shall
constitute "Obligations" (as defined in the Agreement), may be charged by us to
your account thereunder at any time without notice to you, shall be secured by
all security which you have heretofore granted to us or hereafter grant to us
(including without limitation all inventory acquired under the Letters of
Credit, all documents evidencing such inventory, and the proceeds thereof),
shall bear interest at the rates provided for in the Agreement, and shall be
repayable to us on demand.

C. You unconditionally agree to indemnify us and hold us harmless from and
against any and all loss, claim or liability arising from any transactions,
occurrences, errors or omissions relating to Letters of Credit established or
opened for your account; the goods acquired thereunder ("Goods"); the documents
evidencing the Goods ("Documents"); any discrepant or nonconforming provisions
thereof; steamship or airway guarantees, releases, indemnities or delivery
orders or similar documents; any drafts or acceptances; and all obligations
hereunder, including, but not limited to, any such loss, claim or liability due
to any action, errors or omissions attributable to any Bank, to us (save and
except if caused by our wilful misconduct or gross negligence), or to any other
entity, or any other cause. Your unconditional obligation to us hereunder shall
not be modified or diminished for any reason or in any manner whatsoever.

D. We shall not be responsible for: the existence, character, quality, quantity,
condition, packing, value or delivery of the Goods; any difference or variation
in the character, quality, quantity, condition, packing, value or delivery of
any Goods from that expressed in the Documents; the validity, sufficiency, or
genuineness of any Documents or of any endorsements thereon, even if such
Documents should in fact prove to be in any or all respects invalid,
insufficient, fraudulent or forged; any discrepant or nonconforming provisions
in any Documents; the time, place, manner or order in which shipment is made;
partial or incomplete shipment, or failure or omission to ship any or all of the
Goods referred to in the Letters of Credit or Documents; any deviation from
instructions; delay, default, or fraud by the shipper and/or anyone else in
connection with the Goods or the shipping thereof; or any breach of contract
between the shipper or vendors and yourselves. Furthermore, without being
limited by the foregoing, we shall not be responsible for any act or omission
with respect to or in connection with any of the Goods or the Documents.

E. You agree that any action taken by us, or any action


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taken by any Bank under or in connection with the Letters of Credit, the
guarantees, the drafts or acceptances, or the Goods or the Documents, shall be
binding on you and shall not result in any liability on our part to you. In
furtherance thereof, we shall have the full right and authority to take any of
the following actions in our name or yours (and you agree that you shall not
have the right to take any such action without our express written consent in
writing): to clear and resolve any questions of non-compliance of documents; to
give any instructions as to acceptance or rejection of any documents or Goods;
to execute any and all applications for steamship or airways guarantees,
releases, indemnities or delivery orders or similar documents; to grant any
extensions of the maturity of, time of payment for, or time of presentation of,
any drafts, acceptances, or documents; and to agree to any amendments, renewals,
extensions, modifications, changes or cancellations of any of the terms or
conditions of any of the applications, Letters of Credit, drafts or acceptances,
all in our sole name; and the Bank shall be entitled to comply with and honour
any and all such documents or instructions executed by or received solely from
us, all without any notice to or any consent from you.

F. You agree that any necessary import, export or other licenses or certificates
for the import or handling of the Goods will have been promptly procured; all
foreign and domestic governmental laws and regulations relating to the shipment
and importation of the Goods, or the financing thereof will have been promptly
and fully complied with; and any certificates in that regard that we may at any
time request will be promptly furnished. In this connection, you warrant and
represent that all shipments made under any Letters of Credit are in accordance
with the governmental laws and regulations of the countries in which the
shipments originate and terminate, and are not prohibited by any such laws and
regulations. You assume all risk, liability for, and agree to pay and discharge,
all local, state, federal or foreign taxes, duties or levies. Any embargo,
restriction, laws, customs or regulations of any country, state, city or other
political subdivision, where the Goods are or may be located, or wherein
payments are to be made, or wherein drafts may be drawn, negotiated, accepted,
or paid, shall be solely your risk, liability and responsibility.

G. Any rights, remedies, duties or obligations granted or undertaken by you to
any Bank in any application for Letters of Credit, or any standing agreement
relating to Letters of Credit or otherwise, shall be deemed to have been granted
to us and apply in all respects to us and shall be in addition to any rights,
remedies, duties or obligations contained herein or in any other agreements with
us.


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H. You hereby agree that prior to your repayment of all Obligations to us, we
may be deemed to be the absolute owner of, with unqualified rights to possession
and disposition of, the Goods and the Documents, all of which may be held by us
as security as herein provided. Should possession of any Goods or Documents be
transferred to you, they shall continue to serve as security as herein provided,
and may be sold, transferred or disposed of only as hereinabove provided.

I. The terms and provisions of all agreements executed by you in our favour
granting collateral security for the Obligations shall apply with equal force to
the Goods and the Documents, including, without limitation, provisions relating
to the insurance, maintenance and surrender.

J. In addition to any charges, fees or expenses charged to us directly or for
your account by any Bank in connection with these transactions (all of which
will be charged to your account as and when made by the Bank shall be conclusive
on us), you will pay us and we shall be entitled to charge your account with the
following:

         1.       Interest at the rate set forth in the Agreement with
                  respect to Revolving Credit Loans on all payments made by
                  us relating directly or indirectly to the Letters of
                  Credit or any guarantees given by us in connection
                  therewith; and

         2.       A fee with respect to each Letter of Credit, used or
                  unused, at the rate set forth in the Agreement.

                  For the purpose of the foregoing, Letters of Credit will be
deemed to include not only Letters of Credit established or opened for you with
our assistance as hereinabove provided, but also other letters of credit
established or opened for you by other institutions with respect to which we are
or hereafter become obligated to indemnify such institutions.

K. In the event that this agreement is addressed to and accepted by more than
one person, such persons shall be solidarily bound, obliged and liable to us for
the performance of all obligations hereunder and all references herein to the
words "you" and "yours" or similar references shall be deemed to be references
to such persons solidarily.


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                  This Agreement, which is subject to modification only in
writing, is supplementary to, and is to be considered as a part of, the 
Agreement and shall take effect when dated, and signed by one of our officers.

DATED THE        DAY OF SEPTEMBER, 1997.

BNY FINANCIAL CORPORATION-CANADA,
ACTING FOR ITSELF AS LENDER AND AS
AGENT FOR THE OTHER LENDERS FROM
TIME TO TIME PARTIES TO THE AGREEMENT.



PER:  /s/ Frank Imperato
      -----------------------------

We hereby agree to and accept the foregoing agreement and all of the foregoing
provisions, terms and conditions thereof.


DATED THE        DAY OF SEPTEMBER, 1997.


GROUPE CEDAR CANADA INC./
CEDAR GROUP CANADA INC.


PER:  /s/ Michel L. Marengere
     ----------------------------
          



DOMINION BRIDGE CORPORATION (GUARANTOR)


PER:  /s/ Michel L. Marengere
     ----------------------------


DOMINION BRIDGE, INC.  (GUARANTOR)


PER:  /s/ Michel L. Marengere
     ----------------------------


STEEN CONTRACTORS LIMITED  (GUARANTOR)


PER:  /s/ Michel L. Marengere
     ----------------------------


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INDUSTRIES DAVIE INC./
DAVIE INDUSTRIES INC.  (GUARANTOR)


PER:  /s/ Michel L. Marengere
     ----------------------------


CEDAR GROUP AUSTRALIA PTY LIMITED  (GUARANTOR)


PER:  /s/ Michel L. Marengere
     ----------------------------


LES ENTREPRENEURS BECKER INC./ (GUARANTOR)
BECKER CONTRACTORS INC.


PER:  /s/ Michel L. Marengere
     ----------------------------


BECKER CONTRACTORS LTD.  (GUARANTOR)


PER:  /s/ Michel L. Marengere
     ----------------------------


MIL INTERMODAL INC.  (GUARANTOR)


PER:  /s/ Michel L. Marengere
     ----------------------------