DRAVO CORPORATION
                                   BY-LAWS
                          As Amended March 31, 1994


                                  ARTICLE I
                             Board of Directors

     SECTION 1. The Board of Directors shall consist of not less than seven and
not more than twelve persons to be elected by the shareholders as herein
provided, the exact number to be determined from time to time by proper
resolution of the Board of Directors. The Directors shall be classified with
respect to the time during which they shall severally hold office, by dividing
them into three classes, each consisting as nearly as possible of the same
number of Directors. At each annual meeting of the shareholders, Directors in
the number for those whose terms then expire shall be elected to serve for
terms of three years, except that the number of Directors to be elected to such
terms shall be adjusted if the number of Directors shall have been decreased
as provided herein so as to eliminate the place of a Director whose term then
expires.

     Nominations for election to the Board of Directors may be made by the
Board of Directors or by any shareholder of the Corporation entitled to notice
of, and to vote at, any meeting called for the election of Directors.
Nominations, other than those made by or on behalf of the Board of Directors
of the Corporation, shall be noticed in writing and shall be received by the
Secretary of the Corporation not later than (i) with respect to an election of
directors to be held at an annual meeting of shareholders, ninety (90) days
prior to the anniversary date of the immediately preceding annual meeting, and
(ii) with respect to an election of directors to be held at a special meeting
of shareholders, the close of business on the fifteenth (15th) day following
the date on which notice of such meeting is first given to shareholders or
public disclosure of the meeting is made. Such notification shall contain the
following information to the extent known to the notifying shareholder: (a) the
name and residence address of each proposed nominee and of the notifying
shareholder; (b) the principal occupation of each proposed nominee; (c) a
representation that the notifying shareholder intends to appear in person or
by proxy at the meeting to nominate the person or persons specified in the
notice; (d) the total number of shares of the Corporation that will be voted
for each proposed nominee; (e) the total number of shares of the Corporation
owned by the notifying shareholder; (f) a description of all arrangements or
understandings between the notifying shareholder and each nominee and any other
person or persons (naming such person or persons) relating to such nomination
or nominations by the notifying shareholder; (g) such other information
regarding each nominee proposed by such shareholder as would be required to be
included in a proxy statement filed with the Securities and Exchange
Commission; and (h) the consent of each nominee to serve as a director of the
Corporation if so elected. If the information submitted to the Corporation
within the time prescribed above is determined by the Chairman of the Board of
the Corporation to be deficient in any manner, the Chairman shall advise the
notifying shareholder in writing of such deficiencies not later than the close
of business on the fifth (5th) day following the date that the Corporation





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first received written notice of the nomination made by the notifying 
shareholder. The notifying shareholder must thereafter cure such deficiencies
by sending a revised notification to the Secretary of the Corporation setting
forth the required information which must be received by the Secretary in 
writing not later than the fifth (5th) day following the date that the 
notifying shareholder received notice from the Corporation of the deficiencies
in the notifying shareholder's written nomination. Notwithstanding the above,
these nominating procedures shall not apply to any special meeting of the 
shareholders of the Corporation called for the election of directors for which
notice of the meeting was not given to shareholders at least (20) days
prior to the meeting. The chairman may disregard and refuse to recognize
any nomination determined by him not to have been made in accordance with the
foregoing procedures.

     If a vacancy occurs in the Board of Directors from any cause, including
any increase in the number of Directors in the manner prescribed in this
Section, a majority of the remaining members of the Board of Directors, though
less than a quorum, shall have the power to elect a Director to fill such
vacancy to serve for the balance of the unexpired term of the vacating director
and until his or her successor has been elected and qualified.

     In the case of an increase in the number of Directors in the manner
specified in this Section, the additional offices so created shall be assigned
by the Board of Directors to the appropriate class so that the three classes
shall continue to consist, as nearly as possible, of the same number of
Directors.

     At any shareholders' meeting at which Directors are to be elected,
separate elections shall be held for the Directors of each class then to be
elected.

     The Directors shall hold office during the terms for which they have been
elected and until their successors are elected and qualified.

     SECTION 2. The Board of Directors may, by resolution adopted by a majority
of the whole Board, designate one or more committees, each committee to consist
of two or more of the Directors of the Corporation. Standing committees shall
include the Audit and Finance Committee and the Compensation and Nominating
Committee, each of which shall be comprised exclusively of Directors who are
not current employees of the Corporation.


     SECTION 3. The Board of Directors, as soon as reasonably possible after
each annual meeting of shareholders, shall hold a meeting to organize, elect
officers of the Corporation and transact other business.

     Regular meetings of the Board of Directors may be held without notice at
such time and place as shall from time to time be determined by the Board of
Directors and may be adjourned by the members present to any other time and
place.

     Special meetings may be called at any time by the chief executive officer
or any two members of the Board of Directors upon at least 24 hours' notice,
which need not be in writing.

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     A majority of the Directors in office shall constitute a quorum for the
transaction of business.

     If all the Directors shall severally or collectively consent in writing
to any action to be taken by the Corporation, such action shall be as valid
corporate action as though it had been authorized at a meeting of the Board of
Directors.

     One or more Directors may participate in a meeting of the Board of
Directors, or of a committee thereof, by means of conference telephone or
similar communications equipment by means of which all persons participating
in the meeting can hear each other.

     SECTION 4. The Board of Directors shall have the right to adopt such rules
and regulations for the conduct of business, and from time to time alter and
amend the same, as to them may seem proper.

     SECTION 5. The Board of Directors (or the Compensation Committee by
delegation from the Board), shall fix the compensation of the officers of the
Corporation and such other employees who are designated by the Board of
Directors as holding major positions of authority in the Corporation.


                                 ARTICLE III
                                  Officers

     SECTION 1. The officers of the Corporation to be elected by the Board of
Directors shall consist of a Chairman, one or more Vice Chairman (any one or
more of whom may have added to his title another word or words specially
designating the further powers and duties assigned to that officer), a
President, one or more Vice Presidents (any one or more of whom may be
designated an Executive Vice President, Senior Vice President, Group Vice
President or have added to his title another word or words specially
designating the further powers and duties assigned to that officer), a 
Treasurer, a Controller and a Secretary, who shall hold office until their
respective successors are duly elected and qualified or until the earlier
death, resignation or removal from office of any of them.

     SECTION 2. Subordinate officers to be appointed by the Board of Directors
shall include one or more assistant secretaries and one or more assistant
treasurers.

                                 ARTICLE III
                           Duties of the Chairman

     SECTION 1. The Chairman, who shall be elected from among the Directors,
shall preside at all meetings of the shareholders and of the Board of Directors
at which he shall be present. The Chairman shall be the chief executive officer
of the Corporation and, subject to the control of the Board of Directors, shall
have general management and supervision over the business and affairs of the
Corporation. In the absence or inability to act of the Chairman, the officer
or officers designated from time to time by the Board of Directors shall
perform the duties pertaining to the office of Chairman.



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                                 ARTICLE IV
                        Duties of the Vice Chairmen 

     SECTION 1. The Vice Chairmen, who shall be elected from among the
Directors, shall perform such duties as shall be prescribed time to time by the
Board of Directors or the chief executive officer.


                                  ARTICLE V
                          Duties of the President 

     SECTION 1. The President shall be the chief operating officer of the
Corporation and, subject to the control of the Board of Directors and the
Chairman, shall be in direct and active charge of the business and affairs of
the Corporation. In the absence or inability to act of the President, the
officer or officers designated from time to time by the Board of Directors
shall perform the duties pertaining to the office of President.


                                 ARTICLE VI
                        Duties of the Vice Presidents

     SECTION 1. The Vice Presidents shall perform such duties as shall be
prescribed from time to time by the Board of Directors or the chief executive
officer.


                                 ARTICLE VII
                          Duties of the Secretary 

     SECTION 1. The Secretary shall, under the direction of the chief executive
officer, record the proceeding of all meetings of the Board of Directors and
of the shareholders for presentation in a suitable book. The Secretary shall
notify the shareholders of all annual and special meetings and the members of
the Board of Directors of all special meetings, have charge of the corporate
seal and perform all the duties which are customary and incident to the office
of Secretary of like companies.




                                ARTICLE VIII
                          Duties of the Treasurer 

     SECTION 1. The Treasurer shall, under the direction of the Vice President
in charge of financial affairs, have general charge of the funds of the
Corporation and shall make such reports of the receipts and disbursements in
such form and manner as the Board of Directors may direct. He shall if so
directed by the chief executive officer, attend any or all meetings of the
Board of Directors and report on his activities as the chief executive officer
may prescribe.





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                                 ARTICLE IX
                          Duties of the Controller 

     SECTION 1. The Controller shall, under the direction of the Vice President
in charge of financial affairs, maintain adequate records of all assets,
liabilities and transactions of the Corporation; cause adequate audits to be
currently and regularly made; prepare financial, cost and tax reports and other
reports of a financial and accounting nature required by governmental agencies;
and in conjunction with other officers and heads of departments initiate and
enforce controls and procedures whereby the business of the Corporation shall
be conducted with the maximum of efficiency and economy. He shall, if so
directed by the chief executive officer, attend any or all meetings of the
Board of Directors and report on his activities as the chief executive officer
may prescribe.


                                  ARTICLE X
                        Checks, Notes and Contracts 

     SECTION 1. All checks drawn upon the funds of the Corporation and all
promissory notes, drafts, bills of exchange or other negotiable instruments
shall be signed in the name of the Corporation by such person or persons as the
Board of Directors may from time to time designate.


     SECTION 2.  All written contracts other than those mentioned in Section
1 of this Article shall be signed in the name of the Corporation by the
Chairman or a Vice Chairman or the President or a Vice President, unless
otherwise directed by the Board of Directors.


                                 ARTICLE XI
                                  Elections

     SECTION 1. In elections of directors by shareholders, voting need not be
by ballot unless required by vote of the shareholders before the voting for
election of directors begins.

     Election of officers shall be in such manner as a majority of the
Directors present and voting at a duly organized meeting may determine.


                                 ARTICLE XII
                                   Offices

     SECTION 1. The registered office of the Corporation shall be in the City
of Pittsburgh, County of Allegheny, State of Pennsylvania, but the Board of
Directors may establish another office or other offices at any place or places
in the state of Pennsylvania or elsewhere.







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                                ARTICLE XIII
                                    Seal 

     SECTION 1. The seal of the Corporation shall have inscribed thereon the
name of the Corporation, the year of its creation, the name of the State under
whose laws it was created and the words "Corporate Seal".


                                 ARTICLE XIV
                        Meetings of the Shareholders

     SECTION 1. Meetings of the shareholders may be held at such places within
or without the State of Pennsylvania as may be fixed by the Board of Directors.

     The annual meeting of the shareholders of the Corporation for the election
of Directors shall be held on such date and at such time and place as may be
fixed from time to time by the Board of Directors, provided, however, that in
fixing the date, time and place of said meeting the Board of Directors shall
comply with all applicable statutes and regulations as well as the rules of the
New York Stock Exchange.


     SECTION 2. Special meetings of the shareholders may be called at any time
by the Board of Directors, the Chairman of the Board or the President of the
Corporation. Notice shall be given by the Secretary of the time and place of
holding the annual and any special meeting of the shareholders by mailing such
notice to the addresses of said shareholders, as shown by the share register
or the records of the Corporation, at least five days prior to the date of the
meeting, except when a longer period of notice is required by law.

     SECTION 3. Unless otherwise provided in a resolution of the Board of
Directors with respect to any meeting of shareholders and stated in the notice
of the meeting, the presence of shareholders entitled to cast at least a
majority of the votes that all shareholders are entitled to cast on a
particular matter to be acted upon at the meeting shall constitute a quorum for
purposes of consideration and action on the matter. If no quorum be present at
any meeting so called, the holders of less than a majority of said shares may
meet and adjourn the meeting from time to time until a quorum be present or
until action may be taken in the absence of a quorum in the manner prescribed
by law.


                                 ARTICLE XV
                             Share Certificates

     SECTION 1. Share certificates shall be issued to the shareholders and
transfers thereof shall be made by a transfer agent, if one or more transfer
agents are appointed by the Board of Directors, otherwise by the Secretary or
Assistant Secretary. Transfers shall be made in person or by power of attorney
on the books of the Corporation on the surrender of the certificates. The share
certificates shall be signed by the Chairman, the President or a Vice President
or other officer designated by the Board of Directors, countersigned by the
Treasurer or Assistant Treasurer or other officers designated by the Board of
Directors and sealed with the seal of the Corporation.

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     One or more transfer agents and registrars of the shares of stock of the
Corporation may be appointed by the Board of Directors. The signatures,
countersignatures, and seal, or any of them on the share certificates may be
executed in facsimile, engraved or printed, provided that the share
certificates are signed or countersigned by a corporate transfer agent or by
a corporate registrar other than the Corporation itself, appointed by the Board
of Directors.


                                 ARTICLE XVI
                                Resignations

     SECTION 1. Any Director or officer may resign his office at any time, such
resignation to be in writing and to take effect from the time of its receipt
by the corporation, unless some time be fixed in the said resignation, and then
from that time. The acceptance of a resignation shall not be required to make 
it effective.


                                ARTICLE XVII
                               Indemnification

     SECTION 1. The Corporation shall indemnify every person who is or was a
party or is threatened to be made a party to or is involved (as a witness or
otherwise) in any threatened, pending or completed action, suit or proceeding,
whether civil, criminal, administrative or investigative and whether or not by
or in the right of the Corporation or otherwise (hereafter a "proceeding"), by
reason of the fact that he or she is or was a Director or officer or employee
of the Corporation, or is or was serving at the request of the Corporation as
a Director, officer or trustee or employee of another corporation, partnership,
joint venture, trust or other enterprise, including service with respect to an
employee benefit plan, or by reason of any action alleged to have been taken
or not taken by him or her while acting in any such capacity, against expenses
(including attorneys' fees) and all liability and loss, including  judgments, 
fines,  ERISA  excise  taxes  and  penalties and amounts paid or to be paid in
settlement (whether with or without court approval), actually and  reasonable 
 incurred by him or her in connection with such threatened, pending or
completed action, suit or proceeding, except to the extent prohibited by law
as the same exists or may hereafter be amended (except in the case of any such
amendment which has the effect of narrowing indemnification rights that the
Corporation was permitted to provide prior to such amendment); provided,
however, that except with respect to claims described in Section 2 hereof, the
Corporation shall indemnify any such person seeking indemnification in
connection with a proceeding (or part thereof), initiated by such person only
if such proceeding (or part thereof) was authorized by the Board of Directors
of the Corporation. Subject to the foregoing indemnification, the right to
indemnification conferred in this Section shall include the right to be paid
by the Corporation expenses incurred; provided, however, that to the extent
required by law, the payment of such expenses in advance of the final
disposition of a proceeding shall be made only upon receipt of an undertaking
by or on behalf of such person to repay such amounts if it shall ultimately be
determined that he or she is not entitled to be indemnified under this Article
or otherwise.



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     SECTION 2. If a claim under Section 1 is not paid in full by the
Corporation within forty-five (45) days after a written claim has been received
by the Corporation, the claimant may, at any time thereafter, bring suit
against the Corporation to recover the unpaid amount of the claim. The claimant
shall also be entitled to be paid the expenses of prosecuting such claim to the
extent he or she is successful in whole or in part on the merits or otherwise
in establishing his or her right to indemnification or to the advancement of
expenses.

     SECTION 3. The right to indemnification, including the right to the
advancement of expenses, conferred in this Article shall not be exclusive of
any other rights to which a person seeking indemnification or advancement of
expenses hereunder may be entitled under any by-law, agreement, vote of
shareholders, or directors or otherwise, both as to action in his or her
official capacity and as to action in any other capacity while holding that
office.

     SECTION 4. The Corporation may create a fund of any nature, which may, but
need not be, under the control of a trustee, or otherwise secure or insure in
any manner its indemnification obligations, including its obligation to advance
expenses, whether arising under or pursuant to this Article or otherwise.

     SECTION 5. The Corporation shall have the express authority to enter into
such agreements as the Board of Directors deem appropriate for the
indemnification of, including the advancement of expenses to, present or future
Directors, officers and employees of the Corporation in connection with their
service to, or status with, the Corporation or any other corporation,
partnership, joint venture, trust or other enterprise, including any employee
benefit plan, for whom such person is serving at the request of the
Corporation.


     SECTION 6. The right to indemnification, including the right to the
advancement of expenses provided herein, shall be a contract right, shall
continue as to a person who has ceased to be a director, officer, employee, or
to serve in any other of the capacities described herein, and shall inure to
the benefit of the heirs, executors and administrators of such person.
Notwithstanding any amendment, alteration or repeal of this Article or any of
its provisions or the adoption of any provision inconsistent with this Article
or any of its provisions, any person who is or was a director, officer or
employee or is or was serving at the request of the Corporation as a director,
officer, employee, or trustee of another corporation or of a partnership, joint
venture, trust or other enterprise, including service with respect to employee
benefit plans, shall be entitled to indemnification, including the right to the
advancement of expenses, in accordance with the provisions hereof and thereof
with respect to any action taken or omitted prior to such amendment, alteration
or repeal or the adoption of such inconsistent provision except to the extent
such amendment, alteration, repeal or inconsistent provisions provides broader
rights with respect to indemnification, including the advancement of expenses,
than the Corporation was permitted to provide prior to the amendment,
alteration, repeal, or the adoption of such inconsistent provision or to the
extent otherwise prescribed by law.




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                                ARTICLE XVIII
             By-Laws--Adoption, Alteration, Amendment and Repeal

     SECTION 1. The By-Laws of the Corporation may be adopted, altered, amended
or repealed by a majority vote of the shareholders present and voting at any
regular or special meeting duly convened after notice to the shareholders of
that purpose or by a majority vote of the members of the Board of Directors
present and voting at any regular or special meeting, subject always to the
power of the shareholders to change any such action taken by the Board of
Directors.


                                 ARTICLE XIX
                      Limitation on Director Liability

     SECTION 1.  A director of the Corporation shall not be personally liable
for monetary damages for any action taken or failure to take any action unless
the director has breached or failed to perform the duties of his office under
Section 8363 of the Directors' Liability Act and such breach or failure to
perform constitutes self-dealing, willful misconduct or recklessness; provided,
however, that the foregoing provision shall not eliminate or limit the
liability of a director (i) for any responsibility or liability of such
director pursuant to any criminal statute, or (ii) for any liability of a
director for the payment of taxes pursuant to local, State or Federal law.  This
Article XIX shall not apply to any actions filed prior to January 27, 1987 or 
to any breach of performance of duty or any failure of performance of duty by
any director occurring prior to January 27, 1987.

     SECTION 2. Notwithstanding any other provision of law, the Articles of
Incorporation or the By-Laws of the Corporation, the affirmative vote of
shareholders entitled to cast at least a majority of the votes which all
shareholders would be entitled to cast in an annual election of directors (or
such greater percentage of votes as shall be required by law) shall be required
to adopt any amendment, alteration or repeal of, or to adopt any provision
inconsistent with, this Article XIX or any of its provision, including this
Section 2. Neither the repeal or modification of this Article XIX or any of its
provisions nor the adoption of any provision inconsistent with this Article XIX
or any of its provisions shall adversely affect any limitation on the personal
liability of a director of the Corporation existing at the time of such repeal
or modification or the adoption of such inconsistent provision.


                                 ARTICLE XX
      Applicability of Certain provisions of the Pennsylvania Business 
                               Corporation Law

     SECTION 1. Subchapters G (relating to Control Share Acquisitions), H
(relating to Disgorgement by Certain Controlling Shareholders Following
Attempts to Acquire Control), I (relating to Severance Compensation for
Employees Terminated Following Certain Control-Share Acquisitions), and J
(relating to the Status of Labor Contracts Following Certain Business
Combination Transactions) of Chapter 25 of the Pennsylvania Business
Corporation Law shall not be applicable to the Corporation.

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