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                                                                     Exhibit 4.2




                     WASHINGTON GROUP INTERNATIONAL, INC.

                                  ----------

                          REGISTRATION RIGHTS AGREEMENT

                                  ----------

                             Dated January 25, 2002


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                                TABLE OF CONTENTS

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                                                                            PAGE
                                                                            ----
<S>                                                                         <C>

ARTICLE I   REGISTRATION RIGHTS..............................................1

      SECTION 1.1 DEMAND REGISTRATION........................................1
            (a)   REGISTRATION...............................................1
            (b)   DEMANDS....................................................2
            (c)   NUMBER OF DEMANDS..........................................2
            (d)   EFFECTIVE REGISTRATION STATEMENT...........................3
            (e)   SATISFACTION OF OBLIGATIONS................................3
            (f)   REGISTRATION STATEMENT FORM................................3
            (g)   RESTRICTIONS ON DEMAND REGISTRATIONS.......................3
            (h)   PARTICIPATION IN DEMAND REGISTRATIONS......................4
            (i)   SELECTION OF UNDERWRITERS..................................4

      SECTION 1.2 PIGGYBACK REGISTRATIONS....................................5
            (a)   RIGHT TO PIGGYBACK.........................................5
            (b)   PRIORITY ON PIGGYBACK REGISTRATIONS........................5
            (c)   WITHDRAWAL BY THE COMPANY..................................6

      SECTION 1.3 SHELF REGISTRATION.........................................7

      SECTION 1.4 WITHDRAWAL RIGHTS..........................................8

      SECTION 1.5 HOLDBACK AGREEMENTS........................................9

      SECTION 1.6 REGISTRATION PROCEDURES....................................9
            (a)   REGISTRATION...............................................9
            (b)   UNDERWRITING..............................................13
            (c)   RETURN OF PROSPECTUSES....................................13

      SECTION 1.7 REGISTRATION EXPENSES.....................................13

      SECTION 1.8 INDEMNIFICATION...........................................14
            (a)   BY THE COMPANY............................................14
            (b)   BY THE STOCKHOLDERS.......................................14
            (c)   NOTICE....................................................15
            (d)   DEFENSE OF ACTIONS........................................15
            (e)   SURVIVAL..................................................15
            (f)   CONTRIBUTION      15    ....................................

      SECTION 1.9 RESTRICTIONS ON TRANSFER..................................16

ARTICLE II MISCELLANEOUS....................................................17

            SECTION 2.1 Headings............................................17

            SECTION 2.2 Entire Agreement....................................17

            SECTION 2.3 Termination of Certain Rights.......................18

            SECTION 2.4 Rule 144............................................18

            SECTION 2.5 Notices.............................................18

            SECTION 2.6 Applicable Law......................................19


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            SECTION 2.7 Severability........................................19

            SECTION 2.8 Successors; Assigns.................................19

            SECTION 2.9 Amendments..........................................19

            SECTION 2.10 Waiver.............................................19

            SECTION 2.11 Counterparts.......................................19

            SECTION 2.12 Submission To Jurisdiction.........................19

ARTICLE III DEFINITIONS.....................................................20
                  (a)   "Affiliate".........................................20
                  (b)   "Affiliated Stockholders"...........................20
                  (c)   "Board".............................................20
                  (d)   "Commission"........................................20
                  (e)   "Common Stock"......................................20
                  (f)   "Company"...........................................20
                  (g)   "Demand"............................................20
                  (h)   "Demand Registration"...............................21
                  (i)   "Demanding Holder"..................................21
                  (j)   "Effective Date"....................................21
                  (k)   "Exchange Act"......................................21
                  (l)   "Form S-3"..........................................21
                  (m)   "Internal Expenses".................................21
                  (n)   "Losses"............................................21
                  (o)   "Market Price"......................................21
                  (p)   "Maximum Demand Number".............................21
                  (q)   "Maximum Piggyback Number"..........................21
                  (r)   "Other Demand Rights"...............................21
                  (s)   "Other Demanding Sellers"...........................21
                  (t)   "Person"............................................21
                  (u)   "Piggyback Notice"..................................22
                  (v)   "Piggyback Registration"............................22
                  (w)   "Piggyback Sellers".................................22
                  (x)   "Plan"..............................................22
                  (y)   "Primary Offering"..................................22
                  (z)   "Public Offering"...................................22
                  (aa)  "Registrable Securities"............................22
                  (ab)  "Registration Expenses".............................22
                  (ac)  "Requisite Amount"..................................22
                  (ad)  "Securities Act"....................................22
                  (ae)  "Shelf Notice"......................................22
                  (af)  "Shelf Registration Statement"......................22
                  (ag)  "Suspension Period".................................23
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                          REGISTRATION RIGHTS AGREEMENT
                                       OF
                      WASHINGTON GROUP INTERNATIONAL, INC.

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

      REGISTRATION RIGHTS AGREEMENT, dated as of January 25, 2002, among
Washington Group International, Inc., a Delaware corporation (the "COMPANY"),
and the other undersigned parties hereto.

      Pursuant to the Second Amended Joint Plan of Reorganization of Washington
Group International, Inc. and its affiliated debtors and debtors-in-possession
(as amended or modified, the "PLAN"), confirmed on December 21, 2001, the
Company has agreed, among other things, to authorize 100 million shares of new
common stock, par value $0.01 per share (the "COMMON STOCK"), of which
approximately 20 million shares will be issued in connection with the Plan to
members of Class 6. This agreement shall become effective upon the issuance of
such securities pursuant to the Plan (the "EFFECTIVE DATE"). Certain capitalized
terms used in this agreement are defined in Article IV hereof. References to
sections shall be to sections of this agreement.

      WHEREAS pursuant to Section 5.5 of the Plan, the Company has agreed to
grant the registration rights set forth herein to each holder of an Allowed
Class 6 Claim (as defined in the Plan) who by virtue of holding Common Stock
distributed under the Plan and/or its relationship with the Company could
reasonably be deemed to be an affiliate of the Company under applicable
securities laws and who requests in writing that the Company execute this
Agreement (each such holder, an "AFFILIATED STOCKHOLDER").

      NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth herein and for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties agree as follows:

                                    ARTICLE I

                               REGISTRATION RIGHTS

            Section 1.1 DEMAND REGISTRATION.

            (1) REGISTRATION. At any time after the Effective Date, Affiliated
Stockholders holding the Requisite Amount of Registrable Securities shall be
entitled to make a written request of the Company (a "DEMAND") for registration
under the Securities Act of all or part of their Registrable Securities (a
"DEMAND REGISTRATION") and thereupon the Company will, subject to the terms of
this Agreement, use commercially reasonable efforts to effect the registration
under the Securities Act of:

                  (1) the Registrable Securities which the Company has been so
requested to register by such Affiliated Stockholders for disposition in
accordance with the intended method of disposition stated in such request;

                  (2) all other Registrable Securities which the Company
has been requested to register pursuant to Section 1.1(b) hereof; and

                  (3) all shares of Common Stock which the Company may elect to
register in connection with the offering of Registrable Securities pursuant to
this Section 1.1;


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all to the extent necessary to permit the disposition (in accordance with the
intended methods thereof) of the Registrable Securities and the additional
shares of Common Stock, if any, so to be registered; PROVIDED THAT the Company
shall not be required to effect a Demand Registration unless (x) a single holder
of Registrable Securities has requested the registration of a number of shares
of Registrable Securities held by such holder which is equal to or greater than
10% of the shares of Common Stock at the time outstanding, and (y) the aggregate
number of shares of Registrable Securities requested to be registered by all
holders of Registrable Securities in such Demand Registration is equal to or
greater than 15% of the number of shares of Common Stock at the time
outstanding.

            (2) DEMANDS. A Demand shall specify: (i) the aggregate number of
Registrable Securities requested to be registered in such Demand Registration,
(ii) the intended method of disposition in connection with such Demand
Registration, to the extent then known, and (iii) the identity of the Affiliated
Stockholder or Affiliated Stockholders (each, a "DEMANDING HOLDER") requesting
such Demand. Within fifteen (15) days after receipt of a Demand, the Company
shall give written notice of such Demand to all other Affiliated Stockholders.
Subject to Section 1.1(h), the Company shall include in such registration all
Registrable Securities with respect to which the Company has received a written
request for inclusion therein within fifteen (15) days after the Company's
notice required by this paragraph has been given. Such written notice shall
comply with the requirements of a Demand as set forth in this Section 1.1(b).

            (3) NUMBER OF DEMANDS. Each Affiliated Stockholder shall be entitled
to one (1) Demand Registration; PROVIDED THAT, in the aggregate, Affiliated
Stockholders shall be entitled to no more than two (2) Demand Registrations.

            (4) EFFECTIVE REGISTRATION STATEMENT. A Demand Registration shall
not be deemed to have been effected (i) unless a registration statement with
respect thereto has become effective; PROVIDED THAT a registration which does
not become effective after the Company has filed a registration statement with
respect thereto solely by reason of the refusal to proceed of the Affiliated
Stockholders (other than a refusal to proceed based upon the advice of counsel
relating to disclosure in the Registration Statement of a matter with respect to
the Company) shall be deemed to have been effected by the Company at the request
of such Affiliated Stockholders unless the Affiliated Stockholders shall have
elected to pay all Registration Expenses in connection with such registration,
(ii) if, after it has become effective, and as a direct result of the actions of
the Company, such registration becomes subject to any stop order, injunction or
other order or requirement of the Commission or other governmental agency or
court for any reason, or (iii) the conditions to closing specified in the
purchase agreement or underwriting agreement entered into in connection with
such registration are not satisfied, other than by reason of some act or
omission by such Affiliated Stockholders.

            (5) SATISFACTION OF OBLIGATIONS. A registration shall not be treated
as a permitted Demand for a Demand Registration until (i) the applicable
registration statement under the Securities Act has been filed with the
Commission with respect to such Demand Registration (which shall include any
registration statement that is not withdrawn by holders of Registrable
Securities in the circumstances contemplated by Section 1.4), and (ii) such
registration statement

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shall have been maintained continuously effective for a period of sixty (60)
days or such shorter period in the case where all Registrable Securities
included therein have been disposed of thereunder in accordance with the
manner of distribution set forth in such registration statement.

            (6) REGISTRATION STATEMENT FORM. Demand Registrations shall be on
such appropriate registration form of the Commission as shall be selected by the
Company; PROVIDED THAT the Company shall use commercially reasonable efforts to
comply with the requirements for use of a short form registration statement for
the sale of securities under the Securities Act to the extent the same is
applicable to the Company.

            (7) RESTRICTIONS ON DEMAND REGISTRATIONS. The Company shall not be
obligated to (i) maintain the effectiveness of a registration statement under
the Securities Act, filed pursuant to a Demand Registration, for a period longer
than sixty (60) days, or (ii) effect any Demand Registration (A) within six (6)
months of a "firm commitment" underwritten registration in which all Affiliated
Stockholders were given "piggyback" rights pursuant to Section 1.2 hereof and at
least 50% of the number of Registrable Securities requested by such Affiliated
Stockholders to be included in such registration were included, (B) within six
(6) months of any other Demand Registration, or (C) if, in the Company's
reasonable judgment, it is not feasible for the Company to proceed with the
Demand Registration because of the unavailability of audited financial
statements. In addition, the Company shall be entitled to postpone (upon written
notice to all Affiliated Stockholders) for up to one hundred twenty (120) days
the filing or the effectiveness of a registration statement for a Demand
Registration (but no more than twice in any period of twelve (12) consecutive
months) if the Board determines in good faith and in its reasonable judgment
that the Demand Registration or the disclosure of material, non-public
information in connection therewith would have a material adverse affect on the
Company or on any proposal or plan by the Company or any of its subsidiaries to
engage in any debt or equity offering, material acquisition or disposition of
assets, merger, consolidation, tender offer or other similar transaction. In the
event of a postponement by the Company of the filing or effectiveness of a
registration statement for a Demand Registration, the holders of a majority of
Registrable Securities held for all Demanding Holders shall have the right to
withdraw such Demand in accordance with Section 1.4 hereof.

            (8) PARTICIPATION IN DEMAND REGISTRATIONS. The Company shall not
include any securities other than Registrable Securities and Common Stock
included at the Company's election in a Demand Registration, except with the
written consent of the holders of a majority, by number of shares, of the
Registrable Securities held by all the Demanding Holders. If, in connection with
a Demand Registration, any managing underwriter (or, if such Demand Registration
is not an underwritten offering, a nationally recognized independent underwriter
selected by the Company and reasonably acceptable to the holders of a majority
of the Registrable Securities held by all the Demanding Holders and whose fees
and expenses shall be borne solely by the Company) advises the Company, in
writing, that, in its opinion, the inclusion of all of the securities, including
securities of the Company which are not Registrable Securities, sought to be
registered in connection with such Demand Registration would adversely affect
the marketability of the Registrable Securities sought to be sold pursuant
thereto, then the Company shall include in such registration statement only such
securities as the Company is advised by such underwriter can be sold without
such adverse effect (the "MAXIMUM DEMAND NUMBER") as


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follows and in the following order of priority: (i) first, Registrable
Securities requested to be included in such registration by Affiliated
Stockholders, PRO RATA among such Affiliated Stockholders requesting such
registration on the basis of the number of such securities requested to be
included by such Affiliated Stockholders; (ii) second, securities the Company
proposes to sell; and (iii) third, all other securities of the Company duly
requested to be included in such registration statement, PRO RATA on the
basis of the amount of such other securities requested to be included.

            (9) SELECTION OF UNDERWRITERS. If the Demand Registration involves
an underwritten offering, the underwriter or underwriters thereof shall be
selected by the Company and shall be reasonably acceptable to the holders of a
majority, by number of shares, of the Registrable Securities held by all of the
Demanding Holders.

            Section 1.2 PIGGYBACK REGISTRATIONS.

            (1) RIGHT TO PIGGYBACK. Subject to the terms and conditions hereof,
whenever the Company proposes to register any of its equity securities
(including securities convertible into or exchangeable for equity securities)
under the Securities Act (other than a registration by the Company on a
Registration Statement on Form S-4 or a Registration Statement on Form S-8 or
any successor form) (a "PIGGYBACK REGISTRATION"), the Company shall give all
Affiliated Stockholders prompt written notice thereof (but not less than fifteen
(15) business days prior to the filing by the Company with the Commission of any
registration statement with respect thereto). Such notice (a "PIGGYBACK NOTICE")
shall specify, at a minimum, the number of securities proposed to be registered,
the proposed date of filing of such registration statement with the Commission,
the proposed means of distribution, the proposed managing underwriter or
underwriters (if any and if known), and a good faith estimate by the Company of
the proposed minimum offering price of such securities. Upon the written request
of an Affiliated Stockholder (which written request shall specify the number of
Registrable Securities intended to be disposed of by such Affiliated Stockholder
and the intended method of distribution thereof) given within ten (10) business
days after such Piggyback Notice is given to such Affiliated Stockholder, the
Company, subject to the terms and conditions of this Agreement, shall include in
such registration all Registrable Securities held by Affiliated Stockholders
with respect to which the Company has received such written requests for
inclusion.

            (2) PRIORITY ON PIGGYBACK REGISTRATIONS. If, in connection with a
Piggyback Registration, any managing underwriter (or, if such Piggyback
Registration is not an underwritten offering, a nationally recognized
independent underwriter selected by the Company reasonably acceptable to the
holders of a majority, by number of shares, of the Registrable Securities sought
to be included in such Piggyback Registration and whose fees and expenses shall
be borne solely by the Company) advises the Company, in writing, that, in its
opinion, the inclusion of all the securities sought to be included in such
Piggyback Registration by the Company, any Persons who have sought to have
shares registered thereunder pursuant to rights to demand (other than pursuant
to so-called "piggyback" or other incidental or participation registration
rights) such registration (such demand rights being "OTHER DEMAND RIGHTS" and
such Persons being "OTHER DEMANDING SELLERS"), any holders of Registrable
Securities seeking to sell such Registrable Securities in such Piggyback
Registration ("PIGGYBACK SELLERS") and any other proposed sellers,


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as the case may be, would adversely affect the marketability of the
securities sought to be sold pursuant thereto, then the Company shall include
in the registration statement applicable to such Piggyback Registration only
such securities as the Company is so advised by such underwriter can be sold
without such an effect (the "MAXIMUM PIGGYBACK NUMBER"), as follows and in
the following order of priority:

                  (1) if the Piggyback Registration relates to an offering for
the Company's own account (a "PRIMARY OFFERING"), then (A) first, such number of
securities to be sold by the Company as the Company, in its reasonable judgment
and acting in good faith and in accordance with sound financial practice, shall
have determined, (B) second, Registrable Securities of Piggyback Sellers in an
amount sufficient to reduce the amount of such Piggyback Sellers' Registrable
Securities held after the offering to a level that would cause such Piggyback
Sellers to each hold less than ten-percent (10%) of the total issued and
outstanding Common Stock; PROVIDED THAT the Company shall, at the Company's
discretion, include Registrable Securities in this category so as to maximize
the number of Piggyback Sellers whose post-offering ownership of Common Stock is
less than ten percent (10%) of the total issued and outstanding Common Stock;
(C) third, such Registrable Securities duly requested to be included in such
registration statement by any Piggyback Seller (consisting of the remaining
Registrable Securities held by such Piggyback Sellers after application of the
immediately preceding priority category), PRO RATA on the basis of the amount of
such Registrable Securities held by such Piggyback Sellers.

                  (2) if the Piggyback Registration relates to other than a
Primary Offering, then (A) first, such number of securities sought to be
registered by each Other Demanding Seller, PRO RATA in proportion to the number
of securities sought to be registered by all such Other Demanding Sellers, (B)
second, Registrable Securities of Piggyback Sellers in an amount sufficient to
reduce the amount of such Piggyback Sellers' Registrable Securities held after
the offering to a level that would cause such Piggyback Sellers to hold less
than ten-percent (10%) of the total issued and outstanding Common Stock;
PROVIDED THAT the Company shall, at the Company's discretion, include
Registrable Securities in this category so as to maximize the number of
Piggyback Sellers whose post-offering ownership of Common Stock is less than ten
percent (10%) of the total issued and outstanding Common Stock; and (C) third,
such Registrable Securities duly requested to be included in such registration
statement by any Piggyback Seller (consisting of remaining Registrable
Securities held by such Piggyback Seller after application of the immediately
preceding priority category), PRO RATA on the basis of the amount of such
Registrable Securities held by such Piggyback Sellers.

            (3) WITHDRAWAL BY THE COMPANY. If, at any time after giving written
notice of its intention to register any of its securities as set forth in this
Section 1.2 and prior to the time the registration statement filed in connection
with such registration is declared effective, the Company shall determine for
any reason not to register such securities, the Company may, at its election,
give written notice of such determination to each Affiliated Stockholder and
thereupon shall be relieved of its obligation to register any Registrable
Securities in connection with such particular withdrawn or abandoned
registration (but not from its obligation to pay the Registration Expenses in
connection therewith as provided herein). In the event that the Piggyback
Sellers of such a registration hold the Requisite Amount of Registrable
Securities,


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such holders may continue the registration as a Demand Registration pursuant
to the terms of Section 1.1 hereof.

            Section 1.3 SHELF REGISTRATION.

            (1) Subject to Section 1.3(d) hereof, and further subject to the
availability of a Registration Statement on Form S-3 ("FORM S-3") to the
Company, at any time after the Effective Date any Affiliated Stockholder may by
written notice delivered to the Company (the "SHELF NOTICE") require the Company
to file as soon as practicable (but no later than ninety (90) days after the
date the Shelf Notice is delivered), and to use its commercially reasonable
efforts to cause to be declared effective by the Commission (within ninety (90)
days after such filing date), a Form S-3 providing for an offering to be made on
a continuous basis pursuant to Rule 415 under the Securities Act relating to the
offer and sale, from time to time, of the Registrable Securities beneficially
owned by such Affiliated Stockholder and the other Affiliated Stockholders
electing to participate therein as provided in Section 1.3(b) hereof in
accordance with the plan and method of distribution set forth in the prospectus
included in such Form S-3 (the "SHELF REGISTRATION STATEMENT");

            (2) Within ten (10) business days after receipt of a Shelf Notice
pursuant to Section 1.3(a) hereof, the Company will deliver written notice
thereof to each Affiliated Stockholder. Each such Affiliated Stockholder may
elect to participate in the Shelf Registration Statement by delivering to the
Company a written request to so participate within ten (10) business days after
the Shelf Notice is given to any such Affiliated Stockholder.

            (3) Subject to Section 1.3(d), the Company will use its commercially
reasonable efforts to keep the Shelf Registration Statement continuously
effective until the earlier of (i) one (1) year after the Shelf Registration
Statement has been declared effective; and (ii) the date on which all
Registrable Securities covered by the Shelf Registration Statement have been
sold thereunder in accordance with the plan and method of distribution disclosed
in the prospectus included in the Shelf Registration Statement, or otherwise.

            (4) Notwithstanding anything to the contrary contained in this
Agreement, the Company shall be entitled, from time to time by providing written
notice to the Affiliated Stockholders who elected to participate in the Shelf
Registration Statement, to require such Affiliated Stockholders to suspend the
use of the prospectus for sales of Registrable Securities under the Shelf
Registration Statement for a reasonable period of time not to exceed sixty (60)
days in succession or ninety (90) days in the aggregate in any twelve (12) month
period (a "SUSPENSION PERIOD") if the Company shall determine that it is
required to disclose in the Shelf Registration Statement a financing,
acquisition, corporate reorganization or other similar corporate transaction or
other material event or circumstance affecting the Company or its securities,
and that the disclosure of such information at such time would be detrimental to
the Company or its stockholders. Immediately upon receipt of such notice, the
Affiliated Stockholders covered by the Shelf Registration Statement shall
suspend the use of the prospectus until the requisite changes to the prospectus
have been made as required below. Any Suspension Period shall terminate at such
time as the public disclosure of such information is made. After the expiration
of any Suspension Period and without any further request from an Affiliated


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Stockholder, the Company shall as promptly as reasonably practicable prepare
a post-effective amendment or supplement to the Shelf Registration Statement
or the prospectus, or any document incorporated therein by reference, or file
any other required document so that, as thereafter delivered to purchasers of
the Registrable Securities included therein, the prospectus will not include
an untrue statement of a material fact or omit to state any material fact
necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading.

            Section 1.4 WITHDRAWAL RIGHTS. Any Affiliated Stockholder having
notified or directed the Company to include any or all of its Registrable
Securities in a registration statement under the Securities Act shall have the
right to withdraw any such notice or direction with respect to any or all of the
Registrable Securities designated by it for registration by giving written
notice to such effect to the Company prior to the effective date of such
registration statement. In the event of any such withdrawal, the Company shall
not include such Registrable Securities in the applicable registration and such
Registrable Securities shall continue to be Registrable Securities for all
purposes of this Agreement. No such withdrawal shall affect the obligations of
the Company with respect to the Registrable Securities not so withdrawn;
PROVIDED THAT in the case of a Demand Registration, if such withdrawal shall
reduce the number of Registrable Securities sought to be included in such
registration below the Requisite Amount, then the Company shall as promptly as
practicable give each holder of Registrable Securities sought to be registered
notice to such effect and, within ten (10) business days following the mailing
of such notice, either the Company or the holders of a majority, in number of
shares, of the Registrable Securities sought to be registered may, by written
notices made to the Company and each holder of Registrable Securities sought to
be registered, elect that such registration statement not be filed or, if
theretofore filed, be withdrawn. During such ten (10) business day period, the
Company shall not file such registration statement if not theretofore filed or,
if such registration statement has been theretofore filed, the Company shall not
seek, and shall use commercially reasonable efforts to prevent, the
effectiveness thereof. Any registration statement withdrawn or not filed (a) in
accordance with an election by the Company, (b) in accordance with an election
by the holders of the majority, in number of shares, of the Registrable
Securities sought to be registered pursuant to such Demand Registration pursuant
to Section 1.1(g) hereof, or (c) in accordance with an election by the holders
of the majority of the Registrable Securities sought to be registered pursuant
to such Demand Registration subsequent to the effectiveness of the applicable
Demand Registration Statement, if any post-effective amendment or supplement to
the applicable Demand Registration Statement contains information regarding the
Company which the Company deems adverse to the Company, shall not be counted as
a Demand. Except as set forth in clause (c) of the previous sentence, any Demand
withdrawn in accordance with an election by the Demanding Holders subsequent to
the effectiveness of the applicable Demand Registration Statement shall be
counted as a Demand unless the Demanding Holders reimburse the Company for its
reasonable out-of-pocket expenses (but, without implication that the contrary
would otherwise be true, not including any Internal Expenses, as defined in
Section 1.7 hereof) related to the preparation and filing of such registration
statement (in which event such registration statement shall not be counted as a
Demand hereunder). Upon the written request of a majority, by number of shares,
of such Demanding Holders, the Company shall promptly prepare a definitive
statement of such out-of-pocket expenses in connection with such


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registration statement in order to assist such Demanding Holders with a
determination in accordance with the next preceding sentence.

            Section 1.5 HOLDBACK AGREEMENTS. Each Affiliated Stockholder agrees
not to effect any public sale or distribution (including sales pursuant to Rule
144) of equity securities of the Company, or any securities convertible into or
exchangeable or exercisable for such securities, during the ten (10) day period
prior to and the one hundred twenty (120) day period following the date on which
the Company has notified the Affiliated Stockholders that it, or in the case of
a Demand Registration the Demanding Holders, intend to commence a Public
Offering, Demand Registration or Piggyback Registration (in each case, except as
part of such registration), or, in each case, a later date required by any
underwriting agreement with respect thereto.

            Section 1.6 REGISTRATION PROCEDURES.

            (1) REGISTRATION. If and whenever the Company is required to use
commercially reasonable efforts to effect the registration of any Registrable
Securities under the Securities Act as provided in Sections 1.1, 1.2, and 1.3
(subject to its right to withdraw such registration as contemplated by Sections
1.2(c) and 1.4) the Company shall as expeditiously as possible:

                  (1) prepare and file with the Commission a registration
statement to effect such registration and thereafter use commercially reasonable
efforts to cause such registration statement to become and remain effective,
pursuant to the terms of this agreement; PROVIDED HOWEVER that the Company may
discontinue any registration of its securities which are not Registrable
Securities (and, under the circumstances specified in Section 1.2, its
securities which are Registrable Securities) at any time prior to the effective
date of the registration statement relating thereto; PROVIDED FURTHER that
before filing such registration statement or any amendments thereto, the Company
will furnish to the counsel selected by the holders of Registrable Securities
which are to be included in such registration copies of all such documents
proposed to be filed, to the extent specifically requested by such counsel,
which documents will be subject to the review of such counsel, and such review
to be conducted with reasonable promptness;

                  (2) prepare and file with the Commission such amendments and
supplements to such registration statement and the prospectus used in connection
therewith as may be necessary to keep such registration statement effective and
to comply with the provisions of the Securities Act with respect to the
disposition of all securities covered by such registration statement until the
earlier of such time as all of such securities have been disposed of in
accordance with the intended methods of disposition by the seller or sellers
thereof set forth in such registration statement or (i) in the case of a
registration pursuant to Section 1.1, the expiration of sixty (60) days after
such registration statement becomes effective, or (ii) in the case of a
registration pursuant to Section 1.2, the expiration of sixty (60) days after
such registration statement becomes effective or (iii) in the case of a
registration pursuant to Section 1.3, the expiration of one (1) year after such
registration statement becomes effective;


                                       8

<Page>


                  (3) furnish to each seller of Registrable Securities covered
by such registration statement and each underwriter, if any, of the securities
being sold by such seller such number of conformed copies of such registration
statement and of each amendment and supplement thereto (in each case including
all exhibits), such number of copies of the prospectus contained in such
registration statement (including each preliminary prospectus and any summary
prospectus) and any other prospectus filed under Rule 424 under the Securities
Act, in conformity with the requirements of the Securities Act, and such other
documents as such seller and underwriter, if any, may reasonably request in
order to facilitate the public sale or other disposition of the Registrable
Securities owned by such seller;

                  (4) use commercially reasonable efforts to register or qualify
such Registrable Securities covered by such registration statement under such
other securities laws or blue sky laws of such jurisdictions as any seller
thereof and any underwriter of the securities being sold by such seller shall
reasonably request, and take any other action which may be reasonably necessary
or advisable to enable such seller and underwriter to consummate the disposition
in such jurisdictions of the Registrable Securities owned by such seller, except
that the Company shall not for any such purpose be required to qualify generally
to do business as a foreign corporation in any jurisdiction wherein it would not
but for the requirements of this subdivision (iv) be obligated to be so
qualified, to subject itself to taxation in any such jurisdiction or to file a
general consent to service of process in any such jurisdiction;

                  (5) use commercially reasonable efforts to cause such
Registrable Securities covered by such registration statement to be registered
with or approved by such other governmental agencies or authorities as may be
necessary to enable the seller or sellers thereof to consummate the disposition
of such Registrable Securities;

                  (6) in connection with an underwritten offering, obtain for
each seller of Registrable Securities and underwriter:

                              (1)   an opinion of counsel for the
      Company, covering the matters customarily covered in opinions requested in
      underwritten offerings and such other matters as may be reasonably
      requested by such sellers and underwriters, and

                              (2)   a "comfort" letter (or, in the case
      of any such Person which does not satisfy the conditions for receipt of a
      "comfort" letter specified in Statement on Auditing Standards No. 72, an
      "agreed upon procedures" letter) signed by the independent public
      accountants who have certified the Company's financial statements included
      in such registration statement, covering substantially the same matters as
      are customarily covered in opinions of issuer's counsel delivered to the
      underwriters in underwritten public offerings of securities;

                  (7) promptly notify the holders of Registrable Securities and
the underwriters, if any, of the following events and, if requested by any such
holder or underwriter, confirm such notification in writing:



                                       9

<Page>


                              (1)   the filing of the registration
      statement, the prospectus or any prospectus supplement related thereto or
      post-effective amendment to the registration statement, and, with respect
      to the registration statement or any post-effective amendment thereto,
      when the same has become effective;

                              (2)   any request by the Commission for
      amendments or supplements to the registration statement or the
      prospectus or for additional information;

                              (3)   the issuance by the Commission of
      any stop order suspending the effectiveness of the registration
      statement or the initiation of any proceedings by any Person for
      that purpose; and

                              (4)   the receipt by the Company of any
      notification with respect to the suspension of the qualification of any
      Registrable Securities for sale under the securities or blue sky laws of
      any jurisdiction or the initiation or threat of any proceeding for such
      purpose;

                  (8) notify each seller of Registrable Securities covered by
such registration statement, at any time when a prospectus relating thereto is
required to be delivered under the Securities Act, upon discovery that, or upon
the happening of any event as a result of which, the prospectus included in such
registration statement, as then in effect, includes an untrue statement of a
material fact or omits to state any material fact required to be stated therein
or necessary to make the statements therein not misleading in the light of the
circumstances then existing, and, at the request of any such seller, promptly
prepare and furnish to such seller a reasonable number of copies of a supplement
to or an amendment of such prospectus as may be necessary so that, as thereafter
delivered to the purchasers of such Registrable Securities, such prospectus
shall not include an untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading in the light of the circumstances then existing;

                  (9)   make every commercially reasonable effort to obtain
the withdrawal of any order suspending the effectiveness of the registration
statement;

                  (10) otherwise use commercially reasonable efforts to comply
with all applicable rules and regulations of the Commission, and make available
to holders of Registrable Securities, as soon as reasonably practicable, an
earnings statement covering the period of at least twelve months, but not more
than eighteen months, beginning with the first day of the Company's first full
quarter after the effective date of such registration statement, which earnings
statement shall satisfy the provisions of Section 11(a) of the Securities Act
and Rule 158 thereunder.

            The Company may require each seller of Registrable Securities as to
which any registration is being effected and each underwriter, if any, to
furnish the Company in writing such information regarding each seller or
underwriter and the distribution of such Registrable


                                       10

<Page>

Securities as the Company may from time to time reasonably request to
complete or amend the information required by the registration statement.

            (2) UNDERWRITING. Without limiting any of the foregoing, in the
event that the offering of Registrable Securities is to be made by or through an
underwriter, the Company shall enter into an underwriting agreement with a
managing underwriter or underwriters containing representations, warranties,
indemnities and agreements customarily included (but not inconsistent with the
agreements contained herein) by an issuer of common stock in underwriting
agreements with respect to offerings of common stock for the account of, or on
behalf of, such issuers. In connection with any offering of Registrable
Securities registered pursuant to this Agreement, the Company shall (i) furnish
to the underwriter, if any (or, if no underwriter, the sellers of such
Registrable Securities), unlegended certificates representing ownership of the
Registrable Securities being sold, in such denominations as requested and (ii)
instruct any transfer agent and registrar of the Registrable Securities to
release any stop transfer order with respect thereto.

            (3) RETURN OF PROSPECTUSES. Each seller of Registrable Securities
hereunder agrees that upon receipt of any notice from the Company of the
happening of any event of the kind described in Section 1.6(a)(viii), such
seller shall forthwith discontinue such seller's disposition of Registrable
Securities pursuant to the applicable registration statement and prospectus
relating thereto until such seller's receipt of the copies of the supplemented
or amended prospectus contemplated by Section 1.6(a)(viii) and, if so directed
by the Company, deliver to the Company, at the Company's expense, all copies,
other than permanent file copies, then in such seller's possession of the
prospectus current at the time of receipt of such notice relating to such
Registrable Securities. In the event the Company shall give such notice, any
applicable sixty (60) day period during which such registration statement must
remain effective pursuant to this Agreement shall be extended by the number of
days during the period from the date of giving of a notice regarding the
happening of an event of the kind described in Section 1.6(a)(viii) to the date
when all such sellers shall receive such a supplemented or amended prospectus
and such prospectus shall have been filed with the Commission.

            Section 1.7 REGISTRATION EXPENSES. All expenses incident to the
Company's performance of, or compliance with, its obligations under this
Agreement including, without limitation, all registration and filing fees, all
fees and expenses of compliance with securities and "blue sky" laws, all
printing and copying expenses, all messenger and delivery expenses, all fees and
expenses of the Company's independent certified public accountants and counsel
(including, without limitation, with respect to "comfort" letters and opinions)
(collectively, the "REGISTRATION EXPENSES") shall be borne by the Company. The
Company will pay its internal expenses (including, without limitation, all
salaries and expenses of its officers and employees performing legal or
accounting duties, the expense of any annual audit and the expense of any
liability insurance) (collectively, "INTERNAL EXPENSES") and the expenses and
fees for listing the securities to be registered on each securities exchange and
included in each established over-the-counter market on which similar securities
issued by the Company are then listed or traded.

            Section 1.8 INDEMNIFICATION.


                                       11

<Page>


            (1) BY THE COMPANY. The Company agrees to indemnify and hold
harmless, to the fullest extent permitted by law, each holder of Registrable
Securities being sold, its officers, directors, employees, managers and agents
and each Person who controls (within the meaning of the Securities Act) such
holder or such other indemnified Person from and against all losses, claims,
damages, liabilities and expenses (collectively, the "LOSSES") caused by,
resulting from or relating to any untrue or alleged untrue statement of a
material fact contained in any registration statement, prospectus or preliminary
prospectus or any amendment thereof or supplement thereto or any omission or
alleged omission of a material fact required to be stated therein or necessary
to make the statements therein, in light of the circumstances under which they
were made, not misleading, EXCEPT insofar as the same are caused by any
information furnished in writing to the Company by such holder expressly for use
therein OR by such holder's failure to deliver a copy of a current prospectus or
any amendments or supplements thereto (which does not contain any such material
misstatements or omissions) after the Company has furnished such holder with a
sufficient number of copies of the same. In connection with an underwritten
offering and without limiting any of the Company's other obligations under this
Agreement, the Company shall indemnify such underwriters, their officers,
directors, employees and agents and each Person who controls (within the meaning
of the Securities Act) such underwriters or such other indemnified Person to the
same extent as provided above with respect to the indemnification (and
exceptions thereto) of the holders of Registrable Securities being sold.

            (2) BY THE STOCKHOLDERS. In connection with any registration
statement in which a holder of Registrable Securities is participating, each
such holder will furnish to the Company in writing information regarding such
holder's ownership of Registrable Securities and its intended method of
distribution thereof and, to the extent permitted by law, shall, severally and
not jointly, indemnify the Company, its directors, officers, employees and
agents and each Person who controls (within the meaning of the Securities Act)
the Company or such other indemnified Person against all Losses caused by any
untrue or alleged untrue statement of material fact contained in the
registration statement, prospectus or preliminary prospectus or any amendment
thereof or supplement thereto or any omission or alleged omission of a material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances under which they were made, not misleading, but
only to the extent that such untrue statement or omission is caused by and
contained in such information so furnished in writing by such holder expressly
for use therein; PROVIDED, HOWEVER, that each holder's obligation to indemnify
the Company hereunder shall, to the extent more than one holder is subject to
the same indemnification obligation, be apportioned between each holder based
upon the net amount received by each holder from the sale of Registrable
Securities, as compared to the total net amount received by all of the holders
of Registrable Securities sold pursuant to such registration statement.
Notwithstanding the foregoing, no holder shall be liable to the Company for
amounts in excess of the lesser of (i) such apportionment and (ii) the amount
received by such holder in the offering giving rise to such liability.

            (3) NOTICE. Any Person entitled to indemnification hereunder shall
give prompt written notice to the indemnifying party of any claim with respect
to which its seeks indemnification; PROVIDED, HOWEVER, the failure to give such
notice shall not release the indemnifying party from its obligation, except to
the extent that the indemnifying party has been materially prejudiced by such
failure to provide such notice on a timely basis.


                                       12

<Page>


            (4) DEFENSE OF ACTIONS. In any case in which any such action is
brought against any indemnified party, and it notifies an indemnifying party of
the commencement thereof, the indemnifying party will be entitled to participate
therein, and, to the extent that it may wish, jointly with any other
indemnifying party similarly notified, to assume the defense thereof, with
counsel reasonably satisfactory to such indemnified party, and after notice from
the indemnifying party to such indemnified party of its election so to assume
the defense thereof, the indemnifying party will not (so long as it shall
continue to have the right to defend, contest, litigate and settle the matter in
question in accordance with this paragraph) be liable to such indemnified party
hereunder for any legal or other expense subsequently incurred by such
indemnified party in connection with the defense thereof other than reasonable
costs of investigation, supervision and monitoring (unless (i) such indemnified
party reasonably objects to such assumption on the grounds that there may be
defenses available to it which are different from or in addition to the defenses
available to such indemnifying party or (ii) the indemnifying party shall have
failed within a reasonable period of time to assume such defense and the
indemnified party is or is reasonably likely to be prejudiced by such
unreasonable delay, in either event the indemnified party shall be reimbursed by
the indemnifying party for the expenses incurred in connection with retaining
separate legal counsel). An indemnifying party shall not be liable for any
settlement of an action or claim effected without its consent. The indemnifying
party shall lose its right to defend, contest, litigate and settle a matter if
it shall fail to diligently contest such matter (except to the extent settled in
accordance with the next following sentence). No matter shall be settled by an
indemnifying party without the consent of the indemnified party (which consent
shall not be unreasonably withheld).

            (5) SURVIVAL. The indemnification provided for under this Agreement
shall remain in full force and effect regardless of any investigation made by or
on behalf of the indemnified Person and will survive the transfer of the
Registrable Securities and the termination of this Agreement.

            (6) CONTRIBUTION. If recovery is not available under the foregoing
indemnification provisions for any reason or reasons other than as specified
therein, any Person who would otherwise be entitled to indemnification by the
terms thereof shall nevertheless be entitled to contribution with respect to any
Losses with respect to which such Person would be entitled to such
indemnification but for such reason or reasons. In determining the amount of
contribution to which the respective Persons are entitled, there shall be
considered the Persons' relative knowledge and access to information concerning
the matter with respect to which the claim was asserted, the opportunity to
correct and prevent any statement or omission, and other equitable
considerations appropriate under the circumstances. It is hereby agreed that it
would not necessarily be equitable if the amount of such contribution were
determined by PRO RATA or PER CAPITA allocation. No person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any person who was not found guilty of
such fraudulent misrepresentation. Notwithstanding the foregoing, no Affiliated
Stockholder shall be required to make a contribution in excess of the net amount
received by such holder from its sale of Registrable Securities in connection
with the offering that gave rise to the contribution obligation.


                                       13

<Page>


            Section 1.9 RESTRICTIONS ON TRANSFER. Prior to any transfer of any
Registrable Securities which are not registered under an effective registration
statement under the Securities Act, the holder thereof will give written notice
to the Company of such holder's intention to effect such transfer and to comply
in all other respects with this Section 1.9. Each such notice (a) shall describe
the manner and circumstances of the proposed transfer in sufficient detail to
enable counsel to render the opinions referred to below, and (b) shall designate
counsel for the holder giving such notice. The holder giving such notice will
submit a copy thereof to the counsel designated in such notice and the Company
will promptly submit a copy thereof to its counsel. The following provisions
shall then apply:

                  (1) If (A) in the opinion of such counsel for the holder the
proposed transfer may be effected without registration of such Registrable
Securities under the Securities Act, and (B) counsel for the Company shall not
have rendered an opinion within twenty (20) days after receipt by the Company of
such written notice that such registration is required, such holder shall
thereupon be entitled to transfer such Registrable Securities in accordance with
the terms of the notice delivered by such holder to the Company; and

                  (2) If in the opinion of either or both of such counsel the
proposed transfer may not legally be effected without registration of such
Registrable Securities under the Securities Act (such opinion or opinions to
state the basis of the legal conclusions reached therein), the Company will
promptly so notify the holder thereof and thereafter such holder shall not be
entitled to transfer such Registrable Securities until receipt of a further
notice from the Company under clause (i) above or until registration of such
Registrable Securities under the Securities Act has become effective.

            Notwithstanding the foregoing provisions of this Section 1.9, the
purchaser of the Common Stock shall be permitted to transfer any Registrable
Securities to a limited number of institutional investors, PROVIDED that (A)
each such investor represents in writing that it is acquiring such Registrable
Securities for investment and not with a view to the distribution thereof
(subject, however, to any requirement of law that the disposition thereof shall
at all times be within the control of such transferee), (B) each such investor
agrees in writing to be bound by all the restrictions on transfer of such
Registrable Securities contained in this Section 1.9 and (C) the purchaser of
the Common Stock delivers to the Company an opinion of counsel satisfactory to
the Company, stating that such transfer may be effected without registration
under the Securities Act.

                                   ARTICLE II

                                  MISCELLANEOUS

            Section 1.10 HEADINGS. The headings in this Agreement are for
convenience of reference only and shall not control or affect the meaning or
construction of any provisions hereof.

            Section 1.11 ENTIRE AGREEMENT. This Agreement constitutes the entire
agreement and understanding of the parties hereto in respect of the subject
matter contained herein, and there are no restrictions, promises,
representations, warranties, covenants, conditions or undertakings with respect
to the subject matter hereof, other than those expressly set forth or referred
to herein. This Agreement supersedes all prior agreements and understandings
between the parties hereto with respect to the subject matter hereof.

            Section 1.12 TERMINATION OF CERTAIN RIGHTS. The rights and
obligations hereunder of each Affiliated Stockholder will terminate with respect
to such Affiliated Stockholder at such time when it is no longer an Affiliated
Stockholder under this Agreement; PROVIDED, HOWEVER, that the provisions of
Section 1.6 hereof, the rights of any Affiliated



                                       14

<Page>

Stockholder with respect to breach of any provision hereof, and any
obligation accrued as of the date of termination shall survive termination of
this Agreement.

            Section 1.13 RULE 144. The Company covenants that, after such time
it has prepared and filed with the Commission its Report on Form 10-K for the
fiscal year ended December 1, 2000 and its Reports on Form 10-Q for the
quarterly periods ended March 2, 2001, June 1, 2001 and August 31, 2001, it will
file the reports required to be filed by it under the Securities Act and the
Exchange Act and the rules and regulations adopted by the Commission thereunder
(or, if it is not required to file such reports, it will, upon the request of
any holder of Registrable Securities, make publicly available other information
so long as necessary to permit sales pursuant to Rule 144 under the Securities
Act), and it will take such further commercially reasonable action, to the
extent required from time to time to enable such holder to sell Registrable
Securities without registration under the Securities Act within the limitation
of the exemptions provided by Rule 144 under the Securities Act, as such Rule
may be amended from time to time, or any similar rule or regulation hereafter
adopted by the Commission. Upon the reasonable request of any holder of
Registrable Securities, the Company will deliver to such holder a written
statement as to whether it has complied with such information and filing
requirements.

            Section 1.14 NOTICES. All notices and other communications hereunder
shall be in writing and shall be delivered personally or by next-day courier or
telecopied with confirmation of receipt, at the address or telecopier number
specified below (or at such other address or number for a party as shall be
specified by like notice; PROVIDED that notices of change of address shall be
effective only upon receipt thereof). Any such notice shall be effective upon
receipt, if personally delivered, upon being sent and confirmed if telecopied,
or one business day after delivery to a courier for next-day delivery.

                  If to Company:

                        Washington Group International, Inc.
                        720 Park Boulevard
                        Boise, Idaho 83712
                        Attention: Richard D. Parry
                        Facsimile: 208.386.5220

                  with a copy to:

                        Jones, Day, Reavis & Pogue
                        77 West Wacker Drive
                        Chicago, Illinois 60601
                        Attention: Robert Dean Avery
                        Facsimile: 312.782.8585


                                       15

<Page>


                  If to Stockholders:

                        At the addresses and telecopier
                        and confirmation numbers listed
                        on the signature pages hereto.

            Section 1.15 APPLICABLE LAW. The substantive laws of the State of
New York shall govern the interpretation, validity and performance of the terms
of this Agreement, without regard to conflicts of laws doctrines. THE PARTIES
HERETO WAIVE THEIR RIGHT TO A JURY TRIAL WITH RESPECT TO DISPUTES HEREUNDER.

            Section 1.16 SEVERABILITY. The invalidity, illegality or
unenforceability of one or more of the provisions of this Agreement in any
jurisdiction shall not affect the validity, legality or enforceability of the
remainder of this Agreement in such jurisdiction or the validity, legality or
enforceability of this Agreement, including any such provision, in any other
jurisdiction, it being intended that all rights and obligations of the parties
hereunder shall be enforceable to the fullest extent permitted by law.

            Section 1.17 SUCCESSORS; ASSIGNS. The provisions of this Agreement
shall be binding upon the parties hereto and their respective heirs, successors
and assigns whether so expressed or not. In addition, whether or not any express
assignment has been made, the provisions of this Agreement which are for the
benefit of purchasers or holders of Registrable Securities are also for the
benefit of, and enforceable by, any subsequent holder of Registrable Securities
which, in a written instrument delivered to the Company at the time such person
became a holder of Registrable Securities, agrees to be bound by the provisions
of this Agreement.

            Section 1.18 AMENDMENTS. This Agreement may not be amended, modified
or supplemented unless such amendment, modification or supplement is in writing
and signed by the Company and the holders of at least 60% of the Registrable
Securities outstanding on the date thereof (and, in the case of any amendment,
modification or supplement that materially adversely affects any particular
Affiliated Stockholder or group of Affiliated Stockholders, with the written
consent of such Affiliated Stockholder or group of Affiliated Stockholders).

            Section 1.19 WAIVER. Any waiver (express or implied) of any default
or breach of this Agreement shall not constitute a waiver of any other or
subsequent default or breach.

            Section 1.20 COUNTERPARTS. This Agreement may be executed in two or
more counterparts, each of which shall be deemed an original but all of which
shall constitute one and the same Agreement.

            Section 1.21 SUBMISSION TO JURISDICTION. ANY LEGAL ACTION OR
PROCEEDING WITH RESPECT TO THIS AGREEMENT MAY BE BROUGHT IN THE COURTS OF THE
STATE OF NEW YORK OR OF THE UNITED STATES OF AMERICA FOR THE SOUTHERN DISTRICT
OF NEW YORK, AND, BY EXECUTION AND DELIVERY OF THIS AGREEMENT, THE COMPANY
HEREBY ACCEPTS FOR ITSELF


                                       16

<Page>

AND IN RESPECT OF ITS PROPERTY, GENERALLY AND UNCONDITIONALLY, THE
JURISDICTION OF THE AFORESAID COURTS AND APPELLATE COURTS FROM ANY THEREOF.
EACH PARTY HERETO HEREBY IRREVOCABLY CONSENTS TO THE SERVICE OF PROCESS OUT
OF ANY OF THE AFOREMENTIONED COURTS IN ANY ACTION OR PROCEEDING BY THE
MAILING OF COPIES THEREOF TO SUCH PARTY BY REGISTERED OR CERTIFIED MAIL TO
SUCH PARTY AT ITS ADDRESS SPECIFIED IN THIS ARTICLE 3. THE PARTIES HERETO
HEREBY IRREVOCABLY WAIVE ANY OBJECTION TO THE LAYING OF VENUE OR BASED ON THE
GROUNDS OF FORUM NON CONVENIENS, WHICH IT MAY NOW OR HEREAFTER HAVE TO THE
BRINGING OF ANY SUCH ACTION OR PROCEEDING IN SUCH RESPECTIVE JURISDICTIONS.

                                   ARTICLE III

                                   DEFINITIONS

            For purposes of this Agreement, the following terms shall have the
following meanings:

            (1) "AFFILIATE" shall have the meaning set forth in Rule 405
promulgated under the Securities Act.

            (2)   "AFFILIATED STOCKHOLDERS"  shall have the meaning set forth
in the Preamble hereof.

            (3)   "BOARD" shall man the board of directors of the Company.

            (4) "COMMISSION" shall mean the United States Securities and
Exchange Commission or any successor agency.

            (5)   "COMMON STOCK" shall have the meaning set forth in the
Preamble hereof.

            (6)   "COMPANY" shall have the meaning set forth in the Preamble
hereof.

            (7)   "DEMAND" shall have the meaning set forth in Section 1.1(a)
hereof.

            (8) "DEMAND REGISTRATION" shall have the meaning set forth in
Section 1.1(a) hereof.

            (9) "DEMANDING HOLDER" shall have the meaning set forth in Section
1.1(b) hereof.

            (10)  "EFFECTIVE DATE" shall have the meaning set forth in the
Preamble hereof.

            (11) "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934,
as amended, and the rules and regulations promulgated thereunder.


                                       17

<Page>


            (12) "FORM S-3" shall have the meaning set forth in Section 1.3(a)
hereof.

            (13) "INTERNAL EXPENSES" shall have the meaning set forth in Section
1.7 hereof.

            (14)  "LOSSES" shall have the meaning set forth in Section 1.8(a)
hereof.

            (15) "MARKET PRICE" of publicly traded shares of Common Stock or any
other class of capital stock or other security of the Company or any other
issuer for any trading day shall mean the last reported sales price, regular way
on such day, or, if no sale takes place on such day, the average of the reported
closing bid and asked prices on such day, regular way, in either case as
reported on the securities exchange in which the Common Stock is listed for
trading, or, if not listed or admitted for trading on any securities exchange,
the average of the closing bid and asked prices on such day in the
over-the-counter market as reported by The Nasdaq National Market or any
comparable system, or if the common stock is not included for quotation in The
Nasdaq National Market or a comparable system, Market Price shall be determined
reasonably and in good faith by the Board or in such manner as shall be
reasonably established by the Board.

            (16) "MAXIMUM DEMAND NUMBER" shall have the meaning set forth in
Section 1.1(h) hereof.

            (17) "MAXIMUM PIGGYBACK NUMBER" shall have the meaning set forth in
Section 1.2(b) hereof.

            (18) "OTHER DEMAND RIGHTS" shall have the meaning set forth in
Section 1.2(b) hereof.

            (19) "OTHER DEMANDING SELLERS" shall have the meaning set forth in
Section 1.2(b) hereof.

            (20) "PERSON" shall mean any individual, firm, corporation,
partnership, limited liability company or other entity, and shall include any
successor (by merger or otherwise) of such entity.

            (21) "PIGGYBACK NOTICE" shall have the meaning set forth in Section
1.2(a) hereof.

            (22) "PIGGYBACK REGISTRATION" shall have the meaning set forth in
Section 1.2(a) hereof.

            (23) "PIGGYBACK SELLERS" shall have the meaning set forth in Section
1.2(b) hereof.

            (24)  "PLAN" shall have the meaning set forth in the Preamble
hereof.


                                       18

<Page>


            (25) "PRIMARY OFFERING" shall have the meaning set forth in Section
1.2(b)(i) hereof.

            (26) "PUBLIC OFFERING" shall mean a public offering of equity
securities of the Company pursuant to an effective registration statement under
the Securities Act, including a public offering in which Affiliated Stockholders
are entitled to sell Common Stock pursuant to the terms of this Agreement.

            (27) "REGISTRABLE SECURITIES" shall mean (i) any Common Stock issued
to the Affiliated Stockholders pursuant to the Plan, and (ii) any Common Stock
issued or issuable with respect to the securities referred to in clause (i) by
way of stock dividend or stock split or in connection with a combination of
shares, recapitalization, merger, consolidation, or other reorganization. As to
any particular Registrable Securities, such securities shall cease to be
Registrable Securities when (x) a registration statement registering such
securities under the Securities Act has been declared effective and such
securities have been sold or otherwise transferred by the holder thereof
pursuant to such effective registration statement; or (y) such securities are
sold in accordance with Rule 144 (or any successor provision) promulgated under
the Securities Act.

            (28) "REGISTRATION EXPENSES" shall have the meaning set forth in
Section 1.7 hereof.

            (29) "REQUISITE AMOUNT" shall mean 15% of the Registrable Securities
outstanding at any given time.

            (30) "SECURITIES ACT" shall mean the Securities Act of 1933, as
amended, and the rules and regulations promulgated thereunder.


                                       19

<Page>


            (31) "SHELF NOTICE" shall have the meaning set forth in Section
1.3(a) hereof.

            (32) "SHELF REGISTRATION STATEMENT" shall have the meaning set forth
in Section 1.3(a) hereof.

            (33) "SUSPENSION PERIOD" shall have the meaning set forth in Section
1.3(d) hereof.



                                       20

<Page>



            IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed and delivered by their respective officers thereunto duly authorized as
of the date first above written.

                        WASHINGTON GROUP INTERNATIONAL, INC.


                        By:    /s/   Richard D. Parry
                               -----------------------------------
                        Name:  Richard D. Parry
                        Title: Sr. Vice President & General Counsel



AFFILIATED STOCKHOLDERS:

                        CREDIT SUISSE FIRST BOSTON
                        Name:
                        Address:
                        Attention:
                        Telephone:
                        Facsimile:

                        By:    /s/ Robert Hetu
                               -----------------------------------
                        Name:  Robert Hetu
                        Title: Director

                        By:    /s/ John D. Lewis
                               -----------------------------------
                        Name:  John D. Lewis
                        Title: Associate


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