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                                                                  Exhibit 10(nn)

                        ICF KAISER INTERNATIONAL, INC.
                               9300 Lee Highway
                         Fairfax, Virginia  22031-2107

                                March 13, 1998

Mr. Michael E. Tennenbaum
Tennenbaum & Co., L.L.C.
1999 Avenue of the Stars, Suite 1010
Los Angeles, CA  90067-6022

Dear Michael:

     The purpose of this letter is to set forth the agreements we have reached
as a result of discussions over the past several days.  It will become effective
on the date of your execution of this letter (the "Effective Date").

     The Board of Directors of ICF Kaiser International, Inc. (the "Company")
will nominate, recommend and solicit proxies for your election as a director,
for a three-year term, at the 1998 annual meeting of shareholders.

     Also, the Board of Directors has acted to unconditionally and irrevocably
offer Jarrod Cohen the opportunity to join the Board at his written request at
any time between July 1, 1998 and December 31, 1998 for a term extending to the
annual meeting of shareholders in 2000, and until his successor is elected.

     For your part, you and Tennenbaum & Co., L.L.C. (the "Tennenbaum Parties")
agree as follows:

     (a) During the period commencing on the Effective Date and ending on the
earlier of (i) five years after the Effective Date and (ii) the day after the
date the Tennenbaum Parties and all of their Affiliates cease to be the
Beneficial Owners of any of the Company's voting securities ("Restricted
Securities"), the Tennenbaum Parties shall not, without the express written
consent of a majority of the directors of the Company not designated by the
Tennenbaum Parties pursuant to this Agreement, acquire, directly or indirectly,
any voting securities of the Company if, following such acquisition, such
Tennenbaum Parties, together with their Affiliates, would directly or indirectly
be the Beneficial Owners of voting securities of the Company representing in the
aggregate more than 19.5% of the total combined voting power of all issued and
outstanding securities of the Company (it being understood that this provision
shall not be violated if such Tennenbaum Parties and their Affiliates become
entitled to exercise voting power in excess of such percentage as a result of
any event or circumstance other than the acquisition by such Tennenbaum Parties
or their Affiliates of Beneficial Ownership of additional voting securities of
the Company).  The Company hereby agrees that it shall not take any action,
including without limitation, any amendment to its Shareholders Rights plan,
that would prevent the Tennenbaum Parties from acquiring additional securities
within the limitations set forth herein.

     (b) During the period (i) between the date hereof and May 1, 1998 and (ii)
that you or another person who is an Affiliate of the Tennenbaum Parties is a
member of the Board of Directors, and for a period of 90 days thereafter, the
Tennenbaum Parties shall not, without the express written consent of a majority
of the directors of the Company not designated by the Tennenbaum Parties
pursuant to this Agreement:

         (x) subject any Restricted Securities to any voting trust or voting
agreement;
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Mr. Michael E. Tennenbaum
March 13, 1998
Page 2


         (y-1)  recruit, or engage in organizing persons not nominated by the
Board of Directors to oppose the Board of Directors nominated candidates in an
election; or

         (y-2)  financially support (including contributing money, lending
money, furnishing credit or entering into any other arrangements or contracts
regarding financing) a proxy contest for Board of Directors candidates to oppose
the candidates nominated by the Board of Directors; or

         (y-3)  provide any material, non-public information gained in your
position as Director to opposing Board candidates, except as required by law,
and then only after notice to the Company.

         (z)    join a partnership, limited partnership, syndicate or other
group, or otherwise act in concert with any other person, for the purpose of
acquiring holding, voting or disposing of voting securities of the Company, or
otherwise become a "person" within the meaning of Section 13(d)(3) of the
Exchange Act (in each case other than solely with another Tennenbaum Party).

     (c) Each of the Tennenbaum Parties shall be present, in person or by proxy,
         and without further action hereby agree that they shall be deemed (to
         the extent permitted by law) to be present, at all meetings of the
         stockholders of the Company with respect to which the Tennenbaum
         Parties receive notice so that all voting securities of the Company
         owned by any of them may be counted for the purpose of determining the
         presence of a quorum at such meetings.

     (d) For purposes of this letter (i) "Affiliate" shall have the same meaning
         as Affiliate under Rule 12b-2 under the Exchange Act, and (ii)
         "Beneficial Owner" shall have the same meaning as "Beneficial Owner"
         under Rule 13d-3 under the Exchange Act, and "Beneficial Ownership"
         shall have a correlative meaning.

     The agreements set forth in paragraphs (a)-(d) above shall terminate and be
of no further effect in the event (i) you are not elected as a director of ICF
Kaiser, as contemplated herein, on or before May 30, 1998; or (ii) Jarrod Cohen
does not become a director upon his acceptance of the offer referred to above.

     The Company hereby agrees to promptly reimburse the Tennenbaum Parties for
all reasonable and necessary documented out-of-pocket expenses incurred by them
(including, but not limited to fees and disbursements of counsel) in connection
with their proposals to the Board of Directors of the Company and the potential
solicitation of proxies for the election of directors to the Company, up to a
maximum of $25,000.

     If the foregoing accurately summarizes our agreement, please sign where
indicated below.

                                       Very truly yours,

                                       ICF KAISER INTERNATIONAL, INC.

TENNENBAUM & CO., L.L.C.

Michael E. Tennenbaum, individually