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                                                             Exhibit No. 4(a)(7)

     THIS SEVENTH SUPPLEMENTAL INDENTURE, dated as of August 13, 1998, is
entered into by and among ICF KAISER INTERNATIONAL, INC., a Delaware corporation
(the "Company"), THE BANK OF NEW YORK, a New York banking corporation (the
"Trustee"), the following existing GUARANTORS:

     Cygna Consulting Engineers and Project Management, Inc., a Delaware
     corporation ("Cygna");
     ICF Kaiser Government Programs, Inc., a Delaware corporation ("ICFK-GP");
     Systems Applications International, Inc., a Delaware corporation "(SAI")
     EDA, Incorporated, a Maryland corporation ("EDA");
     Global Trade & Investment, Inc., a Delaware corporation ("Global");
     ICF Kaiser Europe, Inc., a Delaware corporation ("ICFK Europe");
     ICF Kaiser / Georgia Wilson, Inc., a Delaware corporation ("ICFK/GW");
     ICF Kaiser Overseas Engineering, Inc., a Delaware corporation ("ICFK
     Overseas");
     ICF Kaiser Engineers Pacific, Inc., a Delaware corporation ("ICFK
     Pacific"); and
     ICF Kaiser Remediation Company, a Delaware corporation ("Remcon")

and the following new GUARANTOR:

     ICF Kaiser Advanced Technology, Inc., an Idaho Corporation ("Advanced
     Tech").

                                 WITNESSETH:

     WHEREAS, the new Guarantor is an indirect Wholly Owned Restricted
Subsidiary of the Company;

     WHEREAS, on December 3, 1997, the Company entered into an Amended and
Restated Credit Agreement with First Union Capital Markets, a division of Wheat
First Securities, Inc. ("First Union"), as Agent, the banking institutions named
therein (the "Banks"), and certain subsidiaries of the Company named therein
(the "Subsidiary Guarantors"), as a successor Bank Credit Agreement;

     WHEREAS, as a condition to the Company's being permitted to include the
Accounts Receivable of the new Guarantor in the Borrowing Base as defined in and
provided for under the Bank Credit Agreement, the new Guarantor must become a
Subsidiary Guarantor under the Bank Credit Agreement;

     WHEREAS, Advance Tech has determined that it is desirable to become
Subsidiary Guarantor under the Bank Credit Agreement;

     WHEREAS, the Company and the Trustee have heretofore executed and delivered
an Indenture dated as of January 11, 1994 (the "Indenture"), for the purpose of
issuing $125,000,000 of 12% Senior Subordinated Notes due 2003, (the "Notes"),
and Section 10.01 of the Indenture provides that the Company (when authorized by
a Board Resolution) and the Trustee for the Notes, at any time and from time to
time, may enter into one or more indentures supplemental thereto, in form
satisfactory to such Trustee, for any of the purposes set forth in said Section
10.01 (each a "Supplemental Indenture");

     WHEREAS, Section 5.11 of the Indenture requires that, prior to or
concurrently with the new Guarantor becoming a Subsidiary Guarantor under the
Bank Credit Agreement, the Company must cause the new Guarantor to execute and
deliver to the Trustee a Supplemental Indenture and a Indenture Guarantee
(substantially in the form attached as Exhibit G to the Indenture) pursuant to
which the new Guarantor will unconditionally guarantee the payment of principal
of, premium, if any, and interest on the Notes;
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  WHEREAS, ICFK-GP, Cygna, and SAI became Subsidiary Guarantors under the Bank
Credit Agreement in 1996;

  WHEREAS, EDA, Global, ICFK Europe, ICFK/GW, ICFK Overseas, ICFK Pacific, and
Remcon, became Subsidiary Guarantors under the Bank Credit Agreement in 1997;

  WHEREAS, Advanced Tech will become a Subsidiary Guarantor under the Bank
Credit Agreement on August 13, 1998, and has determined that it is desirable
simultaneously or concurrently to become a new Guarantor under the Indenture;

  WHEREAS, the execution and delivery of this Seventh Supplemental Indenture has
been duly authorized by the Finance Committee of the Board of Directors of the
Company on August 13, 1998;

  WHEREAS, the execution and delivery of this Seventh Supplemental Indenture and
the Indenture Guarantee has been duly authorized by the Board of Directors of
the new Guarantor as of August 12, 1998;

  WHEREAS, the Company and the Guarantors have determined that it is desirable
to enter into this Seventh Supplemental Indenture and have requested the Trustee
to join with them in the execution of this Seventh Supplemental Indenture; and

  WHEREAS, the Trustee has accepted the trusts created by this Seventh
Supplemental Indenture and in evidence thereof has joined in the execution
hereof;

  NOW, THEREFORE, THIS SEVENTH SUPPLEMENTAL INDENTURE WITNESSETH, that, in
consideration of the premises and of acceptance by the Trustee of the trusts
created hereby and by the Indenture, and also for and in consideration of the
sum of One Dollar to the Company duly paid by the Trustee at or before the
execution and delivery of this Supplemental Indenture, the receipt of which is
hereby acknowledged, IT IS HEREBY COVENANTED AND AGREED, by and among the
Company, the existing and new Guarantors, and the Trustee, as follows:

  1.  Terms defined in the Indenture are used herein as therein defined.

  2.  Advanced Tech hereby acknowledges its execution and delivery of an
Indenture Guarantee dated as of August 13, 1998, in the form authorized by and
attached as Exhibit G to the Indenture.

  3.  The following sundry provisions shall be a part of this Seventh
Supplemental Indenture:

  Section 4.01.  Effect of Supplemental Indenture.  Upon the execution and
delivery of this Seventh Supplemental Indenture by the Company and the Trustee,
the Indenture shall be supplemented in accordance herewith, and this Seventh
Supplemental Indenture shall form a part of the Indenture for all purposes, and
every Holder of Notes heretofore or hereafter authenticated and delivered under
the Indenture shall be bound thereby.

  Section 4.02.  Indenture Remains in Full Force and Effect.  Except as
supplemented hereby and by the First Supplemental Indenture, all provisions in
the Indenture shall remain in full force and effect.

  Section 4.03.  Indenture and Supplemental Indentures Construed Together.  This
Seventh Supplemental Indenture is an Indenture supplemental to and in
implementation of the Indenture, and the Indenture and all Supplemental
Indentures shall henceforth be read and construed together.

                                                                          Page 2
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  Section 4.04. Confirmation and Preservation of Indenture.  The Indenture as
supplemented by the First through Sixth Supplemental Indentures is in all
respects confirmed and preserved.

  Section 4.05  Conflict with Trust Indenture Act.  If any provision of this
Seventh Supplemental Indenture limits, qualifies, or conflicts with any
provision of the Trust Indenture Act that is required under such Act to be part
of and govern any provision of this Seventh Supplemental Indenture, the
provision of such Act shall control.  If any provision of this Seventh
Supplemental Indenture modifies or excludes any provision of the Trust Indenture
Act that may be so modified or excluded, the provision of such Act shall be
deemed to apply to the Indenture as so modified or to be excluded by this
Seventh Supplemental Indenture, as the case may be.

  Section 4.06  Separability Clause.  In case any provision in this Seventh
Supplemental Indenture shall be invalid, illegal, or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.

  Section 4.07  Terms Defined in the Indenture.  All capitalized terms not
otherwise defined herein shall have the meanings ascribed to them in the
Indenture.

  Section 4.08  Effect of Headings.  The Article and Section headings herein are
for convenience only and shall not affect the construction hereof.

  Section 4.09  Benefits of Seventh Supplemental Indenture, etc.  Nothing in
this Seventh Supplemental Indenture, the Indenture, or the Notes, express or
implied, shall give to any Person, other than the parties hereto and thereto and
their successors hereunder and thereunder and the Holders of the Notes, any
benefit of any legal or equitable right, remedy, or claim under the Indenture,
the First through Seventh Supplemental Indentures, or the Notes.

  Section 4.10  Successors and Assigns.  All covenants and agreements in this
Seventh Supplemental Indenture by the Company and the Guarantors shall bind
their successors and assigns, whether so expressed or not.

  Section 4.11  Trustee Not Responsible for Recitals.  The recitals contained
herein shall be taken as the statements of the Company and the Guarantors, and
the Trustee assumes no responsibility for their correctness.

  Section 4.12  Certain Duties and Responsibilities of the Trustee.  In entering
into this Seventh Supplemental Indenture, the Trustee shall be entitled to the
benefit of every provision of the Indenture relating to the conduct or affecting
the liability of or affording protection to the Trustee, whether or not
elsewhere herein so provided.

  Section 4.13  Governing Law.  This Seventh Supplemental Indenture shall be
governed by and construed in accordance with the laws of the State of New York,
without regard to the conflicts of law principles thereof.

  Section 4.14  Counterparts.  This Seventh Supplemental Indenture may be
executed in counterparts, each of which, when so executed, shall be deemed to be
an original, but all such counterparts shall together constitute but one and the
same instrument.

  IN WITNESS WHEREOF, the parties hereto have caused this Seventh Supplemental
Indenture to be duly executed, and the Company, the existing and new Guarantors,
and the Trustee have caused their respective corporate seals to be hereunto
affixed and attested, all as of August 13, 1998.

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