EXHIBIT 10(iii) 17
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     Amendment NUMBER FIVE to IT Corporation
     Retirement Plan (1993 Restatement)
     
     The IT Corporation Retirement Plan (1993 Restatement) shall be
amended as set forth herein:

     A.     The first sentence of Section 8.2 shall be amended, effective
July 1, 1995, to read as follows:

     The Vested Interest of each Participant in his Company Fixed
     Contribution Account, Discretionary Company Contribution Account, and
     Matching Contribution Account shall be determined on the basis of the
     Participant's Years of Service, in accordance with the following
     schedule.
 
     B.     Section 7.10(e) shall be amended, effective January 1, 1997,
by the addition of the following at the end thereof:

     Notwithstanding the foregoing, Employees compensated on an hourly
     basis may, but only while still actually employed by the Company,
     choose to make a required loan repayment for a month by sending a
     check to the Company's Human Resources Department, if their income
     during such month is insufficient to cover required deductible loan
     repayments.  Failure to make such payments will result in a default
     on the loan as described above.

     C.     A new Article XX shall be added, effective January 1, 1997, to
read as follows:

                        ARTICLE XX

     SPECIAL PROVISIONS REGARDING ACCOUNTS TRANSFERRED FROM THE GRADIENT
     401(K) PROFIT-SHARING PLAN.

     Section 20.1.  In General.  The following special provisions in this
     Article XX shall be effective as of January 1, 1997, and shall apply
     under the Plan to any Eligible Employee with an account under the
     Gradient 401(k) Profit-Sharing Plan ("Gradient Plan").

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     Section 20.2.  Application of Vesting Provisions.  The vesting rules
     under Article VIII hereof shall be applied as follows.  Any Eligible
     Employee with at least three (3) Years of Service recognized under
     the Gradient Plan as of December 31, 1996, shall have a Vested
     Interest under this Plan that is at least as favorable as the
     vesting percentage they would have achieved were the vesting schedule
     under the Gradient Plan to remain in effect; provided that the
     foregoing shall be applied taking into account Section 20.03 hereof. 
     Other Eligible Employees shall be fully subject to Article VIII
     hereof for all amounts contributed to this Plan on their behalf;
     provided that in respect of amounts contributed prior to January 1,
     1997, under the Gradient Plan, they shall retain at least the same
     vested percentage as they achieved under the Gradient Plan through
     December 31, 1996, taking into account Section 20.3 hereof.

     Section 20.3.  Computation of Service.  Eligible Employees under this
     Section 20.3 shall have Years of Service computed pursuant to Section
     2.54 hereof.  However, each Eligible Employee shall automatically
     receive credit for one Year of Service for the period from his or her
     anniversary date in 1996 through December 31, 1996, without regard to
     actual Hours of Service performed.

     
     IN WITNESS WHEREOF, this instrument of Amendment is executed this
13th day of May, 1997.

                                     IT CORPORATION



                                     By:          /S/ 
                                         __________________________
                                         Anthony J. DeLuca
                                         President and Acting Chief
                                           Executive Office


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