EXHIBIT 10(iii) 16
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                     AMENDMENT NUMBER FOUR
                 IT CORPORATION RETIREMENT PLAN
                        1993 RESTATEMENT


               The IT Corporation Retirement Plan (1993 Restatement) shall
be amended to read as follows, effective as indicated below:

               A.   Section 2.35 shall be amended, effective February 1,
1997, by the addition of the following at the end thereof.

               Notwithstanding the foregoing, for purposes of 
               contributions under Section 5.1 hereof, an Eligible
               Employee's Participation Commencement Date shall
               be the date he or she is first eligible to participate
               under Section 3.1 hereof.
               
               B.   Section 3.1(c) shall be amended, effective February 1,
1997, in its entirety to read as follows:

               Each Eligible Employee who is not eligible to participate
               in the Plan as specified in Section 3.1(a) or (b), above,
               shall become eligible to participate in the Plan (i) on the
               date he completes one (1) Year of Service, or (ii) after
               January 31, 1997, his date of hire, and shall commence
               participation pursuant to Section 3.2 hereof.
               
               C.   The first sentence of Section 5.2(a) shall be amended,
effective January 1, 1997, in its entirety to read as follows.

               The amount of an individual's compensation that may be
               deferred subject to the election provided in Section 5.1
               shall be a whole percentage of the individual's 
               Compensation (while a Participant) not to exceed 10% in the
               case of Highly Compensated Employees and not to exceed 15%
               in the case of Non-Highly Compensated Employees.  
               
               D.   Section 6.1(c) shall be amended, effective February 1,
1997, in its entirety to read as follows:

               Prior to July 1, 1995, four percent (4%), and after June
               30, 1995, three percent (3%) of that Compensation (earned
               in each case after the Participant's Participation
               Commencement Date) of all eligible Participants eligible
               for an allocation pursuant to the provisions of Section
               7.1(a) of the Plan for the Plan Year with respect to which
               such allocation is to be made, reduced by any forfeitures
               applied to reduce Company Contributions in accordance with
               Section 9.5(f), which amount is to be allocated to Eligible
               Participants' Company Fixed Contribution Accounts; and

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               E.   Section 6.1(e) shall be amended, effective February 1,
1997, in its entirety to read as follows:

               A monthly matching contribution for each Participant equal
               to fifty percent (50%) of the contributions made by the
               Participant under Section 5.1 hereof for such month that
               does not exceed four percent (4%) of such Participant's
               Compensation for such month (provided the beginning of such
               month coincides with or follows the Participant's 
               Participation Commencement Date), all Participant matching
               contributions to be allocated to Participants; respective
               Company Matching Contribution Accounts.
               
               IN WITNESS WHEREOF, this instrument of amendment is
executed as of February 1, 1997.

                                        IT CORPORATION

                                        By:        /s/                   
                                           ---------------------------
                                             Anthony J. DeLuca,
                                             President & Acting 
                                             Chief Executive Officer




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