Exhibit 10.48

                                                       ThermoRetec Corporation
                                                  9 Damonmill Square. Suite 3A
                                                        Concord, MA 01742-2851


January 31, 2000

Jeff Powell
1 Walnut Street
Acton, MA 01720




Dear Jeff:


Thermo  Electron  Corporation  announced  today a  reorganization  of the parent
company, in which certain company assets,  including those of ThermoRetec,  will
be sold. This announcement represents both a challenge and an opportunity for us
as ThermoRetec  employees.  Since your past  contributions have been integral to
the  success of our own  company,  I believe  your  continued  involvement  with
ThermoRetec  will be  necessary  to  facilitate  the sale of our business and to
assure a smooth transition for a potential buyer or buyers.

Retention and Transaction Bonuses

Accordingly, in order to provide an incentive for you to remain with ThermoRetec
through the  completion of the sale of three of the  ThermoRetec  Business Units
(as defined below), we will pay you both a retention bonus  ("Retention  Bonus")
and a transaction bonus ("Transaction Bonus").

The  Retention  Bonus  will  be  payable  to you  upon  the  sale  of the  three
ThermoRetec  Business  Units for which you have  direct or  indirect  management
responsibility  and shall be equal to 100% of your base  salary as of the end of
calendar 1999, that is, $150,000.

This  Retention  Bonus  will be paid to you in one lump sum on or before 30 days
following the sale of all of the ThermoRetec  Business Units listed in the table
below.  In addition to the  Retention  Bonus,  we agree to pay you an additional
Transaction  Bonus  in  recognition  of  your  efforts  to  maximize  the  price
ThermoRetec receives for selling the three Business Units listed below.

The  following  table  describes the  Transaction  Bonus you will be eligible to
receive if the combined  sales price for the  ThermoRetec  Business Units listed
below  is equal to or  greater  than the  combined  Threshold  Price  for  these
Business  Units.  Sales price shall be the stated  purchase price after required
adjustments  in the  respective  purchase  and  sale  agreements  (for  example,
adjustments to the closing balance sheet). The bonus amount will be based on the
combined threshold price and incentive amounts for the three businesses.



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Jeff Powell
January 31, 2000
Page 2


         Business               Incentive Amount           Threshold Price
ThermoRetec Nuclear Services       $28,000                  $17,000,000
ThermoRetec Soil Recycling         $25,000                  $15,000,000
ThermoRetec Fluids Recycling       $22,000                  $13,000,000
Combined Business Units            $75,000                  $45,000,000


Additionally,  if the sales price of the  combined  business  units  exceeds the
combined  Threshold Price listed above, you will be paid 1.0 % of the difference
between  the actual  sales price and this  Threshold  Price.  Example:  If these
ThermoRetec  Business Units were sold for  $50,000,000  your total incentive for
achieving  that  sales  price  would be  $125,000.  This  includes  $75,000  for
achieving the $45,000,000 combined sales price and an additional $50,000 for the
$5,000,000 over the $45,000,000  target price ($5,000,000 x .01 = $50,000).  The
Transaction Bonus will be paid to you on or before 30 days following the sale of
the three business units with which you are involved.

Terms of Agreement

1.   ThermoRetec agrees to continue to employ you on the same terms and with the
     same benefits as you currently  enjoy, as an  employee-at-will.  In return,
     you agree to remain in such employ and to continue to devote your full time
     and best efforts to  ThermoRetec as an  employee-at-will  until the closing
     date of the sale of the  ThermoRetec  Business  Units  with  which  you are
     involved.

2.   You  understand  that  ThermoRetec  retains  the  right to  terminate  your
     services  without "cause" (as defined  below),  and you retain the right to
     terminate  your  services  from  ThermoRetec  at any time.  If  ThermoRetec
     terminates you for its convenience and without cause, you will be paid your
     full and unreduced  Retention  Bonus in  accordance  with the terms of this
     letter,  even if no sale has taken place.  If you terminate your employment
     prior to the sale closing date, or ThermoRetec  terminates  your employment
     for  cause , you  will  forfeit  any and all  payments  that  you  would be
     entitled to under this agreement.

3.   For  the  purposes  of this  agreement,  "cause"  shall  be  determined  by
     ThermoRetec in the exercise of good faith and reasonable judgement and will
     include  any  breach  of this  agreement  by you or any act by you of gross
     personal  misconduct,  insubordination,  misappropriation  of funds, fraud,
     dishonesty, gross neglect of or failure to perform the duties


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Jeff Powell
January 31, 2000
Page 3


     reasonably  required  of  you  pursuant  to  this  agreement,  engaging  in
     activities that are competitive with ThermoRetec's  business or any conduct
     which  is  in  willful  violation  of  any  applicable  law  or  regulation
     pertaining to the business.

4.   For  purposes of this  agreement  we agree that your  ThermoRetec  Business
     Units will be considered sold when any person or entity (other than another
     Thermo Electron business unit) purchases substantially all of the assets or
     shares of those  Business  Units.  Accordingly,  neither a Retention  nor a
     Transaction  Bonus will be paid to you if you  participate as a prospective
     owner in a management  buy-out of these or any other  ThermoRetec  Business
     Units.  The  ThermoRetec  Business  Units  are:  ThermoRetec  Consulting  &
     Engineering,  ThermoRetec Nuclear Services, ThermoRetec Soil Recycling, and
     ThermoRetec Fluids Recycling.

5.   You  understand  that all payments made under this agreement are subject to
     appropriate federal, state, city or other tax withholding requirements.  In
     exchange for our covenants to you under this agreement,  you hereby release
     ThermoRetec and its parent,  subsidiaries and affiliates, and each of their
     respective agents,  employees,  directors,  and officers,  (hereafter,  the
     "Releasees") of and from any and all costs, liabilities,  losses, expenses,
     and  compensation,  (hereafter,  "Claims"),  which  you  had,  have  or may
     hereafter have or assert against the Releasees for any wrongful termination
     of employment, including termination based on age, sex, race, disability or
     other discrimination under the Civil Rights Act of 1964 as amended, the Age
     Discrimination in Employment Act of 1967, or other federal, state, or local
     laws prohibiting  such  discrimination,  or under federal,  state, or local
     employment laws,  provided,  however,  that this release shall not apply to
     any claims  other than for wrongful  termination  that you may have against
     ThermoRetec, including claims under this letter agreement.

6.   You  acknowledge  that this agreement  supersedes  any prior  agreements or
     understandings,  whether  oral or  written,  between  you  and  ThermoRetec
     pertaining  to  any  incentive  payments  being  offered  to  employees  of
     businesses being sold in connection with the reorganization,  and that this
     agreement constitutes the entire agreement between us.

The next few months are apt to be both stressful and  challenging for all of us.
I'm hopeful this agreement will provide you some personal security regarding the
inevitable changes ahead. I know that I will need your help and understanding in
the next few months, as well as your continued  assistance and support. You have
my personal pledge that I will do my best to help you and our people emerge from
this experience with pride, with our dignity intact, and with a bright


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Jeff Powell
January 31, 2000
Page 4


future. If you have any questions  regarding any of the terms of this agreement,
please do not hesitate to contact me.

Once you have read and understood the terms of this  agreement,  please indicate
your agreement by signing below on the line above your typewritten  name, make a
copy for your  records,  and return the  original  document  to me no later than
February 11, 2000.


                                   Sincerely yours,


                                   /s/ Robert W. Dunlap
                                   ---------------------------------------------
                                   Robert W. Dunlap, President & CEO
                                   ThermoRetec Corporation



Accepted and agreed:



/s/ Jeffrey L. Powell                     February 7, 2000
----------------------------------        --------------------------------------
NAME                                      Date



<PAGE>


                   Release of Claims and Signature of Acceptance

In exchange  for the Enhanced  Severance  Program  offered to me by  ThermoRetec
Corporation in this Agreement dated April 10, 2000 (the  "Agreement"),  I hereby
release  ThermoRetec   Corporation  and  Thermo  Electron   Corporation,   their
subsidiaries and affiliates  (collectively the  "Corporation") and its officers,
directors,  employees and legal  predecessors  from all claims,  liabilities and
causes of action,  whether known or unknown, which I have, may have, or claim to
have against the Corporation based upon or arising out of my employment with the
Corporation,  other than claims arising out of the Agreement. I hereby agree not
to file any lawsuit to assert such claims, which include, but are not limited to
any claims for breach of contract,  wrongful  termination,  or age,  sex,  race,
disability or other  discrimination  under the Civil Rights Act of 1964, the Age
Discrimination in Employment Act of 1967, or any other federal,  state, or local
laws prohibiting such  discrimination.  As used herein, the Corporation includes
any and all parents, divisions or subsidiaries of the Corporation.

I understand that I have been advised to seek the advice of an attorney, if I so
choose, prior to signing this release and that I am giving up any legal claims I
have against the Corporation by signing this release.  I further understand that
I may have 21 days to consider this agreement,  that I may revoke it at any time
during the 7 days after I sign it, and that it shall not become  effective until
that 7-day revocation  period has passed. I fully understand my right to take 21
days to consider  signing  this release and,  after  having  sufficient  time to
consider my options,  I hereby waive my right to take the full 21 day period.  I
acknowledge that I am signing this release knowingly,  willingly and voluntarily
in exchange for the additional severance payment described in the Agreement.

I acknowledge  that I have carefully read and fully  understand  this Release of
All Claims and I have not relied on any statement, written or oral, which is not
set out in this document.


/s/ Robert W. Dunlap                       /s/ Jeffrey L. Powell
-------------------------------------      -------------------------------------
Robert W. Dunlap                           Jeffrey L. Powell


                                           April 12, 2000
                                           -------------------------------------
                                           Date



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                                                       ThermoRetec Corporation
                                                  9 Damonmill Square, Suite 3A
                                                        Concord. MA 01742-2851

April 10, 2000

Jeffrey L. Powell
1 Walnut Street
Acton, MA 01720



Dear Jeff:

This letter confirms our discussion and outlines the Enhanced  Severance Program
which shall be offered to you in the event that your  employment  is  terminated
without  "Cause"  (as defined  below) or as a result of "Change in Control"  (as
defined below) of ThermoRetec  Corporation  ("Retec").  The  availability of the
Enhanced Severance Program, upon an employee's  separation,  is conditioned upon
and will  require  the  execution  of a release  of claims (a sample of which is
attached to this letter).  If you do not execute the release of claims, you will
only be eligible to receive the Retention Bonus and Transaction Bonus previously
negotiated.

If you accept employment comparable to your present position with another entity
that is a subsidiary or affiliate of Thermo Electron  Corporation,  you will not
be eligible for the Enhanced Severance  Program.  Also, if you participate as an
equity owner in a management  buyout of Retec or any Retec  subsidiary  you will
not be eligible for the Enhanced Severance Program.

In order to maintain  eligibility for any of the below outlined benefits,  Retec
requires  that you  remain a  regular  active  employee  of  Retec  unless  your
employment is terminated  without Cause or as a result of a Change in Control of
ThermoRetec Corporation.

For  purposes of the  Agreement,  "Cause"  shall be  determined  by Retec in the
exercise of good faith and reasonable judgement. "Cause" will include but not be
limited to breach of this  Agreement  by you,  any act by you of gross  personal
misconduct,  gross insubordination,  material  misappropriation of funds, fraud,
dishonesty,  gross  neglect  of or failure  to  perform  the  duties  reasonably
required of you pursuant to your  employment,  engaging in  activities  that are
competitive with Retec's  business or any conduct which is in willful  violation
of any applicable law or regulation pertaining to Retec's business.

"Change  in  Control"  shall  mean  the  merger,  consolidation,  reorganization
liquidation,  dissolution,  or similar transaction entered into by Retec (except
with  Thermo  Electron  Corporation  or  an  affiliate  thereof),  the  sale  or
disposition of 50% or more of the existing assets of RETEC in one or a series of
transactions,  or the  change  in  ownership  of 50% or more  of the  beneficial
ownership of the outstanding shares of common stock of RETEC.

If (i) you are terminated without cause or (ii) if as a result of such Change in
Control  you are  terminated  and not offered a position by Retec or a successor
entity with  comparable  salary,  compensation,  bonus and benefits,  or if your
principal work location is moved by more than 50 miles, you will be eligible for
the Enhanced Severance Program.  However,  if as a result of a Change in Control
you are offered by Retec or a successor entity a position with comparable



<PAGE>




Jeffrey L. Powell                                                   ThermoRetec
April 10, 2000


salary, compensation, bonus and benefits and your principal work location is not
moved by more than 50 miles, you will not be eligible for the Enhanced Severance
Program.

Salary Continuation

Beginning the day following your termination date, you shall be placed on salary
continuation through the regular payroll system, at your regular biweekly salary
for a period of 52 weeks.

Vacation

Accrued but unused  vacation  will be paid to you with the first check  covering
the salary continuation period.  Vacation payments will be calculated using your
regular  biweekly base  compensation.  You will not accrue  additional  vacation
credit beyond your termination date.

Medical, Dental, and Life Insurance

Through  the  end of your  salary  continuation  period,  you  may  continue  to
participate in any medical,  dental and/or life insurance  programs in which you
are currently  enrolled,  provided that you pay the regular  employee portion of
these benefits where  applicable.  Once medical and dental coverage ceases,  you
will be notified of your  eligibility  to continue  medical and dental  coverage
under the provisions of COBRA.

STD and LTD

Both short-term and long-term disability coverage will cease as of your last day
of active employment.

Employee Assistance Program

This program will  continue to be available to you and your  dependents  through
the end of your salary continuation period.

Employee Stock Purchase Plan

You will continue to be eligible for  participation  under the normal plan rules
through the end of your salary continuation period.

401K Plan


You will continue to be eligible for  participation  under the normal plan rules
through the end of your salary continuation period.




<PAGE>



Jeffrey L. Powell                                                   ThermoRetec
April 10, 2000

Outplacement Program

The company will arrange,  at no cost to you,  outplacement  counseling services
through  Keystone  Associates.  Keystone will  coordinate  the delivery of these
services at their offices in Burlington, Massachusetts. You shall be eligible to
begin receiving these services immediately upon termination, or you may schedule
the  start  of this  program  anytime  within  90 days  after  the  date of your
termination. The major elements of this comprehensive program include:

-     Counseling
      -     Resume development
      -     Research skills
      -     Self assessment and job targeting
      -     Effective correspondences
      -     Networking and other search techniques
      -     Interview training

-     Administrative Support
      -     Office space and private telephone line with voice mail
      -     Research assistance
      -     Reference library

The outplacement services described above will be available for a period of four
months, renewable (should you need additional services) for an additional period
of four months.

I am hopeful these benefits, should you qualify for them, will be helpful to you
in establishing  new career  directions after your long and fruitful career with
Retec and Thermo  Electron.  Thank you for all your  efforts  over many years of
employment with our corporation.

Sincerely yours,


/s/ Robert W. Dunlap
----------------------------------------
Robert W. Dunlap
President
ThermoRetec Corporation