EXHIBIT 10 (zz)


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                                   ----------

                              THE TIREX CORPORATION

                                   ----------

                                MANAGING DIRECTOR

                                       OF

                           EUROPEAN MARKET DEVELOPMENT

                                   ----------

                        CONTRACTUAL EMPLOYMENT AGREEMENT

      Contractual  Employment Agreement,  executed this 1st day of July, 1997 to
be effective retroactively as of January 15, 1997 between The Tirex Corporation,
a Delaware corporation ("Tirex") with offices located at 740 St. Maurice,  Suite
201 Montreal,  Quebec,  Canada H3C 1L5 and Alan Crossley,  Gran Via de Hortaleza
82A, 1*B, 28043 Madrid, Spain ("Crossley").  For purposes of this Agreement, the
term "Tirex" shall mean The Tirex Corporation and 3143619 Canada Inc. (known and
doing   business  as  "Tirex  Canada   Inc."),   and  all  other   corporations,
partnerships,  or other  entities,  now or in the future  controlled  by,  under
common  control  with,  or in control  of, The Tirex  Corporation,  jointly  and
severally.

      Whereas,  Tirex  is in the  business  of  developing,  manufacturing,  and
distributing  cryogenic scrap tire  disintegration  equipment and processes (the
"TCS-1  System")  for the  recovery of rubber  crumb,  wire and fiber from scrap
tires and wishes to launch the sale of its  products and services in the markets
of the European Union.

      Whereas,  Crossley has  expertise and  substantial  business and marketing
experience and contacts in the European market as well as in various other areas
in Asia and the Middle East, which can be important to Tirex.

      Whereas,  Tirex  wishes to  assure  itself of the  marketing  services  of
Crossley for the period provided in this  Agreement,  and Crossley is willing to
provide  such  services  to Tirex  for the  said  period  under  the  terms  and
conditions hereinafter provided.

      Now, Therefore,  Witnesseth, that for and in consideration of the premises
and of the mutual promises and covenants  herein  contained,  the parties hereto
agree as follows:


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1.    Term and Employment

      1.1 Tirex agrees to and does hereby engage  Crossley,  and Crossley agrees
to and does hereby accept  engagement by Tirex as Managing  Director of European
Market Development for the one-year period,  which commenced on January 15, 1997
(the "Engagement Period").

      1.2 The terms of this Agreement  shall be  automatically  extended for two
successive  one-year periods,  ("Extension  Periods") unless,  not later than 30
days prior to the end of the  Engagement  Period or the then  current  Extension
Period, either party shall give written notice to the other that such party does
not wish the term of this Agreement to be extended beyond the current Engagement
or Extension Period on the terms then in effect.

      1.3 This Agreement  cancels and replaces the European  Market  Development
Consulting Agreement (the "Consulting  Agreement"),  entered into by the parties
hereto  on  May  29,  1997,   retroactively   effective  to  January  15,  1997.
Notwithstanding  the foregoing,  the said  Consulting  Agreement shall remain in
effect with respect to all matters  pertaining to certain market studies for the
Iberian Peninsular and India, which were heretofore  conducted by GAPCO, Inc., a
corporation under the control of Crossley, and the compensation paid therefor by
Tirex, receipt of which is hereby acknowledged by Crossley.

2.    Duties

      2.1 Crossley shall be responsible for undertaking and effecting activities
necessary  to  establish  and develop  markets for the TCS-1  System and for the
crumb  rubber  which  will be  produced  by the  operation  of the TCS-1  System
throughout  the European  Economic  Union,  India,  Pakistan,  Saudi Arabia (the
"Territory"),  and such  other  areas as the  parties  may,  from  time to time,
mutually  agree.  Such  activities  shall  include,  but not be limited  to, the
following:

      (a)   setting up the appropriate  corporate structure and organization for
            importing  and  distributing  the TCS-1 System and crumb rubber into
            and throughout the Territory;

      (b)   establishing and managing a network of TCS-1 System distributors and
            crumb rubber brokers in the Territory;

      (c)   arranging   importation  and   installation  of  TCS-1  Systems  and
            providing   customer   support  as  required  to  ensure   effective
            installation and maintenance of all TCS-1 Systems in the Territory;

      (d)   providing after-sales support to customers;

      (e)   serving  as a liaison  with  Tirex in North  America  on  matters of
            interest  to  Tirex,   including   but  not  limited  to   technical
            developments in the use of crumb rubber;


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      (f)   representing  Tirex's  interests in any other activities which Tirex
            may, from time to time, undertake in the Territory,  including local
            manufacturing and trading in crumb rubber.

      2.2 Tirex will, at all times during the Engagement Period:

      (a)   provide  Crossley  with  appropriate   support,   including  product
            specifications,  sales  literature,  and  all  other  necessary  and
            available sales materials; and

      (b)   ensure that all members of Tirex's  technical staff in the Territory
            are fully trained and able to provide effective after sales services
            to customers.

      All such services are to be performed only upon direct  authorization from
Tirex and must be performed by Crossley directly.

3.    Compensation

      3.1 For all  services to be  rendered  hereunder  by  Crossley  during the
Engagement Period, Crossley shall receive the following compensation:

      (a)   a salary,  payable monthly, at the annual rate of $75,000 (Canadian)
            commencing as of July 1, 1997.

      (b)   a sales  commission of eight  percent (8%) of the purchase  price of
            all sales of TCS-1  Systems  within  the  Territory  which  shall be
            payable,  on a pro-rata basis,  within two weeks of receipt by Tirex
            of payments therefor, provided however that Tirex shall deduct, from
            the amount of any sales  commissions due under this  Paragraph,  all
            salary  payments  made  or  payable  to  Crossley  pursuant  to  sub
            paragraph 3.1(a), above.

      3.2 In the event that this  Agreement is  terminated by Tirex prior to the
end of the Engagement Period or any Extension Period, pursuant to Tirex's notice
that it does not wish to extend this  Agreement,  as provided in  Paragraph  1.2
above, and Crossley gives written notice to Tirex, within 30 days of his receipt
of such notice,  that he objects to the termination of this Agreement,  then the
8% sales commission provided under subparagraph 3.1(b),  above, shall be payable
to Crossley on all sales of the TCS-1  System in the  Territory  for a period of
two years following such termination.

      3.3 In the  event  that,  from  time to  time,  Tirex  shall  not have the
financial  resources  to pay the salary  provided for above,  then,  the Tirex's
obligation  to pay such salary will be  satisfied by the issuance to Crossley of
shares of the common stock of the Company ("Compensation  Shares"), which shares
shall  constitute  compensation  pursuant  to the terms of this  Agreement.  All
Compensation Shares will be issued to Crossley at a value equal to fifty percent


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(50%) of the  average of the high and low bid prices of Tirex  America's  common
stock  as  traded  in the  over-the-counter  market  and  quoted  in the  NASDAQ
Electronic  Bulletin Board during the period when such Compensation  Shares were
earned.

4.    Reimbursement of Expenses

      During the Engagement Period,  Tirex shall reimburse Crossley for properly
documented  expenses paid by him on behalf, or for the account,  of Tirex in the
course of carrying out his duties hereunder.  Such  reimbursements  shall not be
made for any expenses  other than those  listed below and the amount  reimbursed
for any permitted category of expense shall not exceed the following:

Office rent                                                     $20,000
Office and marketing assistant                                   25,000
Advertising and publicity                                        20,000
Multi-lingual translation of product
  information (excluding both English & French)                  15,000
Legal costs                                                      10,000
Travel to potential clients                                      15,000
Attendance at trade shows                                        10,000

5.    Termination

      This  Agreement  may be  terminated  at any  time  prior to the end of the
Engagement  Period or any Extension  Period,  by mutual written Agreement of the
parties and pursuant to the following:

      5.1 For Cause. The Company may terminate the Employee's  employment at any
time "for cause" with  immediate  effect upon  delivering  written notice to the
Employee.  For  purposes of this  Agreement,  "for  cause"  shall  include:  (a)
embezzlement,  theft, larceny, material fraud, or other acts of dishonesty;  (b)
material  violation by employee of any of his obligations  under this Agreement;
(c) conviction of or entrance of a plea of guilty or nolo contendere to a felony
or other crime which has or may have a material adverse effect on the Employee's
ability to carry out his duties under this  Agreement or upon the  reputation of
the Company; (d) conduct involving moral turpitude; (e) gross insubordination or
repeated  insubordination after written warning by the President of the Company;
or (f)  material  and  continuing  failure by the Employee to perform the duties
described in Section 2 above in a quality and  professional  manner for at least
thirty  (30)  days  after  written  warning  by the  Board of  Directors  or the
President of the Company.  Upon  termination  for cause,  the Company's sole and
exclusive obligation will be to pay the Employee his compensation earned through
the  date  of  termination,  and  the  Employee  shall  not be  entitled  to any
compensation after the date of termination.

      5.2 Upon Death.  In the event of the  Employee's  death during the term of
the this Agreement,  the Company's sole and exclusive  obligation will be to pay
to the Employee's


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spouse,  if living,  or to his  estate,  if his spouse is not then  living,  the
Employee's compensation earned through the date of death.

      5.3 Upon Disability.  The Company may terminate the Employee's  employment
upon the Employee's total disability. The Employee shall be deemed to be totally
disabled if he is unable to perform his duties under this Agreement by reason of
mental or physical illness or accident for a period of three consecutive months.
Upon termination by reason of the Employee's disability,  the Company's sole and
exclusive obligation will be to pay the Employee his compensation earned through
the date of termination.

6.    Secrets

      Crossley  agrees that any trade secrets or any other like  information  of
value  relating to the business  and/or field of interest of Tirex or any of its
affiliates, or of any corporation or other legal entity in which Tirex or any of
its  affiliates  has an  ownership  interest of more than  twenty-five  per cent
(25%),  including  but not  limited  to,  information  relating  to  inventions,
disclosures,    processes,   systems,   methods,   formulae,   patents,   patent
applications,  machinery,  materials,  research  activities and plans,  costs of
production,  contract forms, prices, volume of sales,  promotional methods, list
of names or classes of customers,  which he has heretofore  acquired  during his
engagement by Tirex or any of its  affiliates or which he may hereafter  acquire
during  the  Engagement   Period  and  the  three-year  period  beginning  after
termination of the Engagement Period as the result of any disclosures to him, or
in any other way,  shall be regarded as held by Crossley and his  personnel,  if
any, in a fiduciary  capacity solely for the benefit of Tirex, its successors or
assigns,  and shall not at any time, either during the term of this Agreement or
thereafter,  be disclosed,  divulged,  furnished, or made accessible by Crossley
and his personnel,  if any, to anyone,  or be otherwise used by them,  except in
the regular course of business of Tirex or its affiliates. Information shall for
the purposes of this  Agreement be  considered  to be secret if not known by the
trade generally,  even though such information may have been disclosed to one or
more third parties pursuant to distribution agreements, joint venture agreements
and other agreements entered into by Tirex or any of its affiliates.

7.    Non-Competition

      Unless  this  Agreement  is  terminated  by Tirex  prior to the end of the
Engagement Period or any Extension Period, without cause and over the objections
of Crossley,  during the two years  following the termination of this Agreement,
Crossley will not provide  consulting  services  either as a consultant or as an
employee, either directly or otherwise to any business which is, or is preparing
or intending to be, in competition with Tirex.

8.    Assignment


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      8.1  This  Agreement  may be  assigned  by  Tirex  as part of the  sale of
substantially all of its business;  provided,  however, that the purchaser shall
expressly  assume all obligations of Tirex under this Agreement.  Further,  this
Agreement  may be  assigned  by Tirex to an  affiliate,  provided  that any such
affiliate shall expressly  assume all obligations of Tirex under this Agreement,
and provided  further that Tirex shall then fully  guarantee the  performance of
the Agreement by such  affiliate.  Crossley  agrees that if this Agreement is so
assigned,  all the terms and conditions of this  Agreement  shall obtain between
such  assignee and himself  with the same force and effect as if said  Agreement
had been made with such assignee in the first instance.

      8.2 This Agreement is personal to Crossley and may not be assigned by him.

9.    Entire Understanding

      This Agreement contains the entire  understanding  between the parties and
supersedes all prior and collateral  communications,  reports,  agreements,  and
understandings  between the parties.  No change,  modification,  alteration,  or
addition to any provision  hereof shall be binding  unless in writing and signed
by authorized  representatives  of both parties.  This Agreement  shall apply in
lieu  of  and  notwithstanding  any  specific  statement   associated  with  any
particular information or data exchanged, and the duties of the parties shall be
determined   exclusively   by   the   aforementioned   terms   and   conditions.
Notwithstanding the foregoing, the parties agree that certain provisions of this
Agreement  may be changed  or  amended  for the  purpose  of  accommodating  tax
considerations  of the parties without  affecting the basic terms and conditions
of this Agreement.

10.   Survival of Certain Agreements

      The covenants and agreements set forth in Articles 4 and 5, hereof,  shall
survive the expiration of the Engagement Period and shall survive termination of
this Agreement and remain in full force and effect.

11.   Notices

      11.1 All notices  required or  permitted  to be given  hereunder  shall be
delivered by hand, certified mail, or recognized overnight courier, in all cases
with written  proof of receipt  required,  addressed to the parties as set forth
below and shall be deemed  given upon  receipt as evidenced by written and dated
receipt of the receiving party.

      11.2 Any notice to Tirex or to any assignee of Tirex shall be addressed as
follows:

                          The Tirex Corporation
                          740 St. Maurice, Suite 201
                          Montreal, Quebec


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                          Canada H3C 1L5

      11.3 Any notice to Crossley shall be addressed as follows:

                          Mr. Alan Crossley
                          Gran Via de Hortaleza 82A, 1oB
                          28043 Madrid, Spain

      11.4 Either  party may change the  address to which  notice to it is to be
addressed, by notice as provided herein.

12.   Applicable Law

      This Agreement  shall be interpreted  and enforced in accordance  with the
laws of the State of Delaware.

13.   Interpretation

      Whenever possible,  each Article of this Agreement shall be interpreted in
such  manner as to be  effective  and valid  under  applicable  law,  but if any
Article is  unenforceable  or  invalid  under such law,  such  Article  shall be
ineffective only to the extent of such  unenforceability or invalidity,  and the
remainder of such Article and the balance of this Agreement  shall in such event
continue to be binding and in full force and effect.

14.   Prior Agreements

      Subject to the provisions of Paragraph 1.3, this Agreement  supersedes and
cancels  any and all prior  agreements,  whether  written or oral,  between  the
parties.

15.   Arbitration

      In the event of any dispute among the parties  hereto with respect to this
Agreement,  the matters at issue will be submitted to the International  Chamber
of Commerce in Geneva for  arbitration,  and the  findings of the latter will be
binding on both parties.

      In Witness  Whereof,  the parties hereto have executed the above Agreement
as of the day and year first above written.


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                                           The Tirex Corporation

                                           By /s/ Terence C. Byrne
                                              ----------------------------------
                                                  Terence C. Byrne, President

                                              /s/ Alan Crossley
                                              ----------------------------------
                                                  Alan Crossley


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