EXHIBIT 10 (qq)


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                                   ----------

                             THE TIREX CORPORATION

                                   ----------

                     RUBBER CRUMB PURCHASE OPTION AGREEMENT

      Rubber Crumb Purchase Option Agreement, made this 19th day of August 1998,
between:

                      ENERCON America Distribution Limited
                      540 Tansy Lane
                      Westerville, Ohio 43081

                                             (the "Operator")

                                             and

                      The Tirex Corporation
                      740 St. Maurice, Suite 201
                      Montreal, Quebec
                      Canada H3C 1L5

                                             (the "Manufacturer")

      Whereas,  the  Manufacturer  and  the  Operator  are  parties  to  certain
equipment lease and purchase  agreements,  of even date herewith (the "Equipment
Lease and  Purchase  Agreements"),  between the  Manufacturer  and the  Operator
respecting the sale by the  Manufacturer and the Purchase by the Operator of the
"Purchased  Equipment" and the operating  lease,  between the  Manufacturer,  as
lessor, and the Operator, as lessee, respecting the "Leased Equipment", as those
terms are defined in the said Equipment Lease and Purchase Agreements.

      Whereas,  in  consideration  for the premises and the mutual promises made
therein,  the Operator has agreed,  pursuant to the Equipment Lease and Purchase
Agreements,  to enter into this Option Agreement with the Manufacturer  pursuant
to which the Operator hereby grants to the  Manufacturer  the option to purchase
up to forty percent (40%) of the rubber crumb yielded by the  disintegration  of
scrap tires in the TCS-1 System and the TCTS-1  System which are the  respective
subjects of the said  Equipment  Lease and  Purchase  Agreements  (the  "Subject
System").

      Now, Therefore, it is agreed as follows:

1.    Definitions

      1.1 "Manufacturer" shall mean The Tirex Corporation and its successors and
assigns.


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      1.2 "Operator"  shall mean ENERCON  America  Distribution  Limited and all
other  corporations,  partnerships,  or  other  entities,  now or in the  future
controlled  by, under common  control  with, or in control of,  ENERCON  America
Distribution Limited, jointly and severally.

      1.3 All other  Capitalized  terms used  herein and not  otherwise  defined
shall have the respective meanings attributed thereto in the Equipment Lease and
Purchase Agreements.

2.    Grant of Option

      The Operator hereby grants to the Manufacturer an option (the "Option") to
purchase  up to  forty  percent  (40%)  of  the  rubber  crumb  yielded  by  the
disintegration  of  scrap  tires  in the  Subject  Systems  (the  "Rubber  Crumb
Output").

3.    Term of Option

      The term of the Option shall be coextensive with the term of the operating
lease provided for in Section 4 of the respective  Equipment  Lease and Purchase
Agreements and shall commence as of the Acceptance Date.

4.    Conditions of Option

      The Manufacturer's  rights to purchase the Rubber Crumb Output pursuant to
this Option shall be subject to fulfillment of the following condition:

      (a)   the Manufacturer shall furnish to the Operator,  in writing,  within
            ninety days of the Acceptance Date and every six months  thereafter,
            the Manufacturer's  anticipated purchase projections (the "Six-Month
            Projected  Purchase  Order")  specifying  the  grades,   types,  and
            quantities of Rubber Crumb Output which the Manufacturer  commits to
            purchase  within the  six-month  period  following  the date of such
            Projected Purchase Order;

      The price, terms, and conditions specified in the Projected Purchase Order
will be negotiated every six months for a period of six months.

5.    Inspection of Books

      Upon written request, the Manufacturer or its designated agent may examine
the books and records of the Operator only insofar as they relate to this Rubber
Crumb Purchase Option Agreement and are reasonably required to verify the volume
of  rubber  crumb  produced  by the  operation  of  the  Subject  Systems.  Such
examination  shall take place at the offices of the Operator  only during normal
business office operating hours.

6.    Assignment


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      6.1 This Option  Agreement  may not be assigned by the Operator  except as
part of the assignment of the Equipment Lease and Purchase Agreement,  which may
only be assigned  pursuant to the express written  consent of the  Manufacturer,
and any such  assignment  shall not  relieve  the  Operator  of its  obligations
hereunder unless expressly waived in writing by the Manufacturer.

      6.2 This  Option  Agreement  may be  transferred,  assigned,  pledged,  or
hypothecated  by the  Manufacture  as  part  of the  sale  of  its  business  or
otherwise.

7.    Notices

      All notices required or permitted to be given hereunder shall be mailed by
certified mail, or delivered by hand or by recognized  overnight  courier to the
party to whom such notice is required or permitted to be given  hereunder at the
address  set forth  above for such  party,  in all cases with  written  proof of
receipt  required.  Any such  notice  shall be deemed to have  been  given  when
received by the party to whom notice is given, as evidenced by written and dated
receipt of the  receiving  party.  Either  party may change the address to which
notice to it is to be  addressed,  by  written  notice to the  other  party,  as
provided herein.

8.    Binding Effect.

      8.1 This  Option  Agreement  shall  bind and inure to the  benefit  of the
parties  hereto  and their  respective  legal  representatives,  successors  and
assigns, provided, however, that this Option Agreement cannot be assigned by the
Operator except in accordance with Section 6.1 hereof.  Nothing herein expressed
or implied  is  intended  or shall be  construed  to confer  upon or to give any
person,  firm or corporation  other than the parties hereto and their respective
legal representatives, successors and assigns any rights or benefits under or by
reason of this Option Agreement.

      8.2 All the right,  title,  and  interest of the  Manufacturer  under this
Option  Agreement  may be  enforced by the  Manufacturer,  its  successors,  and
assigns.  This  Option  Agreement  shall  continue  in  full  force  and  effect
notwithstanding  the death,  incapacity,  or  dissolution of the Operator or the
increase,  decrease,  or change in the  personnel of or members of the Operator,
and  shall be  binding  upon  the  Operator  and the  Operator's  estate,  legal
representatives, heirs, and successors.

9.    Further Assurances

      At any time, and from time to time, after the execution of this Agreement,
each party will execute such additional  instruments and take such action as may
be  reasonably  requested by the other party to confirm or perfect  title to any
property transferred hereunder or otherwise to carry out the intent and purposes
of this Agreement.

10.   Waiver


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      Any  failure  on the part of any party  hereto  to comply  with any of its
obligations,  agreements or conditions hereunder may be waived in writing by the
party to whom such compliance is owed.

11.   Brokers

      Neither  party has  employed  any  brokers or finders  with regard to this
Agreement, unless otherwise described in writing to all parties hereto.

12.   Headings

      The section and  subsection  headings in this  Agreement  are inserted for
convenience  only and shall not affect in any way the meaning or  interpretation
of this Agreement.

13.   Governing Law

      This Agreement shall be governed by the laws of the State of Delaware.

14    Entire Agreement

      This Agreement and the premises and mutual promises in the Equipment Lease
and Purchase  Agreement  constitute the entire agreement of the parties covering
everything  agreed upon or understood  with respect to the Option.  There are no
oral promises, conditions, representations,  understandings,  interpretations or
terms of any kind as conditions or inducements to the execution hereof.

15.   Severability

      If any part of this Agreement is deemed to be unenforceable the balance of
this Agreement shall remain in full force and effect.

16.   Publicity

      All  notices  to third  parties  and all other  publicity  concerning  the
transactions  contemplated  by this  Agreement  shall be  subject  to the  prior
approval of counsel to the Manufacturer.

17.   Counterparts

      This Agreement may be executed in any number of  counterparts  and by each
party on a separate  counterpart,  each of which when so executed and  delivered
shall be an original, but all of which together shall constitute one Agreement.


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         In  Witness  Whereof,  the  parties  hereto  have  caused  this  Option
Agreement to be executed the day and year first above written.

whatsoever.

                                       ENERCON AMERICA DISTRIBUTION LIMITED

                                       By /s/ David L. Holmes
                                          --------------------------------------
                                              David L. Holmes

                                       THE TIREX CORPORATION

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


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