Exhibit 10.17

                            STOCK PURCHASE AGREEMENT

     This  Agreement  is made and  entered  into on this 30th day of  September,
1996,  by  and  between  American   Physicians  Service  Group,  Inc.,  a  Texas
corporation (the "Buyer"),  and Exsorbet Industries,  Inc., an Idaho corporation
(the "Seller").

     In  consideration  of the premises and the mutual promises herein made, and
in  consideration  of the  representations,  warranties,  and  covenants  herein
contained, the Parties agree as follows:

1. Definition~

     "Exsorbet"  and "Exsorbet  Industries.  Inc." refer to that certain  entity
which is  incorporated  under  the laws of the  State  of Idaho  under  the name
"Exsorbet Industries, Inc." as well as any successor corporation.

     "Shareholder Rights Agreement" means an Agreement by and between American 
Physicians Service Group, Inc. and Exsorbet Industries, Inc. dated September 30,
1996 and entitled "Shareholder Rights-Agreement..

     "Stock Put Agreement" means an Agreement by and between American Physicians
Service Group, Inc. and Exsorbet Industries, Inc. dated September 30, 1996, and
entitled "Stock Put Agreement."

2. Purchase and Sale of 1,200,000 Shares of Common Stock.

     (a) Basic  Transaction.  On and subject to the terms and conditions of this
Agreement,  and  further subject  to the terms of the Stock  Put  Agreement  and
Shareholder  Rights Agreement,  Buyer agrees to, and does hereby,  purchase from
Seller One Million Two Hundred Thousand  (1,200,000)  shares of common (capital)
stock of Exsorbet Industries,  Inc. at the price of Two Dollars and Seventy-Five
Cents (S2.75) per share.

     (b) Delivery of Share Certificate. Buyer acknowledges receipt of a 
certificate evidencing 1,200,000 shares of common stock of Exsorbet Industries,
Inc., such certificate being issued in the name of "American Physicians Service 
Group, Inc."

     (c) Payment.  Seller  acknowledges  receipt of Three  Million Three Hundred
Thousand U.S. Dollars  ($3,300,000) from Buyer as payment in full for the shares
of stock  specified  above.  Such sum is being  delivered by wire  transfer to a
banking account directed by Seller.

     3. Stock Registration. Unless and until registered, all of the shares of 
stock issued by Exsorbet Industries, Inc. pursuant to this Agreement may not be 
sold or transferred unless and until registered or pursuant to a valid exemption
from registration. All stock certificates issued pursuant to this Agreement 
shall bear a restrictive legend in substantially the following form:
<PAGE>

"No  sale,  offer  to  sell,  or  transfer  of the  shares  represented  by this
certificate  shall be made  unless a  registration  statement  under the Federal
Securities  Act of 1933,  as  amended,  with  respect to such  shares is then in
effect or an exemption from the registration requirements of said act is then in
fact applicable to said shares."

     4. Representations of Exsorbet. Seller represents and warrants the 
following facts to be true as of the time of execution of this Agreement:

(a) Exsorbet Industries, Inc. is a corporation duly organized and existing under
the laws of the State of Idaho, and is in good standing within the State of 
Idaho;

(b) Seller has full corporate power and authority to perform its obligations 
hereunder;

(c)  Neither  the  execution  and  the  delivery  of  this  Agreement,  nor  the
consummation of the transaction  contemplated hereby, will violate any corporate
bylaws, corporate charter, court orders, injunctions, decrees, or rulings;

(d) There is only one class of stock of  Exsorbet  Industries,  Inc.,  being the
common or capital stock of such corporation. There is only series of such stock.
There are no series or  classes  of stock  with any  preferred  or  preferential
rights;

(e) The stock of Exsorbet Industries, Inc. trades on the Nasdaq Stock Market, 
Inc. SmallCap Market under the symbol "EXSO;" and

(f) The shareholders of Exsorbet Industries, Inc. have been requested to approve
a proposed merger of such corporation into Consolidated Eco-Systems, Inc., a 
Delaware corporation. If such merger is approved, the Delaware corporation would
be the surviving corporation. Consolidated Eco-Systems,
Inc. is, or when organized will be, a wholly-owned subsidiary of Exsorbet 
Industries, Inc. In the event that the proposed merger is approved, Exsorbet 
Industries, Inc. binds and obligates itselfto insure, and warrants, that 
Consolidated Eco-Systems, Inc. would be bound by each and every term of this
Agreement.

     5. Representations and Understandings of American Physicians Service Group,
Inc.  Buyer  understands  that the  shares  of  stock  issued  pursuant  to this
Agreement  have  not  been,  and will not by the  terms  of this  Agreement  be,
registered under the Securities Act, or under any state securities laws, and are
being  offered  and sold in  reliance  upon federal  and  state  exemptions  for
transactions not involving any public offering.  The terms of this paragraph may
be modified or amended by other Agreements existing between the parties.

Buyer represents that:


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<PAGE>

(i) it is acquiring the shares of common stock of Exsorbet Industries, Inc.
solely for its own account for investment purposes, and not with a view to the 
distribution thereof;

(ii) it is a sophisticated investor with knowledge and experience in business 
and financial matters;

(iii) it has received certain  information  concerning the Buyer and has had the
opportunity to obtain additional information as desired in order to evaluate the
merits and the risks  inherent  in  holding  the stock of the  Seller,  provided
however that the terms  hereof shall be subject to a 60 day Stock Put  Agreement
during  which  time  Buyer  shall be  afforded  the  right to  conduct  full due
diligence inquiry of Seller, to the extent desired;

(iv) it is able to bear the economic risk and lack of liquidity inherent in 
holding the stock of Seller;

(v) it is an Accredited Investor, as defined by Regulation D promulgated 
pursuant to the Securities Act of 1933, as amended; and

(vi) it has full corporate  power and authority to enter into this Agreement and
to consummate the transaction contemplated hereunder.

     6. Subsidiary Disclosure. Exsorbet Industries, Inc. has provided 
information concerning its operating structure and specifically including a list
of its subsidiary corporations. Exsorbet represents and warrants that such 
information is complete and accurate. A list of subsidiary corporations
is attached hereto, marked as Exhibit "A" and incorporated herein by reference.

     7. No Third Party beneficiaries. This Agreement shall not confer any rights
or remedies upon any person or entity other than the parties hereto and their 
respective successors and permitted assigns.

     8. Succession and Assigment. This Agreement shall be binding upon and inure
to the benefit of the parties named herein and their  respective  successors and
permitted  assigns.  No party may assign either this  Agreement or any of his or
its rights,  interests,  or  obligations  hereunder  without  the prior  written
approval of the Buyer and the Sellers; provided.  however, that Buyer may assign
this Agreement and its rights hereunder to any subsidiary or affiliate of Buyer,
and Buyer may transfer or convey its rights in any shares of stock of the Seller
and the  Seller  may  merge  with that  certain  Delaware  corporation  known as
Consolidated  Eco-Systems,  Inc.,  provided that such  corporation  agrees to be
completely bound by all terms of all contracts in existence between the parties.

    9. Counterparts. This Agreement may be executed in one or more counterparts,
 each of


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<PAGE>

which shall be deemed an original but all of which together will  constitute one
and the same instrument.

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

     11.  Notices.   All  notices,   requests,   demands,   claims,   and  other
communications hereunder will be in writing. Any notice, request, demand, claim,
or other  communication  hereunder shall be deemed duly given if (and then three
business days after) it is sent by registered or certified  mail,  retum receipt
requested, postage prepaid, and addressed to the intended recipient as set forth
below:

 If to the Seller:   Copy to: Charles E. Chunn, Ir., 1401 South Waldron Road,
                                   Suite 201, Fort Smith, AR 72903.

 If to the Buyer:    Copy to: Duane K. Boyd, Jr., 1301 Capital of Texas Highway,
                                   Suite C300, Austin, TX  78746-6550.         
                  
 

Any Party may send any notice,  request,  demand,  claim, or other communication
hereunder  to the  intended  recipient  at the address set forth above using any
other means (including personal delivery,  expedited courier, messenger service,
telecopy,  telex,  ordinary  mail,  or  electronic  mail),  but no such  notice,
request,  demand, claim, or otha communication shall be deemed to have been duly
given  unless and until it actually is received by the intended  recipient.  Any
Party may change the address to which notices,  requests,  demands,  claims, and
other  communications  hereunder are to be delivered by giving the other Parties
notice in the manner herein set forth.

     12.  Governing Law. This Agreement shall be  governed  by and  construed in
accordance with the domestic laws of the State of Texas without giving effect to
any choice or conflict of law provision or rule that would cause the application
of the laws of any jurisdiction other than the State of Texas.

     13. Amendments and Waivers.  No amendment of any provision ofthis Agreement
shall be valid  unless the same shall be in writing  and signed by the Buyer and
the Seller. No waiver by any Party of any default, misrepresentation,  or breach
of warranty or covenant  hereunder,  whether intentional or not, shall be deemed
to extend to any prior or subsequent  default,  misrepresentation,  or breach of
warranty or covenant hereunder or affect in any way any rights arising by virtue
of any prior or subsequent such occurrence.

             14. Severability. Any term or provision of this Agreement that is 
invalid or unenforceable

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<PAGE>

in  any situation  in  any  jurisdiction   shall  not  affect  the  validity  or
enforceability  of the remaining  terms and provisions  hereofor the validity or
enforceability  of the offending term or provision in any other  situation or in
any other jurisdiction.

                              EXSORBET INDUSTRIES, INC., 
                              an Idaho corporation "SELLER"


                              By: 
                              Title


                              AMERICAN PHYSICIAN SERVICE GROUP, INC.

                              a Texas corporation
                              "BUYER"

                              By: 

                              Title:



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<PAGE>

                                   EXHIBIT "A"
                             EXSORBET INDUSTRIES, INC.
                          REVENUE GENERATING SUBSIDIARY
                                  CORPORATIONS

Consolidated Environmental Services, Inc., an Arkansas corporation;

Cierra, Inc., an Arkansas corporation.;
Larco Environmental Services, Inc., a Louisiana corporation.;

KR Industrial Service of Alabama, Inc., an Alabama corporation at present;

Exsorbet Technical Services, Inc., an Arkansas corporation, dlb/a SpilTech 
Services, Inc.; and

Eco-Acquisition,  Inc., an Arkansas  corporation  (this company will be changing
its name to Eco-Systems, Inc.).

                    This   list   does  not   include   non-revenue   generating
subsidiaries of Exsorbet Industries, Inc.

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