<PAGE>

                                 EXHIBIT 2.07
 
                           STOCK PURCHASE AGREEMENT
                           ------------------------

      THIS STOCK PURCHASE AGREEMENT (the "Agreement") is made and entered into
as of the 10th day of July, 1996, by and among LAW COMPANIES GROUP, INC., a
Georgia corporation (the "Purchaser"), and certain owners of stock in
IAM/ENVIRONMENTAL, INC., a Texas corporation ("IAM/E, the "Company"), being: ROY
G. DIPASQUALE, JEFFREY A. STOCKS, JOHN M. JAZESF AND E. BRADFORD CLARK
(hereinafter individually referred to as "Seller," and collectively the
"Sellers").

     WHEREAS, the Sellers desire to sell, and the Purchaser desires to Purchase 
all of the shares of stock owned or held by the Sellers in the Company and as 
identified on Exhibit A (the "Stock"), on the terms and subject to the 
              ---------
conditions set forth below, which would result in the Purchaser owning, as of 
Closing (as hereinafter defined), one hundred percent (100%) of the stock owned 
or held by Sellers in the Company; and

     WHEREAS, the Purchaser and Sellers wish to supersede any written or implied
Shareholders' Agreements (if any) as to the purchase or sale of Stock by Sellers
in the Company by the terms and conditions hereof;

     NOW, THEREFORE, in consideration of the mutual promises, covenants, and 
agreements herein contained, the adequacy and sufficiency of which are hereby 
acknowledged, and $1.00 in hand paid to each Seller by Purchaser, the parties to
this Agreement do hereby promise, covenant, and agree as follows:

ARTICLE 1. THE TRANSACTION.

     1.1 PURCHASE OF SHARES.  Upon the terms of and subject to the conditions of
         ------------------
this Agreement, the Purchaser shall purchase from the Sellers, and the Sellers 
shall sell to the Purchaser, at the Closing (as hereinafter defined), the Stock,
in exchange for the Consideration (as hereinafter defined), subject in all 
instances to each of the terms, conditions, provisions, and limitations 
contained in this Agreement. At the Closing, (i) the Purchaser shall deliver to
the Sellers the Consideration; (ii) the Sellers shall deliver to the Purchaser 
all required certificates representing the stock, duly executed and accompanied 
by a stock power executed in blank; (iii) the Sellers shall execute and deliver 
to the Purchaser a Bill of Sale evidencing each transfer of Stock in 
substantially the form attached hereto as Exhibit B.
                                          ---------

     1.2 CLOSING. The closing hereunder shall take place at such place and time 
         -------
as the Purchaser and Seller may reasonable agree (the "Closing") but in no event
later than July 12, 1996.

     1.3 CONSIDERATION. The aggregate purchase price for the Stock (the 
         -------------
"Consideration") shall be ONE DOLLAR AND NO CENTS ($1.00) per Seller, which 
shall be paid by the Purchaser.

     1.4 PHILIP ENVIRONMENTAL TRANSACTION. This Agreement is contingent upon 
         --------------------------------
completion and execution of the Asset Purchase Agreement by and between IAM/E
and Philip Environmental Services, Inc. In the event the Asset Purchase
Agreement is not consummated this Agreement shall be null and void and without
further effect.

                                       1
<PAGE>
 
ARTICLE 2. CONSENT TO TRANSFER.

     Each party hereto, by signing below, expressly consents to each disposition
of the Stock as described herein.

ARTICLE 3. INVESTMENT MATTERS.

     (a)    The Purchaser has sufficient knowledge and experience in business 
and financial matters to evaluate the Company, to evaluate the risk of an 
investment in the Company, to make an informed investment decision with respect 
thereto, and to protect the Purchaser's interest in connection with its purchase
of the Stock.

     (b)    The Purchaser, as majority and controlling shareholder of the 
Company, has had complete access to, and has received and reviewed, such 
financial information and records of the Company as the Purchaser deemed 
necessary, and the Company has made available to the Purchaser the opportunity 
to ask questions of, and to receive answers from, representatives of the Company
and to obtain additional information relative to the Company and the Purchaser's
investment therein.  All such materials and information requested by the 
Purchaser have been made available and examined by the Purchaser.

ARTICLE 4. REPRESENTATIONS & WARRANTIES.

     Each of the Sellers represents and warrants to the Purchaser that the Stock
represents all of their ownership interest in IAM/E, is fully paid and 
nonassessable and is owned by such Sellers free and clear of any lien, pledge, 
security interest or claim.

ARTICLE 5. RELEASE.

     In consideration of the mutual benefits to each party in connection with 
this Agreement, the Purchaser and the Sellers hereby release and forever 
discharge, and agree to hold harmless, each other, with respect to any claim, 
loss, liability, cost (including reasonable attorney fees) or damage arising on 
or prior to the date hereof and arising under or relating to the sale of Stock 
described herein, except for any such claim, loss, liability, cost (including 
reasonable attorney fees) or damage arising out of a breach of this Agreement.

ARTICLE 6. TERMINATION OF SHAREHOLDERS' AGREEMENT.

     Any Shareholders' Agreement as to Sellers (if any) is hereby automatically 
terminated effective as of the date of this Agreement as a result of this 
Transaction.

ARTICLE 7. NOTICES.

     Any notice, request, instruction or any other document to be given
hereunder by any party hereto to any other party shall be in writing and
delivered personally (including overnight courier or express mail service) or
sent by facsimile, telecopier or registered or certified mail, return receipt
requested, postage or fees prepaid,


                                       2

<PAGE>
 
     if to Purchaser to:        Law Companies Group, Inc.
                                Attention: Mr. Darryl B. Segraves, Esq.
                                General Counsel and Executive Vice President
                                3 Ravinia Drive, Suite 1830
                                Atlanta, Georgia 30346
                                Facsimile number: (770) 390-3289

     if to the Sellers to:      Mr. Roy G. DiPasquale
                                5222 Royal Walk
                                Houston, Texas 77069
         
                                Mr. Jeffrey A. Stocks
                                5064 Augusta Street
                                Houston, Texas 77007

                                Mr. John M. Jazesf
                                3906 Yellow Finch Lane
                                Tampa, Florida 33549

                                Mr. E. Bradford Clark
                                9602 Godstone
                                Spring, Texas 77379

or at such address for a party as shall be specified by like notice.

ARTICLE 8. AMENDMENTS AND WAIVERS.

     This Agreement may not be amended or otherwise modified without the written
consent of the parties hereto.

ARTICLE 9. MISCELLANEOUS.

     This Agreement is being delivered and is intended to be performed in the 
State of Georgia and shall be construed and enforced in accordance with and 
governed by the laws of such state, without giving effect to the principles of 
conflicts of laws. All disputes arising under or relating to this Agreement 
shall be submitted to arbitration at Atlanta, Georgia, United States of 
America, pursuant to the Commercial Arbitration Rules of the American 
Arbitration Association (the "AAA") and each party hereto consents to the 
jurisdiction of the AAA. All the terms of this Agreement shall be binding upon 
and inure to the benefit of and enforceable by the respective successors and 
assigns of the parties hereto. This Agreement is the entire agreement and 
understanding and supersedes all prior agreements and understandings between the
Purchaser, the Sellers and the Company with respect to the subject matters 
hereof. The headings in this Agreement are for convenience of reference only, 
and shall not limit or otherwise affect the meaning hereof. This Agreement may 
be executed simultaneously in two or more counterparts, each of which shall be 
deemed an original, but all of which together shall constitute one and the same 
instrument.

     IN WITNESS WHEREOF, the undersigned have caused this Agreement to be 
signed and sealed on the date first written above by their respective officer 
duly authorized.

                                       3
<PAGE>
 
                                       PURCHASER:

                                       LAW COMPANIES GROUP, INC.


(SEAL)                                 By: /s/ Signature Appears Here
                                           ---------------------------
                                       Its:      EVP
                                           ---------------------------    

Attest: /s/ Signature Appears Here
        --------------------------------
Its:    Secretary

                                       SELLERS:

                                       /s/ Roy G. DiPasquale 
                                       -----------------------------(SEAL)
                                       Roy G. DiPasquale


                                    
                                       /s/ Jeffery A. Stocks
                                       -----------------------------(SEAL)
                                       Jeffrey A. Stocks





                                       -----------------------------(SEAL)
                                       John M. Jazosf




                                       /s/ E. Bradford Clark
                                       -----------------------------(SEAL)
                                       E. Bradford Clark




                                       4
<PAGE>
 
                                       PURCHASER:

                                       LAW COMPANIES GROUP, INC.


{SEAL}                                 By:
                                           -------------------------------

                                       Its:
                                           -------------------------------

Attest:
       --------------------------------
Its:    Secretary

                                       SELLERS:


                                       /s/ Roy G. DiPasquale
                                       -----------------------------------{SEAL}
                                       Roy G. DiPasquale



                                       /s/ Jeffery A. Stocks
                                       -----------------------------------{SEAL}
                                       Jeffery A. Stocks




                                       -----------------------------------{SEAL}
                                       John M. Jazesf



                                       /s/ E. Bradford Clark
                                       -----------------------------------{SEAL}
                                       E. Bradford Clark

<PAGE>
 
 
                                       PURCHASER:

                                       LAW COMPANIES GROUP, INC.


{SEAL}                                 By:
                                           -------------------------------

                                       Its:
                                           -------------------------------

Attest:
       --------------------------------
Its:    Secretary

                                       SELLERS:



                                       -----------------------------------{SEAL}
                                       Roy G. DiPasquale




                                       -----------------------------------{SEAL}
                                       Jeffery A. Stocks



                                       /s/ John M. Jazesf
                                       -----------------------------------{SEAL}
                                       John M. Jazesf




                                       -----------------------------------{SEAL}
                                       E. Bradford Clark