EXHIBIT 2.5









                            STOCK PURCHASE AGREEMENT

                                      among

                                     EMCON,
                            a California corporation
                                   ("EMCON"),

                        Organic Waste Technologies, Inc.
                             a Delaware corporation
                                   ("Buyer"),

                          NATIONAL EARTH PRODUCTS, INC.
                           a Pennsylvania corporation
                                (the "Company"),

                                       and

                       CERTAIN STOCKHOLDERS OF THE COMPANY
                                   ("Sellers")


                              Dated April 30, 1997





                                       43
<PAGE>






                                TABLE OF CONTENTS

Page
1.       Definitions........................................................  1
         "Agreement"........................................................  1
         "Best Efforts".....................................................  1
         "Breach"...........................................................  2
         "Buyer"............................................................  2
         "Buyer's Disclosure Statement" ....................................  2
         "CERCLA"...........................................................  2
         "Closing"..........................................................  2
         "Closing Date".....................................................  2
         "Code"............................................................   2
         "Common Shares"....................................................  2
         "Company"..........................................................  2
         "Company Financial Statements".....................................  2
         "Consent"..........................................................  2
         "Contemplated Transactions"........................................  3
         "Damages"..........................................................  3
         "Employee Plans"...................................................  3
         "Employment Agreements"............................................  3
         "ERISA"............................................................  3
         "Exchange Act".....................................................  3
         "Family"...........................................................  3
         "GAAP".............................................................  4
         "Governmental Authorization".......................................  4
         "Governmental Body"................................................  4
         "Hazardous Substances".............................................  4
         "IRS"..............................................................  4
         "Knowledge"........................................................  4
         "Knowledge of the Company".........................................  4
         "Legal Requirement"................................................  5
         "Material Contracts"...............................................  5
         "Material Interest.................................................  5
         "Notes"............................................................  5
         "Order"............................................................  5
         "Ordinary Course of Business"......................................  5
         "Person"...........................................................  5
         "Proceeding".......................................................  5
         "Purchase Price"...................................................  5
         "Related Person"...................................................  5
         "Representative"...................................................  6
         "Securities Act"...................................................  6
         "Sellers"..........................................................  6
         "Sellers' Disclosure Schedule".....................................  7

                                       44
<PAGE>

2.       Sale, Transfer and Exchange of Shares and Options; Closing.......  7
         2.1      Sale and Exchange.......................................  7
         2.2      Purchase Price..........................................  7
         2.3      Closing.................................................  8
         2.4      Closing Obligations.....................................  8
         2.5      Employment Agreement.................................... 10
         2.6      Employment Agreement.....................................10

3.       Representations and Warranties of the Company.................... 10
         3.1      Corporation Organization................................ 10
         3.2      Capitalization.......................................... 11
         3.3      Corporate Authority..................................... 11
         3.4      Dissolution; Forfeiture................................. 12
         3.5      The Company Financial Statements........................ 12
         3.6      Absence of Unaccrued or Undisclosed Liabilities......... 12
         3.7      Absence of Certain Changes.............................. 13
         3.8      Taxes................................................... 13
         3.9      Title to Properties; Accounts Receivable................ 14
         3.10     Proprietary Rights...................................... 15
         3.11     Customer Lists.......................................... 16
         3.12     Benefit Plans and Arrangements.......................... 16
         3.13     Compliance with Laws; Legal Proceedings................. 17
         3.14     Contracts and Obligations .............................. 18
         3.15     Employee Relations...................................... 19
         3.16     Insurance............................................... 19
         3.17     Environmental Compliance................................ 19
         3.18     Advances; Related Party Transactions.................... 20
         3.19     Powers of Attorney...................................... 21
         3.20     No Brokers.............................................. 21
         3.21     Other Agreements to Sell the Company.................... 21
         3.22     Banking Relationships................................... 21
         3.23     Ownership of Shares and Options......................... 22
         3.24     Execution, Delivery and Enforceability of Agreement; 
                  No Violation............................................ 22
         3.25     Information Supplied.................................... 23
         3.26     Residence and Domicile.................................. 23

4.       [Reserved]

5.       Representations and Warranties of Buyer and EMCON................ 23
         5.1      Organization and Good Standing.......................... 23
         5.2      Execution, Delivery and Enforceability of Agreement;
                  No Violation............................................ 23
         5.3      Investment Intent....................................... 24
         5.4      Certain Proceedings..................................... 24
         5.5      Brokers or Finders...................................... 24
         5.6      Information Supplied.................................... 24


                                       45
<PAGE>

         5.7      No Material Change..................................... 24

6.       Covenants of the Sellers Prior to Closing Date.................. 24
         6.1      Conduct of Business Pending Closing.................... 24
         6.2      Advice of Changes...................................... 26
         6.3      Access and Information................................. 26
         6.4      Reasonable Efforts..................................... 27
         6.5      Supplements to Company Disclosure Schedule............. 27

7.       Covenants of Buyer Prior to Closing Date........................ 27
         7.1      Access to Information.................................. 27
         7.2      Approvals of Governmental Bodies....................... 27
         7.3      Supplements to Schedules............................... 28
         7.4      Best Efforts........................................... 28
         7.5      Advice of Changes...................................... 28

8.       Conditions Precedent to Buyer's Obligation to Close............. 28
         8.1      Accuracy of Representations............................ 28
         8.2      Material Changes....................................... 29
         8.3      Sellers' and the Company's Performance................. 29
         8.4      Consents............................................... 29
         8.5      Additional Documents................................... 29
         8.6      No Proceedings......................................... 30
         8.7      Sellers Disclosure Schedule............................ 30
         8.8      Execution by Sellers................................... 30
         8.9      Employment Agreement................................... 30
         8.10     Notes.................................................. 30
         8.11     Release of Suretyship Agreement.........................30

9.       Conditions Precedent to Sellers' Obligation to Close............... 30
         9.1      Accuracy of Representations............................... 31
         9.2      Approval of this Agreement by Board of Directors.......... 31
         9.3      Buyer's Performance....................................... 31
         9.4      Consents.................................................. 31
         9.5      No Material Adverse Change................................ 31
         9.6      Buyer's Disclosure Schedule............................... 31
         9.7      Additional Documents...................................... 31
         9.8      No Proceedings............................................ 32
         9.9      Execution................................................. 32
         9.10     Employment Agreements..................................... 32
         9.11     Indebtedness of the Company............................... 32

10.      Covenants After the Closing Date................................... 32
         10.1     Litigation Support........................................ 32
         10.2     NEP Sand & Gravel Receivable.............................. 32
         10.3     Mining License............................................ 32


                                       46
<PAGE>

         10.4     S Corporation Matters................................... 32

11.      Termination...................................................... 33
         11.1     Termination Events...................................... 33
         11.2     Effect of Termination................................... 34

12.      Survival Remedies................................................ 35
         12.1     Survival................................................ 35
         12.2     Limitation of Liability..................................35

13.      General Provisions............................................... 39
         13.1     Expenses................................................ 39
         13.2     Public Announcements.................................... 39
         13.3     Confidentiality......................................... 39
         13.4     Notices................................................. 40
         13.5     Binding Arbitration; Service of Process................. 41
         13.6     Further Assurances...................................... 42
         13.7     Waiver.................................................. 42
         13.8     Entire Agreement and Modification....................... 42
         13.9     Sellers' Disclosure Schedule............................ 43
         13.10    Assignments, Successors, and No Third Party Rights...... 43
         13.11    Severability............................................ 43
         13.12    Section Headings, Construction.......................... 43
         13.13    Interpretation of Agreement..............................43
         13.14    Time of Essence......................................... 44
         13.15    Governing Law........................................... 44
         13.16    Counterparts............................................ 44


Exhibit No.                Document

A                          List of Management Stakeholders

B-1                        Convertible Promissory Note to Dennis Grimm
B-2                        Convertible Promissory Note to Charles Gearhart

C-1                        Employment Agreement of Dennis Grimm
C-2                        Employment Agreement of Charles Gearhart

D                          Certain Pre-Closing Employee Bonuses


                                       47
<PAGE>






                            STOCK PURCHASE AGREEMENT


         THIS STOCK PURCHASE AGREEMENT (the "Agreement") is made as of April 30,
1997  among  EMCON,   a  California   corporation   ("EMCON"),   ORGANIC   WASTE
TECHNOLOGIES,  INC.,  a  Delaware  corporation  ("Buyer"),  and  a  wholly-owned
subsidiary of EMCON; NATIONAL EARTH PRODUCTS,  INC., a Pennsylvania  corporation
(the "Company"),  and the undersigned  selling  shareholders of the Company (the
"Sellers").


                                    RECITALS

     A. The  Sellers  desire to sell and Buyer  desires to buy all of the Common
Shares of the  Company,  held by the  Sellers  and set forth on Exhibit A hereto
(such Common Shares  representing all of the equity interest in the Company) for
the consideration and on the terms set forth in this Agreement.

                                    AGREEMENT

     The parties, intending to be legally bound, agree as follows:

     1.  Definitions.  For the purposes of this  Agreement,  the following terms
have the meanings specified or referred to in this Section 1:

                  "Agreement" -- as defined in the first paragraph hereof.

                  "Best Efforts" -- the efforts that a prudent  Person  desirous
of achieving a result  would use in similar  circumstances  to maximize,  to the
extent reasonably practicable, the prospects that a result will occur; provided,
however,  that an obligation to use Best Efforts under this  Agreement  does not
require that the Person subject to such  obligation take such actions that would
result in a  material  adverse  change to the  benefits  to such  Person of this
Agreement and the Contemplated Transactions.

                  "Breach"  --  a  "Breach"  of  a   representation,   warranty,
covenant,  obligation  or other  provision of this  Agreement or any  instrument
delivered pursuant to this Agreement will be deemed to have occurred if there is
or has been any material  inaccuracy in or breach of, or any material failure to
perform or comply with, such representation,  warranty,  covenant or obligation,
and the term "Breach" means any such inaccuracy, breach or failure.

                  "Buyer" -- as defined in the first paragraph hereof.

                  "Buyer's  Disclosure  Schedule"  --  the  disclosure  schedule
delivered by the Buyer to the Company  prior to the Closing and attached  hereto
and made a part hereof, as required by Section 5, below.

                  "CERCLA" -- as defined in Section 3.17.


                                       48
<PAGE>

                  "Closing" -- as defined in Section 2.4.

                  "Closing  Date" -- the date and time as of which  the  Closing
actually takes place.

                  "Code" -- the Internal  Revenue Code of 1986,  as amended,  or
any successor  law, and  regulations  issued by the IRS pursuant to the Internal
Revenue Code or any successor law.

     "Common  Shares" -- the issued or issuable  shares of the Company's  common
stock.

                  "Company" --  as defined in the first paragraph hereof.

                  "Company Financial Statements" -- as defined in Section 3.5.

                  "Consent" -- any approval,  consent,  ratification,  waiver or
other authorization (including any Governmental Authorization).

     "Contemplated Transactions" -- all of the transactions contemplated by this
Agreement, including:

     (a) the sale to Buyers of the Common Shares held by the Sellers;

     (b) the execution,  delivery and performance of the Employment  Agreements,
the Escrow Agreement, the Note Agreement and the Notes; and

     (c) the performance by Buyer,  the Company and Sellers of their  respective
covenants and obligations under this Agreement.

     "Damages" -- as defined in Section 12.2.

     "Employee Plans" -- as defined in Section 3.12.

     "Employment Agreements" -- as defined in Sections 2.5 and 2.6.

                  "ERISA" -- the Employee Retirement Income Security Act of 1974
or any successor law, and  regulations  and rules issued pursuant to that Act or
any successor law.

                  "Exchange Act" -- the  Securities  Exchange Act of 1934 or any
successor law, and the  regulations or rules issued  pursuant to such Act or any
successor law.

     "Family" -- as defined in the definition of "Related Person."

                  "GAAP"  --  generally   accepted   United  States   accounting
principles,  applied on a basis consistent with the basis on which the financial
statements referred to in Section 3.5 were prepared.


                                       49
<PAGE>

                  "Governmental   Authorization"   --  any  approval,   consent,
license,  permit,  waiver  or  other  authorization  issued,  granted,  given or
otherwise made available by or under the authority of any  Governmental  Body or
pursuant to any Legal Requirement.

                  "Governmental Body"  --  any

     (a)  nation,  state,  county,  city,  town,  village,   district  or  other
governmental jurisdiction of any nature;

     (b) federal, state, local, municipal, foreign or other government;

     (c) governmental or  quasi-governmental  authority of any nature (including
any governmental agency, branch, department, official or entity and any court or
other tribunal);

     (d) multi-national organization or body; or

     (e)  body  exercising,   or  entitled  to  exercise,   any  administrative,
executive,  judicial,  legislative,  police,  regulatory or taxing  authority or
power of any nature.

                  "Hazardous Substances" -- as defined in Section 3.17.

                  "IRS" -- the United  States  Internal  Revenue  Service or any
successor agency,  and, to the extent relevant,  the United States Department of
the Treasury.

     "Knowledge" -- a Person will be deemed to have  "Knowledge" of a particular
fact or other matter if:

     (a) such individual is actually aware of such fact or other matter; or

     (b) a prudent  individual could be expected to discover or otherwise become
aware of such fact in carrying out such individual's duties for the Company.

     "Knowledge  of the  Company"  -- shall  mean  Knowledge  of any  officer or
director of the Company about the affairs of the Company.

     "Legal  Requirement"  -- any federal,  state,  local,  municipal,  foreign,
international, multinational or other constitution, law, ordinance, principle of
common law, regulation, statute or treaty.

     "Material Contracts" -- as defined in Section 3.14.

     "Material Interest" -- as defined in the definition of "Related Person."

                  "Notes" -- as defined in Section 2.2(b).


                                       50
<PAGE>

                  "Order" -- any award, decision,  injunction,  judgment, order,
directive, ruling, decree, subpoena or verdict entered, issued, made or rendered
by any  court,  administrative  agency,  or  other  Governmental  Body or by any
arbitrator.

                  "Ordinary  Course of  Business" -- an action taken by a Person
will be deemed to have been taken in the "Ordinary  Course of Business"  only if
such action is consistent with the past practices of such Person and is taken in
the ordinary course of the normal day-to-day operations of such Person.

                  "Person"  --  any  individual,   corporation   (including  any
non-profit  corporation),  general or  limited  partnership,  limited  liability
company, joint venture, estate, trust, association, organization or other entity
or Governmental Body.

                  "Proceeding"  --  any  action,  arbitration,  audit,  hearing,
investigation,  litigation or suit  (whether  civil,  criminal,  administrative,
investigative or informal) commenced,  brought, conducted or heard by or before,
or otherwise involving, any Governmental Body or arbitrator.

     "Purchase Price" -- as defined in Section 2.2.

     "Related Person" -- with respect to a particular individual:

     (a) each other member of such individual's Family;

     (b) any Person that is directly or indirectly controlled by any one or more
members of such individual's Family;

     (c)  any  Person  in  which  members  of  such  individual's   Family  hold
(individually or in the aggregate) a Material Interest; and

     (d)  any  Person  with  respect  to  which  one or  more  members  of  such
Individual's Family serves as a director,  officer, partner, executor or trustee
(or in a similar capacity).

With respect to a specified Person other than an individual:

     (a) any Person  that  directly  or  indirectly  controls,  is  directly  or
indirectly controlled by, or is directly or indirectly under common control with
such specified Person;

     (b) any Person that holds a Material Interest in such specified Person;

     (c) each Person that serves as a director,  officer, partner,  executor, or
trustee of such specified Person (or in a similar capacity);

     (d) any Person in which such  specified  Person holds a Material  Interest;
and

                                       51
<PAGE>

     (e) any Person  with  respect to which such  specified  Person  serves as a
general partner or a trustee (or in a similar capacity).

For purposes of this definition,  (a) the "Family" of an individual includes (i)
the individual, (ii) the individual's spouse, (iii) any other natural person who
is related to the individual or the individual's  spouse within the first degree
and (iv) any other  natural  person who resides  with such  individual,  and (b)
"Material Interest" means direct or indirect beneficial ownership (as defined in
Rule 13d-3 under the  Securities  Exchange Act of 1934) of voting  securities or
other  voting  interests   representing  at  least  ten  percent  (10%)  of  the
outstanding  voting  power of a Person  or  equity  securities  or other  equity
interests  representing  at least ten percent  (10%) of the  outstanding  equity
securities or equity interests in a Person.

                  "Representative"  -- with respect to a particular  Person, any
director, officer, employee, agent, consultant, advisor, or other representative
of such Person, including legal counsel, accountants, and financial advisors.

                  "Securities  Act"  --  the  Securities  Act  of  1933  or  any
successor  law, and  regulations  and rules  issued  pursuant to that Act or any
successor law.

                  "Sellers"  --  as defined in the first paragraph hereof.

                  "Sellers  Disclosure  Schedule"  --  the  disclosure  schedule
delivered by the Sellers to Buyer prior to the Closing and  attached  hereto and
made a part hereof as required by Section 3 below.

                  2.       Sale, Transfer and Exchange of Shares; Closing.

                           2.1      Sale and Exchange.

     (a) At the Closing,  the Sellers shall sell and transfer to Buyer and Buyer
shall purchase from the Sellers,  the Common Shares held by such Sellers and set
forth opposite their names on Exhibit A hereto.

     2.2  Purchase  Price.  The  purchase  price  for the  Common  Shares  being
purchased shall be paid as follows:

     (a) At the  Closing,  Buyer  shall pay the  Sellers  cash in the  aggregate
amount of  $860,789.81  by wire  transfer  ($431,253.98  to Dennis M.  Grimm and
$429,535.83 to Charels H. Gearhart).

     (b) At the Closing, Buyer shall deliver to Sellers EMCON's promissory notes
in the forms attached  hereto as Exhibit B-1 and B-2 in the aggregate  principal
amount of $800,000 (the "EMCON  Notes").  The EMCON Notes shall bear interest at
the rate of 8% per annum, simple interest, payable quarterly, with all principal
and any unpaid  interest  due and payable in full at maturity  (May 1, 2000 with
respect to the EMCON Note held by Dennis  Grimm and May 1, 2002 with  respect to
the EMCON Note held by Charles  Gearhart).  The  principal  balance of the EMCON
Notes shall be  convertible,  in part or in full, into EMCON Common Stock at the
election of the holders at a conversion rate of $6.50 per share.


                                       52
<PAGE>

     (c) The Sellers shall be entitled to receive an earn out from Buyer tied to
the  financial  performance  of the  Company in each of the three  twelve  month
periods  immediately  following  the Closing (the "Annual Earn Out") as follows:
The aggregate Annual Earn out shall equal 50% of Company's pre-tax profit earned
above the  following  base amounts for each twelve month period from May 1, 1997
through April 30, 2000:

                  Twelve Month Period                Pre-Tax Profit

                  05/01/97 - 04/30/98                   $500,000
                  05/01/98 - 04/30/99                   $550,000
                  05/01/99 - 04/30/00                   $600,000

     (i)   Calculation  of  the  Company's   pre-tax  profits  for  purposes  of
calculating  the Annual Earn Out shall be based on the  application of Generally
Accepted  Accounting  Principles,  consistently  applied,  including  the use of
accrual  accounting.  Until April 30, 2000,  without the consent of the Sellers:
(A)  neither  EMCON nor OWT  shall  allocate  any  portion  of their  respective
corporate overhead to the Company for purposes of the above earnout calculation.
(that  notwithstanding,  to the extent either EMCON or OWT incurs expenses (e.g.
insurance,  outside legal,  etc.) directly for the benefit of the Company,  such
amounts shall be charged to the Company for purposes of such  calculation),  (B)
EMCON and Buyer shall  operate the Company in the  ordinary  course of business,
consistent  with the  Company's  past  practices,  (C) EMCON and Buyer shall not
cause or permit the Company to engage in any  fundamental  transaction,  such as
merger,  consolidation,  sale of substantially  all of the Company's  assets, or
sale of stock,  (D) for  purposes  of the earnout  calculation,  EMCON and Buyer
shall not allocate any acquisition costs or expenses related to the transactions
contemplated  by this  Agreement to the Company  (including  without  limitation
interest  expense on funds used to acquire the Common Shares),  (E) for purposes
of the earnout  calculation,  EMCON and Buyer shall not  allocate  any  goodwill
amortization,   where  such  goodwill   arose   pursuant  to  the   transactions
contemplated by this Agreement, (F) for purposes of the earnout calculation, any
tax-sharing  payments made by the Company to EMCON, Buyer or a Related Person of
EMCON and Buyer shall be considered  tax payments (and not deducted from pre-tax
profits) even though such payments are made to EMCON,  Buyer or a Related Person
of EMCON and Buyer and (G) for purposes of the earnout calculation, the interest
cost of any funds loaned to NEP by EMCON  and/or OWT for any purpose,  including
but not limited to paying off the existing NEP bank lines,  shall be included as
an expense of NEP.

     2.3 Closing. The closing of the purchase, sale and exchange (the "Closing")
provided for in this Agreement will take place at the offices of Kegel, Chesters
& Miller, LLP, 24 North Lime Street, Lancaster, Pennsylvania effective the close
of business on April 30, 1997, or at such other date and time as may be approved
in writing by the parties hereto.

      2.4 Closing Obligations. At the Closing:

                                       53
<PAGE>

     (a) The Sellers, will deliver to Buyer:

     (i) certificates  representing the Common Shares held by the Sellers , duly
endorsed (or accompanied by duly executed stock powers), for transfer to Buyer;

     (ii) a  certificate  executed  by  each  of the  Sellers  representing  and
warranting to Buyer that each of the  representations  and warranties by him, or
it in this  Agreement  was accurate in all  material  respects as of the date of
this Agreements and is accurate in all material  respects as of the Closing Date
as if made on the Closing  Date (giving  full effect to any  supplements  to the
Sellers'  Disclosure  Schedule that were delivered by the Company to Buyer prior
to the Closing Date in accordance with Section 6.5); and

     (iii) such other  documents  as are  required  to be  provided  pursuant to
Section 8; and

     (b) Buyer will deliver to each Seller:

     (i) the  amount to be paid to each  Sellers at the  Closing  as  determined
pursuant  to Section 2.2 above.  Such  amounts  shall be paid by bank  cashier's
check payable to each Seller.

     (ii) a certificate  executed by Buyer  representing  and warranting to each
Seller that each of Buyer's representations and warranties in this Agreement was
accurate  in all  material  respects  as of the  date of this  Agreement  and is
accurate  in all  material  respects  as of the  Closing  Date as if made on the
Closing Date (giving full effect to any  supplements  to any schedules that were
delivered,  pursuant  to this  Agreement,  by the  Buyer to the  Sellers  or the
Company prior to the Closing Date in accordance with Section 7.3);

     (iii) such other  documents  as are  required  to be  provided  pursuant to
Section 9;

     2.5 Grimm Employment Agreement.  Concurrently herewith,  Dennis Grimm shall
execute and deliver an  employment  agreement  with the Company and EMCON in the
form  attached  hereto  as  Exhibit  C-1  (the  "Grimm  Employment  Agreement"),
including the commitment of EMCON to grant an incentive stock option to purchase
10,000 shares of EMCON Common Stock at an exercise  price per share equal to the
closing sales price of EMCON's Common Stock on the Closing Date.

     2.6 Gearhart Employment Agreement.  Concurrently herewith, Charles Gearhart
shall execute and deliver an employment  agreement with the Company and EMCON in
the form attached hereto as Exhibit C-2. (the "Gearhart  Employment  Agreement")
"),  including  the  commitment  of EMCON to grant an incentive  stock option to
purchase  10,000  shares of EMCON  Common  Stock at an exercise  price per share
equal to the closing sales price of EMCON's Common Stock on the Closing Date.

                                       54
<PAGE>

     3. Representations and Warranties of the Sellers. The Sellers each, jointly
and  severally  represent  and warrant to Buyer,  as of the Closing  Date,  that
except as set forth on the Sellers' Disclosure Schedule:

     3.1 Corporation Organization.

     (a) The Company is a corporation,  duly incorporated,  validly existing and
in good standing  under the laws of the State of  Pennsylvania.  The Company has
all requisite  corporate  power to own,  operate and lease its properties and to
conduct its business as now being  conducted.  The Company is duly  qualified or
licensed to do business,  and is in good standing as a foreign  corporation,  in
each state or other  jurisdiction in which it owns or leases properties or where
the  nature  of its  business  or  operations  requires  such  qualification  or
licensing,  unless the failure to do so would not have a material adverse effect
on the  Company's  assets,  business,  operations  or financial  condition.  The
Company  has  obtained  all  approvals,   authorizations,   consents,  licenses,
clearances and orders of, and has currently  effective all  registrations  with,
all governmental and regulatory authorities that are necessary to the conduct of
its business or operations as now being  conducted,  except where the failure to
do so would not have a material adverse effect on the Company.

     3.2 Capitalization.

     (a) The authorized  capital stock of the Company  consists solely of 10,000
shares of common stock, no par value. There are currently issued and outstanding
501  shares of common  stock;  all of which are held by the  Sellers  and listed
beside  their  names  on  Exhibit  A  attached  hereto.  All of the  issued  and
outstanding  shares of the Company are duly  authorized,  validly issued,  fully
paid and  nonassessable  except where failure to be so would not have a material
adverse effect on the business,  financial  position or operating results of the
Company.  All such  shares  have been  issued in  accordance  with  federal  and
applicable  state  securities  laws  concerning the issuance of securities.  The
rights,  preferences and privileges of the Company's capital stock are as stated
in the Company's Articles of Incorporation and Bylaws as heretofore amended.

     (b) Except as otherwise set forth in the Sellers' Disclosure  Schedule,  no
options,  warrants,  conversion  privileges,  preemptive rights, rights to first
refusal or other rights, agreements or commitments (written or otherwise) by the
Company are currently  outstanding  to purchase or otherwise  receive any of the
capital stock of the Company.

     (c) The Sellers have delivered to the Buyer complete and accurate copies of
the Articles of Incorporation and Bylaws  (including all amendments  thereto) of
the Company.  The Company has  delivered to the Buyer copies of the minute books
of the Company  containing  minutes for all  meetings  of, and written  consents
issued by the Company and  executed  by, the  Company's  stockholders,  Board of
Directors and all committees of such Board since the date of organization of the
Company.

 
                                       55
<PAGE>

     3.3 Corporate Authority.  The Company has all requisite corporate authority
and power to  execute  and  deliver  this  Agreement  and the  other  agreements
referenced  herein and to perform  all of its  obligations  with  respect to the
Contemplated  Transactions.  The  execution,  delivery and  performance  of this
Agreement and the other agreements referenced herein and the consummation of the
transactions contemplated hereby and thereby have been duly authorized, or prior
to the Closing will be duly authorized, by the Company's Board of Directors and,
if required, by its stockholders.

     3.4  Dissolution;  Forfeiture.  No action  at law or in  equity  and to the
Knowledge of the Sellers,  no  investigation  or  proceeding,  whatsoever is now
pending or threatened to: (a) liquidate, dissolve or disincorporate the Company,
(b) declare any of the corporate rights, powers or privileges of the Company, to
be null and void or  otherwise  than in full force and effect,  (c) declare that
the Company,  or the Boards of Directors  or any of their  respective  officers,
agents or employees has exceeded or violated any of their  respective  corporate
rights, powers or privileges, or (d) obtain any decree, order, judgment or other
judicial  determination  or  administrative  or other ruling that would or might
impede or detract from any of the corporate  rights,  powers or  privileges  now
vested in or claimed by the Company.

     3.5 The Company Financial Statements. The consolidated financial statements
of the Company for the fiscal years ended  September  30, 1995 and September 30,
1996 and the six (6) month period ended March 31, 1997 (the  "Company  Financial
Statements")  have been prepared in accordance with GAAP and fairly present,  in
all material respects,  the financial position of the Company in accordance with
GAAP as at the dates thereof.

     3.6 Absence of Unaccrued  or  Undisclosed  Liabilities.  Except for claims,
liabilities or  obligations  as provided for in the following,  the Company does
not  have  any  material  liabilities  whether  absolute,   accrued,  unaccrued,
contingent or otherwise whether due or to become due:

     (a) which were  properly  reflected or adequately  reserved  against in the
balance sheet included as part of the Financial Statements;

     (b) which were incurred in the Ordinary Course of Business since March
31, 1997;

     (c) which are listed on the Sellers' Disclosure Schedule; or

     (d) which are less than $10,000 in any single case;

     Except as set forth in paragraphs  (a) through (d) of this Section 3.6, the
Sellers do not have  Knowledge of and have no reasonable  grounds to know of any
basis for any assertion against the Company of any material claims,  liabilities
or  obligations  of any nature  required by GAAP to be  reflected in a corporate
balance  sheet which have not been fully  reflected  or reserved  against in the
Financial  Statements;  provided,  however, that no limitation set forth in this
Section  3.6  shall in any way  affect  any  other  representation  or  warranty
contained in this Agreement.

                                       56
<PAGE>

     3.7  Absence of Certain  Changes.  Since  March 31, 1997 there has not been
any:  (a)  material  adverse  change in the  business,  financial  condition  or
operations of the Company,  (b)  recapitalization,  amendment to the Articles of
Incorporation or Bylaws or any change in, authorization,  creation,  issuance or
agreement for issuance of, the capital stock or any securities convertible into,
or options, warrants or other rights to subscribe to any shares of capital stock
of the Company,  or any declaration  setting aside or payment of any dividend or
distribution  (whether in cash,  securities or property)  with respect  thereto,
except as  contemplated  hereby,  (c)  increase in the  compensation,  direct or
indirect,  payable to any of the officers or employees of the Company, including
adoption  of or  increase  in any bonus,  insurance,  pension or other  employee
benefit plan, payment or arrangement, or any other agreement or arrangement with
its officers,  employees or  stockholders,  except as contemplated  hereby,  (d)
unwaived default in respect of any Material Contracts, except for such defaults,
if any, which do not have a material  adverse effect on the financial  position,
business or operating results of the Company, (e) material change in the methods
and  procedures  employed in keeping the books and records of the Company or (f)
strike or labor dispute.

     3.8 Taxes.  All tax  returns of the  Company  required  by law  (including,
without   limitation,   all   income,   unemployment   compensation,    worker's
compensation,  Social Security,  excise, privilege and franchise tax laws of the
United States or any state or municipal subdivision thereof) to be filed through
the Closing Date (true and complete  copies of which have been  delivered to the
Buyer) have been or will be duly and timely filed,  and all taxes,  assessments,
contributions,  fees  and  governmental  charges  or  impositions  shown on said
returns or reports (other than those not yet due and payable or payable  without
penalty or interest) have been paid,  except where any failure to so file or pay
would,  individually or in the aggregate,  have a material adverse effect on the
Company, taken as a whole. The Company has not received any notice of assessment
of any  federal,  state,  municipal  or other tax upon or measured by its income
and, to the Sellers' knowledge,  there is no basis for an additional  assessment
of any such tax, except for those for which the Company has established adequate
reserves.  The Company has not knowingly waived any law or regulation fixing, or
consented to the extension of, any period of time for the  assessment of any tax
or other  governmental  imposition,  or become  committed so to do. There are no
audits of the Company pending and there are no matters under discussion with any
federal,  state, local or foreign  authorities with regard to the payment of any
taxes by the  Company.  There are no issues  that have been raised by the IRS or
other taxing  authority in connection  with an examination or otherwise which by
application of similar  principles  could  reasonably be expected to result in a
proposed deficiency for any period not examined.

     3.9 Title to Properties; Accounts Receivable.

     (a) Except for  property and assets that the Company has disposed of in the
Ordinary Course of Business, the Company has, and will have at the Closing Date,
good and  marketable  title to all properties and assets shown or represented on
the  balance  sheet  included  as part of the Company  Financial  Statements  or
acquired since March 31, 1997, free and clear of all mortgages,  pledges, liens,
defects in title, conditional sale agreements and other encumbrances, except for


                                       57
<PAGE>

liens, encumbrances and defects in title in respect of property or assets of the
Company which: (i) are incidental to the conduct of the Company's business; (ii)
have  arisen in the  Company's  Ordinary  Course  of  Business;  (iii)  were not
incurred in connection  with the borrowing of money or the obtaining of advances
or credit (other than credit arrangements  related to purchase money liens); and
(iv) do not in the aggregate  materially detract from the property and assets of
the  Company.  The  Company has  performed  all the  obligations  required to be
performed by it with respect to all assets leased by it through the date hereof,
except where the failure to perform would not have a material  adverse effect on
the business or financial condition of the Company.  The Company enjoys peaceful
and undisturbed possession of all of its offices, warehouses,  buildings and all
other real property and related  facilities,  whether owned,  leased or operated
(collectively,  the  "Facilities"),  and,  except as otherwise  set forth in the
Sellers'  Disclosure  Schedule,  such  Facilities are not subject to any claims,
liens, pledges, options, charges, easements, security interests,  rights-of-way,
encumbrances   or  other  rights,   or  any   encroachments,   building  or  use
restrictions,  exceptions,  reservations  or  limitations  which in any material
respect  interfere  with or impair the present and  continued use thereof in the
usual and normal  conduct of its  business.  There are no pending or to Sellers'
Knowledge threatened condemnation proceedings relating to any of the Facilities.
The  Facilities  and  the  real  property   improvements   (including  leasehold
improvements),  equipment and other tangible assets owned or used by the Company
at the Facilities are insured in amounts  believed by the Sellers to be adequate
and, are structurally sound with no material defects. Said items are not subject
to any commitment or other  arrangement  for their sale by the Company or use by
third  parties  other  than  commitments  or  arrangements  entered  into in the
Ordinary Course of Business. The assets are valued at or below the lower of fair
market value or actual cost less an adequate and proper depreciation charge. For
tax purposes,  the Company has not  depreciated  any of the assets in any manner
inconsistent with applicable IRS guidelines, if any.

     (b) All  tangible  property,  real and  personal,  owned or  leased  by the
Company is in reasonable  operating  condition  and repair,  except for ordinary
wear and tear and any  defects  the cost of  repairing  which,  singly or in the
aggregate,  would not be material  or are  accrued for on the Company  Financial
Statements.  The Company has  operated  such  property  in  conformity  with all
applicable laws, ordinances,  orders, regulations,  rules and other requirements
(including applicable zoning, environmental,  motor vehicle safety or standards,
occupational  safety and health laws and  regulations)  currently  in effect and
relating thereto,  except where the failure to conform would not have a material
adverse  effect  on the  business,  operations  or  financial  condition  of the
Company.

     (c) All accounts  receivable of the Company shown on the Company  Financial
Statements are valid,  genuine and  subsisting,  arose in the Ordinary Course of
Business,  and the  aggregate  amount  thereof  less the  reserve  for  doubtful
accounts  with respect  thereto set forth in the Company  Financial  Statements,
are, to the Knowledge of the Sellers,  current and collectible  within customary
payment terms.

     (d) The Company did not perform a title search or purchase title  insurance
on the three properties on which it has license  agreements,  namely,  the Moll,
Hinton  and  Baker  Refractories  properties.  As a  consequence,  Sellers  take
exception for title defects in the respective  owner's title to such  properties
for those title  defects of record or visible on the  property;  provided  that,
Sellers  represent  that  they  have no actual  knowledge,  without  independent
investigation,  of any such  defects  which have  adversely  affected,  or could
adversely affect, the Company's operations on such properties.


                                       58
<PAGE>

                           3.10     Proprietary Rights.

     (a) The Company owns the rights to use all trademarks, trade secrets, trade
names, copyrights,  processes, designs, formulas, know-how, inventions, licenses
and  intellectual  property  rights used in connection with its business and the
same are believed by the Sellers to be sufficient to conduct such business as it
is now or heretofore has been conducted with no known or asserted  conflict with
or infringement of the asserted or actual rights of others.  The Sellers have no
Knowledge of any  infringement  by any third party in connection with any of the
foregoing  and  neither the Sellers nor the Company has taken or omitted to take
any action  which would have the effect of waiving any of the  Company's  rights
thereunder, in each case except where such infringement or waiver would not have
a material adverse effect on the business,  prospects,  condition  (financial or
otherwise)  or results of  operations  of the Company.  To the  Knowledge of the
Sellers, no third party has filed or been issued or granted any applications for
patents,  trademarks,  trade  names or  registered  copyrights  relating  to the
Company's assets.

     (b)  The  Sellers'   Disclosure   Schedule   lists  all   patents,   patent
applications,  trademarks,  trade names and registered  copyrights  owned by the
Company. Except as set forth in the Sellers' Disclosure Schedule, the Company is
not required to pay any royalty,  license fee or similar type of compensation in
connection  with the conduct of its business as it is now or heretofore has been
conducted.

     (c) The Company has obtained  written  agreements from all required parties
and entities  assigning to the Company any material  proprietary rights relating
to the Company's  assets.  Such agreements are currently valid and in full force
and effect and except as set forth in the Sellers' Disclosure  Schedule,  do not
contain any provisions or restrictions  with regard to the rights granted to the
Buyer  under this  Agreement  All  material  trade  secrets of the  Company  are
currently  protectable  and are not part of the public  knowledge or literature,
nor have they been used,  divulged,  or appropriated for the benefit of any past
or present employees or other persons, or to the detriment of, the Company.

     3.11  Customer  Lists.  The Company has  provided  the Buyer a complete and
accurate  list  of  each  of  the  material   customers  of  the  Company.   The
relationships between the Company and its active customers and suppliers are, in
the aggregate,  in good standing, and since March 31, 1997, no material customer
or supplier has canceled or  terminated,  or, to the  Knowledge of the Sellers,,
threatened to cancel,  terminate or change its relationship  with the Company in
any manner adverse to the Company.

                           3.12     Benefit Plans and Arrangements.

     (a)  Except  as  set  forth  in the  Sellers'  Disclosure  Schedule,  or as
otherwise  contemplated by this Agreement,  the consummation of the Contemplated
Transactions  will not  result  in any  payment  (whether  of  severance  pay or
otherwise)  becoming due from the Company to any  employee,  consultant or other
third party.


                                       59
<PAGE>

     (b) The Sellers' Disclosure Schedule lists all pension,  retirement,  stock
purchase,  stock option, stock bonus, savings or profit sharing plan, individual
employment  agreement,  bonus  or  incentive  compensation  programs,   deferred
compensation  agreements,  severance  pay  plans,  consultant,  bonus,  or group
insurance  contracts,  or any other  material  incentive,  welfare  or  employee
benefit  plan,  or  similar  arrangement,  understanding  or course of  dealing,
including  all employee  benefit  plans and employee  pension  benefit  plans as
defined in Section 3(3) of ERISA (the "Employee Plans").

     (c) With respect to the Employee  Plans,  the Company has delivered or made
available to the Buyer copies of any: (1) plans and related trust  documents and
amendments thereto;  (ii) the most recent summary plan descriptions and the most
recent annual report; (iii) annual reports on Form 5500 which were filed in each
of the most recent  three (3) plan years,  including,  without  limitation,  all
schedules  thereto  and all  financial  statements  with  attached  opinions  of
independent  accountants;  (iv) Form PBGC-1  which was filed in each of the most
recent three (3) plan years; (v) the most recent actuarial  valuation;  and (vi)
the most recent  determination  letter  received  from the IRS.  Such  financial
statements  fairly  present the  financial  condition of each  Employee  Plan in
accordance with United States generally accepted  accounting  principles applied
on a consistent  basis. All Employee Plans have been administered in substantial
compliance  with  their  terms,  ERISA  to the  extent  applicable,  and,  where
applicable, Section 401 of the Code.

     (d) No event of the type set forth in Section 4043(b) of ERISA has occurred
and is continuing with respect to Employee Plans except insofar as such an event
may arise as a result of the  consummation of the  Contemplated  Transactions or
would not have a material adverse effect upon the Company's business,  financial
position or operating results.  There exists no material violation of ERISA with
respect to the filing of reports,  documents, and notices regarding the Employee
Plan participants or beneficiaries.  No action,  suit, or proceeding is pending,
nor, to the  Knowledge  of the Company,  is any  threatened  or  imminent,  with
respect  to the  assets  of any of the  trusts  under  any  Employee  Plan.  All
amendments required to bring an Employee Plan into conformity, in all applicable
and material respects, with ERISA have been made. Any bonding with respect to an
Employee Plan required under ERISA is in full force and effect.  The Company has
not incurred any liability,  pursuant to Subtitle A of Title IV of ERISA, to the
Pension Benefit Guaranty Corporation.

     (e) No breach of fiduciary  responsibility has occurred with respect to any
of the  Employee  Plans other than such breach,  if any,  which would not have a
material  adverse  effect  on the  Company's  business,  financial  position  or
operating  results.  There is no suit,  litigation  or claim (other than routine
benefit claims) pending or, to the Knowledge of the Sellers,  threatened against
the Company or any fiduciary of any Employee Plan involving any Employee Plan or
against  any such plan or its  assets by any  employee  or former  employee  (or
beneficiary thereof) of the Company which individually or in the aggregate would
adversely affect the financial condition of any such Employee Plan.

                                       60
<PAGE>

                           3.13     Compliance with Laws; Legal Proceedings.

     (a) The Company is not in violation  of, or in default with respect to, any
term or provision of (i) its Articles of  Incorporation  or Bylaws,  or (ii) any
judgment,  writ,  order,  injunction,  or decree of any court or of any federal,
state,  or municipal  agency or authority  in any case or  proceeding  expressly
naming the Company.

     (b) The  Company  and its  operations  are in  compliance  with  applicable
statutes,  ordinances,  regulations,  requirements  and  orders  of the  federal
government and of all states,  municipalities,  and agencies thereof, and of all
other  authorities  having  jurisdiction  in  respect  of any of its  assets  or
operations (including any applicable foreign government or agency or subdivision
thereof),  except  where the failure to do so would not have a material  adverse
effect on the Company.

     (c) The  Company  has  not  been  threatened  with,  nor is it a party  to,
directly or indirectly,  nor, to the Knowledge of the Sellers,  is there any set
of facts that is likely to give rise to, any material legal action, governmental
investigation,   or  other  proceeding  (governmental  or  private),   including
investigations,  inquiries, citations, complaints, orders or stipulations by any
federal, state or local agency or governmental unit, and there are no judgments,
orders,  restrictions or decrees of a continuing nature outstanding  against the
Company.  The Company has not been threatened with, nor, to the Knowledge of the
Sellers  is there  any set of facts  that is likely to give rise to, a charge of
any material  violation of any provision of any federal,  state,  local or other
law  (including  common law), or  administrative  regulations  in respect of its
business or property.

     3.14 Contracts and Obligations. The Sellers' Disclosure Schedule sets forth
a true and complete list of the following  agreements  and  instruments to which
the Company is a party: (a) all executory contracts,  agreements and instruments
having  a total  contract  price  in  excess  of  $25,000;  (b)  all  contracts,
agreements or instruments which are in the nature of teaming  agreements,  joint
venture agreements,  non-compete  agreements,  franchise  agreements,  exclusive
license  agreements  or  other  similar  agreements  restricting  access  to any
business   opportunity  of  the  Company;  (c)  all  loan  or  debt  agreements,
guarantees,  indemnities and bonding commitments;  (d) all license or technology
transfer agreements;  (e) all leases,  subleases and equipment leases,  having a
total  contract  price in excess of  $25,000;  (f) all  agreements  between  the
Company,  on the one hand, and any of the officers,  directors or  stockholders;
(g) all material  agreements between the Company, on the one hand, and any other
employees of the Company on the other hand; (h) all material licenses or permits
issued by any government agency or authority for the benefit of the Company; (i)
any  management  or  consultation  agreement  not  terminable  at  will  without
liability;  (j) any  contracts or  agreements  requiring  the payment of fees or
commissions  in  connection  with  any sale of all or  substantially  all of the
Company's stock or assets or any sale of a substantial  interest in the Company;
and (k) any other agreement  which  materially  affects the Company's  business,
financial  position or operating results or which was entered into other than in
the Ordinary Course of Business  (collectively,  the "Material Contracts").  The
Company  has  delivered  to the Buyer  true and  complete  copies of each of the
Material  Contracts.  The Company is not in material violation of, or in default

                                       61
<PAGE>

with respect to, any Material  Contract  and the Material  Contracts  are valid,
binding and enforceable,  subject only to applicable bankruptcy,  insolvency and
similar  laws  affecting   creditors  rights   generally  and  subject,   as  to
enforceability,  to general principles of equity. The relationships  between the
Company  and the other  parties  to each of the  Material  Contacts  are in good
standing,  and no such other  contract  party has  canceled  or  terminated,  or
threatened to cancel,  terminate or change in any manner  adverse to the Company
such relationship or the terms of any Material Contract.

                           3.15     Employee Relations.

     (a) The  Company  has no  union or  collective  bargaining  agreement,  any
contract or other agreement with any labor  organization or with any employee or
consultant  which is not terminable at will by the Company,  without  liability,
and no such  contract or  agreement is under  discussion  by  management  of the
Company with any employee or consultant.  There are no pending or threatened (i)
strikes,  work  stoppages,  slowdowns or picketing  respecting  employees of the
Company,  (ii) unfair labor practice  complaints  against the Company,  or (iii)
statutes, contracts or agreements,  domestic or foreign, which will obligate the
Company to make any severance payments as a consequence of the execution of this
Agreement or the consummation of the Contemplated Transactions.

     (b) The Company has not received  notice that there is any key employee who
intends to leave the Company's  employ as a result of, or at the  conclusion of,
the Contemplated Transactions. The Company's relationship with its employees, on
the whole, is consistent within industry norms.

     3.16  Insurance.  The  properties  and risks of the  Company are covered by
valid and currently effective insurance policies issued in favor of the Company,
which  policies  are set  forth on the  Sellers'  Disclosure  Schedule,  and the
Company is included as an insured party under such policies, with full rights as
loss  payee.  The  Sellers'  Disclosure  Schedule  contains  a  list  and  brief
description  of each  insurance  policy  (copies of which  have been  previously
provided  to the  Buyer)  maintained  with  respect  to  the  Company  (or  such
corporation's  assets or operations),  which provides  continuing coverage as of
the date hereof. The Sellers' Disclosure Schedule also includes a list and brief
description of individual claims in excess of $10,000 now pending or made during
the 36-month period immediately  preceding the date of this Agreement,  by or on
behalf of the Company under any insurance policies.

                           3.17     Environmental Compliance.

     (a) The Company has all material permits, licenses and other authorizations
required under applicable laws and regulations relating to pollution control and
protection of the environment necessary for the operation of its Facilities. The
Company is not in material  violation of any of the terms or  conditions  of any
such permits, licenses, leases, or authorizations.  The Company has not acted or
failed to act in violation of any law or regulation,  order or other requirement
of  governmental  authorities  with respect to the pollution of the  atmosphere,
surface water,  groundwater and noise,  the handling of toxic or hazardous waste
material or other matters related to the  environment.  There are no pending or,
to the Knowledge of the Sellers,  threatened civil or criminal actions,  notices
of violations or  administrative  proceedings  relating to pollution  control or
protection of the environment  that would have a material  adverse effect on the
business or financial condition of the Company.

                                       62
<PAGE>

     (b) There are no material conditions, circumstances, activities, practices,
incidents,  actions or plans which would be reasonably  likely to interfere with
or  prevent  compliance  or  continued   compliance  by  the  Company  with  any
environmental  laws  currently in force or with any existing  regulation,  code,
order, decree,  judgment,  injunction,  notice or demand letter issued, entered,
promulgated or approved thereunder,  or which may give rise to any common law or
other  legal  liability,  including  without  limitation,  liability  under  the
Comprehensive Environmental Response,  Compensation and Liability Act ("CERCLA")
or similar  state,  foreign or local laws,  or  otherwise  form the basis of any
claim, action, demand, suit, proceeding,  hearing, notice of violation, study or
investigation of or against the Company, based on or related to the manufacture,
processing,  distribution,  use,  treatment,  storage,  disposal,  transport  or
handling,  or the emission,  discharge,  release or threatened  release into the
workplace or the environment by the Company, or to the Company's  Knowledge,  by
any other third party, of any pollutant,  contaminant,  chemical, or industrial,
toxic or  hazardous  material,  substance  or waste on any  properties  owned or
leased  by, or under the direct  control  of,  the  Company.  Without in any way
limiting the foregoing, no release,  emission or discharge to the environment of
any hazardous substance (as that term is currently defined under CERCLA or under
any applicable analogous state law ("Hazardous Substance") by the Company, or to
the Company's  Knowledge,  by any other third party has occurred or is currently
occurring  in  connection  with any action or  failure to act on any  properties
owned or leased by, or under the direct  control  of, the  Company  which has or
could give rise to any liability of the Company.

                           3.18     Advances; Related Party Transactions.

     (a)  There  are no  receivables  of the  Company  owing  by any  directors,
officers,  employees or  consultants  of the Company or to any  affiliate of any
such  Company  person or  entity,  other  than  advances  by the  Company in the
ordinary course of business to officers and employees for reimbursable  business
expenses.

     (b) No stockholder,  officer,  director or employee of the Company, nor any
member of the Family of any such  stockholder,  officer,  director  or  employee
owns, or has owned, directly or indirectly,  any interest exceeding five percent
(5%) in (a) any  business,  corporate or other,  which is material  party to any
material  business  arrangement with the Company or (b) any material property or
rights,  tangible  or  intangible,  used  in the  business  of the  Company.  No
stockholder,  officer, or director of the Company, owns, directly or indirectly,
any  interest in, or is an officer or director  of, any  business,  corporate or
other (other than as a stockholder of a public company), which competes with the
Company.

     3.19  Powers of  Attorney.  The  Sellers'  Disclosure  Schedule  contains a
complete   list  of  all  powers  of  attorney   (or  similar   instruments   or
authorizations)  granted by the Company to any person or entity. All such powers
of  attorney  (or  similar   instruments  or  authorizations)   are  subject  to
termination  or  revocation  by the Company at any time,  without  notice to any
other person or entity and without penalty.

                                       63
<PAGE>

     3.20 No Brokers.  Neither  the Company nor the Sellers has entered  into or
will enter into any contract,  agreement or understanding with any Person, which
may result in the  obligation  of the  Company or the Buyer to pay any  finder's
fee, brokerage commission or similar payment in connection with the Contemplated
Transactions

     3.21 Other Agreements to Sell the Company.  Except as set forth herein, the
Company has no legal obligation,  absolute or contingent,  to any person or firm
to sell any capital stock of the Company or to effect any merger,  consolidation
or other reorganization,  or disposition of all or substantially all the assets,
of the Company.

     3.22 Banking Relationships.  The Sellers' Disclosure Schedule correctly and
completely  lists all banks and  accounts in such banks,  with which the Company
has deposits,  indicating  the names of those  authorized to sign documents with
respect to such  accounts as of the date of the most recently  approved  banking
resolution with respect to each.

     3.23  Ownership of Shares and Options.  Except as set forth in the Sellers'
Disclosure  Schedule,  the Sellers own of record and  beneficially the number of
Common Shares indicated opposite each such Seller's name in Exhibit A hereto, as
applicable,  with full right and authority to sell or exchange,  as  applicable,
such securities  hereunder,  and upon delivery of such Common Shares  hereunder,
the Buyer will  receive  good title  thereto,  free and clear of all  mortgages,
pledges  or  security   interests   and  not  subject  to  any   agreements   or
understandings  among any Persons with respect to the voting or transfer of such
securities other than those arising under agreements to which Buyer is a party

     3.24 Execution,  Delivery and  Enforceability  of Agreement;  No Violation.
This  Agreement  has been duly  executed  and  delivered  by or on behalf of the
Company  and each  Seller,  and at the  Closing  any  other  documents  required
hereunder to be executed  and  delivered by or on behalf of the Company and each
Seller will have been duly executed and delivered.  This  Agreement  constitutes
the  legal,  valid  and  binding  obligation  of the  Company  and each  Seller,
enforceable  against the Company and each Seller in  accordance  with its terms,
except as  enforcement  may be limited  by  applicable  bankruptcy,  insolvency,
reorganization,  fraudulent  conveyance,  moratorium  or  other  laws  affecting
creditor's  rights  generally.   Any  other  agreements  or  documents  required
hereunder to be executed and delivered by the Company and each Seller at Closing
will constitute the legal,  valid and binding agreements of the Company and each
Seller  executing the same,  enforceable  against the Company and each Seller in
accordance with their respective terms,  except as enforcement may be limited by
applicable  bankruptcy,  insolvency,   reorganization,   fraudulent  conveyance,
moratorium or other laws  affecting  creditor's  rights  generally.  Neither the
execution  of  this  Agreement  nor  the   consummation   of  the   Contemplated
Transactions  by the  Company  and each Seller will  violate,  or  constitute  a
default under,  or permit the  acceleration of maturity of, except to the extent
waived, any indentures,  mortgages, promissory notes, contracts or agreements to
which the  Company and each Seller is a party or by which the Company and Seller
or the Company and each Seller's properties are bound.

     3.25 Information  Supplied.  To the Knowledge of the Sellers,  neither this
Agreement,  the Company Financial Statements,  the Sellers' Disclosure Schedule,
the Exhibits  attached to this Agreement,  nor any other certificate or document
furnished or to be furnished by the Company or the Sellers pursuant to the terms
of this Agreement,  contains or will contain any untrue  statement of a material
fact  known  to the  Sellers  or omits or will  omit to  state a  material  fact
necessary to make the statements contained in such information not misleading in
light of the circumstances under which such statements were made.

 
                                       64
<PAGE>

     3.26  Residence and  Domicile.  The Sellers are residents of, and domiciled
in,  the  States  indicated  on Exhibit A hereto,  as  applicable,  as being the
residence of each such Seller.

                  4.       [Reserved]

                  5.  Representations  and Warranties of Buyer and EMCON.  Buyer
and EMCON  jointly  and  severally  represent  and  warrant to  Sellers  and the
Company, as of the date hereof and except as set forth in the Buyer's Disclosure
Schedule, as follows:

     5.1 Organization and Good Standing.  Buyer and EMCON are corporations  duly
organized,  validly existing,  and in good standing under the laws of the States
of Delaware and California, respectfully.

     5.2 Execution, Delivery and Enforceability of Agreement; No Violation. This
Agreement  has been duly executed and delivered by or on behalf of the Buyer and
EMCON, and at the Closing any other documents  required hereunder to be executed
and  delivered  by or on  behalf  of the  Buyer  and  EMCON  will have been duly
executed and delivered.  This Agreement constitutes the legal, valid and binding
obligation  of the  Buyer  and  EMCON,  enforceable  against  Buyer and EMCON in
accordance  with its terms,  except as enforcement  may be limited by applicable
bankruptcy,  insolvency,  reorganization,  fraudulent conveyance,  moratorium or
other laws affecting creditor's rights generally.  Any other agreements required
hereunder  to be executed  and  delivered by the Buyer and EMCON at Closing will
constitute  the  legal,  valid and  binding  agreements  of the Buyer and EMCON,
enforceable against the Buyer and EMCON in accordance with its respective terms,
except as  enforcement  may be limited  by  applicable  bankruptcy,  insolvency,
reorganization,  fraudulent  conveyance,  moratorium  or  other  laws  affecting
creditor's  rights  generally.  Neither the execution of this  Agreement nor the
consummation of the transactions provided for herein by the Buyer and EMCON will
violate,  or constitute a default under, or permit the  acceleration of maturity
of, except to the extent waived,  any indentures,  mortgages,  promissory notes,
contracts or  agreements to which such  respective  party is a party or by which
such  respective  party or its properties are bound.  Except as set forth in the
Buyer's Disclosure Schedule, Buyer and EMCON are not and will not be required to
obtain any Consent from any Person in connection with the execution and delivery
of this Agreement or the  consummation or performance of any of the Contemplated
Transactions.

     5.3  Investment  Intent.  Buyer is  acquiring  the Common  Shares  from the
Sellers for its own account and not with a view to their distribution within the
meaning of Section 2.11 of the Securities Act. Buyer is a sophisticated business
entity,  experienced  in the business of the Company and is able to evaluate the
merits and risks of acquiring the Common Shares.

                                       65
<PAGE>

     5.4  Certain  Proceedings.  There is no  pending  Proceeding  that has been
commenced  against  Buyer or EMCON  that  challenges,  or may have the effect of
preventing,  delaying, making illegal, or otherwise interfering with, any of the
Contemplated  Transactions.  To Buyer's  Knowledge,  no such Proceeding has been
threatened.

     5.5 Brokers or Finders.  Buyer and its officers and agents have incurred no
obligation or liability, contingent or otherwise, for brokerage or finders' fees
or  agents'  commissions  or other  similar  payment  in  connection  with  this
Agreement.

     5.6  Information  Supplied.  The EMCON  Annual  Report on Form 10-K for the
fiscal year ending December 31, 1996, does not contain any untrue statement of a
material fact or omits to state a material fact necessary to make the statements
contained therein not misleading in light of the circumstances  under which such
statements were made.

     5.7 No Material Change. Since December 31, 1996, there has been no material
adverse  change in the  business,  financial  position or operations or Buyer or
EMCON.

                  6.       Covenants of the Sellers Prior to Closing Date.

     6.1 Conduct of Business  Pending  Closing.  Except as  contemplated by this
Agreement or otherwise agreed to by the Buyer in writing,  prior to Closing, the
Sellers hereby covenant and agree as follows:

     (a) The  Company  will  carry on its  business  in the  Ordinary  Course of
Business and,  without  limiting the generality of the foregoing,  (i) not sell,
assign, lease, pledge,  mortgage,  encumber or otherwise dispose of or grant any
preferential  rights in any of its assets,  or incur or become obligated to pay,
any  liabilities,  except in the Ordinary  Course of  Business,  (ii) not pay or
prepay  any  obligation  or  liability  (fixed,  contingent  or  otherwise),  or
discharge or satisfy any lien or  encumbrance,  or settle any liability,  claim,
dispute,  proceeding, suit or appeal, pending or threatened against it or any of
its assets or  properties,  except for the pay off of all long term debt owed to
William  Holbrook in the approximate  amount of $79,000 and current  liabilities
included in the Company Financial  Statements and current  liabilities  incurred
since March 31, 1997 in the Ordinary Course of Business or current  non-material
liabilities,  (iii) except for individual  expenditures  and commitments made in
the Ordinary Course of Business and involving amounts not exceeding $10,000, not
make any expenditure or commitment for the purchase,  acquisition,  construction
or  improvement  of a capital  asset,  (iv) use its Best  Efforts to continue in
effect all  existing  policies of  insurance  (or  comparable  insurance)  of or
relating to the Company,  (v) keep proper books of record and account  necessary
to prepare  financial  statements in accordance  with GAAP and (vi) not amend or
terminate any Material  Contract in a manner that would have a material  adverse
effect on the business,  financial  position or operating results of the Company
or amend  any  contract,  agreement  or  license  to which it is a party,  which
amendment  would make it a Material  Contract,  unless such amendment  would not
have a material adverse effect on the business, financial condition or operating
results of the Company and would not extend the term of such contract, agreement
or license by more than one year.


                                       66
<PAGE>

     (b) No change  will be made in the  authorized  or issued  and  outstanding
capital stock of the Company, and the Company shall not issue or commit to issue
any option, warrant, note, bond or other security convertible into shares of the
Company's capital stock.

     (c)  Except  as set forth on  Exhibit  D, no  increase  will be made in the
compensation  payable  or to  become  payable  by  the  Company  to  any  of its
directors,  officers, employees, agents, consultants or stockholders,  including
any stock options, bonus payments or other benefits.

     (d) The  Company  will not  effect  or agree to  effect  any  amendment  or
supplement to, or extension of, any Employee Plan.

     (e) The Company will not acquire any equity  securities or similar interest
in any other  corporation,  association,  joint venture,  partnership,  business
trust or other business  entity,  or acquire the assets or liabilities of any of
the  foregoing,  or  merge,  consolidate  or  otherwise  combine  with any other
corporation or other business entity, or enter into any agreement  providing for
any of the foregoing.

     (f) The  Company  will not  enter  into or agree  to enter  into any  other
contracts,  licenses or other  transactions other than in the Ordinary Course of
Business and, without  limiting the generality of the foregoing,  not enter into
or agree to enter into any contracts, agreements or instruments which are in the
nature  of  joint  venture   agreements,   non-compete   agreements,   franchise
agreements, exclusive license agreements, or other similar agreements.

     (g) Except as required by currently existing  agreements,  the Company will
not  declare or pay any  dividend  on the  outstanding  shares of the  Company's
capital  stock in cash,  stock or property or redeem,  repurchase  or  otherwise
acquire any shares of the  Company's  capital  stock or enter into any agreement
providing for any of the foregoing.

     (h) The Company and the Sellers  will not solicit or initiate  proposals or
offers  from any  person  relating  to any  acquisition  or  purchase  of all or
substantially  all of the assets of, or any equity interest in, the Company,  or
any merger, consolidation,  business combination or similar transaction with the
Company, or participate in any negotiations  regarding,  or furnish to any other
person any confidential  information with respect to, or otherwise  cooperate in
any way with, or participate in, facilitate or encourage,  any effort or attempt
by any  other  person  to do or seek any of the  foregoing.  The  Company  shall
promptly  notify  the Buyer if any such  proposal  or offer,  or any  inquiry or
contact with any person with respect thereto, is made.

     (i) No change  will be made with  respect to the  banking  or safe  deposit
arrangements of the Company:

     (j) The Company will use its Best  Efforts to keep intact the  organization
of the  Company;  to  keep  available  the  services  of the  Company's  present
employees;  and to preserve the goodwill of its suppliers,  customers and others
having business relations with the Company; and

                                       67
<PAGE>

     (k) The  Company  will timely file all  required  material  tax returns and
promptly  pay all  federal,  state and local tax  assessments  and  governmental
charges lawfully levied or assessed upon it or upon its properties,  or upon any
part thereof,  which have become due and payable,  and the Company will withhold
from its  employee's  wages and pay over all federal and state taxes required to
be withheld and paid over.

     6.2 Advice of Changes. Prior to the Closing Date, the Company will promptly
advise the Buyer in writing of (i) any known event  occurring  subsequent to the
date of this Agreement which would render any  representation or warranty of the
Company contained in this Agreement, if made on and as of the date of such event
or the Closing Date, untrue or inaccurate in any material respect (other than an
event so affecting a representation  or warranty which is expressly limited to a
state of facts  existing at a time prior to the  occurrence of such event),  and
(ii)  any  material  adverse  change  in the  business,  financial  position  or
operating  results  of the  Company  occurring  subsequent  to the  date of this
Agreement.

     6.3 Access and Information. The Company will, at all reasonable times prior
to the Closing  Date and upon  reasonable  notice from Buyer,  open its offices,
books,  accounts and  records,  including  policies,  claims of  creditors,  and
obligations of the Company, and will, upon reasonable notice from Buyer, provide
free  access to the  Company's  management  to discuss  the  Company's  business
operations,  assets,  liabilities,  actual or potential  litigation  and claims,
properties  and  prospects,   to  working  papers,  files  and  records  of  its
accountants,  each for full and  unrestricted  examination and inspection by the
Buyer, its officers, attorneys or accountants.

     6.4  Reasonable  Efforts.  Subject  to  the  terms  and  conditions  herein
provided,  the Company and each Seller shall use his, her or its Best Efforts to
(a) cause to be fulfilled and satisfied all of the  conditions to the Closing to
be fulfilled  and  satisfied by him, her or it and (b) cause to be performed all
of the matters required of him, her or it at the Closing.

     6.5  Supplements to Sellers'  Disclosure  Schedule.  Sellers shall have the
right, from time to time, on or prior to the Closing, to supplement the material
set forth in the Sellers' Disclosure Schedule initially delivered by the Sellers
to Buyer. Any references to the Sellers'  Disclosure  Schedule in this Agreement
or in any other document  entered into in connection  with this Agreement  shall
mean the Sellers'  Disclosure  Schedule as fully amended and  supplemented on or
prior to the Closing Date.

                  7.       Covenants of Buyer Prior to Closing Date.

     7.1  Access to  Information.  Between  the date of this  Agreement  and the
Closing Date, Buyer will afford Sellers and their  Representatives full and free
access,  upon the request of Sellers,  to copies of EMCON's public filings under
the Securities Act, the Exchange Act, and other information as Sellers and their
Representatives shall reasonably request.

                                       68
<PAGE>

     7.2 Approvals of Governmental  Bodies. As promptly as practicable after the
date of this  Agreement,  Buyer will, and will cause each of its Related Persons
to,  make  all  filings  required  by Legal  Requirements  to be made by them to
consummate the Contemplated Transactions. Between the date of this Agreement and
the  Closing  Date,  Buyer  will,  and will  cause  each  Related  Person to (a)
cooperate  with Sellers with respect to all filings that Sellers are required by
Legal Requirements to make in connection with the Contemplated Transactions, and
(b) cooperate with Sellers in obtaining all consents  identified in the Sellers'
Disclosure Schedule.

     7.3  Supplements  to  Schedules.  Buyer shall have the right,  from time to
time, on or prior to the Closing,  to  supplement  the material set forth in any
schedule  initially  delivered  to the Company or the  Sellers  pursuant to this
Agreement.  Any references to the Buyer Disclosure Schedule in this Agreement or
in any other document  entered into in connection with this Agreement shall mean
such  schedules  as fully  amended and  supplemented  on or prior to the Closing
Date.

     7.4 Best Efforts.  Subject to the terms and conditions herein provided, the
Buyer and EMCON shall use their Best  Efforts to (a) cause to be  fulfilled  and
satisfied  by it  all of  the  conditions  to the  Closing  to be  fulfilled  or
satisfied by it and (b) cause to be performed all of the matters  required of it
at Closing.

     7.5 Advice of Changes.  Prior to the Closing Date,  the Buyer will promptly
advise all of the other  parties  hereto in  writing of (i) any event  occurring
subsequent to the date of this Agreement  which would render any  representation
or warranty of the Buyer and EMCON contained in this  Agreement,  if made on and
as of the date of such event or the Closing  Date,  untrue or  inaccurate in any
material respect (other than an event so affecting a representation  or warranty
which is expressly  limited to a state of facts  existing at a time prior to the
occurrence of such event),  and (ii) any material adverse change in the business
affairs of the Buyer occurring subsequent to the date of this Agreement.

     8. Conditions  Precedent to Buyer's Obligation to Close. Buyer's obligation
to purchase  the Common  Shares  from the Sellers and to take the other  actions
required to be taken by Buyer at the Closing is subject to the satisfaction,  at
or prior to the Closing,  of each of the following  conditions (any of which may
be waived by Buyer, in whole or in part):

     8.1 Accuracy of Representations. Each of the representations and warranties
in Section 3 of this Agreement, must have been accurate in all material respects
as of the date of this  Agreement and must be accurate in all material  respects
as of the Closing Date as if made on the Closing Date.

     8.2 Material  Changes.  There shall be no material  adverse  changes to the
business, financial condition or operating results of the Company since the date
of this Agreement.

     8.3 Sellers' and the Company's Performance.

                                       69
<PAGE>

     (a) All of the covenants and  obligations  that the Sellers and the Company
are required to perform or to comply with pursuant to this Agreement at or prior
to the  Closing  (considered  collectively),  and  each of these  covenants  and
obligations  (considered  individually),  must  have  been  duly  performed  and
complied with in all material respects.

     (b) Each Seller or the  Company,  as the case may be,  must have  delivered
each of the documents  required to be delivered by such Seller  pursuant  hereto
and each of the other  covenants and  obligations in required to be performed by
Seller or the Company must have been performed and complied with in all material
respects.

     8.4  Consents.  Each of the Consents  required to be obtained to consummate
the Contemplated  Transactions must have been obtained and must be in full force
and effect.

     8.5 Additional  Document.  Sellers must have caused the following documents
to be delivered to Buyer:

     (a)  resolution of the Boards of Directors of the Company  authorizing  the
Contemplated Transactions, certified by the Secretary of the Company;

     (b) certificates of good standing from the state of  incorporation  for the
Company as of a date no more than ten (10) days prior to the Closing Date.

     8.6 No Proceedings.  Since the date of this Agreement,  there must not have
been commenced or threatened in writing against Buyer or the Company, or against
any Person  affiliated  with Buyer or the Company,  any Proceeding (a) involving
any material  challenge to, or seeking material damages or injunctive  relief in
connection with, any of the Contemplated Transactions,  or (b) that may have the
effect of preventing,  delaying,  making illegal, or otherwise  interfering with
any of the Contemplated Transactions.

     8.7 Sellers'  Disclosure  Schedule.  The Sellers shall have provided  Buyer
full and complete and final copies of the  Sellers'  Disclosure  Schedule  which
shall reflect no material adverse changes in the Company's business or financial
condition from the date of this Agreement.

     8.8  Execution  by Sellers.  All of the Sellers  listed on Exhibit A hereto
shall have executed this Agreement.

     8.9 Employment  Agreement.  The Grimm Employment Agreement and the Gearhart
Employment Agreement shall be in full force and effect.

     8.10 Notes.  The EMCON Notes shall have been  executed and delivered by the
Buyer to the Sellers.

                                       70
<PAGE>

     8.11 Release of  Suretyship  Agreement.  The Company  shall have received a
release of all further obligations of the Company relative to NEP Sand & Gravel,
Inc., under that certain Suretyship Agreement dated as of April 8, 1996.

     9.  Conditions   Precedent  to  Sellers'  Obligation  to  Close.   Sellers'
obligations to sell their Common Shares,  and to take the other actions required
to be taken by Sellers at the  Closing  is  subject to the  satisfaction,  at or
prior to the Closing,  of each of the following  conditions (any of which may be
waived by Sellers).

     9.1  Accuracy  of  Representations.  All  of  Buyer's  representations  and
warranties in Section 5 must have been  accurate in all material  respects as of
the date of this  Agreement and must be accurate in all material  respects as of
the Closing Date as if made on the Closing Date.

     9.2 Approval of this  Agreement by Board of Directors.  This  Agreement and
the agreements  referenced herein must be approved by the Boards of Directors of
the Buyer and EMCON.

     9.3 Buyer's Performance.

     (c) All of the covenants and obligations  that Buyer is required to perform
or to comply with  pursuant to this  Agreement  at or prior to the Closing  must
have been performed and complied with in all material respects.

     (d) Buyer must have  delivered  each of the documents  (including the EMCON
Notes)  required to be  delivered by Buyer and EMCON and must have made the cash
payments required to be made by Buyer pursuant to Section 2.

     9.4  Consents.  Each of the Consents  required to be obtained to consummate
the Contemplated  Transactions must have been obtained and must be in full force
and effect.

     9.5 No Material  Adverse Change.  There shall have been no material adverse
change in Buyer's or EMCON's business,  financial condition or operating results
from the date of this Agreement.

     9.6 Buyer's Disclosure Schedule.  The Buyer shall have provided the Company
full and complete copies of Buyer's  Disclosure  Schedule which shall reflect no
material adverse changes in Buyer's or EMCON's business,  financial condition or
operating results from the date of this Agreement.

     9.7 Additional Documents.  Buyer and EMCON must have caused to be delivered
to Sellers:

     (a)  resolution  of  the  Boards  of  Directors  of  the  Buyer  and  EMCON
authorizing the Contemplated Transactions,  certified by the Secretary of Buyer;
and

                                       71
<PAGE>

     (b)  Certificates  of good standing for the Buyer and EMCON as of a date no
more than ten (10) days prior to the Closing Date.

     9.8 No Proceedings.  Since the date of this Agreement,  there must not have
been  commenced  or  threatened  in writing  against  Buyer,  the Company or any
Seller, or against any Person affiliated with Buyers, the Company or any Seller,
any  Proceeding  (a)  involving any material  challenge to, or seeking  material
damages  or  injunctive  relief  in  connection  with,  any of the  Contemplated
Transactions,  or (b) that may have the effect of preventing,  delaying,  making
illegal,  or otherwise  interfering with any of the  Contemplated  Transactions;
provided  however that this Section 9.9 may not be relied upon by the Company or
Sellers and this condition will be deemed to have been waived by the Sellers and
the Company if Buyer agrees to proceed to close  hereunder  and to indemnify the
Company and Sellers in full  against any damages  that may be incurred by reason
of any claim described in this Section.

     9.9  Execution.  The Sellers  listed on Exhibit A shall have  executed this
Agreement.

     9.10 Employment Agreements. The Grimm Employment Agreement and the Gearhart
Employment Agreement shall be in full force and effect.

     9.11.  Indebtedness of the Company. Buyer shall have arranged financing for
the  Company  such that as of the  Closing  Date,  all  corporate  and  personal
guarantees and suretyships of the Company's  indebtedness  shall be released and
discharged,  including  without  limitation,  the  suretyships  of the Company's
indebtedness  by Sellers and NEP Sand & Gravel,  Inc.  Buyer shall have arranged
for the  replacement of the two letters of credit issued by Dauphin Deposit Bank
and Trust  Company on behalf of the Company for the benefit of the  Pennsylvania
Department of Environmental  Protection,  in the amounts of $17,300 and $22,800.
Buyer shall have repaid indebtedness owed by the Company to William J. Holbrook,
in the amount at April 30, 1997 (after the scheduled  payment on April 15, 1997)
of approximately $72,249.99.

     10. Covenants After the Closing Date.

     10.1 Litigation Support. In the event and for so long as any party actively
is  contesting  or  defending  against any action,  suit,  proceeding,  hearing,
investigation, charge, complaint, claim, or demand in connection with:

     (a) any of the Contemplated Transactions; or

     (b)  any  fact,  situation,   circumstance,  status,  condition,  activity,
practice,  plan,  occurrence,   event,  incident,  action,  failure  to  act  or
transaction  on or prior to the Closing Date  involving  the  Company,  then the
other party shall  cooperate  with it and its counsel in the defense or contest,
make  available its personnel and provide such testimony and access to its books
and records as shall be necessary in connection with the defense or contest, all
at the sole cost and expense of the contesting or defending party.

 
                                       72
<PAGE>

     10.2 NEP Sand & Gravel  Receivable.  Contemporaneous  with the  anticipated
closing of the sale of NEP Sand & Gravel,  Inc. by the Sellers,  the outstanding
receivable  from NEP Sand & Gravel,  Inc.  to the Company  shall be  immediately
repaid in full.  In the event such  amount is not  repaid on or before  July 31,
1997, the amounts remaining  outstanding and unpaid from NEP Sand & Gravel, Inc.
shall be offset against and reduce,  on a pro rata basis, the principal  balance
of the EMCON Notes.

     10.3 Mining  License.  Explore,  Inc., a Pennsylvania  corporation of which
Sellers own  fifty-one  percent of the  outstanding  stock,  used the  Company's
mining license  number to apply for a mining permit to mine  dimension  stone at
the Clapsaddle Property.  Sellers expect that a mining permit for the Clapsaddle
Property will be issued in the Company's name. For a period of one year from the
Closing  Date (or  earlier  upon the sale or  discontinuance  of the  Clapsaddle
project),  Buyer shall cause the Company,  and the Company shall, allow Explore,
Inc.  to continue  using the  Company's  mining  license as  previously  used by
Explore,  Inc. and maintain the mining permit in the Company's name. The Company
shall,  and Buyer  agrees to cause the Company to,  cooperate  with  Sellers and
Explore,  Inc. (and take all steps reasonably  necessary or appropriate) to have
the permit issued in the Company's  name at no cost to the Company.  The Company
shall,  and Buyer agrees to cause the Company to,  transfer  (and take all steps
reasonably  necessary or  appropriate to transfer at no cost to the Company) the
mining permit to a person selected by Sellers.  Sellers  represent that Explore,
Inc.  will not  engage  in mining  activity  under the  mining  permit.  Sellers
represent that Explore, Inc.'s continued use of the Company's mining license and
the  issuance,  maintenance  and transfer of the mining  permit in the Company's
name shall not result in any cost or liability  to the Company.  In this regard,
Sellers  agree  to  indemnify   and  hold  harmless  the  Company   against  any
liabilities, damages, costs or expenses, arising from Explore, Inc.'s use of the
Company's  mining  license and the  issuance,  maintenance  and  transfer of the
mining permit in the Company's name.

     10.4 S Corporation Matters. Sellers, the Company and Buyer acknowledge that
upon the transfer of the Common  Shares by Sellers to Buyer,  the S  corporation
election  of the  Company  will  automatically  terminate  because  Buyer  is an
ineligible  shareholder for the valid continuation of S corporation  status. The
Sellers,  the Company and Buyer also  acknowledge  that  because more than fifty
percent  (50%) of the stock of the Company  stock will change  ownership  in the
current tax year,  under  I.R.C. ss  1362(e)(6)(D),  normal tax  accounting
methods,  and not a pro rata allocation,  will apply to the short S tax year and
short C tax year resulting from termination of the S corporation elections. Upon
execution of this  Agreement and  continuing  after the transfer,  Sellers,  the
Company and Buyer agree, without further  consideration,  to execute and deliver
promptly to the requesting party such further assignment, endorsement, and other
documents and instruments,  and to take all such further actions, as Seller, the
Company or Buyer may from time to time  reasonably  request  with respect to the
preparation  and  submittal  of tax  returns,  tax notices and other  documents,
including  without  limitation,  the  execution  and  delivery  of a consent  to
termination date of the S corporation election of the Company.

     10.5 Mountain View Job Bonus.  If the pre-tax  profit on [the Mountain View
Job]  exceeds  $60,000,  then  Buyer  shall  cause the  Company  to pay a $5,000
compensation bonus to Tim Hipps. In calculating  pre-tax profits on the Mountain
View Job, the Company  shall use the per job profit  calculation  method used by
the  Company  prior  to the  Closing  which  would  include,  for  example,  not
allocating administrative overhead to the Job.

                                       73
<PAGE>

                  11.      Termination.

     11.1 Termination  Event. This Agreement may also be terminated prior to the
Closing:

     (a) by written notice  delivered to the other parties hereto at or prior to
the Closing

     (i) by (A) Buyer if a Breach of any  provision of this  Agreement  has been
committed  by any Seller or by the Company or (B) the Company and the Sellers if
a Breach of any provision of this Agreement has been committed by the Buyer, and
such  Breach set forth in (A) or (B) has not been  waived,  or cured  within ten
(10) days after  receipt of written  notice of such Breach by the party  against
whom such Breach is alleged; or

     (ii) by the Buyer if the supplements to the Sellers'  Disclosure  Schedule,
disclose  a material  adverse  change in the  business,  financial  position  or
operating results of the Company, from that set forth on the Sellers' Disclosure
Schedule as delivered to the Buyer.

     (b) by written notice  delivered to the other parties hereto at or prior to
the Closing

     (i) by Buyer if any of the  conditions in Section 8 has not been  satisfied
as of the Closing  Date or if  satisfaction  of such a  condition  is or becomes
impossible  (other  than  through  the  failure  of  Buyer  to  comply  with its
obligations  under this Agreement) and Buyer has not waived such condition on or
before the Closing Date; or

     (ii) by Sellers  owning a majority of the Common Shares or the Company,  if
any of the conditions in Section 9 has not been satisfied as of the Closing Date
or if  satisfaction  of such a condition  is or becomes  impossible  (other than
through the  failure of Sellers or the Company to comply with their  obligations
under this Agreement) and Sellers and the Company have not waived such condition
on or before the Closing Date; or

     (c) by mutual consent of Buyer and the Sellers.

     11.2 Effect of Termination. Each party's right of termination under Section
11.1 in  addition  to any  other  rights it may have  under  this  Agreement  or
otherwise, and the exercise of a right of termination will not be an election of
remedies.  If this Agreement is terminated pursuant to Section 11.1, all further
obligations  and liabilities of the parties under this Agreement will terminate,
except as follows:

     (i) The obligations in Sections 13.1, 13.2 and 13.3 will survive;


                                       74
<PAGE>

     (ii) If this  Agreement is  terminated  by a party because of the Breach of
the  Agreement by another  party,  the  terminating  party's right to pursue all
legal remedies will survive such termination unimpaired.

                  12.      Survival; Remedies.

     12.1 Survival.  Notwithstanding any investigation conducted before or after
the  Closing  Date,  the  parties  hereto  will be  entitled  to rely  upon  the
representations  and  warranties of the other  parties  hereto set forth in this
Agreement  (as  modified  by each  party's  Disclosure  Schedule  attached as an
Exhibit to this Agreement). All representations and warranties in this Agreement
or in any  instrument  delivered  pursuant to this  Agreement  will  survive the
Closing.

     12.2 Limitation of Liability.  Sellers,  the Company,  EMCON or Buyer shall
have no liability with respect to a breach of this Agreement,  including without
limitation a breach of a representation,  warranty or covenant contained in this
Agreement,  until the total of all such  liabilities  against such party exceeds
$25,000  (provided  however,  that this  minimum  shall not apply to breaches of
Section 3.2 of this Agreement).  The parties agree that each Seller's  aggregate
liability with respect to his  breach(es) of this Agreement  shall be limited to
the purchase  price received by such Seller  pursuant to Section 2.2;  provided,
however,  that no such limitation of liability will apply to Damages incurred by
Buyer  or  EMCON  as  a  result  of  any   intentional   or  grossly   negligent
misrepresentation, action or failure to act by Seller(s).

     12.3 Survival.  Notwithstanding any investigation conducted before or after
the   Closing,   the   parties   hereto  will  be  entitled  to  rely  upon  the
representations  and  warranties of the other  parties  hereto set forth in this
Agreement.  All  representations  and  warranties  in this  Agreement  or in any
instrument  delivered pursuant to this Agreement will survive until the date one
(1) year after the Closing, at which time the representations and warranties set
forth in this  Agreement and all liability of the parties hereto with respect to
those  representations and warranties will terminate;  provided,  however,  that
thereafter a party hereto will remain liable with respect to any claim of breach
of a representation or warranty provided such claim has been asserted in writing
(specifying  in  reasonable  detail  the basis and  amount of such  claim) on or
before the date one (1) year after the Closing until such time as said claim has
been finally decided, settled, or adjudicated.

                  13.      General Provisions.

     13.1 Expenses.  Except as otherwise  expressly  provided in this Agreement,
each  party to the  Agreement  will bear  his,  her or its  respective  expenses
incurred in connection with the preparation,  execution, and performance of this
Agreement and the Contemplated Transactions,  including all fees and expenses of
agents, representatives, counsel, and accountants.

     13.2 Public  Announcements.  No party shall issue any press release or make
any public announcement related to the subject matter of this Agreement prior to
the  Closing  without the prior  written  approval of the Sellers and the Buyer;


                                       75
<PAGE>

provided,  however, that any party may make any public disclosure it believes in
good faith is required  by  applicable  law or any listing or trading  agreement
concerning  the  publicly-traded  securities  of such  party (in which  case the
disclosing  party will use its reasonable best efforts to advise the other party
prior to making the  disclosure  and consult with the other party  regarding the
content thereof).  The Sellers and Buyer will consult with each other concerning
the means by which the Company's  employees,  customers and suppliers and others
having  dealings  with  the  parties  will  be  informed  of  the   Contemplated
Transactions.

     13.3 Confidentiality. Between the date of this Agreement and five (5) years
after the date  hereof,  Buyer,  the  Company,  and  Sellers  will  maintain  in
confidence,  and will cause the  directors,  officers,  employees,  agents,  and
advisors of Buyer, the Company,  and the Sellers to maintain in confidence,  and
not  use to  the  detriment  of  another  party  any  written,  oral,  or  other
information  obtained in confidence  from another party in connection  with this
Agreement or the Contemplated  Transactions,  expressly including the reports of
all consultants  retained  pursuant to the terms of this  Agreement,  unless (a)
such information  becomes publicly available through no fault of such party, (b)
the use of such  information is necessary or appropriate in making any filing or
obtaining  any  consent  or  approval  required  for  the  consummation  of  the
Contemplated  Transactions,  or (c) the furnishing or use of such information is
required by legal proceedings.

     If the  Contemplated  Transactions  are not  consummated,  each  party will
return or destroy as much of such  written  information  as the party  providing
such information may reasonably request.

     13.4 Notices.  All notices,  consents,  waivers,  and other  communications
under this  Agreement  must be in  writing  and will be deemed to have been duly
given when (a) delivered by hand (with  written  confirmation  of receipt),  (b)
sent by telecopier (with written confirmation of receipt),  provided that a copy
is mailed  within three (3) business  days by registered  mail,  return  receipt
requested,  (c)  when  received  by  the  addressee,  if  sent  by a  nationally
recognized  overnight  delivery  service (receipt  requested),  or (d) three (3)
business days after being sent by registered or certified  mail,  return receipt
requested,  in each case to the appropriate addresses and telecopier numbers set
forth below (or to such other  addresses and  telecopier  numbers as a party may
designate by notice to the other parties):

          Sellers:        To each Seller at the address set forth on Exhibits A


          The Company:       National Earth Products, Inc.
                             245 Butler Avenue
                             Lancaster, PA  17601
                             Attn:  Charles Gearhart
                             Fax No.:  (717) 390-9896


                                       76
<PAGE>


          Buyer:             EMCON
                             400 S. El Camino Real, Suite 1200
                             San Mateo, California  94402
                             Attention:  R. Michael Momboisse, Esq.
                             Fax No.:  (415) 375-0763

                  13.5 Binding Arbitration;  Service of Process. In the event of
a dispute between the parties  related to or arising out of this Agreement,  the
Agents and representatives of the Buyer and the Company will meet promptly in an
effort to resolve the dispute  amicably.  If such  parties  cannot  agree upon a
resolution  within  thirty (30) days of any such party  requesting a meeting for
resolution  of a dispute,  then the matter will promptly be submitted to binding
arbitration in accordance with this Section 13.5.

     (a) Arbitration will be held in Philadelphia,  Pennsylvania,  in accordance
with the rules and  regulations  of the American  Arbitration  Association.  The
number of  arbitrators  will be one and will be selected in accordance  with the
rules and regulations of the American Arbitration Association. The determination
of the  arbitrator  will be  conclusive  and binding upon the  parties,  and any
determination  by the  arbitrator  of an award may be filed  with the clerk of a
court of competent  jurisdiction as a final  adjudication of the claim involved,
or  application  may be made to such court for judicial  acceptance of the award
and an order of enforcement,  as the case may be. Except to the extent otherwise
directed by the  arbitrator,  each party will bear its own  expenses,  including
legal and accounting fees, if any, with respect to the arbitration, and one-half
of  the  costs  of  the  arbitrator  and of the  fees  imposed  by the  American
Arbitration Association.

     (b)  In  any  arbitration  hereunder,  the  demand  for  arbitration  shall
specifically  delineate the claims asserted and the material issues with respect
thereto. Within thirty (30) days after filing a demand for arbitration, claimant
shall provide to respondent a list of all fact witnesses known to claimant,  the
names and curriculum  vitae of each expert  witness  anticipated to be called by
claimant,  and a copy of  relevant  documents.  Within  thirty  (30) days  after
receipt of the  foregoing  information,  respondent  shall provide to claimant a
list of all fact witnesses known to respondent,  the names and curriculum  vitae
of each expert witness  anticipated  to be called by  respondent,  and a copy of
relevant documents known to respondent. Within ten (10) days after discovery has
been closed by the arbitrator  (but in no event later than sixty (60) days prior
to the arbitration hearing),  claimant shall present to respondent a list of all
fact and expert witnesses anticipated to be called by claimant, a summary of the
substance  of  each  such  witness'  testimony,  and a  list  of  all  documents
anticipated  to be introduced  by claimant (and a copy of such  documents if not
previously provided to respondent). Within thirty (30) days after receipt of the
foregoing  information,  respondent shall present to claimant a list of all fact
and expert  witnesses  anticipated to be called by respondent,  a summary of the
substance  of  each  such  witness'  testimony,  and a  list  of  all  documents
anticipated to be introduced by respondent  (and a copy of such documents if not
previously  provided to claimant).  Any award by the arbitrator shall be subject
to all dollar and other limitations set forth in this Agreement.


                                       77
<PAGE>


     (c) A demand for arbitration may be served on Buyer or Sellers by certified
U.S. Mail,  postage prepaid,  or reliable  overnight  delivery  service,  to the
address set forth in Section 13.4 hereof.

                  13.6 Further Assurances. The parties agree (a) to furnish upon
request to each other such  further  information,  (b) to execute and deliver to
each other such other documents,  and (c) to do such other acts and things,  all
as the other party may  reasonably  request for the purpose of carrying  out the
intent of this Agreement and the documents referred to in this Agreement.

                  13.7  Waiver.  The rights and  remedies of the parties to this
Agreement are cumulative and not alternative.  Neither the failure nor any delay
by any party in exercising any right,  power,  or privilege under this Agreement
or the documents  referred to in this Agreement will operate as a waiver of such
right, power, or privilege, and no single or partial exercise of any such right,
power,  or privilege will preclude any other or further  exercise of such right,
power, or privilege or the exercise of any other right, power, or privilege.  To
the maximum  extent  permitted by applicable  law, (a) no claim or right arising
out of this  Agreement or the  documents  referred to in this  Agreement  can be
discharged by one party, in whole or in part, by a waiver or renunciation of the
claim or right unless in writing  signed by the other party;  (b) no waiver that
may be given by a party will be applicable  except in the specific  instance for
which it is given; and (c) no notice to or demand on one party will be deemed to
be a waiver of any  obligation of such party or of the right of the party giving
such  notice  or  demand  to take  further  action  without  notice or demand as
provided in this Agreement or the documents referred to in this Agreement.

                  13.8  Entire  Agreement  and   Modification.   This  Agreement
supersedes all prior agreements  between the parties with respect to its subject
matter and constitutes  (along with the documents referred to in this Agreement)
a complete and  exclusive  statement of the terms of the  agreement  between the
parties with respect to its subject  matter.  This  Agreement may not be amended
except by a written  agreement  executed  by the  party to be  charged  with the
amendment.

                  13.9     Sellers' Disclosure Schedule.

     (a) The disclosures in the Sellers' Disclosure  Schedule,  and those in any
Supplement  thereto,  must relate only to the  representations and warranties in
the Section of the Agreement to which they expressly relate and not to any other
representation  or warranty in this  Agreement,  unless it is obvious,  from the
disclosure,  in light of the circumstances  under which such disclosure is made,
that other representations and warranties are affected thereby.

     (b) In the event of any inconsistency between the statements in the body of
this  Agreement  and those in the Sellers'  Disclosure  Schedule  (other than an
exception  expressly set forth as such in the Company  Disclosure  Schedule with
respect to a specifically identified representation or warranty), the statements
in the body of this Agreement will control.

     13.10 Assignments, Successors, and No Third Party Rights. Neither party may
assign any of its rights under this  Agreement  without the prior consent of the
other parties,  which will not be unreasonably  withheld,  except that Buyer may
assign any of its rights  under this  Agreement to any  Subsidiary  of Buyer but
Buyer will not be  relieved  of its  obligations  hereunder  as a result of such
assignment.  Subject to the preceding sentence, this Agreement will apply to, be
binding in all respects  upon,  and inure to the benefit of the  successors  and


                                       78
<PAGE>

permitted  assigns of the  parties.  Nothing  expressed  or  referred to in this
Agreement  will be  construed  to give any Person other than the parties to this
Agreement any legal or equitable right,  remedy,  or claim under or with respect
to this Agreement or any provision of this Agreement.  This Agreement and all of
its  provisions  and  conditions  are for the sole and exclusive  benefit of the
parties to this Agreement and their successors and assigns.

                  13.11 Severability. If any provision of this Agreement is held
invalid  or  unenforceable  by any court of  competent  jurisdiction,  the other
provisions of this Agreement will remain in full force and effect. Any provision
of this  Agreement  held  invalid or  unenforceable  only in part or degree will
remain in full force and effect to the extent not held invalid or unenforceable.

                  13.12 Section Headings, Construction. The headings of Sections
in this  Agreement  are  provided for  convenience  only and will not affect its
construction  or  interpretation.  All  references  to  "Sections"  refer to the
corresponding Sections of this Agreement.  All words used in this Agreement will
be construed to be of such gender or number as the circumstances require. Unless
otherwise expressly provided,  the word "including" does not limit the preceding
words or terms.

                  13.13  Interpretation  of Agreement.  This  Agreement has been
submitted to the scrutiny of all parties hereto and their respective counsel and
shall be given a fair and reasonable  interpretation without consideration being
given to its having been drafted by either party or its counsel.

                  13.14  Time of  Essence.  With  regard  to all  dates and time
periods set forth or referred to in this Agreement, time is of the essence.

     13.15 Governing Law. This Agreement will be governed by and construed under
the laws of the  State of  Pennsylvania  without  regard  to  conflicts  of laws
principles.

                  13.16  Counterparts.  This Agreement may be executed in one or
more  counterparts,  each of which will be deemed to be an original copy of this
Agreement and all of which,  when taken  together,  will be deemed to constitute
one and the same agreement.


         IN WITNESS WHEREOF,  the parties have executed this Agreement as of the
date first written above.


                                       79
<PAGE>





BUYER:                                          EMCON

ORGANIC WASTE TECHNOLOGIES, INC.,               EMCON, a California corporation
  a Delaware corporation


By: /s/R. Michael Momboisse                     By:   /s/R. Michael Momboisse
    ---------------------------------              --------------------------

Its:  Director                                 Its:  CFO & VP - Legal
     --------------------------------               -------------------------


SELLERS:                                     COMPANY

                                             NATIONAL EARTH PRODUCTS, INC, 
                                             a Pennsylvania corporation


    /s/Dennis M. Grimm                        By:   /s/Dennis M. Grimm 
-------------------------------------           ------------------------------
Dennis M. Grimm                                   Dennis M. Grimm


 /s/Charles H. Gearhart                     Its:   President
------------------------------------            ------------------------------
Charles H. Gearhart

                                       80