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                                                                   EXHIBIT 10.12


                         EXECUTIVE EMPLOYMENT AGREEMENT


         This EXECUTIVE EMPLOYMENT AGREEMENT is made and entered into effective
January 1, 1999, by and between ALLIED WASTE INDUSTRIES, INC., a Delaware
corporation having its principal executive office at 15880 North Greenway Hayden
Loop, Suite 100, Scottsdale, Arizona 85260 ("Company") and DONALD W. SLAGER
("Executive").

                              W I T N E S S E T H:

         WHEREAS, the Company desires to employ the Executive in an executive
capacity and the Executive desires to enter the Company's employ.

         NOW, THEREFORE, for and in consideration of the mutual promises,
covenants and obligations contained herein, and other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
Company and the Executive hereby agree as follows:

         CERTAIN DEFINITIONS. As used in this Agreement, the following terms
have the meanings prescribed below:

         Affiliate is used in this Agreement to define a relationship to a
person or entity and means a person or entity who, directly or indirectly
through one or more intermediaries, controls, is controlled by, or is under
common control with, such person or entity.

         Annual Bonus shall have the meaning assigned thereto in Section 4.2
hereof. Base Salary shall have the meaning, assigned thereto in Section 4.1
hereof.

         Beneficial Owner shall have the meaning assigned thereto in Rule
13(d)-3 under the Exchange Act; provided, however, and without limitation, that
any individual, corporation, partner ship, group, association or other person or
entity that has the right to acquire any Voting Stock at any time in the future,
whether such right is (a) contingent or absolute or (b) exercisable presently or
at any time in the future, pursuant to any agreement or understanding or upon
the exercise or conversion of rights, options or warrants, or otherwise, shall
be the Beneficial Owner of such Voting Stock.

         Cause shall have the meaning assigned thereto in Section 5.3 hereof.

         Change in Control of the Company shall be deemed to have occurred if
(i) the Company merges or consolidates, or agrees to merge or to consolidate,
with any other corporation (other than a wholly-owned direct or indirect
subsidiary of the Company) and is not the surviving corporation (or survives as
a subsidiary of another corporation), (ii) the Company sells, or agrees to sell,
all or substantially all of its assets to any other person or entity, (iii) the
Company is dissolved, (iv) any third person or entity (other than a trustee or
committee of any qualified employee benefit plan of the Company) together with
its Affiliates shall become or shall have publicly announced its intention to
become (by tender offer or otherwise), directly or indirectly, 
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the Beneficial Owner of at least 30% of the Voting Stock of the Company, or (v)
the individuals who constitute the Board of Directors of the Company as of the
Effective Date ("Incumbent Board") shall cease for any reason to constitute at
least a majority of the Board of Directors; provided, that any person becoming a
director whose election or nomination for election was approved by a majority of
the members of the Incumbent Board shall be considered, for the purposes of this
Agreement, a member of the Incumbent Board.

         Code means the Internal Revenue Code of 1986, as amended, and the rules
and regulations promulgated by the Internal Revenue Service thereunder, all as
in effect from time to time during the Employment Period.

         Common Stock means the Company's common stock, par value $.01 per
share.

         Company means Allied Waste Industries, Inc., a Delaware corporation,
the principal executive office of which is located at 15880 North Greenway
Hayden Loop, Suite 100, Scottsdale, Arizona 85260.

         Confidential Information shall have the meaning assigned thereto in
Section 8.2 hereof.

         Date of Termination means the earliest to occur of (i) the date of the
Executive's death, (ii) the date on which the Executive terminates this
Agreement for any reason other than Good Reason or (iii) the date of receipt of
the Notice of Termination, or such later date as may be prescribed in the Notice
of Termination in accordance with Section 5.6 hereof.

         Disability means an illness or other disability which prevents the
Executive from discharging his responsibilities under this Agreement for a
period of 180 consecutive calendar days, or an aggregate of 180 calendar days in
any calendar year, during the Employment Period, all as determined in good faith
by the Board of Directors of the Company (or a committee thereof).

         Effective Date means January 1, 1999.

         Employment Period shall have the meaning assigned thereto in Section 3
hereof.

         Exchange Act means the Securities Exchange Act of 1934, as amended, and
the rules and regulations promulgated by the Securities and Exchange Commission
thereunder, all as in effect from time to time during the Employment Period.

         Executive means Donald W. Slager.

         Good Reason shall have the meaning assigned thereto in Section 5.5
hereof.

         Notice of Termination shall have the meaning assigned thereto in
Section 5.6 hereof.

         Vacation Time shall have the meaning assigned thereto in Section 4.3
hereof.


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         Voting Stock means all outstanding shares of capital stock of the
Company entitled to vote generally in an election of directors; provided,
however, that if the Company has shares of Voting Stock entitled to more or less
than one vote per share, each reference to a proportion of the issued and
outstanding shares of Voting Stock shall be deemed to refer to the proportion of
the aggregate votes entitled to be cast by the issued and outstanding shares of
Voting Stock.

         Without Cause shall have the meaning assigned thereto in Section 5.4
hereof.

         GENERAL DUTIES OF COMPANY AND EXECUTIVE.

                  The Company agrees to employ the Executive, and the Executive
agrees to accept employment by the Company and to serve the Company as its Vice
President, Operations. The authority, duties and responsibilities of the
Executive shall include those described in Schedule A to this Agreement, and
such other or additional duties as may from time to time be assigned to the
Executive by the Board of Directors (or a committee thereof) and agreed to by
the Executive, which will be reflected in an amended Schedule A. While employed
hereunder, the Executive shall devote reasonable time and attention during
normal business hours to the affairs of the Company and use his best efforts to
perform faithfully and efficiently his duties and responsibilities. The
Executive may (i) serve on corporate, civic or charitable boards or committees,
(ii) deliver lectures, fulfill speaking engagements or teach at educational
institutions, and (iii) manage personal investments, so long as such activities
do not significantly interfere with the performance of the Executive's duties
and responsibilities.

                  The Executive agrees and acknowledges that he owes a fiduciary
duty of loyalty, fidelity and allegiance to act at all times in the best
interests of the Company and to do no act and to make no statement, oral or
written, which would injure Company's business, its interests or its reputation.

                  The Executive agrees to comply at all times during the
Employment Period with all applicable policies, rules and regulations of the
Company, including, without limitation, the Company's Code of Ethics and the
Company's policy regarding trading Common Stock, as each is in effect from time
to time during the Employment Period.

         TERM. Unless sooner terminated pursuant to Section 5 of this Agreement,
the Executive's Employment Period under this Agreement shall be a period of
three (3) years beginning on the Effective Date; provided that, beginning on the
first anniversary of the Effective Date, the Employment Period shall be for a
continuous period of two (2) years, such that on any given date thereafter, the
Executive's Employment Period shall always be two (2) years from the date in
question.


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         COMPENSATION AND BENEFITS.

                  Base Salary. As compensation for services to the Company, the
Company shall pay to the Executive until the Date of Termination an annual base
salary of $_______________ ("Base Salary"). The Board of Directors (or a
committee thereof), in its discretion, may increase the Base Salary based upon
relevant circumstances. The Base Salary shall be payable in equal semimonthly
installments or in accordance with the Company's established policy, subject
only to such payroll and withholding deductions as may be required by law and
other deductions applied generally to employees of the Company for insurance and
other employee benefit plans. For all purposes under this Agreement, the
Executive's Base Salary shall include any amount which is deferred under any
nonqualified plan or arrangement.

                  Bonus. In addition to the Base Salary, the Executive shall be
awarded, for each fiscal year until the Date of Termination, an annual bonus
(either pursuant to a bonus or incentive plan or program of the Company or
otherwise) in an amount to be determined by the Board of Directors (or a
committee thereof) in its sole discretion ("Annual Bonus"). Each such Annual
Bonus shall be payable at a time to be determined by the Board of Directors (or
a committee thereof) in its sole discretion. For all purposes under this
Agreement, the Executive's Annual Bonus shall include any amount which is
deferred under any nonqualified plan or arrangement.

                  Vacation. Until the Date of Termination, the Executive shall
be entitled to four weeks paid vacation during each one year period commencing
on the Effective Date ("Vacation Time"). Any Vacation Time not taken during the
applicable one year period will not accrue and will expire on the applicable
anniversary of the Effective Date.

                  Automobile Allowance. Until the Date of Termination, the
Executive shall receive an automobile allowance of $600.00 per month
("Automobile Allowance"). The Board of Directors (or a committee thereof), in
its discretion, may increase the Automobile Allowance based upon relevant
circumstances.

                  Club Membership Dues. Until the Date of Termination, the
Executive shall receive an amount per month equal to the monthly membership dues
which the Executive pays for one club or organization of Executive's choice.

                  Incentive, Savings, Retirement and Stock Plans. The Executive
shall participate in and be eligible to receive all benefits under all executive
incentive, savings, retirement and stock (including any stock option, restricted
stock, phantom stock and other stock rights) plans and programs currently
maintained or hereinafter established by the Company for the benefit of its
executive officers and/or employees (collectively "Compensation Plans"). The
Executive's participation in all such Plans shall be governed by the terms and
provisions of each such Plan.

                  Welfare Benefit Plans. The Executive and/or the Executive's
family, as the case may be, shall be eligible to participate in and shall
receive all benefits under each welfare benefit plan of the Company currently
maintained or hereinafter established by the Company for the benefit of its
employees. Such welfare benefit plans may include, without limitation, medical,


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dental, disability, group life, accidental death and travel accident insurance
plans and programs (collectively "Welfare Plans"). The Executive's and/or the
Executive's family's participation in the Welfare Plans shall be subject to the
terms and conditions of each Welfare Plan.

                  Reimbursement of Expenses. The Executive may from time to time
until the Date of Termination incur various business expenses customarily
incurred by persons holding positions of like responsibility, including, without
limitation, travel, entertainment and similar expenses incurred for the benefit
of the Company. Subject to the Company's policy regarding the reimbursement of
such expenses as in effect from time to time during the Employment Period, which
does not necessarily allow reimbursement of all such expenses, the Company shall
reimburse the Executive for such expenses from time to time, at the Executive's
request, and the Executive shall account to the Company for all such expenses.

         TERMINATION.

                  Death. This Agreement shall terminate automatically upon the
death of the Executive.

                  Disability. The Company may terminate this Agreement, upon
written notice to the Executive delivered in accordance with Sections 5.6 and
12.1 hereof, upon the Disability of the Executive.

                  Cause. The Company may terminate this Agreement, upon
written notice to the Executive delivered in accordance with Sections 5.6 and
12.1 hereof, for Cause. For purposes of this Agreement, "Cause" means (i) the
conviction of the Executive for a felony, (ii) the Executive's willful refusal,
without proper legal cause, to perform his duties and responsibilities as
contemplated in this Agreement or (iii) the Executive's willfully engaging in
activities which would (A) constitute a breach of any term of this Agreement,
the Company's Code of Ethics, the Company's policies regarding trading Common
Stock or reimbursement of business expenses or any other applicable policies,
rules or regulations of the Company, or (B) result in a material injury to the
business, condition (financial or otherwise), results of operations or prospects
of the Company or its Affiliates (as determined in good faith by the Board of
Directors of the Company or a committee thereof). For purposes of the definition
of "Cause," no act or failure to act shall be considered "wilful" unless it is
done, or omitted to be done, in bad faith without reasonable belief that the
action or omission was in the best interests of the Company.

                  Without Cause. The Company may terminate this Agreement
Without Cause, upon written notice to the Executive delivered in accordance with
Sections 5.6 and 12.1 hereof. For purposes of this Agreement, the Executive will
be deemed to have been terminated "Without Cause" if the Executive is terminated
by the Company for any reason other than Cause, Disability or Death.

                  Good Reason. The Executive may terminate this Agreement
for Good Reason, upon written notice to the Company delivered in accordance with
Sections 5.6 and 12.1 hereof. For purposes of this Agreement, "Good Reason"
means (i) the assignment to the Executive of any duties inconsistent in any
respect with the Executive's duties or responsibilities as 


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contemplated in this Agreement, (ii) any other action by the Company which
results in a diminishment in the Executive's position (including status,
offices, titles and reporting requirements), authority, duties or
responsibilities, (iii) any breach by the Company of any of the provisions of
this Agreement, (iv) requiring the Executive to relocate permanently to any
office or location other than the Phoenix-Scottsdale metropolitan area, without
his consent, or (v) any reduction, or attempted reduction, at any time during
the Employment Period, of the Base Salary of the Executive.

                  Notice of Termination. Any termination of this Agreement
by the Company for Cause, Without Cause or as a result of the Executive's
Disability, or by the Executive for Good Reason, shall be communicated by Notice
of Termination to the other party hereto given in accordance with this
Agreement. For purposes of this Agreement, a "Notice of Termination" means a
written notice which (i) indicates the specific termination provision in this
Agreement relied upon, (ii) sets forth in reasonable detail the facts and
circumstances claimed to provide a basis for termination of the Executive's
employment under the provision so indicated and (iii) specifies the termination
date, if such date is other than the date of receipt of such notice (which
termination date shall not be more than 15 days after the giving of such
notice).

         OBLIGATIONS OF COMPANY UPON TERMINATION.

                  Cause, Other than Good Reason. If this Agreement is terminated
either by the Company for Cause or by the Executive for any reason other than
Good Reason, the Company shall pay to the Executive, in a lump sum cash payment
within 30 days after the Date of Termination, the aggregate of the Executive's
Base Salary (as in effect on the Date of Termination) owing as of the Date of
Termination, if not theretofore paid, and, in the case of compensation
previously deferred by the Executive, all amounts of such compensation
previously deferred and not yet paid by the Company (unless such payment is
inconsistent with the terms of any payment election made by the Executive with
respect to such deferred compensation). The Company also shall, promptly upon
submission by the Executive of supporting documentation, pay or reimburse to the
Executive any costs and expenses (including moving and relocation expenses) paid
or incurred by the Executive which would have been payable under Section 4.8 of
this Agreement if the Executive's employment had not terminated.

         All other obligations of the Company and rights of the Executive
hereunder shall terminate effective as of the Date of Termination; provided,
however, that the Executive's rights under any Compensation Plan shall be
governed by the terms and provisions of each such Plan and are not necessarily
severed on the Date of Termination.

         Death or Disability.

                      Subject to the provisions of this Section 6.2, if this
Agreement is terminated as a result of the Executive's death or Disability, the
Company shall pay to the Executive or his estate, in a lump sum cash payment
within 30 days of the Date of Termination, the greater of (i) that portion of
the Executive's Base Salary (as in effect on the Date of Termination) owing in
respect of the balance of the Employment Period pursuant to Section 3 hereof or
(ii) the Executive's Base Salary (as in effect on the Date of Termination). The


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Company may purchase insurance to cover all or any part of the obligation
contemplated in the foregoing sentence, and the Executive agrees to submit to a
physical examination to facilitate the procurement of such insurance. The
Company also shall, promptly upon submission by the Executive of supporting
documentation, pay or reimburse to the Executive any costs and expenses
(including moving and relocation expenses) paid or incurred by the Executive
which would have been payable under Section 4.8 of this Agreement if the
Executive's employment had not terminated. Until the Executive obtains other
health coverage through another employer's health plan or, if longer, for a
period of five (5) years, the Company shall continue providing health coverage
to the Executive and/or the Executive's family at least equal to that which
would have been provided to them under Section 4.7 if the Executive's employment
had not terminated; provided that any such coverage shall cease immediately if
the Executive violates any of the applicable provisions of Article 11.

                      Whenever compensation is payable to the Executive
hereunder during a period in which he is partially or totally disabled, and such
Disability would (except for the provisions hereof) entitle the Executive to
Disability income or salary continuation payments from the Company according to
the terms of any plan or program presently maintained or hereafter established
by the Company, the Disability income or salary continuation paid to the
Executive pursuant to any such plan or program shall be considered a portion of
the payment to be made to the Executive pursuant to this Section 6.2 and shall
not be in addition hereto. If Disability income is payable directly to the
Executive by an insurance company under the terms of an insurance policy paid
for by the Company, the amounts paid to the Executive by such insurance company
shall be considered a portion of the payment to be made to the Executive
pursuant to this Section 6.2 and shall not be in addition hereto.

         Good Reason; Without Cause. If this Agreement is terminated either by
the Executive for Good Reason or by the Company Without Cause:

                      the Company shall pay to the Executive, in a lump sum cash
payment within 30 days after the Date of Termination, the aggregate of the
following amounts:

                           if not theretofore paid, the Executive's Base Salary
         (as in effect on the Date of Termination) through the Date of
         Termination;

                           an amount equal to the largest Annual Bonus paid to
         the Executive out of the last three (3) fiscal years preceding the Date
         of Termination; and

                           in the case of compensation previously deferred by
         the Executive, all amounts of such compensation previously deferred and
         not yet paid by the Company (unless such payment is inconsistent with
         the terms of any payment election made by the Executive with respect to
         such deferred compensation).

                      the Company shall, promptly upon submission by the
Executive of supporting documentation, pay or reimburse to the Executive any
costs and expenses (including moving and relocation expenses) paid or incurred
by the Executive which would have been 


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payable under Section 4.8 of this Agreement if the Executive's employment had
not terminated; and

                      until the Executive obtains other health coverage through
another employer's health plan or, if longer, for a period of five (5) years,
the Company shall continue providing health coverage to the Executive and/or the
Executive's family at least equal to that which would have been provided to them
under Section 4.7 if the Executive's employment had not terminated; provided
that any such coverage shall cease immediately if the Executive violates any of
the applicable provisions of Article 11.

                      the Company shall pay to the Executive, in equal
semi-monthly installments, the greater of (i) that portion of the Executive's
Base Salary (as in effect on the Date of Termination) owing, in respect of the
balance of the Employment Period pursuant to Section 3 hereof or (ii) the
Executive's Base Salary (as in effect on the Date of Termination); provided that
such payments shall cease immediately if the Executive violates any applicable
provision of Article 11.

         Change in Control. If (a) this Agreement is terminated either by the
Executive for Good Reason or by the Company Without Cause and (b) a Change in
Control of the Company has occurred within the two-year period preceding, or
within the one-year period following, the Date of Termination, then, in addition
to the obligations of the Company set forth in Section 6.3 hereof, the Company
shall pay to the Executive, in a lump sum cash payment within 30 days after the
Date of Termination, two times the sum of (x) the Executive's Base Salary (as in
effect on the Date of Termination or such higher rate as may have been in effect
at any time during the 90-day period preceding the Date of Termination) and (y)
the Annual Bonus paid to the Executive for the last full fiscal year. The rights
given to the Executive herein do not apply to the Change of Control of the
Company which occurred when Apollo Advisors, L.P. and The Blackstone Group
acquired the Common Stock of Laidlaw Transportation, Inc.

         EXECUTIVE'S OBLIGATION TO AVOID CONFLICTS OF INTEREST.

         In keeping with the Executive's fiduciary duties to the Company, the
Executive agrees that he shall not knowingly become involved in a conflict of
interest with the Company, or upon discovery thereof, allow such a conflict to
continue. The Executive further agrees to disclose to the Company, promptly
after discovery, any facts or circumstances which might involve a conflict of
interest with the Company.

         The Company and the Executive recognize that it is impossible to
provide an exhaustive list of actions or interests which constitute a "conflict
of interest." Moreover, the Company and the Executive recognize that there are
many borderline situations. In some instances, full disclosure of facts by the
Executive to the Company is all that is necessary to enable the Company to
protect its interests. In others, if no improper motivation appears to exist and
the Company's interests have not suffered, prompt elimination of the outside
interest will suffice. In still others, it may be necessary for the Company to
terminate the employment relationship. The Company and the Executive agree that
the Company's determination as to whether or not a conflict of interest exists
shall be conclusive. The Company reserves the right to take such action as, in
its judgment, will end the conflict of interest.


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         In this connection, it is agreed that any direct or indirect interest
in, connection with or benefit from any outside activities, particularly
commercial activities, which interest might in any way adversely affect the
Company or its Affiliates, involves a possible conflict of interest.
Circumstances in which a conflict of interest on the part of the Executive would
or might arise, and which should be reported immediately to the Company,
include, but are not limited to, the following:

                      Ownership of a material interest in any lender, supplier,
contractor, subcontractor, customer or other entity with which the Company does
business.

                      Acting in any capacity, including director, officer,
partner, consultant, employee, distributor, agent or the like, for any lender,
supplier, contractor, subcontractor, customer or other entity with which the
Company does business.

                      Acceptance, directly or indirectly, of payments, services
or loans from a lender, supplier, contractor, subcontractor, customer or other
entity with which the Company does business, including, without limitation,
gifts, trips, entertainment or other favors of more than a nominal value, but
excluding loans from publicly held insurance companies and commercial or savings
banks at market rates of interest.

                      Use of information or facilities to which the Executive
has access in a manner which will be detrimental to the Company's interests,
such as use for the Executive's own benefit of know-how or information developed
through the Company's business activities.

                      Disclosure or other misuse of information of any kind
obtained through the Executive's connection with the Company.

                      Acquiring or trading in, directly or indirectly, other
properties or interests connected with the design or marketing of products or
services designed or marketed by the Company.

         EXECUTIVE'S CONFIDENTIALITY OBLIGATION.

         The Executive hereby acknowledges, understands and agrees that all
Confidential Information is the exclusive and confidential property of the
Company and its Affiliates which shall at all times be regarded, treated and
protected as such in accordance with this Section 8. The Executive acknowledges
that all such Confidential Information is in the nature of a trade secret.

         For purposes of this Agreement, "Confidential Information" means
information, that is used in the business of the Company or its Affiliates and
(i) is proprietary to, about or created by the Company or its Affiliates, (ii)
gives the Company or its Affiliates some competitive business advantage or the
opportunity of obtaining such advantage or the disclosure of which could be
detrimental to the interests of the Company or its Affiliates, (iii) is
designated as Confidential Information by the Company or its Affiliates, is
known by the Executive to be 


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considered confidential by the Company or its Affiliates, or from all the
relevant circumstances should reasonably be assumed by the Executive to be
confidential and propriety to the Company or its Affiliates, or (iv) is not
generally known by non-Company personnel. Such Confidential Information
includes, without limitation, the following types of information and other
information of a similar nature (whether or not reduced to writing or designed
as confidential):

                      Internal personnel and financial information of the
Company or its Affiliates, vendor information (including vendor characteristics,
services, prices, lists and agreements), purchasing and internal cost
information, internal service and operational manuals, and the manner and
methods of conducting the business of the Company or its Affiliates;

                      Marketing and development plans, price and cost data,
price and fee amounts, pricing and billing policies, quoting procedures,
marketing techniques, forecasts and forecast assumptions and volumes, and future
plans and potential strategies (including, without limitation, all information
relating to any acquisition prospect and the identity of any key contact within
the organization of any acquisition prospect) of the Company or its Affiliates
which have been or are being discussed;

                      Names of customers and their representatives, contracts
(including their contents and parties), customer services, and the type,
quantity, specifications and content of products and services purchased, leased,
licensed or received by customers of the Company or its Affiliates; and

                      Confidential and proprietary information provided to the
Company or its Affiliates by any actual or potential customer, government agency
or other third party (including businesses, consultants and other entities and
individuals).

         As a consequence of the Executive's acquisition or anticipated
acquisition of Confidential Information, the Executive shall occupy a position
of trust and confidence with respect to the affairs and business of the Company
and its Affiliates. In view of the foregoing, and of the consideration to be
provided to the Executive, the Executive agrees that it is reasonable and 
necessary that the Executive make each of the following covenants:

                      At any time during the Employment Period and thereafter,
the Executive shall not disclose Confidential Information to any person or
entity, either inside or outside of the Company, other than as necessary in
carrying out his duties and responsibilities as set forth in Section 2 hereof,
without first obtaining the Company's prior written consent (unless such
disclosure is compelled pursuant to court orders or subpoena, and at which time
the Executive shall give notice of such proceedings to the Company).

                      At any time during the Employment Period and thereafter,
the Executive shall not use, copy or transfer Confidential Information other
than as necessary in carrying out his duties and responsibilities as set forth
in Section 2 hereof, without first obtaining the Company's prior written
consent.


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                      On the Date of Termination, the Executive shall promptly
deliver to the Company (or its designee) all written materials, records and
documents made by the Executive or which came into his possession prior to or
during the Employment Period concerning, the business or affairs of the Company
or its Affiliates, including, without limitation, all materials containing
Confidential Information.

         DISCLOSURE OF INFORMATION, IDEAS, CONCEPTS, IMPROVEMENTS, DISCOVERIES
AND INVENTIONS. Consistent with the Executive's fiduciary duties to the Company,
the Executive agrees that during his employment by the Company, the Executive
shall promptly disclose in writing to the Company all information, ideas,
concepts, improvements, discoveries and inventions, which are conceived,
developed, made or acquired by the Executive, either individually or jointly
with others, and which relate to the business, products or services of the
Company or its Affiliates, irrespective of whether the Executive used the
Company's time or facilities and irrespective of whether such information, idea,
concept, improvement, discovery or invention was conceived, developed,
discovered or acquired by the Executive on the job, at home, or elsewhere. This
obligation extends to all types of information, ideas and concepts, including,
information, ideas and concepts relating to new types of services, corporate
opportunities, acquisition prospects, the identity of key representatives within
acquisition prospect organizations, prospective names or service marks for the
Company's business activities, and the like.

         OWNERSHIP OF INFORMATION, IDEAS, CONCEPTS, IMPROVEMENTS, DISCOVERIES
AND ALL ORIGINAL WORKS OF AUTHORSHIP.

         All information, ideas, concepts, improvements, and discoveries which
are conceived, made, developed or acquired by the Executive or which are
disclosed or made known to the Executive, individually or in conjunction with
others, during the Executive's employment by the Company and which relate to the
business, products or services of the Company or its Affiliates (including,
without limitation, all such information relating to corporate opportunities,
research, financial and sales data, pricing and trading terms, evaluations,
opinions, interpretations, acquisition prospects, the identity of customers or
their requirements, the identity of key contacts within the customers'
organizations or within the organization of acquisition prospects, marketing and
merchandising techniques, and prospective names and service marks) are and shall
be the sole and exclusive property of the Company. Furthermore, all drawings,
memoranda, notes, records, files, correspondence, manuals, models,
specifications, computer programs, maps and all other writings or materials of
any type embodying any of such information, ideas, concepts, improvements, and
discoveries are and shall be the sole and exclusive property of the Company.

         In particular, the Executive hereby specifically sells, assigns,
transfers and conveys to the Company all of his worldwide right, title and
interest in and to all such information, ideas, concepts, improvements, and
discoveries, and any United States or foreign applications therefor. The
Executive shall assist the Company and its nominee at all times and in all
manners, during the Employment Period and thereafter, in the protection of such
information, ideas, concepts, improvements, or discoveries.


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         In the event the Executive creates, during the Employment Period, any
original work of authorship fixed in any tangible medium of expression which is
the subject matter of copyright such as videotapes, written presentations on
acquisitions, computer programs, drawings, maps, architectural renditions,
models, manuals, brochures or the like relating to the Company's business
products or services, whether such work is created solely by the Executive or
jointly with others, the Company shall be deemed the author of such work if the
work is prepared by the Executive within the scope of his employment; or, if the
work is not prepared by the Executive within the scope of his employment but is
specially ordered by the Company as a contribution to a collective work, as a
part of a motion picture or other audiovisual work, as a translation, as a
supplementary work, as a compilation or as an instructional text, then the work
shall be considered to be a work made for hire, and the Company shall be the
author of such work. If such work is neither prepared by the Executive within
the scope of his employment nor a work specially ordered and deemed to be a work
made for hire, then the Executive hereby agrees to sell, transfer, assign and
convey, and by these presents, does sell, transfer, assign and convey, to the
Company all of the Executive's worldwide right, title and interest in and to
such work and all rights of copyright therein. The Executive agrees to assist
the Company and its Affiliates, at all times, during the Employment Period and
thereafter, in the protection of the Company's worldwide right, title and
interest in and to such work and all rights of copyright therein, which
assistance shall include, but shall not be limited to, the execution of all
documents requested by the Company or its nominee and the execution of all
lawful oaths and applications for registration of copyright in the United States
and foreign countries.

         EXECUTIVE'S NON-COMPETITION AND NON-SOLICITATION OBLIGATIONS.

         Until the Date of Termination, the Executive shall not, acting alone or
in conjunction with others, directly or indirectly, engage, participate, invest,
accept employment or render services as a principal, director, officer, agent,
employee, employer, consultant or in any other individual or representative
capacity in or with any business which competes, directly or indirectly, with
the Employer's business in any of the business territories in which the Company
or any of its Affiliates is presently or from time to time during the Employment
Period conducting business, or take any action inconsistent with the fiduciary
relationship of an employee to his employer; provided, however, that the
beneficial ownership by the Executive of up to three (3) percent of the Voting
Stock of any corporation subject to the periodic reporting requirements of the
Exchange Act shall not violate this Section 11.1(a).

                      In addition to the other obligations agreed to by the
Executive in this Agreement, the Executive agrees that until the Date of
Termination, he shall not, directly or indirectly, (i) induce, entice or solicit
any employee of the Company to leave his employment, (ii) contact, communicate
or solicit any customer or acquisition prospect of the Company derived from any
customer list, customer lead, mail, printed matter or other information secured
from the Company or its present or past employees (other than in connection with
the performance of his services for the Company in accordance with Section 2 of
this Agreement) or (iii) in any other manner use any customer lists or customer
leads, mail, telephone numbers, printed material or other information of the
Company relating thereto (other than in connection with the performance of his
services for the Company in accordance with Section 2 of this Agreement).


                                       12
<PAGE>   13

         If this Agreement is terminated either by the Company for Cause or by
the Executive for any reason other than Good Reason, then for a period of three
(3) years following the Date of Termination, the Executive shall not, acting
alone or in conjunction with others, directly or indirectly, engage,
participate, invest, accept employment, or render services as a principal,
director, officer, agent, employee, employer, consultant or in any other
individual or representative capacity in or with any business which competes,
directly or indirectly, with the Employer's business and which is located in any
of the business territories in which the Company or any of its Affiliates is
presently or at the Date of Termination conducting business, or take any action
inconsistent with the fiduciary relationship of an employee to his employer;
provided, however, that the beneficial ownership by the Executive of up to three
(3) percent of the Voting Stock of any corporation subject to the periodic
reporting requirements of the Exchange Act shall not violate this Section
11.2(a).

                      In addition to the other obligations agreed to by the
Executive in this Agreement, the Executive agrees that if this Agreement is
terminated either by the Company for Cause or by the Executive for any reason
other than Good Reason, then for a period of three (3) years following the Date
of Termination, he shall not, directly or indirectly, (i) induce, entice or
solicit any employee of the Company to leave his employment, (ii) contact,
communicate or solicit any customer or acquisition prospect of the Company
derived from any customer list, customer lead, mail, printed matter or other
information secured from the Company or its present or past employees or (iii)
in any other manner use any customer lists or customer leads, mail, telephone
numbers, printed material or other information of the Company relating thereto.

         If this Agreement is terminated either by the Executive for Good Reason
or by the Company Without Cause, provided that no Change in Control of the
Company has occurred during the two-year period preceding or within the one-year
period following the Date of Termination then, for a period of one (1) year
following the Date of Termination, the Executive shall not, acting alone or in
conjunction with others, directly or indirectly, engage, participate, invest,
accept employment, or render services as a principal, director, officer, agent,
employee, employer, consultant, or in any other individual or representative
capacity in or with any business which competes, directly or indirectly, with
the Employer's business and which is located in any of the business territories
in which the Company or any of its Affiliates is presently or at the Date of
Termination conducting business, or take any action inconsistent with the
fiduciary relationship of an employee to his employer; provided, however, that
the beneficial ownership by the Executive of up to three (3) percent of the
Voting Stock of any corporation subject to the periodic reporting requirements
of the Exchange Act shall not violate this Section 11.3(a).

                      In addition to the other obligations agreed to by the
Executive in this Agreement, the Executive agrees that if this Agreement is
terminated either by the Executive for Good Reason or by the Company Without
Cause, provided that no Change in Control of the Company has occurred during the
two-year period preceding or within the one-year period following the Date of
Termination, then for a period of one (1) year following the Date of
Termination, he shall not, directly or indirectly, (i) induce, entice or solicit
any employee of the Company to leave his employment, (ii) contact, communicate
or solicit any customer or acquisition prospect of the Company derived from any
customer list, customer lead, mail, printed matter 


                                       13
<PAGE>   14

or other information secured from the Company or its present or past employees
or (iii) in any other manner use any customer lists or customer leads, mail,
telephone numbers, printed material or other information of the Company relating
thereto.

         If this Agreement is terminated (a) either by the Executive for Good
Reason or by the Company Without Cause and (b) a Change in Control of the
Company has occurred during the two-year period preceding, or the one-year
period following, the Date of Termination, or if this Agreement is terminated,
as a result of the Executive's Disability, then the Executive shall not be
subject to any obligations under this Section 11.

         MISCELLANEOUS.

         Notices. All notices and other communications required or permitted
here under or necessary or convenient in connection herewith shall be in writing
and shall be deemed to have been given when delivered by hand or mailed by
registered or certified mail, return receipt requested, as follows (provided
that notice of a change of address shall be deemed given only when received):

If to the Company:

                  Allied Waste Industries, Inc.
                  15880 North Greenway Hayden Loop, Suite 100
                  Scottsdale, Arizona 85260

If to the Executive:

                  Donald W. Slager
                  9530 East Cortez
                  Scottsdale, Arizona 85260

or to such other names or addresses as the Company or the Executive, as the case
may be, shall designate by notice to the other party hereto in the manner
specified in this Section 12.1.

         Waiver of Breach. The waiver by any party hereto of a breach of any
provision of this Agreement shall neither operate nor be construed as a waiver
of any subsequent breach by any party.

         Assignment. This Agreement shall be binding upon and inure to the
benefit of the Company, its successors, legal representatives and assigns, and
upon the Executive, his heirs, executors, administrators, representatives and
assigns; provided, however, the Executive agrees that his rights and obligations
hereunder are personal to him and may not be assigned without the express
written consent of the Company.

         Entire Agreement, No Oral Amendments. This Agreement, together with any
schedule or exhibit attached hereto and any document, policy, rule or regulation
referred to herein, replaces and merges all previous agreements and discussions
relating to the same or 


                                       14
<PAGE>   15

similar subject matter between the Executive and the Company and constitutes the
entire agreement between the Executive and the Company with respect to the
subject matter of this Agreement. This Agreement may not be modified in any
respect by any verbal statement, representation or agreement made by any
employee, officer, or representative of the Company or by any written agreement
unless signed by an officer of the Company who is expressly authorized by the
Company to execute such document.

         Enforceability. If any provision of this Agreement or application
thereof to anyone or under any circumstances shall be determined to be invalid
or unenforceable, such invalidity or unenforceability shall not affect any other
provisions or applications of this Agreement which can be given effect without
the invalid or unenforceable provision or application.

         Jurisdiction, Venue. The laws of the State of Arizona shall govern the
interpretation, validity and effect of this Agreement without regard to the
place of execution or the place for performance thereof, and the Company and the
Executive agree that the courts situated in Maricopa County, Arizona shall have
personal jurisdiction over the Company and the Executive to hear all disputes
arising under this Agreement. This Agreement is to be at least partially
performed in Maricopa County, Arizona, and as such, the Company and the
Executive agree that venue shall be proper with the courts in Maricopa County,
Arizona to hear such disputes. In the event either the Company or the Executive
is not able to effect service of process upon the other party hereto with
respect to such disputes, the Company and the Executive expressly agree that the
Secretary of State for the State of Arizona shall be an agent of the Company
and/or the Executive to receive service of process on behalf of the Company
and/or the Executive with respect to such disputes.

         Injunctive Relief. The Company and the Executive agree that a breach of
any term of this Agreement by the Executive would cause irreparable damage to
the Company and that, in the event of such breach, the Company shall have, in
addition to any and all remedies of law, the right to any injunction, specific
performance and other equitable relief to prevent or to redress the violation of
the Executive's duties or responsibilities hereunder.


                                       15
<PAGE>   16

                  IN WITNESS WHEREOF, the undersigned, intending to be early
bound, have executed this Agreement as of the date first written above.


                                       ALLIED WASTE INDUSTRIES, INC.


                                       By _____________________________________
                                       Its ____________________________________

                                                                      "Company"



                                        _______________________________________
                                        Donald W. Slager
                                                                    "Executive"


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<PAGE>   17

                                  SCHEDULE "A"


                                       17