Exhibit 10.1

RESIGNATION AGREEMENT

This Resignation Agreement (“Resignation Agreement”) is entered into as of July
5, 2012 by and between Waste Management, Inc. (the “Company”) and Steven C.
Preston (“Preston”).

This Resignation Agreement is binding upon, and extends to, the parties and
their past and present officers, directors, employees, shareholders, parent
corporations, subsidiaries, affiliates, partners, agents, representatives,
heirs, executors, assigns, administrators, successors, predecessors, family
members, d/b/a’s, assumed names, and insurers, whether specifically mentioned
hereafter or not. A reference to a party in this Resignation Agreement
necessarily includes those persons and/or entities described in the foregoing
sentence.

WITNESSETH:

WHEREAS, Preston and the Company previously entered into an Employment
Agreement (the “Employment Agreement”);

WHEREAS, Preston has been employed by and has served as the Company’s Executive
Vice President—Finance, Recycling and Energy Services since October 1, 2011;

WHEREAS, Preston has notified the Company of his desire to voluntarily resign
from the Company without “Good Reason” as such term is defined in Section 5(d)
and governed by Section 6(d) of the Employment Agreement; and

WHEREAS, the parties now jointly desire to amend and supplement the employment
relationship and the Employment Agreement on the terms and conditions
hereinafter set forth.

NOW, THEREFORE, in consideration of the premises and agreements contained
herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree as
follows:

1. Resignation of Officer Positions; Termination of Employment. Effective as of
August 1, 2012 (or, if later, the date on which the Company shall file its
Quarterly Report on Form 10Q for the quarter ended June 30, 20120), Preston
shall cease to be the Company’s Executive Vice President—Finance, Recycling and
Energy Services. Thereafter, Preston’s employment with the Company shall
continue until such employment terminates pursuant to the terms of this
Resignation Agreement (the “Continued Employment Period”). Preston’s voluntary
resignation from the Company without Good Reason (as defined in the Employment
Agreement) shall be effective, and his employment relationship with the Company
shall terminate, no later than October 15, 2012, unless his employment shall be
earlier terminated by either party upon 30 days written notice.

2. Continued Employment Period. During the Continued Employment
Period, Preston shall perform such duties and have such responsibilities as may
be assigned to him from time to time by the Company’s President and Chief
Executive Officer (including, but not limited to, transition

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and assisting and counseling his successor Chief Financial Officer). During the
Continued Employment Period, the Company shall continue to
pay Preston his current base salary in accordance with the Company’s standard
payroll practices. Preston will not be eligible for any bonus for calendar year
2012. Preston has previously received certain equity awards, including a grant
on or about October 4, 2011 and another grant on or about March 9, 2012 that
vest over time. Preston acknowledges that, as a result of his voluntary
resignation, he will forfeit all equity awards that are not vested when Preston
ceases to be an employee of the Company.

Nothing in this Resignation Agreement (including, the terms of Paragraphs 1 and
2) shall in any way be interpreted or construed as a “Good Reason” event as
defined in Section 5(d) of the Employment Agreement or otherwise require the
Company to pay to Preston the post-employment severance amounts set forth in
Section 6(e) of the Employment Agreement.

3. Settlement and Acquisition of Goodwill. Preston waives and releases any and
all claims that the restrictive covenants contained in Paragraph 10 of the
Employment Agreement (the “Employment Agreement Restrictive Covenants”) are not
enforceable or are against public policy. Preston covenants not to file a
lawsuit or arbitration proceeding, pursue declaratory relief, or otherwise take
any legal action to challenge the enforceability of the Employment Agreement
Restrictive Covenants. The parties agree that the promise of continued
employment and the compensation and benefits associated with same referred to in
Paragraph 2 above are, in part, consideration for the settlement of all disputes
regarding the enforceability and application of Employment Agreement Restrictive
Covenants, and are payment for exclusive right to the business goodwill, trade
secrets, and confidential information developed by Preston in the course of his
employment with the Company. To help preserve the value of the goodwill, trade
secrets, and confidential information acquired herewith, it is agreed
that Preston will comply with the Employment Agreement Restrictive Covenants
(incorporated herein by reference) for the periods of time set forth therein. It
is specifically agreed that the two-year Restricted Term set forth in Paragraph
10 of the Employment Agreement and the restrictions provided for therein shall
commence upon Preston’s termination of employment with the Company. In the event
that the Company, in its sole discretion, determines that Preston has engaged in
activities that violate the Employment Agreement Restrictive Covenants, the
Company shall have the right to discontinue and terminate Preston’
employment. Such termination of employment shall be in addition to and shall not
limit injunctive relief and/or any and all other rights and remedies that the
Company may have against Preston under the Employment Agreement or this
Resignation Agreement.

4. Assistance and Cooperation. Preston agrees that he will cooperate fully with
the Company and its counsel, upon their request, with respect to any proceeding
(including any litigation, arbitration, regulatory proceeding, investigation or
governmental action) that relates to matters with which Preston was involved
while he was an employee of the Company or of which he has knowledge.
Preston agrees to render such cooperation in a timely fashion and to provide
Company personnel and the Company’s counsel with the full benefit of his
knowledge with respect to any such matter. The Company shall
reimburse Preston for actual and reasonable costs and expenses, including
reasonable attorneys fees, related to his assistance in such matters.

 

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5. Choice of Laws. This Resignation Agreement is made and entered into in the
State of Texas, and shall in all respects be interpreted, enforced and governed
under the laws of the State of Texas. The language of all parts of this
Resignation Agreement shall in all cases be construed as a whole, according to
its fair meaning, and not strictly for or against either of the parties.

6. Severability. Should any provision of this Resignation Agreement be declared
or be determined by any court to be illegal or invalid, the validity of the
remaining parts, terms or provisions shall not be affected thereby and said
illegal or invalid part, term, or provision shall be deemed not to be a part of
this Resignation Agreement.

7. Complete Agreement. The parties agree that the Employment Agreement
(including any other amendments thereto) as modified by this Resignation
Agreement, contains the full and final expression of their agreements with
respect to the matters contained therein, and acknowledge that no other promises
have been made to or by any of the parties that are not set forth in these
Agreements.

The parties agree that neither the offer of, nor the execution of, this
Resignation Agreement will be construed as an admission of wrongdoing by anyone.
Instead, this Resignation Agreement is to be construed solely as a reflection of
the parties’ desire to facilitate a peaceful separation of employment and to
make sure there are no unresolved issues between them.

IN WITNESS WHEREOF, this Resignation Agreement is EXECUTED and EFFECTIVE as of
the day set forth above.

 

STEVEN C. PRESTON (“Preston”)     WASTE MANAGEMENT, INC.

/s/ Steven C. Preston

   

/s/ David P. Steiner

Steven C. Preston     By:   David P. Steiner       Chief Executive Officer

 

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