EXHIBIT 10.6



                PERFORMANCE STOCK APPRECIATION RIGHTS AGREEMENT


     AGREEMENT dated as of July 13, 1997, between Waste Management, Inc., a
Delaware Corporation (the "Company"), and Ronald T. LeMay (the "Executive").

     As an inducement to, and in consideration of, the Executive's agreement to
serve as the Chairman, President and Chief Executive Officer of the Company and
in order to keep the Executive whole in respect of certain option rights he is
forfeiting at Sprint Corporation ("Sprint"), the Company is providing the
Executive with the Performance Stock Appreciation Right ("Performance SAR") on
the terms hereinafter set forth and the Stock Appreciation Right on the terms
set forth in Exhibit E-1 to the Employment Agreement dated as of July 13, 1997
between the Company and the Executive (the "Employment Agreement") to compensate
the Executive for such forfeiture. This Agreement is entered into
contemporaneously with the execution and delivery of the Employment Agreement.

     1.   Grant of Units. The Company hereby grants to the Executive 500,000
Performance SAR Units ("Units") representing 500,000 shares of Sprint Common
Stock.

     2.   Base Value of a Unit. Each Unit shall have a base value of $47.9375
subject to adjustment as hereinafter provided (the "Base Value").

     3. Economic Entitlement of a Unit ("Spread"). During the period in which
the Performance SAR is exercisable as hereinafter provided, a Unit shall entitle
the Executive to an amount equal


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to the "Spread" in the Unit on the date he chooses to exercise the Performance
SAR in respect of that Unit. (He may, at any point during its period of
exercisability, exercise the Performance SAR in respect of some or all of his
Units but at any given date he may exercise the Performance SAR as to no fewer
than 50,000 Units or, if less, the balance of the Units.) For this purpose
"Spread" shall mean an amount equal to the current market price per share of
Sprint Common Stock on the date the Executive exercises the Performance SAR less
the Base Value of a Unit (as adjusted pursuant to Section 7 below). The "current
market price" per share of Sprint Common Stock at any date shall be deemed to be
the closing price on the date on which the Executive exercises the Performance
SAR, or if the markets are closed on such date, the next preceding day on which
the markets are open and Sprint Common Stock is traded. "Closing price" for any
date shall be, if the Sprint Common Stock is then listed or admitted to trading
on the New York Stock Exchange, Inc. or other national securities exchange, the
last reported sale price for the Sprint Common Stock as reported in the
consolidated transaction or other reporting system for securities listed or
traded on the New York Stock Exchange, Inc., or if the Sprint Common Stock is
not so listed or admitted on such exchange, then on the exchange which is the
principal exchange on which the Sprint Common Stock is so listed or admitted,
or, if the Sprint Common Stock is not so admitted for trading on any national
securities exchange, the last sale price reported by the National Association of
Securities Dealers Automated Quotation System


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("NASDAQ") or if no such last sale prices are reported, the average of the last
reported closing bid and asked prices reported by NASDAQ.

     4.   Exercisability; Exercise.

          (a)  The Performance SAR shall become exercisable on June 9, 2002, and
may be exercised as hereinafter provided at any time thereafter to and including
June 8, 2007, provided that the conditions for exercisability set forth below
are met:

          (i)    If the fair market value of Sprint's common stock more than
                 doubles to equal or exceed $95.875 per share on any 30 trading
                 days within a consecutive period of 45 trading days, all of
                 which days fall after the fourth anniversary of the Grant Date
                 and on or before the fifth anniversary of the Grant Date, this
                 Performance SAR shall become 100% exercisable on the fifth
                 anniversary of the Grant Date.

          (ii)   If the conditions of clause (i) are not met, but the fair
                 market value of Sprint's common stock equals or exceeds $95.875
                 per share on any 30 trading days within a consecutive period of
                 45 trading days, all of which days fall after the fourth
                 anniversary of the Grant Date and on or before the sixth
                 anniversary of the Grant Date, this Performance SAR shall
                 become 100% exercisable on the last day of the 45-day period.

 
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          (iii)  If no such 45-day period occurs by the sixth anniversary of the
                 Grant Date, the Performance SAR shall be forfeited.

          (b)    The Executive shall forfeit the Performance SAR if, prior to
its becoming exercisable, his employment with the Company is terminated as
follows: (i) due to death, (ii) due to Disability (as defined in Section 13(b)
of the Employment Agreement), (iii) by the Company for Cause (as defined in
Section 13(c) of the Employment Agreement), or (iv) due to the Voluntary
Termination by the Executive (as defined in Section 13(e) of the Employment
Agreement). In the event that, prior to the Performance SAR's becoming
exercisable, the Executive's employment shall terminate due to a Termination
without Cause or Constructive Termination without Cause pursuant to Section
13(d) of the Employment Agreement, the Performance SAR shall immediately become
exercisable and shall remain exercisable for the period for which Base Salary is
continued pursuant to Section 13(d)(ii) plus 3 months. In the event that, prior
to the Performance SAR's becoming exercisable, there is a Change in Control of
Sprint (based on the definition of Change in Control as set forth in Section
1(e) of the Employment Agreement, but substituting "Sprint" for "the Company"),
the Performance SAR shall immediately become exercisable and shall remain
exercisable for the remainder of its term, subject to termination of

 
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employment, in which case the remaining exercisability shall be as provided in
Section 4(c) depending on the type of termination.

          (c)  For the period after the Performance SAR becomes exercisable, the
Performance SAR shall continue to be exercisable following a termination of the
Executive's employment with the Company pursuant to the applicable paragraphs of
the Employment Agreement, as follows, provided that in no event shall the
Performance SAR be exercisable after June 8, 2007: (i) due to death: for 12
months following death; (ii) due to Disability (as defined in Section 13(b) of
the Employment Agreement): for 60 months following termination; or (iii) due to
Termination Without Cause or Constructive Termination Without Cause (as defined
in Section 13(d) of the Employment Agreement) for the period for which Base
Salary is continued pursuant to section 13(d)(ii) plus 3 months (or if the event
triggering exercisability is a Change in Control of Sprint (based on the
definition of Change in Control as set forth in Section 1(e) of the Employment
Agreement, but substituting "Sprint" for "the Company"), for the period for
which Base Salary is continued pursuant to Section 13(f)(i)(A) plus 3 months).
In the event that, after the Performance SAR becomes exercisable, the
Executive's employment shall terminate due to a Termination by the Company for
Cause or a Voluntary Termination, pursuant to Section 13(c) or 13(e),
respectively, the Performance SAR shall be forfeited.

          (d)  The rights represented by this Performance SAR may be exercised
by the Executive, in whole or in part, by the surrender of this Agreement to the
Secretary of the Company 

 
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located at 3003 Butterfield Road, Oak Brook, IL 60523, or such other office or
agency of the Company as it may designate by notice in writing to the Executive
at the address of the Executive appearing on the books of the Company at the
time such notice was given. If the Performance SAR is exercised in part, the
Company shall note on this Agreement the number of Units as to which this
Agreement has been exercised and shall return this Agreement to the Executive.

     5.   Deferral of Gains. Anything in this Agreement to the contrary
notwithstanding, any gains on the exercise of the Performance SAR as realized by
the Executive when he is a Named Executive Officer of the Company (as defined in
the regulations promulgated under Internal Revenue Code Section 162(m)) shall be
deferred as provided in the following sentence. The gains being deferred, as
described in the preceding sentence, shall be deferred into the Company's Non-
Qualified Profit Sharing and Savings Plus Plan, or a successor plan, (the
"Deferral Plan") to the extent the Deferral Plan accepts such deferrals. If the
Deferral Plan is not available to accept such deferrals, the Participant may
make an irrevocable election to defer into (i) Share units (a unit representing
a Share of Common Stock of the Company including any dividends that may be
declared thereon during the period of the deferral) or (ii) deferred cash as to
which interest shall be credited and compounded annually based on the prime rate
as announced from time to time by Citibank N.A. Amounts deferred under clause
(i) or (ii) of the preceding sentence shall be paid out promptly following the
date on which 

 
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the Participant ceases to be a Named Executive Officer of the 
Company.
                                                                               
     6.   Adjustment of Base Value and Number of Units. If the number of
outstanding shares of Sprint Common Stock shall, at any time, be increased or
decreased as a result of (a) any subdivision or consolidation of shares, stock
dividend, stock split, recapitalization, reclassification or similar capital
adjustment or (b) any combination, exchange of shares or similar event arising
from Sprint's participation in any corporate merger, consolidation or similar
transaction in which Sprint is the surviving entity and is not substantially or
completely liquidated, the number of Units and the kind of shares represented by
the Units with respect to which the Option may thereafter be exercised and the
Base Value shall be appropriately adjusted.

     7.   Notices. Upon any adjustment of the number of Units pursuant to this
Performance SAR or the Base Value, the Company within twenty calendar days after
it learns of the event requiring such adjustment shall give written notice to
the Executive setting forth the adjusted number of Units and Base Value and
setting forth in reasonable detail the method of calculation and the facts upon
which such adjustment was made, which certificate shall be presumptive evidence
of the correctness of the matter set forth therein. Such notice shall be given
to the Executive at the Executive's address on the books of the Company by 
first-class mail, postage prepaid or overnight courier service.


 
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     8.   Non-transferability. The Performance SAR shall not be transferable by
the Executive other than by will or the laws of descent and distribution. During
his lifetime, the Performance SAR shall be exercisable only by the Executive or
his legal representative. Any attempt to transfer, assign, pledge, hypothecate
or otherwise dispose of the Performance SAR, other than as permitted herein,
shall be null and void and of no effect.

     9.   Successors and Assigns. This Agreement shall be binding upon, and
shall inure to the benefit of, the Company and its successors and assigns and
the Executive and his estate or other legal representatives.

     10.  References. In the event of the Executive's death or a judicial
determination of his physical or mental incompetence, references in this
Agreement to the Executive shall be deemed, where appropriate, to refer to his
estate or other legal representative.

     11.  Entire Agreement. This Agreement, together with the Employment
Agreement, contains the entire agreement between the parties concerning the
subject matter hereof and supersedes all prior agreements, understandings,
discussions, negotiations and undertakings, whether written or oral, between the
parties with respect thereto.

     12.  Amendment or Waiver. This Agreement cannot be changed, modified or
amended without the consent in writing of both the Executive and the Company. No
waiver by either party at any time of any breach by the other party of any
condition or provision of 

 
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this Agreement shall be deemed a waiver of a similar or dissimilar condition or
provision at the same or at any prior or subsequent time. Any waiver must be in
writing and signed by the Executive or an authorized officer of the Company, as
the case may be.

     13.  Tax Withholding. The Company shall have the power and the right to
deduct or withhold, or require a Participant to remit to the Company, an amount
sufficient to satisfy Federal, state and local taxes, domestic or foreign,
required by law or regulation to be withheld with respect to any taxable event
arising as a result of the Plan attributable to the Performance SAR.

     14.  Governing Law. This Agreement shall be governed by and construed and
interpreted in accordance with the laws of Illinois without reference to
principles of conflict of laws.

     15.  Headings. The headings of the sections contained in this Agreement are
for convenience only and shall not be deemed to control or affect the meaning or
construction of any provision of this Agreement.

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

                                       WASTE MANAGEMENT, INC.

                                       By: /s/ Herbert A. Getz 
                                          --------------------------
                                            Herbert A. Getz
                                            Senior Vice President
                                              and Secretary

                                           /s/ Ronald T. LeMay  
                                          --------------------------
                                            Ronald T. LeMay