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                                                                   EXHIBIT 10.25



                           NORCAL WASTE SYSTEMS, INC.

                 1996 EXECUTIVE STOCK INCENTIVE PLAN, AS AMENDED
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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                       Page
<S>      <C>                                                                             <C>
1.       Purpose.                                                                         1

2.       Definitions.                                                                     1

3.       Eligibility                                                                      1

4.       Stock Available for Plan.                                                        1

5.       Administration.                                                                  2

6.       Awards                                                                           3

7.       Options.                                                                         4

8.       Restricted Stock.                                                                7

9.       Stock Appreciation Rights.                                                       8

10.      Performance Awards.                                                             10

11.      Dividend Equivalent Rights.                                                     12

12.      Adjustment Upon Change in Capitalization.                                       13

13.      Restrictions on Transfer of Shares                                              13

14.      Company's Repurchase Option Upon Termination
           of Service                                                                    16

15.      Restrictions on Other Activities                                                17

16.      Withholding Taxes                                                               19

17.      Limitation of Rights                                                            19

18.      Non-Exclusivity of Plan                                                         21

19.      Duration and Amendment of Plan                                                  21

20.      Miscellaneous                                                                   21

Exhibit A:  Definitions                                                                 A-1
</TABLE>

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                           NORCAL WASTE SYSTEMS, INC.

                 1996 EXECUTIVE STOCK INCENTIVE PLAN, AS AMENDED


         1. Purpose.

                  The purpose of this Plan is (a) to enable the Company to
attract and retain executive officers and other selected Participants who are
important to the Company, and (b) to provide such persons with additional
incentive to advance the interests of the Company. Pursuant to this Plan, the
Committee will grant Awards which provide the Participants with a proprietary
interest in the long-term growth and performance of the Company. These Awards
may include Incentive Stock Options, Nonqualified Stock Options, Restricted
Stock, Stock Appreciation Rights, Performance Awards and Dividend Equivalent
Rights.

         2. Definitions.

                  Capitalized terms not otherwise defined in this Plan will have
the meanings set forth in Exhibit A to this Plan.

         3. Eligibility.

                  Awards will be granted only to persons who are officers,
employees or directors of the Company or any of its Affiliates, but will not be
granted to any person who does not satisfy the requirements of Section
25102(f)(2) of the California Corporate Securities Law of 1968 or similar
provisions of securities laws of other applicable states.

         4. Stock Available for Plan.

                  The maximum number of Shares available for Awards under this
Plan (the "Available Shares") is 2,887,500 subject to the following adjustments:

                  (a) When any Award (other than a Performance Unit denominated
in dollars) is granted, the Available Shares will be reduced by the number of
Shares set forth in such Award.

                  (b) When any portion of an Award (other than a Performance
Unit denominated in dollars) expires, is cancelled or is otherwise terminated
for any reason, the Available Shares will be increased by the Shares allocable
to the expired, cancelled or otherwise terminated portion of the Award.

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                  (c) If the Company ever repurchases Shares pursuant to this
Plan, the Available Shares will be increased by the number of such repurchased
Shares.

                  (d) Upon a change in capitalization, the number of Available
Shares will be adjusted in number and kind pursuant to Section 12.

         5. Administration.

                  (a) Committee Membership. This Plan will be administered by
the Committee, which will consist of two or more members of the Board. The
members of the Committee (i) will be appointed by the Board and (ii) may not be
employees of the Company. If no Committee has been appointed, the entire Board
will constitute the Committee.

                  (b) Committee Procedures. The Board will designate one of the
members of the Committee as chairperson. The Committee may hold meetings at such
times and places as it will determine. The acts of a majority of the Committee
members present at meetings at which a quorum exists, or acts approved in
writing by all Committee members, will be valid acts of the Committee.

                  (c) Committee Responsibilities. Subject to the provisions of
this Plan, the Committee will have full authority and discretion to take the
following actions:

                           (i) To determine when Awards are to be granted under
this Plan;

                           (ii) To select the Participants for each Award;

                           (iii) To determine the terms and conditions of each
Award;

                           (iv) To authorize any person to execute, on behalf of
the Company, any Award Agreement or other instrument required to carry out the
purposes of this Plan;

                           (v) To adopt, amend, waive or rescind rules,
procedures and restrictions relating to this Plan or to any Award;

                           (vi) To interpret this Plan and to apply its
provisions;

                           (vii) To determine whether a leave of absence will be
granted to a Participant without constituting a

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<PAGE>   5
termination of employment or service for purposes of the Plan;

                           (viii) To cause the Company to loan Participants
funds for any purpose related to this Plan, including to purchase any Shares or
to pay any taxes due with respect to any Award (with such loans to be granted
within the absolute discretion of the Committee and upon such terms as the
Committee may determine); and

                           (ix) To take any other action it deems necessary or
advisable for the implementation and administration of this Plan.

                  (d) Discretion. The presence in this Plan of specific
instances where the Committee has express discretion to make determinations with
respect to this Plan or to any Award (such as the discretion to extend the term
of an Option pursuant to Section 7(e)(v) below) does not imply that the
Committee does not have discretion to make other determinations not expressly
set forth in this Plan.

                  (e) Finality. All decisions, interpretations and other actions
of the Committee will be final and binding on all persons.

         6. Awards.

                  (a) General. The Committee will determine the type or types of
Award(s) to be made to each Participant. Awards may include but are not limited
to Options (which may be either Incentive Stock Options or Nonqualified Stock
Options), Restricted Stock, Stock Appreciation Rights, Performance Awards (which
may be either Performance Shares or Performance Units), or Dividend Equivalent
Rights; these Awards are further described in Sections 7 to 11, respectively.
Awards may be granted singly, in combination or in tandem. Awards may also be
made in combination or in tandem with, in replacement of, or as alternatives to,
grants or rights under any other employee plan of the Company, including the
plan of any entity acquired by the Company.

                  (b) Award Agreement. The terms of any Award will be set forth
in an Award Agreement. No Award will be effective until such Award Agreement is
executed and delivered by the Company and the Participant. The terms set forth
in this Plan will apply to any Award, except to the extent such terms are
expressly modified or deleted in such Award Agreement. The Award Agreement may
also contain other terms and restrictions not set forth in this Plan. If there
is any inconsistency between the terms of this Plan and the

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terms of the Award Agreement, the terms of the Award Agreement will control.

         7. Options.

                  (a) General. Subject to the provisions of this Plan, the
Committee will have full and final authority to grant Eligible Persons Options,
to determine whether such Options will be Incentive Stock Options or
Nonqualified Stock Options, and to determine all the terms applicable to such
Options. These terms will be set forth in an Award Agreement and will include
the following: (i) whether such Option is an Incentive Stock Option or
Nonqualified Stock Option; (ii) the number of Shares that may be purchased
pursuant to such Option; (iii) the vesting provisions for such Option; (iv) the
exercise price (or any formula for determining the exercise price); (v) the term
of such Option; and (vi) such other terms as the Committee determines.

                  (b) Incentive Stock Options. If the Committee grants an
Incentive Stock Option, such Option must comply with the requirements of Section
422 of the Code as in effect on the date of the grant. The Committee may amend
this Plan if it considers such amendment to be necessary or desirable to comply
with such requirements.

                  (c) Vesting. Each Option will become exercisable ("vest") in
such installments (which need not be equal) and at such times as may be
designated by the Committee and set forth in the Award Agreement. To the extent
not exercised, installments will accumulate and be exercisable, in whole or in
part, at any time after becoming exercisable, but not later than the date the
Option expires, as set forth in Section 7(e) below. Upon a Participant's
Termination of Service for any reason, the Option granted to such Participant
will cease to vest after such Termination Date (unless otherwise determined by
the Committee), and the Optionholder must exercise the vested portion of such
Option within the time periods set forth in Section 7(e) below. The Committee
may accelerate the exercisability of any Option or portion thereof at any time
for any reason.

                  (d) Exercise Price. The exercise price for Shares under each
Option will be determined by the Committee and set forth in the Award Agreement;
provided, however, that the exercise price for Shares must be at least 85% of
the Fair Market Value of the Shares as of the date such Option is granted,
unless the recipient of the Option is the owner of more than 10% of the total
combined voting power of all classes of stock of the Company, in which case the
exercise price must be at least 110% of such Fair Market Value.

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                  (e) Exercise Period. Options will be for such term as the
Committee will determine; provided, however, that the term of an Option may not
be greater than ten year from the date of grant of such Option. Unless the Award
Agreement provides otherwise, an Option's term will expire as follows:

                             (i) No Option will be exercisable more than ten
years after the date it is granted.

                             (ii) Upon a Participant's Termination of Service
for any reason other than Cause, Disability or death, the Optionholder may, for
a period of three months after such Termination Date, exercise the Option to the
extent, and only to the extent, that such Option was exercisable as of the
Termination Date, after which time the Option will automatically expire.

                             (iii) Upon a Participant's Termination of Service
for Cause, the Option granted to the Participant will immediately expire, and no
rights thereunder may be exercised.

                             (iv) Upon a Participant's Termination of Service
because of the Participant's Disability or death, the Optionholder may, for a
period of one year after such Termination Date, exercise the Option to the
extent, and only to the extent, that such Option was exercisable as of the
Termination Date, after which time the Option will automatically expire.

                             (v) The Committee may, subsequent to the granting
of any Option, extend the term thereof.

                  (f) Method of Exercise.

                             (i) The exercise of an Option will be made only by
a written notice delivered in person or by mail to the Secretary of the Company
at the Company's principal executive office, specifying the number of Shares to
be purchased and accompanied by payment therefor and otherwise in accordance
with the Award Agreement.

                             (ii) The exercise price for any Shares purchased
pursuant to the exercise of an Option will be paid in full in cash upon such
exercise, unless otherwise provided in the Award Agreement or unless otherwise
determined by the Committee. The Committee will have discretion to determine at
the time of grant of each Option or at any later date (up to and including the
date of exercise) that the form of payment acceptable in respect of the exercise
of such Option may consist of any of the following (or any combination thereof):
(A) cash, (B) promissory note (upon terms

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determined by the Committee), or (C) the transfer of Shares to the Company (upon
terms determined by the Committee). Any Shares transferred to the Company as
payment of the purchase price under an Option will be valued at their Fair
Market Value on the day preceding the date of exercise of such Option.
Notwithstanding anything herein to the contrary, a promissory note will not be
an acceptable form of payment in respect of the exercise of an Option from and
after the Initial Public Offering.

                           (iii) Options may also be exercised through a
registered broker-dealer pursuant to such cashless exercise procedures that may,
from time to time, be deemed acceptable by the Committee.

                           (iv) No fractional Shares (or cash in lieu thereof)
will be issued upon exercise of an Option, and the number of Shares that may be
purchased upon exercise will be rounded to the nearest number of whole Shares.

                  (g) Transferability of Options. An Optionholder may not
Transfer any Option except as follows:

                           (i) By will or under the laws of descent and
distribution; or

                           (ii) To one or more Permitted Transferees, provided
that (A) each such transferee executes such documents as the Committee may
require, agrees to be bound by this Plan and the Award Agreement, and
acknowledges that the status or conduct of the Participant to whom the Option
was granted may affect the transferee's rights under the Option (such as when
the Option ceases to vest or when any Shares may be repurchased by the Company),
and (B) the Company is satisfied that such Transfer complies with applicable
federal and state securities laws.

                  (h) Rights of Optionholder. No Optionholder will be deemed for
any purpose to be the owner of any Shares subject to any Option unless and until
(i) the Option will have been exercised pursuant to the terms of this Plan and
the Award Agreement, and (ii) the Company will have issued and delivered Shares
to the Optionholder. At that time, the Optionholder will have full voting,
dividend, and other ownership rights with respect to such Shares, subject to
such terms and conditions as may be set forth in this Plan and the Award
Agreement.

                  (i) Change in Control. Unless otherwise provided in the Award
Agreement, in the event of a Change in Control, the following terms will apply:

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                           (i) All Options outstanding on the date of such
Change in Control will become immediately and fully exercisable.

                           (ii) Subject to Section 17(d) below, an Optionholder
will be permitted to surrender for cancellation within 60 days after such Change
in Control any Option to the extent not yet exercised, and the Optionholder will
be entitled to receive a cash payment in an amount equal to the excess, if any,
of (A)(1) in the case of a Nonqualified Stock Option, the greater of (x) the
Fair Market Value, on the date preceding the date of surrender, of the Shares
subject to the Option or portion thereof surrendered (the "Surrendered Shares")
or (y) the Adjusted Fair Market Value of the Surrendered Shares or (2) in the
case of an Incentive Stock Option, the Fair Market Value, on the date preceding
the date of surrender, of the Surrendered Shares, over (B) the aggregate
exercise price for such Surrendered Shares; provided, however, that in the case
of an Option granted within six months prior to the Change in Control to any
Optionholder who may be subject to liability under Section 16(b) of the Exchange
Act, such Optionholder will be entitled to surrender for cancellation his Option
during the 60 day period beginning upon the expiration of six months from the
date of grant of any such Option.

         8. Restricted Stock.

                  (a) Grant. The Committee may grant Eligible Persons Restricted
Stock. Each Award Agreement will contain such terms as the Committee may, in its
discretion, determine, including terms relating to the lapse of any
restrictions. Unless the Award Agreement provides otherwise, Restricted Stock
will be subject to the terms set forth in this Section 8.

                  (b) Rights of Participant. Shares of Restricted Stock will be
issued in the name of the Participant as soon as reasonably practicable after
the Award is granted, provided that the Participant has executed an Award
Agreement, the appropriate blank stock powers and, in the discretion of the
Committee, an escrow agreement and any other documents which the Committee may
require as a condition to the issuance of such Shares. At the discretion of the
Committee, Shares issued in connection with a Restricted Stock Award will be
deposited together with the stock powers with an escrow agent (which may be the
Company) designated by the Committee. Unless the Committee determines otherwise,
upon delivery of the Shares to the escrow agent, the Participant will have all
of the rights of a shareholder with respect to such Shares, including the right
to vote the

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Shares and to receive all dividends paid with respect to the Shares.

                  (c) Change in Control. Unless otherwise provided in the Award
Agreement, the restrictions upon Shares of Restricted Stock will lapse upon a
Change in Control. The Award Agreement will set forth any such provisions.

                  (d) Treatment of Dividends. At the time Restricted Stock is
granted, the Committee may, in its discretion, determine that the payment to the
Participant of dividends, or a specified portion thereof, declared or paid on
such Shares by the Company will be (i) deferred until the lapsing of the
restrictions imposed upon such Shares and (ii) held by the Company for the
account of the Participant until such time. If dividends are to be deferred, the
Committee will determine whether such dividends are to be reinvested in shares
of Stock (which will be held as additional Shares of Restricted Stock) or held
in cash. If deferred dividends are to be held in cash, there may be credited at
the end of each year (or portion thereof) interest on the amount of the account
at the beginning of the year at a rate per annum as the Committee, in its
discretion, may determine.

         9. Stock Appreciation Rights.

                  (a) General. The Committee may in its discretion, either alone
or in connection with the grant of an Option, grant Eligible Persons Stock
Appreciation Rights in accordance with this Plan, the terms of which will be set
forth in an Award Agreement. If granted in connection with an Option, a Stock
Appreciation Right will cover the same Shares covered by the Option (or such
lesser number of Shares as the Committee may determine) and will, except as
provided in this Section 9, be subject to the same terms as the related Option.

                  (b) Time of Grant. A Stock Appreciation Right may be granted
(i) at any time if unrelated to an Option, or (ii) if related to an Option,
either at the time of grant, or at any time thereafter during the term of the
Option.

                  (c) Stock Appreciation Right Related to an Option.

                             (i)    Exercise.  A Stock Appreciation Right
granted in connection with an Option will be exercisable at such time or times
and only to the extent that the related Options are exercisable, and will not be
transferable except to the extent the related Option may be transferable. A
Stock Appreciation Right granted in connection with an Incentive Stock Option
will be exercisable only if the Fair

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Market Value of a Share on the date of exercise exceeds the exercise price
specified in the related Award Agreement.

                            (ii)    Amount Payable.  Upon the exercise of a
Stock Appreciation Right related to an Option, the Participant will be entitled
to receive an amount determined by multiplying (A) the excess of the Fair Market
Value of a Share on the date preceding the date of exercise of such Stock
Appreciation Right over the per Share exercise price under the related Option,
by (B) the number of Shares as to which such Stock Appreciation Right is being
exercised. Notwithstanding the foregoing, the Committee may limit in any manner
the amount payable with respect to any Stock Appreciation Right by including
such limit in the Award Agreement evidencing the Stock Appreciation Right at the
time it is granted.

                           (iii)    Treatment of Related Options and Stock
Appreciation Rights Upon Exercise. Upon the exercise of a Stock Appreciation
Right granted in connection with an Option, the Option will be cancelled to the
extent of the number of Shares as to which the Stock Appreciation Right is
exercised, and upon the exercise of an Option granted in connection with a Stock
Appreciation Right, the Stock Appreciation Right will be cancelled to the extent
of the number of Shares as to which the Option is exercised.

                  (d) Stock Appreciation Right Unrelated to an Option. The
Committee may grant to Eligible Persons Stock Appreciation Rights unrelated to
Options. Stock Appreciation Rights unrelated to Options will contain such terms
and conditions as to exercisability, vesting and duration as the Committee will
determine. Upon exercise of a Stock Appreciation Right unrelated to an Option,
the Participant's will be entitled to receive an amount determined by
multiplying (A) the excess of the Fair Market Value of a Share on the date
preceding the date of exercise of such Stock Appreciation Right over the Fair
Market Value of a Share on the date the Stock Appreciation Right was granted, by
(B) the number of Shares as to which the Stock Appreciation Right is being
exercised. Notwithstanding the foregoing, the Committee may limit in any manner
the amount payable with respect to any Stock Appreciation Right by including
such limit in the Award Agreement evidencing the Stock Appreciation Right at the
time it is granted.

                  (e) Form of Payment. Payment of the amount determined under
this Section 9 may be made in the discretion of the Committee solely in whole
Shares in a number determined at their Fair Market Value on the date preceding
the date of exercise of the Stock Appreciation Right, or solely in cash, or in a
combination of cash and Shares. If

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the Committee decides to make full payment in Shares and the amount payable
results in a fractional Share, payment for the fractional Share will be made in
cash.

                  (f) Change in Control. Unless otherwise provided in the Award
Agreement, in the event of a Change in Control, (i) all Stock Appreciation
Rights will become immediately and fully exercisable and (ii) the other terms
set forth in Section 7(i) with respect to Options will also apply to Stock
Appreciation Rights.

         10. Performance Awards.

                  (a) Performance Objectives. Performance Objectives for
Performance Awards may be expressed in whatever terms the Committee determines,
including (without limitation) (i) earnings per Share, (ii) pre-tax profits,
(iii) net earnings, (iv) return on equity or assets, (v) revenues, (vi) cash
flow or (vii) any combination of the foregoing. Performance Objectives may be in
respect of the performance of the Company and its subsidiaries (which may be on
a consolidated basis), a subsidiary, or a division. Performance Objectives may
be absolute or relative and may be expressed in terms of a progression within a
specified range.

                  (b) Performance Units.

                           (i) The Committee, in its discretion, may grant
Eligible Persons Performance Units, the terms of which will be set forth in an
Award Agreement. Performance Units may be denominated in Shares or in a
specified dollar amount. Contingent upon the attainment of specified Performance
Objectives within the Performance Cycle, Performance Units represent the right
to receive payment as follows: (A) in the case of Share-denominated Performance
Units, the Fair Market Value of a Share on the date the Performance Unit was
granted, the date the Performance Unit becomes vested, or any other date
specified by the Committee, (B) in the case of dollar-denominated Performance
Units, the specified dollar amount or (C) a percentage (which may be more than
100%) of the amount described in clause (A) or (B), depending on the level of
Performance Objective attainment; provided, however, that the Committee may at
the time a Performance Unit is granted specify a maximum amount payable in
respect of a vested Performance Unit. Each Award Agreement will specify the
number of Performance Units to which it relates, the Performance Objectives
which must be satisfied in order for the Performance Units to vest, and the
Performance Cycle within which such Performance Objectives must be satisfied;
provided, however, that satisfaction of any applicable Performance Objectives
will be made without regard to any

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change in accounting standards that may be required after the Performance
Objectives are established.

                           (ii) Vesting. Performance Units will become vested at
such time or times and on such terms, conditions and satisfaction of Performance
Objectives as the Committee may, in its discretion, determine at the time an
Award is granted.

                           (iii) Payment of Awards. Payment for vested
Performance Units will be made within 60 days after the last day of the
Performance Cycle to which such Award relates, unless the Award Agreement
provides for the deferral of payment. Such payments may be made entirely in
Shares valued at their Fair Market Value as of the last day of the applicable
Performance Cycle or such other date specified by the Committee, entirely in
cash, or in such combination of Shares and cash as the Committee in its
discretion will determine at any time prior to such payment.

                  (c) Performance Shares. The Committee, in its discretion, may
grant Eligible Persons Performance Shares, the terms of which will be set forth
in an Award Agreement between the Company and the Participant. Each Award
Agreement may require that an appropriate legend be placed on Share
certificates. Unless this Award Agreement provides otherwise, Performance Shares
will be subject to the following terms and provisions:

                             (i)    Rights of Participant.  At the time an
Award is made, the Committee will provide the time or times at which the actual
Shares represented by such Award will be issued in the name of the Participant;
provided, however, that no Performance Shares will be issued until the
Participant has executed an Agreement evidencing the Award, the appropriate
blank stock powers and, in the discretion of the Committee, an escrow agreement
and any other documents which the Committee may require as a condition to the
issuance of such Performance Shares. At the discretion of the Committee, Shares
issued in connection with an Award of Performance Shares will be deposited,
together with the stock powers, with an escrow agent (which may be the Company)
designated by the Committee. Upon delivery of the Shares to the escrow agent,
the Participant will have, in the discretion of the Committee, all of the rights
of a shareholder with respect to such Shares, including the right to vote the
Shares and to receive all dividends paid with respect to the Shares.

                           (ii) Lapse of Restrictions. Restrictions upon
Performance Shares awarded hereunder will lapse and such Performance Shares will
become vested at such time or times

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<PAGE>   14
and on such terms, conditions and satisfaction of Performance Objectives as the
Committee may, in its discretion, determine at the time an Award is granted.

                  (d) Effect of Change in Control. Unless the Award Agreement
provides otherwise, in the event of a Change in Control:

                           (i) With respect to Performance Units, the
Participant will (A) become vested in a percentage of Performance Units as set
forth in the Award Agreement and (B) be entitled to receive in respect of all
Performance Units which become vested as a result of a Change in Control, a cash
payment within ten days after such Change in Control in an amount as determined
by the Committee and as set forth in the Award Agreement.

                           (ii) With respect to Performance Shares, restrictions
will lapse immediately on all or a portion of the Performance Shares as set
forth in the Award Agreement.

                           (iii) The Award Agreement evidencing Performance
Units or Performance Shares will provide for the treatment of such Awards (or
portions thereof) which do not become vested as the result of a Change in
Control, including, but not limited to, provisions for the adjustment of
applicable Performance Objectives.

         11. Dividend Equivalent Rights.

                  Dividend Equivalent Rights may be granted to Eligible Persons
in tandem with another Award or as a separate Award. The terms applicable to
each Dividend Equivalent Right will be specified in an Award Agreement. Amounts
payable in respect of Dividend Equivalent Rights may be payable currently,
deferred until the lapsing of restrictions on such Dividend Equivalent Rights,
or deferred until the vesting, exercise, payment, settlement or other lapse of
restrictions on the Award to which the Dividend Equivalent Rights relate. If the
amount payable in respect of Dividend Equivalent Rights is to be deferred, the
Committee will determine whether such amounts are to be held in cash, reinvested
in Shares or deemed to be reinvested in Shares. If amounts payable in respect of
Dividend Equivalent Rights are to be held in cash, there may be credited at the
end of each year (or portion thereof) interest on the amount of the account at
the beginning of the year at a rate per annum as the Committee, in its
discretion, may determine. Dividend Equivalent Rights may be settled in cash or
Shares or a combination thereof, in a single installment or multiple
installments, as determined by the Committee.

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<PAGE>   15
         12. Adjustment Upon Change in Capitalization.

                  In the event of any change in the outstanding Shares of the
Company as a result of a stock split, reverse stock split, stock dividend or
distribution, recapitalization, combination or reclassification, the Committee
will conclusively determine the appropriate adjustments, if any, to be made with
respect to this Plan and any outstanding Awards, including (a) the maximum
number and class of Shares or other stock or securities with respect to which
Awards may be granted under this Plan, (b) the number and class of Shares or
other stock or securities which are subject to outstanding Awards granted under
this Plan and the exercise or purchase price therefor, if applicable, and (c)
the Performance Objectives. Any such adjustments will be made only by the
Committee, and when so made will be effective, conclusive and binding for all
purposes with respect to this Plan and all Awards then outstanding. No such
adjustments will be required by reason of the issuance or sale by the Company
for cash or other consideration of additional Shares or securities convertible
into or exchangeable for Shares.

         13. Restrictions on Transfer of Shares.

                  (a) General. A person who acquires Shares pursuant to the
exercise of an Option or pursuant to any other Award under this Plan (the
"Holder") may not Transfer all or any portion of such Shares, whether
voluntarily, involuntarily, or by operation of law, unless: (i) such Transfer
complies with all the terms of this Plan and the applicable Award Agreement,
including the right of first refusal set forth in Section 13(b) below, (ii) each
transferee executes such documents as the Committee may require, agrees to be
bound by this Plan and the applicable Award Agreement, and acknowledges that the
status or conduct of the Participant to whom the Award was originally granted
may affect the transferee's rights as a shareholder (such as when any Shares may
be repurchased by the Company); (iii) each transferee does not, directly or
indirectly, promote, participate, or engage in any activity or business
competitive with the Company; and (iv) the Company is satisfied that such
Transfer complies with applicable federal and state securities laws. Any attempt
to Transfer Shares will be void unless the provisions of this Plan and the
applicable Award Agreement are satisfied.

                  (b) Right of First Refusal.

                           (i) Applicable Transactions. The right of first
refusal ("ROFR") in this Section 13(b) will apply whenever the Holder intends
(or is required by operation of

                                      -13-
<PAGE>   16
law or otherwise) to sell, pledge or otherwise Transfer any Shares, except that
(A) this Section 13(b) will not apply to transfers by the Holder (1) by will or
under the laws of descent and distribution, or (2) to one or more Permitted
Transferees, and (B) this Section 13(b) will terminate upon the effective date
of the Company's Initial Public Offering.

                           (ii) Notice. Before making any voluntary transfer of
Shares, the Holder will give written notice to the Company. In the event of a
transfer by operation of law or other involuntary transfer, the transferee
promptly will give written notice to the Company. In either event, such notice
(the "ROFR Notice") must specify: (A) the proposed transferee(s); (B) the number
of Shares to be transferred (the "Applicable Shares"); (C) the consideration to
be received per Share; and (D) all other material terms relating to the proposed
transfer.

                           (iii) Consideration.

                                    (A) If the proposed transaction is a
transfer of Shares solely for cash, then the Company's option will be to
purchase all or any portion of the Applicable Shares upon the same terms and
conditions set forth in the ROFR Notice.

                                    (B) If the proposed transaction is a
transfer of Shares wholly or partially in exchange for property other than cash,
the purchase price of such Applicable Shares to the Company will be an amount in
cash equal to the fair market value of such property proposed to be received in
exchange for the Applicable Shares, as reasonably determined in good faith by
the Committee (plus the cash, if any, included in the consideration for such
Applicable Shares).

                                    (C) If the proposed transaction is a pledge
or other hypothecation of the ROFR Shares, or a gift or any other Transfer not
specifically described in Section 13(b)(iii)(A) or (B) above, then the Company's
option will be either: (1) to lend or otherwise Transfer to the Employee such
consideration as described in the ROFR Notice and otherwise to accept the
proposed Transfer of the Applicable Shares upon all the terms and conditions
stated therein; or (2) to purchase for cash all or any portion of the Applicable
Shares, in which case the purchase price will be the Fair Market Value for the
Applicable Shares, as determined by the Committee.

                                    (D) Whenever any determination of value must
be made by the Committee pursuant to this Section 13(b)(iii), the ROFR Notice
will be deemed delayed for all

                                      -14-
<PAGE>   17
time periods set forth in this Section 13 until such determination has been
made.

                           (iv) Exercise of ROFR.

                                    (A) The Company will have an assignable
option (but not an obligation) to purchase all or any portion of the Applicable
Shares. The Company may exercise this option by notifying the Holder of its
election to purchase all of the Applicable Shares within 30 days after the
receipt of the ROFR Notice.

                                    (B) If the Company elects within such 30 day
period to purchase all the Applicable Shares, the Holder will be obligated to
sell, and the Company (or its assignee) will be obligated to purchase, the
Applicable Shares for the consideration specified in Section 13(b)(iii) and
otherwise on the terms set forth in the ROFR Notice. All parties will use their
best efforts to consummate the transaction as promptly as possible.

                           (v) Non-Exercise of ROFR. The ROFR will not be deemed
exercised unless (i) the Company (or its assignee) elects within the applicable
time period specified above to purchase all of the Applicable Shares and (ii)
such purchase is consummated within 90 days after the Company's receipt of the
ROFR Notice. If the ROFR is not deemed exercised, the Holder may Transfer such
Applicable Shares to the proposed transferee(s) for a period of 60 days
following the first date on which the ROFR is not exercisable, provided that the
other terms of this Agreement are satisfied and that such Transfer is not more
favorable to the transferee(s) than the terms offered to the Company.

                  (c) Market Standoff. In connection with a firm commitment
underwritten public offering of securities of the Company, if requested by the
Company or its principal underwriter, each Holder of any Shares: (i) will not
Transfer any Shares not included in such underwriting during the 120-day period
(or such shorter or longer period as the underwriter may require of the
principal security holders of the issuer) following the effective date of the
registration statement filed with the Securities and Exchange Commission in
connection with such offering; and (ii) will execute such instruments as the
underwriter may reasonably require to evidence compliance with this Section.

                  (d) Escrow. For purposes of facilitating the enforcement of
the restrictions on Transfer and the rights of repurchase set forth in this Plan
or in any Award Agreement, the Committee may, at its discretion, require any
Holder of Shares to deliver the certificate(s) for such Shares with a

                                      -15-
<PAGE>   18
stock power executed by the Holder, in blank, to the Secretary of the Company or
his designee, to hold said certificate(s) and stock power(s) in escrow, and to
take all such actions and to effectuate all such Transfers or repurchases as are
in accordance with the terms of this Plan. The certificates may be held in
escrow so long as the Shares whose ownership they evidence are subject to any
Transfer restriction or right of repurchase under this Plan or under any Award
Agreement. Each Participant, by accepting an Award, acknowledges that the
Secretary of the Company (or his designee) is so appointed as the escrow holder
with the foregoing authorities as a material inducement to the grant of an Award
under the Plan, that the appointment is coupled with an interest, and that it
accordingly will be irrevocable.

         14. Company's Repurchase Option Upon Termination of Service.

                  (a) General. Upon a Termination of Service with respect to any
Participant, the Company will have an assignable option (but not an obligation)
(the "Repurchase Option"), to repurchase all or any portion of the Shares
acquired by the Participant (or any subsequent transferee) pursuant to the
exercise of an Option or pursuant to any other Award under this Plan. The
Company's Repurchase Option will be subject to Section 17(d) below and to the
rights of the Participant (or any subsequent transferee) to surrender any Award
pursuant to a Change in Control, such as the rights set forth in Section 7(i)
above.

                  (b) Repurchase Price.

                           (i) For any Termination of Service other than for
"Cause," the repurchase price will be the Fair Market Value of the Shares being
repurchased, as of the Termination Date.

                           (ii) For any Termination of Service for "Cause," the
repurchase price will be the lower of (A) the Fair Market Value of the Shares
being repurchased, as of the Termination Date, or (B) the purchase price paid to
the Company for such Shares.

                  (c) Payment. The repurchase price may be paid, at the option
of the Company, by any of the following means, or any combination of the
following means: (i) cash; (ii) cancellation of all or any portion of any
outstanding indebtedness owed by the Holder to the Company; or (iii) an
unsecured promissory note, with the following terms: interest at the prime rate,
payable annually; principal payable in five equal installments, with the first
payment

                                      -16-
<PAGE>   19
due within one year and the last payment within five years of the Termination
Date; and no prepayment penalties.

                  (d) Procedures for Exercise of Repurchase Option. The Company
may exercise the Repurchase Option itself or assign the Repurchase Option to one
or more other persons, including the other shareholders of the Company. Within
60 days after the Fair Market Value of the Shares has been determined, the
Company will notify the Holder if it wishes to exercise its Repurchase Option,
or if it has assigned the Repurchase Option to other persons who wish to
exercise such Repurchase Option. Such notice will set a date for the closing of
the transaction not later than 30 days from the date of such notice.

         15. Restrictions on Other Activities.

                  (a) General.

                           (i) Unless the Award Agreement provides otherwise,
any Award of Options or Restricted Stock will be subject to this Section 15. The
Award Agreement for any Award not involving Options or Restricted Stock will set
forth whether, and to what extent, the provisions of this Section 15 apply to
such Award.

                           (ii) Subject to Section 15(a)(i), if any Participant
breaches any provision set forth in this Section 15, the Company may, in its
discretion, (A) cancel any unexercised, unexpired, unpaid or deferred portions
of any Awards, and (B) subject to Section 17(d) below, repurchase any Shares
that were acquired by the Participant (or any subsequent transferee) pursuant to
the exercise of an Option or pursuant to the grant of Restricted Stock, with the
repurchase price for such Shares being an amount equal to the price paid to the
Company for such Shares. In addition, subject to Section 17(d) below, the
Company will have an assignable option (but not an obligation) to repurchase any
other Shares held by the Participant (or any subsequent transferee), with the
purchase price for such Shares being their Fair Market Value. Any payments for
such repurchase will be upon the same terms set forth in Section 14(c), and any
such repurchase will be exercised pursuant to the procedures set forth in
Section 14(d) above.

                  (b) Noncompetition. During the Restrictive Period, the
Participant will not carry on or engage as an Interested Party in any business
within the Territory that competes, directly or indirectly, with the Business of
the Company.

                                      -17-
<PAGE>   20
                  (c) Assistance to Acquiror. During the Restrictive Period, the
Participant will not become associated with (whether through an investment of
capital or otherwise), provide services to, or otherwise solicit, aid, assist or
cooperate with any person, group or entity (an "Acquiror") in any effort to
effect a Change in Control transaction with respect to the Company. Nothing in
this Section 15(c) will be construed to preclude such Participant from owning
less than 1% of the outstanding common stock of an Acquiror if the Acquiror's
stock is publicly traded and the Participant acquires such stock in the open
market.

                  (d) Solicitation of Customers. During the Restrictive Period,
the Participant will not engage in any unfair competition with the Company.
During the Restrictive Period, the Employee will not, without the prior written
consent of the Company, directly or indirectly disclose to any person, the names
or addresses of any of the Company's customers, clients and other business
associates or any other information pertaining to them, or call on, solicit or
take away any of the Company's customers, clients or other business associates,
either for the Participant or for any other person.

                  (e) Solicitation of Employees and Others. During the
Restrictive Period, the Participant will not, without the prior written consent
of the Company, directly or indirectly seek to persuade any director, officer or
employee of the Company to discontinue his or her position with such entity or
to become employed or engaged in any activity competitive with the Business of
the Company.

                  (f) Confidential Information.

                           (i) The Participant will use the Company's
Confidential information exclusively for the benefit of the Company, and for no
other purpose whatsoever. The Participant will not disclose any Confidential
Information to any person unless: (A) such disclosure is in connection with his
employment with the Company; (B) the Participant first obtains the prior written
consent of the Company; or (C) the Participant is required by law to disclose
such Confidential Information.

                           (ii) If the Participant or any of his agents are
requested or required by oral questions, interrogatories, depositions, requests
for information or documents in legal proceedings, subpoena, civil investigative
demand or other similar process to disclose any part of the Confidential
Information, the Participant will immediately notify the Company in writing of
the existence, terms and circumstances surrounding such a request or requirement
so that the Company

                                      -18-
<PAGE>   21
may take such steps as it deems necessary or appropriate to protect the
confidentiality of the Confidential Information. If, in the written opinion of
the Participant's counsel, disclosure of any Confidential Information by the
Participant or any of his agents is nonetheless legally required, the
Participant or his agents may disclose to such tribunal only that portion of the
Confidential Information which such counsel advises is legally required to be
disclosed. The Participant will exercise his or her best efforts to preserve the
confidentiality of the Confidential Information, including without limitation,
cooperating with the Company to obtain an appropriate protective order or other
reliable assurance that confidential treatment will be accorded to the
Confidential Information by such tribunal and the parties before it.

                  (g) Adverse Actions. During the Restrictive Period, the
Participant will not take any action or omit to take any action that the
Participant knows or reasonably should know is likely to adversely affect the
Company in a material manner.

         16. Withholding Taxes.

                  (a) General. When a Participant recognizes taxable income in
connection with any Award (a "Taxable Event"), the Participant will pay to the
Company an amount equal to the federal, state and local income taxes and other
amounts as may be required by law to be withheld by the Company in connection
with the Taxable Event (the "Withholding Taxes") prior to the issuance, or
release from escrow, of Shares or the payment of cash. The Company will have the
right to deduct from any payment of cash to a Participant an amount equal to the
Withholding Taxes.

                  (b) Tax Election. A Participant may make a written election
(the "Tax Election"), which may be accepted or rejected in the discretion of the
Committee, to have withheld a portion of the Shares then issuable to the
Participant having an aggregate Fair Market Value, on the date preceding the
date of such issuance, equal to the Withholding Taxes. The Committee may, by the
adoption of rules or otherwise, impose such restrictions or limitations on Tax
Elections as it considers appropriate, including restrictions required to comply
with Section 16(b) of the Exchange Act.

         17. Limitation of Rights.

                  (a) Employment Rights. Neither this Plan nor any Award granted
under this Plan will give any individual a right to remain employed by the
Company. The Company

                                      -19-
<PAGE>   22
reserves the right to terminate the employment of any employee at any time, with
or without Cause.

                  (b) Shareholder Rights. A Participant will have no dividend
rights, voting rights or other rights as a shareholder with respect to any
Shares covered by his or her Award prior to the issuance of a stock certificate
for such Shares.

                  (c) Creditor Rights; Unfunded Plan. Insofar as it provides for
Awards of Shares or cash, this Plan will be unfunded. Although bookkeeping
accounts may be established with respect to Participants who are entitled to
Shares, cash, or rights thereto under the Plan, any such accounts will be used
merely as a bookkeeping convenience. The Company will not be required to
segregate any assets that may at any time be represented by Shares, cash, or
rights thereto, nor will the Company, the Board or the Committee be deemed to be
a trustee of any Shares, cash, or rights thereto to be granted under the Plan.
Any liability of the Company to any Participant with respect to a grant of
Shares, cash, or rights thereto under the Plan will be based solely upon any
contractual obligation that may be created by the Plan and any Award Agreement;
no such obligation of the Company will be deemed to be secured by any pledge or
other encumbrance on any property of the Company.

                  (d) Restricted Payments. Notwithstanding any other provision
of this Plan, the Company will not purchase, redeem or otherwise acquire or make
payments with respect to Shares or Options if and to the extent such payments
are restricted by (i) the Indenture dated as of November 21, 1995 among the
Company, its Affiliates and IBJ Schroeder Bank & Trust Company, as trustee, (ii)
the Revolving Credit Agreement dated as of November 21, 1995 among the Company,
its Affiliates and First National Bank of Boston, (iii) other credit agreements
the Company may enter into in the future, or (iv) applicable law, including but
not limited to Section 500 et seq. of the California Corporations Code.

                  (e) Government Regulations. Any other provision of this Plan
notwithstanding, the obligations of the Company with respect to Shares to be
issued pursuant to the Plan will be subject to all applicable laws, rules and
regulations, and such approvals as may be required by any governmental agencies.
The Company reserves the right to restrict, in whole or in part, the delivery of
Shares pursuant to any Award until such time as any legal requirements or
regulations have been satisfied relating to the issuance of such Shares,
including their registration, qualification or exemption from registration or
qualification under the Securities Act or any applicable state securities laws.

                                      -20-
<PAGE>   23
                  (f) Pooling Transaction. Notwithstanding any other provision
of this Plan, in the event of a Change in Control which is also intended to
constitute a pooling transaction for accounting purposes, the Participant and
Committee will negotiate in good faith such changes that are deemed reasonably
necessary by the Company's accountants to assure that the transaction qualifies
as a pooling transaction.

         18. Non-Exclusivity of Plan.

                  The adoption of this Plan will not be construed as amending,
modifying or rescinding any previously approved incentive arrangement or as
creating any limitations on the power of the Board to adopt such other incentive
arrangements as it may deem desirable, including, without limitation, the
granting of stock options otherwise than under this Plan, and such arrangements
may be either applicable generally or only in specific cases.

         19. Duration and Amendment of Plan.

                  (a) Term of the Plan. The Plan will become effective on the
date it is adopted by the Board of Directors. The Plan will remain in effect for
ten years, unless it is terminated earlier pursuant to Section 19(b).

                  (b) Amendment or Termination. The Committee may, at any time
and for any reason, amend or terminate this Plan; provided, however, that (i)
any amendment of this Plan will be subject to the approval of the Company's
shareholders to the extent required by applicable laws, regulations or rules;
(ii) no amendment or termination of this Plan may adversely affect the rights of
Participants under Awards that were granted before such amendment or
termination; and (iii) any amendment of this Plan that would (A) increase the
number of Available Shares as set forth in Section 4, (B) modify the requirement
set forth in Section 5(a) that members of the Committee may not be employees of
the Company or (C) modify any provisions hereof expressly restricting the term
of any Award hereunder, will, in the case of clauses (A), (B) and (C) above, be
subject to the approval of the outstanding shares of the Company (as such term
is defined in Section 152 of the California General Corporation Law).

                  (c) Public Company. In connection with an Initial Public
Offering, the Committee may amend this Plan to comply with the requirements of
Section 162(m) of the Code and Rule 16b-3 under the Exchange Act.

                                      -21-
<PAGE>   24
         20. Miscellaneous.

                  (a) Notice. Any notice to the Company required by any
provision of this Plan will be addressed to the Secretary of the Company in
writing, and will become effective when it is received by such person.

                  (b) Severability. If any provision of this Plan is deemed
invalid, illegal, or unenforceable, such provision will be deemed amended to the
extent necessary to conform to applicable law so as to be valid, legal and
enforceable; if such provision cannot be amended as provided above, it will be
stricken and the remainder of this Plan will remain in full force and effect.

                  (c) Governing Law. This Plan and all determinations made and
actions taken pursuant to this Plan, to the extent not otherwise governed by the
laws of the United States, will be governed by the laws of the State of
California and will be construed accordingly.

                                      -22-
<PAGE>   25
                           NORCAL WASTE SYSTEMS, INC.

                       1996 EXECUTIVE STOCK INCENTIVE PLAN


                                    Exhibit A

                                   Definitions

                  For purposes of this Plan, the following terms are defined as
follows:

                  "Adjusted Fair Market Value" means, in the event of a Change
in Control, the greater of (a) the highest price per Share paid to holders of
the Shares in any transaction (or series of transactions) constituting or
resulting in a Change in Control, or (b) the highest Fair Market Value of a
Share during the 90 day period ending on the date of a Change in Control.

                  "Affiliate" means any corporation or other entity (including,
but not limited to, partnerships and joint ventures) controlling, controlled by
or under common control with the Company.

                  "Available Shares" has the meaning set forth in Section 4.

                  "Award" means the grant of any equity-based compensation to
Eligible Persons pursuant to this Plan, which includes but is not limited to an
Option, Restricted Stock, a Stock Appreciation Right, a Performance Award or a
Dividend Equivalent Right.

                  "Award Agreement" means the written agreement between the
Company and a Participant evidencing the grant of an Award and setting forth the
terms of such Award.

                  "Board" means the Board of Directors of the Company.

                  "Business" means (a) any aspect of the waste management
business, including refuse collecting, recycling and other waste diversion,
transfer station and hauling operations, or operation of landfills, or (b) any
other business then conducted by the Company during the applicable Restrictive
Period, or, if substantial time or resources have been devoted to a proposed
business, as proposed to be conducted by the Company at such time.

                                       A-1
<PAGE>   26
                  "Cause" means termination of a Participant's employment with,
or service to, the Company for any one or more of the following reasons: (a)
willful misconduct which adversely affects the Company in a material manner; (b)
willful and material failure to perform reasonably assigned duties after written
notice from the Board; (c) conviction of a felony; or (d) breach of any material
provision of the Award Agreement.

                  A "Change in Control" means the occurrence of any of the
following:

                  (a) Any "Person" (which includes a "group," as the terms
person and group are used for purposes of Section 13(d) or 14(d) of the Exchange
Act) obtains "Beneficial Ownership" (within the meaning of Rule 13d-3
promulgated under the Exchange Act) of the "Requisite Percentage" (as defined
below) of the combined voting power of the Company's then outstanding voting
securities ("Voting Securities"); provided, however, in determining whether a
Change in Control has occurred, Voting Securities which are acquired in a "Non-
Control Acquisition" (as hereinafter defined) will not constitute an acquisition
which would cause a Change in Control. The "Requisite Percentage" means 35% or
more of the Company's then outstanding Voting Securities if the Company has not
had its Initial Public Offering and 25% or more of the Company's then
outstanding Voting Securities if the Company has had its Initial Public
Offering. A "Non-Control Acquisition" means an acquisition by (i) an employee
benefit plan (or a trust forming a part thereof) maintained by (A) the Company
or (B) any corporation or other Person of which a majority of its voting power
or its voting equity securities or equity interest is owned, directly or
indirectly, by the Company (for purposes of this definition, a "Subsidiary") or
(ii) the Company or its Subsidiaries, or (iii) any Person in connection with a
"Non-Control Transaction" (as hereinafter defined);

                  (b) The individuals who, as of the date this Plan is adopted,
are members of the Board (the "Incumbent Board"), cease for any reason to
constitute at least two-thirds of the members of the Board; provided, however,
that if the election, or nomination for election by the Company's common
stockholders, of any new director is approved by a vote of at least two-thirds
of the Incumbent Board, such new director will, for purposes of this Plan, be
considered as a member of the Incumbent Board; provided further, however, that
no individual will be considered a member of the Incumbent Board if such
individual initially assumed office as a result of either an actual or
threatened "Election Contest" (as

                                       A-2
<PAGE>   27
described in Rule 14a-11 promulgated under the Exchange Act) or other actual or
threatened solicitation of proxies or consents by or on behalf of a Person other
than the Board (a "Proxy Contest"), including by reason of any agreement
intended to avoid or settle any Election Contest or Proxy Contest;

                  (c) At any time prior to the Company's Initial Public
Offering, the ESOP no longer owns more than 50% of the Company's then
outstanding Voting Securities; or

                  (d) The consummation of:

                           (i) a merger, consolidation or reorganization
involving the Company, unless such merger, consolidation or reorganization is a
"Non-Control Transaction." A "Non-Control Transaction" means a merger,
consolidation or reorganization of the Company where:

                                    (A) the shareholders of the Company,
immediately before such merger, consolidation or reorganization, own directly or
indirectly immediately following such merger, consolidation or reorganization,
at least 75% of the combined voting power of the outstanding voting securities
of the corporation resulting from such merger or consolidation or reorganization
(the "Surviving Corporation") in substantially the same proportion as their
ownership of the Voting Securities immediately before such merger, consolidation
or reorganization;

                                    (B) the individuals who were members of the
Incumbent Board immediately prior to the execution of the agreement providing
for such merger, consolidation or reorganization constitute at least two-thirds
of the members of the board of directors of the Surviving Corporation, or a
corporation beneficially directly or indirectly owning a majority of the Voting
Securities of the Surviving Corporation; and

                                    (C) no Person (other than (1) the Company,
(2) any Subsidiary, (3) any employee benefit plan (or any trust forming a part
thereof) maintained by the Company, the Surviving Corporation, or any
Subsidiary, or (4) any Person who, immediately prior to such merger,
consolidation or reorganization had Beneficial Ownership of the Requisite
Percentage of the then outstanding Voting Securities), has Beneficial Ownership
of the Requisite Percentage of the combined voting power of the Surviving
Corporation's then outstanding voting securities.

                           (ii) A complete liquidation or dissolution of the
Company; or

                                       A-3
<PAGE>   28
                           (iii) The sale or other disposition of all or
substantially all of the assets of the Company to any Person (other than a
transfer to a Subsidiary in which the Company retains at least 80% of the voting
securities and the value of ownership interests in such Subsidiary).

                  Notwithstanding the foregoing, a Change in Control will not be
deemed to occur solely because any Person (the "Subject Person") acquired
Beneficial Ownership of more than the permitted amount of the then-outstanding
Voting Securities as a result of the acquisition of Voting Securities by the
Company which, by reducing the number of Voting Securities then outstanding,
increases the proportional number of shares Beneficially Owned by the Subject
Person, provided that if a Change in Control would occur (but for the operation
of this sentence) as a result of the acquisition of Voting Securities by the
Company, and after such share acquisition by the Company, the Subject Person
becomes the Beneficial Owner of any additional Voting Securities which increases
the percentage of the then-outstanding Voting Securities Beneficially Owned by
the Subject Person, then a Change in Control will occur.

                  "Code" means the Internal Revenue Code of 1986, as amended.

                  "Committee" means a committee, as described in Section 5(a),
appointed by the Board to administer this Plan and to perform the functions set
forth in this Plan.

                  "Company" means Norcal Waste Systems, Inc. ("Norcal"), and its
subsidiaries, including subsidiaries of subsidiaries and partnerships and other
business ventures in which Norcal has a significant equity interest, as
determined in the sole discretion of the Committee.

                  "Confidential Information" means all information belonging to
the Company, its customers, clients or business associates, which information is
protectible as a trade secret under California law, and which may include
without limitation, business, marketing, distribution and purchasing plans,
techniques and strategies; financial statements, budgets, projections, prices,
and costs; customer lists; and know-how, formulae, discoveries, and inventions.

                  "Disability" means that the Company has determined, based on
competent medical evidence, that a Participant has become incapable, mentally or
physically, of substantially performing his services and substantially
discharging his duties to the Company for a period which has lasted, or can
reasonably be expected to last, for at least six months.

                                       A-4
<PAGE>   29
                  "Dividend Equivalent Right" means a right to receive all or
some portion of the cash dividends that are or would be payable with respect to
Shares.

                  "Eligible Person" means a person eligible to receive an Award
pursuant to Section 3 of this Plan.

                  "ESOP" means the Norcal Waste Systems, Inc. Employee Stock
Ownership Plan.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

                  "Fair Market Value" means, with respect to the Shares and as
of the date that is relevant to such determination, the price per Share
determined by the Committee pursuant to the following standards: (a) if the
Shares are traded on a stock exchange on the date in question, then the Fair
Market Value will be equal to the closing price reported by the applicable
composite-transactions report for such date; (b) if the Shares are traded
over-the-counter on the date in question and are classified as a national market
issue, then the Fair Market Value will be equal to the last-transaction price
quoted by the Nasdaq system for such date; (c) if the Shares are traded
over-the-counter on the date in question but are not classified as a national
market issue, then the Fair Market Value will be equal to the mean between the
last reported representative bid and asked prices quoted by the Nasdaq system
for such date; and (d) if none of the foregoing provisions is applicable, then
the Fair Market Value will be the value established by the Committee in good
faith, which value may be (i) the most recent per-Share valuation obtained by
the ESOP from third-party consultants in connection with the ESOP's annual
allocation of Shares, or (ii) a more recent per-Share valuation obtained by the
Committee, at its discretion, from an independent valuation expert.

                  "Holder" means a person who acquires Shares pursuant to the
exercise of an Option or pursuant to any other Award.

                  "Incentive Stock Option" means an Option satisfying the
requirements of Section 422 of the Code and designated by the Committee as an
Incentive Stock Option.

                  "Initial Public Offering" means the consummation of the first
underwritten public offering of Shares pursuant to a registration statement
(other than on Form S-8 or successor forms) filed with, and declared effective
by, the Securities and Exchange Commission.

                                       A-5
<PAGE>   30
                  "Interested Party" means an owner, shareholder (other than of
less than 1% of the outstanding shares of any publicly-held class of stock),
partner, creditor, director, officer, agent, manager, operator, salesman,
employee or any other participant in any capacity that calls for the rendering
of personal services, advice or acts of management, operation or control.

                  "Nonqualified Stock Option" means an Option which is not an
Incentive Stock Option.

                  "Option" means a Nonqualified Stock Option or an Incentive
Stock Option granted pursuant to Section 7.

                  "Optionholder" means a person holding an Option, who may be
either the Participant to whom the Option was initially granted or any
subsequent transferee permitted under this Plan.

                  "Participant" means a person to whom an Award has been granted
pursuant to this Plan.

                  "Performance Awards" means Performance Units, Performance
Shares or either or both of them.

                  "Performance Cycle" means the time period specified by the
Committee at the time Performance Awards are granted during which the
performance of the Company, a subsidiary or a division will be measured.

                  "Performance Objectives" has the meaning set forth in
Section 10.

                  "Performance Shares" means Shares issued or transferred to a
Participant under Section 10.

                  "Performance Unit" means Performance Units granted to a
Participant under Section 10.

                  "Permitted Transferee" means a Participant's ancestors,
descendants or spouse (other than pursuant to a decree of divorce, dissolution
or separate maintenance, a property settlement, or a separation agreement or any
similar agreement or arrangement with a spouse which is not for bona fide estate
planning purposes), or a trust, partnership, custodianship or other fiduciary
account primarily for the benefit of the Participant and/or such ancestors,
descendants or spouse.

                  "Plan" means this Norcal Waste Systems, Inc. 1996 Executive
Stock Incentive Plan, as it may be amended from time to time.

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<PAGE>   31
                  "Restricted Stock" means Shares issued to a Participant
pursuant to Section 8.

                  "Restrictive Period" means (a) the period the Participant is
employed by, or providing services to, the Company; and (b) the period beginning
on the Termination Date and continuing until the earlier of (i) three years
after such date, or (ii) such time as neither the Company nor any person
acquiring the goodwill or the stock of the Company carries on a substantially
similar Business within the Territory.

                  "Securities Act" means the Securities Act of 1933, as amended.

                  "Shares" means the common stock, par value $.01 per share, of
the Company.

                  "Stock Appreciation Right" means a right to receive all or
some portion of the increase in the value of the Shares, as provided in
Section 9.

                  "Termination Date" means the date on which a Termination of
Service occurs.

                  "Termination of Service" means a Participant ceases to be an
Eligible Person, such as when an employee's employment is terminated for any
reason.

                  "Territory" means, at any particular time, each and every city
and county within California or any other state where the Company is carrying on
or proposes to carry on its Business.

                  "Transfer" includes, without limitation, a voluntary or
involuntary sale, assignment, transfer, conveyance, pledge, hypothecation,
encumbrance, or other disposition of Awards or Shares.

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