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                                                                     EXHIBIT 4.6


             THE NOVA CHEMICALS CORPORATION DEFERRED SHARE UNIT PLAN
                                FOR KEY EMPLOYEES


SECTION 1.        PURPOSE

The purpose of the NOVA Chemicals Corporation Deferred Share Unit Plan for Key
Employees is to significantly strengthen the link between employee and
shareholder interests by encouraging Key Employees to voluntarily elect to have
a portion of their compensation tied to the long term performance of the Shares.

SECTION 2.        DEFINITIONS

For the purposes of the Plan:

(a)  "Affiliate" means an Affiliate of the Corporation as that term is defined
     in paragraph 3 of Revenue Canada's Interpretation Bulletin IT-337R3,
     RETIRING ALLOWANCES;

(b)  "Aggregate Purchase Price" has the meaning assigned thereto in Section 9
     hereof;

(c)  "Agreement" means the agreement as it may be amended from time to time,
     entered into by the Corporation and an Eligible Key Employee pursuant to
     Sections 6 and 6.1 hereof in connection with the grant of an award of Bonus
     DSUs and/or Discretionary DSUs hereunder to said Eligible Key Employee and
     setting forth the related rights and obligations of the Corporation and of
     the Eligible Key Employee;

(d)  "Board" means the Board of Directors of the Corporation;

(e)  "Bonus DSU" means a unit credited by means of a bookkeeping entry on the
     books of the Corporation to a Participant's account which is granted in
     accordance with Section 6 and administered in accordance with the terms and
     conditions of the Plan, the value of which on a particular date, shall be
     equal to the Market Value of a Share;

(f)  "Broker" has the meaning assigned thereto in Section 13 hereof;

(g)  "Change in Control" means any change in the holding, direct or indirect, of
     the securities of the Corporation as a result of which a person (as defined
     in the Alberta Business Corporations Act), or a group of persons, are in a
     position to exercise effective control of the Corporation;

(h)  "Committee" means the committee of directors of the Corporation whose
     mandate includes all executive compensation matters and which is currently
     named the Human Resources Committee;


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(i)  "Conversion Date" means, with respect to any calendar year, the date used
     to determine the Market Value of a Share for purposes of determining the
     number of Bonus DSUs to be credited in respect of that year to a Key
     Employee's account, which date shall be the last business day in the year
     immediately preceding the Performance Period;

(j)  "Corporation" means NOVA Chemicals Corporation;

(k)  "Disability Date" means in respect of a Participant, the date as of which
     he or she, as applicable, commences receiving or is eligible to receive
     long term disability benefits under the long term disability plan provided
     by the Corporation or an Affiliate of the Corporation;

(l)  "Discretionary DSU", means a unit credited by means of a bookkeeping entry
     on the books of the Corporation to a Participant's account which is granted
     in accordance with Section 6.1 and administered in accordance with the
     terms and conditions of the Plan, the value of which, on a particular date,
     shall be equal to the Market Value of a Share;

(m)  "Eligible Key Employee" has the meaning assigned thereto in Section 4
     hereof;

(n)  "Entitlement Date" has the meaning assigned thereto in Section 9 hereof;

(o)  "Global Dollar Amount" has the meaning assigned thereto in Section 7
     hereof;

(p)  "Key Employee" includes an officer or other employee of the Corporation or
     of any Affiliate of the Corporation who, in the opinion of the Committee,
     has demonstrated a capacity for contributing in a substantial measure to
     the successful performance of the Corporation or of such Affiliate;

(q)  "Management Incentive Compensation" means cash awards under the
     Corporation's Management Incentive Plan, based on corporate and business
     unit performance and individual contribution to the Corporation's results,
     measured against predetermined objectives, that may be payable to an
     employee of the Corporation or an Affiliate in respect of a Performance
     Period;

(r)  "Market Value" of one Share on any particular day means the average of the
     closing prices for a board lot of Shares on The Toronto Stock Exchange on
     the five (5) trading days immediately preceding the particular date, or if
     at least one board lot of Shares shall not have been traded on The Toronto
     Stock Exchange on any such day, on the immediately preceding day for which
     at least one board lot was so traded; or if, at any time, the Shares are no
     longer listed on The Toronto Stock Exchange, then the Market Value shall be
     calculated on the basis of the average closing price, as aforesaid, for a
     board lot of Shares on the stock exchange on which the Shares are listed
     and had the greatest volume of trading during such five day period. The
     Market Value shall always depend on the fair market value of a Share or a
     share of a corporation related to the Corporation;

(s)  "Participant" means an Eligible Key Employee who has been granted Bonus
     DSUs or Discretionary DSUs under the Plan;


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(t)  "Plan" means the NOVA Chemicals Corporation Deferred Share Unit Plan for
     Key Employees, as amended from time to time;

(u)  "Performance Period" means a calendar year in respect of which an Eligible
     Key Employee may be or become entitled to an award of Bonus DSUs or
     Management Incentive Compensation, or both;

(v)  "Price per Share" has the meaning assigned thereto in Section 9 hereof;

(w)  "Share" means a common share without nominal or par value, of the capital
     stock of the Corporation;

(x)  "Termination Date" means the earliest date on which both of the following
     conditions are met: the Key Employee (1) has ceased to be employed by the
     Corporation or any Affiliate for any reason whatsoever, including
     termination of employment by the employer (whether or not for cause),
     voluntary resignation, retirement from active employment or death of the
     Key Employee, and (2) is not a Director of the Board or of the board of an
     Affiliate.

SECTION 3.        ADMINISTRATION OF THE PLAN

Subject to Sections 5, 6, 6.1, and 12 hereof, the Plan shall be administered by
the Committee, beginning with the 1999 calendar year, the whole subject to
applicable corporate and securities law requirements. The Committee shall have
full and complete authority to interpret the Plan, to prescribe such rules and
regulations (including those with respect to the holding of meetings by
telephone) and to make such other determinations as it deems necessary or
desirable for the administration of the Plan. All actions taken and decisions
made by the Committee shall be final, conclusive and binding on all parties
concerned, including, but not limited to, the Participants and their
beneficiaries and legal representatives, the Corporation and its Affiliates,
their employees and shareholders. All expenses of administration of the Plan
shall be borne by the Corporation, including any reasonable brokerage fees
relating to the purchase of Shares under the Plan.

SECTION 4.        ELIGIBILITY

The Board shall, from time to time, prior to the commencement of a calendar year
(except for the 1999 calendar year), determine which Key Employees shall be
eligible to participate in the Plan for such year ("Eligible Key Employees").

SECTION 5.        ELECTION

An Eligible Key Employee may, with respect to any particular Performance Period,
elect to participate in the Plan. In order to elect to participate in the Plan
with respect to any particular Performance Period, an Eligible Key Employee
shall complete and deliver to the Corporation a written election before the last
business day of the calendar year immediately preceding the Performance Period.


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An Eligible Key Employee who elects to participate in the Plan with respect to a
particular Performance Period shall be entitled to elect on an irrevocable basis
to have either 50% or 100% of such Eligible Key Employee's potential Management
Incentive Compensation with respect to that Performance Period provided under
the Plan in the form of Bonus DSUs in lieu of payment under the Corporation's
Management Incentive Plan. With respect to the 1999 Performance Period only, an
Eligible Key Employee will be given 15 business days from the date the
Corporation receives an advance tax ruling from Revenue Canada that the Plan
will be a "prescribed plan or arrangement" under paragraph 6801(d) of the
regulations under the Income Tax Act (Canada) to make the elections described
above for such Performance Period.

SECTION 6.        GRANT OF AWARDS OF BONUS DSUs

Subject to confirmation by the Board, the Committee shall, from time to time,
choose from among Eligible Key Employees who shall have elected, under Section 5
hereof, to participate in the Plan, those to whom it recommends that Bonus DSUs
be awarded and determine, in accordance with Section 7 hereof, the number of
Bonus DSUs which it recommends be awarded to such Eligible Key Employees who
shall have elected to participate in the Plan for a particular Performance
Period. The Committee shall, subject to confirmation by the Board, recommend the
conversion date ("Conversion Date") of each award of Bonus DSUs under the Plan.
Each award of Bonus DSUs shall be confirmed by an instrument in writing issued
by the Corporation to the Participant.

A Participant who shall have been awarded Bonus DSUs under the Plan shall enter
into an Agreement with the Corporation, which shall comply and be consistent
with the terms of the Plan set out herein, with respect to such award of Bonus
DSUs, which Agreement shall be effective and dated as of the Conversion Date of
the award.

The Bonus DSUs shall be credited to the account of the Eligible Key Employee as
of the Conversion Date. The Bonus DSUs will be fully vested upon being credited
to an Eligible Key Employee.

The Participant's entitlement to payment of Bonus DSUs at the Termination Date
shall not be subject to satisfaction, following the Conversion Date, of any
requirements as to any minimum period of employment.

SECTION 6.1.      GRANT OF AWARDS OF DISCRETIONARY DSUs

Regardless of an Eligible Key Employee's election under Section 5, the Chief
Executive Officer of the Corporation, the Chairperson of the Committee or the
Committee may in his, her or its sole discretion (as applicable) grant, from
time to time, Discretionary DSUs to an Eligible Key Employee. With respect to
any potential award of Discretionary DSUs to the Chief Executive Officer of the
Corporation, such award (if any) shall be granted by the Chairperson of the
Committee or the Committee. The Committee, the Chairperson of the Committee or
the Chief Executive Officer of the Corporation, as applicable, shall determine
the date on which such Discretionary DSUs may be granted, which date shall in
any event precede the Eligible Key Employee's Termination Date. The Chief
Executive Officer of the Corporation, the Chairperson


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of the Committee or the Committee may in his, her or its sole discretion (as
applicable) attach time based vesting conditions (which shall be expressed as a
requisite number of months after the date of the grant of the Discretionary
DSUs) to any such grant of Discretionary DSUs which, subject to this Section
6.1, if not attained by the Eligible Key Employee prior to the date of
termination of employment from the Corporation or an Affiliate, as applicable,
shall result in the forfeiture of such non-vested Discretionary DSUs. Each award
of Discretionary DSUs, including any related time based vesting requirement,
shall be confirmed by an instrument in writing issued by the Corporation to the
Participant.

Except as provided in this Section 6.1, if the employment of a Participant is
terminated for any reason following the grant of Discretionary DSUs and prior to
fulfilment of the vesting conditions attached to such grant by the Chief
Executive Officer of the Corporation, the Chairperson of the Committee or the
Committee, as applicable, the Participant shall forfeit all rights, title and
interest with respect to such Discretionary DSUs including, for greater
certainty, any additional Discretionary DSUs granted pursuant to Section 8 in
respect of such Discretionary DSUs.

Notwithstanding any other provision of this Plan, all Discretionary DSUs
recorded in a Participant's account under the Plan, including for greater
certainty any additional Discretionary DSUs granted pursuant to Section 8 in
respect of such Discretionary DSUs, shall vest immediately and shall not be
considered forfeited under this Section 6.1 upon the earliest of the
Participant's death, a Change in Control, the Participant's Disability Date and
the termination of the Plan in accordance with Section 12.

SECTION 7.        COMPUTATION OF AWARDS OF BONUS DSUs

For the purpose of determining the number of Bonus DSUs to be awarded to an
Eligible Key Employee in accordance with Section 6 hereof, the Committee shall
compute the amount of Management Incentive Compensation that would have been
awarded to the Eligible Key Employee had such employee not elected to
participate in the Plan for the relevant Performance Period (the "Global Dollar
Amount"). The Committee shall then award a number of Bonus DSUs (including
fractional Bonus DSUs) to the Eligible Key Employee equal to the quotient
determined by dividing: (i) the product determined by multiplying (a) the
percentage amount elected by the Eligible Key Employee in accordance with
Section 5 hereof, and (b) the Global Dollar Amount, by (ii) the Market Value of
a Share determined on the Conversion Date. The Bonus DSUs shall be credited to
the account of the Eligible Key Employee as of the Conversion Date.

SECTION 8.        DIVIDEND-LIKE AMOUNTS

A Participant's account shall, from time to time during the term of the
Participant's Agreement(s), including the period following the Participant's
Termination Date and until the Entitlement Date referred to in Section 9 hereof,
be credited with additional Bonus DSUs and/or Discretionary DSUs, the number of
which shall be equal to the quotient determined by dividing one hundred percent
(100%) of the dividends declared and that would have been paid to the
Participant if the Bonus DSUs and/or Discretionary DSUs, as the case may be, in
his or her


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account on the relevant record date for dividends on the Shares had been Shares
(excluding stock dividends, but including dividends which may be paid in cash or
in shares at the option of the shareholder) by the Market Value of a Share on
the payment date of such dividends, with fractions computed to four decimal
places.

SECTION 9.        PAYMENT OF BONUS DSUs AND DISCRETIONARY DSUs

Subject to Section 9.1, a Participant or the legal representative of the
Participant's estate, as applicable, may elect the date as of which the value of
the Bonus DSUs and vested Discretionary DSUs credited to the Participant's
account, as may be adjusted pursuant to Section 19 hereof, shall be determined
and payable (the "Entitlement Date") by filing an irrevocable election with the
Corporation no later than November 30 of the calendar year commencing
immediately after the Participant's Termination Date. The Entitlement Date
elected by a Participant or the legal representative of the Participant's
estate, as applicable, pursuant to this Section 9 shall not be before the later
of 15 days after the date on which the election is filed with the Corporation
and 30 days after the Participant's Termination Date and shall not be later than
December 15 of the calendar year commencing immediately after the Participant's
Termination Date. Where a Participant or the legal representative of the
Participant's estate, as applicable, does not elect a particular date within the
permissible period set out above as his Entitlement Date, the Entitlement Date
for such Participant shall be December 15 of the calendar year commencing
immediately after the Participant's Termination Date. The value, determined as
at the Entitlement Date, of the Bonus DSUs and vested Discretionary DSUs
redeemed by or in respect of a Participant shall, after deduction of any
applicable taxes and other source deductions required to be withheld by the
Corporation, be used to purchase on behalf of the Participant or the
Participant's estate, as applicable, Shares on the open market in accordance
with the provisions of this Section 9.

Prior to 11:00 a.m. on the Entitlement Date or, where the Entitlement Date is
not a trading day for Shares on the stock exchange which is relevant for
determining the value of the Bonus DSUs and vested Discretionary DSUs, on the
next such trading day, the Corporation shall notify the Broker as to the number
of whole Shares to be purchased by the Broker on behalf of the Participant or
the Participant's estate, as applicable, on the open market, by dividing the
cash value of the redeemed Bonus DSUs and vested Discretionary DSUs after
deduction of applicable taxes and other source deductions as provided in this
Section 9, by the Market Value of a Share as determined on the Entitlement Date.
As soon as practicable thereafter, the Broker shall purchase on the open market
the number of Shares which the Corporation has requested the Broker to purchase
and notify the Participant, or the Participant's estate, as applicable, and the
Corporation of: a) the aggregate purchase price ("Aggregate Purchase Price") of
the Shares, b) the purchase price per Share or, if the Shares were purchased at
different prices, the average purchase price (computed on a weighted average
basis) per Share ("Price per Share"), c) the amount of any related reasonable
brokerage commission, and d) the settlement date for the purchase of the Shares.
On the settlement date, upon payment of the Aggregate Purchase Price and related
reasonable brokerage commission by the Corporation, acting as an agent for the
Participant or the Participant's estate, on or before the settlement date, the
Broker shall deliver to


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the Participant or to his representative a certificate representing the Shares
purchased on behalf of the Participant or the Participant's estate, as
applicable.

If, after the Broker applies the value of a Participant's Bonus DSUs and vested
Discretionary DSUs, net of applicable withholdings, to the purchase of whole
Shares as provided for herein, an amount remains payable under the Plan to the
Participant or his or her estate, as applicable, such amount shall be paid in
cash.

The Corporation shall have the right, in its sole discretion, to pay (or cause
the Participant's employer to pay) entirely in cash the value, as computed under
the Plan, of the Bonus DSUs and vested Discretionary DSUs entitlement (less any
applicable withholdings) of the Participant or the Participant's estate, as
applicable, should it deem the regulatory or other requirements of the
applicable jurisdiction associated with the purchase of, or payment in, Shares
too onerous to it or to the Participant, the Participant's estate or the
Participant's employer or if for any other reason it is in the best interest of
the Corporation to make or require such payment in cash.

SECTION 9.1       LIMITATIONS ON ELECTION OF ENTITLEMENT DATE

In the event that a Participant's Termination Date shall occur within ninety
(90) days following a Change in Control of the Corporation, then,
notwithstanding Section 9, the Entitlement Date shall be the fifth trading day
following the Participant's Termination Date. If the Entitlement Date would
otherwise fall between the record date for a dividend on the Shares and the
related dividend payment date then notwithstanding Section 9, the Entitlement
Date shall be the day immediately following the date of payment of such dividend
for purposes of recording in the account of the Participant amounts referred to
in Section 8 hereof and making the calculation of the value of Bonus DSUs and
vested Discretionary DSUs contemplated by Section 9. In the event that the
Corporation is unable, by a Participant's Entitlement Date, to compute the final
number of Bonus DSUs and vested Discretionary DSUs credited to such
Participant's account by reason of the fact that any data required in order to
compute the Market Value of a Share has not been made available to the
Corporation, then the Entitlement Date shall be the next following trading day
on which such data is made available to the Corporation.

In any event and notwithstanding any other provision of the Plan, all amounts
payable to, or in respect of, an Eligible Key Employee hereunder shall be paid
on or before December 31 of the year commencing immediately after the year in
which the Eligible Key Employee's Termination Date occurred.

SECTION 10.       PARTICIPANT'S ACCOUNT

The Corporation shall maintain in its books an account for each Participant
recording at all times the number of Bonus DSUs and Discretionary DSUs standing
to the credit of the Participant. Upon payment in satisfaction of Bonus DSUs and
Discretionary DSUs credited to a Participant in the manner described herein or
upon forfeiture of Discretionary DSUs as provided in Section 6.1, such Bonus
DSUs or Discretionary DSUs, as applicable, shall be cancelled. A written
confirmation of the balance in a Participant's account hereunder shall be mailed
by the Corporation to the Participant at least annually.


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SECTION 11.       EFFECTIVE DATE OF THE PLAN

The effective date of the Plan shall be April 1, 1999.

SECTION 12.       AMENDMENTS TO, SUSPENSION OR TERMINATION OF, THE PLAN

The Board may from time to time amend, suspend or terminate the Plan in whole or
in part. However, any such amendment, suspension or termination shall not
adversely affect the rights accrued to any Participant under any Agreement
existing at the time of such amendment, suspension or termination without the
consent of the affected Participant. Notwithstanding the foregoing, any
amendment or termination of the Plan shall be such that the Plan continuously
meets the requirements of paragraph 6801(d) of the Income Tax Regulations or any
successor provision thereto.

If the Board terminates the Plan, prior awards of Bonus DSUs and Discretionary
DSUs (if any) shall remain outstanding and in effect and paid in due course upon
the Participant's Termination Date for purposes of the Plan in accordance with
the applicable terms and conditions applicable to such Bonus DSUs and
Discretionary DSUs, as applicable, immediately prior to the termination of the
Plan.

SECTION 13.       PURCHASES ON THE OPEN MARKET

Purchases of Shares pursuant to the Plan shall be made on the open market by a
broker independent from the Corporation designated by the Participant and who is
a member of The Toronto Stock Exchange or, where the Shares are not listed on
The Toronto Stock Exchange, the stock exchange which is relevant for determining
the value of the Bonus DSUs and Discretionary DSUs ("Broker"). Any such
designation may be changed from time to time. Upon designation of a Broker or at
any time thereafter, the Corporation may elect to provide the designated Broker
with a letter agreement to be executed by the Broker and entered into with the
Participant and to which the Corporation would also be a party, setting forth,
inter alia, (i) the Broker's concurrence to being so designated, to act for the
Participant's account in accordance with customary usage of the trade with a
view to obtaining the best share price for the Participant, and to delivering to
the Participant or his/her representative the share certificate for the Shares
purchased upon payment by the Corporation of the purchase price and related
reasonable brokerage commission, and (ii) the Corporation's agreement to notify
the Broker of the number of Shares to be purchased and to pay the purchase price
and the related reasonable brokerage commission, provided however that no terms
of said letter agreement shall have the effect of making the Broker or deeming
the Broker to be an affiliate of (or not independent from) the Corporation for
purposes of any applicable corporate, securities or stock exchange requirement.

SECTION 14.       RIGHTS OF PARTICIPANTS

Except as specifically set out in the Plan or an Agreement, no Eligible Key
Employee, Participant or other person shall have any claim or right to any
Shares or other benefit in respect of Bonus DSUs or Discretionary DSUs granted
pursuant to the Plan.


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Neither the Plan nor any award thereunder shall be construed as granting a
Participant a right to be retained as an employee of the Corporation or of any
of its Affiliates or a claim or right to any future grants of Bonus DSUs or
Discretionary DSUs. Neither the Plan nor any action taken thereunder shall
interfere with the right of the employer of an Eligible Key Employee or a
Participant to terminate the employment of such Eligible Key Employee or
Participant at any time. For greater certainty, the payment of any sum of money
in cash in lieu of notice of the termination of employment shall not be
considered as extending the period of employment for the purposes of the Plan.

Under no circumstances shall Bonus DSUs or Discretionary DSUs be considered
Shares nor shall they entitle any Participant to exercise voting rights or any
other rights attaching to the ownership of Shares, nor shall any Participant be
considered the owner of Shares by virtue of this Plan until after the date of
the purchase of such Shares on the open market pursuant to Section 9 hereof.

SECTION 15.       DEATH OF PARTICIPANT

In the event of a Participant's death, any and all Bonus DSUs and Discretionary
DSUs then credited to the Participant's account shall become payable to the
Participant's estate in accordance with Section 9 hereof.

SECTION 16.       COMPLIANCE WITH APPLICABLE LAWS

Any obligation of the Corporation with respect to its Shares pursuant to the
terms of the Plan is subject to compliance with all applicable laws. Should the
Corporation, in its sole discretion, determine that it is not feasible or
practicable to make payment of a Discretionary DSU or a Bonus DSU through the
purchase of Shares on the open market by reason of any such laws, such
obligation shall be satisfied by means of an equivalent cash payment. The
Participant shall comply with all such laws and furnish the Corporation with any
and all information and undertakings as may be required to ensure compliance
therewith.

SECTION 17.       WITHHOLDING TAXES

The Corporation shall be entitled to deduct any amount of withholding taxes and
other withholdings from any amount paid or credited hereunder.

SECTION 18.       TRANSFERABILITY

In no event may the rights or interests of a Participant under the Plan be
assigned, encumbered, pledged, transferred or alienated in any way, except to
the extent that certain rights may pass to a beneficiary or legal representative
upon death of a Participant, by will or by the laws of succession and
distribution.

SECTION 19.       ALTERATION OF NUMBER OF DSUS SUBJECT TO THE PLAN

In the event of any stock dividend, stock split or consolidation affecting the
number of Shares, the Bonus DSUs and the Discretionary DSUs credited to a
Participant's


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account under the Plan will be adjusted in the same manner as if each Bonus DSU
and each Discretionary DSU were a Share. In the event of any exchange of shares
or other change in the Shares into a different number or kind of shares of the
Corporation or of any corporation related thereto, or of any other change in the
Shares or shares into which Shares have been changed or for which they have been
exchanged, such equitable adjustments, as the Committee may reasonably
determine, shall be made with respect to the number of Bonus DSUs and
Discretionary DSUs then recorded in the Participant's account under the Plan.
However, no amount will be paid to, or in respect of, a Participant under the
Plan or pursuant to any other arrangement, and no Bonus DSU or Discretionary DSU
will be granted nor will any credit be made to such Participant's account under
the Plan to compensate for a downward fluctuation in the price of Shares, nor
would any other form of benefit be conferred upon, or in respect of a
Participant for such purpose.

SECTION 20.       GOVERNING LAW

The Plan shall be governed by and interpreted in accordance with the laws in
force in the Province of Alberta.