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                                                                     EXHIBIT 4.8


                                                                  MARCH 29, 1999


             THE NOVA CHEMICALS CORPORATION DEFERRED SHARE UNIT PLAN
                           FOR NON-EMPLOYEE DIRECTORS


SECTION 1.        PURPOSE

The purpose of the NOVA Chemicals Corporation Deferred Share Unit Plan for
Non-Employee Directors is to significantly strengthen the link between Director
and shareholder interests by encouraging Directors to 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 8
     hereof;

(c)  "Agreement" means the agreement as it may be amended from time to time,
     entered into by the Corporation and a Director pursuant to Section 5 hereof
     in connection with the grant of DSUs hereunder to said Director and setting
     forth the related rights and obligations of the Corporation and of the
     Director;

(d)  "Attendance Fees" means fees paid to a Director by the Corporation as
     remuneration for services performed as a Director during a Quarter,
     including fees for attending meetings and fees for time spent travelling
     but excluding a Director's Retainer Fees from the Corporation, which become
     payable at the end of a Quarter in respect of services rendered during the
     Quarter;

(e)  "Attendance Dollar Amount" has the meaning assigned thereto in Section 6
     hereof;

(f)  "Board" means the Board of Directors of NOVA Chemicals Corporation;

(g)  "Broker" has the meaning assigned thereto in Section 12 hereof;

(h)  "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 Corporation Act), or a group of persons, are in a
     position to exercise effective control of the Corporation;

(i)  "Committee" means the committee of directors of the Corporation generally
     responsible for compensation related matters and which is currently named
     the Human Resources Committee;


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(j)  "Conversion Date" means, with respect to any Quarter, the date used to
     determine the Market Value of a Share for purposes of determining the
     number of DSUs to be credited in respect of that Quarter to a Director's
     account; which date shall be the date recommended by the Committee and
     confirmed by the Board and which shall generally be the last day of each
     Quarter and, in any event, shall not be earlier than the first business
     day, or later than December 31, of the calendar year immediately following
     the year in which the Director made the election in respect of which the
     DSUs are being granted;

(k)  "Corporation" means NOVA Chemicals Corporation;

(l)  "Deferred Share Unit", or "DSU", means a unit credited by means of a
     bookkeeping entry on the books of the Corporation to a Participant's
     account 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 one
     Share;

(m)  "Director" means each member of the Board who is not otherwise an employee
     of the Corporation or of an Affiliate of the Corporation;

(n)  "Entitlement Date" has the meaning assigned thereto in Section 8 hereof;

(o)  "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 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;

(p)  "Participant" means a Director who has been granted DSUs under the Plan;

(q)  "Plan" means the NOVA Chemicals Corporation Deferred Share Unit Plan for
     Non-Employee Directors as amended from time to time;

(r)  "Quarter" means a fiscal quarter of the Corporation which is used for
     accounting purposes and which, until changed by the Board, shall be the
     three month period ending March 31, June 30, September 30 or December 31 in
     any calendar year;

(s)  "Retainer Dollar Amount" has the meaning assigned thereto in Section 6
     hereof;

(t)  "Retainer Fees" means such portion of a Director's annual retainer fees as
     determined by the Corporation, 25% of which become payable at the end of
     each Quarter;

(u)  "Share" means a common share, without nominal or par value, of the
     Corporation; and


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(v)  "Termination Date" shall mean the earliest date on which both the following
     conditions are met: the Director (1) has ceased to be a Director as defined
     above for any reason whatsoever, including the death of the Director, and
     (2) is neither an employee of the Corporation or an Affiliate nor a member
     of the board of an Affiliate.

SECTION 3.        ADMINISTRATION OF THE PLAN

Subject to Sections 4, 8 and 11 hereof, the Plan shall be administered by the
Committee, beginning with the 1999 calendar year, 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, its 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.        ELECTION

A Director may, with respect to any particular calendar year, elect to
participate in the Plan. In order to elect to participate in the Plan with
respect to any particular calendar year, a Director shall complete and deliver
to the Corporation a written election on or before the last business day of the
calendar year ending immediately before the calendar year in which DSUs may be
granted to such Director under Section 5 hereof in respect of such election.

A Director who elects to participate in the Plan with respect to a particular
calendar year shall be entitled to elect in lieu of cash payment of Retainer
Fees or Attendance Fees on an irrevocable basis to have either fifty percent
(50%) or one hundred percent (100%) of the value of the Retainer Fees and either
fifty percent (50%) or one hundred percent (100%) of the Attendance Fees that
may be paid to such Director with respect to that calendar year provided under
the Plan in the form of DSUs. With respect to the 1999 calendar year only, an
eligible Director will be given 15 business days from the date the Corporation
receives an advanced 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
calendar year.

SECTION 5.        GRANT OF DSUs

Prior to the commencement of a calendar year (except for the 1999 calendar
year), the Board will determine the portion of the Directors' Retainer Fees for
such year that will be paid in Shares.

The Committee shall, subject to confirmation by the Board, recommend the
Conversion Date of each grant of DSUs under the Plan.

Each grant of DSUs shall be confirmed by an instrument in writing issued by the
Corporation to the Participant.


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A Participant who shall have been granted 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 grant of DSUs, which
Agreement shall be effective and dated as of the Conversion Date of the grant.

The DSUs shall be credited to the account of the Participant as of the
Conversion Date. The DSUs will be fully vested upon being credited to a
Participant.

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

SECTION 6.        COMPUTATION OF DSUs

In order to compute the number of DSUs to be granted to a Director under Section
5 hereof with respect to a Quarter in a calendar year for which a Director made
an election under Section 4 hereof in respect of Retainer Fees, the Committee
shall first determine an amount expressed in dollars ("Retainer Dollar Amount")
which shall be assigned to such Director based on the amount of Retainer Fees
payable to such Director for such Quarter and the Director's election pursuant
to Section 4 hereof. The number of DSUs (including fractional DSUs) to be
granted to a Director under the Plan and credited to his or her account in
respect of Retainer Fees for any particular Quarter shall be equal to the
quotient determined by dividing: (i) the product determined by multiplying (a)
the percentage amount elected by the Director in accordance with Section 4
hereof, and (b) the Retainer Dollar Amount by, (ii) the Market Value of a Share
on the relevant Conversion Date.

In order to compute the number of DSUs to be granted to a Director under Section
5 hereof with respect to a Quarter in a calendar year for which a Director made
an election under Section 4 hereof in respect of Attendance Fees, the Committee
shall first determine an amount expressed in dollars ("Attendance Dollar
Amount") which shall be assigned to such Director based on the amount of
Attendance Fees payable to such Director for such Quarter and the Director's
election pursuant to Section 4 hereof. The number of DSUs (including fractional
DSUs) to be granted to a Director under the Plan and credited to his or her
account in respect of Attendance Fees for any particular Quarter shall be equal
to the quotient determined by dividing: (i) the product determined by
multiplying (a) the percentage amount elected by the Director in accordance with
Section 4 hereof, and (b) the Attendance Dollar Amount by, (ii) the Market Value
of a Share on the relevant Conversion Date.

SECTION 7.        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 8 hereof,
be credited with additional DSUs, the number of which shall be equal to the
quotient determined by dividing one hundred percent (100%) of the dividends
declared that would have been paid to the Participant if the DSUs in his or her
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


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shareholder), by the Market Value of a Share on the payment date of such
dividend, with fractions computed to four decimal places.

SECTION 8.        PAYMENT OF DSUs

On the date which is 30 days after a Participant's Termination Date (the
"Entitlement Date") the DSUs credited to the Participant's account, as may be
adjusted pursuant to Section 18 hereof, shall be redeemable by and be payable to
the Participant or the Participant's estate, as applicable. The value of the
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 8.

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 the foregoing provisions of this Section 8, the Entitlement Date
shall be the fifth (5th) 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 the foregoing provisions of this Section 8, 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 7 hereof and making the calculation of DSUs contemplated by this Section
8. In the event that the Corporation is unable, by a Participant's Entitlement
Date, to compute the final number of 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, a Participant hereunder shall be paid on or before
December 31 of the year commencing immediately following the year in which the
Participant's Termination Date occurred.

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 DSUs, 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 DSUs after
deduction of applicable taxes and other source deductions as provided in this
Section 8, 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, (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 agent for the


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Participant or the Participant's estate, on or before the settlement date, the
Broker shall deliver to the Participant or to his representative a certificate
representing the Shares.

If, after the Broker applies the value of a Participant's 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 entirely in
cash the value, as computed under the Plan, of the DSU 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 such payment in cash.

SECTION 9.        PARTICIPANT'S ACCOUNT

The Corporation shall maintain in its books an account for each Participant
recording at all times the number of DSUs standing to the credit of the
Participant. Upon payment in satisfaction of DSUs credited to a Participant in
the manner described herein, such DSUs 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.

SECTION 10.       EFFECTIVE DATE OF THE PLAN

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

SECTION 11.       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.

If the Board terminates the Plan, prior grants of DSUs shall, at the discretion
of the Board, either (a) become immediately payable in accordance with the terms
of the Plan in effect at such time, or (b) 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
DSUs immediately prior to the termination of the Plan.

SECTION 12.       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 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


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designated, to act for the Participants 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.


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SECTION 13.       RIGHTS OF PARTICIPANTS

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

Neither the Plan nor any grant thereunder shall be construed as granting a
Participant a right to be retained as a Director of the Corporation or a claim
or right to any future grants of DSUs.

Under no circumstances shall 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 as referred to herein.

SECTION 14.       DEATH OF PARTICIPANT

In the event of a Participant's death, any and all DSUs then credited to the
Participant's account shall become payable to the Participant's estate in
accordance with Section 8 hereof.

SECTION 15.       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 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 16.       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 17.       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 18.       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 DSUs credited to a Participant's account under the Plan
will be adjusted in the same manner as if each 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


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reasonably determine, shall be made with respect to the number of 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 DSU will be granted nor will any credit be made to such
Participant's DSU 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 19.       GOVERNING LAW

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