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                                                                   EXHIBIT 4.02
                       UNITED STATES FILTER CORPORATION

                       1991 EMPLOYEE STOCK OPTION PLAN


     1.   Purpose. The United States Filter Corporation 1991 Employee Stock
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Option Plan (the "Plan") is hereby established to grant to officers, directors
and key employees of United States Filter Corporation and its Subsidiaries
(individually and collectively, the "Company") a favorable opportunity to
acquire Common Stock of United States Filter Corporation (the "Stock"), and to
create an incentive for such persons to remain in the employ of the Company and
to contribute to its success.

     As used in the Plan, the term "Code" shall mean the Internal Revenue Code
of 1986, as amended, and any successor statute, and the terms "Parent" and
"Subsidiary" shall have the meaning set forth in Sections 424(e) and (f) of the
Code.

     2.   Administration.  The Plan shall be administered by the Compensation
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Committee of the Board of Directors of the Company (the "Committee"). The
Committee shall determine the meaning and application of the provisions of the
Plan and all option agreements executed pursuant thereto, and its decisions
shall be conclusive and binding upon all interested persons. The Committee may
not grant an option to any member of the Committee. An option may be granted to
a member of the Committee only by action of the Board of Directors of the
Company. Subject to the provisions of the Plan, the Committee shall have the
sole authority to determine:

          (a) The persons to whom options to purchase Stock shall be granted;
                                                                              
          (b) The number of options to be granted to each person;             
          
          (c) The price to be paid for the Stock upon the exercise of each
              option;
         
          (d) The period within which each option shall be exercised; and     
                                                                              
          (e) The terms and conditions of each stock option agreement entered
              into between the Company and persons to whom the Company has
              granted an option.

     3.   Eligibility. Officers, directors and key employees of the Company, as
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determined by the Committee, shall be eligible to receive grants of options
under the Plan. No individual may be granted, in any calendar year, options
under the Plan to purchase more than 150,000 shares of Common Stock.

     4.   Stock Subject to Plan.  There shall be reserved for issue upon the
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exercise of options granted under the Plan 6,131,250 shares of Common Stock or
the number of shares of Stock, which, in accordance with the provisions of
Section 9 hereof, shall be substituted therefor. Such shares may be authorized
but unissued shares or treasury shares. If an option granted under the

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/1/  As amended by the Board of Directors through June 12, 1997.

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Plan shall expire or terminate for any reason without having been exercised in
full, unpurchased shares subject thereto shall again be available for the
purposes of the Plan.

     5.   Terms of Options.
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          (a)  Incentive Stock Options. It is intended that options granted
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pursuant to this Section 5(a) qualify as incentive stock options as defined in
Section 422 of the Code. Incentive stock options shall be granted only to
employees of the Company. Each stock option agreement evidencing an incentive
stock option shall provide that the option is subject to the following terms and
conditions and to such other terms and conditions not inconsistent therewith as
the Committee may deem appropriate in each case:

               (1)  Option Price. The price to be paid for each share of Stock
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upon the exercise of each incentive stock option shall be determined by the
Committee at the time the option is granted, but shall in no event be less than
100% of the fair market value of the shares on the date the option is granted,
or not less than 110% of the fair market value of such shares on the date such
option is granted in the case of an individual then owning (within the meaning
of Section 424(d) of the Code) more than 10% of the total combined voting power
of all classes of stock of the Company or of its Parent or Subsidiaries. As used
in this Plan the term "date the option is granted" means the date on which the
Committee authorizes the grant of an option hereunder or any later date
specified by the Committee. Fair market value of the shares shall be (i) the
mean of the high and low prices of shares of Stock sold on a national stock
exchange on the date the option is granted (or if there was no sale on such
date, the highest asked price for the Stock on such date), or (ii) if the Stock
is not listed on any national stock exchange on the date the option is granted,
the mean between the "bid" and "asked" prices of the Stock in the National Over-
The-Counter Market on the date the option is granted, or (iii) if the Stock is
not traded in any market, that price determined by the Committee to be fair
market value, based upon such evidence as it may think necessary or desirable.

               (2)  Period of Option. The period or periods within which an
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option may be exercised shall be determined by the Committee at the time the
option is granted, but in no event shall any option granted hereunder be
exercised more than ten years from the date the option was granted, nor more
than five years from the date the option was granted in the case of an
individual then owning (within the meaning of Section 424(d) of the Code) more
than 10% of the total combined voting power of all classes of stock of the
Company or of its Parent or Subsidiaries.

               (3)  Payment for Stock. The option exercise price for each share
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of Stock purchased under an option shall be paid in full at the time of
purchase. The Committee may provide that the option price be payable, at the
election of the holder of the option and with the consent of the Committee, in
whole or in part either in cash or by delivery in transferable form of shares of
Stock which have been held by the Optionee for at least six months prior to the
date of exercise or such shorter period as qualifies as the measurement period
for "mature shares" under applicable generally accepted accounting rules. Such
delivered shares of Stock shall be valued for such purpose at their fair market
value on the date on which the option is exercised. In the discretion of the
Committee, the delivery of shares of Stock in full or partial payment of the
option exercise price may be accomplished without the actual delivery by the
Optionee of stock certificates representing the delivered shares under a
procedure whereby the Optionee attests in

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writing, on a form acceptable to the Committee, to ownership of the subject
shares and the Company delivers to the Optionee certificates representing the
net shares issuable upon such option exercise. Payment may also be made, in the
discretion of the Committee, by delivery (including by fax) to the Company or
its designated agent of an executed irrevocable option exercise form together
with irrevocable instructions to a broker-dealer to sell or margin a sufficient
portion of the shares and deliver the sale or margin loan proceeds directly to
the Company to pay for the exercise price. No share of Stock shall be issued
until full payment therefor has been made, and no employee shall have any rights
as an owner of Stock until the date of issuance to him of the stock certificate
evidencing such Stock.

               (4)  Limitation on Amount. Subject to the overall limitations of
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Section 4 hereof (relating to the aggregate shares subject to the Plan), the
aggregate fair market value (determined as of the time the option is granted) of
the Common Stock with respect to which incentive stock options are exercisable
for the first time by the Optionee during any calendar year (under the Plan and
all other incentive stock option plans of the Company, any Parent or
Subsidiaries) shall not exceed $100,000.

          (b)  Nonqualified Stock Options. Each nonqualified stock option
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granted under the Plan shall be evidenced by a stock option agreement between
the person to whom such option is granted and the Company. Such stock option
agreement shall provide that the option is subject to the following terms and
conditions and to such other terms and conditions not inconsistent therewith as
the Committee may deem appropriate in each case:

               (1)  Option Exercise Price. The exercise price to be paid for
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each share of Stock upon the exercise of an option shall be determined by the
Committee at the time the option is granted, but shall in no event be less than
100% of the fair market value of the shares on the date the option is granted.
As used in this Plan, the term "date the option is granted" means the date on
which the Committee authorizes the grant of an option hereunder or any later
date specified by the Committee. Fair market value of the shares shall be (i)
the mean of the high and the low prices of shares of Stock sold on a national
stock exchange on the date the option is granted (or if there was no sale on
such date, the highest asked price for the Stock on such date), or (ii) if the
Stock is not listed on a national stock exchange on the date the option is
granted the mean between the "bid" and "asked" prices of the Stock in the
National Over-The-Counter market on the date the option is granted, or (iii) if
the Stock is not traded in any market, that price determined by the Committee to
be fair market value, based upon such evidence as it may think necessary or
desirable.

               (2)  Period of Option. The period or periods within which an
                    ----------------
option may be exercised shall be determined by the Committee at the time the
option is granted, but shall in no event exceed ten years from the date the
option is granted.

               (3)  Payment for Stock. The option exercise price for each share
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of Stock purchased under an option shall be paid in full at the time of
purchase. The Committee may provide that the option price be payable, at the
election of the holder of the option and with the consent of the Committee, in
whole or in part either in cash or by delivery in transferable form of shares of
Stock which have been held by the Optionee for at least six months prior to the
date of exercise or such shorter period as qualifies as the measurement period
for "mature shares" under applicable generally accepted accounting rules. Such
delivered shares of Stock shall be valued for

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such purpose at their fair market value on the date on which the option is
exercised. In the discretion of the Committee, the delivery of shares of Stock
in full or partial payment of the option exercise price may be accomplished
without the actual delivery by the Optionee of stock certificates representing
the delivered shares under a procedure whereby the Optionee attests in writing,
on a form acceptable to the Committee, to ownership of the subject shares and
the Company delivers to the Optionee certificates representing the net shares
issuable upon such option exercise. Payment may also be made, in the discretion
of the Committee, by delivery (including by fax) to the Company or its
designated agent of an executed irrevocable option exercise form together with
irrevocable instructions to a broker-dealer to sell or margin a sufficient
portion of the shares and deliver the sale or margin loan proceeds directly to
the Company to pay for the exercise price. No share of Stock shall be issued
until full payment therefor has been made, and no employee shall have any rights
as an owner of Stock until the date of issuance to him of the stock certificate
evidencing such Stock.

     6.   Nontransferability.  The options granted pursuant to the Plan shall be
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nontransferable except by will or the laws of descent and distribution, and
shall be exercisable during the optionee's lifetime only by him and after his
death, by his personal representative or by the person entitled thereto under
his will or the laws of intestate succession.

     7.   Termination of Employment. Upon termination of the optionee's
          -------------------------  
employment, except as the Committee shall otherwise authorize at the time of
grant and any time thereafter, his rights to exercise options then held by him
shall be only as follows:

          (a)  Death or Disability. Upon the death of any person holding options
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granted under this Plan, his options shall be exercisable, by the holder's
representative or by the person entitled thereto under his will or the laws of
intestate succession, only if and to the extent they are exercisable on the date
of his death, and such options shall terminate twelve months after the date of
his death (or such shorter period as the Committee may prescribe in his option
agreement). Upon the disability of an optionee his options shall be exercisable
only if and to the extent they are exercisable on the date of his disability,
and such options shall terminate twelve months after the date of his disability
(or such shorter period as the Committee may prescribe in his option agreement).
Notwithstanding the foregoing, with respect to options granted on or after June
12, 1997, if, upon the disability of an optionee, the optionee's age plus years
of continuous service with the Company and its affiliates and predecessors (as
combined and rounded to the nearest month) equal 65 or more, then all of his
options shall be exercisable, whether or not they were exercisable on the date
of such disability, for the exercise period stated above. However, in no event
shall any option be exercised more than ten years from the date the option was
granted. For purposes of this Section 7(a), an individual is disabled if he is
unable to engage in any substantial gainful activity by reason of any medically
determinable physical or mental impairment which can be expected to result in
death or which has lasted or can be expected to last for a continuous period of
not less than 12 months.

          (b)  Retirement. Upon the retirement of an officer, director or
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employee or the cessation of services provided by a nonemployee (either pursuant
to a Company retirement plan, if any, or pursuant to the approval of the
Committee) or if any officer, director, employee or non-employee optionee leaves
the Company, a Parent or a Subsidiary, for any reason other than as set forth in
Section 7(a), 7(c) or 7(d) hereof, his options shall be exercisable only if and
to the extent 

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they are exercisable on the date of his retirement or cessation of services and
such options shall terminate three months after the date of his retirement or
cessation of services as the case may be (or such shorter period as the
Committee may prescribe in his option agreement). The optionee's option shall
terminate upon the expiration of such period unless the holder of the options
dies prior thereto, in which event he shall be deemed to have died on the date
of his retirement or cessation of services. Notwithstanding the foregoing, with
respect to options granted on or after June 12, 1997 , if, upon the retirement
of an optionee, the optionee's age plus years of continuous service with the
Company and its affiliates [and predecessors] (as combined and rounded to the
nearest month) equal 65 or more, then all of his options shall be exercisable,
whether or not they were exercisable on the date of such retirement, for the
exercise period stated above. However, in no event shall such options be
exercised more than ten years from the date they are granted.

          (c)  Transfer to Related Corporation.  In the event that an officer, 
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director or employee leaves the employ of the Company to become an officer,
director or employee of any Subsidiary, or an officer, director or employee
ceases to serve as an officer or director or leaves the employ of a Subsidiary
to become an officer, director or employee of the Company or another Subsidiary,
such officer, director or employee shall be deemed to continue as an officer,
director or employee for all purposes of this Plan.

          (d)  Other Termination.  In the event an officer, director or 
               -----------------
employee ceases to serve as an officer or director or leaves the employ of the
Company, a Parent or a Subsidiary, or a nonemployee ceases to provide services
to the Company, of his own volition, or if his relationship with the Company, a
Parent or a Subsidiary is terminated by the Company for cause, his options shall
terminate at the earlier of the date his employment terminates or he ceases
providing services to the Company, a Parent or a Subsidiary, or the date he
receives written notice that his employment or rendering of services is or will
be terminated.

     8.   Acceleration upon Termination or Sale of Company.  The Committee may
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determine to accelerate the exercisability of any or all options after
termination of employment.  In the event the Parent or its stockholders enter
into an agreement to dispose of all or substantially all of the assets or
capital stock of the Parent by means of a sale, merger, consolidation,
reorganization, liquidation or otherwise, an option granted under the Plan will,
in the discretion of the Committee, if so authorized by the Board of Directors
and conditioned upon consummation of such disposition of assets or stock, become
immediately exercisable during the period commencing as of the date of the
execution of such agreement and ending as of the earlier of the stated
termination date of the option or the date on which the disposition of assets or
stock contemplated by the agreement is consummated.

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     9.   Adjustment of Shares.
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          (a)  In the event of changes in the outstanding Stock by reason of
stock dividends, stock splits, reverse stock splits, split-ups, consolidations,
recapitalizations, reorganizations or like events (as determined by the
Committee), an appropriate adjustment shall be made by the Committee in the
number of shares reserved under the Plan, in the number of shares set forth in
Section 4 hereof, and in the number of shares and the option price per share
specified in any stock option agreement with respect to any unpurchased shares.
The determination of the Committee as to what adjustments shall be made shall be
conclusive. Adjustments for any options to purchase fractional shares shall also
be determined by the Committee. The Committee shall give prompt notice to all
optionees of any adjustment pursuant to this Section.


          (b)  Section 9(a) above to the contrary notwithstanding, in the event
of any merger, consolidation or other reorganization of United States Filter
Corporation in which United States Filter Corporation is not the surviving or
continuing corporation (as determined by the Committee) or in the event of the
liquidation or dissolution of United States Filter Corporation, all options
granted hereunder shall terminate on the effective date of the merger,
consolidation, reorganization, liquidation, or dissolution unless the agreement
with respect thereto provides for the assumption of such options by the
continuing or surviving corporation. Any other provision of this Plan to the
contrary notwithstanding, all outstanding options granted hereunder shall be
fully exercisable for a period of 30 days prior to the effective date of any
such merger, consolidation, reorganization, liquidation, or dissolution unless
such options are assumed by the continuing or surviving corporation.

     10.  Securities Law Requirements.  The Committee may require prospective
          ---------------------------                                        
optionees, as a condition of either the grant or the exercise of an option, to
represent and establish to the satisfaction of the Committee that all shares of
Stock acquired upon the exercise of such option will be acquired for investment
and not for resale.  The Company may refuse to permit the sale or other
disposition of any shares acquired pursuant to any such representation until it
is satisfied that such sale or other disposition would not be in contravention
of applicable state or federal securities law.

     11.  Tax Withholding.  The Company may require an optionee to pay to the
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Company all applicable federal, state and local taxes which the Company is
required to withhold with respect to the exercise of an option granted
hereunder.

     12.  Amendment.  The Board of Directors may amend the Plan at any time, 
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except that without shareholder approval:

          (a)  The number of shares of Stock which may be reserved for issuance
under the Plan shall not be increased except as provided in Section 9 hereof;

          (b)  The option price per share of Stock may not be fixed at less than
100% of the fair market value of a share of Stock on the date the option was
granted;

          (c)  The maximum period of ten years during which the options may be
exercised may not be extended;

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          (d)  The class of persons eligible to receive options under the Plan
as set forth in Section 3 shall not be changed; and

          (e)  This Section 12 may not be amended in a manner that limits or
reduces the amendments which require shareholder approval.

     13.  Termination.  The Plan shall terminate automatically on February 27,
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2001.  The Board of Directors may terminate the Plan at any earlier time.  The
termination of the Plan shall not affect the validity of any option agreement
outstanding at the date of such termination, but no option shall be granted
after such date.

     14.  Effective Date.  The Plan shall be effective upon its adoption by the
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Board of Directors of the Company.  Options may be granted but not exercised
prior to stockholder approval of the Plan.  If any options are so granted and
stockholder approval shall not have been obtained on or before February 27,
1992, such options shall terminate retroactively as of the date they were
granted.

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