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                                                                   Exhibit 10.48


                           U. S. PLASTIC LUMBER CORP.
                   CERTIFICATE OF DESIGNATION OF PREFERENCES,
                           RIGHTS, AND LIMITATIONS OF
                      SERIES D PREFERRED STOCK, 15% COUPON

                  U.S. Plastic Lumber Corp., a corporation organized and
existing, under the laws of the State of Nevada (the "Corporation"), does hereby
certify:

                  That, pursuant to authority conferred upon the Board of
Directors of the Corporation ("Board of Directors") by the Certificate of
Incorporation of the Corporation (the "Certificate") and pursuant to the
provisions of the Nevada Revised Statutes, said Board of Directors, on September
8, 2000, duly adopted resolutions providing for the issuance of one series,
aggregating Seven Hundred and Fifteen Thousand (715,000) shares, of Series D
Convertible Preferred Stock, stated value $3.50 and par value $.001 per share,
which resolutions are as follows:

                  WHEREAS, the Certificate of Incorporation of the Corporation
         authorizes for issuance a class of shares of capital stock known as
         Preferred Stock, par value $.001 per share (the "Preferred Stock"),
         issuable by the Board of Directors from time to time;

                  WHEREAS, the Certificate of Incorporation of the Corporation
         authorizes the Board of Directors to determine the rights, preferences,
         privileges and restrictions granted to or imposed upon any wholly
         unissued Preferred Stock, to fix the number of shares constituting any
         such class and to determine the designation thereof or any of them; and

                  WHEREAS, the Corporation has not issued any shares of such
         Preferred Stock and the Board of Directors of the Corporation desires,
         pursuant to its authority as aforesaid, to determine and fix the
         rights, preferences, privileges and restrictions relating to a class of
         said Preferred Stock to be designated "Series D Preferred Stock, 15%
         Coupon" (the "Series D Preferred Stock").

                  NOW, THEREFORE, BE IT RESOLVED, that the Board of Directors
         hereby fixes and determines the designation of the number of shares
         constituting, and the rights, preferences, privileges and restrictions
         relating to, the Series D Preferred Stock as follows:

                  1. DESIGNATION. The designation of the series of stock created
by this resolution shall be "Series D Preferred Stock, 15% Coupon" (the "Series
D Preferred Stock") and the number of shares constituting the Series D Preferred
Stock shall be Seven Hundred and Fifteen Thousand (715,000). Each share of the
Series D Preferred Stock shall have a stated value equal to $3.50 (the "Stated
Value"). The Preferred Stock does not entitle the holder thereof to voting
rights, except as may be required by law. Each share of Preferred Stock is
convertible: (i) at the option of the Holder, subject to certain rights of the
Company, into common stock of the Company (the "Common Stock") at the rate of 1
share of Common Stock for each share of Preferred Stock, and (ii) mandatorily
converted into Common Stock on March 1, 2002, unless the Company elects to
redeem the Preferred Stock at 115% of its Stated Value in cash on or before
March 31, 2001. The Preferred Stock is subject to redemption by the Company at
its option at any time commencing from the date of issue of the Preferred Stock
until March 31, 2001 at a price of $4.03 per share. In the event the Company
does not elect to redeem the Preferred stock on or before March 31, 2001, the
Company shall use it best efforts to register the underlying common stock on or
before June 30, 2001.

                  2. INTEREST. The 15% Coupon ("interest") will be paid on the
Preferred Stock quarterly in arrears on a cash basis commencing on date of
funding, at a rate of 15% per annum, and prorated if redemption or conversion
occurs prior to the end of any quarter. The first quarterly interest




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payment will be made on March 31, 2001 and then quarterly thereafter. Interest
payments shall cease effective with the date of redemption by the Company or
conversion into common stock, whether voluntary or mandatory conversion.

                  3. LIQUIDATION PREFERENCE. In the event of any liquidation,
dissolution or winding up of the affairs of the Corporation, whether voluntary
or otherwise, after payment or provision for payment of the debts and other
liabilities of the Corporation, the holders of the Series D Preferred Stock
shall be entitled to receive, before the holders of any of the common stock or
other classes of Preferred Stock of the Corporation ranking junior thereto, out
of the remaining net assets of the Corporation, the Stated Value of the Series D
Preferred Stock. After such payment shall have been made in full to the holders
of the outstanding Series D Preferred Stock, or funds or assets necessary for
such payment shall have been set aside in trust for the account of the holders
of the outstanding Series D Preferred Stock, so as to be and continue to be
available therefor, the holders of the outstanding Series D Preferred Stock
shall be entitled to no further participation in such distribution of the assets
of the Corporation.

                  In the event that, after payment or provision for payment of
the debts and other liabilities of the Corporation and preferences or other
rights granted to the holders of Series D Preferred Stock, the remaining net
assets of the Corporation are not sufficient to pay the liquidation preference
of the holders of the Series D Preferred Stock, then no such distribution shall
be made on account of any shares of any other class or series of capital stock
of the Corporation ranking, on a parity with the shares of the Series D
Preferred Stock upon such liquidation unless proportionate distributive amounts
shall be paid on account of each share of the Series D Preferred Stock, ratably,
in proportion to the full distributable amounts for which holders of all such
parity shares, including other shares of Series D Preferred Stock, are
respectively entitled upon such liquidation.

                  4. CONVERSION OF PREFERRED STOCK INTO COMMON STOCK. Each share
of the Series D Preferred Stock shall be: (i) convertible at the option of the
holder thereof pursuant to paragraph 4(a) below and (ii) automatically and
mandatorily converted upon the occurrence of the event described pursuant to
paragraph 4(b) below. In either event, any such shares of Series D Preferred
Stock shall be converted into fully paid and nonassessable shares of the
Corporation's common stock, par value $.001 per share (the "Common Stock").

                           (a) VOLUNTARY CONVERSION. Subsequent to March 31,
2001, the Holder of any share(s) of Series D Preferred Stock shall have the
right to convert any such share(s) into fully paid and nonassessable shares of
Common Stock of the Corporation in accordance with the Conversion Ratio (defined
below); as the same may be adjusted from time to time. In order to convert the
shares of Series D Preferred Stock into Common Stock, the Holder shall surrender
at the office of any transfer agent for the Corporation, a certificate(s)
therefore, duly endorsed to the Corporation or in blank, and give written notice
to the Corporation at said office that he or she elects to convert such shares.
Shares of the Series D Preferred Stock shall be deemed to have been converted
immediately prior to the close of business on the date of surrender of such
shares for conversion and the person(s) entitled to receive shares of Common
Stock issuable upon such conversion shall be treated, for all purposes, as the
record holder(s) of such shares of Common Stock at such time. As promptly as
practicable after the conversion, the Corporation shall issue and deliver at
said offices a certificate(s) for the number of full shares of the Common Stock
issuable upon such conversion, to the person(s) entitled to receive the same.
The Corporation shall issue the certificate(s) for Common Stock in the name(s)
so designated with such legends affixed or restrictions imposed as required by
federal, state or jurisdictional securities laws as determined by legal counsel
for the Corporation; provided that the Corporation is not advised by its counsel
that the issuance of such certificate(s) would be in violation of federal, state
or jurisdictional securities law.





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                           In case any shares of Series D Preferred Stock shall
have been called for redemption pursuant to paragraph 5 hereof, an election to
convert under this paragraph 4(a) with respect to the shares so called for
redemption shall cease and terminate at the close of business on the tenth day
prior to the date fixed for the redemption of such shares, unless default shall
be made in the payment of the redemption price.

                           (b) MANDATORY CONVERSION. Subject to any other
provision of this paragraph 4, each holder of record of any share(s) of Series D
Preferred Stock shall convert such holder's share(s) of Series D Preferred
Stock, in whole or in part, in accordance with the Conversion Ratio (defined
below), subject to the adjustments set forth below, on March 1, 2002. The
Company shall also have a right to force mandatory conversion of the Preferred
Stock into Common Stock prior to March 1, 2002, at any time after the Company
registers the underlying Common Stock and such registration statement is
declared effective by the Securities and Exchange Commission; provided however,
that (i) the stock of the Company is trading at an average closing price of
$3.50 per share for the 20 trading days immediately preceding the date of the
Company's notice to the holder, and (ii) the Company provides notice to the
holder equal to a minimum of 10 days and maximum of 30 days notice. Such notice
shall specify the time and place thereof and shall be given by mail to each
holder of record of shares of Series D Preferred Stock at the address last shown
on the records of the Corporation for such holder or given by such holder to the
Corporation for the purpose of notice or, if no such address appears or is
given, at the place where the principal executive office of the Holder is
located. Any notice which was mailed in the manner herein provided shall be
conclusively presumed to have been duly given whether or not the holder received
the notice.

                           (c) ADDITIONAL PROVISIONS APPLICABLE TO ALL
CONVERSIONS. Any conversion of Series D Preferred Stock into Common Stock
pursuant to this paragraph 4 shall be subject following additional terms and
provisions:

                                    (1) All shares of the Series D Preferred
Stock shall be convertible (or, as the case may be, automatically converted)
into Common Stock at the rate of 1 share of Common Stock for each share of
Series D Preferred Stock (the "Conversion Ratio"), subject to the adjustments
set forth in this paragraph 4(c) below.

                                    (2) Subject to compliance with all
applicable securities laws, as soon as practicable after the surrender for
conversion of any certificate(s) representing Series D Preferred Stock (in the
case of an elective conversion) or after the Mandatory Conversion (as provided
for in Section 4(b)), the Corporation shall deliver or cause to be delivered at
the principal office of the Corporation (or such other place as may be
designated by the Corporation), to each holder of Series D Preferred Stock,
certificates representing, the shares of Common Stock issuable upon such
conversion, issued in such name or names as such holder may direct. Except as
otherwise provided herein, shares of the Series D Preferred Stock shall be
deemed to have been converted, in the case of an elective conversion pursuant to
paragraph 4(a), as of the close of business on the date of the surrender for
conversion of the certificates representing Series D Preferred Stock, or in the
case of an automatic conversion pursuant to paragraph 4(b), as of the close of
business on the Automatic Conversion Date, and in either case the rights of such
holders of the Series D Preferred Stock shall cease, and the person(s) in whose
name(s) the certificates for such shares are to be issued shall be treated for
all purposes as having become the record holder(s) of such Common Stock, at such
time, or if such day shall not constitute a business day, then the close of
business on the next succeeding business day.

                                    (3) The Corporation shall not be required to
issue any fractions of shares of Common Stock upon conversions of any shares of
Series D Preferred Stock. If more than one share of Series D Preferred Stock
shall be surrendered for conversion at one time by the same holder, the




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number of full shares of Common Stock which shall be issuable upon conversion of
such Series D Preferred Stock shall be computed on the basis of the aggregate
number of shares of the Series D Preferred Stock so surrendered. If any interest
in a fractional share would otherwise be deliverable upon the conversion of any
shares of Series D Preferred Stock, the Corporation shall not be required to
issue any such fractional share interest or make a cash payment for any such
fractional interest.

                                    (4) In the event that the Corporation shall
at any time subdivide or combine in a greater or lesser number of shares the
outstanding shares of Common Stock, the number of shares of Common Stock
issuable upon conversion of any shares of Series D Preferred Stock prior to the
occurrence of such event shall be proportionately increased or decreased as the
case may be, effective following the close of business on the record date for
determination of the Common Stock entitled to such sub-division or combination
in either case at the close of business on the record date when such subdivision
or combination was adopted by the Corporation.

                                    (5) In the event that the Corporation shall
be consolidated with or merged into any other corporation, provision shall be
made as part of the terms of such consolidation or merger so that any holder of
Series D Preferred Stock may thereafter receive in lieu of Common Stock
otherwise issuable him upon conversion of his or her Series D Preferred Stock,
but only in accordance with the conversion ratio stated in this paragraph 4, the
same kind and amount of securities as may be distributable upon such
consolidation or merger with respect to the Common Stock.

                                    (6) In the event that the Corporation shall
at any time pay to the holders of Common Stock a dividend in Common Stock, the
number of shares of Common Stock of the Corporation issuable upon any conversion
of the Series D Preferred Stock shall be proportionately increased, effective
following the close of business on the record date for determination of the
holders of Common Stock entitled to such dividend.

                                    (7) Such adjustments shall be made
successively if more than one event listed in paragraphs 4(c)(4), (5) or (6)
shall occur; provided, however, that no adjustment need be made by the
Corporation until such adjustments cumulatively aggregate at least five percent
(5%) of the then current Conversion Ratio.

                                    (8) No adjustment of the Conversion Ratio
shall be made by any event or occurrence other than those enumerated in this
paragraph 4(c).

                                    (9) The issuance of certificates for shares
of Common Stock upon conversion of any shares of the Series D Preferred Stock
shall be made without charge for any tax in respect of such issuance. However,
if any certificate is to be issued in a name other than that of the holder of
record as the Series D Preferred Stock so converted, the person or persons
requesting, the issuance thereof shall pay to the Corporation the amount of any
tax which may be payable in respect of any transfer involved in such issuance,
or shall establish to the satisfaction of the Corporation that such tax has been
paid or is not due and payable.

                  5. REDEMPTION OF PREFERRED STOCK. The Series D Preferred Stock
of any holder shall be redeemable, in whole or in part, at the option of the
Corporation by resolution of its Board of Directors, from time to time and at
anytime, commencing after the date that the Series D Preferred Stock certificate
was issued to the original holder of such shares of Series D Preferred Stock and
ending on March 31, 2001. The redemption price shall equal Four Dollars and
Three Cents ($4.03) per share of each share of Series D Preferred Stock so
redeemed. The Corporation shall give notice of redemption as hereinafter
provided. In the event the Company does not elect to redeem the Preferred stock
on or before


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March 31, 2001, the Company shall use it best efforts to register the underlying
common stock on or before June 30, 2001.

                  In the event that less than the entire amount of the Series D
Preferred Stock outstanding is redeemed at any one time, the shares to be
redeemed shall be selected by lot in a manner to be determined by the Board of
Directors of the Corporation.

                  The Corporation shall give notice of redemption not less than
ten (10) nor more than thirty (30) days prior to the date fixed for redemption
of the Series D Preferred Stock or any part thereof. Such notice shall specify
the time and place thereof and shall be given by mail to each holder of record
of shares of Series D Preferred Stock chosen for redemption at the address last
shown on the records of the Corporation for such holder or given by such holder
to the Corporation for the purpose of notice or, if no such address appears or
is given, at the place where the principal executive office of the Corporation
is located. Any notice which was mailed in the manner herein provided shall be
conclusively presumed to have been duly given whether or not the holder received
the notice.

                  Upon such redemption date, or upon such earlier date as the
Board of Directors shall designate for payment of the redemption price (unless
the Corporation shall default in the payment of the redemption price as set
forth in such notice), the holders of shares of Series D Preferred Stock
selected for redemption to whom notice has been duly given shall cease to be
stockholders with respect to such shares and shall have no interest in or claim
against the Corporation by virtue thereof and shall have no other rights with
respect to such shares except the right to receive the moneys payable upon such
redemption from, the Corporation or otherwise, without interest thereon, upon
surrender (and endorsement, if required by the Corporation) of the certificates,
and the shares represented thereby shall no longer be deemed to be outstanding.

                  At its option, the corporation may deposit the aggregate
amount payable upon redemption of the Series D Preferred Shares to be redeemed
with a bank or trust company designated by the Board of Directors to be held in
trust by the depository for the funds for payment to the holders of the Series D
Preferred Shares then to be redeemed. If such aggregate amount is deposited and
made immediately available to the holder of the Series D Preferred Shares to be
redeemed, the Corporation shall thereupon be released and discharged from any
obligation to make payment of the amount payable upon redemption of the Series D
Preferred Shares to be redeemed and the holder of such Series D Preferred Shares
shall only look to the depository for such payment.

                  Upon redemption of any share of Series D Preferred Stock in
the manner set out herein, or upon purchase of any share of Series D Preferred
Stock by the Corporation, the shares so acquired by the Corporation shall be
canceled.

                  6. VOTING RIGHTS. Except as otherwise required by law or as
otherwise specifically provided herein, the holders of the Series D Preferred
Stock shall not be entitled to vote at any meeting of the stockholders for the
election of directors or for any other purpose or otherwise to participate in
any action taken by the Corporation or the stockholders thereof.

                  7. RANKING. As long as any shares of the Series D Preferred
Stock remain outstanding, the Corporation shall not, without obtaining the prior
written consent of the holders of at least a majority in number of the shares of
the Series D Preferred Stock then outstanding, create, authorize or issue any
other class or series of capital stock of the Corporation, the terms of which
provide that such class or series shall rank prior to the Series D Preferred
Stock in respect to rights upon dissolution, liquidation or winding up of the
Corporation; provided, however, the Corporation may at any time create,





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authorize or issue, without the consent of any of the holders of the Series D
Preferred Stock, other classes or series of capital stock which rank junior to,
or on parity with, the Series D Preferred Stock in respect to dissolution,
liquidation or winding up of the Corporation.

                  8. AMENDMENTS. This Statement of Designation may be amended by
(i) the affirmative vote of not less than sixty percent (60%) of the holders of
Series D Preferred Shares currently outstanding, at the time such amendment is
proposed, or (ii) the affirmative vote of not less than two-thirds of the
directors of the Corporation then holding office and entitled to vote on such
amendment.

                                        U. S. PLASTIC LUMBER CORP.


                                        By: /s/ John W. Poling
                                            ------------------------------------
                                            John W. Poling, CFO



                                        U. S. PLASTIC LUMBER CORP.


                                        By: /s/ Bruce C. Rosetto
                                            ------------------------------------
                                            Bruce C. Rosetto, Secretary




STATE OF FLORIDA                    )
                           ss       )
COUNTY OF PALM BEACH                )

         Before me, the undermined authority, personally appeared John W.
Poling, who I personally know to be the person described in and who executed the
foregoing instrument as Chief Financial Officer of U. S. Plastic Lumber Corp., a
Nevada corporation, and did acknowledge before me that he executed the same as
such officer of said corporation by due and regular corporate authority.

         WITNESS my hand and official seal in the County and State last
aforesaid this 20th day of September, 2000.



                                       /s/ Kim Morrell
                                       ----------------------------
                                       Notary Public
                                       State of Florida at Large

My commission expires:






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STATE OF FLORIDA                    )
                           ss       )
COUNTY OF PALM BEACH                )


         Before me, the undersigned authority, personally appeared Bruce C.
Rosetto, who I personally know to be the person described in and who executed
the foregoing instrument as Secretary of U. S. Plastic Lumber Corp., a Nevada
corporation, and did acknowledge before me that he executed the same as such
officer of said corporation by due and regular corporate authority.

         WITNESS my hand and official seal in the County and State last
aforesaid this 20th day of September, 2000.


                                       /s/ Kim Morrell
                                       ----------------------------
                                       Notary Public
                                       State of Florida at Large

My commission expires:






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