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                                                                       Exhibit 4

                       FIRST AMENDMENT TO LOAN AGREEMENT

     Amendment, dated as of the 1st day of May, 2000, by and among Tuscarora
Incorporated, a Pennsylvania corporation (the "Borrower"), Mellon Bank, N.A., a
national banking association ("Mellon"), KeyBank National Association, a
national banking association ("Key") (Mellon, Key and any other financial
institution that becomes a party to the Loan Agreement (as hereinafter defined),
are individually, a "Bank" and collectively, the "Banks"), and Mellon Bank,
N.A., as Agent for the Banks ("Agent") ("First Amendment").

                             W I T N E S S E T H :

     WHEREAS, the Borrower, the Banks and the Agent have entered into that
certain Loan Agreement, dated September 23, 1999, pursuant to which, among
other things, the Banks extended to the Borrower a credit facility in the
original principal amount not to exceed Ninety Million and 00/100 Dollars
($90,000,000.00) (as further amended from time to time, the "Loan Agreement");
and

     WHEREAS, the Borrower desires to amend certain provisions of the Loan
Agreement and the Banks and the Agent desire to permit such amendments pursuant
to the terms and conditions set forth herein.

     NOW, THEREFORE, in consideration of the premises contained herein and
other valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, and intending to be legally bound hereby, the parties hereto
agree as follows:

     1. All capitalized terms used herein which are defined in the Loan
Agreement shall have the same meaning herein as in the Loan Agreement unless
the context clearly indicates otherwise.

     2. The definition of "Cash Flow" contained in Section 1.01 of the Loan
Agreement is hereby deleted in its entirety and in its stead is inserted the
following:

          "Cash Flow" shall mean, for the period of determination, (i) Net
     Income, (ii) minus Six Million and 00/100 Dollars ($6,000,000.00), (iii)
     minus income from minority owned equity investments, (iv) minus
     Distributions, (v) plus depreciation, depletion and amortization, (vi) plus
     losses from minority owned equity investments, in each case determined and
     Consolidated for the Borrower and its Subsidiaries in accordance with GAAP.
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     3. The definition of "Operating Earnings" contained in Section 1.01 of the
Loan Agreement is hereby deleted in its entirety and in its stead is inserted
the following:

          "Operating Earnings" shall mean, for the period of determination, (i)
     Net Income, (ii) minus income from minority owned equity investments, (iii)
     plus Interest Expense, (iv) plus all income taxes included in Net Income,
     (v) plus losses from minority owned equity investments, in each case
     determined and Consolidated for the Borrower and its Subsidiaries in
     accordance with GAAP.

     4. Section 6.04(g) of the Loan Agreement is hereby deleted in its entirety
and in its stead is inserted the following:

          (g) other loans and investments after the Closing Date reflected on
     the Consolidated balance sheet from time to time in amounts not in excess
     of Two Million Five Hundred Thousand and 00/100 Dollars ($2,500,000.00)
     for any one such loan or investment and Ten Million and 00/100 Dollars
     ($10,000,000.00) for the aggregate of all such loans and investments in any
     fiscal year; and

     5. The Borrower hereby reconfirms and reaffirms all representations and
warranties, agreements and covenants made by it pursuant to the terms and
conditions of the Loan Agreement, except as such representations and
warranties, agreements and covenants may have heretofore been amended, modified
or waived in writing in accordance with the Loan Agreement; provided, however,
that any such representations, warranties, agreements and covenants that
expressly relate to a specific date continue to relate only to such date.

     6. The Borrower hereby represents and warrants to the Banks and the Agent
that (i) the Borrower has the legal power and authority to execute and deliver
this First Amendment; (ii) the officers of the Borrower executing this First
Amendment have been duly authorized to execute and deliver the same and bind
the Borrower with respect to the provisions hereof; (iii) the execution and
delivery hereof by the Borrower and the performance and observance by the
Borrower of the provisions hereof and of the Loan Agreement and all documents
executed or to be executed therewith, do not violate or conflict with the
organizational agreements of Borrower or any Law applicable to Borrower or
result in a breach of any provision of or constitute a default under any other
agreement, instrument or document binding upon or enforceable against the
Borrower and (iv) this First Amendment, the Loan Agreement and the documents
executed or to be executed by the Borrower in connection herewith or therewith
constitute valid and binding obligations of the Borrower in every respect,
enforceable in accordance with their respective terms.


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     7.  The Borrower represents and warrants that (i) no Event of Default
exists under the Loan Agreement, nor will any occur as a result of the
execution and delivery of this First Amendment or the performance or observance
of any provision hereof and (ii) it presently has no claims or actions of any
kind at Law or in equity against the Banks or the Agent arising out of or in
any way relating to the Loan Documents.

     8.  Each reference to the Loan Agreement that is made in the Loan Agreement
or any other document executed or to be executed in connection therewith shall
hereafter be construed as a reference to the Loan Agreement as amended hereby.

     9.  Except as amended hereby, all of the terms and conditions of the Loan
Agreement shall remain in full force and effect. This First Amendment amends
the Loan Agreement and is not a novation thereof.

     10. This First Amendment may be executed in any number of counterparts and
by the different parties hereto on separate counterparts each of which, when so
executed, shall be deemed an original, but all such counterparts shall
constitute but one and the same instrument.


                           [INTENTIONALLY LEFT BLANK]


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     IN WITNESS WHEREOF, and intending to be legally bound, the parties hereto,
have caused this First Amendment to be duly executed by their duly authorized
officers to be effective on the date first written above.


Attest:                                      Tuscarora Incorporated

By: /s/ H. KENNETH LINGE                     By: /s/ BRIAN C. MULLINS
    ---------------------------                  ----------------------------
Title:   Attorney                            Title:  Sr. Vice President,
       ------------------------                      Chief Financial Officer
                                                     and Treasurer
                                                     ------------------------

                                             Mellon Bank, N.A., as Agent
                                             and for itself as a Bank


                                             By: /s/ DWAYNE R. FINNEY
                                                 ----------------------------
                                             Title:  Vice President
                                                     ------------------------


                                             KeyBank National Association


                                             By: /s/ FRANCIS W. LUTZ, JR.
                                                -----------------------------
                                             Title:  Portfolio Officer
                                                     ------------------------


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