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                                                                   EXHIBIT 10.48

                               SEVENTH AMENDMENT

                  SEVENTH AMENDMENT, dated as of March 30, 1999 (this "Seventh
Amendment"), to the Credit Agreement, dated as of September 30, 1996 (as
amended by the Global Amendment and Assignment and Acceptance, dated as of
October 9, 1996, the Second Amendment, dated as of April 23, 1997, the Third
Amendment, dated as of May 13, 1997, the Fourth Amendment, dated as of July 31,
1997, the Fifth Amendment, dated as of June 16, 1998, and the Sixth Amendment,
dated as of September 25, 1998, and as may be further amended, supplemented or
otherwise modified from time to time, the "Credit Agreement"), among RIGCO
NORTH AMERICA, L.L.C., a Delaware limited liability company (the "Borrower"),
the several banks and other financial institutions from time to time parties
thereto (the "Lenders"), LEHMAN COMMERCIAL PAPER INC. ("LCPI"), as Advisor,
Syndication Agent and Arranger, HIBERNIA NATIONAL BANK, as Collateral and
Documentation Agent and BHF-BANK AKTIENGESELLSCHAFT, as Administrative Agent.


                              W I T N E S S E T H

                  WHEREAS, pursuant to the Credit Agreement, the Lenders have
agreed to make, and have made, certain Loans to the Borrower; and

                  WHEREAS, the Borrower has requested that the Lenders amend
and waive, and the Lenders have agreed to amend and waive, certain of the
provisions of the Credit Agreement, upon the terms and subject to the
conditions set forth below;

                  NOW, THEREFORE, the parties hereto hereby agree as follows:

                  1. Defined Terms. As used herein, terms defined in this
Seventh Amendment or in the Credit Agreement are used herein as so defined.

                  2. Amendment to Subsection 2.3. Subsection 2.3 of the Credit
Agreement is hereby amended by deleting the date "March 31, 1999" contained in
the table therein and substituting in lieu thereof the date "April 30, 1999".

                  3. Amendment to Subsection 2.6(c). Subsection 2.6(c) of the
Credit Agreement is hereby amended by adding thereto immediately at the end
thereof but prior to the period the following: "provided, further, that the
interest payment payable on March 31, 1999 shall instead be due and payable on
April 30, 1999".

                  4. Waiver of Financial Covenants. The Lenders hereby waive
compliance by the Borrower with the financial condition covenants contained in
subsection 6.1 of the Credit Agreement for the period from March 31, 1999
through April 30, 1999.

                  5. Overdue Interest. Notwithstanding the amendments set forth
in paragraphs 2 and 3 of this Seventh Amendment, interest on the outstanding
principal amount of the Loans and on the interest payment which was formerly
due on March 31, 1999 shall accrue


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during the period of April 1, 1999 through April 30, 1999 at the rate set forth
in subsection 2.6(b) of the Credit Agreement.

                  6. Effectiveness. The amendments and waivers provided for
herein shall become effective on the date (the "Effective Date") of
satisfaction of the following conditions precedent:

                  (a) The Administrative Agent shall have received counterparts
         of (i) this Seventh Amendment, duly executed and delivered by the
         Borrower and each of the other parties hereto, (ii) the Second
         Amendment, dated as of the date hereof, to the Warrant Agreement,
         dated as of September 30, 1996, between the Borrower and Lehman
         Brothers Inc., duly executed and delivered by the parties thereto and
         (iii) the Second Amendment, dated as of the date hereof, to the
         Warrant Agreement, dated as of June 16, 1998, between FPS VI, L.L.C.
         and Lehman Brothers Inc., duly executed and delivered by the parties
         thereto.

                  (b) All governmental and third party approvals (including
         landlords' and other consents) necessary or advisable in connection
         with this Seventh Amendment shall have been obtained and be in full
         force and effect, and all applicable waiting periods shall have
         expired without any action being taken or threatened by any competent
         authority which would restrain, prevent or otherwise impose materially
         adverse conditions on the Credit Agreement as amended by this Seventh
         Amendment.

                  (c) All limited liability company and other proceedings, and
         all documents, instruments and other legal matters in connection with
         the transactions contemplated by this Seventh Amendment shall be
         satisfactory in form and substance to the Arranger and the
         Administrative Agent.

                  (d) LCPI shall have received for the accounts of the Lenders
         an amendment fee in an amount equal to $100,000.

                  7. Representations and Warranties. After giving effect to the
amendments and waivers contained herein, on the Effective Date, the Borrower
hereby confirms, reaffirms and restates the representations and warranties set
forth in Section 3 of the Credit Agreement; provided that each reference in
such Section 3 to "this Agreement" shall be deemed to be a reference both to
this Seventh Amendment and to the Credit Agreement as amended by this Seventh
Amendment.

                  8. Continuing Effect; No Other Amendments. Except as
expressly amended or waived hereby, all of the terms and provisions of the
Credit Agreement and the other Loan Documents are and shall remain in full
force and effect. The amendments and waivers contained herein shall not
constitute an amendment or waiver of any other provision of the Credit
Agreement or the other Loan Documents or for any purpose except as expressly
set forth herein.


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                  9. No Default. No Default or Event of Default shall have
occurred and be continuing as of the Effective Date after giving effect to this
Seventh Amendment.

                  10. Costs and Expenses. The Borrower agrees to pay the
reasonable costs and expenses of the Administrative Agent, the Collateral and
Documentation Agent and the Arranger in connection with this Seventh Amendment,
including, without limitation, legal fees and expenses.

                  11. Counterparts. This Seventh Amendment may be executed in
any number of counterparts by the parties hereto, each of which counterparts
when so executed shall be an original, but all the counterparts shall together
constitute one and the same instrument.

                  12. GOVERNING LAW. THIS SEVENTH AMENDMENT SHALL BE GOVERNED
BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
NEW YORK.


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                  IN WITNESS WHEREOF, the parties have caused this Seventh
Amendment to be duly executed and delivered by their respective proper and duly
authorized officers as of the day and year first above written.

                                        RIGCO NORTH AMERICA, L.L.C.


                                        By:
                                            Title:


                                        BHF-BANK AKTIENGESELLSCHAFT, as
                                        Administrative Agent and as a Lender


                                        By:
                                            Title:



                                        By:
                                            Title:


                                        HIBERNIA NATIONAL BANK, as Collateral
                                        and Documentation Agent and as a Lender


                                        By:
                                            Title:


                                        LEHMAN COMMERCIAL PAPER INC., as
                                        Syndication Agent and as a Lender


                                        By:
                                            Title:




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                                        MERRILL LYNCH PRIME RATE PORTFOLIO

                                        By: MERRILL LYNCH ASSET MANAGEMENT
                                        L.P., as Investment Adviser


                                        By:

                                        Title:

                                        MERRILL LYNCH SENIOR FLOATING RATE
                                          FUND, INC.


                                        By:

                                        Title:

                                        MERRILL LYNCH DEBT STRATEGIES PORTFOLIO

                                        By: MERRILL LYNCH ASSET MANAGEMENT L.P.,
                                        as Investment Adviser


                                        By:

                                        Title:

                                        SENIOR HIGH INCOME PORTFOLIO, INC.


                                        By:

                                        Title:


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VAN KAMPEN AMERICAN CAPITAL PRIME RATE
INCOME TRUST


By:
                               Title: