Exhibit 10.19 AMENDMENT NO. 1, dated as of April 25, 2002 (this "Amendment No. 1" or this "Amendment"), in respect of the LONG-TERM REVOLVING CREDIT AGREEMENT, dated as of February 25, 1998, as amended and restated as of December 7, 2001 (the "Credit Agreement"), among BURLINGTON RESOURCES INC., a Delaware corporation (the "Borrower"), the financial institutions (the "Lenders") listed on the signature pages thereof, JPMorgan Chase Bank, as administrative agent (the "Administrative Agent") and as auction administrative agent, Citibank, N.A. and Fleet National Bank, as co-syndication agents, and Bank of America, N.A. and Toronto Dominion (Texas), Inc., as co-documentation agents. The Borrower has advised the Administrative Agent and the Lenders that it desires to amend the Credit Agreement to eliminate any inconsistency between (i) the requirements of Section 5.03(b)(ii) thereof with respect to the form, scope and substance of the auditor's "negative assurance" letter referred to therein and (ii) SAS 62 and other applicable accounting rules and guidelines in effect from time to time, and has requested in connection therewith that the Credit Agreement be amended as set forth in Section 1 below, and the parties hereto are willing so to amend the Credit Agreement. Each capitalized term used but not defined herein and defined in the Credit Agreement has the meaning assigned thereto in the Credit Agreement. In consideration of the premises and the agreements and provisions herein contained, the parties hereto hereby agree, on the terms and subject to the conditions set forth herein, as follows: SECTION 1. Amendment and Waiver. (a) Upon the effectiveness of this Amendment No. 1 as provided in Section 3 below, clause (ii) of Section 5.03(b) of the Credit Agreement shall be amended to read in its entirety as follows: (ii) a letter from such accountants stating that in making the investigations necessary for such report they obtained no knowledge, except as specifically stated therein, of any Event of Default which is continuing hereunder or of any event not theretofore remedied which with notice or lapse of time or both would constitute such an Event of Default (which letter may be limited in form, scope and substance to the extent required by applicable accounting rules or guidelines in effect from time to time); (b) The Lenders hereby waive any Default that may exist or have existed at or prior to the date of effectiveness hereof by reason of the delivery to the Lenders of a letter referred to in Section 5.03(b)(ii) of the Credit Agreement that was consistent with the requirements of Section 5.03(b)(ii) except for the fact that such letter was limited in form, scope or substance in order to comply with SAS 62 and any other applicable accounting rules and guidelines. -2- SECTION 2. Representations and Warranties. The Borrower represents and warrants as of the effective date of this Amendment to each of the Lenders that: (a) Immediately before and immediately after giving effect to this Amendment, the representations and warranties set forth in the Credit Agreement are true and correct in all material respects with the same effect as if made on the effective date hereof, except to the extent such representations and warranties expressly relate to an earlier date or period. (b) Immediately before and immediately after giving effect to this Amendment, no Event of Default or Default has occurred and is continuing that would not be cured by effectiveness of this Amendment No 1. SECTION 3. Conditions to Effectiveness. This Amendment No. 1 and the amendment and waiver contained herein shall become effective as of the date hereof when the Administrative Agent shall have received counterparts of this Amendment No. 1 that, when taken together, bear the signatures of the Borrower, the Administrative Agent, and the Majority Lenders. SECTION 4. Agreement. Except as specifically stated herein, the provisions of the Credit Agreement are and shall remain in full force and effect. As used therein, the terms "Credit Agreement", "herein", "hereunder", "hereinafter", "hereto", "hereof" and words of similar import shall, unless the context otherwise requires, refer to the Credit Agreement as amended hereby. SECTION 5. Applicable Law. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK. SECTION 6. Counterparts. This Amendment may be executed in two or more counterparts, each of which shall constitute an original but all of which when taken together shall constitute but one contract. SECTION 7. Expenses. The Borrower agrees to reimburse the Administrative Agent for all out-of-pocket expenses incurred by it in connection with this Amendment, including the reasonable fees, charges and disbursements of Cravath, Swaine & Moore, counsel for the Administrative Agent. IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed by their respective authorized officers as of the day and year first written above. BURLINGTON RESOURCES INC. By: /s/ Daniel D. Hawk ------------------------------------------------- Name: Daniel D. Hawk Title: Vice President and Treasurer JPMORGAN CHASE BANK, individually and as Administrative Agent and Auction Administrative Agent By: /s/ Russell A. Johnson ------------------------------------------------- Name: Russell A. Johnson Title: Vice President CITIBANK, N.A., individually and as Co-Syndication Agent By: /s/ Amy K. Pincu ------------------------------------------------- Name: Amy K. Pincu Title: Attorney-in-Fact FLEET NATIONAL BANK, individually and as Co-Syndication Agent By: /s/ Allison I. Rossi ------------------------------------------------- Name: Allison I. Rossi Title: Vice President BANK OF AMERICA, N.A., individually and as Co-Documentation Agent By: /s/ Richard L. Stein ------------------------------------------------- Name: Richard L. Stein Title: Principal TORONTO DOMINION (TEXAS), INC., individually and as Co-Documentation Agent By: /s/ Ann S. Slanis ------------------------------------------------- Name: Ann S. Slanis Title: Vice President THE BANK OF NOVA SCOTIA By: /s/ M. D. Smith ------------------------------------------------- Name: M. D. Smith Title: Agent, Operations THE BANK OF TOKYO-MITSUBISHI, LTD. By: /s/ Kelton Glasscock ------------------------------------------------- Name: Kelton Glasscock Title: Vice President & Manager BNP PARIBAS By: /s/ Douglas R. Liftman ------------------------------------------------- Name: Douglas R. Liftman Title: Managing Director By: /s/ Betsy Jocher ------------------------------------------------- Name: Betsy Jocher Title: Vice President MELLON BANK, N.A. By: /s/ Roger E. Howard ------------------------------------------------- Name: Roger E. Howard Title: Vice President THE ROYAL BANK OF SCOTLAND PLC By: /s/ Scott Barton ------------------------------------------------- Name: Scott Barton Title: Senior Vice President WACHOVIA BANK, N.A. By: /s/ Philip Trinder ------------------------------------------------- Name: Philip Trinder Title: Vice President ABN AMRO BANK By: /s/ Frank R. Russo, Jr. ------------------------------------------------- Name: Frank R. Russo, Jr. Title: Group Vice President By: /s/ Jeffery G. White ------------------------------------------------- Name: Jeffery G. White Title: Vice President ROYAL BANK OF CANADA By: /s/ Lorne Gartner ------------------------------------------------- Name: Lorne Gartner Title: Vice President BANK ONE, N.A. (MAIN OFFICE, CHICAGO) By: /s/ Ronald L. Dierker ------------------------------------------------- Name: Ronald L. Dierker Title: Director, Capital Markets BARCLAYS BANK PLC By: /s/ Nicholas A. Bell ------------------------------------------------- Name: Nicholas A. Bell Title: Director THE NORTHERN TRUST COMPANY By: /s/ Ashish S. Bhagwat ------------------------------------------------- Name: Ashish S. Bhagwat Title: Vice President MIZUHO CORPORATE BANK, LTD. By: /s/ Hirofumi Sugano ------------------------------------------------- Name: Hirofumi Sugano Title: Senior Vice President