This Addendum to the Charter for Development of the Alaskan North Slope ("Addendum") is entered between the State of Alaska, BP, ARCO, BP Amoco p.l.c. ("BP Amoco"), and Phillips Petroleum Company ("Phillips") on March 15, 2000, to confirm their common interpretation of the Charter in connection with anticipated divestitures. Words and terms have the same meaning in this Addendum as in the Charter.

1. The parties agree that the sale of ARCO as a going concern will satisfy the commitments made by BP and ARCO in Charter paragraph I.A. (Sale of Current Production), paragraph I.B. (Sale of NPRA Lease Interests), paragraph I.C. (Sale or Relinquishment of State Leases), subparagraphs I.H.1.-3. (Divestiture of TAPS and Feeder Lines), and paragraph I.I. (Offer to Sell Excess Jones Act Ships).

2. The sale of "ARCO as a going concern" under this Addendum means transfer to Phillips or a Phillips subsidiary of (a) all of the stock in (i) ARCO (subject to the requirement that ARCO's owned assets at the time of any stock sale be substantially the same as at the time the Charter was entered) and (ii) ARCO's affiliates owning associated North Slope feeder pipelines and TAPS, as well as (b) associated ANS shipping capacity.

3. In the event of such a going concern sale, BP and ARCO may, where appropriate, provide for separate performance of the Charter commitments by BP and ARCO, so long as BP and ARCO each remain jointly and severally accountable for complete performance of their commitments under the Charter.

4. This Addendum does not change the notice and review provisions of Charter subparagraph V.E.2, or the commitments of ARCO, BP, and BP Amoco under any other Charter provision not specifically identified in paragraph 1 of this Addendum.

5. Phillips agrees that, if it is approved as the purchaser of ARCO as a going concern and completes that purchase, it will, subject to the terms of this Addendum, ensure ARCO's performance under the Charter to the same extent and in the same manner as BP Amoco has ensured the performance of BP and ARCO in Charter Section IV.

6. Subject only to the terms of this Addendum, the parties agree that the Charter is and will remain in full force and effect according to its terms.

State of Alaska

By __________________________ Tony Knowles, Governor	By __________________________ Bruce Botelho, Attorney General

BP Amoco, p.l.c.

By _________________________
Rodney Chase, Deputy CEO

Phillips Petroleum Company

By _______________________
J.J. Mulva
President and
Chief Operating Officer

BP Exploration (Alaska) Inc.

By ________________________
Richard Campbell, President

ARCO Alaska, Inc.

By _________________________
Kevin Meyers, President