Marathon Oil (MRO)

F-36

        On May 11, 2001, MAP entered into a consent decree with the U.S. Environmental Protection Agency which commits it to complete certain agreed on environmental projects over an eight-year period primarily aimed at reducing air emissions at its seven refineries. The court approved this consent decree on August 28, 2001. The total one-time expenditures for these environmental projects is approximately $370 million over the eight-year period, with about $240 million incurred through December 31, 2004. In addition, MAP has nearly completed certain agreed on supplemental environmental projects as part of this settlement of an enforcement action for alleged Clean Air Act violations, at a cost of $9 million. MAP believes that this settlement will provide MAP with increased permitting and operating flexibility while achieving significant emission reductions.

Guarantees  –  Marathon and MAP have issued the following guarantees:

^(a)

Marathon holds interests in an offshore oil port, LOOP LLC ("LOOP"), and a crude oil pipeline system, LOCAP LLC ("LOCAP"). Both LOOP and LOCAP have secured various project financings with throughput and deficiency ("T&D") agreements. A T&D agreement creates a potential obligation to advance funds in the event of a cash shortfall. When these rights are assigned to a lender to secure financing, the T&D is considered to be an indirect guarantee of indebtedness. Under the agreements, Marathon is required to advance funds if the investees are unable to service debt. Any such advances are considered prepayments of future transportation charges. The terms of the agreements vary but tend to follow the terms of the underlying debt. Assuming non-payment by the investees, the maximum potential amount of future payments under the guarantees is estimated to be $183 million and $192 million at December 31, 2004 and 2003, respectively. Included in these amounts are a LOOP revolving credit facility of $25 million at December 31, 2004 and 2003, and a LOCAP revolving credit facility of $23 million at December 31, 2004 and 2003. The undrawn portion of the revolving credit facilities is $34 million as of December 31, 2004 and 2003.

^(b)

MAP holds an interest in a refined products pipeline, Centennial Pipeline LLC ("Centennial"), and has guaranteed the repayment of Centennial's outstanding balance under a Master Shelf Agreement, which expires in 2024, and a Credit Agreement, which expires in 2007. The guarantees arose in order to obtain adequate financing. Prior to expiration of the Master Shelf Agreement, MAP could be relinquished from responsibility under the guarantee should Centennial meet certain financial tests. If Centennial defaults on its outstanding balance, the estimated maximum potential amount of future payments is $75 million at December 31, 2004 and 2003.

^(c)

In 2003, Marathon sold its interest in the Yates field and gathering system to Kinder Morgan. In accordance with this transaction, Marathon indemnified Kinder Morgan from inaccuracies in Marathon's representations, warranties, covenants and agreement. There is not a specified term on these guarantees and the maximum potential amount of future cash payments is estimated at $228 million.

^(d)

In conjunction with the sale of certain Canadian assets to Husky Oil operations Limited ("Husky") during 2003, Marathon guaranteed Husky with regards to unknown environmental obligations and inaccuracies in representations, warranties, covenants and agreements by Marathon. These indemnifications are part of the normal course of doing business and selling assets. Per the Purchase and Sale agreement, the maximum potential amount of future payments associated with these guarantees is $568 million.

^(e)

Marathon entered into certain performance and general guarantees and environmental and general indemnifications in connection with certain asset sales. The terms vary from 2005 to indefinite and the maximum potential amount of future payments under the guarantees and indemnifications is estimated to be $30 million.

^(f)

Marathon has guaranteed United States Steel's contingent obligation to repay certain distributions from its 50 percent-owned joint venture, PRO-TEC Coating Company ("PRO-TEC"). Should PRO-TEC default under its agreements and should United States Steel be unable to perform under its guarantee, Marathon is required to perform on behalf of United States Steel. The maximum potential payout is estimated at $14 million at December 31, 2004 and 2003. Additionally, United States Steel is the sole general partner of Clairton 1314B Partnership, L.P., which owns certain cokemaking facilities formerly owned by United States Steel. Marathon has guaranteed to the limited partners all obligations of United States Steel under the partnership documents. In addition to the commitment to fund operating cash shortfalls of the partnership discussed in Note 3, United States Steel, under