OLD GREENWICH, Connecticut – Premcor Inc. announced today that it has filed with the Securities and Exchange Commission an amendment to its previously filed registration statement relating to the initial public offering of 15,000,000 shares of its common stock, setting the estimated price range at $22 to $24 per share. All of the shares are primary shares being offered by the company. When issued, the common stock is expected to trade on the New York Stock Exchange under the symbol “PCO”.

The offering is being lead-managed by Morgan Stanley as sole bookrunner. Credit Suisse First Boston is the co-lead manager, and Goldman, Sachs & Co., Salomon Smith Barney, Deutsche Bank Securities and Bear, Stearns & Co. Inc. are co-managers of the offering. The underwriters have been granted an option by the company to purchase up to an additional 2,250,000 shares of common stock to cover over-allotments, if any.

A registration statement relating to these securities has been filed with the Securities and Exchange Commission but has not yet been declared effective. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This press release shall not constitute an offer to sell or a solicitation of an offer to buy, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. A copy of the preliminary prospectus related to the offering can be obtained from Morgan Stanley at 1585 Broadway, New York, NY 10036, (212) 761-6775.

Premcor Inc., through its principal operating subsidiaries, The Premcor Refining Group Inc. and the Port Arthur Coker Company L.P., is one of the largest independent petroleum refiners and marketers of unbranded transportation fuels, heating oil, petrochemical feedstocks, petroleum coke and other petroleum products in the United States. The company has an aggregate 490,000 barrels per day (bpd) of crude distillation capacity at its three refineries located in Port Arthur, Texas (250,000 bpd), Lima, Ohio (170,000 bpd) and Hartford, Illinois (70,000 bpd). The company has announced it will discontinue refining operations at the Hartford, Illinois refinery in October 2002.