EXHIBIT 10.6(b) THE PREMCOR REFINING GROUP, INC, A Member of the Valero Family of Companies January 25, 2006 Kent B. Thomas, General Counsel MAPCO Express, Inc. / Delek Refining,Ltd. 830 Crescent Centre Drive, Suite 300 Franklin, TN 37067 Re:...Assignment of RPC Agreement • February 8th, 2006 • Delek US Holdings, Inc.
As part of an internal systems change, The Premcor Refining Group, Inc. ("PRG") assigned all of its marketing, supply and related contracts, including the referenced Agreement, to Valero Marketing and Supply Company ("Valero Marketing"). This assignment took place on December 1, 2005. As you are aware, PRG purchased the assets of Williams Refining & Marketing, LLC. on November 25, 2002 and thereafter entered into an assignment and assumption agreement effective March 3, 2003 (attached). Thereafter, on September 1, 2005, Valero Energy Corporation, the parent company of Valero Marketing, acquired Premcor, Inc., parent company of PRG. PRG and Valero Marketing are both indirect wholly-owned subsidiaries of Valero Energy Corporation. Valero Marketing already handles the vast majority of the Valero companies' marketing and supply business throughout the country. This assignment will have no adverse operational impact on our relationship and all notice and invoice contacts remain the same. Pl
