1 EXHIBIT 2.2 AMENDMENT NO. 1 TO AGREEMENT AND PLAN OF MERGER THIS AMENDMENT NO. 1 TO AGREEMENT AND PLAN OF MERGER (this "Amendment"), dated as of June 27, 2001 is among HS Resources, Inc., a Delaware corporation ("Company"), Kerr- McGee Corporation,...Agreement and Plan of Merger • June 28th, 2001 • Kerr McGee Holdco Inc • Crude petroleum & natural gas • Delaware
