Exhibit 3.4 AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT OF MARKWEST ENERGY OPERATING COMPANY, L.L.C. TABLE OF CONTENTS ARTICLE I DEFINITIONSLimited Liability Company Agreement • March 22nd, 2002 • Markwest Energy Partners L P • Crude petroleum & natural gas • Delaware
Contract Type FiledMarch 22nd, 2002 Company Industry Jurisdiction