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| Forward-Looking Statements This presentation contains forward-looking statements and information. These forward-looking statements, which in many instances can be identified by words like “could,” “may,” “will,” “should,” “expects,” “plans,” “project,” “anticipates,” “believes,” “potential,” and other comparable words, regarding future or contemplated performance, transaction, or events, are based on MarkWest’s current information, expectations and beliefs, concerning future developments and their potential effects on MarkWest. Among the factors that could cause results to differ materially are those risks discussed in our Form S-1, as amended, our Annual Report on Form 10-K/A for the year ended December 31, 2006, and our Quarterly Reports on Form 10-Q, as amended, each as filed with the SEC. You are also urged to carefully review and consider the cautionary statements and other disclosures, including those under the heading “Risk Factors,” made in those filings, which identify and discuss significant risks, uncertainties and various other factors that could cause actual results to vary significantly from those expressed or implied in the forward-looking statements. If any of the uncertainties or risks develop into actual events, or if underlying assumptions prove incorrect, it could cause actual results to vary significantly from those expressed in the presentation, and our business, financial condition, or results of operations could be materially adversely affected. Key uncertainties and risks that may directly affect MarkWest’s performance, future growth, results of operations, and financial condition, include, but are not limited to: Fluctuations and volatility of natural gas, NGL products, and oil prices; A reduction in natural gas or refinery off-gas production which we gather, transport, process, and/or fractionate; A reduction in the demand for the products we produce and sell; Financial credit risks / failure of customers to satisfy payment or other obligations under our contracts; Effects of our debt and other financial obligations on our future financial or operational flexibility; Construction, procurement, and regulatory risks in our development projects; Hurricanes, fires, and other natural and accidental events impacting our operations; Terrorist attacks directed at our facilities or related facilities; Changes in and impacts of laws and regulations affecting our operations; and Failure to integrate recent or future acquisitions. |