MarkWest Pioneer, L.L.C.

Original Volume No. 1

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Effective Date: 04/01/2009, Docket: RP09-321-000, Status: Effective

Original Sheet No. 70 Original Sheet No. 70

GENERAL TERMS AND CONDITIONS

(Continued)

13.2.2. (Continued)

Monthly Imbalances Imbalance Charge per MMBtu

>5% - 7% $25 plus the Daily Index Price

>7% - 15% $50 plus the Daily Index Price

>15% $100 plus the Daily Index Price

For purposes of this section, Shipper’s monthly imbalance shall

equal the difference between Shipper’s actual cumulative receipts

during OFO operating conditions and Shipper’s actual cumulative

deliveries during OFO operating conditions stated as a percent of

Shipper’s actual cumulative deliveries during OFO operating

condition during the Billing Month.

For purposes of this section, the Daily Index Price shall equal the

high in the range of prices reported each day for “CENTERPOINT,

EAST” as published by Gas Daily. If Gas Daily is no longer

published, an equivalent index or indicator shall be published on

Transporter’s Website and this definition will be revised.

13.2.3. Recovery of Volumes Owed to Transporter - Whenever Shipper’s actual

cumulative receipts during Billing Month are less than actual

cumulative deliveries, Transporter will recover the cost of the

volumes owed to Transporter by assessing Shipper the replacement

costs associated with the excess gas taken during the Billing Month.

Such costs will be based on the average weekly price reported for

“CENTERPOINT, EAST” as published by Gas Daily during the Billing

Month that the imbalance occurred multiplied by Shipper’s imbalance

volumes.