MarkWest Pioneer, L.L.C.

Original Volume No. 1

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Effective Date: 12/31/9999, Docket: RP09-532-000, Status: Accepted

First Revised Sheet No. 69 First Revised Sheet No. 69

Superseding: Original Sheet No. 69

GENERAL TERMS AND CONDITIONS

(Continued)

13. IMBALANCES AND OVERRUNS

13.1 Responsibility for Balancing – Shippers are obligated to deliver and receive Gas in

conformance with their confirmed nominations. Transporter will enter into an Operational

Balancing Agreement (“OBA”) at all points of interconnection between its system and the

system of another interstate or intrastate pipeline. Transporter may, but is not

obligated to, enter into an OBA to address imbalances at other points on its System. If

an OBA is not in place or the imbalance is beyond the terms of the OBA, Shippers are

responsible for conforming their takes at Delivery Points with their deliveries to

Transporter at Receipt Points each day. Transporter has no obligation to deliver for the

account of a Shipper more volumes of Gas than Transporter has received for the account of

the Shipper or to accept for the account of the Shipper more volumes of Gas than are

being delivered for the account of the Shipper on any day.

13.2 Daily Imbalances

13.2.1 Each Shipper is responsible for balancing the receipts and deliveries of its

agreement(s) on a daily basis. It shall be Shipper’s responsibility, whether or

not delegated to an agent, to cause Gas to be delivered to Transporter as

scheduled at the receipt point(s) and cause Gas to be taken from Transporter at

the delivery point(s) in accordance with the applicable scheduled quantities.

13.2.2 If a Shipper has created an imbalance by failing to conform its receipts to

deliveries, then Transporter, after notification to Shipper, may require Shipper

to nominate, within the same gas day, to clear such imbalance Payback Quantities

or to cash-out any such imbalance in accordance with the downstream pipeline’s

FERC Gas Tariff or OBA with Transporter. Transporter may require Shipper to

nominate, confirm and schedule Payback Quantities to clear an imbalance using a

uniform hourly rate of flow. If necessary for operational purposes or to avoid

cash-out penalties, Transporter may adjust scheduled volumes to match daily

flows.