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. 62 Original Sheet No. 62

GENERAL TERMS AND CONDITIONS

(Continued)

8.8. Shipper Prioritization of Nominated Quantities – If Shipper elects to

nominate quantities of Gas to be received by Transporter from one or more

upstream parties at one or more Receipt Points for delivery by Transporter

to one or more downstream parties at one or more Delivery Points for the

account of Shipper, Shipper shall provide the priority, method, and extent

to which each nominated receipt quantity from a particular upstream party at

a particular Receipt Point should be reduced in the event that any

downstream Operator verifies and confirms deliveries that are less than the

Shipper’s nominated deliveries, or in the event that, due to Transporter’s

allocation of Available Capacity for Transportation services, all nominated

receipts cannot be scheduled. Likewise, if Shipper elects to nominate

quantities of Gas to be delivered by Transporter to one or more downstream

parties at one or more Delivery Points for the account of Shipper, Shipper

shall provide the priority, method, and extent to which each nominated

delivery quantity to a particular downstream party at a particular Delivery

Point should be reduced in the event that any upstream Operator verifies and

confirms receipts that are less than the Shipper’s nominated receipts, or in

the event that, due to Transporter’s allocation of Available Capacity for

Transportation services, all nomination deliveries cannot be scheduled.

8.8.1. Shipper prioritization of nominated quantities must be consistent

with the terms of this Tariff and such prioritization will be

honored to the extent that Transporter reasonably determines such

prioritization is operationally feasible.

8.9. Delegation of Nomination Authority to Agent – A Shipper may delegate to any

third party the responsibility for submitting nominations and receiving

confirmations or performing other administrative duties under any effective

FT or IT Agreement, subject to the following conditions:

8.9.1. Any designation of a third party as agent, or any change in such

designation, must be provided in writing to Transporter at least two

(2) Business Days prior to the requested effective date of the

designation.