MarkWest Pioneer, L.L.C.

Original Volume No. 1

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

Original Sheet No. 77 Original Sheet No. 77

GENERAL TERMS AND CONDITIONS

(Continued)

19. BILLING AND PAYMENT

19.1. Transporter shall render invoices on or before the tenth day of each month

for all Gas delivered in the preceding monthly billing period. Invoices may

be rendered to Shipper by mail, electronically or facsimile. When

information necessary for billing purposes is in the control of Shipper,

such information shall be delivered to Transporter by Shipper on or before

the fifth day of the month following the month in which service was

provided.

19.2. Shipper shall pay to Transporter at its designated office on or before the

fifteenth day of each month for the Gas delivered by Transporter during the

preceding month and invoices by Transporter; provided, however, Shipper’s

payment shall never be due until ten (10) days from the postmark, e-mail

notification or facsimile confirmation date of Transporter’s invoice.

19.3. Should Shipper fail to pay all of the amount of any invoice as herein

provided when such amount is due, Shipper shall pay a Charge for Late

Payment. Such Charge for Late Payment shall be determined by multiplying

(a) the unpaid portion of the invoice, by (b) the ratio of the number of

days from the due date to the date of actual payment to 365, and by (c) the

interest rate determined in accordance with Section 154.501(d) of the

Commission’s regulations. If such failure to pay continues for thirty (30)

days after payment is due, Transporter may suspend service; and, if

Transporter has provided Shipper and the Commission with at least thirty

(30) days notice that service will terminate due to the non-payment,

Transporter, in addition to any other remedy it may have under the service

contract, may after application to and authorization by the Commission, if

that authorization is necessary, terminate the service contract; provided

however, that is Shipper in good faith shall dispute the amount of any such

invoice or part thereof and shall pay to Transporter such amounts as it

concedes to be correct in addition to providing such remittance detail and

documentation identifying the basis of the dispute, and at any time within

thirty (30) days after a demand is made by Transporter shall furnish good

and sufficient surety bond or such other mutually agreeable security,