Williams Natural Gas Company

Second Revised Volume No. 1

Effective Date: 05/01/1997, Docket: RP97- 67-002, Status: Effective

Third Revised Sheet No. 262 Third Revised Sheet No. 262 : Superseded

Superseding: Second Revised Sheet No. 262

GENERAL TERMS AND CONDITIONS

18. BILLING AND PAYMENTS (Cont'd)

copy any documents that can be properly audited hereunder, and each

party agrees that such copies will be used only for their purposes

hereunder and will not be disclosed to unrelated parties. All bills are

deemed accurate if not challenged within six (6) months of the invoice

date.

Invoices for all gas received or delivered during each billing period

will be prepared on or before the ninth business day after the end of

the production month. The imbalance statement will be rendered prior to

or with the invoice. The term "rendered" shall mean postmarked,

time-stamped and delivered to the designated site. WNG will estimate

missing or late measurement data and treat actual as a prior period

adjustment, with the measuring party providing the estimate. Payment

shall be made to WNG at the location specified on the invoice, within

ten days from the date on the invoice. Shipper shall submit supporting

documentation with any payment. WNG shall apply the payment per the

supporting documentation provided by the Shipper. If the payment

differs from the invoiced amount, remittance detail must be provided.

Shipper shall identify invoice number(s) on all payments. If the

invoice is in dispute, Shipper shall pay the portion not in dispute and

provide documentation identifying the basis for the dispute.

If payment of such invoice is not received by WNG within the time stated

herein, interest thereon shall accrue monthly at the currently effective

rate stated in Section 154.501 of the Federal Energy Regulatory

Commission's Regulations under the Natural Gas Act from the due date

until the date payment is received by WNG. In the event the amount of

the invoice is paid under protest and if it is later determined that an

overcharge has been paid, WNG shall refund the amount of the overcharge

with interest thereon from the date of payment of the overcharge at the

same rate currently charged for late payments.

The time limitation for disputes of allocations shall be six (6) months

from the date of the initial month-end allocation with a three (3) month

rebuttal period. This standard shall not apply in the case of

deliberate omission or misrepresentation or mutual mistake of fact.

Parties' other statutory or contractual rights shall not otherwise be

diminished by this standard.