EXHIBIT 10.1 [Canadian Hydrocarbons Marketing Inc. Letterhead] September 1, 1993 Cascade Natural Gas Corporation 222 Fairview Avenue North Seattle, Washington U.S.A. 98109 Attention: Ms. Melissa Whitten Dear Madam: Re: Canadian Hydrocarbons Marketing Inc./Cascade Natural Gas Corporation Natural Gas Purchase Agreement Dated November 1, 1990 Pursuant to Section 7.09 of the above noted agreement, Canadian Hydrocarbons Marketing Inc. ("CHMI") proposes via this letter that the Reserves Standby Fee and Gas Commodity Price be renegotiated for the contract year November 1, 1993 to October 31, 1994. Gas Commodity Price In regard to the Gas Commodity Price, CHMI proposes the following two alternatives for Cascade Natural Gas Corporation's ("Cascade") consideration. Alternative #1 The Gas Commodity Price would be calculated monthly as being [CONFIDENTIAL INFORMATION OMITTED AND FILED SEPARATELY WITH THE COMMISSION] of the Index Price for "Spot Sales" of gas delivered into the Northwest Pipeline Corporation ("NWP") System at Sumas, Washington as quoted in the first publication of each applicable month by the publication Inside F.E.R.C. Natural Gas Market Report plus the Westcoast Motor Fuel Tax. Alternative #2 The Gas Commodity Price would be set at [CONFIDENTIAL INFORMATION OMITTED AND FILED SEPARATELY WITH THE COMMISSION]/MMBtu. Reserves Standby Fee Common to Alternatives #1 and #2, CHMI proposes that the Reserves Standby Fee be rolled over at the existing [CONFIDENTIAL INFORMATION OMITTED AND FILED SEPARATELY WITH THE COMMISSION]/MMBtu. The gas industry is currently experiencing a period of uncertainty and CHMI is cognizant of Cascade's need to moderate the transition in gas prices to its customers. CHMI feels that the foregoing pricing proposal is reasonable and would provide Cascade with supply costs which are competitive and in line with the expected prices to be paid by other customers off the NWP System. If you are in concurrence with the foregoing, please indicate your preference of alternative #1 or #2 in the space provided below and sign both copies of this letter and return both copies to CHMI. Upon execution CHMI will return one copy to Cascade for your files. Yours truly, CANADIAN HYDROCARBONS MARKETING INC. /s/ J.A. Thompson J.A. Thompson Director, Marketing & Supply JAT/sk AGREED AND ACCEPTED TO Alternative #1 this 15th day of October, 1993 CASCADE NATURAL GAS CORPORATION Alternative #2 Per: /s/ King Oberg King Oberg Vice President, Gas Supply AGREED AND ACCEPTED TO this 20th day of October, 1993 CANADIAN HYDROCARBONS MARKETING INC. Per: /s/ D. I. Andrews