<PAGE>

                                                                   EXHIBIT 10.33

                                    ENGAGE

October 7, 1999
Via Telecopy

Cascade Natural Gas Corporation
222 Fairview Avenue North
Seattle, Washington 98109-5312

Attn:    Mr. King Oberg
         Vice-President, Gas Supply

Dear King:

Re:      Jackson Prairie Storage Service

This letter outlines the terms and conditions under which Engage Energy Canada,
L.P. ("Engage") would be prepared to purchase storage services from Cascade
Natural Gas ("Cascade") for the upcoming contract year.

Term:                    November 1, 1999, through October 31, 2000

Volume:                  Inventory:                        480,000 MMBtu
                         Withdrawal:      Firm             15,000 MMBtutday
                                          Best efforts     5,533 MMBtu/day

Price:                   Unconditional, up-front payment of $ < * >
                         (est. < * > % of total demand and capacity demand
                         charges).

Revenue Sharing:         < * > % over the term of the agreement. The
                         Revenue Sharing plan will be based solely upon
                         Secondary Call volumes and replacements, and not
                         applicable to the 15 days maximum of Engage Firm Call
                         volumes and replacements. All withdrawals and
                         replacements made by Engage shall be recorded
                         separately from all other Engage business and will be
                         subject to audit by Cascade upon request.

Firm Call:               Engage shall have the first right to call on a maximum
                         of 10,000 MMBtu/day from Cascade, not more that 5 days
                         per month, or more than 15 days over the Firm Call
                         Period (November 1, 1999, through March 31, 2000). For
                         volumes specified as Firm Call Cascade shall be
                         obligated to deliver one hundred (100%) percent of the
                         requested quantity. Similarly, Engage shall be
                         obligated  to take all volumes specified as Firm Call
                         volumes. Further, on the days in which Engage nominates
                         Firm Call volumes, Engage will not request best efforts
                         volumes.

                          Engage Energy Canada, L.P. 1100, 421 7th Ave. S.W,
                                   Calgary, Alberta, Canada T2P 4K9
                               Phone: (403) 297-0333 Fax: (403) 269-5909

< * > = Redacted

<PAGE>

                                                            Cascade Natural Gas
                                                                October 7, 1999
                                                                         Page 2

Secondary Call:           Engage shall have the ability to call on a maximum of
                          15,000 MMBtu/day (firm withdrawal quantity) and up to
                          5,533 MMBtu/day (best efforts quantity) from Cascade
                          over the period. Engage recognizes that Cascade has
                          the first right to call on these volumes, and provides
                          the Secondary Call to Engage on a best-efforts basis
                          only.

Transportation:           For all Firm Call volumes, Engage will have the first
                          right to request delivery of Jackson Prairie
                          withdrawal volumes under Cascade's TF-2
                          transportation. Engage will reimburse Cascade for all
                          TF-2 commodity charges incurred during the periods in
                          which Engage utilizes, such transportation. Engage
                          may also elect to transport Firm Call volumes under
                          its TF-1 service.

                          For all Secondary Call volumes, Engage may request
                          on a best efforts basis delivery of Jackson
                          Prairie withdrawal volumes under Cascade's TF-2
                          transportation. Engage will be reimbursed by Cascade
                          for all TF-2 commodity charges incurred during the
                          periods in which Engage utilizes such
                          transportation. Engage may also elect to transport
                          Secondary Call volumes under its TF-1 service.

                          Engage recognizes that Cascade's TF-2 transportation
                          is limited in volume to the equivalent of 1
                          withdrawal cycle (480,000 MM8tu total), and once
                          utilized is no longer available until the next
                          storage period (November 1, 2000, through October
                          31, 2001).

Replacements:             Engage will replace all volumes withdrawn prior to
                          September 30, 2000. All costs associated with the
                          volume replacement will be Engage's responsibility.

We hope this proposal will meet with your approval. This offer is open for
acceptance until the close of business on October 8, 1999. Following this date,
the proposals contained herein will be deemed to be expired. If you have any
questions, please contact me at (503) 471-1333.


Yours truly,

ENGAGE ENERGY CANADA, L.P.

Fred M. Scott, P.Eng.
Director, Business Development

Agreed to and accepted to this 7th day of October 1999.