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Exhibit 10.16    
  

	[CASCADE NATURAL GAS LOGO]	 	PURCHASE AUTHORIZATION
	

 	
 	

Date:	
 	
4/25/01                    2:00 p.m.
	 	 	

	

 	
 	

Sempra — Damon Suter

	 	 	("Seller")	 	Fax: (714) 430-9210
	
Cascade Natural Gas Corporation

("Buyer")	
 	

 	
 	

 

By
this Purchase Authorization and subject to the additional terms and conditions contained in the base Gas Purchase Agreement between Buyer and Seller, Buyer agrees to purchase and receive natural
gas on a firm basis under the following terms and conditions: 

	1. Buyer:	 	Cascade Natural Gas Corporation

	

2. Seller:	
 	
Sempra — Damon Suter
    Phone: (714) 241-1500
	

3. Price:	
 	

[**]
	

4. Daily Contract Quantity:	
 	
As per Attached Schedule

	

5. Period of Delivery:	
 	
October 1, 2001 through September 30, 2004

	

6. Pipeline Transporter:	
 	
WGPW

	

7. Delivery Point:	
 	
Sumas and Rockies (South of Green River)

	

8. Load Factor	
 	
100%

	

9. Special Terms	
 	

  

	

 	
 	

  

The
above terms and conditions set out the verbal agreement reached between Buyer and Seller. Please return a signed copy of this Purchase Authorization, by Fax at (206) 624-7215, within twenty-four
hours of receipt. An executed copy of this Purchase Authorization verifies your acceptance of the terms and conditions of this Purchase Authorization and the underlying Gas Purchase Agreement between
Buyer and Seller. 

If
you have questions or concerns regarding this Purchase Authorization, please contact Cascade's Director, Gas Supply at (206) 381-6829. Any dispute of these terms must be directed to Director, Gas
Supply at FAX # (206) 624-7215 within twenty-four hours of receipt. 

	AGREED TO AND ACCEPTED:	 	AGREED TO AND ACCEPTED:
	 	 	 
	 	 	 
	
	 	

	For: Cascade Natural Gas Corporation	 	 
	("Buyer")	 	For:
	 	 	

	 	 	("Seller")

[**] = Confidential
information 

SEMPRA Energy

58 Commerce Road, Stamford, CT 06902. Main Phone: (203) 355-5000. Main Fax: (203) 355-5001  

26-Apr-01

	To:	CASCADE NATURAL GAS CORP.
	Attn:	Natural Gas Confirmation Dept.
	Re:	SEMPRA Contract Number 9192580

We are pleased to confirm the agreement of April 25, 2001 between SEMPRA ENERGY TRADING CORP. ["SEMPRA"] and CASCADE NATURAL GAS CORP.
["Counterpart"] subject to the terms and
conditions of The Natural Gas Purchase and Sale Agreement ["Master Agreement"] and any Margin Agreement, between SEMPRA AND Counterpart. 

1.  Buyer:
Counterpart 

2.  Seller:
SEMPRA 

3.  Type
Of Transaction: Firm 

4.  Contract
Quantity:

Part One:

[A] 10,000 MMBTU PER DAY

[B] 5,000 MMBTU PER DAY

[C] 10,000 MMBTU PER DAY

[D] 5,000 MMBTU PER DAY

[E] 10,000 MMBTU PER DAY

[F] 5,000 MMBTU PER DAY 

Part
Two: 

[A]
10,000 MMBTU PER DAY

[B] 15,000 MMBTU PER DAY

[C] 10,000 MMBTU PER DAY

[D] 5,000 MMBTU PER DAY

[E] 10,000 MMBTU PER DAY

[F] 15,000 MMBTU PER DAY

[G] 10,000 MMBTU PER DAY

[H] 5,000 MMBTU PER DAY

[I] 10,000 MMBTU PER DAY

[J] 15,000 MMBTU PER DAY

[K] 10,000 MMBTU PER DAY

[L] 5,000 MMBTU PER DAY 

5.  Delivery
Period:

Part One:

[A] October 1, 2001 through and including April 30, 2002

[B] May 1, 2002 through and including September 30, 2002

[C] October 1, 2002 through and including April 30, 2003

[D] May 1, 2003 through and including September 30, 2003

[E] October 1, 2003 through and including April 30, 2004

[F] May 1, 2004 through and including September 30, 2004 

Part
Two:

[A] October 1, 2001 through and including October 31, 2001

[B] November 1, 2001 through and including March 31, 2002

[C] April 1, 2002 through and including April 30, 2002

[D] May 1, 2002 through and including September 30, 2002

[E] October 1, 2002 through and including October 31, 2002

[F] November 1, 2002 through and including March 31, 2003

[G] April 1, 2003 through and including April 30, 2003

[H] May 1, 2003 through and including September 30, 2003

[I] October 1, 2003 through and including October 31, 2003

[J] November 1, 2003 through and including March 31, 2004

[K] April 1, 2004 through and including April 30, 2004

[L] May 1, 2004 through and including September 30, 2004 

6.  Delivery
Point:

Part One: NORTHWEST PIPELINE CORP., MAINLINE [SOUTH OF GREEN RIVER]

Part Two: SUMAS 

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Exhibit 10.16Prepared by MERRILL CORPORATION

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Exhibit 10.21.1    
  

 
 

AMENDED
  EXHIBIT "A"
  
    To The
  
    GAS PURCHASE CONTRACT
  
    As Of: October 1, 1994
  
    Between
  
    CASCADE NATURAL GAS CORPORATION ("BUYER")
  
    and
  

   IGI RESOURCES, INC. ("SELLER")    
  

Effective
Date of this Exhibit "A":  October 1, 2001 

Ending
Date of this Exhibit "A":  March 31, 2002 

	DELIVERY POINT	 	As defined in Section 1.01(g) of the Contract noted above
	 	 	 
	MAXIMUM DAILY CONTRACT QUANTITY(MMBtu)	 	7,446
	 	 	 
	DELIVERY POINT SELLING PRICE	 	1/

	1.
	The
Delivery Point Selling Price shall be equal to four dollars and sixty eight cents [*]U.S. dry) per MMBtu at AECO-C Hub plus the actual cost
of firm NOVA re-delivery service and firm ANG receipt and re-delivery service plus any applicable allowance for fuel-in-kind associated with such
services. 

[*] = Confidential Information

	 	 	"BUYER"

CASCADE NATURAL GAS CORPORATION
	 	 	 	 	 
	 	 	By:	 	/s/ King Oberg

	 	 	Name:	 	King Oberg

	 	 	Title:	 	Vice President, Gas Supply

	 	 	 	 	 
	 	 	 	 	 
	 	 	"SELLER"

IGI RESOURCES, INC.
	 	 	 	 	 
	 	 	By:	 	/s/ Randy Schultz

	 	 	Name:	 	Randy Schultz

	 	 	Title:	 	President

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Exhibit 10.21.1

AMENDED EXHIBIT "A" To The GAS PURCHASE CONTRACT As Of: October 1, 1994 Between CASCADE NATURAL GAS CORPORATION ("BUYER") and IGI RESOURCES, INC. ("SELLER")Prepared by MERRILL CORPORATION

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Exhibit 10.21.2    
  

 
 

AMENDED
  EXHIBIT "A"
  
    To The
  
    GAS PURCHASE CONTRACT
  
    As Of: October 1, 1994
  
    Between
  
    CASCADE NATURAL GAS CORPORATION ("BUYER")
  
    and
  

   IGI RESOURCES, INC. ("SELLER")    
  

Effective
Date of this Exhibit "A":  October 1, 2002 

Ending
Date of this Exhibit "A":  March 31, 2003 

	DELIVERY POINT	 	As defined in Section 1.01(g) of the Contract noted above
	 	 	 
	MAXIMUM DAILY CONTRACT QUANTITY(MMBtu)	 	7,446
	 	 	 
	DELIVERY POINT SELLING PRICE	 	1/

	1.
	The
Delivery Point Selling Price shall be equal to four dollars and sixty eight cents ($[*]U.S. dry) per MMBtu at AECO-C Hub plus the actual cost
of firm NOVA re-delivery service and firm ANG receipt and re-delivery service plus any applicable allowance for fuel-in-kind associated with such
services. 

[*] = Confidential Information

	 	 	"BUYER"

CASCADE NATURAL GAS CORPORATION
	 	 	 	 	 
	 	 	By:	 	/s/ King Oberg

	 	 	Name:	 	King Oberg

	 	 	Title:	 	Vice President, Gas Supply

	 	 	 	 	 
	 	 	 	 	 
	 	 	"SELLER"

IGI RESOURCES, INC.
	 	 	 	 	 
	 	 	By:	 	/s/ Randy Schultz

	 	 	Name:	 	Randy Schultz

	 	 	Title:	 	President

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Exhibit 10.21.2

AMENDED EXHIBIT "A" To The GAS PURCHASE CONTRACT As Of: October 1, 1994 Between CASCADE NATURAL GAS CORPORATION ("BUYER") and IGI RESOURCES, INC. ("SELLER")Prepared by MERRILL CORPORATION

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Exhibit 10.21.3    
  

 
 

AMENDED
  EXHIBIT "A"
  
    To The
  
    GAS PURCHASE CONTRACT
  
    As Of: October 1, 1994
  
    Between
  
    CASCADE NATURAL GAS CORPORATION ("BUYER")
  
    and
  

   IGI RESOURCES, INC. ("SELLER")    
  

Effective
Date of this Exhibit "A":  October 1, 2003 

Ending
Date of this Exhibit "A":  March 31, 2004 

	DELIVERY POINT	 	As defined in Section 1.01(g) of the Contract noted above
	 	 	 
	MAXIMUM DAILY CONTRACT QUANTITY(MMBtu)	 	7,446
	 	 	 
	DELIVERY POINT SELLING PRICE	 	1/

	1.
	The
Delivery Point Selling Price shall be equal to four dollars and sixty eight cents [*]U.S. dry) per MMBtu at AECO-C Hub plus the actual cost
of firm NOVA re-delivery service and firm ANG receipt and re-delivery service plus any applicable allowance for fuel-in-kind associated with such
services. 

[*] = Confidential Information

	 	 	"BUYER"

CASCADE NATURAL GAS CORPORATION
	 	 	 	 	 
	 	 	By:	 	/s/ King Oberg

	 	 	Name:	 	King Oberg

	 	 	Title:	 	Vice President, Gas Supply

	 	 	 	 	 
	 	 	 	 	 
	 	 	"SELLER"

IGI RESOURCES, INC.
	 	 	 	 	 
	 	 	By:	 	/s/ Randy Schultz

	 	 	Name:	 	Randy Schultz

	 	 	Title:	 	President

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Exhibit 10.21.3

AMENDED EXHIBIT "A" To The GAS PURCHASE CONTRACT As Of: October 1, 1994 Between CASCADE NATURAL GAS CORPORATION ("BUYER") and IGI RESOURCES, INC. ("SELLER")Prepared by MERRILL CORPORATION

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Exhibit 10.22.1    
  

November 20,
2001 

Fax No. (206) 624-7215  

Cascade Natural Gas Corporation

222 Fairview Avenue North

Seattle, Washington

98109 

Attention:  Pattie Grable

Dear
Pattie: 

	Re:	 	Gas Transaction Confirmation ("GTC") dated November 20, 2001 between

Cascade Natural Gas Corporation and Engage Energy Canada, L.P.
 Supercedes GTC dated May 7, 2001

As
per the terms of the attached GTC (Section 2 iii) C), dated November 20, 2001, Cascade Natural Gas Corporation has unwound a portion of the volumes (10% for the period
November 1, 2001 to March 31, 2002, and 15% for the period April 1, 2002 to October 31, 2002) due to being overhedged. Subsequently, the price applicable for the period
November 1, 2001 to March 31, 2002 shall be equal to $[*] US/MMBtu, and for the period April 1, 2002 to October 31, 2002, shall be equal to
$[*] US/MMBtu. 

If
you are in agreement with the terms, please indicate your acceptance by signing both copies of this letter in the space provided below and return one copy to Engage for our files. Please note our
offices moved in July and our new address is as shown below. If you have any questions, please give me a call at (403) 699-1036. 

Yours
truly, 

	ENGAGE ENERGY CANADA, L.P.	 	 
	 	 	 
	 	 	 
	

Kevin Turchanski,

Vice President, Natural Gas

West Region	 	 
	 	 	 
	Att.	 	 

Accepted and Agreed to this      day of         , 2001.  

	CASCADE NATURAL GAS CORPORATION	 	 
	 	 	 	 	 
	Per:	 	 	 	 
	 	 	
	 	 
	 	 	 	 	 
	Title:	 	 	 	 
	 	 	
	 	 

[*] = Confidential Information

Engage Energy Canada, L.P., 2200, 425 - 1st Street S.W., Calgary, Alberta, Canada T2P 3L8

Telephone: (403) 699-1000 Fax: (403) 269-5909 

 
 

REVISED GAS TRANSACTION CONFIRMATION
  Supercedes GTC dated May 7, 2001    
  

Contract #1872  

	1.
 
	 	BUYER:
 
	 	SELLER:
 
	 	GAS TRANS. AG.

EFF. DATE:
 
	 	DATE FORM

DELIVERED:
 

	 	 	Cascade Natural Gas Corporation	 	Engage Energy Canada, L.P.	 	July 1, 1994	 	November 20, 2001

2. DETAILS OF TRANSACTIONS:

	Trans.

No
	 	Start

Date/Time
	 	End

Date/Time
	 	Quantity/

day

(MMBtu)
	 	Price

(Cdn$)

(See 3. below)
	 	Qual. of Service

(Int, Firm or EFP)
	 	Del. Point
	 	Del.

Pipe
	 	Rec.

Pipe

	1)	 	See

Section 3	 	See

Section 3	 	27,037

MMBtu	 	See Section 3	 	Firm	 	Kingsgate	 	WEI	 	WEI

3. Special Provisions Including Price Details (if any): 

	1)
	Commodity Price of Original August 17, 1994 Contract.

Price as per Amending Agreement dated October 2, 2001 as follows: 
	a.
	The
Gas Commodity Price to be paid for gas delivered each month during the period commencing on November 1, 2001 and expiring on October 31, 2002 shall be calculated as a percentage
price determined under Subsection c below, based upon a weighted average of the following published prices (the "Index Price"):

	(i)
	the
"Rocky Mountain" designated supply source into the Northwest pipeline system, as that price is
provided in the publication entitled, "Inside F.E.R.C.'s Gas Market Report" in the table entitled, "Prices of Spot Gas Delivered
to Pipelines.....(per MMBtu dry), under the "Northwest Pipeline Corp." entry multiplied by 26%; and

	(ii)
	the
"Canadian Border" designated supply source into the Northwest pipeline system, as that price
is provided in the publication entitled, "Inside F.E.R.C.'s Gas Market Report" in the table entitled, "Prices of Spot Gas
Delivered to Pipelines.....(per MMBtu dry), under the "Northwest Pipeline Corp" entry multiplied by 35%; and

	(iii)
	the
"AECO "C" & N.I.T. One-Month Spot" price as published by the
"Canadian Gas Price Reporter" in the table entitled, "Canadian Natural Gas Supply Prices" under the
column entitled "Avg" in U.S$/MMBtu multiplied by 39%. 

	b.
	The
reference publication issue to determine the Gas Commodity Price for a month shall be the first issue which is published after the first day of the month.

	c.
	The
percentage of the Index Price shall be as follows:

November 1, 2001 March 31, 2002 — 90%

April 1, 2002 — October 31, 2002 — 85% 

	2)
	Price Conversion:
	i)
	November 1,
2001 — October 31, 2004*

Price conversion transacted on April 3 and 4th, 2001 for the entire 27,037 MMBtu/Day

Price = U.S$4.66 per MMBtu 

*The application as per 1)c. will equate to the following:

For the period November 1, 2001 to March 2, 2002 = U.S$[*]per MMBtu

For the period April 1, 2002 to October 31, 2002 = U.S$[*]per MMBtu

	ii)
	The
Parties acknowledge and agree that the fixed price conversion hedge set out above is and will remain in full force and effect, even if the Index
Price percentage components 

set
out in Section 1)a. above and the percentage of the Index Price as set out in Section 1)c. are renegotiated. 

	iii)
	If:

	A)
	at
any time prior to October 31, 2004;

	B)
	through
annual price renegotiations with Pan-Alberta Gas and Cascade under the original August 17, 1994 Amended and Restated Natural Gas Sales Agreement, there are changes to
the percentages to the individual percentage components comprising the Index Price or the Index Price otherwise is amended in any material fashion; and

	C)
	the
changes or amendments result in the Buyer being overhedged or underhedged based on the fixed price of US$[*]per MMBtu set out in Subsection 2 i) above; 

then
Seller will use commercially reasonable efforts to implement hedge changes consistent with the Index Price changes or amendments. Notwithstanding such efforts, Buyer will remain liable for any
losses or gains resulting from Buyer being overhedged or underhedged due to the Index Price changes or amendments. 

	iv)
	If
 price renegotiations are commenced between Buyer and Seller and between Seller and PanAlberta in accordance with the August 17, 1994 Agreement then Seller shall use commercially
reasonable efforts to ensure any such Index Price changes or amendments do not result in Buyer being underhedged or overhedged in accordance with the above.

	v)
	In
the event:

	A)
	Seller's
credit rating as determined by Standard and Poors falls below "BBB"; or

	B)
	the
aggregate mark to market valuation for all forms of energy related agreements, arrangements and transactions between Buyer and Seller (as such valuation is determined by Seller
acting reasonably) exceeds US $35 million; 

then
Buyer will provide to Seller a Letter of Credit in an amount determined by Seller acting reasonably to securitize Seller's calculated net exposure to Buyer. 

	3)
	Load Factor Commitment
	i)
	All
price conversion volumes shall be purchased and sold on a Firm, 100% load factor basis for the entire Quantity/day. 

4. ADDRESSES, OPERATIONS AND BILLINGS AND PAYMENT INFORMATION:

	Engage Energy Canada, L.P.	 	Cascade Natural Gas Corporation ("Customer")
	1100, 421-7th Avenue S.W.	 	222 Fairview Avenue North
	Calgary, Alberta	 	Seattle WA 98109
	Canada T2P 4K9	 	U.S.A.
	 	 	 
	Marketing Representative Name:

Kevin Turchanski	 	Marketing Representative:

Pattie Grable
	Phone: (403) 699-1034	 	Phone: (206) 381-6829
	Fax: (403) 221-8643	 	Fax: (206) 624-7215
	 	 	 
	Accounting Contact: Trevor Gibb	 	Accounting Contact:
	Phone: (403) 699-1039	 	Phone: (206)
	Fax: (403) 221-8643	 	Fax: (206)
	 	 	 
	Operations Contact: Shelley Langdon	 	Operations Contact:
	Phone: (403) 699-1050	 	Phone: (206)
	Fax: (403) 221-8643	 	Fax: (206)
	

Wire Transfer Acct:	
 	

Wire Transfer Acct:

	5.	 	(a)	 	The above are the essential binding terms of the transaction in question. If a formal master physical agreement is in effect between the parties, then the above confirmation terms are subject to that agreement. In the
event of any conflict between this transaction and the terms of the formal agreement, the terms above prevail. If no formal agreement exists, then the parties will finalize and sign one, failing which this transaction remains binding on the parties.
Upon finalizing that agreement, the above transaction will form a part of, and be subject to, that formal agreement.
	

 	
 	

(b)	
 	

If the customer notes any discrepancy between the provisions as orally agreed to and the above, please notify Engage within two (2) Business Days of delivery of this form. After that, all provisions will be presumed to be correct.
	

 	
 	

(c)	
 	

For "Firm" Quality of Service, the Replacement Market Price will be equal to the published index price appearing on the next immediate Business Day after the day or days of the Basic Performance Default.

[*] = Confidential Information

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Exhibit 10.22.1

REVISED GAS TRANSACTION CONFIRMATION Supercedes GTC dated May 7, 2001

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