SPECIAL CONTRACT FOR NATURAL GAS TRANSPORTATION SERVICE

Exhibit 10.72

SPECIAL CONTRACT FOR

NATURAL GAS TRANSPORTATION SERVICE

Whereas, ENSTAR Natural Gas Company (“Company”), and Chugach Electric Association, Inc. (“Customer”) desire to enter into a contract for the transportation of Customer’s natural gas; and

Whereas, the Customer is certificated to provide electric public utility service in and around Anchorage, Alaska; and

Whereas, since November 2010, the Company has transported natural gas to the Customer’s Beluga Power Plant under the Special Contract, signed on October 15^th, 2010; and

Whereas, the full term of the Special Contract runs from November 15, 2010 through October 31, 2011; and

Whereas, the Customer has a continuous need for the transportation of Gas to supply its Beluga Power Plant; and

Whereas, due to the changes in Cook Inlet natural gas production since 2008, the Company is no longer able to provide VLFT service to the Beluga Power Plant at the level desired by the Customer year round on a firm basis; and

Whereas, the Customer has asked the Company whether it can provide limited firm transportation service beginning November 1, 2011, through March 31, 2012, and firm transportation service from April 1, 2012 through October 31, 2012; and

Whereas, because of the urgent and temporary situation facing the Customer, the Company is willing to provide transportation service on a limited firm basis for the period commencing on November 1, 2011 and ending on March 31, 2012 (“Period I”); and

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Whereas, the Company is further willing to provide transportation service on a firm basis on April 1, 2012 and ending on October 31, 2012 (“Period II”); and

Whereas, by doing so, the Company is not undertaking any express or implied commitment to the Customer beyond the term of this Special Contract, and is not agreeing that it has any obligation to serve the Customer;

Be it Resolved that due to the unique circumstances of the Customer’s short-term transportation service requirements qualify it for a special contract; and

Further Resolved that the Company is willing to do what it can to support the Customer’s needs under the terms stated below, provided that it does not interfere with its ability to meet other, existing firm delivery obligations.

In consideration of the covenants and conditions in this Special Contract, the parties agree as follows:

ARTICLE I

PARTIES

1.1 The parties to this contract are ENSTAR Natural Gas Company, a division of SEMCO Energy, Inc. (“Company”) and Chugach Electric Association, Inc. (“Customer”).

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ARTICLE II

TERM

2.1.1 The full term of this Special Contract shall be from November 1, 2011 through October 31, 2012. Any extension of term will be by mutual agreement of both parties, in writing, at least 90 days prior to the expiration date of the full term.

2.1.2 Period l (Limited Firm Transportation Service) shall be from November 1, 2011 through March 31, 2012.

2.1.3 Period lI (Firm Transportation Service) shall be from April 1, 2012 through October 31, 2012.

ARTICLE Ill

MODIFIED TARIFF PROVISIONS

The Company agrees to transport up to a maximum of 20,000 thousand cubic feet per day (Mcf/d) during Period I (Limited Firm Transportation Service) and Period II (Firm Transportation Service). This is the Contract Peak Demand. To assist the Company in providing thls service, the Customer shall provide the Company with the forecasts and nominations required by Sections 1605c and 1605d of the Company’s Tariff, including but not limited to the Monthly and Daily nominations required by Sections 1605d(1) and 1605d(3), and adhere to the balancing provisions as set out in Section 1605e.

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In both Period I and Period II, in consideration of the Services provided by the Company to the Customer, the Customer shall pay the Company the rates in the Company’s Tariff Schedule VLFT (Sections 2150b, 2150c, and 2150d) with the exception of the monthly demand charge as set forth and defined in Section 2150b. The Monthly Demand Charge under this Special Contract will be $40,000. The Monthly Demand Charge set forth in the previous sentence is a discount from the firm charge multiplied by the Contracted Peak Demand. The Customer will also reimburse the Company for all tariffed charges incurred to transport gas on the west side of Cook Inlet by the Company to provide Services under this Special Contract. The terms of Section 2150a of the Company’s Tariff shall also apply, except that a separate Very Large Firm Transportation Service Agreement is not required.

3.3.2 If the Company is unable to deliver the Contracted Peak Demand, the Customer agrees to waive reimbursement from the Company for any Interruption

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Expense it might incur as defined by the Company’s Tariff Section 1205 (Interruption Cost) for Period I. The pricing agreed to in this Special Contract, which covers the full period of the agreement (Periods I and II), is structured with a price discount to acknowledge Limited Firm Transportation Service provided by the Company during Period I.

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a. 12:00 AM to 6:00AM

b. 6:00AM to 12:00 PM

c. 12:00 PM to 6:00 PM

d. 6:00PM to 11:59.59 PM

The Customer will provide estimated hourly set points for Meter 8107 and the Company will apply its best efforts to follow.

The Customer will nominate gas based on an average load calculation for each intra-day nomination period. The Company and Customer understand that Customer deliveries will vary from the average based on actual (instantaneous) generation requirements.

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ARTICLE IV

DELIVERY/RECEIPT POINTS

The Delivery Point for this Special Contract is the Customer’s Beluga Power Plant at the Company’s Metering Station #8253, Meter 8107.

Period I Receipt Points are as follows:

ConocoPhillips Company (“COP”) and ConocoPhillips Alaska, Inc. (“CPAI”)

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b. Interconnection of the Beluga River Unit- APC Beluga pipelines: Station

B601. Suppliers and Supplier contact information:

ConocoPhillips Company (“COP”) and ConocoPhillips Alaska, Inc. (“CPAI”)

Period 2 Receipt Points are as follows:

ConocoPhillips Company (“COP”) and ConocoPhillips Alaska, Inc. (“CPAI”)

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ARTICLE V

APPLICABILITY OF THE COMPANY’S TARIFF

Except as expressly modified by this Special Contract, all of the terms and conditions of the Company’s Tariff (RCA No. 4) shall apply to the Services provided by the Company to the Customer under this Special Contract, including without limitation Section 1200 (Interruption). Further, due to the anticipated average and peak daily demand of the Customer, the following Sections of the Company’s Transportation provisions will apply: Section 1605c (Forecasts), Section 1605d (Nominations), Section 1605e (Balancing), Section1605f (Pressure}, 1605g (Measuring Stations), Section 1605h (Measurement), and Section 1605j (Credit and Billing).

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With respect to Balancing (Section 1605e) the Customer’s daily nominations will be compared to the actual volumes delivered to the Customer for the purposes of applying the Daily Balancing Tolerances and computing Over or Under Supply (Sections 1605e(3) and 1605e(4)).

The Customer acknowledges that it has a copy of the Company’s Tariff RCA No. 4 and is familiar with its provisions.

ARTICLE VI

RCA APPROVAL

The Parties understand that this Special Contract does not take effect without the prior approval of the Regulatory Commission of Alaska and is, at all times, subject to revisions by the Commission. This Special Contract shall be effective on the date of a final order by the RCA approving this Special Contract.

In the event that revisions to this Special Contract are required by the RCA or any other governmental body acting within its jurisdiction and the revisions are not acceptable to either party, either party may terminate this Special Contract by giving notice under this Article 6.2 within thirty (30) days of receipt of the order requiring the revisions.

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ARTICLE VII

ADDRESSES

All notices, except as provided for nominations or billings, shall be given in writing at the address set forth below. Notice shall be deemed to have been given when received by the Company or the Customer at those addresses.

For Transportation Nominations from the Customer, Scheduling and Day to Day Operations:

For Payments:

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For all other Notices:

ENSTAR Natural Gas Company

For Scheduling and Day to Day Operations:

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ARTICLE VIII

OTHER TERMS

The Customer will indemnify, defend and hold the Company harmless against any and all claims by other Cook Inlet purchasers or producers concerning the purchasing of Gas or the priority of Gas taken under this Special Contract.

By making this commitment to transport Gas to the Customer, the Company is not agreeing that it has any obligation, beyond the term of this Special Contract, to transport Gas to the Customer’s Beluga Power Plant.

This Special Contract is contingent upon the Customer securing sufficient commitment of Gas from its suppliers and delivery of such gas to the Receipt Points.

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This agreement will be submitted to the Board of Directors of Chugach for its approval and is subject to termination by Chugach if such board approval is not received by October 31, 2011. If this Agreement is terminated under this Article 8.4, Chugach will provide notification to the Company of such termination no later than November 1, 2011.

ARTICLE IX

MISCELLANEOUS

This Special Contract shall be binding upon and inure to the benefit of the legal representatives, successors and assigns of the parties. Except as provided below, neither party may assign its rights and obligations under this Special Contract without first obtaining the written consent of the other. Consent is not required if all or substantially all of the assets of the Company or the Customer are acquired by another person or the Company or the Customer is merged, consolidated or reorganized with another person, provided that the assignee assumes in writing the assignor’s obligations under this Special Contract. Nothing contained in this Article shall prevent either party from pledging or mortgaging its rights under the Special Contract for security of its indebtedness.

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The parties recognize that this Special Contract is the product of the joint efforts of the parties and agree that it shall be construed according to its plain meaning and shall not be construed against either party as drafter.

This Special Contract, including Exhibits A through C and the Company’s Tariff, constitutes the entire agreement and understanding between the parties concerning the subject matter of this transaction, and all prior agreements, understandings and representations, whether oral or written, concerning this subject matter are superseded by this written Special Contract. No amendment to this Special Contract shall be binding on either party until reduced to writing and signed by the parties.

The headings throughout this Special Contract are for reference purposes only and shall not be considered in interpreting this Special Contract.

Neither party shall have any liability to the other for incidental or consequential damages resulting from this Special Contract.

The parties understand and agree that no person or entity is an intended third party beneficiary of this Special Contract.

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IN WITNESS WHEREOF, the parties have executed this Special Contract in two (2) originals.

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Exhibit A

Events That Could Cause Interruption

a. Severe cold (typified by loss of line pressure for 3 to 5 days).

i. APC line pressure indicators.

b. Continuous cold (typified by loss of line pressure over time (5 to 7 days)).

i. APC line pressure indicators.

a. Low field production from west side suppliers.

Event management:

ENSTAR will provide reasonable notification to CEA of possible transportation constraint(s) due to a weather event and will exercise commercially reasonable efforts to reduce services under this Special Contract gradually.

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