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                                                         CNG Contract No. 300115

                                                                   EXHIBIT 10.46

                                SERVICE AGREEMENT
                    APPLICABLE TO THE STORAGE OF NATURAL GAS
                     UNDER RATE SCHEDULE GSS (North Summit)

      AGREEMENT made effective as of November 1, 1998, by and between CNG
TRANSMISSION CORPORATION, a Delaware corporation, hereinafter called "Pipeline,"
and COLONIAL GAS COMPANY, a Massachusetts corporation, hereinafter called
"Customer."

      WHEREAS, in conjunction with Article VII of the August 31, 1998
Stipulation and Agreement in Pipeline's Docket Nos. RP97-406-000, et al.,
Pipeline and Customer have agreed to establish an agreement under Pipeline's
Rate Schedule GSS, which will ultimately supplant the "Service Agreement
Applicable To the Storage of Natural Gas Under Rate Schedule GSS-II (Part 284 --
North Summit)" between Pipeline and Customer dated September 1, 1997, commencing
effective as of November 1, 1998.

      WITNESSETH: That in consideration of the mutual covenants herein
contained, the parties hereto agree that Pipeline will store natural gas for
Customer during the term, at the rates and on the terms and conditions
hereinafter provided:

                              Article I. Quantities

      Beginning as of November 1, 1998 and thereafter for the remaining term of
this agreement, Customer agrees to deliver to Pipeline and Pipeline agrees to
receive for storage in Pipeline's underground storage properties, and Pipeline
agrees to inject or cause to be injected into storage for Customer's account,
store, withdraw from storage, and deliver to Customer and Customer agrees to
receive, quantities of natural gas as set forth on Exhibit A. attached hereto.

                                Article II. Rate

      A. For storage service rendered by Pipeline to Customer hereunder,
Customer shall pay Pipeline the maximum rates and charges provided under Rate
Schedule GSS contained in Pipeline's effective FERC Gas Tariff or any effective
superseding rate schedule.

      B. Pipeline shall have the right to propose, file, and make effective with
the FERC or any other body having jurisdiction, revisions to any applicable rate
schedule, or to propose, file, and make effective superseding rate schedules for
the purpose of changing the rate, charges, and other provisions thereof
effective as to Customer; provided, however, that (i) Section 2 of Rate Schedule
GSS "Applicability and Character of Service," (ii) term, (iii) quantities, and
(iv) points of receipt and points of delivery shall not be subject to unilateral
change under this Article. Said rate schedule or superseding rate schedule and
any revisions thereof which shall be filed and made effective shall apply to and
become a part of this Service Agreement. The


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                                                         CNG Contract No. 300115

filing of such changes and revisions to applicable rate schedule shall be
without prejudice to the right of Customer to contest or oppose such filing and
its effectiveness.

      C. The Storage Demand Charge and the Storage Capacity Charge provided in
the aforesaid rate schedule shall commence on November 1, 1998.

                         Article III. Term of Agreement

      Subject to all the terms and conditions herein, this Agreement shall be
effective as of November 1, 1998, and shall continue in effect for a primary
term through and including March 31, 2012, and for subsequent annual terms of
April 1 through March 31 thereafter, until either party terminates this
Agreement by giving written notice to the other at least twenty-four months
prior to the start of an annual term.

                   Article IV. Points of Receipt and Delivery

      The Points of Receipt for Customer's tender of storage injection
quantities, and the Point(s) of Delivery for withdrawals from storage shall be
specified on Exhibit A, attached hereto.

             Article V. Incorporation By Reference of Tariff Provisions

      To the extent not inconsistent with the terms and conditions of this
Agreement, the following provisions of Seller's effective FERC Gas Tariff, and
any revisions thereof that may be made effective hereafter are hereby made
applicable to and a part hereof by reference:

            1. All of the provisions of Rate Schedule GSS, or any effective
superseding rate schedule or otherwise applicable rate schedule; and

            2. All of the provisions of the General Terms and Conditions, as
they may be revised or superseded from time to time.

                            Article VI. Miscellaneous

      A. No change, modification or alteration of this Agreement shall be or
become effective until executed in writing by the parties hereto; provided,
however, that the parties do not intend that this Article VI.A. requires a
further written agreement either prior to the making of any request or filing
permitted under Article II hereof or prior to the effectiveness of such request
or filing after Commission approval, provided further, however, that nothing in
this Agreement shall be deemed to prejudice any position the parties may take as
to whether the request, filing or revision permitted under Article II must be
made under Section 7 or Section 4 of the Natural Gas Act.

      B. Any notice, request or demand provided for in this Agreement, or any
notice which either party may desire to give the other, shall be in writing and
sent to the following addresses:


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                                                         CNG Contract No. 300115

             Pipeline:  CNG Transmission Corporation
                        445 West Main Street
                        Clarksburg, West Virginia 26301
                        Attention: Vice President, Wholesale Marketing
                        Fax: (304) 623-8323

             Customer:  Colonial Gas Company
                        40 Market Street
                        Lowell, Massachusetts 01852
                        Attention: Senior Vice President, Gas Supply
                        Fax: (978) 459-2314

or at such other address as either party shall designate by formal written
notice.

      C. No presumption shall operate in favor of or against either party hereto
as a result of any responsibility either party may have had for drafting this
Agreement.

      IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
signed by their duly authorized officials as of the day and year first above
written.

                                    CNG TRANSMISSION CORPORATION
                                                    (Pipeline)


                                    By: /s/ George B. Carter
                                        -----------------------------
                                    Its: Vice President


                                    COLONIAL GAS COMPANY
                                                    (Customer)


                                    By: /s/ John P. Harrington
                                        -----------------------------

                                    Its: Senior V.P. - Gas Supply
                                        -----------------------------
                                                (Title)


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                         EXHIBIT A (Contract No. 300115)
               To The GSS (North Summit) Storage Service Agreement
                             Dated November 1, 1998
                    Between CNG Transmission Corporation and
                              Colonial Gas Company

A.    Quantities

      The quantities of natural gas storage service that Customer may utilize
under this Service Agreement, as well as Customer's applicable Billing
Determinants, are as follows:

      1.    For the period November 1, 1998 through and including October 31,
            1999:

            a.    A Storage Demand of 21 Dekatherms (Dt) per Day; and
            b.    A Storage Capacity of 2,080 Dt.

      2.    For the period November 1,1999 through and including October 31,
            2000:

            a.    A Storage Demand of 47 Dt per Day; and
            b.    A Storage Capacity of 4,680 Dt.

      3.    For the period November 1, 2000 through and including October 31,
            2001:

            a.    A Storage Demand of 67 Dt per Day; and
            b.    A Storage Capacity of 6,760 Dt.

      4.    For the period November 1, 2001 through and including October 31,
            2002:

            a.    A Storage Demand of 87 Dt per Day; and
            b.    A Storage Capacity of 8,840 Dt.

      5.    For the period November 1, 2002 through and including the remaining
            term of this Agreement:

            a.    A Storage Demand of 104 Dt per Day; and
            b.    A Storage Capacity of 10,400 Dt.

B.    Points of Receipt and Delivery

      1.    The Point of Receipt for Customer's tender of storage injection
            quantities, and the maximum quantities and character of service for
            such point shall be as set forth below. Each of the parties will use
            due care and diligence to assure that uniform pressures will be
            maintained at the Receipt Point as reasonably may be required to
            render service
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                                                 Exhibit A (Contract No. 300115)
                                   November 1, 1998 GSS (North Summit) Agreement
                                        Between CNG Transmission Corporation and
                                                            Colonial Gas Company
                                                                     Page 2 of 2

            hereunder, but Pipeline will not be required to accept gas at less
            than the minimum pressures specified herein.

            a.    Up to Customer's maximum daily entitlement for injection as
                  determined under Rate Schedule GSS, at an existing point of
                  interconnection between the facilities of Pipeline and Texas
                  Eastern Transmission Corporation (Texas Eastern) located in
                  Fayette County, Pennsylvania and known as the North Summit
                  Interconnection, at a pressure of not less than seven hundred
                  (700) pounds per square inch gauge ("psig").

      2.    The Points of Delivery for withdrawals from storage, and the maximum
            quantities and character of service for each point, shall be as set
            forth below. Each of the parties will use due care and diligence to
            assure that uniform pressures will be maintained at the Delivery
            Points as reasonably may be required to render service hereunder,
            but Pipeline will not be required to deliver gas at greater than the
            maximum pressures specified herein.

            a.    Up to Customer's maximum daily entitlement for withdrawal as
                  determined under Rate Schedule GSS, at an existing point of
                  interconnection between the facilities of Pipeline and Texas
                  Eastern located in Fayette County, Pennsylvania, known as the
                  North Summit Interconnection, at a pressure of not more than
                  one thousand (1,000) psig.

            b.    On an interruptible basis if operating conditions permit, up
                  to Customer's maximum daily entitlement for withdrawal as
                  determined under Rate Schedule GSS, at an existing point of
                  interconnection between the facilities of Pipeline and Texas
                  Eastern located in Greene County, Pennsylvania and known as
                  the Crayne Interconnection, at a pressure of not more than
                  eight hundred sixty-five (865) psig.

            c.    On an interruptible basis if operating conditions permit, up
                  to Customer's maximum daily entitlement for withdrawal as
                  determined under Rate Schedule GSS, at an existing point of
                  interconnection between the facilities of Pipeline and Texas
                  Eastern located in Westmoreland County, Pennsylvania and known
                  as the Oakford Interconnection, at a pressure of not less than
                  eight hundred fifty (850) psig.