<PAGE>

                                                                 Exhibit 10.27.1

                                                            Contract #: 800105R1

                               SERVICE AGREEMENT
                       (APPLICABLE TO RATE SCHEDULE FT-1)

      This Service Agreement, made and entered into this 29th day of October,
1999, by and between TEXAS EASTERN TRANSMISSION CORPORATION, a Delaware
Corporation (herein called "Pipeline") and BOSTON GAS COMPANY (herein called
"Customer", whether one or more),

                              W I T N E S S E T H:

      WHEREAS, Customer and Pipeline are parties to an executed service
agreement dated December 30, 1993, under Pipeline's Rate Schedule FT-1 (Pipeline
Contract No. 800105); and

      WHEREAS, Pipeline and Customer desire to enter into this Service Agreement
to supersede Pipeline's currently effective Contract No. 800105;

      NOW, THEREFORE, in consideration of the premises and of the mutual
covenants and agreements herein contained, the parties do covenant and agree as
follows:

                                   ARTICLE I

                               SCOPE OF AGREEMENT

      Subject to the terms, conditions and limitations hereof, of Pipeline's
Rate Schedule FT-1, and of the General Terms and Conditions, transportation
service hereunder will be firm. Subject to the terms, conditions and limitations
hereof and of Pipeline's Rate Schedule FT-1, Pipeline agrees to deliver for
Customer's account quantities of natural gas up to the following quantity:

                     Maximum Daily Quantity (MDQ) 39,624 dth

      provided, however, subject to Pipeline's receipt of one (1) year prior
      written notice Customer shall have a one time election to reduce to 22,586
      dth the MDQ of this Service Agreement with such reduction to be effective
      on November 1, 2005.
<PAGE>

                               SERVICE AGREEMENT
                             FOR RATE SCHEDULE FT-1
                                  (Continued)

      Pipeline shall receive for Customer's account, at those points on
Pipeline's system as specified in Article IV herein or available to Customer
pursuant to Section 14 of the General Terms and Conditions (hereinafter referred
to as Point(s) of Receipt) for transportation hereunder daily quantities of gas
up to Customer's MDQ, plus Applicable Shrinkage. Pipeline shall transport and
deliver for Customer's account, at those points on Pipeline's system as
specified in Article IV herein or available to Customer pursuant to Section 14
of the General Terms and Conditions (hereinafter referred to as Point(s) of
Delivery), such daily quantities tendered up to such Customer's MDQ.

      Pipeline shall not be obligated to, but may at its discretion, receive at
any Point of Receipt on any day a quantity of gas in excess of the applicable
Maximum Daily Receipt Obligation (MDRO), plus Applicable Shrinkage, but shall
not receive in the aggregate at all Points of Receipt on any day a quantity of
gas in excess of the applicable MDQ, plus Applicable Shrinkage. Pipeline shall
not be obligated to, but may at its discretion, deliver at any Point of Delivery
on any day a quantity of gas in excess of the applicable Maximum Daily Delivery
Obligation (MDDO), but shall not deliver in the aggregate at all Points of
Delivery on any day a quantity of gas in excess of the applicable MDQ.

      In addition to the MDQ and subject to the terms, conditions and
limitations hereof, Rate Schedule FT-1 and the General Terms and Conditions,
Pipeline shall deliver within the Access Area under this and all other service
agreements under Rate Schedules CDS, FT-1, and/or SCT, quantities up to
Customer's Operational Segment Capacity Entitlements, excluding those
Operational Segment Capacity Entitlements scheduled to meet Customer's MDQ, for
Customer's account, as requested on any day.

                                   ARTICLE II

                               TERM OF AGREEMENT

      The term of this Service Agreement shall commence on the later of November
1, 1999, or the in-service date of the facilities authorized by the Commission
in Docket No. CP99-113-000, and shall continue in force and effect until October
31, 2006, and year to year thereafter unless this Service Agreement is
terminated as hereinafter provided. This Service Agreement may be terminated by
either Pipeline or Customer upon one (1) year prior written notice to the other
specifying a termination date of October 31, 2006, or any October 31 thereafter.
Subject to Section 22 of Pipeline's General Terms and Conditions and without
prejudice to such rights, this Service Agreement may be terminated


                                       2
<PAGE>

                               SERVICE AGREEMENT
                             FOR RATE SCHEDULE FT-1
                                  (Continued)

at any time by Pipeline in the event Customer fails to pay part or all of the
amount of any bill for service hereunder and such failure continues for thirty
(30) days after payment is due; provided, Pipeline gives thirty (30) days prior
written notice to Customer of such termination and provided further such
termination shall not be effective if, prior to the date of termination,
Customer either pays such outstanding bill or furnishes a good and sufficient
surety bond guaranteeing payment to Pipeline of such outstanding bill.

      THE TERMINATION OF THIS SERVICE AGREEMENT WITH A FIXED CONTRACT TERM OR
THE PROVISION OF A TERMINATION NOTICE BY CUSTOMER TRIGGERS PREGRANTED
ABANDONMENT UNDER SECTION 7 OF THE NATURAL GAS ACT AS OF THE EFFECTIVE DATE OF
THE TERMINATION. PROVISION OF A TERMINATION NOTICE BY PIPELINE ALSO TRIGGERS
CUSTOMER'S RIGHT OF FIRST REFUSAL UNDER SECTION 3.13 OF THE GENERAL TERMS AND
CONDITIONS ON THE EFFECTIVE DATE OF THE TERMINATION.

      Any portions of this Service Agreement necessary to correct or cash-out
imbalances under this Service Agreement as required by the General Terms and
Conditions of Pipeline's FERC Gas Tariff, Volume No. 1, shall survive the other
parts of this Service Agreement until such time as such balancing has been
accomplished.

                                  ARTICLE III

                                 RATE SCHEDULE

      This Service Agreement in all respects shall be and remain subject to the
applicable provisions of Rate Schedule FT-1 and of the General Terms and
Conditions of Pipeline's FERC Gas Tariff on file with the Federal Energy
Regulatory Commission, all of which are by this reference made a part hereof.

      Customer shall pay Pipeline, for all services rendered hereunder and for
the availability of such service in the period stated, the applicable prices
established under Pipeline's Rate Schedule FT-1 as filed with the Federal Energy
Regulatory Commission, and as same may hereafter be legally amended or
superseded.

      Customer agrees that Pipeline shall have the unilateral right to file with
the appropriate regulatory authority and make changes effective in (a) the rates
and charges applicable to service pursuant to Pipeline's Rate Schedule FT-1, (b)
Pipeline's Rate Schedule FT-1 pursuant to which service hereunder is rendered or
(c) any provision of the General Terms and Conditions applicable to Rate
Schedule FT-1. Notwithstanding the foregoing, Customer does not agree that
Pipeline shall have the unilateral right without the consent of Customer
subsequent to the execution


                                       3
<PAGE>

                               SERVICE AGREEMENT
                             FOR RATE SCHEDULE FT-1
                                  (Continued)

of this Service Agreement and Pipeline shall not have the right during the
effectiveness of this Service Agreement to make any filings pursuant to Section
4 of the Natural Gas Act to change the MDQ specified in Article I, to change the
term of the agreement as specified in Article II, to change Point(s) of Receipt
specified in Article IV, to change the Point(s) of Delivery specified in Article
IV, or to change the firm character of the service hereunder. Pipeline agrees
that Customer may protest or contest the aforementioned filings, and Customer
does not waive any rights it may have with respect to such filings.

                                   ARTICLE IV

                  POINT(S) OF RECEIPT AND POINT(S) OF DELIVERY

      The Point(s) of Receipt and Point(s) of Delivery at which Pipeline shall
receive and deliver gas, respectively, shall be specified in Exhibit(s) A and B
of the executed service agreement. Customer's Zone Boundary Entry Quantity and
Zone Boundary Exit Quantity for each of Pipeline's zones shall be specified in
Exhibit C of the executed service agreement.

      Exhibit(s) A, B and C are hereby incorporated as part of this Service
Agreement for all intents and purposes as if fully copied and set forth herein
at length.

                                   ARTICLE V

                                    QUALITY

      All natural gas tendered to Pipeline for Customer's account shall conform
to the quality specifications set forth in Section 5 of Pipeline's General Terms
and Conditions. Customer agrees that in the event Customer tenders for service
hereunder and Pipeline agrees to accept natural gas which does not comply with
Pipeline's quality specifications, as expressly provided for in Section 5 of
Pipeline's General Terms and Conditions, Customer shall pay all costs associated
with processing of such gas as necessary to comply with such quality
specifications. Customer shall execute or cause its supplier to execute, if such
supplier has retained processing rights to the gas delivered to Customer, the
appropriate agreements prior to the commencement of service for the
transportation and processing of any liquefiable hydrocarbons and any PVR
quantities associated with the processing of gas received by Pipeline at the
Point(s) of Receipt under such Customer's service agreement. In addition,
subject to the execution of appropriate agreements, Pipeline is willing to
transport liquids associated with the gas produced and tendered for
transportation hereunder.


                                       4
<PAGE>

                               SERVICE AGREEMENT
                             FOR RATE SCHEDULE FT-1
                                  (Continued)

                                   ARTICLE VI

                                   ADDRESSES

      Except as herein otherwise provided or as provided in the General Terms
and Conditions of Pipeline's FERC Gas Tariff, any notice, request, demand,
statement, bill or payment provided for in this Service Agreement, or any notice
which any party may desire to give to the other, shall be in writing and shall
be considered as duly delivered when mailed by registered, certified, or regular
mail to the post office address of the parties hereto, as the case may be, as
follows:

      (a) Pipeline:     TEXAS EASTERN TRANSMISSION CORPORATION
                        5400 Westheimer Court
                        Houston, TX 77056-5310

      (b) Customer:     BOSTON GAS COMPANY
                        ONE BEACON STREET
                        BOSTON, MA 02108

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

                                  ARTICLE VII

                                  ASSIGNMENTS

      Any Company which shall succeed by purchase, merger, or consolidation to
the properties, substantially as an entirety, of Customer, or of Pipeline, as
the case may be, shall be entitled to the rights and shall be subject to the
obligations of its predecessor in title under this Service Agreement; and either
Customer or Pipeline may assign or pledge this Service Agreement under the
provisions of any mortgage, deed of trust, indenture, bank credit agreement,
assignment, receivable sale, or similar instrument which it has executed or may
execute hereafter; otherwise, neither Customer nor Pipeline shall assign this
Service Agreement or any of its rights hereunder unless it first shall have
obtained the consent thereto in writing of the other; provided further, however,
that neither Customer nor Pipeline shall be released from its obligations
hereunder without the consent of the other. In addition, Customer may assign its
rights to capacity pursuant to Section 3.14 of the General Terms and Conditions.
To the extent Customer so desires, when it releases capacity pursuant to Section
3.14 of the General Terms and Conditions, Customer may require privity between
Customer and the Replacement Customer, as further provided in the applicable
Capacity Release Umbrella Agreement.


                                       5
<PAGE>

                               SERVICE AGREEMENT
                             FOR RATE SCHEDULE FT-1
                                  (Continued)

                                  ARTICLE VIII

                                 INTERPRETATION

      The interpretation and performance of this Service Agreement shall be in
accordance with the laws of the State of Texas without recourse to the law
governing conflict of laws.

      This Service Agreement and the obligations of the parties are subject to
all present and future valid laws with respect to the subject matter, State and
Federal, and to all valid present and future orders, rules, and regulations of
duly constituted authorities having jurisdiction.

                                   ARTICLE IX

                       CANCELLATION OF PRIOR CONTRACT(S)

      This Service Agreement supersedes and cancels, as of the effective date of
this Service Agreement, the contract(s) between the parties hereto as described
below:

      service agreement dated December 30, 1993, between Pipeline and Customer
      under Pipeline's Rate Schedule FT-1 (Pipeline's Contract No. 800105).


                                       6
<PAGE>

                               SERVICE AGREEMENT
                             FOR RATE SCHEDULE FT-1
                                  (Continued)

      IN WITNESS WHEREOF, the parties hereto have caused this Service Agreement
to be signed by their respective Presidents, Vice Presidents or other duly
authorized agents and their respective corporate seals to be hereto affixed and
attested by their respective Secretaries or Assistant Secretaries, the day and
year first above written.

                                        TEXAS EASTERN TRANSMISSION CORPORATION


                                        By
                                           ------------------------------/s/ PMT

ATTEST:


---------------------------------------


                                        BOSTON GAS COMPANY


                                        By /s/ William R. Luthern
                                           -------------------------------------

ATTEST:

/s/ [ILLEGIBLE]
---------------------------------------


                                       7
<PAGE>

                                                              Contract #800105R1

                         EXHIBIT A, TRANSPORTATION PATHS
                      FOR BILLING PURPOSES, DATED 10/29/99,
                TO THE SERVICE AGREEMENT UNDER RATE SCHEDULE FT-1
           BETWEEN TEXAS EASTERN TRANSMISSION CORPORATION ("Pipeline")
              AND BOSTON GAS COMPANY ("Customer"), DATED 10/29/99:

(1)   Customer's firm Point(s) of Receipt:

<TABLE>
<CAPTION>
                                Maximum Daily
      Point                   Receipt Obligation
      of                        (plus Applicable     Measurement
      Receipt   Description       Shrinkage)       Responsibilities   Owner   Operator
      -------   -----------   ------------------   ----------------   -----   --------
      <S>       <C>           <C>                  <C>                <C>     <C>
      None
</TABLE>

(2)   Customer shall have Pipeline's Master Receipt Point List ("MRPL").
      Customer hereby agrees that Pipeline's MRPL as revised and published by
      Pipeline from time to time is incorporated herein by reference.

Customer hereby agrees to comply with the Receipt Pressure Obligation as set
forth in Section 6 of Pipeline's General Terms and Conditions at such Point(s)
of Receipt.

                                                      Transport at ion
                Transportation Path                 Path Quantity (Dth/D)
                -------------------                 ---------------------

                M1 to M3                                 39,624

SIGNED FOR IDENTIFICATION


PIPELINE:
          --------------------------/s/ JMM


CUSTOMER: /s/ W.R. Luthern
          --------------------------/s/ ED

SUPERSEDES EXHIBIT A DATED:
                            --------


                                      A-1
<PAGE>

                                                            Contract #: 800105R1

                EXHIBIT B, POINT(S) OF DELIVERY, DATED 10/29/99,
                TO THE SERVICE AGREEMENT UNDER RATE SCHEDULE FT-1
        BETWEEN TEXAS EASTERN TRANSMISSION CORPORATION ("Pipeline"), AND
                        BOSTON GAS COMPANY ("Customer"),
                                 DATED 10/29/99:

<TABLE>
<CAPTION>
                                       Maximum
                                       Daily                            Measurement
Point of                               Delivery     Delivery Pressure   Responsi-
Delivery        Description            Obligation   Obligation          Bilities      Owner     Operator
--------        -----------            ----------   -----------------   -----------   -----     --------
                                          (dth)
<S>        <C>                            <C>       <C>                 <C>           <C>       <C>
1.70087    ALGONQUIN - LAMBERTVILLE,      39,624    As requested by     TX EAST       TX EAST   ALGONQUIN
           NJ HUNTERDON CO., NJ                     customer, not to    TRAN          TRAN
                                                    exceed 750 PSIG
</TABLE>

SIGNED FOR IDENTIFICATION


PIPELINE:
          --------------------------/s/ JMM


CUSTOMER: /s/ W.R. Luthern
          --------------------------/s/ ED

SUPERSEDES EXHIBIT B DATED
                            --------


                                      B-1
<PAGE>

                                                            Contract #: 800105R1

    EXHIBIT C, ZONE BOUNDARY ENTRY QUANTITY AND ZONE BOUNDARY EXIT QUANTITY,
        DATED 10/29/99, TO THE SERVICE AGREEMENT UNDER RATE SCHEDULE FT-1
         BETWEEN TEXAS EASTERN TRANSMISSION CORPORATION ("PIPELINE") AND
                BOSTON GAS COMPANY ("CUSTOMER"), DATED 10/29/99:

                          ZONE BOUNDARY ENTRY QUANTITY

                                      Dth/D

                                       To

<TABLE>
<CAPTION>
============================================================================================================
FROM     STX   ETX   WLA  ELA   M1-24   M1-30   M1-TXG  M1-TGC   M2-24   M2-30   M2-TXG   M2-TGC   M2     M3
------------------------------------------------------------------------------------------------------------
<S>      <C>   <C>   <C>  <C>   <C>     <C>     <C>     <C>      <C>     <C>     <C>      <C>      <C> <C>
STX
------------------------------------------------------------------------------------------------------------
ETX                              5205             1700
------------------------------------------------------------------------------------------------------------
WLA                                                 48
------------------------------------------------------------------------------------------------------------
ELA                                     33315
------------------------------------------------------------------------------------------------------------
M1-24                                                            5205
------------------------------------------------------------------------------------------------------------
M1-30                                                                    33315
------------------------------------------------------------------------------------------------------------
M1-TXG                                                                           1748
------------------------------------------------------------------------------------------------------------
M1-TGC
------------------------------------------------------------------------------------------------------------
M2-24
------------------------------------------------------------------------------------------------------------
M2-30
------------------------------------------------------------------------------------------------------------
M2-TXG
------------------------------------------------------------------------------------------------------------
M2-TGC
------------------------------------------------------------------------------------------------------------
M2                                                                                                     39624
------------------------------------------------------------------------------------------------------------
M3
============================================================================================================
</TABLE>


                                       C-1
<PAGE>

                                                            Contract #: 800105R1

                              EXHIBIT C (Continued)
                               BOSTON GAS COMPANY
                           ZONE BOUNDARY EXIT QUANTITY
                                      Dth/D

                                       To

<TABLE>
<CAPTION>
============================================================================================================
FROM     STX   ETX   WLA  ELA   M1-24   M1-30   M1-TXG  M1-TGC   M2-24   M2-30   M2-TXG   M2-TGC   M2     M3
------------------------------------------------------------------------------------------------------------
<S>      <C>   <C>   <C>  <C>   <C>     <C>     <C>     <C>      <C>     <C>     <C>      <C>      <C> <C>
STX
------------------------------------------------------------------------------------------------------------
ETX
------------------------------------------------------------------------------------------------------------
WLA
------------------------------------------------------------------------------------------------------------
ELA
------------------------------------------------------------------------------------------------------------
M1-24                                                            5205
------------------------------------------------------------------------------------------------------------
M1-30                                                                    33315
------------------------------------------------------------------------------------------------------------
M1-TXG                                                                           1748
------------------------------------------------------------------------------------------------------------
M1-TGC
------------------------------------------------------------------------------------------------------------
M2-24
------------------------------------------------------------------------------------------------------------
M2-30
------------------------------------------------------------------------------------------------------------
M2-TXG
------------------------------------------------------------------------------------------------------------
M2-TGC
------------------------------------------------------------------------------------------------------------
M2                                                                                                     39624
------------------------------------------------------------------------------------------------------------
M3
============================================================================================================
</TABLE>

SIGNED FOR IDENTIFICATION


PIPELINE:
          --------------------------/s/ JMM


CUSTOMER: /s/ W.R. Luthern
          --------------------------/s/ ED


SUPERSEDES EXHIBIT C DATED
                            --------


                                       C-1