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                                                                   EXHIBIT 10.40
                                                                Contract # .6425

                               SERVICE AGREEMENT

                                    between

                  TRANSCONTINENTAL GAS PIPE LINE CORPORATION

                                      and

                              BOSTON GAS COMPANY


                                 June 1, 1993
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                               SERVICE AGREEMENT

     THIS AGREEMENT entered into this first day of June, 1993, by and between
TRANSCONTINENTAL GAS PIPE LINE CORPORATION, a Delaware corporation, hereinafter
referred to as "Seller," first party, and BOSTON GAS COMPANY, hereinafter
referred to as "Buyer," second party,

                                  WITNESSETH

     WHEREAS, pursuant to the requirements of Order Nos. 636, 636-A and 636-B,
issued by the Federal Energy Regulatory Commission, Algonquin Gas Transmission
Company ("Algonquin") has assigned to several of its customers upstream capacity
previously provided under Seller's Rate Schedule X-284; and

     WHEREAS, upon the effective date of this Agreement, the contractual
arrangement between Algonquin and Seller is terminated and abandonment of
service under Rate Schedule X-284 is automatically authorized; and

     WHEREAS, Buyer has been assigned a portion of Algonquin's capacity
previously provided under Rate Schedule X-284, and agrees to such assignment and
assumes, in part, Algonquin's obligations pursuant to the Service Agreement and
Seller's FT Rate Schedule of Vol. 1 of its FERC Gas Tariff; and

     WHEREAS, Seller will provide Incremental Leidy Line Annual Firm
Transportation service hereunder to Buyer pursuant to Seller's blanket
certificate authorization and Rate Schedule FT for that portion of assigned
capacity designated hereinbelow.

     NOW, THEREFORE, Seller and Buyer agree as follows:


                                   ARTICLE I
                          GAS TRANSPORTATION SERVICE

     1.   Subject to the terms and provisions of this agreement and of Seller's
Rate Schedule FT, Buyer agrees to deliver or cause to be delivered to Seller gas
for transportation and Seller agrees to receive, transport and redeliver natural
gas to Buyer or for the account of Buyer, on a firm basis, up to the dekatherm
equivalent of a Transportation Contract Quantity ("TCQ") of 6,121 Mcf per day.
                                                             
     2.   Transportation service rendered hereunder shall not be subject to
curtailment or interruption except as provided in Section 1 of the General
Terms and Conditions of Seller's FERC Gas Tariff.

                                       2
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                               SERVICE AGREEMENT
                                  (Continued)

                                  ARTICLE II
                              POINT(S) OF RECEIPT

     Buyer shall deliver or cause to be delivered gas at the point(s) of receipt
hereunder at a pressure sufficient to allow the gas to enter Seller's pipeline
system at the varying pressures that may exist in such system from time to time;
provided, however, the pressure of the gas delivered or caused to be delivered
by Buyer shall not exceed the maximum operating pressure(s) of seller's pipeline
system at such point(s) of receipt. In the event the maximum operating
pressure(s) of Seller's pipeline system, at the point(s) of receipt hereunder,
is from time to time increased or decreased, then the maximum allowable
pressure(s) of the gas delivered or caused to be delivered by Buyer to Seller at
the point(s) of receipt shall be correspondingly increased or decreased upon
written notification of Seller to Buyer. The point(s) of receipt for natural gas
received for transportation pursuant to this agreement shall be:

     Point of Receipt
     ----------------

     Interconnection between the facilities
     of National Fuel and Seller at Wharton
     in Potter County, Pennsylvania.


                                  ARTICLE III
                             POINT(S) OF DELIVERY

     Seller shall redeliver to Buyer or for the account of Buyer the gas
transported hereunder at the following point(s) of delivery and at a pressure(s)
of:


     Point of Delivery                                   Pressure
     -----------------                                   --------

     Existing Centerville point of                       Prevailing pressure in
     interconnect between Algonquin Gas                  Seller's pipeline 
     Transmission Company and Seller                     system not to exceed 
     located in Somerset County, New Jersey              750 psig              
 
 
                                  ARTICLE IV
                                TERM OF AGREEMENT
 
      This agreement shall be effective as of June 1, 1993 and shall remain in
force and effect until 8:00 a.m. Eastern Standard Time

                                       3
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                               SERVICE AGREEMENT
                                  (Continued)

June 1, 2008 and thereafter until terminated by Seller or Buyer upon at least
one year prior written notice; provided, however, this agreement shall terminate
immediately and, subject to the receipt of necessary authorizations, if any,
Seller may discontinue service hereunder if (a) Buyer, in Seller's reasonable
judgement fails to demonstrate credit worthiness, and (b) Buyer fails to provide
adequate security in accordance with Section 8.3 of Seller's Rate Schedule FT.
As set forth in Section 8 of Article II of Seller's August 7, 1989 revised
Stipulation and Agreement in Docket Nos. RP88-68 et.al., (a) pregranted
abandonment under Section 284.221(d) of the Commission's Regulations shall not
apply to any long term conversions from firm sales service to transportation
service under Seller's Rate Schedule FT and (b) Seller shall not exercise its
right to terminate this service agreement as it applies to transportation
service resulting from conversions from firm sales service so long as Buyer is
willing to pay rates no less favorable than Seller is otherwise able to collect
from third parties for such service.


                                   ARTICLE V
                            RATE SCHEDULE AND PRICE

     1.   Buyer shall pay Seller for natural gas delivered to Buyer hereunder in
accordance with Seller's Rate Schedule FT and the applicable provisions of the
General Terms and Conditions of Seller's FERC Gas Tariff as filed with the
Federal Energy Regulatory Commission, and as the same may be legally amended or
superseded from time to time. Such Rate Schedule and General Terms and
Conditions are by this reference made a part hereof.

     2.   Seller and Buyer agree that the quantity of gas that Buyer delivers or
causes to be delivered to Seller shall include the quantity of gas retained by
Seller for applicable compressor fuel, line loss make-up (and injection fuel
under Seller's Rate Schedule GSS, if applicable) in providing the transportation
service hereunder, which quantity may be changed from time to time and which
will be specified in the currently effective Sheet No. 44 of Volume No. 1 of
this Tariff which relates to service under this agreement and which is
incorporated herein.

     3. In addition to the applicable charges for firm transportation service
pursuant to Section 3 of Seller's Rate Schedule FT, Buyer shall reimburse Seller
for any and all filing fees incurred as a result of buyer's request for service
under Seller's Rate Schedule FT, to the extent such fees are imposed upon Seller
by the Federal Energy Regulatory Commission or any successor governmental
authority having jurisdiction.

                                       4
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                               SERVICE AGREEMENT
                                  (Continued)


                                  ARTICLE VI
                                 MISCELLANEOUS

     1.  This Agreement supersedes and cancels as of the effective date hereof
the following contract(s):

          Algonquin/Transcontinental Gas Pipe Line Corporation former X-284
          Agreement, dated November 1, 1985; specifically for that portion of
          capacity provided in Article I above.

     2.   No waiver by either party of any one or more defaults by the other in
the performance of any provisions of this agreement shall operate or be
construed as a waiver of any future default or defaults, whether of a like or
different character.

     3.   The interpretation and performance of this agreement shall be in
accordance with the laws of the State of Texas, without recourse to the law
governing conflict of laws, and to all present and future valid laws with
respect to the subject matter, including present and future orders, rules and
regulations of duly constituted authorities.

     4.   This agreement shall be binding upon, and inure to the benefit of the
parties hereto and their respective successors and assigns.

     5.   Notices to either party shall be in writing and shall be considered as
duly delivered when mailed to the other party at the following address:

          (a)  If to Seller:
               Transcontinental Gas Pipe Line Corporation
               P. 0. Box 1396
               Houston, Texas     77251
               Attention:  Customer Services, Northern Market Area


          (b)  If to Buyer:
               Boston Gas Company               
               One Beacon Street                
               Boston, MA 02108                 
               Attention: Mr. William R. Luthern 
 
Such addresses may be changed from time to time by mailing appropriate notice
thereof to the other party by certified or registered mail.

                                       5
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                               SERVICE AGREEMENT
                                  (Continued)
                                        
     IN WITNESS WHEREOF, the parties hereto have caused this agreement to be
signed by their respective officers or representatives thereunto duly
authorized.


                              TRANSCONTINENTAL GAS PIPE LINE CORPORATION
                                                (Seller)
                                        

                              By   /s/ Thomas E. Skains
                                 ---------------------------------------  
                                       Thomas E. Skains 
                                       Senior Vice President
                                 Transportation and Customer Services


                                 BOSTON GAS COMPANY

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

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