Tennessee Gas Pipeline 1010 Milam Street [LOGO] A Tenneco Company P.O. Box 2511 Houston Texas 77252-2511 (713) 757-2131 EXHIBIT 10.16 July 21, 1995 Mr. Allen R. Neale Essex County Gas Co 7 North Hunt Road; P.O. Box 500 Amesbury, MA 01913 Re: Amendment No. 1 to Gas Storage Contract Dated December 1, 1994 Service Package No. 2272 Dear Allen: TENNESSEE GAS PIPELINE COMPANY (TENNESSEE) AND ESSEX COUNTY GAS CO (ESSEX) agree to amend the above referenced gas storage contract effective July 1, 1995, to increase the Maximum Daily Withdrawal Quantity (MDWQ) when Shipper's storage balance is equal to or less than 30% of the Maximum Storage Quantity (MSQ) and 20% of the MSQ, respectively, as reflected in the attached Exhibit A-1 and as described below. The parties agree to amend Article I of the subject gas storage contract as follows: Following the commencement of services hereunder, in accordance with the terms of Transporter's Rate Schedule FS, and of this Agreement, Transporter shall receive for injection for Shipper's account a daily quantity of gas up to Shipper's Maximum Injection Quantity of 5,476 dekatherms (Dth) and Maximum Storage Quantity (MSQ) of 821,460 (Dth) (on a cumulative basis) and on demand shall withdraw from Shipper's storage account and deliver to Shipper a daily quantity of gas up to Shipper's Maximum Daily Withdrawal Quantity (MDWQ) of 10,466 Dth; provided however, that when Shipper's storage balance is equal to or less than 30% of the MSQ but greater than 20% of the MSQ, the Maximum Daily Withdrawal Quantity shall be 9,540 Dth; and provided further, that when Shipper's storage balance is less than or equal to 20% of the MSQ, the Maximum Daily Withdrawal Quantity shall be 5,322 Dth. For demand charge purposes, the MDWQ for balances greater than 30% of the MSQ shall be used. Except as amended herein, all terms and provisions of the above referenced gas storage contract shall remain in full force and effect as written. If the foregoing is in accordance with your understanding of our agreement, please so indicate by signing and returning to my attention both originals of this letter. Upon Tennessee's execution, an original will be forwarded to you for your files. Tennessee Gas Pipeline ESSEX COUNTY GAS CO July 21, 1995 Page 2 Contract Number: 2272 Amendment number: 1 Amendment effective date: July 1, 1995 Should you have any questions, please do not hesitate to contact me at (713) 757-5125. Sincerely, /s/ John L. Templet John L. Templet Account Manager ACCEPTED AND AGREED TO This _____ day of ___________, 1995. TENNESSEE GAS PIPELINE COMPANY By: __________________________________ Title: Agent and Attorney-in-Fact Date: ________________________________ ACCEPTED AND AGREED TO This _____ day of ___________, 1995. ESSEX COUNTY GAS CO By: __________________________________ Title: _______________________________ Date: ________________________________ GAS STORAGE SERVICE AGREEMENT EXHIBIT "A-1" SHOWING REQUESTED CHANGES AMENDMENT #1 TO GAS STORAGE CONTRACT DATED December 1, 1994 BETWEEN TENNESSEE GAS PIPELINE COMPANY AND ESSEX COUNTY GAS COMPANY SERVICE PACKAGE MSQ: 821,460 Dth MAXIMUM DAILY INJECTION QUANTITY: 5,476 Dth MAXIMUM DAILY WITHDRAWAL QUANTITY (MDWQ): STORAGE BALANCE STORAGE BALANCE MAXIMUM DAILY WITHDRAWAL FROM DTH TO DTH QUANTITY DTH 246,439 821,460 10,466 Ratchet 0 164,293 246,438 9,540 Ratchet 1 0 164,292 5,322 Ratchet 2 SERVICE POINT: Compressor Station 313 INJECTION METER: 060018 TGP-NORTHERN STORAGE INJECTION WITHDRAWAL METER: 070018 TGP-NORTHERN STORAGE WITHDRAWAL STORAGE STORAGEMDIQ METER METER NAME COUNTY ST ZONE I/W LEG BALANCE FROM BALANCE TO MDWQ 060018 TGP-NORTHERN STORAGE INJECTION POTTER PA 04 I 300 5,476 070018 TGP-NORTHERN STORAGE WITHDRAWAL POTTER PA 04 W 300 246,439 821,460 10,466 Ratchet 0 164,293 246,438 9,540 Ratchet 1 0 164,292 5,322 Ratchet 2