Document:

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                                                                   Exhibit 10.50

                                                               Contract # 3.6724

                                SERVICE AGREEMENT

                                     between

                          PINE NEEDLE LNG COMPANY, LLC

                                       and

                       PIEDMONT NATURAL GAS COMPANY, INC.

                               September 13, 2000

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                                SERVICE AGREEMENT

         THIS AGREEMENT is entered into as of the 13th day of September, 2000,
by and between Pine Needle LNG Company, LLC, a North Carolina limited liability
company, hereinafter referred to as Pine Needle, and Piedmont Natural Gas
Company, Inc., hereinafter referred to as Customer,

                              W I T N E S S E T H:

         WHEREAS, Customer has requested firm storage service under Pine
Needle's Rate Schedule LNG-1; and

         WHEREAS, Pine Needle is willing to provide the requested firm storage
service for Customer pursuant to the terms and provisions of this Service
Agreement and Rate Schedule LNG-1.

         NOW, THEREFORE, Pine Needle and Customer agree as follows:

                                    ARTICLE I
                             SERVICE TO BE RENDERED

         Subject to the terms and provisions of this agreement and of Pine
Needle's Rate Schedule LNG-1, as amended from time to time, Pine Needle agrees
to receive and liquefy natural gas; store such gas in liquefied form; and
vaporize and deliver such gas to Customer or for Customer's account, as follows:

         To withdraw from storage, vaporize and deliver the gas stored in
liquefied form by Pine Needle for Customer's account up to a maximum quantity on
any day of 15,000 dt, which quantity shall be Customer's Vaporization Quantity.*

         To receive and liquefy natural gas for Customer up to a maximum
quantity on any day of 750 dt, which shall be Customer's Liquefaction
Quantity.*

         To store in liquefied form for Customer's account up to a total
quantity of 150,000 dt, which quantity shall be Customer's Storage Capacity.

------------------
* In addition to these quantities, Pine Needle shall retain quantities of gas
for fuel and gas otherwise used or lost and unaccounted for pursuant to Rate
Schedule LNG-1.

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                          SERVICE AGREEMENT (CONTINUED)

                                   ARTICLE II
                          POINT OF RECEIPT AND DELIVERY

         1. The Point of Receipt for all gas tendered to Pine Needle for
         liquefaction hereunder shall be at the following point:

                  The interconnection between Pine Needle's 10-inch inlet
                  pipeline and Transcontinental Gas Pipe Line Corporation's
                  (Transco) mainline system at mile post 1356.95 on Transco's
                  mainline in Guilford County, North Caroline.

         2. The Point of Delivery for all gas delivered by Pine Needle to
         Customer or for the account of Customer shall be at the following
         point:

                  The interconnection between Pine Needle's 24-inch outlet
                  pipeline and Transco's mainline system at milepost 1356.95 in
                  Guilford County, North Caroline.

                                   ARTICLE III
                                TERM OF AGREEMENT

         This agreement shall be effective as of October 1, 2000 and shall
remain in force and effect until March 31, 2005, and year to year thereafter,
subject to termination by either party upon two (2) years prior written notice
to the other.

                                   ARTICLE IV
                             RATE SCHEDULE AND PRICE

         1. Customer shall pay Pine Needle for service rendered hereunder in
accordance with Pine Needle's Rate Schedule LNG-1 and the applicable provisions
of the General Terms and Conditions of Pine Needle's Original Volume No. 1 FERC
Gas Tariff as filed with the Federal Energy Regulatory Commission, and as the
same may be amended or superseded from time to time. Such rate schedule and
General Terms and Conditions are by this reference made a part hereof.

         2. Pine Needle shall have the unilateral right to propose, file and
make effective with the Federal Energy Regulatory Commission, or other
regulatory authority having jurisdiction, changes and revisions to the rates and
rate design proposed pursuant to Section 4 of the Natural Gas Act, or to
propose, file and make effective superseding rates or rate schedules, for the
purposes of changing the rates, charges, rate design, terms and conditions of
service and other provisions thereof effective as to Customer; provided however
that the (i) firm character of service, (ii) term of agreement (as set forth in
Article III above), (iii) quantities, and (iv) points of receipt and delivery
shall not be subject to unilateral change under this paragraph. Customer shall
have the right to file with the Commission or other regulatory authority in
opposition to any such filings or proposals by Pine Needle.

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                          SERVICE AGREEMENT (CONTINUED)

                                    ARTICLE V
                                  MISCELLANEOUS

         1. The subject headings of the Articles of this agreement are inserted
for the purpose of convenient reference and are not intended to be a part of
this agreement nor to be considered in the interpretation of the same.

         2. This agreement supersedes and cancels as of the effective date
hereof the following contracts between the parties hereto: (None)

         3. 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.

         4. This agreement shall be interpreted, performed and enforced in
accordance with the laws of the State of North Carolina.

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

         6. 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 Pine Needle:
                   Pine Needle LNG Company, LLC
                   c/o  Pine Needle Operating Company
                   P.O. Box  1396
                   2800 Post Oak Boulevard  77056
                   Houston, Texas  77251-1396
                   Attention:  Director - Customer Service and Scheduling

             (b)   If to Customer:
                   Piedmont Natural Gas Company, Inc.
                   P. O. Box 33068
                   (1915 Rexford Road 28211)
                   Charlotte, North Carolina 28233
                   Attention:  Director - Federal Regulatory and Supply Planning

Such addresses may be changed from time to time by mailing appropriate notice
thereof to the other party.

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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
on the day and year above written.

                                            PINE NEEDLE LNG COMPANY, LLC
                                            by its agent
                                            PINE NEEDLE OPERATING COMPANY

                                            By   /s/ Frank  J. Ferazzi
                                                 -------------------------------
                                                  Frank J. Ferazzi
                                                  Vice President

                                            PIEDMONT NATURAL GAS COMPANY,INC.

                                            By   /s/ Thomas E. Skains
                                                 -------------------------------
                                                    Thomas E. Skains
                                                    Senior Vice President
                                                    Gas Supply and Services<PAGE>   1
                                                                   Exhibit 10.51

PINE NEEDLE LNG COMPANY, LLC
2800 Post Oak Boulevard (77056)
P. O. Box 1396
Houston, Texas  77251-1396
713/215-2000

September 13, 2000

Mr. Thomas Skains
Senior Vice President - Marketing and Supply Services
Piedmont Natural Gas Company, Inc.
1915 Rexford Road
Charlotte, NC   28233

Re:      Pine Needle LNG-1 Service Agreement

Dear Mr. Skains:

         Pine Needle LNG Company, LLC ("Pine Needle") and Piedmont Natural Gas
Company, Inc. ("Customer") are parties to that certain Service Agreement, dated
September 13th, 2000 ("Service Agreement"), wherein the Customer shall receive
up to 15,000 Dt per day of LNG vaporization service pursuant to Rate Schedule
LNG-1. The parties herein desire to amend the Service Agreement to change the
term provision.

     Accordingly, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:

     1. Effective as of October 1, 2000 Article III of the Service Agreement
shall be deleted in its entirety, and substituted therefor shall be the
following:

                               "TERM OF AGREEMENT

     This agreement shall be effective on October 1, 2000, and shall remain in
force and effect until March 31, 2005. Notwithstanding the fact that Customer
shall pay a discounted rate for service under the Service Agreement, Pine Needle
hereby grants to Customer a contractual Right of First Refusal ("ROFR"). This
ROFR will be procedurally administered in accordance with Section 23 of the
General Terms and Conditions of Pine Needle's FERC Gas Tariff, as amended from
time to time; provided that, in any event, Pine Needle shall provide notice of
termination to Customer 180 days prior to the expiration of the Service
Agreement to trigger the ROFR. Notwithstanding anything to the contrary in Pine
Needle's FERC Gas Tariff, in order to retain service beyond the termination date
pursuant its ROFR, Customer will required to match up to the maximum Pine Needle
rate and the maximum contractual term with a five (5) year matching cap, as is
allowed under a regulatory ROFR, of any bids submitted during an open season for
this service."

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Except as amended herein, all terms and conditions of the Service Agreement
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
executing both originals of this agreement in the space provided blow.

                                              Very truly yours,

                                                       PINE NEEDLE LNG COMPANY

                                              By: /s/ Frank J. Ferazzi
                                                  --------------------
                                                  Frank J. Ferazzi
                                                  Vice President
                                                  September 13, 2000

ACCEPTED AND AGREED:
PIEDMONT NATURAL GAS COMPANY

By:  /s/ Thomas E. Skains
     --------------------
     Thomas E. Skains
     Senior Vice President - Marketing and Supply Services
     September 13, 2000

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