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                                                                    EXHIBIT 10.6

                          PG&E-TRANS(SM) USER AGREEMENT

         This is a user agreement (hereafter the "Agreement") dated November 15,
1999, between PG&E GAS TRANSMISSION, NORTHWEST CORPORATION (hereafter "PG&E
GT-NW"), and Pacific Gas & Electric Co. (hereafter the "User"), for the use of
PG&E GT-NW's on-line services for conducting gas transportation and storage
related business, including PG&E-trans(SM), PG&E-trans(SM)nw, and
PG&E-trans(SM)northwest (hereafter collectively referred to as
"PG&E-trans(SM)").

         WHEREAS, access to PG&E-trans(SM) benefits User and is an integral
part of the provision of on-line services through the global communications
network by PG&E GT-NW, providing functions formerly accessible only upon PG&E
GT-NW's Pacific Trail(R) Electronic Bulletin Board Service; and

         WHEREAS, User desires to access and use PG&E-trans(SM), and bind itself
to reasonable terms and conditions of such access and use; and

         WHEREAS, User desires to submit nominations of gas to PG&E GT-NW under
applicable tariffs and such other available applications, current or future,
deemed necessary and made available by PG&E GT-NW through PG&E-trans(SM); and

         WHEREAS, User understands that by using PG&E-trans(SM), it may enter
into binding agreements with third parties;

         NOW, THEREFORE, the parties intending to be legally bound, agree as
follows:

1.       User understands and agrees that it may bind itself contractually to
         other users of PG&E-trans(SM) during the course of operating the
         natural gas posting or remarketing functions of the PG&E-trans(SM)
         system. User agrees that approving, agreeing to, or entering a
         transaction as provided by PG&E-trans(SM), as it now exists, or may in
         the future be modified, and subject to applicable tariffs, shall
         constitute a written contract (a "Contract"). By executing this
         Agreement, User agrees that it adopts any confirmation of a Contract as
         provided by PG&E-trans(SM) as User's signature, and such confirmation
         will, together with this Agreement, constitute an executed writing.
         User agrees to waive any Statute of Frauds defense to the
         enforceability of any Contract arising from use of PG&E-trans(SM). User
         agrees and warrants that any employee or agent of User using
         PG&E-trans(SM) shall have all necessary power and authority to use
         PG&E-trans(SM) and enter Contracts as herein provided. User warrants
         for itself, its successors and assigns that for each Contract that User
         may enter as a result of using PG&E-trans(SM), User shall have all
         right, title, power and authority necessary to honor said Contract.

PG&E-TRANS(SM) IS A SERVICE MARK OF PG&E CORPORATION.

PACIFIC TRAIL(R) IS A REGISTERED TRADEMARK OF PG&E GAS TRANSMISSION, NORTHWEST
CORPORATION.

PG&E Gas Transmission-Northwest and any other company referenced herein which
uses the PG&E name or logo are not the same company as Pacific Gas and Electric
Company, the California utility; neither PG&E Gas Transmission, Northwest
Corporation, nor these other referenced companies are regulated by the
California Public Utilities Commission, and customers do not have to buy
products from these companies in order to receive quality regulated services
from the utility.

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         1.1      User and PG&E GT-NW agree that this paragraph 1 is intended to
                  benefit users accessing PG&E-trans(SM), and that such other
                  users are third-party beneficiaries of said paragraph 1. User
                  and PG&E GT-NW do not intend hereby that other users are or
                  will be third-party beneficiaries of any other provisions of
                  this Agreement.

2.       User agrees that it shall be bound by all the terms and conditions of
         this Agreement, as well as any and all applicable tariffs currently in
         effect for PG&E GT-NW as approved by the Federal Energy Regulatory
         Commission ("FERC"), or which may hereafter be implemented. Such
         tariffs are matters of public record, which User warrants it has
         reviewed and will review in the future. User further agrees that PG&E
         GT-NW may modify or limit PG&E-trans(SM) at any time and without
         notice. From time to time, PG&E GT-NW may, at its sole discretion,
         develop updates or enhancements to the existing functionality of
         PG&E-trans(SM). If an update or enhancement is released to
         PG&E-trans(SM), such update or enhancement will be subject to the terms
         of this Agreement. PG&E GT-NW shall be under no obligation to provide
         any such updates or enhancements.

3.       PG&E GT-NW may terminate PG&E-trans(SM) and provide alternative
         electronic bulletin board access at any time in accordance with its
         tariffs, and may further terminate this Agreement with User, upon
         written notice by PG&E GT-NW, for cause, including failure to honor
         this Agreement, including applicable tariffs, failure to honor any
         Agreement entered through PG&E-trans(SM), PG&E GT-NW's Pacific Trail(R)
         Electronic Bulletin Board Service, or applicable PG&E GT-NW Electronic
         Data Interchange Trading Partner Agreement, failure to pay required
         reservation or demand charges, or failure to meet PG&E GT-NW's
         applicable credit requirements. Either party may terminate this
         Agreement upon thirty (30) days' notice, but no such termination
         (whether for cause or otherwise) shall affect User's obligation for
         Contracts entered during its use of PG&E-trans(SM). Without limiting
         other remedies, PG&E GT-NW may immediately issue a warning, temporarily
         suspend, indefinitely suspend or terminate this Agreement with User and
         refuse to provide access to PG&E-trans(SM) if PG&E GT-NW believes that
         User's actions may cause legal liability for User, third persons or
         PG&E GT-NW.

4.       User acknowledges that any submission under PG&E-trans(SM) may be
         subject to a credit review and approval requirement as may be
         applicable under PG&E GT-NW tariffs. User further acknowledges that it
         may not exceed its previously determined credit limit with respect to
         any bid. PG&E GT-NW may treat any bid that exceeds User's previously
         determined credit limit, at PG&E GT-NW's option, as a bid in an amount
         equal to the User's previously determined credit limit, or it may
         regard such a bid as void and of no effect.

5.       This Agreement shall become effective on the date first above written.
         Unless earlier terminated as provided in paragraph 3, this Agreement
         shall continue in effect for five (5) years thereafter, and shall
         automatically continue for succeeding five (5) year terms unless
         canceled by PG&E GT-NW at least thirty (30) days before the expiration
         of each such term.

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6.       If either party hereto shall fail to perform any obligation imposed
         upon it by this Agreement, and such failure shall be caused, or
         materially contributed to, by "force majeure," which means any act of
         God, strikes, lockouts, or other industrial disturbances, acts of
         public enemies, sabotage (whether or not performed by persons
         affiliated with parties hereto), wars, blockades, insurrections, riots,
         epidemics, landslides, lightning, electrical power failures,
         telecommunication system failures, earthquakes, floods, storms, fires,
         washouts, extreme cold or freezing weather, arrests and restraints of
         rulers or people, civil disturbances, explosions, breakage of or
         accident to machinery or lines of pipe, materials or equipment,
         computer hardware or software failure, legislative, administrative or
         judicial action which has been resisted in good faith by all reasonable
         legal means, any acts, omissions or causes whether of the kind herein
         enumerated or otherwise not reasonably within the control of the party
         invoking this paragraph and which by the exercise of due diligence such
         party could not have prevented the necessity for making repairs to,
         replacing, or reconditioning machinery, hardware, software, equipment,
         or pipelines, not resulting from the fault or negligence of the party
         invoking this paragraph, such failure shall be deemed not to be a
         breach of the obligation of such party, but such party shall use
         reasonable diligence to put itself in a position to carry out its
         obligations.

         6.1      Nothing contained herein shall be construed to require either
                  party to settle a strike or lockout by agreeing against its
                  judgment to the demands of the opposing parties. No such cause
                  as described in paragraph 6 affecting the performance of
                  either party shall continue to relieve such party from its
                  obligation after the expiration of a reasonable period of time
                  within which by the use of due diligence such party could have
                  remedied the situation preventing its performance, nor shall
                  any such cause relieve either party from any obligation unless
                  such party shall give notice thereof in writing to the other
                  party with reasonable promptness; and like notice shall be
                  given upon termination of such cause. Further, inasmuch as
                  this Agreement relates solely to PG&E-trans(SM), no such cause
                  as described in paragraph 6 shall, by the force of this
                  Agreement, have any effect on other agreements or tariffs
                  affecting the parties; specifically, no such cause as
                  described in paragraph 6 shall affect User's obligation to pay
                  any demand charges otherwise due to PG&E GT-NW.

7.       User agrees to defend, indemnify and hold harmless PG&E GT-NW, its
         officers, agents and employees against any liability, loss or damage
         whatsoever occurring in connection with or relating in any way to this
         Agreement or the use of PG&E-trans(SM), including costs and attorneys'
         fees, (where such liability, loss or damage results from any demand,
         claim, action, cause of action, or suit brought by User or by any
         person, association or entity, public or private, that is not a party
         to this Agreement) to the extent such liability, loss or damage is a
         direct or indirect result of any breach by User of this Agreement, or
         is a direct or indirect result of any sole or concurrent negligence or
         other tortious acts or omissions by User, its officers, agents or
         employees in the performance of this Agreement or through its use of
         PG&E-trans(SM).

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8.       User acknowledges that use of PG&E-trans(SM) by User involves
         transmission over the global communications network or Internet of
         proprietary and confidential information of User. PG&E GT-NW cannot
         guarantee the security of such information during its transmission by
         User over the global communications network or Internet. PG&E GT-NW
         will not be liable or responsible in any way to User for any losses,
         damages, claims, costs, expenses or other obligations arising out of or
         relating to any unauthorized access to or disclosure or use of such
         information transmitted over the global communications network or
         Internet. User further acknowledges and agrees that User is solely
         responsible for the accuracy of all information and data that User
         transmits to PG&E GT-NW, and PG&E GT-NW shall not be liable for any
         such inaccuracies.

9.       PG&E GT-NW does not represent or warrant that PG&E-trans(SM) will be
         uninterrupted or error-free, that defects will be corrected, or that
         PG&E-trans(SM) or the server that makes it available, are free of
         viruses or other harmful components. PG&E GT-NW does not warrant or
         represent that the use or the results of the use of PG&E-trans(SM) or
         the materials made available as part of PG&E-trans(SM) will be correct,
         accurate, timely, or otherwise reliable.

         User specifically agrees that PG&E GT-NW shall not be responsible for
         unauthorized access to or alteration of User's transmissions or data,
         any material or data sent or received or not sent or received, or any
         transactions entered into or through PG&E-trans(SM). User specifically
         agrees that PG&E GT-NW is not responsible or liable for any
         threatening, defamatory, obscene, offensive or illegal content or
         conduct of any other party or any infringement of another's rights,
         including intellectual property rights.

         PG&E GT-NW MAKES NO REPRESENTATIONS ABOUT THE SUITABILITY, RELIABILITY,
         AVAILABILITY, TIMELINESS, AND ACCURACY OF PG&E-TRANS(SM) FOR ANY
         PURPOSE. PG&E-TRANS(SM) IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
         KIND. PG&E GT-NW HEREBY DISCLAIMS ALL WARRANTIES AND CONDITIONS WITH
         REGARD TO PG&E-TRANS(SM), INCLUDING ALL IMPLIED WARRANTIES AND
         CONDITIONS OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE
         AND NON-INFRINGEMENT.

10.      Neither party shall be liable to the other for any special, incidental,
         exemplary or consequential damages arising from or as a result of any
         delay, omission or error in the electronic transmission or receipt of
         any information or data pursuant to this Agreement, or arising out of
         or in any way connected with the use or performance of PG&E-trans(SM)
         or related web sites, even if the other party has been advised of the
         possibility of such damages and regardless of negligence or fault.

11.      User agrees that the laws of the State of Oregon, without giving effect
         to choice of law provisions, shall govern the interpretation and
         enforcement of this Agreement. Any dispute or controversy arising from
         this Agreement or from PG&E GT-NW's operation of PG&E-trans(SM),
         whether arising in tort, contract or otherwise, shall be resolved as

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         provided in this paragraph 11. During the process of dispute
         resolution, the parties shall continue performance of their respective
         obligations under the Agreement.

         11.1     Prior to resorting to mediation or arbitration, the parties
                  agree to consult about any differences they may have under the
                  Agreement.

         11.2     If the parties are unable to agree after consultation, either
                  party may request, in writing, that mediation be undertaken to
                  attempt to reach agreement. The parties agree to attempt to
                  mediate their dispute through the selection of a mutually
                  acceptable neutral mediator upon such terms and conditions as
                  they might agree. Each party agrees to pay their own costs
                  associated with mediation and each agrees to pay one-half of
                  the fees of the mediator.

         11.3     If, after the period of thirty (30) days from the date of the
                  written notice requesting mediation, the parties are unable to
                  reach agreement through mediation, either party may call for
                  binding arbitration. Arbitration proceedings shall take place
                  in Portland, Oregon. The party calling for arbitration shall
                  serve notice in writing upon the other party, setting forth in
                  detail the question or questions to be arbitrated. The party
                  calling for arbitration shall, as part of its notice, propose
                  an arbitrator. The other party shall, within ten (10) days
                  after the receipt of such notice either agree to the proposed
                  arbitrator or reject the proposed arbitrator and may propose
                  an alternative arbitrator. If the alternative proposed
                  arbitrator is rejected, or the responding party refuses to
                  propose an arbitrator after ten (10) days, the party calling
                  for arbitration shall notify the Chief Judge of the United
                  States District Court for the District of Oregon and request
                  that he or she appoint an arbitrator qualified in matters
                  related to the interstate transportation of natural gas.

         11.4     The arbitrator shall apply applicable provisions of Oregon law
                  and the commercial arbitration rules of the American
                  Arbitration Association (to the extent consistent with the
                  procedures provided for herein) in reaching his or her
                  determination. The arbitrator shall make a determination
                  within sixty (60) days of the arbitrator's appointment.

         11.5     The determination by the arbitrator shall be binding on the
                  parties. The losing party shall pay all costs of the
                  arbitrator including fees and expenses. The prevailing party
                  shall be entitled to reasonable attorney's fees, costs and
                  expenses, including compensation for witnesses or consultants,
                  incurred in the arbitration.

         11.6     The award of the arbitrator shall be drawn up in writing and
                  signed by the arbitrator and shall be final and binding on
                  both PG&E GT-NW and User, and PG&E GT-NW and User shall abide
                  by the award and perform the terms and conditions thereof.
                  Unless otherwise determined by the arbitrator, the fees and
                  expenses of the arbitrator shall be paid in equal proportion
                  by PG&E GT-NW and User.

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12.      No waiver by either PG&E GT-NW or User of any default by the other in
         the performance of any provisions of this Agreement shall operate as a
         waiver of any continuing or future default, whether of a like or
         different character.

13.      PG&E GT-NW shall not be required to perform or continue PG&E-trans(SM)
         on behalf of any User that fails to comply with the terms contained in
         this Agreement, including applicable tariffs.

14.      PG&E GT-NW will provide User with a unique identification code,
         password and, in some cases depending upon the nature of User's access
         rights, a signature code, each of which shall be unique to each of
         User's authorized employees and without which User may not access
         PG&E-trans(SM). User shall complete an executed Appendix B for each of
         User's employees as designated by User for PG&E-trans(SM) access. User
         shall take all measures to maintain the secrecy and confidentiality of
         the password, identification code and, if applicable, signature code,
         to be provided to User. User acknowledges that a change in its
         password, identification code, or signature code may only be obtained
         from PG&E GT-NW by User's submission of a written request on Appendix
         B. User is entirely responsible for maintaining the confidentiality of
         its password, identification code and, if applicable, signature code
         (collectively "access codes") that uniquely identify the User and the
         employee authorized to act on behalf of the User. Furthermore, User is
         entirely responsible for any and all activities that occur under its
         account using the access codes. User acknowledges that it may, from
         time to time, terminate employees with knowledge of the access codes
         and agrees to take all steps to change one or more of the access codes
         to protect against unauthorized use of its account by submitting a
         revised Appendix B for that employee. User further agrees to notify
         PG&E GT-NW immediately of any unauthorized use of its account or any
         other breach of security. User acknowledges and consents that PG&E
         GT-NW, as the system operator and owner of PG&E-trans(SM), shall have
         access to, and the ability to review to the fullest extent allowed by
         law, all messages, electronic mail, files and other communications of
         any sort on PG&E-trans(SM), whether or not such communications are
         designated as private or confidential.

15.      User agrees to exercise due and reasonable care in the use of
         PG&E-trans(SM). User is solely responsible for obtaining all hardware,
         software, telecommunications lines and Internet or global
         communications network access that may be required to access
         PG&E-trans(SM).

16.      User acknowledges that PG&E GT-NW is the owner of all intellectual
         property rights to PG&E-trans(SM). PG&E-trans(SM) is intended for the
         posting, remarketing, and management of natural gas transportation and
         storage capacity on the natural gas pipeline owned by PG&E GT-NW. User
         understands that PG&E GT-NW is making access to PG&E-trans(SM)
         available to User for no direct charge, except for telephone or
         Internet access charges, which remain User's responsibility.

17.      In the event that User requests additional services or alternative
         access relating to PG&E-trans(SM), the parties may mutually agree on
         the pricing for such services in a separate

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         agreement. Any such additional services or alternative access relating
         to PG&E-trans(SM) are otherwise subject to the terms of this User
         Agreement.

18.      User agrees that PG&E GT-NW has extended access to PG&E-trans(SM) to
         User because of the specific business relationship between User and
         PG&E GT-NW, and in some cases because of User's particular credit
         history. This personal Agreement between User and PG&E GT-NW may not be
         assigned by User without the prior consent of PG&E GT-NW, which consent
         shall not unreasonably be withheld.

19.      All notices required or permitted to be given with respect to this
         Agreement shall be given by mailing the same postage prepaid, or given
         by facsimile or by courier, to the addressee party at such party's
         address as set forth in Appendix A. Either party may change its address
         for the purpose of notice hereunder by giving the other party no less
         than five (5) days' prior written notice of such new address in
         accordance with the preceding provisions.

20.      This Agreement may be executed in any number of original counterparts,
         all of which shall constitute one and the same instrument.

21.      Any provision of this Agreement that is determined to be invalid or
         unenforceable will be ineffective to the extent of such determination
         without invalidating the remaining provisions of this Agreement or
         affecting the validity or enforceability of such remaining provisions.

PG&E GAS TRANSMISSION,                           PACIFIC GAS & ELECTRIC CO.
NORTHWEST CORPORATION                            (PG&E CORE)

By: JAMES E. ROBBINS                              By: E. JAMES MACIAS
    ----------------------------                      --------------------------

Name: James E. Robbins                            Name: E. James Macias

Title: Director, Market Services                  Title: SVP & General Mgr, GT&S

                                                       (MUST BE SIGNED BY AN
                                                           OFFICER OF THE
                                                              COMPANY)

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                                   APPENDIX A

                               ADDRESS FOR NOTICE

If to PG&E GT-NW:

                  PG&E Gas Transmission, Northwest Corporation
                  2100 S.W. River Parkway
                  Portland, Oregon  97201
                  Telephone:        (503) 833-4301
                  Facsimile:        (503) 833-4900
                  Attention:        James E. Robbins

If to User:

Name:      Pacific Gas & Electric Co. (PG&E CORE)
Address:   77 Beale Street - M/C B5F
           San Francisco, CA  94105
Telephone: (415) 973-9035
Facsimile: (415) 973-9213
Attention: David W. Clare