EXHIBIT 4(f)


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                          NORTHWEST NATURAL GAS COMPANY


                                       TO


                      DEUTSCHE BANK TRUST COMPANY AMERICAS
                    (FORMERLY KNOWN AS BANKERS TRUST COMPANY)


                                       AND


            STANLEY BURG (SUCCESSOR TO R. G. PAGE AND J. C. KENNEDY),


                                        As Trustees under the Mortgage and
                                        Deed of Trust, dated as of July 1, 1946,
                                        of Portland Gas & Coke Company (now
                                        Northwest Natural Gas Company)


                        _________ SUPPLEMENTAL INDENTURE
                       PROVIDING, AMONG OTHER THINGS, FOR
                  FIRST MORTGAGE BONDS, _____% SERIES DUE _____


                              _____________________


                          DATED AS OF ________________


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                        __________ SUPPLEMENTAL INDENTURE


          INDENTURE, dated as of the ___ day of __________, made and entered
into by and between NORTHWEST NATURAL GAS COMPANY (formerly Portland Gas & Coke
Company), an Oregon corporation, with offices at One Pacific Square, 220 N.W.
Second Avenue, Portland, Oregon 97209 (hereinafter sometimes called the
Company), and DEUTSCHE BANK TRUST COMPANY AMERICAS (formerly known as BANKERS
TRUST COMPANY), a New York corporation, with offices at 60 Wall Street, New
York, New York 10005 (hereinafter sometimes called the Corporate Trustee) and
STANLEY BURG (successor to R. G. PAGE and J. C. KENNEDY), with offices at c/o
Deutsche Bank Trust Company Americas, 60 Wall Street, New York, New York 10005
(hereinafter sometimes called the Co-Trustee) (the Corporate Trustee and the
Co-Trustee together sometimes called the Trustees), as Trustees under the
Mortgage and Deed of Trust, dated as of July 1, 1946 (hereinafter called the
Mortgage), executed and delivered by Portland Gas & Coke Company (now Northwest
Natural Gas Company) to secure the payment of bonds issued or to be issued under
and in accordance with the provisions of the Mortgage, this indenture
(hereinafter called _________ Supplemental Indenture) being supplemental
thereto;

          WHEREAS the Mortgage was or is to be recorded in the official records
of various counties in the States of Oregon and Washington which counties
include or will include all counties in which this _____________ Supplemental
Indenture is to be recorded; and

          WHEREAS by the Mortgage the Company covenanted that it would execute
and deliver such supplemental indenture or indentures and such further
instruments and do such further acts as might be necessary or proper to carry
out more effectually the purposes of the Mortgage and to make subject to the
lien of the Mortgage any property thereafter acquired, made or constructed and
intended to be subject to the lien thereof; and

          WHEREAS the Company executed and delivered to the Trustees its First
Supplemental Indenture, dated as of June 1, 1949 (hereinafter called its First
Supplemental Indenture), its Second Supplemental Indenture, dated as of March 1,
1954 (hereinafter called its Second Supplemental Indenture), its Third
Supplemental Indenture, dated as of April 1, 1956 (hereinafter called its Third
Supplemental Indenture), its Fourth Supplemental Indenture, dated as of February
1, 1959 (hereinafter called its Fourth Supplemental Indenture), its Fifth
Supplemental Indenture, dated as of July 1, 1961 (hereinafter called its Fifth
Supplemental Indenture), its Sixth Supplemental Indenture, dated as of January
1, 1964 (hereinafter called its Sixth Supplemental Indenture), its Seventh
Supplemental Indenture, dated as of March 1, 1966 (hereinafter called its
Seventh Supplemental Indenture), its Eighth Supplemental Indenture, dated as of
December 1, 1969 (hereinafter called its Eighth Supplemental Indenture), its
Ninth Supplemental Indenture, dated as of April 1, 1971 (hereinafter called its
Ninth Supplemental Indenture), its Tenth Supplemental Indenture, dated as of
January 1, 1975 (hereinafter called its Tenth Supplemental Indenture), its
Eleventh Supplemental Indenture, dated as of December 1, 1975 (hereinafter
called its Eleventh Supplemental Indenture), its Twelfth Supplemental Indenture,
dated as of July 1, 1981 (hereinafter called its Twelfth Supplemental
Indenture), its Thirteenth Supplemental Indenture, dated as of June 1, 1985
(hereinafter called its Thirteenth Supplemental Indenture), its Fourteenth





Supplemental Indenture, dated as of November 1, 1985 (hereinafter called its
Fourteenth Supplemental Indenture), its Fifteenth Supplemental Indenture, dated
as of July 1, 1986 (hereinafter called its Fifteenth Supplemental Indenture),
its Sixteenth Supplemental Indenture, dated as of November 1, 1988 (hereinafter
called its Sixteenth Supplemental Indenture), its Seventeenth Supplemental
Indenture, dated as of October 1, 1989 (hereinafter called its Seventeenth
Supplemental Indenture), its Eighteenth Supplemental Indenture, dated as of July
1, 1990 (hereinafter called its Eighteenth Supplemental Indenture), its
Nineteenth Supplemental Indenture, dated as of June 1, 1991 (hereinafter called
its Nineteenth Supplemental Indenture); and

          WHEREAS the First through _____________ Supplemental Indentures were
filed for record, and were recorded and indexed, as a mortgage of both real and
personal property, in the official records of various counties in the States of
Oregon and Washington which counties include or will include all counties in
which this ____________ Supplemental Indenture is to be recorded; and

          WHEREAS the Company executed and delivered to the Trustees its
_____________ Supplemental Indenture, dated as of June 1, 1993 (hereinafter
called its Twentieth Supplemental Indenture); and

          WHEREAS said _______________ Supplemental Indenture was filed for
record, and was recorded and indexed, as a mortgage of both real and personal
property, and financing statements were filed, in the official records of the
several counties and other offices in the States of Oregon and Washington listed
below, as follows:


                                       2





                             IN THE STATE OF OREGON
                             ----------------------
                         Real Property Mortgage Records
                         ------------------------------

Counterpart
    No.             County         Date Recorded    Book, Film or Reel    Page
- -----------   ------------------   -------------    ------------------  --------
                                                              
              Benton
              Clackamas
              Clatsop
              Columbia
              Coos
              Douglas
              Hood River
              Lane
              Lincoln
              Linn
              Marion
              Multnomah
              Polk
              Tillamook
              Wasco
              Washington
              Yamhill




                         Filed as a Financing Statement
                         ------------------------------

Counterpart No.         Office         Date Filed for Record       File No.
- ---------------   ------------------   ---------------------   ----------------
                                                          
                  Secretary of State



                                       3





                           IN THE STATE OF WASHINGTON
                           --------------------------
                         Real Property Mortgage Records
                         ------------------------------

Counterpart
    No.             County         Date Recorded    Book, Film or Reel    Page
- -----------   ------------------   -------------    ------------------  --------
                                                              
              Clark
              Klickitat
              Skamania




                         Filed as a Financing Statement
                         ------------------------------

Counterpart No.         Office         Date Filed for Record       File No.
- ---------------   ------------------   ---------------------   ----------------
                                                          
                  Secretary of State



          WHEREAS an instrument dated as of June 14, 1951, was executed by the
Company appointing J. C. KENNEDY as Co-Trustee in succession to said R. G. PAGE
(resigned) under the Mortgage and by J. C. KENNEDY accepting the appointment as
Co-Trustee under the Mortgage in succession to R. G. PAGE, which instrument was
recorded in various counties in the States of Oregon and Washington; and

          WHEREAS, in the Ninth Supplemental Indenture STANLEY BURG was
appointed by the Company as Co-Trustee under the Mortgage in succession to J. C.
KENNEDY (resigned) and in the Ninth Supplemental Indenture STANLEY BURG accepted
such appointment as Co-Trustee under the Mortgage in succession to J. C.
KENNEDY; and

          WHEREAS in addition to the property described in the Mortgage, as
heretofore supplemented, the Company has acquired certain other property, rights
and interests in property; and

          WHEREAS, the Company has heretofore issued, in accordance with the
provisions of the Mortgage, as supplemented, and on the date hereof there remain
outstanding, the following serie(s) of First Mortgage Bonds:



                                                                Principal Amount
Series                                                            Outstanding
- ------                                                            -----------
                                                             
Secured Medium-Term Notes, Series A.......................      $_______________

Secured Medium-Term Notes, Series B.......................      $_______________


; and

          WHEREAS Section 8 of the Mortgage provides that the form of each
series of bonds (other than the First Series) issued thereunder shall be
established by Resolution of the Board of Directors of the Company; that the
form of such series, as established by the Board of Directors, shall specify the


                                       4



descriptive title of the bonds and various other terms thereof; and that such
Series may also contain such provisions not inconsistent with the provisions of
the Mortgage as the Board of Directors may, in its discretion, cause to be
inserted therein expressing or referring to the terms and conditions upon which
such bonds are to be issued and/or secured under the Mortgage; and

          WHEREAS Section 120 of the Mortgage provides, among other things, that
any power, privilege or right expressly or impliedly reserved to or in any way
conferred upon the Company by any provision of the Mortgage, whether such power,
privilege or right is in any way restricted or is unrestricted, may (to the
extent permitted by law) be in whole or in part waived or surrendered or
subjected to any restriction if at the time unrestricted or to additional
restriction if already restricted, and the Company may enter into any further
covenants, limitations or restrictions for the benefit of any one or more series
of bonds issued thereunder, or the Company may cure any ambiguity contained
therein or in any supplemental indenture or may (in lieu of establishment by
Resolution as provided in Section 8 of the Mortgage) establish the terms and
provisions of any series of bonds other than said First Series, by an instrument
in writing executed and acknowledged by the Company in such manner as would be
necessary to entitle a conveyance of real estate to record in all of the states
in which any property at the time subject to the lien of the Mortgage shall be
situated; and

          WHEREAS the Company now desires to create a new series of bonds and
(pursuant to the provisions of Section 120 of the Mortgage) to add to its
covenants and agreements contained in the Mortgage, as heretofore supplemented,
certain other covenants and agreements to be observed by it and to alter and
amend in certain respects the covenants and provisions contained in the
Mortgage, as heretofore supplemented and amended; and

          WHEREAS the execution and delivery by the Company of this _____
Supplemental Indenture, and the terms of the bonds of the _____ Series
hereinafter referred to, have been duly authorized by the Board of Directors of
the Company by appropriate resolutions of the Board of Directors;

          NOW, THEREFORE, THIS INDENTURE WITNESSETH:

          That Northwest Natural Gas Company, in consideration of the above
premises and such other valuable consideration, the receipt and sufficiency
whereof is hereby acknowledged, and in further assurance of the estate, title
and rights of the Trustees, and in order further to secure the payment both of
the principal of and interest and premium, if any, on the bonds from time to
time issued under the Mortgage, according to their tenor and effect, and the
performance of all the provisions of the Mortgage (including any instruments
supplemental thereto and any modification made as in the Mortgage provided) and
of said bonds, hereby grants, bargains, sells, releases, conveys, assigns,
transfers, mortgages, pledges, sets over and confirms (subject, however, to
Excepted Encumbrances, as defined in Section 6 of the Mortgage) unto Stanley
Burg and (to the extent of its legal capacity to hold the same for the purposes
hereof) to Deutsche Bank Trust Company Americas, as Trustees under the Mortgage,
and to their successor or successors in said trust, and to said Trustees and
their successors and assigns forever, all property, real, personal and mixed,
acquired by the Company after the date of the Mortgage, of the kind or nature
specifically mentioned in Article XXI of the Mortgage or of any other kind or


                                       5



nature (except any herein or in the Mortgage expressly excepted) now owned or,
subject to the provisions of subsection (I) of Section 87 of the Mortgage,
hereafter acquired by the Company (by purchase, consolidation, merger, donation,
construction, erection or in any other way) and wheresoever situated, including
(without in anywise limiting or impairing by the enumeration of the same the
scope and intent of the foregoing) all lands, gas plants, by-product plants, gas
holders, gas mains and pipes; all power sites, water rights, reservoirs, canals,
raceways, dams, aqueducts, and all other rights or means for appropriating,
conveying, storing and supplying water; all rights of way and roads; all plants
for the generation of electricity by steam, water and/or other power; all power
houses, street lighting systems, standards and other equipment incidental
thereto, telephone, radio, television and air-conditioning systems and equipment
incidental thereto, water works, water systems, steam heat and hot water plants,
substations, lines, service and supply systems, bridges, culverts, tracts, ice
or refrigeration plants and equipment, offices, buildings and other structures
and the equipment thereof; all machinery, engines, boilers, dynamos, gas,
electric and other machines, regulators, meters, transformers, generators,
motors, gas, electrical and mechanical appliances, conduits, cables, gas, water,
steam heat or other pipes, service pipes, fittings, valves and connections, pole
and transmission lines, wires, cables, tools, implements, apparatus, furniture
and chattels; all franchises, consents or permits; all lines for the
transmission and distribution of gas, electric current, steam heat or water for
any purpose including mains, pipes, conduits, towers, poles, wires, cables,
ducts and all apparatus for use in connection therewith; all real estate, lands,
easements, servitudes, licenses, permits, franchises, privileges, rights of way
and other rights in or relating to public or private property, real or personal,
or the occupancy of such property and (except as herein or in the Mortgage, as
heretofore supplemented, expressly excepted) all right, title and interest the
Company may now have or may hereafter acquire in and to any and all property of
any kind or nature wheresoever situated.

          TOGETHER WITH all and singular the tenements, hereditaments,
prescriptions, servitudes and appurtenances belonging or in anywise appertaining
to the aforementioned property or any part thereof, with the reversion and
reversions, remainder and remainders and (subject to the provisions of Section
57 of the Mortgage) the tolls, rents, revenues, issues, earnings, income,
product and profits thereof, and all the estate, right, title and interest and
claim whatsoever, at law as well as in equity, which the Company now has or may
hereafter acquire in and to the aforementioned property and franchises and every
part and parcel thereof.

          IT IS HEREBY AGREED by the Company that, subject to the provisions of
subsection (I) of Section 87 of the Mortgage, all the property, rights, and
franchises acquired by the Company (by purchase, consolidation, merger,
donation, construction, erection or in any other way) after the date hereof,
except any herein or in the Mortgage, as heretofore supplemented, expressly
excepted, shall be and are as fully granted and conveyed hereby and by the
Mortgage, and as fully embraced within the lien hereof and the lien of the
Mortgage, as supplemented, as if such property, rights and franchises were now
owned by the Company and were specifically described herein or in the Mortgage,
as heretofore supplemented, and conveyed hereby or thereby. Provided that the
following are not and are not intended to be now or hereafter granted,
bargained, sold, released, conveyed, assigned, transferred, mortgaged, pledged,
set over or confirmed hereunder and are hereby expressly excepted from the lien
and operation of this _________ Supplemental Indenture and from the lien and
operation of the Mortgage, as heretofore supplemented, viz: (1) cash, shares of
stock, bonds, notes and other obligations and other securities not hereafter


                                       6



specifically pledged, paid, deposited, delivered or held under the Mortgage, as
heretofore supplemented, or covenanted so to be; (2) merchandise, equipment,
apparatus, materials or supplies held for the purpose of sale or other
disposition in the usual course of business; fuel, oil and similar materials and
supplies consumable in the operation of any of the properties of the Company;
all aircraft, tractors, rolling stock, trolley coaches, buses, motor coaches,
automobiles, motor trucks, and other vehicles and materials and supplies held
for the purpose of repairing or replacing (in whole or in part) any of the same;
(3) bills, notes and accounts receivable, judgments, demands and choses in
action, and all contracts, leases and operating agreements not specifically
pledged under the Mortgage, as heretofore supplemented, or covenanted so to be;
(4) the last day of the term of any lease or leasehold which may be or become
subject to the lien of the Mortgage; (5) gas, petroleum, carbon, chemicals,
light oils, tar products, electric energy, steam, water, ice, and other
materials or products, manufactured, stored, generated, produced, purchased or
acquired by the Company for sale, distribution or use in the ordinary course of
its business; all timber, minerals, mineral rights and royalties and all Natural
Gas and Oil Production Property, as defined in Section 4 of the Mortgage; and
(6) the Company's franchise to be a corporation; provided, however, that the
property and rights expressly excepted from the lien and operation of this
_________ Supplemental Indenture and from the lien and operation of the
Mortgage, as heretofore supplemented, in the above subdivisions (2) and (3)
shall (to the extent permitted by law) cease to be so excepted in the event and
as of the date that either or both of the Trustees or a receiver or trustee
shall enter upon and take possession of the Mortgaged and Pledged Property in
the manner provided in Article XIII of the Mortgage by reason of the occurrence
of a Default as defined in Section 65 thereof.

          TO HAVE AND TO HOLD all such properties, real, personal and mixed,
granted, bargained, sold, released, conveyed, assigned, transferred, mortgaged,
pledged, set over or confirmed by the Company as aforesaid, or intended so to
be, unto Stanley Burg and (to the extent of its legal capacity to hold the same
for the purposes hereof) to Deutsche Bank Trust Company Americas, as Trustees,
and their successors and assigns forever.

          IN TRUST NEVERTHELESS, for the same purposes and upon the same terms,
trusts and conditions and subject to and with the same provisos and covenants as
are set forth in the Mortgage, as heretofore supplemented, this ________
Supplemental Indenture being supplemental thereto.

          AND IT IS HEREBY COVENANTED by the Company that all the terms,
conditions, provisos, covenants and provisions contained in the Mortgage, as
heretofore supplemented, shall affect and apply to the property hereinbefore
described and conveyed, and to the estates, rights, obligations and duties of
the Company and the Trustees and the beneficiaries of the trust with respect to
said property, and to the Trustees and their successors in the trust, in the
same manner and with the same effect as if the said property had been owned by
the Company at the time of the execution of the Mortgage, and had been
specifically and at length described in and conveyed to said Trustees by the
Mortgage as a part of the property therein stated to be conveyed.

          The Company further covenants and agrees to and with the Trustees and
their successors in said trust under the Mortgage, as follows:


                                       7



                                   ARTICLE I.

                         ______________ Series of Bonds.

     SECTION 1.01 There shall be a series of bonds designated "_______% Series
due _______" (herein sometimes referred to as the "_____________ Series"), each
of which shall also bear the descriptive title "First Mortgage Bond", and the
form thereof, which shall be established by Resolution of the Board of Directors
of the Company, shall contain suitable provisions with respect to the matters
hereinafter in this Article I specified. Bonds of the ______________ Series
shall be issued from time to time as fully registered bonds in denominations of
One Thousand Dollars and, at the option of the Company, in any multiple or
multiples of One Thousand Dollars (the exercise of such option to be evidenced
by the execution and delivery thereof). Bonds of the _____ Series shall bear
interest at the rate of ____ % per annum, payable semi-annually on _____ and
_____ of each year; and the principal of, and premium, if any, and interest on,
each such bond shall be payable at the office or agency of the Company in the
Borough of Manhattan, The City of New York, in such coin or currency of the
United States of America as at the time of payment is legal tender for public
and private debts. Bonds of the _______________ Series shall be dated as in
Section 10 of the Mortgage provided.

     (I) Bonds of the ___________ Series shall be redeemable on and after
______________ either at the option of the Company or pursuant to the
requirements of the Mortgage, in whole at any time, or in part from time to
time, prior to maturity, upon notice, as provided in Section 52 of the Mortgage,
mailed at least thirty (30) days prior to the date fixed for redemption, at the
following redemption prices, expressed in percentages of the principal amount of
the bonds to be redeemed:

                           [Insert redemption prices]

in each case, together with accrued interest to the date fixed for redemption.

     (II) At the option of the registered owner, any bonds of the _____________
Series, upon surrender thereof, for cancellation, at the office or agency of the
Company in the Borough of Manhattan, The City of New York, shall (subject to the
provisions of Section 12 of the Mortgage) be exchangeable for a like aggregate
principal amount of bonds of the same series of other authorized denominations.

     Transfers of bonds of the _____________ Series may be registered (subject
to the provisions of Section 12 of the Mortgage) at the office or agency of the
Company in the Borough of Manhattan, The City of New York.

     Upon any registration of transfer or exchange of bonds of the ____________
Series, the Company may make a charge therefor sufficient to reimburse it for
any tax or taxes or other governmental charge, as provided in Section 12 of the
Mortgage, but the Company hereby waives any right to make a charge in addition
thereto for any registration of exchange or transfer of bonds of the
____________ Series.


                                       8



                                  ARTICLE II.

                            Miscellaneous Provisions.

     SECTION 2.01 No bonds of the First through Third Series being Outstanding,
as permitted in Section 3 of the Third Supplemental Indenture, the amendment of
subdivision (A) of subsection (II) of Section 4 of the Mortgage made by Section
7 of the First Supplemental Indenture hereby is excised from the Mortgage, as
supplemented.

     SECTION 2.02 No bonds of the First through Ninth Series being Outstanding,
as permitted by Section 6 of the Ninth Supplemental Indenture, Article XIX of
the Mortgage, as supplemented, hereby is amended and restated in the manner and
form set forth in such Section 6.

     SECTION 2.03 No bonds of the First through Eleventh Series being
Outstanding, it is hereby confirmed that, as provided by Section 3.02 of the
Eleventh Supplemental Indenture, Section 64 of the Mortgage has been excised
from the Mortgage, as supplemented, effective as of the date of the retirement
of all of the bonds of such Series.

     SECTION 2.04 Subject to the amendments provided for in this ________
Supplemental Indenture, the terms defined in the Mortgage, as heretofore
supplemented, shall, for all purposes of this ________ Supplemental Indenture,
have the meanings specified in the Mortgage, as heretofore supplemented.

     SECTION 2.05 The holders of bonds of the ___________ Series consent that
the Company may, but shall not be obligated to, fix a record date for the
purpose of determining the holders of bonds of the ___________ Series entitled
to consent to any amendment, supplement or waiver. If a record date is fixed,
those persons who were holders at such record date (or their duly designated
proxies), and only those persons, shall be entitled to consent to such
amendment, supplement or waiver or to revoke any consent previously given,
whether or not such persons continue to be holders after such record date. No
such consent shall be valid or effective for more than 90 days after such record
date.

     SECTION 2.06 The Trustees hereby accept the trusts hereby declared,
provided, created or supplemented, and agree to perform the same upon the terms
and conditions herein and in the Mortgage, as heretofore supplemented, set
forth, including the following:

     The Trustees shall not be responsible in any manner whatsoever for or in
respect of the validity or sufficiency of this __________ Supplemental Indenture
or for or in respect of the recitals contained herein, all of which recitals are
made by the Company solely. In general each and every term and condition
contained in Article XVII of the Mortgage shall apply to and form part of this
________ Supplemental Indenture with the same force and effect as if the same
were herein set forth in full, with such omissions, variations and insertions,
if any, as may be appropriate to make the same conform to the provisions of this
____________ Supplemental Indenture.

     SECTION 2.07 Whenever in this ___________ Supplemental Indenture any of the
parties hereto is named or referred to, this shall, subject to the provisions of
Articles XVI and XVII of the Mortgage, be deemed to include the successors or


                                        9



assigns of such party, and all the covenants and agreements in this __________
Supplemental Indenture contained by or on behalf of the Company or by or on
behalf of the Trustees shall bind and inure to the benefit of the respective
successors and assigns of such parties whether so expressed or not.

     SECTION 2.08 Nothing in this _________ Supplemental Indenture, expressed or
implied, is intended, or shall be construed, to confer upon, or to give to, any
person, firm or corporation, other than the parties hereto and the holders of
the bonds and coupons outstanding under the Mortgage, any right, remedy, or
claim under or by reason of this __________ Supplemental Indenture or any
covenant, condition, stipulation, promise or agreement hereof, and all the
covenants, conditions, stipulations, promises and agreements by or on behalf of
the Company as set forth in this __________ Supplemental Indenture shall be for
the sole and exclusive benefit of the parties hereto, and of the holders of the
bonds and of the coupons outstanding under the Mortgage.

     SECTION 2.09 Except to the extent specifically provided herein, no
provision of this __________ Supplemental Indenture is intended to reinstate any
provisions in the Mortgage which were amended and superseded by the amendments
to the Trust Indenture Act of 1939 effective as of _______________.

     SECTION 2.10 This _________ Supplemental Indenture has been executed in
several identical counterparts, each of which shall be an original and all of
which shall constitute but one and the same instrument.

     IN WITNESS WHEREOF, Northwest Natural Gas Company, has caused its corporate
name to be hereunto affixed, and this instrument to be signed and sealed by its
President or one of its Vice Presidents, and its corporate seal to be attested
by its Secretary or one of its Assistant Secretaries for and in its behalf on
the _____ day of ________, as of ______, ____, in Portland, Oregon; Deutsche
Bank Trust Company Americas, has caused its corporate name to be hereunto
affixed, and this instrument to be signed and sealed by one of its Vice
Presidents or one of its Assistant Vice Presidents and its corporate seal to be
attested by one of its Assistant Secretaries on the ____ day of ___________, as
of _____________, in The City of New York; and Stanley Burg has hereunto set
his hand and affixed his seal, in The City of New York, on the _____ day of
________ as of ________________________.

                                         NORTHWEST NATURAL GAS COMPANY


                                         By___________________________


                                       10



Attest:


______________________________
Secretary

Executed, sealed and delivered by
NORTHWEST NATURAL GAS COMPANY
in the presence of:


______________________________


______________________________


                                         DEUTSCHE BANK TRUST COMPANY
                                         AMERICAS, as Trustee,


                                         By___________________________


Attest:


______________________________
Assistant Secretary


                                         _____________________________
                                         STANLEY BURG, as Trustee


Executed, sealed and delivered by
DEUTSCHE BANK TRUST COMPANY AMERICAS and
STANLEY BURG in the presence of:


______________________________


______________________________


                                       11



STATE OF OREGON        )
                       : ss.:
COUNTY OF MULTNOMAH    )

________________, A.D. _____.

          Before me personally appeared _______________, who, being duly sworn,
did say that he is ______________________________, of NORTHWEST NATURAL GAS
COMPANY and that the seal affixed to the foregoing instrument is the corporate
seal of said Corporation and that said instrument was signed and sealed in
behalf of said Corporation by authority of its Board of Directors; and he
acknowledged said instrument to be its voluntary act and deed.

          On this _____ day of ___________, before me personally appeared
____________________, to me known to be ___________________________ of NORTHWEST
NATURAL GAS COMPANY, one of the corporations that executed the within and
foregoing instrument, and acknowledged said instrument to be the free and
voluntary act and deed of said Corporation, for the uses and purposes therein
mentioned, and on oath stated that he was authorized to execute said instrument
and that the seal affixed is the corporate seal of said Corporation.

          IN WITNESS WHEREOF I have hereunto set my hand and affixed my official
seal the day and year first above written.


                                         __________________________________
                                         _____________________________
                                         Notary Public - Oregon
                                         Commission No. ________
                                         My Commission Expires ____________


                                       12



STATE OF NEW YORK      )
                       : ss.:
COUNTY OF NEW YORK     )

___________, A.D. ____.

          Before me personally appeared ______________, who, being duly sworn,
did say that he is an ______________________ of DEUTSCHE BANK TRUST COMPANY
AMERICAS and that the seal affixed to the foregoing instrument is the corporate
seal of said Corporation and that said instrument was signed and sealed in
behalf of said Corporation by authority of its Board of Directors; and he
acknowledged said instrument to be its voluntary act and deed.

          On this _____ day of _____________, before me personally appeared
____________________, to me known to be an ________________________ of DEUTSCHE
BANK TRUST COMPANY AMERICAS, one of the corporations that executed the within
and foregoing instrument, and acknowledged said instrument to be the free and
voluntary act and deed of said Corporation, for the uses and purposes therein
mentioned, and on oath stated that he was authorized to execute said instrument
and that the seal affixed is the corporate seal of said Corporation.

          IN WITNESS WHEREOF I have hereunto set my hand and affixed my official
seal the day and year first above written.


                                         ________________________________
                                         Notary Public, State of New York
                                         No. __________
                                         My Commission Expires ________


                                       13



STATE OF NEW YORK      )
                       : ss.:
COUNTY OF NEW YORK     )

___________, A.D. ____.

          Before me personally appeared the above-named STANLEY BURG and
acknowledged the foregoing instrument to be his voluntary act and deed.

          On this day personally appeared before me STANLEY BURG to me known to
be the individual described in and who executed the within and foregoing
instrument, and acknowledged that he signed the same as his free and voluntary
act and deed, for the uses and purposes therein mentioned.

          Given under my hand and official seal this ________ day of
___________________.


                                         ________________________________
                                         Notary Public, State of New York
                                         No. __________
                                         My Commission Expires ________


                                       14