<PAGE>

                                                                     Exhibit 4.6

        ===============================================================


                          THE PROVIDENCE GAS COMPANY

                                      To

                     STATE STREET BANK AND TRUST COMPANY,

                                as Successor to

                     RHODE ISLAND HOSPITAL TRUST COMPANY,

                                    Trustee



                           _________________________

                       TWENTIETH SUPPLEMENTAL INDENTURE

                           ________________________

                         Dated as of February 1, 1999


     =====================================================================
<PAGE>

                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
SECTION                            HEADING                               PAGE
<S>                                                                      <C>
Parties..................................................................   1

FORM OF SERIES T BOND....................................................   2

ARTICLE FIRST.  DEFINITIONS..............................................   9

     Section 1.01.  General..............................................   9
     Section 1.02.  Trust Indenture Act..................................   9
     Section 1.03.  Definitions..........................................   9

ARTICLE SECOND. DESIGNATION AND TERMS OF SERIES T BONDS..................  11

     Section 2.01.  Establishment Of Series..............................  11
     Section 2.02.  Exchangeability Of Series T Bonds....................  12
     Section 2.03.  Special Record Date..................................  12

ARTICLE THIRD.  ISSUANCE OF $15,000,000 OF SERIES TO BONDS AND
                CLOSING OF SUCH SERIES AT THAT AMOUNT....................  12

     Section 3.01.  Issuance Of Series T Bonds...........................  12
     Section 3.02.  Limitation On Aggregate Principal Amount.............  12
     Section 3.03.  Cancellation Of Series T Bonds Paid, Etc.............  13
     Section 3.04.  Bonds Issuance In The Form Of a Global Note..........  13

ARTICLE FOURTH. REDEMPTION...............................................  14

     Section 4.01.  General..............................................  14
     Section 4.02.  Optional Redemption of Series T Bonds................  15
     Section 4.03.  Redemption Procedures................................  15
     Section 4.04.  Redemption at the Holder's Option....................  15

ARTICLE FIFTH.  SPECIAL INSURANCE PROVISIONS.............................  17

     Section 5.01.  Insurer as Third Party Beneficiary...................  17
     Section 5.02.  Notices and Information..............................  17
     Section 5.03.  Concerning the Special Insurance Provisions..........  17
     Section 5.04.  Amendments...........................................  18
     Section 5.05.  Limitation on Defeasance.............................  18
     Section 5.06.  Payments Under the Policy............................  18
     Section 5.07.  Insurer's Rights Concerning the Trustee..............  19
     Section 5.08.  Insurer's Right to Accelerate, etc...................  19
</TABLE>
<PAGE>

<TABLE>
<S>                                                                                                 <C>
ARTICLE SIXTH:  PARTICULAR PROVISIONS RELATED TO THE TRUST INDENTURE ACT..........................  20

     Section 6.01.  Deposited Moneys To Be Held In Trust By Trustee...............................  20
     Section 6.02.  Paying Agent to Repay Moneys Held.............................................  20
     Section 6.03.  Return of Unclaimed Moneys Held...............................................  20
     Section 6.04.  Provisions as to Paying Agent.................................................  20
     Section 6.05.  Certificates and Notice to Trustee............................................  21
     Section 6.06.  Company to Furnish Registered Owner Lists.....................................  21
     Section 6.07.  Preservation and Disclosure of Registered Owner Lists.........................  22
     Section 6.08.  Reports by the Company........................................................  23
     Section 6.09.  Reports by the Trustee........................................................  23
     Section 6.10.  Prohibition of Impairment of Registered Owner's Right to Payment..............  24
     Section 6.11.  Notice of Default.............................................................  24
     Section 6.12.  Undertaking to Pay Costs......................................................  24
     Section 6.13.  Conflict Interest of Trustee..................................................  25
     Section 6.14.  Existence and Eligibility of Trustee..........................................  25
     Section 6.15.  Resignation or Removal of Trustee.............................................  25
     Section 6.16.  Appointment of Successor Trustee..............................................  26
     Section 6.17.  Acceptance by Successor Trustee...............................................  26
     Section 6.18.  Limitations on Rights of Trustee as a Creditor................................  27
     Section 6.19.  Company-Owned Series T Bonds Disregarded......................................  27
     Section 6.20.  Business Days.................................................................  27
     Section 6.21.  Trust Indenture Act to Control................................................  27
     Section 6.22.  Manner of Mailing Notice to Registered Owner..................................  28

ARTICLE SEVENTH.  ADDITIONAL PROVISIONS...........................................................  28

     Section 7.01.  Title.........................................................................  28
     Section 7.02.  Released Property.............................................................  28
     Section 7.03.  Bonds Held by the Company.....................................................  28
     Section 7.04.  Payment of Series T Bonds.....................................................  28
     Section 7.05.  Events of Default.............................................................  29
     Section 7.06.  Expiration....................................................................  30
     Section 7.07.  Dates for Identification......................................................  30
     Section 7.08.  Section References............................................................  30
     Section 7.09.  Recordation...................................................................  30
     Section 7.10.  Replacement on Loss, Etc......................................................  30
     Section 7.11.  Counterparts..................................................................  31
     Section 7.12.  Rights and Remedies on Default................................................  31

Signatures........................................................................................  31
</TABLE>

ATTACHMENTS TO TWENTIETH SUPPLEMENTAL INDENTURE:

SCHEDULE I   - Schedule of Property and Interests Therein
SCHEDULE II  - Schedule of Released Property
SCHEDULE III - Form of Request for Redemption
<PAGE>

     THIS TWENTIETH SUPPLEMENTAL INDENTURE, dated as of February 1, 1999,
between THE PROVIDENCE GAS COMPANY, a corporation created by Special Act of the
General Assembly of the State of Rhode Island ( herein after sometimes called
the "Company"), party of the first part, and STATE STREET BANK AND TRUST
COMPANY, a Massachusetts trust company (successor to Rhode Island Hospital Trust
National Bank, which succeeded Rhode Island Hospital Trust Company), as trustee
under the Company's First Mortgage herein below mentioned (hereinafter sometimes
called the "Trustee"), party of the second part:

     WHEREAS the Company by an Indenture, dated as of January 1, 1922, as
supplemented by a First Supplemental Indenture, dated as of February 6, 1933, a
Second Supplemental Indenture, dated as of June 1, 1944, a Third Supplemental
Indenture, dated as of April 1, 1948, a Fourth Supplemental Indenture, dated as
of January 1, 1958, a Fifth Supplemental Indenture, dated as of July 1, 1960, a
Sixth Supplemental Indenture, dated as of September 1, 1963, a Seventh
Supplemental Indenture, dated as of November 1, 1971, an Eighth Supplemental
Indenture, dated as of July 1, 1972, a Ninth Supplemental Indenture, dated as of
October 1, 1975, a Tenth Supplemental Indenture, dated as of April 1, 1976, an
Eleventh Supplemental Indenture, dated as of September 1, 1978, a Twelfth
Supplemental Indenture, dated as of September 1, 1983, a Thirteenth Supplemental
Indenture, dated as of May 1, 1986, a Fourteenth Supplemental Indenture, dated
as of August 1, 1988, a Fifteenth Supplemental Indenture, dated as of June 1,
1990, a Sixteenth Supplemental Indenture, dated as of September 1, 1992, a
Seventeenth Supplemental Indenture, dated as of November 1, 1993, an Eighteenth
Supplemental Indenture, dated as of December 1, 1995, and a Nineteenth
Supplemental Indenture dated as of April 1, 1998 (said instruments being herein
after sometimes called, respectively, the "Original Indenture", the "First
Supplemental Indenture", the "Second Supplemental Indenture", the "Third
Supplemental Indenture", the "Fourth Supplemental Indenture", the "Fifth
Supplemental Indenture", the "Sixth Supplemental Indenture", the "Seventh
Supplemental Indenture", the "Eighth Supplemental Indenture", the "Ninth
Supplemental Indenture", the "Tenth Supplemental Indenture", the "Eleventh
Supplemental Indenture", the "Twelfth Supplemental Indenture", the "Thirteenth
Supplemental Indenture", the "Fourteenth Supplemental Indenture", the "Fifteenth
Supplemental Indenture", the "Sixteenth Supplemental Indenture", the
"Seventeenth Supplemental Indenture", the "Eighteenth Supplemental Indenture",
and the "Nineteenth Supplemental Indenture" and the Original Indenture as
supplemented by whatsoever supplements, including, if apt, this Twentieth
Supplemental Indenture, as have been or shall have been executed and delivered
at the pertinent time, being herein after sometimes called, collectively, the
"Indenture"), mortgaged its property and franchises, including after-acquired
property and franchises, to the Trustee to secure its First Mortgage Bonds
issued and to be issued thereunder in accordance with the provisions of said
Indenture, and there are now outstanding thereunder $2,728,000 principal amount
of First Mortgage Bonds, Series M, 10.25% due July

                                       1
<PAGE>

31, 2008, being all of an original issue of $10,000,000 principal amount of
bonds of said Series M, $10,000,000 principal amount of First Mortgage Bonds,
Series N, 9.63% due May 30, 2020, being all of an original issue of $10,000,000
principal amount of bonds of said Series N, $12,500,000 principal amount of
First Mortgage Bonds, Series O, 8.46% due September 30, 2022, being all of an
original issue of $12,500,000 principal amount of bonds of said Series O,
$12,500,000 principal amount of First Mortgage Bonds, Series P, 8.09% due
September 30, 2022, being all of an original issue of $12,500,000 principal
amount of bonds of said Series P, $8,000,000 principal amount of First Mortgage
Bonds, Series Q, 5.62% due November 30, 2003, being a portion of an original
issue of $16,000,000 principal amount of bonds of said Series Q, $15,000,000
principal amount of First Mortgage Bonds, Series R, 7.50% due December 15, 2025,
being all of an original issue of $15,000,000 principal amount of bonds of said
Series R; and $15,000,000 principal amount of First Mortgage Bonds, Series S,
6.82% due April 1, 2018; and

     WHEREAS the Company has determined, by due corporate action, to provide for
the immediate issuance, execution, authentication and delivery of $15,000,000 in
aggregate principal amount of its fully registered First Mortgage Bonds in the
principal amount of $15,000,000 to be known as the Company's First Mortgage
Bonds, Series T, 6.50% or, alternatively, as 6.50% Senior Secured Insured
Quarterly Notes (hereinafter sometimes called "bonds of Series T" or "Series T
bonds" or "Notes") due February 1, 2029; and

     WHEREAS each of the bonds to be issued hereunder and the certificate of the
Trustee to be endorsed on the bonds of such series are to be substantially in
the following forms, respectively, to wit:

[FORM OF SERIES T BOND - GLOBAL NOTE]


     THIS SECURITY IS A GLOBAL NOTE REGISTERED IN THE NAME OF THE DEPOSITARY
(REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED
IN WHOLE OR IN PART FOR THE INDIVIDUAL BONDS REPRESENTED HEREBY, THIS GLOBAL
NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF
THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER
NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A
SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.  UNLESS THIS
GLOBAL NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITARY TRUST
COMPANY (55 WATER STREET, NEW YORK, NEW YORK), TO THE TRUSTEE FOR REGISTRATION
OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN
THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND ANY PAYMENT IS MADE TO CEDE &
CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO
ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN
INTEREST HEREIN.

                                       2
<PAGE>

================================================================================


No. R-1                                              $15,000,000

                                                CUSIP 743753AC9

THE PROVIDENCE GAS COMPANY

FIRST MORTGAGE BOND, SERIES T, 6.50%

Due February 1, 2029

     THE PROVIDENCE GAS COMPANY, a corporation created by Special Act of the
General Assembly of the State of Rhode Island (herein after called the
"Company"), for value received, hereby promises to pay CEDE & CO., or registered
assigns, on the first day of February, 2029, the principal sum of Fifteen
Million Dollars ($15,000,000), and to pay interest thereon (unless this bond
shall have been called for previous redemption and payment duly provided
therefor) at the rate of six and one-half per cent (6.50%) per annum, from
February 8, 1999, payable quarterly in arrears on the first day of February,
May, August and November in each year (each such date, an "Interest Payment
Date"), commencing the first day of May, 1999, until said principal sum shall
have become due.  Interest shall be computed on the basis of a 360-day year of
twelve 30-day months.

     The interest so payable, and punctually paid or duly provided for, on any
Interest Payment Date will, as provided in the Indenture (as defined below), be
paid to the holder (the "Holder") of this bond (or one or more predecessor
bonds) of record at the close of business on the regular record date (the
"Regular Record Date") for such Interest Payment Date, which except in the case
of interest payable at the Stated Maturity (as defined in the Twentieth
Supplemental Indenture), shall be the fifteenth calendar day (whether or not a
Business Day) of the month preceding the month in which the respective Interest
Payment Date occurs, and, in the case of interest payable at the Stated
Maturity, shall be the date such that interest payable at the Stated Maturity is
payable to the same Person to whom principal on this bond is payable.

     Any such interest not so punctually paid or duly provided for shall
forthwith cease to be payable to the Holder on such Regular Record Date by
virtue of his having been such Holder, and may be paid to the Holder of this
bond (or one or more predecessor bonds) of record at the close of business on a
special record date (the "Special Record Date") fixed by the Trustee for the
payment of such defaulted interest, notice whereof shall be given to Holders not
less than 10 days prior to such Special Record Date, all as more fully provided
in the Twentieth Supplemental Indenture.

                                       3
<PAGE>

     The principal of and interest on this bond shall, subject to the provisions
of Section 7.04 of the Twentieth Supplemental Indenture hereinafter described,
be payable at the office of State Street Bank and Trust Company, in Boston,
Massachusetts (or at the office of its successor trustee in the trust to which
reference is herein after made), in such coin or currency of the United States
of America as shall be legal tender for the payment of public and private debts
at the time of payment.

     This bond is one of a duly authorized issue of First Mortgage Bonds of the
Company, unlimited as to aggregate principal amount except as set forth in the
Indenture hereinafter mentioned, issuable in series and is one of a series known
as First Mortgage Bonds, Series T, 6.50% (or alternatively, as 6.50% Senior
Secured Insured Quarterly Notes), all bonds of all series being issued and to be
issued under and pursuant to and all equally secured (except as any sinking or
other analogous fund, established in accordance with the provisions of the
Indenture hereinafter mentioned, may afford additional security for the bonds of
any particular series) by an Indenture, dated as of January 1, 1922, as
supplemented by a First Supplemental Indenture, dated as of February 6, 1933, a
Second Supplemental Indenture, dated as of June 1, 1944, a Third Supplemental
Indenture, dated as of April 1, 1948, a Fourth Supplemental Indenture, dated as
of January 1, 1958, a Fifth Supplemental Indenture, dated as of  July 1, 1960, a
Sixth Supplemental Indenture, dated as of September 1, 1963, a Seventh
Supplemental Indenture, dated as of November 1, 1971, an Eighth Supplemental
Indenture, dated as of  July 1, 1972, a Ninth Supplemental Indenture, dated as
of October 1, 1975, a Tenth Supplemental Indenture, dated as of April 1, 1976,
an Eleventh Supplemental Indenture, dated as of September 1, 1978, a Twelfth
Supplemental Indenture, dated as of September 1, 1983, a Thirteenth Supplemental
Indenture, dated as of May 1, 1986, a Fourteenth Supplemental Indenture, dated
as of August 1, 1988, a Fifteenth Supplemental Indenture, dated as of June 1,
1990, a Sixteenth Supplemental Indenture, dated as of September 1, 1992, a
Seventeenth Supplemental Indenture, dated as of November 1, 1993, an Eighteenth
Supplemental Indenture, dated as of December 1, 1995, a Nineteenth Supplemental
Indenture, dated as of April 1, 1998 and a Twentieth Supplemental Indenture
dated as of February 1, 1999 (said twenty-one instruments being hereinafter
called, collectively, the "Indenture"), all duly executed and delivered by the
Company to State Street Bank and Trust Company, in Boston Massachusetts, as
successor to Rhode Island Hospital Trust National Bank, which succeeded Rhode
Island Hospital Trust Company (hereinafter called the "Trustee"), as trustee, to
which Indenture and to all indentures supplemental thereto reference is hereby
made for a description of the property transferred, assigned and mortgaged
thereunder, the nature and extent of the security, the terms and conditions upon
which the bonds are secured and additional bonds may be issued and secured, and
the rights of the holders or registered owners of said bonds, of the Trustee and
of the Company in respect of such security.  Subsequent series of said

                                       4
<PAGE>

bonds may vary as to date, date of maturity, rate of interest and in other ways
as in the Indenture provided or permitted.

     Notwithstanding any provisions of the Indenture (including, without
limitation, Section 41 of the Original Indenture), the bonds of Series T shall
be subject to redemption only in the manner and to the extent provided in the
Twentieth Supplemental Indenture.

     As long as this bond is represented in global form (the "Global Note")
registered in the name of the Depository or its nominee, except as provided in
the Twentieth Supplemental Indenture and subject to certain limitations therein
set forth, no Global Note shall be exchangeable or transferable.

     If an Event of Default (as defined in the Indenture, including the
Twentieth Supplemental Indenture) with respect to the bonds shall occur and be
continuing, the principal plus any accrued interest may be declared due and
payable in the manner and with the effect and subject to the conditions provided
in the Indenture.

     In case of default by the Company, as set forth in the Indenture, the
principal of all the bonds of each and every series issued and outstanding
thereunder may be declared or may become due and payable in the manner and with
the effect provided in the Indenture.

     No recourse shall be had for the payment of any part of either the
principal of or interest on this bond, or for any claim based hereon, or
otherwise in any manner in respect hereof or in respect of the Indenture, to or
against any stockholder, officer or director, past, present or future, of the
Company, by virtue of any statute or provision or rule of law, or by the
enforcement of any assessment or penalty, all such liability being expressly
waived and released by the acceptance of this bond.

     This bond shall not become obligatory for any purpose until authenticated
by the execution by the Trustee of the certificate endorsed hereon.

                            STATEMENT OF INSURANCE

     The MBIA Insurance Corporation (the "Insurer") has issued a financial
guaranty insurance policy (the "Policy") containing the following provisions,
such Policy being on file at State Street Bank and Trust Company.

     The Insurer, in consideration of the payment of the premium and subject to
the terms of the Policy, hereby unconditionally and irrevocably guarantees to
any owner, as hereinafter defined, of the following described obligations, the
full and complete payment required to be made by or on behalf of the Company to
State Street Bank and Trust Company or its successor (the "Paying Agent") of an
amount equal to (i) the principal of (at the stated maturity) and

                                       5
<PAGE>

interest on, the Obligations (as that term is defined below) as such payments
shall become due but shall not be so paid (except that in the event of any
acceleration of the due date of such principal by reason of mandatory or
optional redemption or acceleration resulting from default or otherwise, the
payments guaranteed hereby shall be made in such amounts and at such times as
such payments of principal would have been due had there not been any such
acceleration); and (ii) the reimbursement of any such payment which is
subsequently recovered from any owner pursuant to a final judgment by a court of
competent jurisdiction that such payment constitutes an avoidable preference to
such owner within the meaning of any applicable bankruptcy law. The amounts
referred to in clauses (i) and (ii) of the preceding sentence shall be referred
to herein collectively as the "Insured Amounts." "Obligations" shall mean:

                                  $15,000,000
                          The Providence Gas Company
                    Senior Secured Insured Quarterly Notes
                      Due February 1, 2029 (IQ Notes/SM/)

     Upon receipt of telephonic or telegraphic notice, such notice subsequently
confirmed in writing by registered or certified mail, or upon receipt of written
notice by registered or certified mail, by the Insurer from the Paying Agent or
any owner of an Obligation the payment of an Insured Amount for which is then
due, that such required payment has not been made, the Insurer on the due date
of such payment or within one Business Day after receipt of notice of such
nonpayment, whichever is later, will make a deposit of funds, in an account with
State Street Bank and Trust Company, N.A., in New York, New York, or its
successor, sufficient for the payment of any such Insured Amounts which are then
due.  Upon presentment and surrender of such Obligations or presentment of such
other proof of ownership of the Obligations, together with any appropriate
instruments of assignment to evidence the assignment of the Insured Amounts due
on the Obligations as are paid by the Insurer, and appropriate instruments to
effect the appointment of the Insurer as agent for such owners of the
Obligations in any legal proceeding related to payment of Insured Amounts on the
Obligations, such instrument being in a form satisfactory to State Street Bank
and Trust Company, N.A., State Street Bank and Trust Company, N.A. shall
disburse to such owners or the Paying Agent payment of the Insured Amounts due
on such Obligations, less any amount held by the Paying Agent for the payment of
such Insured Amounts and legally available therefor.  The Policy does not insure
against loss of any prepayment premium which may at any time be payable with
respect to any Obligation.

     As used herein, the term "owner" shall mean the registered owner of any
Obligation as indicated in the books maintained by the Paying Agent, the
Company, or any designee of the Company for such purpose.  The term owner shall
not include the Company or any party whose agreement with the Company
constitutes the underlying security for the Obligations.

                                       6
<PAGE>

     Any service of process on the Insurer may be made to the Insurer at its
offices located at 113 King Street, Armonk, New York 10504 and such service of
process shall be valid and binding.

     The Policy is non-cancelable for any reason. The premium on the Policy is
not refundable for any reason including the payment prior to maturity of the
Obligations.

     The insurance provided by the Policy is not covered by the
Property/Casualty Insurance Security Fund specified in Article 76 of the New
York Insurance Law.

     Any provision of the Indenture may not be amended in any manner which
materially adversely affects the rights of the Insurer hereunder without the
prior written consent of the Insurer, which may not be unreasonably withheld,
conditioned or delayed.

     IN WITNESS WHEREOF, THE PROVIDENCE GAS COMPANY has caused its corporate
seal to be hereto affixed and this bond to be signed by its President or Vice
President and its Treasurer or Assistant Treasurer, the 8th day of February,
1999.


                                   THE PROVIDENCE GAS COMPANY


                                   By______________________________________
                                                  President

[CORPORATE SEAL]

                                   and
                                   By____________________________________
                                                  Treasurer

[FORM OF TRUSTEE'S CERTIFICATE]

     This is one of the bonds of Series T of the issue described in the
Indenture within mentioned.

                                   STATE STREET BANK AND TRUST COMPANY,
                                   as Successor to Rhode Island Hospital Trust
Company, Trustee


                                   By________________________________________
                                               Authorized Signature

     WHEREAS the Company also desires to confirm the lien of the Indenture upon
property (intended to be thereby mortgaged) acquired by

                                       7
<PAGE>

the Company since the execution of the Nineteenth Supplemental Indenture;

     NOW, THEREFORE, THIS TWENTIETH SUPPLEMENTAL INDENTURE WITNESSETH: That The
Providence Gas Company, pursuant to and in execution of the powers, authorities
and obligations conferred, imposed and reserved in the Original Indenture, as
heretofore supplemented by the First, Second, Third, Fourth, Fifth, Sixth,
Seventh, Eighth, Ninth, Tenth, Eleventh, Twelfth, Thirteenth, Fourteenth,
Fifteenth, Sixteenth, Seventeenth, Eighteenth and Nineteenth Supplemental
Indentures, and every other power, authority and obligation thereto appertaining
or enabling, in consideration of the premises and of the authentication,
purchase and acceptance of the Series T bonds, of $10 duly paid to the Company
by the Trustee and of other good and valuable consideration, receipt whereof is
hereby acknowledged, and for the purpose of confirming the Original Indenture
and said First, Second, Third, Fourth, Fifth, Sixth, Seventh, Eighth, Ninth,
Tenth, Eleventh, Twelfth, Thirteenth, Fourteenth, Fifteenth, Sixteenth,
Seventeenth, Eighteenth and Nineteenth Supplemental Indentures, as hereby
supplemented, and in order to secure, equally and ratably, the payment of the
principal of and the interest on all of the bonds at any time outstanding under
the Indenture according to their tenor, purport and effect and in order to
secure the faithful performance and observance of all of the covenants and
conditions set forth herein and in the Original Indenture, as heretofore
supplemented by the First, Second, Third, Fourth, Fifth, Sixth, Seventh, Eighth,
Ninth, Tenth, Eleventh, Twelfth, Thirteenth, Fourteenth, Fifteenth, Sixteenth,
Seventeenth, Eighteenth and Nineteenth Supplemental Indentures, by these
presents hereby confirms (except for property hereinafter expressly reserved and
excluded from the lien of the Indenture) the mortgage, conveyance, pledge,
assignment and transfer of the properties, franchises, rights and privileges set
forth and described in the Original Indenture and said Second, Third, Fourth,
Fifth, Sixth, Seventh, Eighth, Ninth, Tenth, Eleventh, Twelfth, Thirteenth,
Fourteenth, Fifteenth, Sixteenth, Seventeenth, Eighteenth and Nineteenth
Supplemental Indentures, and does hereby grant, bargain, sell, release, convey,
mortgage, confirm, assign, transfer, pledge and set over unto the Trustee, and
its successors in the trust, and its and their assigns, upon the trusts
established by the Indenture, all and singular:

     A.   The "Schedule of Property and Interests Therein" hereto attached as
Schedule I and made a part hereof.

     B.   The Company's gasworks, plant and machinery, purifiers, generators,
service and other pipes, holders, mains, meters, shops, tools, implements,
fixtures, appurtenances, and (except for property hereinafter expressly reserved
and excluded from the lien of the Indenture) all other real and tangible
personal property now owned or which shall hereafter be acquired by the Company,
or its successor or successors, and used or useful in connection with its
business of making, distributing, purchasing and selling gas, and with any other
business authorized or permitted by the Company's charter, and all of

                                       8
<PAGE>

the Company's leasehold interests in any of such property now or hereafter
leased by the Company as a lessee and all corporate and other franchises of the
Company, and all permits, ordinances, easements, privileges, immunities and
licenses, all rights to lay, construct, maintain and operate systems for the
distribution and transmission of gas and other agencies for the supply to itself
or others of light, heat and power, and all rights of way, grants and consents
which the Company now owns or which it may hereafter acquire, being intended to
include, among other things covered by the Indenture, the entire existing and
future light, heat and power business of the Company and all of its existing and
all of its future rights, franchises, permits, ordinances and licenses to
transact and conduct the same, and each and every part thereof (except as
hereinafter noted) as provided in the Original Indenture and said Second, Third,
Fourth, Fifth, Sixth, Seventh, Eighth, Ninth, Tenth, Eleventh, Twelfth,
Thirteenth, Fourteenth, Fifteenth, Sixteenth, Seventeenth, Eighteenth and
Nineteenth Supplemental Indentures, which are hereby made a part hereof, to the
same extent as if set forth herein at length, excepting, however, and there is
expressly reserved and excluded from the lien of the Indenture:

          (1)  Such of said properties or interests therein heretofore conveyed
     to the Trustee as may have been released by the Trustee or sold or
     otherwise disposed of as permitted by the provisions of the Indenture; and

          (2)  All right, title and interest of the Company now owned or
     hereafter acquired in and to

          (a)  all cash, bonds, shares of stock, obligations and other
          securities not deposited with the Trustee under the provisions of the
          Indenture;

          (b)  all accounts and bills receivable (other than for the recovery of
          real property or establishing a lien or charge thereon or right
          therein) and choses in action not specifically assigned to the Trustee
          and pledged with the Trustee hereunder;

          (c)  all goods, wares, merchandise, products and by-products held for
          sale in the ordinary course of business;

          (d)  all materials and supplies held for consumption in operation;

          (e)  all conversion burners, water heaters, stoves and refrigerators
          rented to customers or held for rental;

          (f)  all motor vehicles; and

          (3)  The last day of each of the demised terms created by any lease of
     property now leased to the Company and the last day

                                       9
<PAGE>

     of any demised term under each and every lease hereafter made or acquired
     by the Company and, under each and every renewal of any lease the last day
     of each and every such demised term being hereby expressly reserved to and
     by the Company;

until and unless a default shall be made in one or more obligations of the
Company under the Indenture and such default shall have continued beyond the
period of grace, if any, applicable in respect thereof, and the Trustee or any
receiver or other official shall take control of the mortgaged properties, in
which event the Indenture shall (to the extent permitted by law) become and be a
lien upon all of the classes of property set forth in 2 above (subject to any
liens or encumbrances then existing thereon), and the Trustee, receiver or other
official shall (to the extent permitted by law)  be entitled to possess, use and
dispose of the same in carrying on the operation of the Company's enterprise and
to include the same in any sale under power of sale conferred by the Indenture
or by law.

     TO HAVE AND TO HOLD all of said property, real, personal and mixed, now
owned or hereafter acquired, mortgaged and conveyed by the Company as aforesaid,
or intended so to be, unto the Trustee, and its successors in said trust, and to
them and to their assigns forever.

     IN TRUST, NEVERTHELESS, for the purposes, with the powers and subject to
the agreements, covenants and conditions set forth and expressed in the Original
Indenture, as supplemented and modified by the First Supplemental Indenture, the
Second Supplemental Indenture, the Third Supplemental Indenture, the Fourth
Supplemental Indenture, the Fifth Supplemental Indenture, the Sixth Supplemental
Indenture, the Seventh Supplemental Indenture, the Eighth Supplemental
Indenture, the Ninth Supplemental Indenture, the Tenth Supplemental Indenture,
the Eleventh Supplemental Indenture, the Twelfth Supplemental Indenture, the
Thirteenth Supplemental Indenture, the Fourteenth Supplemental Indenture, the
Fifteenth Supplemental Indenture, the Sixteenth Supplemental Indenture, the
Seventeenth Supplemental Indenture, Eighteenth Supplemental Indenture, the
Nineteenth Supplemental Indenture and this instrument, it being agreed as
follows, to wit:


                                 ARTICLE FIRST
                                  DEFINITIONS

     Section 1.01.  General.  The terms defined in this Article (whether or not
capitalized and except as herein otherwise expressly provided or unless the
context otherwise requires) for all purposes of this Twentieth Supplemental
Indenture shall have the respective meanings specified in this Article FIRST.

     Section 1.02.  Trust Indenture Act.  (a) Whenever this Indenture refers to
a provision of the Trust Indenture Act of 1939, as amended

                                       10
<PAGE>

(the "TIA"), such provision is incorporated by reference in and made a part of
this Indenture.

          (b)  Unless otherwise indicated, all terms used in this Twentieth
Supplemental Indenture that are defined by the TIA, defined by the TIA by
reference to another statute or defined by a rule of the Commission under the
TIA shall have the meanings assigned to them in the TIA or such statute or rule
as in force on the date of execution of this Twentieth Supplemental Indenture.

     Section 1.03.  Definitions.  For purposes of this Twentieth Supplemental
Indenture, the following terms shall have the following meanings:

     "Authorized Agent" shall mean any agent of the Company designated as such
by an Officers' Certificate delivered to the Trustee.

     "Board of Directors" shall mean the Board of Directors of the Company or
the Executive Committee of such Board or any other duly authorized committee of
such Board.

     "Board Resolution" shall mean a copy of a resolution certified by the
Secretary or an Assistant Secretary of the Company to have been duly adopted by
the Board of Directors and to be in full force and effect on the date of such
certification, and delivered to the Trustee.

     "Business Day" shall mean each Monday, Tuesday, Wednesday, Thursday and
Friday that is not a day on which banking institutions or trust companies in the
City of Boston, Commonwealth of Massachusetts, or in the city where the
corporate trust office of the Trustee is located, are obligated or authorized by
law or executive order to close or on which the office of the Insurer in the
Burrough of Manhattan, City of New York, State of New York, is closed.

     "Commission" shall mean the United States Securities and Exchange
Commission, or if at any time hereafter the Commission is not existing or
performing the duties now assigned to it under the TIA, then the body performing
such duties.

     "Company Order" shall mean a written order signed in the name of the
Company by one of the Chairman, the President, any Vice President (whether or
not designated by a number or numbers or a word or words added before or after
the title "Vice President"), the Treasurer or an Assistant Treasurer, of the
Company, and delivered to the Trustee.

     "Corporate Trust Office of the Trustee", or other similar term, shall mean
the corporate trust office of the Trustee, at which at any particular time its
corporate trust business shall be principally administered, which office is at
the date of the execution of this Indenture located at Two International Place,
4/th/ Floor, Boston,

                                       11
<PAGE>

Massachusetts 02110, Attention: Corporate Trust Administration (The Providence
Gas Company Twentieth Supplemental Indenture).

     "Depository" shall mean, unless otherwise specified in a Company Order, The
Depository Trust Company, New York, New York, or any successor thereto
registered and qualified as a clearing agency under the Securities Exchange Act
of 1934, or other applicable statute or regulation.

     "Event of Default" shall mean any event specified in Section 7.05 hereof,
continued for the period of time, if any, and after the giving of the notice, if
any, therein designated.

     "Global Note" shall mean a Series T bond that, pursuant to Section 3.04
hereof, is issued to evidence the Series T bonds, that is delivered to the
Depository or pursuant to the instructions of the Depository and that shall be
registered in the name of the Depository or its nominee.

     "Holder" shall mean (a) with respect to Series T bonds issued in the form
of a Global Note as provided in Section 3.04 hereof, any Person in whose name a
Series T bond is registered on the records of the Depository and (b) with
respect to Series T bonds issued in the form of individual Notes, the Registered
Owner thereof.

     "Insurance Paying Agent" shall have the meaning ascribed thereto in Section
5.06 hereof.

     "Insurer" shall mean MBIA Insurance Corporation, a New York domiciled stock
insurance company.

     "Interest Payment Date" shall mean (a) each date designated as such for the
payment of interest on the Series T bonds specified in this Twentieth
Supplemental Indenture, (b) a date of maturity of the Series T bonds and (c)
only with respect to defaulted interest on the Series T bonds, the date
established by the Trustee for the payment of such defaulted interest pursuant
to Section 2.03 hereof.

     "Note" or "Notes" shall mean the First Mortgage Bond(s), Series T, also
known as 6.50% Senior Secured Insured Quarterly Note(s).

     "Officers' Certificate" when used with respect to the Company, shall mean a
certificate signed by one of the Chairman, the President, any Vice President
(whether or not designated by a number or numbers or a word or words added
before or after the title "Vice President"), and by the Chief Financial Officer,
Treasurer, any Assistant Treasurer, the Secretary or an Assistant Secretary of
the Company; provided, that no individual shall be entitled to sign in more than
one capacity.

     "Original Issue Date" shall mean February 8, 1999.

                                       12
<PAGE>

     "Participant" shall mean one of the participating organizations for which
the Depository holds the Global Note.

     "Paying Agent" shall mean any Person (including the Company acting as
Paying Agent) authorized by the Company to pay the principal of or interest on
the Series T bonds on behalf of the Company.

     "Person" shall mean any individual, corporation, partnership, joint
venture, limited liability company, limited liability partnership or other
juridical entity, association, joint-stock company, trust, unincorporated
organization or government or any agent or political subdivision thereof.

     "Policy" shall mean the financial guaranty insurance policy issued by the
Insurer insuring the payment when due of the principal of and interest on the
Series T bonds as provided therein.

     "Redemption Date" shall mean with respect to any Series T bond to be
redeemed, in whole or in part, the date fixed for such redemption by or pursuant
to this Twentieth Supplemental Indenture.

     "Registered Owner" shall mean any Person in whose name a particular First
Mortgage Bond (including a Note) is registered on the books of the Trustee kept
for that purpose in accordance with the terms of the Indenture (including this
Twentieth Supplemental Indenture).

     "Regular Record Date" means the fifteenth (15/th/) calendar day (whether or
not a Business Day) of the month preceding the month in which the respective
Interest Payment Date occurs.

     "Principal Executive Offices of the Company" shall mean 100 Weybosset
Street, Providence, Rhode Island 02903, or such other place where the main
corporate offices of the Company are located as designated in writing to the
Trustee by an Authorized Agent.

     "Responsible Officer" or "Responsible Officers" when used with respect to
the Trustee shall mean any officer in the Corporate Trust Office of the Trustee
or any other officer to whom any corporate trust matter is referred because of
his or her knowledge of and familiarity with the particular subject.

     "Special Record Date" shall mean, with respect to any Series T bond, the
date established by the Trustee in connection with the payment of defaulted
interest on such Series T bond pursuant to Section 2.03 hereof.

     "Stated Maturity" means February 1, 2029.


                                ARTICLE SECOND
                    DESIGNATION AND TERMS OF SERIES T BONDS

                                       13
<PAGE>

     Section 2.01.   Establishment of Series.  There shall be and is hereby
created a new series of bonds entitled "First Mortgage Bonds, Series T, 6.50%"
also known as "6.50% Senior Secured Insured Quarterly Notes" (herein sometimes
called the "Series T bonds" or "bonds of Series T" or "Notes"), limited in
aggregate principal amount, except as noted in Section 3.02 hereof, to Fifteen
Million Dollars ($15,000,000), and to be issued as prescribed in Section 3.01
hereof.  Series T bonds shall be fully registered bonds in denominations of One
Thousand Dollars ($1,000) and multiples thereof.  All Series T bonds shall
mature February 1, 2029 and shall bear interest at the rate and payable at the
times specified in the form of Series T bond set forth herein.

     Interest shall be paid quarterly in arrears on each Interest Payment Date
to the Person in whose name the Series T bonds are registered on the Regular
Record Date for such Interest Payment Date.  Any such interest that is not so
punctually paid or duly provided for will forthwith cease to be payable to the
Registered Owners on such Regular Record Date and may either be paid to the
Person or Persons in whose name the Series T bonds are registered at the close
of business on a Special Record Date for the payment of such defaulted interest
to be fixed by the Trustee, notice whereof shall be given to Registered Owners
of the Series T bonds not less than ten (10) days prior to such Special Record
Date.

     Payments of interest on the Series T bonds will include interest accrued to
but excluding the respective Interest Payment Dates.  Interest payments for the
Series T bonds shall be computed and paid on the basis of a 360-day year of
twelve 30 day months.

     The principal of and interest on bonds of Series T shall, subject to the
provisions of Section 7.04 be payable at the office of the Trustee in such coin
or currency of  the United States of America as shall be legal tender for the
payment of public and private debts.

     Bonds of Series T shall be numbered "R-1" and consecutively upwards.

     Section 2.02.  Exchangeability of Series T Bonds.  Bonds of Series T shall
be exchangeable for a like aggregate principal amount of Series T bonds of
another authorized denomination or other authorized denominations.

     Section 2.03.  Special Record Date.  If and to the extent that the Company
fails to make timely payment or provision for timely payment of interest on any
Series T bond (other than on an Interest Payment Date that is a maturity date),
that interest shall cease to be payable to the Persons who were the Registered
Owners of such Series T bonds at the applicable Regular Record Date.  In that
event, when moneys become available for payment of the interest, the Trustee
shall (a) establish a date of payment of such interest and a Special Record

                                       14
<PAGE>

Date for the payment of that interest, which Special Record Date shall be not
more than fifteen (15) or fewer than ten (10) days prior to the date of the
proposed payment and (b) mail notice of the date of payment and of the Special
Record Date not fewer than ten (10) days preceding the Special Record Date to
each Registered Owner of such Series T bonds at the close of business on the
15/th/ day preceding the mailing at the address of such Registered Owner, as it
appeared on the register for the Series T bonds. On the day so established by
the Trustee the interest shall be payable to the Registered Owners of the Series
T bonds at the close of business on the Special Record Date.


                                 ARTICLE THIRD
                 ISSUANCE OF $15,000,000 OF SERIES T BONDS AND
                     CLOSING OF SUCH SERIES AT THAT AMOUNT

     Section 3.01.  Issuance of Series T Bonds.  Upon the execution and delivery
hereof, the Company will execute and deliver to the Trustee and the Trustee will
authenticate and deliver to the Company Fifteen Million Dollars ($15,000,000) in
aggregate principal amount of Series T bonds.

     Section 3.02.  Limitation on Aggregate Principal Amount.  The issue of
Series T bonds hereunder is hereby limited to the Fifteen Million Dollars
($15,000,000) in aggregate principal amount of bonds of such series to be
initially issued as provided in Section 3.01 hereof and to Series T bonds issued
in exchange or substitution for outstanding Series T bonds under the provisions
of the Indenture, permitting the exchange of bonds for other Series T bonds
(under the provisions of Section 2.02 hereof), or permitting the issuance of
bonds in lieu of lost, stolen, destroyed or mutilated bonds, or permitting the
exchange of definitive bonds for temporary bonds.

     Section 3.03.  Cancellation of Series T Bonds Paid, Etc.  All Series T
bonds surrendered for the purpose of payment, redemption, exchange or
registration of transfer shall be surrendered to the Trustee for cancellation
and promptly canceled by it and no Series T bonds shall be issued in lieu
thereof except as expressly permitted by this Twentieth Supplemental Indenture.
The Company shall surrender to the Trustee any Series T bonds so acquired by it
and such Series T bonds shall be canceled by the Trustee.  No Series T bonds
shall be authenticated in lieu of or in exchange for any Series T bonds so
canceled.

     Section 3.04.  Bonds Issuable in the Form of a Global Note.

     (a)  The Company shall execute and the Trustee shall, in accordance with
Section 3.01 hereof, authenticate and deliver the Series T bonds issuable
hereunder in the form of a Global Note or Global Notes, which (i) shall
represent, shall be denominated in an amount equal to the aggregate principal
amount of and shall have the same terms as the outstanding Series T bonds, (ii)
shall be registered

                                       15
<PAGE>

in the name of the Depository or its nominee, (iii) shall be delivered by the
Trustee to the Depository or pursuant to the Depository's instruction and (iv)
shall bear a legend substantially to the following effect: "This Security is a
Global Note registered in the name of the Depository (referred to herein) or a
nominee thereof and, unless and until it is exchanged in whole or in part for
the individual Notes represented hereby, this Global Note may not be transferred
except as a whole by the Depository to a nominee of the Depository or by a
nominee of the Depository to the Depository or another nominee of the Depository
or by the Depository or any such nominee to a successor Depository or a nominee
of such successor Depository or a nominee of such successor Depository. Unless
this Global Note is presented by an authorized representative of The Depository
Trust Company (55 Water Street, New York, New York) to the Trustee for
registration of transfer, exchange or payment and any certificate issued is
registered in the name of Cede & Co. or such other name as requested by an
authorized representative of The Depository Trust Company and any payment is
made to Cede & Co., any transfer, pledge or other use hereof for value or
otherwise by or to any person is wrongful since the registered owner hereof,
Cede & Co., has an interest herein" or such other legend as may be required by
the rules and regulations of the Depository.

     (b)  Notwithstanding any other provision of the Indenture, a Global Note
may be transferred, in whole but not in part, only as described in the legend
thereto.

          (c)  (i) If at any time the Depository for a Global Note notifies the
     Company that it is unwilling or unable to continue as Depository for such
     Global Note or if at any time the Depository for the Global Note shall no
     longer be eligible or in good standing under the Securities Exchange Act of
     1934 or other applicable statute or regulation, the Company shall appoint a
     successor Depository with respect to such Global Note. If a successor
     Depository for such Global Note is not appointed by the Company within
     ninety (90) days after the Company receives such notice or becomes aware of
     such ineligibility, the Company shall execute, and the Trustee, upon
     receipt of a Company Order for the authentication and delivery of
     individual Notes of such series in exchange for such Global Note, shall
     authenticate and deliver, individual Notes of such series of like tenor and
     terms in definitive form in an aggregate principal amount equal to the
     principal amount of the Global Note in exchange for such Global Note. The
     Trustee shall not be charged with knowledge or notice of the ineligibility
     of a Depository unless a Responsible Officer of the Trustee shall have
     actual knowledge thereof.

          (ii) (A) The Company may at any time and in its sole discretion
     determine that all outstanding (but not less than all) Notes evidencing the
     Series T bonds issued or issuable in the form of one or more Global Notes
     shall no longer be represented by such Global Note or Notes. In such event
     the Company shall

                                       16
<PAGE>

     execute, and the Trustee, upon receipt of a Company Order for the
     authentication and delivery of individual Notes in exchange for such Global
     Note, shall authenticate and deliver individual Notes of like tenor and
     terms in definitive form in an aggregate principal amount equal to the
     principal amount of such Global Note or Notes in exchange for such Global
     Note or Notes.

                (B)  Within seven (7) days after the occurrence of an Event of
     Default with respect to any Global Notes, the Company shall execute, and
     the Trustee shall authenticate and deliver, Notes evidencing such Series T
     bonds in definitive registered form in any authorized denominations and in
     aggregate principal amount equal to the principal amount of the Global
     Notes in exchange for such Global Notes.

          (iii) In any exchange provided for in either of the preceding two
     paragraphs, the Company will execute and the Trustee will authenticate and
     deliver individual Notes in definitive registered form in authorized
     denominations. Upon the exchange of a Global Note for individual Notes,
     such Global Note shall be canceled by the Trustee. Notes issued in exchange
     for a Global Note pursuant to this Section shall be registered in such
     names and in such authorized denominations as the Depository for such
     Global Note, pursuant to instructions from its direct or indirect
     Participants or otherwise, shall instruct the Trustee. The Trustee shall
     deliver such Notes to the Depository for delivery to the Persons in whose
     names such Notes are so registered, or if the Depository shall refuse or be
     unable to deliver such Notes, the Trustee shall deliver such Notes to the
     Persons in whose names such Notes are registered, unless otherwise agreed
     upon between the Trustee and the Company, in which event the Company shall
     cause the Notes to be delivered to the Persons in whose names such Notes
     are registered.

     (d)  None of the Company, the Trustee, any authenticating agent or any
Paying Agent shall have any responsibility or liability for any aspect of the
records relating to, or payments made on account of, beneficial ownership
interests of a Global Note or for maintaining, supervising or reviewing any
records relating to such beneficial ownership interests.

     (e)  If the principal amount of part, but not all of a Global Note is paid,
then upon surrender to the Trustee of such Global Note, the Company shall
execute, and the Trustee shall authenticate, deliver and register, a Global Note
in an authorized denomination in aggregate principal amount equal to, and having
the same terms, Original Issue Date and series as, the unpaid portion of such
Global Note.


                                ARTICLE FOURTH
                                  REDEMPTION

                                       17
<PAGE>

     Section 4.01.  General.  Notwithstanding any provisions of the Indenture
(including, without limitation, Section 41 thereof) the bonds of Series T shall
be subject to redemption only in the manner and to the extent provided in this
Article FOURTH.

     Section 4.02.  Optional Redemption of Series T Bonds.  The Company shall
have the option, at any time and from time to time on or after February 1, 2004,
of redeeming the outstanding Series T bonds, either in whole or in part, upon
not less than thirty (30) days' nor more than sixty (60) days' prior written
notice to each Registered Owner, by payment of the principal amount of the
Series T bonds to be redeemed (the "Redemption Price"), and accrued interest
thereon to, but not including, the Redemption Date.

     If notice of redemption is given as aforesaid, the Series T bonds so to be
redeemed shall, on the Redemption Date, become due and payable at the Redemption
Price together with any accrued interest thereon, and from and after such date
(unless the Company shall default in the payment of the Redemption Price and
accrued interest) the Series T bonds shall cease to bear interest.  If any
Series T bond called for redemption shall not be paid upon surrender thereof for
redemption, the principal shall, until paid, bear interest from the Redemption
Date at 6.50%. Subject to the foregoing and applicable law (including without
limitation, United States federal securities laws), the Company or its
affiliates may, at any time and from time to time, purchase outstanding Series T
bonds by tender, in the open market or by private agreement.

     Section 4.03.  Redemption Procedures.  Except as herein otherwise set
forth, the provisions of Article Fourth of the Original Indenture, with respect
to the procedures for call and redemption, prior to maturity, of Series A and
Series B bonds, shall apply to the call and redemption, prior to maturity, of
all bonds of Series T so to be called and redeemed pursuant to Section 4.02.
All Series T bonds redeemed pursuant to the provisions hereof shall be canceled
by the Trustee and shall be delivered to or upon the order of the Company, and
shall not be reissued.

     Whenever any Series T bonds are to be redeemed pursuant to Section 4.02,
the Trustee shall allocate to each Registered Owner a proportion of the Series T
bonds to be redeemed, equal, as nearly as practicable, to the proportion that
the principal amount of the Series T bonds then outstanding hereunder,
registered in the name of such Registered Owner, bears to the principal amount
of all Series T bonds then outstanding under the Indenture.

     Redemption notices for Series T bonds shall be given to each Registered
Owner by registered mail and not by publication.  The redemption notice given to
each Registered Owner shall comply with the provisions of Article Fourth of the
Original Indenture and shall also specify (i) the principal amount of such
Registered Owner's Series T

                                       18
<PAGE>

bonds to be redeemed, and (ii) the accrued interest payable in connection with
such redemption.

     Section 4.04.  Redemption at the Holder's Option. For purposes of this
Section 4.04 a "Beneficial Owner" means the person who has the right to sell,
transfer or otherwise dispose of an interest in Series T bonds and the right to
receive the proceeds therefrom, as well as the interest and principal payable to
the Holder thereof. In general, a determination of beneficial ownership in the
Series T bonds will be determined by the Company, in its sole discretion, which
determinations shall be final and binding on all parties.

     Unless the Series T bonds have been declared due and payable prior to their
maturity by reason of an Event of Default, the personal representative or other
Person authorized to represent the estate of the deceased Beneficial Owner or
from a surviving joint tenant(s) or tenant(s) by the entirety (each, a
"Representative") of a deceased Beneficial Owner has the right to request
redemption prior to February 1, 2029 of all or part of such interest, expressed
in integral multiples of $1,000 principal amount, in the Series T bonds, and the
Company will redeem the same subject to the limitations that the Company will
not be obligated to redeem, during the period from the Original Issue Date
through and including February 1, 2000 (the "Initial Period"), and during any
twelve-month period which ends on and includes each February 1 thereafter (each
such twelve-month period being hereinafter referred to as a "Subsequent
Period"), (i) on behalf of a deceased Beneficial Owner any interest in the
Series T bonds which exceeds an aggregate principal amount of $25,000 or (ii)
interests in the Series T bonds in an aggregate principal amount exceeding
$375,000.  A request for redemption in the form attached as Schedule III hereto
may be initiated by the Representative of a deceased Beneficial Owner at any
time and in any principal amount in integral multiples of $1,000.
Representatives of deceased Beneficial Owners must make arrangements with the
Participant through whom such interest is owned in order that timely
presentation of redemption requests can be made by the Participant to the
Trustee.  If the Company, although not obligated to do so, chooses to redeem
interests of any deceased Beneficial Owner in the Series T bonds in the Initial
Period or any Subsequent Period in excess of the $25,000 limitation, such
redemption, to the extent that it exceeds the $25,000 limitation for any
deceased Beneficial Owner, shall not be included in the computation of the
$375,000 limitation for such Initial Period or such Subsequent Period, as the
case may be, or for any succeeding Subsequent Period.  Any Series T bonds (or
portion thereof) tendered pursuant to a redemption request may be withdrawn by a
written request by the Representative received by the Trustee at least ten (10)
days prior to its repayment.

     Subject to the $25,000 and $375,000 limitations, the Company will, after
the death of any Beneficial Owner, redeem the interest of such Beneficial Owner
in the Series T bonds on the next Interest Payment Date following receipt by the
Trustee of a redemption request

                                       19
<PAGE>

received at least twenty (20) days in advance of the next Interest Payment Date.
The Trustee will notify the Company promptly after receipt of any redemption
request and the Company will provide all funds necessary for such redemption
prior to the date of redemption to the Paying Agent. If redemption requests
exceed the aggregate principal amount of interests in Series T bonds required to
be redeemed during the Initial Period or during any Subsequent Period, then such
excess redemption requests will be applied in the order received by the Trustee
to successive Subsequent Periods, regardless of the number of Subsequent Periods
required to redeem such interests. All redemption requests will be redeemed in
the order in which the trustee receives the redemption request. To obtain
repayment pursuant to a redemption request, the Representative must provide to
the Participant (i) a written request for repayment signed by the
Representative, and such signature must be guaranteed by a member firm of a
registered national securities exchange or of the National Association of
Securities Dealers, Inc. ("NASD") or a commercial bank or trust company having
an office or correspondent in the United States, (ii) appropriate evidence
satisfactory to the Company and the Trustee that (A) the Representative has
authority to act on behalf of the deceased Beneficial Owner, (B) the death of
such Beneficial Owner has occurred and (C) the deceased was the owner of a
beneficial interest in such Series T bond at the time of death, (iii) if
applicable, a properly executed assignment or endorsement, and (iv) if the
beneficial interest in such Series T bond is held by a nominee of the deceased
Beneficial Owner, a certificate satisfactory to the Trustee from such nominee
attesting to the deceased's ownership of a beneficial interest in such Series T
bond. The Participant will provide these documents to the Trustee. All questions
as to the eligibility or validity of any exercise of redemption on behalf of a
deceased Beneficial Owner will be determined by the Company, in its sole
discretion, which determinations will be final and binding on all parties.

     For purposes of this Section 4.04, an interest in Series T bonds held in
tenancy by the entirety, joint tenancy or by tenants in common will be deemed to
be held by a single Beneficial Owner and the death of a tenant by the entirety,
joint tenant or tenant in common will be deemed the death of a Beneficial Owner.
The death of a Person who, during his lifetime, was entitled to substantially
all of the rights of a Beneficial Owner of an interest in the Series T bonds
will be deemed the death of the Beneficial Owner, regardless of the recordation
of such interest on the records of the Participant, if such rights can be
established to the satisfaction of the Participant, if any, and the Company.

     In the case of any redemption request which is presented pursuant to this
Section 4.04 and which has not been fulfilled at the time the Company gives
notice of its election to partially redeem Series T bonds pursuant to Section
4.02 hereof, such interest or portion thereof shall not be subject to redemption
pursuant to such Section

                                       20
<PAGE>

4.02, but shall remain subject to redemption pursuant to this Section 4.04.


                                 ARTICLE FIFTH
                         SPECIAL INSURANCE PROVISIONS

     Section 5.01.  Insurer as Third Party Beneficiary. To the extent that the
Indenture confers upon or gives or grants to the Insurer any right, remedy or
claim, the Insurer is hereby explicitly recognized as being a third-party
beneficiary hereunder and may enforce any such right remedy or claim conferred,
given or granted hereunder.

     Section 5.02.  Notices and Information.

          (a)  The Company shall furnish to the Insurer:

          (i)  Any notice that is required to be given to a Holder of the Series
          T bonds or to the Trustee pursuant to the Indenture.

          (ii) As soon as practicable after the filing thereof, a copy of any
          financial statement of the Company and a copy of any audit and annual
          report of the Company; a copy of any notice to be given to the
          Registered Owners of the Series T bonds including, without limitation,
          notice of any redemption of or defeasance of the Series T bonds; and
          such additional information as it may reasonably request.

          (b)  The Company will permit the Insurer to have access to and to make
copies of all books and records relating to the Series T bonds at any reasonable
time.

          (c)  Notwithstanding any other provision of the Indenture, the Trustee
and the Company shall immediately notify the Insurer in accordance with Section
5.06 if at any time after such amounts are due to be paid to the Trustee or
Paying Agent there are insufficient moneys to make any payments of principal
and/or interest as required and promptly upon the occurrence of any Event of
Default hereunder.

     All notices and information required to be given to the Insurer shall be in
writing and shall be sent by overnight delivery to MBIA Insurance Corporation,
113 King Street, Armonk, New York 10504.

     Section 5.03.  Concerning the Special Insurance Provisions. The provisions
of this Article V shall apply notwithstanding anything in the Indenture to the
contrary, but only so long as the Policy shall be in full force and effect and
the Insurer is not in default thereunder.

     Section 5.04.  Amendments. Any provision of the Indenture may not be
amended in any manner which materially adversely affects the rights of the
Insurer hereunder without the prior written consent of the

                                       21
<PAGE>

Insurer, which shall not be unreasonably withheld, conditioned or delayed.

          Section 5.05.  Limitation on Defeasance. Notwithstanding anything
herein to the contrary, in the event that the principal and/or interest due on
the Series T bonds shall be paid by the Insurer pursuant to the Policy, the
Series T bonds shall remain outstanding for all purposes, not be defeased or
otherwise satisfied and not be considered paid by the Company, and the
assignment and pledge of moneys held in trust by the Trustee and all covenants,
agreements and other obligations of the Company to the Registered Owners shall
continue to exist and shall run to the benefit of the Insurer, and the Insurer
shall be subrogated to the rights of such Registered Owners.

          Section 5.06.  Payments Under the Policy.

          (a)  If, as of the second day next preceding any date on which payment
of principal of or interest on the Series T bonds is due, there are insufficient
moneys available under the Indenture to pay all principal and interest coming
due on the Series T bonds on the next succeeding payment date, the Trustee shall
immediately notify the Insurer or its designee by telephone or telegraph,
confirmed in writing by registered or certified mail, of the amount of the
deficiency.

          (b)  If the deficiency is made up in whole or in part prior to or on
the Interest Payment Date or the date designated for the payment of principal of
the Series T bonds, the Trustee shall so notify the Insurer or its designee.

          (c)  In addition, if the Trustee has notice that any of the Registered
Owners have been required to disgorge payments of principal or interest on
Series T bonds to the Company or to the trustee in bankruptcy for creditors or
others pursuant to a final judgment by a court of competent jurisdiction that
such payment constitutes a voidable preference to such Registered Owners within
the meaning of any applicable bankruptcy laws, then the Trustee shall notify the
Insurer or its designee of such fact by telephone or telegraphic notice,
confirmed in writing by registered or certified mail.

          (d)  The Trustee is hereby irrevocably designated, appointed, directed
and authorized to act as attorney-in-fact for Registered Owners of the Series T
bonds as follows:

               (i) if and to the extent there is a deficiency in amounts
          required to pay interest on the Series T bonds, the Trustee shall (A)
          execute and deliver to State Street Bank and Trust Company, N.A., or
          its successors under the Policy (the "Insurance Paying Agent"), in
          form satisfactory to the Insurance Paying Agent, an instrument
          appointing the Insurer as agent for such Registered Owners in any
          legal proceeding related to the payment of such interest and an
          assignment to the Insurer of the claims for

                                       22
<PAGE>

          interest to which such deficiency relates and which are paid by the
          Insurer, (B) receive as designee of the respective Registered Owners
          (and not as Trustee) in accordance with the tenor of the Policy
          payment from the Insurance Paying Agent with respect to the claims for
          interest so assigned and (C) disburse the same to such respective
          Registered Owners; and

               (ii) if and to the extent of a deficiency in amounts required to
          pay principal of the Series T bonds, the Trustee shall (A) execute and
          deliver to the Insurance Paying Agent an instrument appointing the
          Insurer as agent for such Registered Owner in any legal proceeding
          relating to the payment of such principal and an assignment to the
          Insurer of any of the Series T bonds surrendered to the Insurance
          Paying Agent of so much of the principal amount thereof as has not
          previously been paid or for which moneys are not held by the Trustee
          and available for such payment (but such assignment shall be delivered
          only if payment from the Insurance Paying Agent is received), (B)
          receive as designee of the respective Registered Owners (and not as
          Trustee) in accordance with the tenor of the Policy payment therefor
          from the Insurance Paying Agent and (C) disburse the same to such
          Registered Owners.

          (e)  Payments with respect to claims for interest on and principal of
Series T bonds disbursed by the Trustee from proceeds of the Policy shall not be
considered to discharge the obligation of the Company with respect to such
Series T bonds as set forth in Section 2.01 hereof, and the Insurer shall become
the owner of such unpaid Series T bond and claims for interest in accordance
with the tenor of the assignment made to it under the provisions of this
subsection or otherwise.

          (f)  Irrespective of whether any such assignment is executed and
delivered, the Company and the Trustee hereby agree for the benefit of the
Insurer that:

               (i)  they recognize that to the extent the Insurer makes
          payments, directly or indirectly (as by paying through the Trustee),
          on account of principal of or interest on the Series T bonds, the
          Insurer will be subrogated to the rights of such Registered Owners to
          receive the amount of such principal and interest from the Company,
          with interest thereon as provided and solely from the sources stated
          in the Indenture and the Series T bonds; and

               (ii) they will accordingly pay to the Insurer the amount of such
          principal and interest (including principal and interest recovered
          under subparagraph (ii) of the first paragraph of the Policy, which
          principal and interest shall be deemed past due and not to have been
          paid), with interest thereon as provided in the Indenture and the
          Series T bond, but only from the sources and in the manner provided
          herein for the payment of principal of and

                                       23
<PAGE>

          interest on the Series T bonds to Registered Owners and will otherwise
          treat the Insurer as the owner of such rights to the amount of such
          principal and interest.

          Section 5.07.  Insurer's Rights Concerning the Trustee.

          (a)  The Insurer shall receive prompt written notice of any Trustee or
Paying Agent resignation.

          (b)  Notwithstanding any other provision of the Indenture, in
determining whether the rights of the Holders of Series T bonds will be
adversely affected in any material respect by any action taken pursuant to the
terms and provisions of the Indenture, the Trustee or Paying Agent shall
consider the effect on the Holders of Series T bonds as if there were no Policy.

          Section 5.08.  Insurer's Right to Accelerate, etc.  Anything in the
Indenture to the contrary notwithstanding, upon the occurrence and continuance
of an Event of Default, so long as the Policy shall be in full force and effect
and the Insurer is not in default under the terms of the Policy, the Insurer
shall be entitled to control and direct the enforcement of all rights and
remedies granted to the Holders of Series T bonds.


                                 ARTICLE SIXTH
           PARTICULAR PROVISIONS RELATED TO THE TRUST INDENTURE ACT

          Anything contained elsewhere in the Indenture notwithstanding, so long
as any of the Series T bonds shall remain outstanding, the following provisions,
which are intended to clarify certain matters, including compliance with the
TIA, shall apply, in addition to all other provisions of the Indenture, as
supplemented, and in the case of any conflict with any other provision of the
Indenture, the following provisions shall control.

          Section 6.01.  Deposited Moneys to be Held in Trust by Trustee.
Subject to Section 6.03, all moneys deposited with the Trustee pursuant to
Section 66 of the Original Indenture, shall be held in trust and applied by it
to the payment, either directly or through any Paying Agent (including the
Company if acting as its own Paying Agent), to the Registered Owners of the
particular Series T bonds for the payment or redemption of which such moneys
have been deposited with the Trustee of all sums due and to be come due thereon
for principal and interest.

          Section 6.02.  Paying Agent to Repay Moneys Held.  Upon the
satisfaction and discharge of the Indenture, all moneys then held by any Paying
Agent for the Series T bonds (other than the Trustee) shall, upon written demand
by the Company, be repaid to the Company or paid to the Trustee, and thereupon
such Paying Agent shall be released from all further obligations with respect to
such moneys.

                                       24
<PAGE>

     Section 6.03.  Return of Unclaimed Moneys. Any moneys deposited with or
paid to the Trustee for payment of the principal of or any interest on any
Series T bonds and not applied but remaining unclaimed by the Registered Owners
of such Series T bonds for two years after the date upon which the principal of
or any interest on such Series T bonds, as the case may be, shall have become
due and payable, shall be repaid to the Company, subject to applicable abandoned
property laws, by the Trustee on written demand by the Company; and any
Registered Owner of any of such Series T bonds shall thereafter look only to the
Company for any payment which such Registered Owner may be entitled to collect.

     Section 6.04.  Provisions as to Paying Agent. The Trustee shall be the
Paying Agent for the Series T bonds and, at the option of the Company, the
Company may appoint additional Paying Agents (including without limitation
itself). Whenever the Company shall appoint a Paying Agent other than the
Trustee with respect to the Series T bonds, it will cause such Paying Agent to
execute and deliver to the Trustee an instrument in which such agent shall agree
with the Trustee, subject to the provisions of this Section:

     (a)  that such Paying Agent will hold all sums received by it as such agent
for the payment of the principal of or interest, if any, on the Series T bonds
(whether such sums have been paid to it by the Company or by any other obligor
on the Series T bonds) in trust for the benefit of the Registered Owners of the
Series T bonds, or of the Trustee until such sums shall be paid to such
Registered Owners or otherwise disposed of as herein provided;

     (b)  that such Paying Agent will give the Trustee notice of any failure by
the Company (or by any other obligor on the Series T bonds) to make any payment
of the principal of, premium if any, or interest on the Series T bonds when the
same shall be due and payable; and

     (c)  that such Paying Agent will at any time during the continuance of any
such failure, upon the written request of the Trustee, forthwith pay to the
Trustee all sums so held in trust by such Paying Agent.

     The Company will, on or prior to each due date of the principal of and any
interest on the Series T bonds, deposit with the Paying Agent a sum sufficient
to pay such principal and any interest so becoming due, such sum to be held in
trust for the benefit of the Registered Owners of the Series T bonds entitled to
such principal of and any interest, and (unless such Paying Agent is the
Trustee) the Company will promptly notify the Trustee of any failure to take
such action.

     If the Company shall act as its own Paying Agent with respect to the Series
T bonds, it will, on or before each due date of the principal of or interest, if
any, on the Series T bonds, set aside,

                                       25
<PAGE>

segregate and hold in trust for the benefit of the Registered Owners of the
Series T bonds, a sum sufficient to pay such principal or interest, if any, so
becoming due until such sums shall be paid to such Registered Owners or
otherwise disposed of as herein provided. The Company will promptly notify the
Trustee of any failure to take such action.

     The Company may at any time pay or cause to be paid to the Trustee all sums
held in trust by it or any Paying Agent hereunder, as required by this Section,
such sums to be held by the Trustee upon the trusts herein contained, and, upon
such payment by any Paying Agent to the Trustee, such Paying Agent shall be
released from all further liability with respect to such money.

     Anything in this Section to the contrary notwithstanding, the agreement to
hold sums in trust as provided in this section is subject to the provisions of
Sections 6.02 and 6.03.

     Section 6.05.  Certificates and Notice to Trustee.  The Company shall, on
or before the expiration of ninety (90) days after the end of each calendar year
ending on or after December 31, 1999, deliver to the Trustee a certificate from
its principal executive officer, principal financial officer or principal
accounting officer covering the preceding calendar year and stating whether or
not, to the knowledge of such Person, the Company has complied with all
conditions and covenants under the Indenture, and, if not, describing in
reasonable detail any failure by the Company to comply with any such conditions
or covenants.  For purposes of this Section, compliance shall be determined
without regard to any period of grace or requirement of notice provided under
the Indenture.  Upon the occurrence of a default, the Company shall promptly
notify the Trustee of such event.

     Section 6.06.  Company to Furnish Registered Owner Lists.  The Company and
any other obligor on the Series T bonds shall furnish or cause to be furnished
to the Trustee a list in such form as the Trustee may reasonably require of the
names and addresses of the Registered Owners of the Series T bonds:

     (a)  semi-annually and not more than fifteen (15) days after each Regular
Record Date for each Interest Payment Date that is not a maturity date, as of
such Regular Record Date, and such list need not include information received
after such date; and

     (b)  at such other times as the Trustee may request in writing, within
thirty (30) days after receipt by the Company of any such request, as of a date
not more than fifteen (15) days prior to the time such information is furnished,
and such list need not include information received after such date; provided
that if and so long as the Trustee shall be the registrar for the Series T
bonds, such list shall not be required to be furnished.

                                       26
<PAGE>

     Section 6.07.  Preservation and Disclosure of Registered Owner Lists.

     (a)  The Trustee shall preserve, in as current a form as is reasonably
practicable, all information as to the names and addresses of the Registered
Owners of the Series T bonds (i) contained in the most recent lists furnished to
it as provided in Section 6.06, (ii) received by it in the capacity of registrar
for the Series T bonds, if so acting, and (iii) filed with it within the two
preceding years pursuant to Section 6.09(d)(ii).  The Trustee may destroy any
list furnished to it as provided in Section 6.06 upon receipt of a new list so
furnished.

     (b)  In case three or more Registered Owners of Series T bonds (hereinafter
referred to as "applicants") apply in writing to the Trustee and furnish to the
Trustee reasonable proof that each such applicant has owned a Series T bond for
a period of at least six months preceding the date of such application, and such
application states that the applicants desire to communicate with other
Registered Owners of Series T bonds with respect to their rights under this
Indenture or under the Series T bonds and such application is accompanied by a
copy of the form of proxy or other communication which such applicants propose
to transmit, then the Trustee shall, within five Business Days after the receipt
of such application, at its election, either

               (i)  afford to such applicants access to the information
          preserved at the time by the Trustee in accordance with the provisions
          of subsection (a) of this Section; or

               (ii) inform such applicants as to the approximate number of
          Registered Owners whose names and addresses appear in the information
          preserved at the time by the Trustee, in accordance with the
          provisions of such subsection (a) and as to the approximate cost of
          mailing to such Registered Owners the form of proxy or other
          communication, if any, specified in such application.

     If the Trustee shall elect not to afford to such applicants access to such
information, the Trustee shall, upon the written request of such applicants,
mail to each Registered Owner of Series T bonds, whose name and address appears
in the information preserved at the time by the Trustee in accordance with the
provisions of such subsection (a) a copy of the form of proxy or other
communication which is specified in such request, with reasonable promptness
after a tender to the Trustee of the material to be mailed and of payment, or
provision for the payment, of the reasonable expenses of mailing, unless within
five (5) days after such tender the Trustee shall mail to such applicants and
file with the Commission, together with a copy of the material to be mailed, a
written statement to the effect that, in the opinion of the Trustee, such
mailing would be contrary to the

                                       27
<PAGE>

best interests of the Registered Owners or would be in violation of applicable
law. Such written statement shall specify the basis of such opinion. If the
Commission, after opportunity for a hearing upon the objections specified in the
written statement so filed, shall enter an order refusing to sustain any of such
objections or if, after the entry of an order sustaining one or more of such
objections, the Commission shall find, after notice and opportunity for hearing,
that all the objections so sustained have been met, and shall enter an order so
declaring, the Trustee shall mail copies of such material to all such Registered
Owners with reasonable promptness after the entry of such order and the renewal
of such tender; otherwise the Trustee shall be relieved of any obligation or
duty to such applicants respecting their application.

     (c)  Each and every Registered Owner of a Series T bond, by receiving and
holding the same, agrees with the Company and the Trustee that neither the
Company nor the Trustee nor the agent of the Company or the Trustee shall be
held accountable by reason of the disclosure of any such information as to the
names and addresses of the Registered Owners of Series T bonds in accordance
with the provisions of subsection (b) of this Section, regardless of the source
from which such information was derived, and that the Trustee shall not be held
accountable by reason of mailing any material pursuant to a request made under
such subsection (b).

     Section 6.08.  Reports by the Company.  The Company shall:

     (a)  file with the Trustee, within fifteen (15) days after the Company is
required to file the same with the Commission, copies of the annual reports and
of the information, documents and other reports (or copies of such portions of
any of the foregoing as the Commission may from time to time by rules and
regulations prescribe) which the Company may be required to file with the
Commission pursuant to Section 13 or Section 15(d) of the Securities Exchange
Act of 1934; or, if the Company is not required to file information, documents
or reports pursuant to either of said Sections, then it will file with the
Trustee and the Commission, in accordance with rules and regulations prescribed
from time to time by the Commission, such of the supplementary and periodic
information, documents and reports which may be required pursuant to Section 13
of the Securities Exchange Act of 1934 in respect of a security listed and
registered on a national securities exchange as may be prescribed from time to
time in such rules and regulations;

     (b)  file with the Trustee and the Commission, in accordance with rules and
regulations prescribed from time to time by the Commission, such additional
information, documents and reports with respect to compliance by the Company
with the conditions and covenants of this Indenture as may be required from time
to time by such rules and regulations; and

                                       28
<PAGE>

     (c)  transmit by mail to all Registered Owners of Series T bonds, within
thirty (30) days after the filing thereof with the Trustee in the manner and to
the extent provided in Section 6.09(d), such summaries of any information,
documents and reports required to be filed by the Company pursuant to paragraphs
(a) and (b) of this Section as may be required by rules and regulations
prescribed from time to time by the Commission.

     Section 6.09.  Reports by the Trustee.

     (a)  Annually, not later than August 15 of each year, the Trustee shall
transmit by mail in the manner provided in Section 6.22 a brief report dated as
of such date that complies with Section 313(a) of the TIA (to the extent
required by such Section).

     (b)  The Trustee shall from time to time transmit by mail brief reports
that comply, both in content and date of delivery, with Section 313(b) of the
TIA (to the extent required by such Section).

     (c)  A copy of each such report mailed pursuant to this section shall, at
the time of such transmission to such Registered Owners, be filed by the Trustee
with each stock exchange upon which any Series T bonds are listed and also with
the Commission.  The Company will notify the Trustee promptly in writing upon
the listing of such Series T bonds on any stock exchange.

     (d)  Reports pursuant to this Section shall be transmitted:

          (i)   by mail to all Registered Owners of Series T bonds, as their
          names and addresses appear in the register for the Series T bonds;

          (ii)  by mail to such Registered Owners of Series T bonds as have
          within the two years preceding such transmission, filed their names
          and addresses with the Trustee for such purpose;

          (iii) by mail, except in the case of reports pursuant to Section
          6.09(b) and (c) hereof, to all Registered Owners of Series T bonds
          whose names and addresses have been furnished to or received by the
          Trustee pursuant to Section 6.06 and 6.07(a) (ii) hereof; and

          (iv)  at the time such report is transmitted to the Registered Owners
          of the Series T bonds, to each exchange on which Series T bonds are
          listed and also with the Commission.

     Section 6.10.  Prohibition of Impairment of Registered Owner's Right to
Payment.  Notwithstanding any other provision in the Indenture, the rights of
any Registered Owner of any Series T bond to receive payment of the principal of
and any interest on a Series T bond, on or after the respective due dates
expressed in a Series T

                                       29
<PAGE>

bond or on the applicable Redemption Date, or to institute suit for the
enforcement of any such payment on or after such respective dates are absolute
and unconditional, and shall not be impaired or affected without the consent of
such Registered Owner.

     Section 6.11.  Notice of Default. The Trustee shall, within ninety (90)
days after the occurrence of a default with respect to the Series T bonds, give
to all Registered Owners of the Series T bonds, in the manner provided in
Section 6.22, notice of such default known to the Trustee, unless such default
shall have been cured or waived before the giving of such notice, the term
"default" for the purpose of this Section 6.11 being hereby defined to be any
event which is or after notice or lapse of time or both would become an Event of
Default; provided that, except in the case of default in the payment of the
principal of or any premium or interest on any of the Series T bonds, or in the
payment of any sinking or purchase fund installments, the Trustee shall be
protected in withholding such notice if and so long as its board of directors or
trustees, executive committee, or a trust committee of directors or trustees or
Responsible Officers in good faith determines that the withholding of such
notice is in the interests of the Registered Owners of the Series T bonds.

     Section 6.12.  Undertaking to Pay Costs. All parties to this Twentieth
Supplemental Indenture agree, and each Registered Owner of any Series T bond by
acceptance thereof shall be deemed to have agreed, that any court may in its
discretion require, in any suit for the enforcement of any right or remedy under
the Indenture (including this Twentieth Supplemental Indenture) or in any suit
against the Trustee for any action taken, suffered or omitted by it as Trustee,
the filing by any party litigant in such suit of an undertaking to pay the costs
of such suit, and that such court may in its discretion assess reasonable costs,
including reasonable attorneys' fees, against any party litigant in such suit,
having due regard to the merits and good faith of the claims or defenses made by
such party litigant; but this Section 6.12 shall not apply to any suit
instituted by the Trustee, or to any suit instituted by any Registered Owner, or
group of Registered Owners, holding in the aggregate more than 10% in principal
amount of the Series T bonds outstanding, or to any suit instituted by any
Registered Owner for the enforcement of the payment of the principal of or any
interest on any Series T bond on or after the due date expressed in such Series
T bond or the applicable Redemption Date.

     Section 6.13.  Conflicting Interest of Trustee. The Trustee shall be
subject to and shall comply with the provisions of Section 310(b) of the TIA.
Nothing in this Twentieth Supplemental Indenture shall be deemed to prohibit the
Trustee or the Company from making any application permitted pursuant to such
section.

     Section 6.14.  Existence and Eligibility of Trustee. There shall at all
times be a Trustee hereunder which Trustee shall at all times be a corporation
organized and doing business under the laws of the

                                       30
<PAGE>

United States or any State thereof or of the District of Columbia having (or in
the case of a subsidiary of a bank holding company, its parent shall have) a
combined capital and surplus of at least $50,000,000 and which is authorized
under such laws to exercise corporate trust powers and is subject to supervision
or examination by Federal or State authorities. Such corporation shall have its
principal place of business in the Borough of Manhattan, The City of New York,
State of New York or the City of Boston, Commonwealth of Massachusetts, if there
be such a corporation in such location willing to act upon reasonable and
customary terms and conditions. If such corporation publishes reports of
condition at least annually, pursuant to law or to the requirements of the
aforesaid authority, then for the purposes of this Section 6.14, the combined
capital and surplus shall be deemed to be as set forth in its most recent report
of condition so published. No obligor upon the Series T bonds or Person directly
or indirectly controlling, controlled by, or under common control with such
obligor shall serve as Trustee. If at any time the Trustee shall cease to be
eligible in accordance with this Section 6.14, the Trustee shall resign
immediately in the manner and with the effect specified herein.

     Section 6.15.  Resignation or Removal of Trustee.

     (a)  Pursuant to the provisions of this Twentieth Supplemental Indenture,
the Trustee may at any time resign and be discharged of the trusts created by
the Indenture by giving written notice to the Company specifying the day upon
which such resignation shall take effect, and such resignation shall take effect
immediately upon the later of the appointment of a successor trustee and such
day.

     (b)  Any Trustee may be removed at any time by an instrument or concurrent
instruments in writing filed with such Trustee and signed and acknowledged by
the Registered Owners of a majority in principal amount of the then outstanding
First Mortgage Bonds or by their attorneys in fact duly authorized.

     (c)  So long as no default has occurred and is continuing, and no event has
occurred and is continuing that, with the giving of notice or the lapse of time
or both, would become a default, the Company may remove any Trustee upon written
notice to the Registered Owner of each Series T bond outstanding and the Trustee
and appoint a successor Trustee meeting the requirements of Section 6.14.  The
Company or the successor Trustee shall give notice to the Registered Owners, in
the manner provided in Section 6.22, of such removal and appointment within
thirty (30) days of such removal and appointment.

     (d)  If at any time (i) the Trustee shall cease to be eligible in
accordance with Section 6.14 hereof and shall fail to resign after a written
request therefor by the Company or by any Registered Owner who has been a bona
fide Registered Owner for at least six months, (ii) the Trustee shall fail to
comply with Section 6.13 hereof after written request therefor by the Company or
any such Registered Owner,

                                       31
<PAGE>

or (iii) the Trustee shall become incapable of acting or shall be adjudged a
bankrupt or insolvent or a receiver of the Trustee or its property shall be
appointed or any public officer shall take charge or control of the Trustee or
of its property or affairs for the purpose of rehabilitation, conservation or
liquidation, then the Trustee may be removed forthwith by an instrument or
concurrent instruments in writing filed with the Trustee and either:

               (i)  signed by the President or any Vice President of the Company
          and attested by the Secretary or an Assistant Secretary of the
          Company; or

               (ii) signed and acknowledged by the Registered Owners of a
          majority in principal amount of outstanding Series T bonds or by their
          attorneys in fact duly authorized.

     (e)  Any resignation or removal of the Trustee shall not become effective
until acceptance of appointment by the successor Trustee as provided in Section
6.16 hereof.

     Section 6.16.  Appointment of Successor Trustee.

          (a)  If at any time the Trustee shall resign or be removed, the
Company, by a resolution of its Board of Directors, shall promptly appoint a
successor Trustee.

          (b)  The Company shall provide written notice of its appointment of a
successor Trustee to the Registered Owner of each Series T bond outstanding
following any such appointment.

          (c)  If no appointment of a successor Trustee shall be made pursuant
to Section 6.16(a) hereof within sixty (60) days after appointment shall be
required, any Registered Owner or the resigning Trustee may apply to any court
of competent jurisdiction to appoint a successor Trustee. Said court may
thereupon after such notice, if any, as such court may deem proper and
prescribe, appoint a successor Trustee.

          (d)  Any Trustee appointed under this Section 6.16 as a successor
Trustee shall be a bank or trust company eligible under Section 6.14 hereof and
qualified under Section 6.13 hereof.

     Section 6.17.  Acceptance by Successor Trustee.

          (a)  Any successor Trustee appointed as provided in Section 6.16
hereof shall execute, acknowledge and deliver to the Company and to its
predecessor Trustee an instrument accepting such appointment hereunder, and
thereupon the resignation or removal of the predecessor Trustee shall become
effective and such successor Trustee, without any further act, deed or
conveyance, shall become vested with all the rights, powers, duties and
obligations of its predecessor hereunder, with like effect as if originally
named as Trustee herein; but
                                       32
<PAGE>

nevertheless, on the written request of the Company or of the successor Trustee,
the Trustee ceasing to act shall, upon payment of any amounts then due it
pursuant to Section 77 of the Original Indenture, execute and deliver an
instrument transferring to such successor Trustee all the rights and powers of
the Trustee so ceasing to act, including all right, title, and interest in the
First Mortgage Bonds. Upon request of any such successor Trustee, the Company
shall execute any and all instruments in writing in order more fully and
certainly to vest in and confirm to such successor Trustee all such rights and
powers. Any Trustee ceasing to act shall, nevertheless, retain a lien upon all
property or funds held or collected by such Trustee to secure any amounts then
due it pursuant to Section 77 of the Original Indenture.

          (b)  No successor Trustee shall accept appointment as provided in this
Section 6.17 unless at the time of such acceptance such successor Trustee shall
be qualified under Section 6.13 hereof and eligible under Section 6.14 hereof
and the Insurer shall have consented in writing to such appointment, which
consent shall not be unreasonably withheld, conditioned or delayed.

          (c)  Upon acceptance of appointment by a successor Trustee as provided
in this Section 6.17, the successor Trustee shall mail notice of its succession
hereunder to all Registered Owners of Series T bonds as the names and addresses
of such Registered Owners appear on the books of the Trustee kept for that
purpose.

     Section 6.18.  Limitations on Rights of Trustee as a Creditor.  The Trustee
shall be subject to, and shall comply with, the provisions of Section 311 of the
TIA.

     Section 6.19.  Company-Owned Series T Bonds Disregarded.  In determining
whether the Registered Owners of the requisite aggregate principal amount of
outstanding Series T bonds have concurred in any direction, consent or waiver
under the Indenture, Series T bonds which are owned by the Company or any other
obligor on the Series T bonds or by any person directly or indirectly
controlling or controlled by or under direct or indirect common control with the
Company or any other obligor on the Series T bonds shall be disregarded and
deemed not to be outstanding for the purpose of any such determination; provided
that, for the purposes of determining whether the Trustee shall be protected in
relying on any such direction, consent or waiver, only Series T bonds which the
Trustee knows are so owned shall be so disregarded.  Series T bonds so owned
which have been pledged in good faith to third parties may be regarded as
outstanding for the purposes of this Section 6.19 if the pledgee shall establish
the pledgee's right to take action with respect to such Series T bonds and that
the pledgee is not a person directly or indirectly controlling or controlled by
or under direct or indirect common control with the Company or any such other
obligor.  In the case of a dispute as to such right, the Trustee may rely upon
an opinion of counsel (which may

                                       33
<PAGE>

be counsel to the Company) and Officers' Certificate to establish the foregoing.

     Section 6.20.   Business Days.  Unless otherwise provided, in any case
where the date of maturity of the principal of or any interest on any Series T
bond or the date fixed for redemption of any Series T bond is not a Business
Day, then payment of such principal or any interest need not be made on such
date but may be made on the next succeeding Business Day with the same force and
effect as if made on the date of maturity or the date fixed for redemption, and,
in the case of timely payment thereof, no interest shall accrue for the period
from and after such Interest Payment Date or the date on which the principal of
the Series T bond is required to be paid.

     Section 6.21.  Trust Indenture Act to Control.  If and to the extent that
any provision of the Indenture limits, qualifies or conflicts with the duties
imposed by the TIA, such required provision of the TIA shall govern.

                                       34
<PAGE>

     Section 6.22.  Manner of Mailing Notice to Registered Owner.

     (a)  Any notice or demand which by any provision of the Indenture is
required or permitted to be given or served by the Trustee or the Company to or
on the Registered Owners of Series T bonds as the case may be, shall be given or
served by first-class mail, postage prepaid, addressed to the Registered Owners
of such Series T bonds in the register of Registered Owners, and any such notice
shall be deemed to be given or served by being deposited in a post office letter
box in the form and manner provided in this Section 6.22.  In case by reason of
the suspension of regular mail service or by reason of any other cause it shall
be impracticable to give notice to any Registered Owner by mail, then such
notification to such Registered Owner as shall be made with the approval of the
Trustee shall constitute a sufficient notification for every purpose hereunder.

     (b)  The Company shall also provide any notices required under the
Indenture by publication, but only to the extent that such publication is
required by the TIA, the rules and regulations of the Commission or any
securities exchange upon which any Series T bonds are listed.


                                ARTICLE SEVENTH
                             ADDITIONAL PROVISIONS

     Section 7.01.  Title.  The Company covenants and agrees that it has good
right and lawful authority to mortgage the properties described in the granting
clauses hereof and after-acquired property as provided herein and that it is
lawfully seized and possessed of the same (except with respect to after-acquired
property).

     Section 7.02.  Released Property.  The Company covenants and agrees that
since the date of the Nineteenth Supplemental Indenture no real estate or
interest therein has been taken by exercise of the right of eminent domain or
released from the Indenture or subjected to any easement which has not been
terminated of record except as listed on the "Schedule of Released Property"
attached hereto as Schedule II.

     Section 7.03.  Bonds Held by the Company.  No bonds owned or held by, for
the account of or for the benefit of the Company or any other obligor on the
bonds (other than bonds pledged to secure an obligation) shall be deemed
entitled to share in any payment or distribution provided in Article Sixth of
the Original Indenture or under the Policy, provided that the Trustee shall be
protected in making any such payment or distribution unless it shall have actual
knowledge that the bonds in respect of which such payment or distribution is
made are so owned or held.

     Section 7.04.  Payment of Series T Bonds.  Payment of the principal and
interest on all Series T bonds shall be payable as follows:

                                       35
<PAGE>

     (a)  On or before 9:30 a.m., Boston, Massachusetts time, or such other time
as shall be agreed upon between the Trustee and the Company, of the day on which
payment of principal or interest is due on any Global Note pursuant to the terms
thereof, the Company shall deliver to the Trustee funds available on such date
sufficient to make such payment, by wire transfer of immediately available funds
or by instructing the Trustee to withdraw sufficient funds from an account
maintained by the Company with the Trustee or such other method as is acceptable
to the Trustee.  On or before 12:00 noon, Boston, Massachusetts time, or such
other time as shall be agreed upon between the Trustee and the Depository, of
the day on which any payment of interest is due on any Global Note (other than
at maturity), the Trustee shall pay to the Depository such interest in same day
funds.  On or before 1:00 p.m., Boston, Massachusetts time or such other time as
shall be agreed upon between the Trustee and the Depository, of the day on which
principal and interest payable at maturity, if any, is due on any Global Note,
the Trustee shall deposit with the Depository the amount equal to the principal
and interest payable at maturity by wire transfer into the account specified by
the Depository.  As a condition to the payment, at maturity or upon redemption,
of any part of the principal of and interest on any Global Note, the Depository
shall surrender, or cause to be surrendered, such Global Note to the Trustee,
whereupon a new Global Note shall be issued to the Depository pursuant to
Section 3.04(e) hereof.

     (b)  With respect to any Note that is not a Global Note, principal and
interest due at the maturity of the Note shall be payable in immediately
available funds when due upon presentation and surrender of such Note at the
Corporate Trust Office of the Trustee or at the authorized office of any Paying
Agent.  Interest on any Note that is not a Global Note (other than interest
payable at maturity) shall be paid by check mailed to the Registered Owner
thereof at such Registered Owner's address as it appears on the register by
check payable in clearinghouse funds; provided that if the Trustee receives a
written request from any Registered Owner of Notes, the aggregate principal
amount of which having the same Interest Payment Date equals or exceeds
$10,000,000, on or before the applicable Regular Record Date for such Interest
Payment Date, interest shall be paid by wire transfer of immediately available
funds to a bank within the continental United States designated by such
Registered Owner in its request or by direct deposit into the account of such
Registered Owner designated by such Registered Owner in its request if such
account is maintained with the Trustee or any paying agent.

     Section 7.05.  Events of Default.  Anything contained elsewhere in the
Indenture notwithstanding, and without limiting the effect of Section 7.12 of
this Twentieth Supplemental Indenture, so long as any of the Series T bonds
shall remain outstanding, the Trustee shall be entitled to exercise any of the
remedies provided in the Indenture (including, without limitation, the remedies
provided in Sections 33, 46, 47, 48 and 49 of the Original Indenture):


                                       36
<PAGE>

     (a)  if the Company shall default in the payment of any interest payable on
any Series T bonds and such default shall have continued for a period of ninety
(90) days, or the Company shall default in the payment of principal on any
Series T bonds at final maturity or at any date fixed for the optional
redemption thereof pursuant to the provisions of Section 4.02 or Section 4.03 of
this Twentieth Supplemental Indenture;

     (b)  if the Company shall fail in the observance or performance of any
other covenant, condition or agreement not enumerated in this Section herein
above, contained in the Indenture (including this Twentieth Supplemental
Indenture), and such failure shall continue for a period of ninety (90) days
after the date on which written notice specifying such failure, stating that
such notice is a "Notice of Default" hereunder and demanding that the Company
remedy the same, shall have been given to the Company by the Trustee by
registered or certified mail, or to the Company and the Trustee by the
Registered Owners of not less than 10% in aggregate principal amount of the
Series T bonds; or

     (c)  in the event of the entry of a decree or order by a court having
jurisdiction in the premises adjudging the Company a bankrupt or insolvent, or
approving as properly filed a petition seeking reorganization, arrangement,
adjustment or composition of, or in respect of, the Company under applicable
Federal bankruptcy law or any other applicable Federal or State law, or
appointing a receiver, liquidator, assignee, trustee, sequestrator (or other
similar official) or the Company or of any substantial part of its property, or
ordering the winding up or liquidation of its affairs, and the continuance of
any such decree or order unstayed and in effect for a period of sixty (60)
consecutive days; or

     (d)  in the event of the institution by the Company of proceedings to be
adjudicated a bankrupt or insolvent, or the consent by it to the institution of
bankruptcy or insolvency proceedings against it, or the filing by it of a
petition or answer or consent seeking reorganization or relief under applicable
Federal bankruptcy law or any other similar applicable Federal or State law, or
the consent by it to the filing of any such petition or the appointment of a
receiver, liquidator, assignee, trustee, sequestrator (or other similar
official) of the Company or of any substantial part of its property, or the
making by it of an assignment for the benefit of creditors, or the admission by
it in writing of its inability to pay its debts generally as they become due.

      Section 7.06.  Expiration. This Twentieth Supplemental Indenture shall
become void when the Original Indenture shall be void and the Insurer has been
repaid in full any amounts paid by the Insurer under the Policy.

                                       37
<PAGE>

      Section 7.07.  Dates for Identification.  Dates of supplemental indentures
and of bonds are intended as and for dates for the identification of such bonds
and such instruments, respectively, and are not intended to indicate that any
such instrument or any bond was and no such instrument or bond has been or is to
be executed on a Sunday or a legal holiday, the respective dates when
supplemental indentures were executed being the dates or respective dates of the
acknowledgments of the parties thereto.

      Section 7.08.  Section References.  Whenever reference is made in this
Twentieth Supplemental Indenture to a Section or an Article of the Original
Indenture and such Section or Article has been amended by this instrument or any
of the indentures supplemental to the Original Indenture enumerated herein
above, or two or more of them, then such reference shall be to such Section or
Article as so amended, whether or not herein expressly so stated.

      Section 7.09.  Recordation.  The Company, at its own cost and expense,
will forthwith, upon the execution and delivery by the parties hereto of this
Twentieth Supplemental Indenture, cause the same to be recorded pursuant to law
in all offices for the recording of mortgages of real or personal property in
which such recordation is necessary in order to perfect and protect the lien
hereof, and, in any event, in all such offices in which it has caused or may
cause the Original Indenture to be recorded.

      Section 7.10.  Replacement on Loss, Etc.  Anything in the Series T bonds
or in the Indenture to the contrary notwithstanding, upon receipt by the Company
or the Trustee of evidence reasonably satisfactory to the Company or the Trustee
of the ownership of and loss, theft, destruction or mutilation of any Series T
bond and (a) in the case of loss, theft or destruction, of indemnity or security
reasonably satisfactory to it (provided, however, that if the holder of such
Series T bond is an institution having a minimum net worth of $10,000,000 or
more, its own affidavit and undertaking of indemnity shall be deemed to be
satisfactory evidence, indemnity and security) or (b) in the case of mutilation,
upon surrender and cancellation thereof, the Company at its expense will
execute, and thereupon the Trustee will authenticate and deliver in lieu
thereof, a new bond, executed and authenticated in the same manner as the bond
being replaced, in an aggregate principal amount equal to the unpaid portion of
the principal amount of the bond being replaced.

      Section 7.11.  Counterparts.  This Twentieth Supplemental Indenture may be
executed in any number of counterparts, each of which shall be deemed an
original; and such counterparts shall constitute but one and the same
instrument, which shall for all purposes be sufficiently evidenced by any such
original counterpart.

      Section 7.12.  Rights and Remedies on Default.  For any default by the
Company in the covenants, stipulations, promises and agreements herein contained
or contained in the bonds of Series T, the Trustee

                                       38
<PAGE>

and the bondholders, subject to the rights of the Insurer, shall have the same
rights and remedies, subject to the same limitations, as are provided in the
Original Indenture.

     IN WITNESS WHEREOF, The Providence Gas Company has caused its corporate
seal to be hereto affixed and these presents to be executed, acknowledged and
delivered in its name and on its behalf by its President and Treasurer, and said
State Street Bank and Trust Company, as successor as Trustee to Rhode Island
Hospital Trust National Bank, which succeeded Rhode Island Hospital Trust
Company, has caused its corporate seal to be hereto affixed and these presents
to be executed and delivered by one of its officers, all hereunto duly
authorized, as of the day and year first above written.

                                             THE PROVIDENCE GAS COMPANY

(CORPORATE SEAL)                             By_____________________________
                                                    James H. Dodge
                                                    Its President


                                             By_____________________________
                                                    Gary S. Gillheeney
                                                    Its Treasurer

Signed, sealed and delivered in the presence of:


_________________________________
as to The Providence Gas Company

     STATE STREET BANK AND TRUST COMPANY, Trustee


[CORPORATE SEAL]                             By_____________________________
                                                    Authorized Officer

Signed, sealed and delivered in the presence of:


_________________________________
as to State Street Bank and Trust Company

                                       39
<PAGE>

STATE OF RHODE ISLAND   )
                        ) : SS.:
COUNTY OF PROVIDENCE    )

     In Providence, this 1/st/ day of February A.D. 1999, personally appeared
before me James H. Dodge, to me known and known by me to be the President of THE
PROVIDENCE GAS COMPANY, one of the parties that executed the foregoing
instrument, and acknowledged said instrument to be his free act and deed in his
capacity, and the free act and deed of said corporation; and on oath stated that
he was duly authorized to execute said instrument and that the seal affixed
thereto 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
                              My Commission Expires: ___________________

                                         [Notarial Seal]



STATE OF RHODE ISLAND  )
                       ):SS.:
COUNTY OF PROVIDENCE   )

     In Providence, this 1/st/ day of February A.D. 1999, personally appeared
before me Gary S. Gillheeney, to me known and known by me to be the Treasurer of
THE PROVIDENCE GAS COMPANY, one of the parties that executed the foregoing
instrument, and acknowledged said instrument to be his free act and deed in his
said capacity; and the free act and deed of said corporation; and on oath stated
that he was duly authorized to execute said instrument and that the seal affixed
thereto 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
                              My Commission Expires: ___________________

                                         [Notarial Seal]

                                       40
<PAGE>

STATE OF RHODE ISLAND  )
                       ): SS.:
COUNTY OF PROVIDENCE   )

     In Providence, this 1st day of February A. D. 1999, personally appeared
before me, Christopher J. Lembo to me known and known by me to be Assistant Vice
President of STATE STREET BANK AND TRUST COMPANY, one of the parties that
executed the foregoing instrument, and acknowledged said instrument to be his
free act and deed in his said capacity, and the free act and deed of said
corporation; and on oath stated that he was duly authorized to execute said
instrument and that the seal affixed thereto 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
                              Print Name:  Eleanore F. Gaines
                              My Commission Expires: July 14, 2001

                                         [Notarial Seal]

                                       41
<PAGE>

                   SCHEDULE OF PROPERTY AND INTEREST THEREIN


                                     None






                                  SCHEDULE I
                     (to Twentieth Supplemental Indenture)

<PAGE>

                         SCHEDULE OF RELEASED PROPERTY



                                     None



                                  SCHEDULE II
                     (to Twentieth Supplemental Indenture)
<PAGE>

                        FORM OF REQUEST FOR REDEMPTION

                            PROVIDENCE GAS COMPANY
                     First Mortgage Bond, Series T, 6.50%
                (6.50% Senior Secured Insured Quarterly Notes)
                             due February 1, 2029
                              CUSIP No. 743753AC9

     The undersigned Participant does hereby certify, pursuant to Section 4.05
of the Twentieth Supplemental Indenture dated as of February 1, 1999 to the
Indenture dated as of January 1, 1922 between THE PROVIDENCE GAS COMPANY (the
"Company") and STATE STREET BANK AND TRUST COMPANY, as trustee (the "Trustee"),
to the Company and the Trustee that:

     1.   [Name of deceased Beneficial Owner] is deceased.

     2.   [Name of deceased Beneficial Owner] had an interest in $______ in face
principal amount of the Company's First Mortgage Bond, Series T, 6.50% (also
known as 6.50% Senior Secured Insured Quarterly Notes) due February 1, 2029 (the
"Notes").

     3.   [Name of Representative] is [Beneficial Owner's personal
representative/other person authorized to represent the estate of the Beneficial
Owner/surviving joint tenant/surviving tenant by the entirety] of [Name of
deceased Beneficial Owner] and has delivered to the undersigned a request for
redemption in form satisfactory to the undersigned, requesting that $__________
[$1,000 or an integral multiple thereof] be redeemed pursuant to said Section
4.05. Such request and the documents accompanying such request, all of which are
satisfactory to the undersigned, are delivered herewith.

     4.   [Name of Participant] holds the interest in the Notes with respect to
which this Request for Redemption is being made on behalf of [Name of deceased
Beneficial Owner].

     IN WITNESS WHEREOF, the undersigned has executed this Request for
Redemption as of __________, ____.

                              [Name of Participant]

                              By:__________________________

                              Name:________________________

                              Title:_______________________



                                 SCHEDULE III

<PAGE>

                     (to Twentieth Supplemental Indenture)