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                                                                 EXHIBIT 4(a)(7)

                                                                [CONFORMED COPY]
 
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                                  TENNECO INC.
 
                                      AND
 
                            THE CHASE MANHATTAN BANK
                            (NATIONAL ASSOCIATION),
 
                                                                      AS TRUSTEE
 
                              ------------------
 
                          NINTH SUPPLEMENTAL INDENTURE
 
                         DATED AS OF NOVEMBER 15, 1992
 
                                       TO
 
                                   INDENTURE
 
                           DATED AS OF MARCH 15, 1988
 
                              ------------------
 
                         PROVIDING FOR THE ISSUANCE OF
                               8% NOTES DUE 1999
 
 
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  Ninth Supplemental Indenture dated as of November 15, 1992, between Tenneco
Inc., a corporation duly organized and existing under the laws of the State of
Delaware (hereinafter called the "Company"), and The Chase Manhattan Bank
(National Association), a national banking association existing under the laws
of the United States of America, as trustee (hereinafter called the
"Trustee").
 
  Whereas, the Company has heretofore executed and delivered to the Trustee an
indenture dated as of March 15, 1988 (hereinafter called the "Original
Indenture"), to provide for the issue of an unlimited amount of debentures,
notes and/or other debt obligations of the Company (hereinafter referred to as
the "Securities"), the terms of which are to be determined as set forth in
(S) 2.02 of the Original Indenture; and
 
  Whereas, (S) 12.01 of the Original Indenture provides, among other things,
that the Company and the Trustee may enter into indentures supplemental to the
Original Indenture for, among other things, the purpose of setting forth the
terms of Securities of any series; and
 
  Whereas, the Company desires to create a series of the Securities in an
aggregate principal amount of $250,000,000 to be designated the "8% Notes due
1999" (the "Notes"), and all action on the part of the Company necessary to
authorize the issuance of the Notes under the Original Indenture and this
Ninth Supplemental Indenture has been duly taken; and
 
  Whereas, all acts and things necessary to make the Notes, when executed by
the Company and authenticated and delivered by the Trustee as in the Indenture
provided, the valid and binding obligations of the Company, and to constitute
these presents a valid and binding supplemental indenture and agreement
according to its terms, have been done and performed;
 
  Now, therefore, in consideration of the premises and of the mutual covenants
herein contained, and of the acceptance of this trust by the Trustee, and of
the sum of one dollar to the Company duly paid by the Trustee at the execution
and delivery of these presents, and of other valuable consideration the
receipt whereof is hereby acknowledged and in order to authorize the
authentication and delivery of and to set forth the terms of the Notes,
 
  It is hereby covenanted, declared and agreed by and between the parties
hereto, for the benefit of holders of the Notes issued under the Indenture, as
follows:
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                                  ARTICLE 1.
 
                    Terms and Issuance of 8% Notes Due 1999
 
  (S) 1.01. Issue of Notes. A series of Securities which shall be designated
the "8% Notes due 1999" shall be executed, authenticated and delivered in
accordance with the provisions of, and shall in all respects be subject to,
the terms, conditions and covenants of the Indenture, including without
limitation the terms set forth in this Ninth Supplemental Indenture (including
the form of Notes set forth in (S) 1.02 hereof). The aggregate principal
amount of Notes which may be authenticated and delivered under the Indenture
shall not, except as permitted by the provisions of (S)(S) 2.07, 2.08, 2.10,
2.11 or 3.02 of the Indenture, exceed $250,000,000. The entire amount of Notes
may forthwith be executed by the Company and delivered to the Trustee and
shall be authenticated by the Trustee and delivered to or upon the order of
the Company pursuant to (S) 2.03 of the Indenture.
 
  (S) 1.02. Forms of Notes and Authentication Certificate. The forms of the
Notes and the Trustee's certificate of authentication shall be substantially
as follows:
 
                            [form of face of note]
 
                                 TENNECO INC.
 
                               8% NOTE DUE 1999
 
No.                                                                           $
 
  Tenneco Inc., a corporation organized and existing under the laws of the
State of Delaware (hereinafter called the "Company," which term shall include
any successor corporation as defined in the Indenture hereinafter referred
to), for value received, hereby promises to pay to       or registered
assigns, the sum of       Dollars on November 15, 1999, in any coin or
currency of the United States of America which at the time of payment is legal
tender for the payment of public and private debts, and to pay to the
registered holder hereof as hereinafter provided interest thereon at the rate
per annum specified in the title hereof in like coin or currency, from the May
15 or November 15 next preceding the date hereof to which interest has been
paid, unless the date hereof is a May 15 or November 15 to which interest on
the Notes has been paid, in which case from the date hereof, or unless no
interest has been paid on the Notes since the original issue date (hereinafter
referred to) of this Note, in which case from the original issue date, semi-
annually on May 15 and November 15 in each year, until payment of said
 
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principal sum has been made or duly provided for, and to pay interest on any
overdue principal and (to the extent permitted by law) on any overdue
installment of interest at the rate of 8% per annum. Notwithstanding the
foregoing, when there is no existing default in the payment of interest on the
Notes, if the date hereof is after April 30 or October 31 and prior to the
following May 15 or November 15, as the case may be, this Note shall bear
interest from May 15 or November 15; provided, however, that if the Company
shall default in the payment of interest due on such May 15 or November 15,
then this Note shall bear interest from the May 15 or November 15 to which
interest has been paid or, if no interest has been paid on the Notes since the
original issue date of this Note, from the original issue date. The interest
so payable on any May 15 or November 15 will, subject to certain exceptions
provided in the Indenture hereinafter referred to, be paid to the person in
whose name this Note is registered at the close of business on the April 30 or
October 31, as the case may be, next preceding such May 15 or November 15, or
if such April 30 or October 31 is not a business day, the business day next
preceding such April 30 or October 31. Interest on this Note shall be computed
on the basis of a 360-day year of twelve 30-day months. Both principal of and
interest on this Note are payable at the principal office of the Trustee in
the Borough of Manhattan, The City of New York, New York; provided, however,
that payment of interest may be made, at the option of the Company, by check
mailed to the address of the person entitled thereto as such address shall
appear on the Note register. The original issue date in respect of the Notes
is November 24, 1992.
 
  ADDITIONAL PROVISIONS OF THIS NOTE ARE CONTAINED ON THE REVERSE HEREOF AND
SUCH PROVISIONS SHALL FOR ALL PURPOSES HAVE THE SAME EFFECT AS THOUGH FULLY
SET FORTH AT THIS PLACE.
 
  This Note shall not be entitled to any benefit under the Indenture
hereinafter referred to, or become valid or obligatory for any purpose, until
the Trustee under the Indenture shall have signed the form of certificate of
authentication endorsed hereon.
 
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  In Witness Whereof, Tenneco Inc. has caused this Instrument to be signed in
its name by its Chairman of the Board or its President or a Vice President,
and its corporate seal (or facsimile thereof) to be hereto affixed and
attested by its Secretary or an Assistant Secretary.
 
Dated..............................
 
                                   Tenneco Inc.
 
                                   By..........................................
                                                          Chairman of the Board
 
Attest:
 
 ...................................
                          Secretary
 
                           [form of reverse of note]
 
                                 TENNECO INC.
 
                               8% NOTE DUE 1999
 
  This Note is one of a duly authorized issue of Notes of the Company known as
its 8% Notes due 1999 (herein called the "Notes"), limited to the aggregate
principal amount of $250,000,000, all issued under and equally entitled to the
benefits of an Indenture (herein, together with any amendments and supplements
thereto, including without limitation the form and terms of Securities issued
pursuant thereto, called the "Indenture"), dated as of March 15, 1988,
executed by the Company to The Chase Manhattan Bank (National Association)
(herein, together with any successor thereto, called the "Trustee"), as
Trustee, to which Indenture reference is hereby made for a statement of the
rights thereunder of the Trustee and of the registered holders of the Notes
and of the duties thereunder of the Trustee and the Company.
 
  The Notes are not subject to redemption prior to maturity.
 
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  The Indenture permits the Company to issue unsecured debentures, notes
and/or other evidences of indebtedness in one or more series ("Securities") up
to such principal amount or amounts as may be authorized in accordance with
the terms of the Indenture.
 
  To the extent permitted by, and as provided in, the Indenture, modifications
or alterations of the Indenture and of the rights and obligations of the
Company and of the holders of the Notes may be made with the consent of the
Company and with the consent of the holders of not less than a majority in
principal amount of the Securities of all series then outstanding under the
Indenture (treated as a single class) which are affected by the modification
or amendment thereto; provided, however, that without the consent of the
holder hereof no such modification or alteration shall be made which will
affect the terms of payment of the principal of or interest on this Note.
 
  In case a default, as defined in the Indenture, shall occur, the principal
of all the Notes at any such time outstanding under the Indenture may be
declared or may become due and payable, upon the conditions and in the manner
and with the effect provided in the Indenture. The Indenture provides that
such declaration may in certain events be waived by the holders of a majority
in principal amount of the Notes outstanding in the case of payment defaults
on the Notes and in certain other events by the holders of a majority in
principal amount of the Securities of all series then outstanding under the
Indenture (treated as a single class) which are affected thereby.
 
  The Indenture provides that no holder of any Note may enforce any remedy
under the Indenture except in the case of refusal or neglect of the Trustee to
act after notice of default and after request by the holders of a majority in
principal amount of the outstanding Notes in certain events (and in certain
other events by the holders of a majority in principal amount of the
Securities of all series then outstanding under the Indenture, treated as a
single class, which are affected thereby) and the offer to the Trustee of
security and indemnity satisfactory to it; provided, however, that such
provision shall not prevent the holder hereof from enforcing payment of the
principal of or interest on this Note.
 
  The transfer of this Note is registrable by the registered holder hereof, in
person or by duly authorized attorney, at the agency of the Company in the
Borough of Manhattan, The City of New York, New York, on books of the Company
to be kept for that purpose at said agency, upon surrender and cancellation of
this Note and on presentation of a duly executed written instrument of
transfer, and thereupon a new Note or Notes, of the same aggregate principal
amount and in authorized denominations, will be issued to
 
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the transferee or transferees in exchange herefor; and this Note, with or
without other Notes, may in like manner be exchanged for one or more new Notes
of other authorized denominations but of the same aggregate principal amount;
all subject to the terms and conditions set forth in the Indenture.
 
  The Company, the Trustee, any paying agent and any Registrar of the Notes
may deem and treat the person in whose name this Note is registered as the
absolute owner hereof for all purposes whatsoever, and neither the Company nor
the Trustee nor any paying agent nor any Registrar of the Notes shall be
affected by any notice to the contrary.
 
  No recourse shall be had for the payment of the principal of, or the
interest on, this Note, or for any claim based hereon or on the Indenture,
against any incorporator, or against any stockholder, director or officer, as
such, past, present or future, of the Company, or of any predecessor or
successor corporation, either directly or through the Company or any such
predecessor or successor corporation, whether by virtue of any constitution,
statute or rule of law, or by the enforcement of any assessment or penalty or
otherwise, all such liability, whether at common law, in equity, by any
constitution, statute or otherwise, of incorporators, stockholders, directors
or officers being released by every owner hereof by the acceptance of this
Note and as part of the consideration for the issue hereof, and being likewise
released by the terms of the Indenture; provided, however, that nothing herein
or in the Indenture contained shall be taken to prevent recourse to and the
enforcement of the liability, if any, of any stockholder or subscriber to
capital stock of the Company upon or in respect of shares of capital stock not
fully paid up.
 
  All terms used in this Note which are defined in the Indenture shall have
the meanings assigned to them in the Indenture.
 
               [form of trustee's certificate of authentication]
 
  This Note is one of the 8% Notes due 1999 described in the within-mentioned
Indenture.
 
                                   THE CHASE MANHATTAN BANK
                                     (National Association),
 
                                                                       Trustee,
 
                                        By ....................................
                                                   Authorized Officer.
 
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                                      7
 
                                  ARTICLE 2.
 
                                 Miscellaneous
 
  (S) 2.01. Execution as Supplemental Indenture. This Ninth Supplemental
Indenture is executed and shall be construed as an indenture supplemental to
the Original Indenture and, as provided in the Original Indenture, this Ninth
Supplemental Indenture forms a part thereof. Except as herein expressly
otherwise defined, the use of the terms and expressions herein is in
accordance with the definitions, uses and constructions contained in the
Original Indenture.
 
  (S) 2.02. Responsibility for Recitals, Etc. The recitals herein and in the
Notes (except in the Trustee's certificate of authentication) shall be taken
as the statements of the Company, and the Trustee assumes no responsibility
for the correctness thereof. The Trustee makes no representations as to the
validity or sufficiency of this Ninth Supplemental Indenture or of the Notes.
The Trustee shall not be accountable for the use or application by the Company
of the Notes or of the proceeds thereof.
 
  (S) 2.03. Provisions Binding on Company's Successors. All the covenants,
stipulations, promises and agreements in this Ninth Supplemental Indenture
contained by the Company shall bind its successors and assigns whether so
expressed or not.
 
  (S) 2.04. New York Contract. This Ninth Supplemental Indenture and each Note
shall be deemed to be a contract made under the laws of the State of New York,
and for all purposes shall be construed in accordance with the laws of said
State without regard to principles of conflicts of laws.
 
  (S) 2.05. Execution and Counterparts. This Ninth Supplemental Indenture may
be executed in any number of counterparts, each of which shall be an original
but such counterparts shall together constitute but one and the same
instrument.
 
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                                      8
 
  In Witness Whereof, said Tenneco Inc. has caused this Ninth Supplemental
Indenture to be executed in its corporate name by its Chairman of the Board or
its President or one of its Vice Presidents, and said The Chase Manhattan Bank
(National Association) has caused this Ninth Supplemental Indenture to be
executed in its corporate name by one of its Vice Presidents as of November
15, 1992.
 
                                   Tenneco Inc.
 
                                                 Robert T. Blakely
                                   By .........................................
                                                 Robert T. Blakely
                                               Senior Vice President
 
                                   The Chase Manhattan Bank
                                     (National Association)
 
                                                 C. J. Heinzelmann
                                   By .........................................
                                               Charles J. Heinzelmann
                                                   Vice President