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                                                                     EXHIBIT 4a3

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                                  ARKLA, INC.

                                       TO

                            CITIBANK, N.A., Trustee

                               ---------------

                         SECOND SUPPLEMENTAL INDENTURE


                         Dated as of November 15, 1989

                               ---------------

                         SUPPLEMENTING AND AMENDING THE

                     INDENTURE DATED AS OF DECEMBER 1, 1986




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         SECOND SUPPLEMENTAL INDENTURE, dated as of November 15, 1989,
between ARKLA, INC., a corporation duly organized and existing under the laws
of the State of Delaware (herein called the "Company"), having its principal
office at 525 Milam Street, Shreveport, Louisiana 71101 and at 400 East Capitol
Street, Little Rock, Arkansas 72202, and CITIBANK, N.A., a national banking
association, as Trustee (herein called the "Trustee").

                                R E C I T A L S

         WHEREAS, to provide for its lawful corporate purposes the Company has
duly authorized the issue from time to time of its debentures, notes or other
evidences of unsecured indebtedness, which are to be issued in one or more
series (the "Securities"); the Company has heretofore made, executed and
delivered to the Trustee its Indenture dated as of December 1, 1986 and its
First Supplemental Indenture, dated as of September 30, 1988, (collectively,
the "Indenture"); and

         WHEREAS, the Board of Directors of the Company has determined that it
is desirable to add an additional covenant of the Company to Article Ten of the
Indenture solely for the benefit of the Holders of each series of Securities
which provides that such series will have the benefit of such covenant in which
the Company will covenant and agree that each Holder of the Securities shall
have the right, at such Holder's option, to require the Company to purchase all
or any part of such Holder's Securities, at the option of such Holder, on a
specified date if certain events occur and certain conditions specified in this
Supplemental Indenture are met; and

         WHEREAS, Section 901 of Article Nine of the Original Indenture
provides that under certain conditions the Company and Trustee, may, without
the consent of the Holders of Securities, from time to time and at any time,
enter into an indenture or indentures supplemental thereto, inter alia, (a) to
add to the covenants of the Company for the benefit of the Holders of all or
any series of Securities (and if such covenants are to be for the benefit of
less than all series of Securities, stating that such covenants are expressly
being included solely for the benefit of such series) or to surrender any right
or power herein conferred upon the Company; or (b) to add any additional Events
of Default; and

         WHEREAS, all the requirements prescribed by law and by the Certificate
of Incorporation of the Company have been fully complied with and all
conditions and requirements necessary to authorize the execution,
acknowledgment and delivery of this Second Supplemental Indenture and duly and
legally effect the modifications and alterations of the Indenture provided for
in this Second Supplemental Indenture, and to make the Indenture as
supplemented and amended by this Second Supplemental Indenture, a valid,
binding and legal instrument for the benefit of the Holders of Securities, have
been complied with;





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         NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH that for
and in consideration of the premises and the acceptances or purchases of the
Securities by the Holders thereof, the Company and the Trustee mutually
covenant and agree for the equal and proportionate benefit of all Holders of
the Securities or of series thereof, as follows:

                                   ARTICLE I

                         MODIFICATION OF THE INDENTURE

         SECTION 1.1  SUPPLEMENT TO ARTICLE TEN OF THE INDENTURE.  Article Ten
of the Indenture is modified by adding a new and additional Section to the
Indenture, which additional Section shall read in its entirety as follows:

         SECTION 1013.  Put Right of Holders Upon a Designated Event and a
         Rating Decline.

         If the terms of any series of Securities provides that such series
         shall have the benefit of the following covenant, the Company hereby
         agrees as follows:

                 In the event that there occurs at any time prior to any date
         specified in the terms of such series both (a) a Designated Event (as
         hereinafter defined) with respect to the Company and (b) a Rating
         Decline (as hereinafter defined), each Holder of the Securities shall
         have the right, at such Holder's option, to require the Company to
         purchase all or any part of such Holder's Securities on the date
         ("Repurchase Date") that is 100 days after the last to occur of public
         notice of the Designated Event and the Rating Decline, at 100% of the
         principal amount thereof, plus accrued interest to the Repurchase
         Date.

                 On or before the twenty-eighth day after the last to occur of
         public notice of the occurrence of a Designated Event and the Rating
         Decline, the Company is obligated to notify the Trustee of such
         events, and promptly thereafter to mail, or cause to be mailed,
         first-class, postage prepaid, to all Holders of the Securities, at the
         address of record of such Holder, a notice regarding the Designated
         Event, the Rating Decline and the repurchase right.  The notice shall
         state the Repurchase Date, the date by which the repurchase right must
         be exercised, the applicable price for such Securities and the
         procedure which the Holder must follow to exercise this right.  To
         exercise this right, the Holder of such Securities must deliver at
         least ten days prior to the Repurchase Date written notice to the
         Company (or an agent designated by the Company for such purpose and
         notified to the Trustee and the Holders)





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         of the Holder's exercise of such right, the name in which the
         Securities were registered, and the principal amount to be
         repurchased, together with the Securities with respect to which the
         right is being exercised, duly endorsed for transfer to the Company.
         Such written notice shall be irrevocable.  Securities repurchased
         pursuant to this section shall be delivered to the Trustee and
         cancelled as provided in Section 309 of the Indenture.

                 As used herein, a "Designated Event" shall be deemed to have
         occurred at such a time as (i) a "person" or "group" (within the
         meaning of Section 13 (d) (3) of the Securities Exchange Act of 1934,
         as amended (the 1934 Act")) becomes the "beneficial owner" (as defined
         in Rule 13d-3 under the 1934 Act) of more than 30% of the total voting
         power of all classes of stock then outstanding of the Company normally
         entitled to vote in elections of directors ("Voting Stock"); or (ii)
         during any period of two consecutive years, individuals who at the
         beginning of such period constituted the Company's Board of Directors
         (together with any new director whose election by the Company's Board
         of Directors or whose nomination for election by the Company's
         shareholders was approved by a vote of at least two-thirds of the
         directors then still in office who either were directors at the
         beginning of such period or whose election or nomination for election
         was previously so approved) cease for any reason to constitute a
         majority of the directors then in office; or (iii) the Company
         consolidates with or merges into another corporation or conveys,
         transfers or leases all or substantially all of its assets to any
         person, or any corporation consolidates with or merges into the
         Company, in either event pursuant to a transaction in which Voting
         Stock of the Company is changed into or exchanged for cash, securities
         or other property, provided that such transaction (a) between the
         Company and its Subsidiaries or between Subsidiaries or (b) involving
         the exchange of the Company's Voting Stock as consideration in the
         acquisition of another business or businesses (without change or
         exchange of the Company's outstanding Voting Stock into or for cash,
         securities or other property) shall be excluded from the operation of
         this clause (iii); or (iv) the Company, one or more employee benefit
         plans ("Employee Benefit Plans") as defined in Section 3(3) of the
         Employee Retirement Income Security Act of 1974, as amended,
         maintained by the Company or any Subsidiary thereof, or any Subsidiary
         purchases or otherwise acquires, directly or indirectly, beneficial
         ownership of Voting Stock of the Company if, after giving effect to
         such purchase or acquisition, the Company (together with such Employee
         Benefit Plans and such Subsidiaries) acquires 20% or more of the
         Company's Voting Stock within any 12-month period; or (v) on any date
         (a





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         "Calculation Date") the Company makes any distribution or
         distributions of cash, property or securities (other than regular
         dividends, and distributions of capital stock of the Company) to
         holders of Voting Stock of the Company or the Company, any Employee
         Benefit Plans or any Subsidiary purchases or otherwise acquires
         beneficial ownership of Voting Stock of the Company and the sum of the
         fair market value of such distribution or purchase, plus the fair
         market value of all other such distributions and purchases which have
         occurred during the preceding 12-month period, is at least 20% of the
         fair market value of the outstanding Voting Stock of the Company.  The
         percentage in clause (v) above is calculated on such Calculation Date
         by determining the percentage of the fair market value of the
         Company's outstanding Voting Stock as of such Calculation Date which
         is represented by the fair market value of the distributions and
         purchases which have occurred on such date and adding to that
         percentage all of the percentages which have been similarly calculated
         on the Calculation Dates of all such distributions and purchases
         during the preceding 12-month period.

                 As used herein, a "Rating Decline" shall be deemed to have
         occurred if on any date within the 90-day period following public
         notice of the occurrence of a Designated Event (which period shall be
         extended so long as the rating of the Securities is under publicly
         announced consideration for possible downgrade by a Rating Agency (as
         hereinafter defined) (i) in the event the Securities are rated by one
         or both Rating Agencies on the Rating Date (as hereinafter defined) as
         Investment Grade (as hereinafter defined), the rating of the
         Securities by such Rating Agency or Rating Agencies shall fall below
         Investment Grade, or (ii) in the event the Securities are rated by
         both Rating Agencies on the Rating Date below Investment Grade, the
         rating of the Securities by either Rating Agency shall be at least one
         Full Rating Category (as hereinafter defined) below the rating of the
         Securities by such Rating Agency on the Rating Date.

                 As used herein, "Rating Agency" shall mean Standard & Poor's
         Corporation and its successors ("S&P"), and Moody's Investors Service,
         Inc. and its successors ("Moody's"), or if S&P or Moody's or both
         shall not make a rating on the Securities publicly available, a
         nationally recognized statistical rating agency or agencies, as the
         case may be, selected by the Company which shall be substituted for
         S&P or Moody's or both, as the case may be; "Investment Grade" shall
         mean BBB- or higher by S&P or Baa3 or higher by Moody's or the
         equivalent of such ratings by S&P or Moody's or by any other Rating
         Agency selected as provided above, and "Rating Date" shall mean the
         date which





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         is 121 days prior to public notice of the occurrence of a Designated
         Event.

                 As used herein, the term "Full Rating Category" shall mean (i)
         with respect to S&P, any of the following categories: BB, B, CCC, CC
         and C, (ii) with respect to Moody's, any of the following categories:
         Ba, B, Caa, Ca and C and (iii) with respect to any other Rating
         Agency, the equivalent of any such category of S&P or Moody's used by
         such other Rating Agency.  In determining whether the rating of the
         Securities has decreased by the equivalent of one Full Rating
         Category, gradation within Full Rating Categories (+ and - for S&P; 1,
         2, and 3 for Moody's; or the equivalent gradation for another Rating
         Agency) shall be taken into account (e.g., with respect to S&P, a
         decline in a rating from BB+ to BB-, or from BB to B+, will constitute
         a decrease of less than one Full Rating Category).

                 Default in the performance or breach of this covenant with
         respect to Securities of any series entitled to the benefits of this
         covenant shall be an Event of Default with respect to all series of
         Securities entitled to the benefits of this covenant pursuant to
         Section 501(7) of the Indenture following the continuance of such
         default or breach for a period of 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, or to
         the Company and the Trustee by the Holders of not less than 25% in
         aggregate principal amount of all series of Securities entitled to the
         benefits of this covenant at the time Outstanding.

                 The Company may omit in any particular instance to comply with
         any term, provision or condition set forth in this covenant, with
         respect to the Securities of any series entitled to the benefits of
         this covenant if before the time for such compliance the Holders of at
         least 66 2/3% in aggregate principal amount of the Outstanding
         Securities of such series shall, by Act of such Holders, either waive
         such compliance in such instance or generally waive compliance with
         such term, provision or condition, but no such waiver shall extend to
         or affect such term, provision or condition except to the extent so
         expressly waived, and, until such waiver shall become effective, the
         obligations of the Company and the duties of the Trustee in respect of
         any such term, provision or condition shall remain in full force and
         effect.





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                                   ARTICLE II

                    PARTICULAR REPRESENTATIONS AND COVENANTS
                                 OF THE COMPANY

         SECTION 2.1  AUTHORITY OF THE ISSUER.  The Company is duly authorized
under the laws of the State of Delaware and all other applicable laws to
execute and deliver this Second Supplemental Indenture, and all corporate
action on its part required for the execution and delivery of this Second
Supplemental Indenture has been, duly and effectively taken.

         SECTION 2.2  TRUTH OF RECITALS AND STATEMENTS.  The Company warrants
that the recitals of fact and statements contained in this Second Supplemental
Indenture are true and correct, and that the recitals of fact and statements
contained in all certificates and other documents furnished thereunder will be
true and correct.

                                  ARTICLE III

                             CONCERNING THE TRUSTEE

         SECTION 3.1  ACCEPTANCE OF TRUSTS.  The Trustee accepts the trusts
hereunder and agrees to perform the same, but only upon the terms and
conditions set forth in the Indenture and in this Second Supplemental
Indenture, to all of which the Issuer and the respective Holders of Securities
at any time outstanding agree by their acceptance thereof.

         SECTION 3.2  NO RESPONSIBILITY OF TRUSTEE FOR RECITALS, ETC.  The
recitals and statements contained in this Second Supplemental Indenture shall
be taken as the recitals and statements of the Company, and the Trustee assumes
no responsibility for the correctness of the same.  The Trustee makes no
representations as to the validity or sufficiency of this second Supplemental
Indenture.

                                   ARTICLE IV

                            MISCELLANEOUS PROVISIONS

         SECTION 4.1  RELATION TO THE INDENTURE.  The provisions of this second
Supplemental Indenture shall become effective immediately upon the execution
and delivery hereof.  This Second Supplemental Indenture is executed as and
shall constitute an indenture supplemental to the Indenture.  All the terms and
provisions herein contained shall form a part of the indenture for all purposes
as fully and with the same effect as if all such terms and provisions had been
set forth in the Indenture and each and every term and condition contained in
the Indenture shall apply to this Second Supplemental Indenture with the same
force and effect as if the same were in this





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Second Supplemental Indenture set forth in full, with such omissions,
variations and modifications thereof as may be appropriate to make each such
term and condition conform to this Second Supplemental Indenture.  The
Indenture is hereby ratified and confirmed and shall remain and continue in
full force and effect in accordance with the terms and provisions thereof, as
supplemented and amended by this Second Supplemental Indenture and the
Indenture and this Second Supplemental Indenture shall be read, taken and
construed together as one instrument.  This Second Supplemental Indenture shall
be governed by and construed in accordance with the laws of the State of New
York.

         SECTION 4.2  TRUST INDENTURE ACT.  If any provision of this Second
Supplemental Indenture limits, qualifies or conflicts with any other provision
of this Second Supplemental Indenture or any provision of the Indenture which
is required to be included by any of the provisions of Sections 310 to 317
inclusive of the Trust Indenture Act of 1939, such required provision shall
control.

         SECTION 4.3  MEANING OF TERMS.  Any term used in this Second
Supplemental Indenture which is defined in the Indenture shall have the meaning
specified in the Indenture, unless the context shall otherwise require.

         SECTION 4.4  COUNTERPARTS.  This Second Supplemental Indenture may be
executed in several counterparts, each of which shall be deemed to be an
original, but all of which together shall constitute one instrument.

         IN WITNESS WHEREOF, the parties have caused this Second Supplemental
Indenture to be duly executed, and their respective corporate seals to be
hereunto affixed and attested, all as of the day and year first above written.

Attest:                             ARKLA, INC.

/s/ B. D. KLINE                     /s/ JIM WILHITE
--------------------------          ------------------------------------
B. D. Kline                         Name:  Jim Wilhite
Vice President-Finance,             Title: Vice Chairman of the Board
Secretary and Treasurer


Attest:                             CITIBANK, N.A., as Trustee

PAM C. REBUCCI                      /s/ P. DEFELICE
--------------------------          ------------------------------------
Name:  Pam C. Rebucci               Name:  P. DeFelice
Title: Trust Officer                Title: Vice President

(CORPORATE SEAL)





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STATE OF LOUISIANA

PARISH OF CADDO

         On this 21 day of November, 1989 before me personally came Jim
Wilhite, to me known, who, being by me duly sworn, did depose and say that he
is Vice Chairman of ARKLA, INC., one of the corporations described in and which
executed the foregoing instrument; that he knows the corporate seal of said
corporation; that the seal affixed to said instrument is such corporate seal;
that it was so affixed by authority of the Board of Directors of said
corporation, and that he signed his name thereto by like authority.

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


(NOTARIAL SEAL)                         LOIS S. ALEXANDER
                                        ---------------------------------
                                        Notary Public
                                        Commission Expires: 
                                                           --------------




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STATE OF NEW YORK

COUNTY OF NEW YORK

         On this 22 day of November, 1989 before me personally came P.
DeFelice, to me known, who, being by me duly sworn, did depose and say that he
is Vice President of CITIBANK, N.A., one of the corporations described in and
which executed the foregoing instrument; that he knows the corporate seal of
said corporation; that the seal affixed to said instrument is such corporate
seal; that it was so affixed by authority of the Board of Directors of said
corporation, and that he signed his name thereto by like authority.

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


(NOTARIAL SEAL)                         ENZO L. CARBOCCI
                                        ---------------------------------
                                        Notary Public
                                        Commission Expires: 
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                                                   ENZO . CARBOCCI
                                        Notary Public, State of New York
                                                   No. 43-5605595
                                            Qualified in Richmond County
                                        Certificate Filed in New York County
                                            Term Expires March 30, 1990



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