Exhibit 4f   
          =================================================================




                                  INDENTURE OF TRUST
                                   (1997 SERIES C)


                                       BETWEEN



                         THE INDUSTRIAL DEVELOPMENT AUTHORITY
                                OF THE COUNTY OF PIMA



                                         AND



                    FIRST TRUST OF NEW YORK, NATIONAL ASSOCIATION




                                       --------




                            DATED AS OF SEPTEMBER 15, 1997



                                       --------




                                     Authorizing

                        Industrial Development Revenue Bonds,
                                    1997 Series C
                       (Tucson Electric Power Company Project)


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


          

                                  TABLE OF CONTENTS*

                                                                       Page
                                                                       ----

             Parties  . . . . . . . . . . . . . . . . . . . . . . . . .   1
             Recitals . . . . . . . . . . . . . . . . . . . . . . . . .   1
             Granting Clause  . . . . . . . . . . . . . . . . . . . . .   2

                                      ARTICLE I

                                     DEFINITIONS

             Section 1.01.  Definitions . . . . . . . . . . . . . . . . . 2

                                      ARTICLE II

                                      THE BONDS

             Section 2.01.  Creation of Bonds . . . . . . . . . . . . . . 8
             Section 2.02.  Form of Bonds . . . . . . . . . . . . . . . . 8
             Section 2.03.  Execution of Bonds  . . . . . . . . . . . . . 9
             Section 2.04.  Authentication of Bonds . . . . . . . . . . . 9
             Section 2.05.  Bonds Not General Obligations . . . . . . . . 9
             Section 2.06.  Prerequisites to Authentication of Bonds  . . 9
             Section 2.07.  Lost or Destroyed Bonds or Bonds Canceled in
                            Error . . . . . . . . . . . . . . . . . . .  10
             Section 2.08.  Transfer, Registration and Exchange of 
                            Bonds . . . . . . . . . . . . . . . . . . .  10
             Section 2.09.  Other Obligations . . . . . . . . . . . . .  12
             Section 2.10.  Temporary Bonds . . . . . . . . . . . . . .  12
             Section 2.11.  Cancellation of Bonds . . . . . . . . . . .  12
             Section 2.12.  Payment of Principal and Interest . . . . .  13
             Section 2.13.  Applicability of Book-Entry Provisions  . .  13


                                     ARTICLE III

                                 REDEMPTION OF BONDS

             Section 3.01.  Redemption Provisions . . . . . . . . . . .  13
             Section 3.02.  Selection of Bonds to be Redeemed . . . . .  14
             Section 3.03.  Procedure for Redemption  . . . . . . . . .  15
             Section 3.04.  Payment of Redemption Price . . . . . . . .  15
             Section 3.05.  No Partial Redemption After Default . . . .  15



          ____________________

          *  This table of contents is not a part of the Indenture, and is
             for convenience only.  The captions herein are of no legal
             effect and do not vary the meaning or legal effect of any part
             of the Indenture.


          


                                      ARTICLE IV

                                    THE BOND FUND

             Section 4.01.  Creation of Bond Fund . . . . . . . . . . .  16
             Section 4.02.  Liens . . . . . . . . . . . . . . . . . . .  16
             Section 4.03.  Deposits into Bond Fund . . . . . . . . . .  16
             Section 4.04.  Use of Moneys in Bond Fund  . . . . . . . .  16
             Section 4.05.  Custody of Bond Fund; Withdrawal of Moneys   16
             Section 4.06.  Bonds Not Presented for Payment . . . . . .  16
             Section 4.07.  Moneys Held in Trust  . . . . . . . . . . .  17

                                      ARTICLE V

                               DISPOSITION OF PROCEEDS

             Section 5.01.  Disposition of Proceeds . . . . . . . . . .  17

                                      ARTICLE VI

                                     INVESTMENTS

             Section 6.01.  Investments . . . . . . . . . . . . . . . .  17

                                     ARTICLE VII

                                  GENERAL COVENANTS

             Section 7.01.  No General Obligations  . . . . . . . . . .  18
             Section 7.02.  Performance of Covenants of the Authority;
                            Representations . . . . . . . . . . . . . .  18
             Section 7.03.  Maintenance of Rights and Powers; Compliance
                            with Laws . . . . . . . . . . . . . . . . .  18
             Section 7.04.  Enforcement of Obligations of the Company;
                            Amendments  . . . . . . . . . . . . . . . .  19
             Section 7.05.  Further Instruments . . . . . . . . . . . .  19
             Section 7.06.  No Disposition of Trust Estate  . . . . . .  19
             Section 7.07.  Financing Statements  . . . . . . . . . . .  19
             Section 7.08.  Tax Covenants; Rebate Fund  . . . . . . . .  19
             Section 7.09.  Notices of Trustee  . . . . . . . . . . . .  20

                                     ARTICLE VIII

                                      DEFEASANCE

             Section 8.01.  Defeasance  . . . . . . . . . . . . . . . .  20

                                      ARTICLE IX

                                DEFAULTS AND REMEDIES

             Section 9.01.  Events of Default . . . . . . . . . . . . .  22
             Section 9.02.  Remedies  . . . . . . . . . . . . . . . . .  23
             Section 9.03.  Restoration to Former Position  . . . . . .  23
             Section 9.04.  Owners' Right to Direct Proceedings . . . .  23
             Section 9.05.  Limitation on Owners' Right to Institute
                            Proceedings . . . . . . . . . . . . . . . .  23
             Section 9.06.  No Impairment of Right to Enforce Payment .  24
             Section 9.07.  Proceedings by Trustee without Possession of
                            Bonds . . . . . . . . . . . . . . . . . . .  24
             Section 9.08.  No Remedy Exclusive . . . . . . . . . . . .  24
             Section 9.09.  No Waiver of Remedies . . . . . . . . . . .  24
             Section 9.10.  Application of Moneys . . . . . . . . . . .  24
             Section 9.11.  Severability of Remedies  . . . . . . . . .  25

                                      ARTICLE X

                TRUSTEE; PAYING AGENT AND CO-PAYING AGENTS; REGISTRAR

             Section 10.01. Acceptance of Trusts  . . . . . . . . . . .  25
             Section 10.02. No Responsibility for Recitals  . . . . . .  25
             Section 10.03. Limitations on Liability  . . . . . . . . .  26
             Section 10.04. Compensation, Expenses and Advances . . . .  26
             Section 10.05. Notice of Events of Default . . . . . . . .  27
             Section 10.06. Action by Trustee . . . . . . . . . . . . .  27
             Section 10.07. Good Faith Reliance . . . . . . . . . . . .  27
             Section 10.08. Dealings in Bonds and with the Authority and
                            the Company . . . . . . . . . . . . . . . .  27
             Section 10.09. Allowance of Interest . . . . . . . . . . .  28
             Section 10.10. Construction of Indenture . . . . . . . . .  28
             Section 10.11. Resignation of Trustee  . . . . . . . . . .  28
             Section 10.12. Removal of Trustee  . . . . . . . . . . . .  28
             Section 10.13. Appointment of Successor Trustee  . . . . .  28
             Section 10.14. Qualifications of Successor Trustee . . . .  29
             Section 10.15. Judicial Appointment of Successor Trustee .  29
             Section 10.16. Acceptance of Trusts by Successor Trustee .  29
             Section 10.17. Successor by Merger or Consolidation  . . .  29
             Section 10.18. Standard of Care  . . . . . . . . . . . . .  30
             Section 10.19. Notice to Owners of Bonds of Event of
                            Default . . . . . . . . . . . . . . . . . .  30
             Section 10.20. Intervention in Litigation of the Authority  30
             Section 10.21. Paying Agent; Co-Paying Agents  . . . . . .  30
             Section 10.22. Qualifications of Paying Agent and Co-Paying
                            Agents; Resignation; Removal  . . . . . . .  31
             Section 10.23. Registrar . . . . . . . . . . . . . . . . .  31
             Section 10.24. Qualifications of Registrar; Resignation;
                            Removal . . . . . . . . . . . . . . . . . .  32
             Section 10.25. Several Capacities  . . . . . . . . . . . .  32

                                      ARTICLE XI

                   EXECUTION OF INSTRUMENTS BY OWNERS OF BONDS AND
                             PROOF OF OWNERSHIP OF BONDS

             Section 11.01. Execution of Instruments; 
                            Proof of Ownership  . . . . . . . . . . . .  32

                                     ARTICLE XII

                MODIFICATION OF THIS INDENTURE AND THE LOAN AGREEMENT

             Section 12.01. Limitations . . . . . . . . . . . . . . . .  33
             Section 12.02. Supplemental Indentures without Owner
                            Consent . . . . . . . . . . . . . . . . . .  33
             Section 12.03. Supplemental Indentures with Consent of
                            Owners  . . . . . . . . . . . . . . . . . .  34
             Section 12.04. Effect of Supplemental Indenture  . . . . .  35
             Section 12.05. Consent of the Company  . . . . . . . . . .  35
             Section 12.06. Amendment of Loan Agreement without Consent
                            of Owners . . . . . . . . . . . . . . . . .  35
             Section 12.07. Amendment of Loan Agreement with Consent of
                            Owners  . . . . . . . . . . . . . . . . . .  35

                                     ARTICLE XIII

                                    MISCELLANEOUS

             Section 13.01. Successors of the Authority . . . . . . . .  36
             Section 13.02. Parties in Interest . . . . . . . . . . . .  36
             Section 13.03. Severability  . . . . . . . . . . . . . . .  36
             Section 13.04. No Personal Liability of Authority 
                            Officials . . . . . . . . . . . . . . . . .  36
             Section 13.05. Bonds Owned by the Authority or the Company  36
             Section 13.06. Counterparts  . . . . . . . . . . . . . . .  37
             Section 13.07. Governing Law . . . . . . . . . . . . . . .  37
             Section 13.08. Notices . . . . . . . . . . . . . . . . . .  37
             Section 13.09. Holidays  . . . . . . . . . . . . . . . . .  37
             Section 13.10. Statutory Notice Regarding Cancellation of
                            Contracts . . . . . . . . . . . . . . . . .  38


          Testimonium . . . . . . . . . . . . . . . . . . . . . . . .    40
          Signatures and Seals  . . . . . . . . . . . . . . . . . . .    40

          Exhibit A - Form of Bond  . . . . . . . . . . . . . . . . . . A-1
          Exhibit B - Form of Endorsement of Transfer . . . . . . . . . B-1
          Exhibit C - Form of Certificate of Authentication . . . . . . C-1


          


                                  INDENTURE OF TRUST

               THIS INDENTURE OF TRUST (1997 C Series), dated as of
          September 15, 1997 (this "Indenture"), between THE INDUSTRIAL
          DEVELOPMENT AUTHORITY OF THE COUNTY OF PIMA, an Arizona nonprofit
          corporation designated by law as a political subdivision of the
          State of Arizona (hereinafter called the "Authority"), and First
          Trust of New York, National Association, as trustee (hereinafter
          called the "Trustee"),

                                W I T N E S S E T H :


               WHEREAS, the Authority is authorized and empowered under
          Title 35, Chapter 5, Arizona Revised Statutes, as amended (the
          "Act"), to issue its bonds in accordance with the Act and to make
          secured or unsecured loans for the purpose of financing or
          refinancing the acquisition, construction, improvement or
          equipping of projects consisting of land, any building or other
          improvement, and all real and personal properties, including but
          not limited to machinery and equipment, whether or not now in
          existence or under construction, whether located within or
          without Pima County, which shall be suitable for, among other
          things, facilities for the furnishing of electric energy, gas or
          water, air and water pollution control facilities and sewage and
          solid waste disposal facilities, and to charge and collect
          interest on such loans and pledge the proceeds of loan agreements
          as security for the payment of the principal of and interest on
          bonds, or designated issues of bonds, issued by the Authority and
          any agreements made in connection therewith, whenever the Board
          of Directors of the Authority finds such loans to be in
          furtherance of the purposes of the Authority or in the public
          interest;

               WHEREAS, the Authority has heretofore issued and sold
          $75,000,000 aggregate principal amount of its Industrial
          Development Revenue Bonds, 1983 Series A (Tucson Electric Power
          Company General Project) all of which remain outstanding (the
          "1983 Bonds), the proceeds of which were loaned to Tucson
          Electric Power Company, an Arizona corporation (the "Company") to
          finance a portion of the costs of the acquisition, construction,
          improvement and equipping of certain of its facilities for the
          furnishing of electric energy (the "Facilities"); and

               WHEREAS, the Authority proposes to issue and sell its
          revenue bonds as provided herein (the "Bonds") to refinance, by
          the payment or redemption of the 1983 Bonds, or provision
          therefor, the portion of the costs of the acquisition,
          construction, improvement and equipping of the Facilities paid
          from the proceeds of the 1983 Bonds, all as described in Exhibit
          A to the Loan Agreement, dated as of September 15, 1997 (the
          "Loan Agreement"), between the Authority and the Company;

               NOW, THEREFORE, for and in consideration of these premises
          and the mutual covenants herein contained, of the acceptance by
          the Trustee of the trusts hereby created, of the purchase and
          acceptance of the Bonds by the Owners (as hereinafter defined)
          thereof and of the sum of one dollar lawful money of the United
          States of America, to it duly paid by the Trustee at or before
          the execution and delivery of these presents, and for other good
          and valuable consideration the receipt and sufficiency of which
          are hereby acknowledged, in order to secure the payment of the
          principal of and premium, if any, and interest on the Bonds at
          any time Outstanding (as hereinafter defined) under this
          Indenture according to their tenor and effect and the performance
          and observance by the Authority of all the covenants and
          conditions expressed or implied herein and contained in the
          Bonds, the Authority does hereby grant, bargain, sell, convey,
          mortgage, pledge and assign, and grant a security interest in,
          the Trust Estate (as hereinafter defined) to the Trustee, its
          successors in trust and their assigns forever;

               TO HAVE AND TO HOLD all the same with all privileges and
          appurtenances hereby conveyed and assigned, or agreed or intended
          so to be, to the Trustee, its successors in trust and their
          assigns forever;

               IN TRUST NEVERTHELESS, upon the terms and trusts herein set
          forth, first, for the equal and proportionate benefit and
          security of all Owners of the Bonds issued under and secured by
          this Indenture without preference, priority or distinction as to
          the lien of any Bonds over any other Bonds;

               PROVIDED, HOWEVER, that if, after the right, title and
          interest of the Trustee in and to the Trust Estate shall have
          ceased, terminated and become void in accordance with Article
          VIII hereof, the principal of and premium, if any, and interest
          on the Bonds shall have been paid to the Owners thereof, or shall
          have been paid to the Company pursuant to Section 4.06 hereof,
          then and in that case these presents and the estate and rights
          hereby granted shall cease, terminate and be void, and thereupon
          the Trustee shall cancel and discharge this Indenture and execute
          and deliver to the Authority and the Company such instruments in
          writing as shall be requisite to evidence the discharge hereof;
          otherwise this Indenture is to be and remain in full force and
          effect.

               THIS INDENTURE OF TRUST FURTHER WITNESSETH, and it is
          expressly declared, that all Bonds issued and secured hereunder
          are to be issued, authenticated and delivered, and the Trust
          Estate and the other estate and rights hereby granted are to be
          dealt with and disposed of, under, upon and subject to the terms,
          conditions, stipulations, covenants, agreements, trusts, uses and
          purposes as hereinafter expressed, and the Authority has agreed
          and covenanted, and does hereby agree and covenant, with the
          Trustee and with the respective Owners, from time to time, of the
          Bonds, as follows:


                                      ARTICLE I

                                     DEFINITIONS

               Section 1.01.  Definitions.  The terms defined in this
          Article I shall, for all purposes of this Indenture, have the
          meanings herein specified, unless the context clearly requires
          otherwise:

          Act:

               "Act" shall mean Title 35, Chapter 5, Arizona Revised
          Statutes, and all acts supplemental thereto or amendatory
          thereof.

          Administration Expenses:

               "Administration Expenses" shall mean the reasonable expenses
          incurred by the Authority with respect to the Loan Agreement,
          this Indenture and any transaction or event contemplated by the
          Loan Agreement or this Indenture, including the compensation and
          reimbursement of expenses and advances payable to the Trustee, to
          the Paying Agent, any Co-Paying Agent and the Registrar and a pro
          rata share of the Authority's annual operating expenses in
          accordance with the provisions of paragraph XII.D. of the
          Authority's Procedural Pamphlet.

          Authority:

               "Authority" shall mean The Industrial Development Authority
          of the County of Pima, an Arizona nonprofit corporation
          designated by law as a political subdivision of the State of
          Arizona incorporated for and with the approval of Pima County,
          Arizona, pursuant to the provisions of the Constitution of the
          State of Arizona and the Act, its successors and their assigns.

          Authorized Company Representative:

               "Authorized Company Representative" shall mean each person
          at the time designated to act on behalf of the Company by written
          certificate furnished to the Authority and the Trustee containing
          the specimen signature of such person and signed on behalf of the
          Company by its President, any Vice President or its Treasurer,
          together with its Secretary or any Assistant Secretary.

          Bond Counsel:

               "Bond Counsel" shall mean any firm or firms of nationally
          recognized bond counsel experienced in matters pertaining to the
          validity of, and exclusion from gross income for federal tax
          purposes of interest on bonds issued by states and political
          subdivisions, selected by the Company and acceptable to the
          Authority.

          Bond Fund:

          "Bond Fund" shall mean the fund created by Section 4.01 hereof.

          Bonds:

               "Bond" or "Bonds" shall mean the bonds authorized to be
          issued under this Indenture.

          Code:

               "Code" shall mean the Internal Revenue Code of 1986 or any
          successor statute thereto.  Each reference to a section of the
          Code herein shall be deemed to include the United States Treasury
          Regulations proposed or in effect thereunder and applicable to
          the Bonds or the use of proceeds thereof, unless the context
          clearly requires otherwise.  References to any particular Code
          section shall, in the event of a successor Code, be deemed to be
          a reference to the successor to such Code section.

          Company:

               "Company" shall mean Tucson Electric Power Company, a
          corporation organized and existing under the laws of the State of
          Arizona, its successors and their assigns, including, without
          limitation, any successor obligor under Section 6.01 or 7.01 of
          the Loan Agreement to the extent of the obligations assumed
          thereunder.

          Depositary:

               "Depositary" shall mean The Depository Trust Company or any
          successor thereto as a securities repository for the Bonds.

          Facilities:

               "Facilities" shall mean the real and personal properties,
          machinery and equipment currently existing, under construction
          and to be constructed which are described in Exhibit A to the
          Loan Agreement, as revised from time to time to reflect any
          changes therein, additions thereto, substitutions therefor and
          deletions therefrom permitted by the terms of the Loan Agreement,
          subject, however, to the provisions of Section 7.01 of the Loan
          Agreement.

          Government Obligations:

               "Government Obligations" shall mean:

                    (a) direct obligations of, or obligations the principal
               of and interest on which are unconditionally guaranteed by,
               the United States of America entitled to the benefit of the
               full faith and credit thereof; and

                    (b) certificates, depositary receipts or other
               instruments which evidence a direct ownership interest in
               obligations described in clause (a) above or in any specific
               interest or principal payments due in respect thereof;
               provided, however, that the custodian of such obligations or
               specific interest or principal payments shall be a bank or
               trust company organized under the laws of the United States
               of America or of any state or territory thereof or of the
               District of Columbia, with a combined capital stock surplus
               and undivided profits of at least $50,000,000; and provided,
               further, that except as may be otherwise required by law,
               such custodian shall be obligated to pay to the holders of
               such certificates, depositary receipts or other instruments
               the full amount received by such custodian in respect of
               such obligations or specific payments and shall not be
               permitted to make any deduction therefrom.

          Indenture:

               "Indenture" shall mean this Indenture of Trust, dated as of
          September 15, 1997, between the Authority and the Trustee, and
          any and all modifications, alterations, amendments and
          supplements thereto.

          Investment Securities:

               "Investment Securities" shall mean any of the following
          obligations or securities on which neither the Company nor any of
          its subsidiaries is the obligor: (a) Government Obligations; (b)
          interest bearing deposit accounts (which may be represented by
          certificates of deposit) in national, state or foreign banks
          having a combined capital and surplus of not less than
          $10,000,000; (c) bankers' acceptances drawn on and accepted by
          commercial banks having a combined capital and surplus of not
          less than $10,000,000; (d) (i) direct obligations of, (ii)
          obligations the principal of and interest on which are
          unconditionally guaranteed by, and (iii) any other obligations
          the interest on which is exempt from federal income taxation
          issued by, any state of the United States of America, the
          District of Columbia or the Commonwealth of Puerto Rico, or any
          political subdivision, agency, authority or other instrumentality
          of any of the foregoing, which, in any case, are rated by a
          nationally recognized rating agency in any of its three highest
          rating categories; (e) obligations of any agency or
          instrumentality of the United States of America; (f) commercial
          or finance company paper which is rated by a nationally
          recognized rating agency in any of its three highest rating
          categories; (g) corporate debt securities issued by corporations
          having debt securities rated by a nationally recognized rating
          agency in any of its three highest rating categories; (h)
          repurchase agreements with banking or financial institutions
          having a combined capital and surplus of not less than
          $10,000,000 with respect to any of the foregoing obligations or
          securities; (i) shares or interests in registered investment
          companies whose assets consist of obligations or securities which
          are described in any other clause of this sentence; and (j) any
          other obligations which may lawfully be purchased by the Trustee. 
          The commercial banks and banking institutions referred to above
          may include the entities acting as Trustee, Paying Agent,
          Co-Paying Agent or Registrar hereunder if such entities shall
          otherwise satisfy the requirements set forth above.

          Loan Agreement:

               "Loan Agreement" shall mean the Loan Agreement, dated as of
          September 15, 1997, between the Authority and the Company
          relating to the Bonds, and any and all modifications,
          alterations, amendments and supplements thereto.

          Loan Payments:

               "Loan Payments" shall mean the payments required to be made
          by the Company pursuant to Section 5.01 of the Loan Agreement.

          1954 Code:

               "1954 Code" shall mean the Internal Revenue Code of 1954, as
          amended.

          1983 Bonds:

               "1983 Bonds" shall mean the $75,000,000 aggregate principal
          amount of the Authority's Industrial Development Revenue Bonds,
          1983 Series A (Tucson Electric Power Company General Project).

          Notice by Mail:

               "Notice by Mail" or "notice" of any action or condition "by
          Mail" shall mean a written notice meeting the requirements of
          this Indenture mailed by first-class mail to the Owners of
          specified registered Bonds at the addresses shown in the
          registration books maintained pursuant to Section 2.08 hereof;
          provided, however, that if, because of the temporary or permanent
          suspension of delivery of first-class mail or for any other
          reason, it is impossible or impracticable to give such notice by
          first-class mail, then such giving of notice in lieu thereof,
          which may include publication, as shall be made with the approval
          of the Trustee (or, if there be no trustee hereunder, the
          Authority) shall constitute a sufficient giving of such notice.

          Notice by Publication:

               "Notice by Publication" or "notice" of any action or
          condition "by Publication" shall mean publication of a notice
          meeting the requirements of this Indenture in a newspaper or
          financial journal of general circulation in The City of New York,
          New York, which carries financial news, is printed in the English
          language and is customarily published on each business day;
          provided, however, that any successive weekly publication of
          notice required hereunder may be made, unless otherwise expressly
          provided herein, on the same or different days of the week and in
          the same or different newspapers or financial journals; and
          provided, further, that if, because of the temporary or permanent
          suspension of the publication or general circulation of any
          newspaper or financial journal or for any other reason, it is
          impossible or impracticable to publish such notice in the manner
          herein described, then such publication in lieu thereof as shall
          be made with the approval of the Trustee (or, if there be no
          trustee hereunder, the Authority) shall constitute a sufficient
          publication of such notice.

          Outstanding:

               "Outstanding", when used in reference to the Bonds, shall
          mean, as at any particular date, the aggregate of all Bonds
          authenticated and delivered under this Indenture except:

                    (a) those canceled by the Trustee at or prior to such
               date or delivered to or acquired by the Trustee at or prior
               to such date for cancellation;

                    (b) those deemed to be paid in accordance with Article
               VIII hereof; and

                    (c) those in lieu of or in exchange or substitution for
               which other Bonds shall have been authenticated and
               delivered pursuant to this Indenture, unless proof
               satisfactory to the Trustee and the Company is presented
               that such Bonds are held by a bona fide holder in due
               course.

          Owner:

               "Owner" shall mean the person in whose name any Bond is
          registered upon the registration books maintained pursuant to
          Section 2.08 hereof.  The Company may be an Owner.

          Paying Agent; Co-Paying Agent; Principal Office thereof:

               "Paying Agent" and "Co-Paying Agent" shall mean the paying
          agent and any co-paying agent appointed in accordance with
          Section 10.21 hereof.  "Principal Office" of the Paying Agent or
          any Co-Paying Agent shall mean the office thereof designated in
          writing to the Trustee.

          Rebate Fund:

               "Rebate Fund" shall mean the fund created by Section 7.08
          hereof.

          Receipts and Revenues of the Authority from the Loan Agreement:

               "Receipts and Revenues of the Authority from the Loan
          Agreement" shall mean all moneys paid or payable to the Trustee
          for the account of the Authority by the Company in respect of the
          Loan Payments and payments pursuant to Section 9.01 of the Loan
          Agreement and all receipts of the Trustee which, under the
          provisions of this Indenture, reduce the amount of such payments.

          Record Date:

               "Record Date" shall mean the close of business on the
          fifteenth (15th) day of the calendar month immediately preceding
          each regularly scheduled interest payment date.

          Registrar; Principal Office thereof:

               "Registrar" shall mean the registrar appointed in accordance
          with Section 10.23 hereof.  "Principal Office" of the Registrar
          shall mean the office thereof designated in writing to the
          Trustee.

          Supplemental Indenture:

               "Supplemental Indenture" shall mean any indenture of the
          Authority modifying, altering, amending, supplementing or
          confirming this Indenture for any purpose, in accordance with the
          terms hereof.

          Supplemental Loan Agreement:

               "Supplemental Loan Agreement" shall mean any agreement
          between the Authority and the Company modifying, altering,
          amending or supplementing the Loan Agreement, in accordance with
          the terms thereof and hereof.

          Tax Agreement:

               "Tax Agreement" shall mean that tax certificate and
          agreement, dated the date of the initial authentication and
          delivery of the Bonds, between the Authority and the Company,
          relating to the requirements of the Code and the 1954 Code, and
          any and all modifications, alterations, amendments and
          supplements thereto.

          Trust Estate:

               "Trust Estate" shall mean at any particular time all right,
          title and interest of the Authority in and to the Loan Agreement
          (except its rights under Sections 5.03, 5.04, 6.03 and 8.05
          thereof and any rights of the Authority to receive notices,
          certificates, requests, requisitions and other communications
          thereunder), including without limitation, the Receipts and
          Revenues of the Authority from the Loan Agreement, the Bond Fund
          and all moneys and Investment Securities from time to time on
          deposit therein (excluding, however, any moneys or Investment
          Securities held in the Rebate Fund), any and all other moneys and
          obligations (other than Bonds) which at such time are deposited
          or are required to be deposited with, or are held or are required
          to be held by or on behalf of, the Trustee, the Paying Agent or
          any Co-Paying Agent in trust under any of the provisions of this
          Indenture and all other rights, titles and interests which at
          such time are subject to the lien of this Indenture; provided,
          however, that in no event shall there be included in the Trust
          Estate (a) moneys or obligations deposited with or held by the
          Trustee in the Rebate Fund pursuant to Section 7.08 hereof or (b)
          moneys or obligations deposited with or paid to the Trustee for
          the redemption or payment of Bonds which are deemed to have been
          paid in accordance with Article VIII hereof or moneys held
          pursuant to Section 4.06 hereof.

          Trustee; Principal Office thereof:

               "Trustee" shall mean First Trust of New York, National
          Association, as trustee under this Indenture, its successors in
          trust and their assigns.  "Principal Office" of the Trustee shall
          mean the principal corporate trust office of the Trustee, which
          office at the date of acceptance by the Trustee of the duties and
          obligations imposed on the Trustee by this Indenture is located
          at the address specified in Section 13.08 hereof.


                                      ARTICLE II

                                      THE BONDS

               Section 2.01.  Creation of Bonds.  There is hereby
          authorized and created under this Indenture, for the purpose of
          providing moneys to pay, or redeem, or provide for the redemption
          therefor, of the 1983 Bonds, an issue of Bonds, entitled to the
          benefit, protection and security of this Indenture, in the
          aggregate principal amount of Seventy-Five Million Dollars
          ($75,000,000).  Each of the Bonds shall be designated by the
          title "The Industrial Development Authority of the County of Pima
          Industrial Development Revenue Bond, 1997 Series C (Tucson
          Electric Power Company Project)".  The Bonds shall mature,
          subject to prior redemption upon the terms and conditions
          hereinafter set forth, on September 1, 2029 and shall bear
          interest from the date thereof until payment of the principal or
          redemption price thereof shall have been made or provided for in
          accordance with the provisions hereof, whether at maturity, upon
          redemption or otherwise, at the rate of six per centum (6%) per
          annum, with interest thereon payable semi-annually on each March
          1 and September 1, commencing March 1, 1998.  Interest shall be
          calculated on the basis of a 360-day year consisting of twelve
          30-day months.

               Section 2.02.  Form of Bonds.  Bonds shall be authenticated
          and delivered hereunder solely as fully registered bonds without
          coupons in the denomination of $5,000 or integral multiples
          thereof.  Bonds shall be numbered as determined by the Trustee. 
          Bonds authenticated prior to the first interest payment date
          shall be dated September 15, 1997.  Bonds authenticated on or
          subsequent to the first interest payment date shall be dated the
          interest payment date next preceding the date of authentication
          thereof, unless such date of authentication shall be an interest
          payment date to which interest on the Bonds has been paid in full
          or duly provided for, in which case they shall be dated such date
          of authentication; provided, however, that if, as shown by the
          records of the Trustee, interest on the Bonds shall be in
          default, Bonds issued in exchange for Bonds surrendered for
          transfer or exchange shall be dated the date to which interest
          has been paid in full on the Bonds surrendered.

               Principal of and premium, if any, on Bonds shall be payable
          to the Owners of such Bonds upon presentation and surrender of
          such Bonds at the Principal Office of the Paying Agent or any
          Co-Paying Agent.  Interest on the Bonds shall be paid by check
          drawn upon the Paying Agent and mailed to the Owners of such
          Bonds as of the close of business on the Record Date with respect
          to each interest payment date at the registered addresses of such
          Owners as they shall appear as of the close of business on such
          Record Date on the registration books maintained pursuant to
          Section 2.08 hereof notwithstanding the cancellation of any such
          Bond upon any exchange or registration of transfer subsequent to
          such Record Date, except that if and to the extent that there
          should be a default on the payment of interest on any Bond, such
          defaulted interest shall be paid to the Owners in whose name such
          Bond (or any Bond or Bonds issued upon any exchange or
          registration of transfer thereof) is registered as of the close
          of business on a date selected by the Trustee in its discretion,
          but not more than 15 days or less than 10 days prior to the date
          of payment of such defaulted interest; notwithstanding the
          foregoing, upon request to the Paying Agent by an Owner of not
          less than $1,000,000 in aggregate principal amount of Bonds,
          interest on such Bonds and, after presentation and surrender of
          such Bonds, the principal thereof shall be paid to such Owner by
          wire transfer to the account maintained within the continental
          United States specified by such Owner or, if such Owner maintains
          an account with the entity acting as Paying Agent, by deposit
          into such account.  Payment as aforesaid shall be made in such
          coin or currency of the United States of America as, at the
          respective times of payment, shall be legal tender for the
          payment of public and private debts.

               The Bonds and the form for registration of transfer and the
          form of certificate of authentication to be printed on the Bonds
          are to be in substantially the forms thereof set forth in
          Exhibits A, B and C hereto, respectively, with necessary or
          appropriate variations, omissions and insertions as permitted or
          required by this Indenture.

               Section 2.03.  Execution of Bonds.  The Bonds shall be
          executed on behalf of the Authority by the President or a Vice
          President of the Authority and shall have affixed, impressed or
          reproduced thereon the official seal of the Authority which shall
          be attested by the Secretary or an Assistant Secretary of the
          Authority.  Each of the foregoing officers may execute or cause
          to be executed with a facsimile signature in lieu of his manual
          signature the Bonds, provided the signature of either the
          President or a Vice President of the Authority or the Secretary
          or Assistant Secretary of the Authority shall, if required by
          applicable laws, be manually subscribed.

               In case any officer of the Authority whose signature or a
          facsimile of whose signature shall appear on the Bonds shall
          cease to be such officer before the authentication by the Trustee
          and delivery of such Bonds, such signature or such facsimile
          shall nevertheless be valid and sufficient for all purposes, the
          same as if such officer had remained in office until delivery;
          and any Bond may be signed on behalf of the Authority by such
          persons as, at the time of execution of such Bond, shall be the
          proper officers of the Authority, even though at the date of such
          Bond or of the execution and delivery of this Indenture any such
          person was not such officer.

               Section 2.04.  Authentication of Bonds.  Only such Bonds as
          shall have endorsed thereon a certificate of authentication
          substantially in the form set forth in Exhibit C hereto duly
          executed by the Trustee shall be entitled to any right or benefit
          under this Indenture.  No Bond shall be valid or obligatory for
          any purpose unless and until such certificate of authentication
          shall have been duly executed by the Trustee, and such executed
          certificate of authentication of the Trustee upon any such Bonds
          shall be conclusive evidence that such Bond has been
          authenticated and delivered under this Indenture.  The Trustee's
          certificate of authentication on any Bond shall be deemed to have
          been executed by it if signed with an authorized signature of the
          Trustee, but it shall not be necessary that the same person sign
          the certificate of authentication on all of the Bonds issued
          hereunder.  This Section 2.04 is subject to the provisions of
          Section 10.17 hereof.

               Section 2.05.  Bonds Not General Obligations.  Neither Pima
          County, Arizona nor the State of Arizona shall in any event be
          liable for the payment of the principal of or premium, if any, or
          interest on the Bonds, and neither the Bonds nor the premium, if
          any, or the interest thereon, shall be construed to constitute an
          indebtedness of Pima County, Arizona or the State of Arizona
          within the meaning of any constitutional or statutory provisions
          whatsoever.  The Bonds and the premium, if any, and the interest
          thereon shall be limited obligations of the Authority payable
          solely from the Receipts and Revenues of the Authority from the
          Loan Agreement and the other moneys pledged therefor under this
          Indenture, and such fact shall be plainly stated on the face of
          each Bond.

               Section 2.06.  Prerequisites to Authentication of Bonds. 
          The Authority shall execute and deliver to the Trustee and the
          Trustee shall authenticate the Bonds and deliver said Bonds to
          the initial purchasers thereof as may be directed hereinafter in
          this Section 2.06.

               Prior to the delivery on original issuance by the Trustee of
          any authenticated Bonds there shall be or have been delivered to
          the Trustee:

                    (a) a duly certified copy of a resolution of the Board
               of Directors of the Authority authorizing the execution and
               delivery of this Indenture and the Loan Agreement and the
               issuance of the Bonds;

                    (b) an original duly executed counterpart or a duly
               certified copy of the Loan Agreement;

                    (c) a request and authorization to the Trustee on
               behalf of the Authority, signed by its President or a Vice
               President, to authenticate and deliver the Bonds in the
               aggregate principal amount determined by this Indenture to
               the purchaser or purchasers therein identified upon payment
               to the Trustee, but for the account of the Authority, of a
               sum specified in such request and authorization plus any
               accrued interest on such Bonds to the date of delivery; and

                    (d) a written statement on behalf of the Company,
               executed by the President, any Vice President or the
               Treasurer, (i) approving the issuance and delivery of the
               Bonds and (ii) consenting to each and every provision of
               this Indenture.

               Section 2.07.  Lost or Destroyed Bonds or Bonds Canceled in
          Error.  If any Bond, whether in temporary or definitive form, is
          lost (whether by reason of theft or otherwise), destroyed
          (whether by mutilation, damage, in whole or in part, or
          otherwise) or canceled in error, the Authority may execute and
          the Trustee may authenticate a new Bond of like date and
          denomination and bearing a number not contemporaneously
          outstanding; provided that (a) in the case of any mutilated Bond,
          such mutilated Bond shall first be surrendered to the Trustee and
          (b) in the case of any lost Bond or Bond destroyed in whole,
          there shall be first furnished to the Authority, the Trustee and
          the Company evidence of such loss or destruction.  In every case,
          the applicant for a substitute Bond shall furnish the Authority,
          the Trustee and the Company such security or indemnity as may be
          required by any of them.  In the event any lost or destroyed Bond
          or a Bond canceled in error shall have matured or is about to
          mature, or has been called for redemption, instead of issuing a
          substitute Bond the Trustee may, in its discretion, pay the same
          without surrender thereof if there shall be first furnished to
          the Authority, the Trustee and the Company evidence of such loss,
          destruction or cancellation, together with indemnity,
          satisfactory to them.  Upon the issuance of any substitute Bond,
          the Authority and the Trustee may require the payment of a sum
          sufficient to cover any tax or other governmental charge that may
          be imposed in relation thereto.  The Trustee may charge the Owner
          of any such Bond with the Trustee's reasonable fees and expenses
          in connection with any transaction described in this Section
          2.07.

               Every substitute Bond issued pursuant to the provisions of
          this Section 2.07 by virtue of the fact that any Bond is lost,
          destroyed or canceled in error shall constitute an additional
          contractual obligation of the Authority, whether or not the Bond
          so lost, destroyed or canceled shall be at any time enforceable,
          and shall be entitled to all the benefits of this Indenture
          equally and proportionately with any and all other Bonds duly
          issued hereunder.  All Bonds shall be held and owned upon the
          express condition that, to the extent permitted by law, the
          foregoing provisions are exclusive with respect to the
          replacement or payment of lost, destroyed or improperly canceled
          Bonds, notwithstanding any law or statute now existing or
          hereafter enacted.

               Section 2.08.  Transfer, Registration and Exchange of Bonds. 
          The Registrar shall maintain and keep, at its Principal Office,
          books for the registration and registration of transfer of Bonds,
          which, at all reasonable times, shall be open for inspection by
          the Authority, the Trustee and the Company; and, upon
          presentation for such purpose of any Bond entitled to
          registration or registration of transfer at the Principal Office
          of the Registrar, the Registrar shall register or register the
          transfer in such books, under such reasonable regulations as the
          Registrar may prescribe.  The Registrar shall make all necessary
          provisions to permit the exchange or registration of transfer of
          Bonds at its Principal Office.

               The transfer of any Bond shall be registered upon the
          registration books of the Registrar at the written request of the
          Owner thereof or his attorney duly authorized in writing, upon
          surrender thereof at the Principal Office of the Registrar,
          together with a written instrument of transfer satisfactory to
          the Registrar duly executed by the Owner or his duly authorized
          attorney.  Upon the registration of transfer of any such Bond or
          Bonds, the Authority shall issue in the name of the transferee,
          in authorized denominations, a new Bond or Bonds in the same
          aggregate principal amount as the surrendered Bond or Bonds.

               The Authority, the Trustee, the Paying Agent, any Co-Paying
          Agent and the Registrar may deem and treat the Owner of any Bond
          as the absolute owner of such Bond, whether such Bond shall be
          overdue or not, for the purpose of receiving payment of, or on
          account of, the principal of and premium, if any, and, except as
          provided in Section 2.02 hereof, interest on, such Bond and for
          all other purposes, and neither the Authority, the Trustee, the
          Paying Agent, any Co-Paying Agent nor the Registrar shall be
          affected by any notice to the contrary.  All such payments so
          made to any such Owner or upon his order shall be valid and
          effective to satisfy and discharge the liability upon such Bond
          to the extent of the sum or sums so paid.

               Bonds, upon surrender thereof at the Principal Office of the
          Registrar may, at the option of the Owner thereof, be exchanged
          for an equal aggregate principal amount of Bonds of any
          authorized denomination.

               In all cases in which the privilege of exchanging Bonds or
          registering the transfer of Bonds is exercised, the Authority
          shall execute and the Trustee shall authenticate and deliver
          Bonds in accordance with the provisions of this Indenture.  For
          every such exchange or registration of transfer of Bonds, whether
          temporary or definitive, the Authority, the Registrar, or the
          Trustee may make a charge sufficient to reimburse it for any tax
          or other governmental charge required to be paid with respect to
          such exchange or registration of transfer, which sum or sums
          shall be paid by the person requesting such exchange or
          registration of transfer as a condition precedent to the exercise
          of the privilege of making such exchange or registration of
          transfer.  The Registrar shall not be obligated (a) to make any
          such exchange or registration of transfer of Bonds during the
          fifteen (15) days next preceding the date on which notice of any
          proposed redemption of Bonds is given or (b) to make any exchange
          or registration of transfer of any Bonds called for redemption.

               The Bonds are to be initially registered in the name of Cede
          & Co., as nominee for the Depositary.  Such Bonds shall not be
          transferable or exchangeable, nor shall any purported transfer be
          registered, except as follows:

                    (a) such Bonds may be transferred in whole, and
               appropriate registration of transfer effected, if such
               transfer is by such nominee to the Depositary, or by the
               Depositary to another nominee thereof, or by any nominee of
               the Depositary to any other nominee thereof, or by the
               Depositary or any nominee thereof to any successor
               securities depositary or any nominee thereof; and

                    (b) such Bond may be exchanged for definitive Bonds
               registered in the respective names of the beneficial holders
               thereof, and thereafter shall be transferable without
               restriction, if:

                    (i)  the Depositary shall have notified the Company and
               the Trustee that it is unwilling or unable to continue to
               act as securities depositary with respect to such Bonds and
               the Trustee shall not have been notified by the Company
               within ninety (90) days of the identity of a successor
               securities depositary with respect to such Bonds;

                    (ii)  the Company shall have delivered to the Trustee a
               written instrument to the effect that such Bonds shall be so
               exchangeable on and after a date specified therein; or

                    (iii)  (1) an Event of Default shall have occurred and
               be continuing, (2) the Trustee shall have given notice of
               such Event of Default pursuant to Section 10.19 hereof and
               (3) there shall have been delivered to the Authority, the
               Company and the Trustee an opinion of counsel to the effect
               that the interests of the beneficial owners of such Bonds in
               respect thereof will be materially impaired unless such
               owners become owners of definitive Bonds.

               The Bonds delivered to the Depositary may contain a legend
          reflecting the foregoing restrictions on registration of transfer
          and exchange.

               Section 2.09.  Other Obligations.  The Authority expressly
          reserves the right to issue, to the extent permitted by law, but
          shall not be obligated to issue, obligations under another
          indenture or indentures to provide additional funds to pay the
          cost of construction of the Facilities or to refund all or any
          principal amount of the Bonds, or any combination thereof.

               Section 2.10  Temporary Bonds.  Pending the preparation of
          definitive Bonds, the Authority may execute and the Trustee shall
          authenticate and deliver temporary Bonds.  Temporary Bonds shall
          be issuable as registered Bonds without coupons, of any
          authorized denomination, and substantially in the form of the
          definitive Bonds but with such omissions, insertions and
          variations as may be appropriate for temporary Bonds, all as may
          be determined by the Authority.  Temporary Bonds may contain such
          reference to any provisions of this Indenture as may be
          appropriate.  Every temporary Bond shall be executed by the
          Authority and be authenticated by the Trustee upon the same
          conditions and in substantially the same manner, and with like
          effect, as the definitive Bonds.  As promptly as practicable the
          Authority shall execute and shall furnish definitive Bonds and
          thereupon temporary Bonds may be surrendered in exchange therefor
          without charge at the Principal Office of the Trustee, and the
          Trustee shall authenticate and deliver in exchange for such
          temporary Bonds a like aggregate principal amount of definitive
          Bonds of authorized denominations.  Until so exchanged the
          temporary Bonds shall be entitled to the same benefits under this
          Indenture as definitive Bonds.

               Section 2.11.  Cancellation of Bonds.  All Bonds which shall
          have been surrendered to the Paying Agent or any Co-Paying Agent
          for payment or redemption, and all Bonds which shall have been
          surrendered to the Registrar for exchange or registration of
          transfer, shall be delivered to the Trustee for cancellation. 
          All Bonds delivered to or acquired by the Trustee for
          cancellation shall be canceled and destroyed by the Trustee.  The
          Trustee shall furnish to the Authority, the Paying Agent, the
          Registrar and the Company counterparts of certificates evidencing
          such cancellation and destruction and specifying such Bonds by
          number.

               Section 2.12.  Payment of Principal and Interest.  For the
          payment of interest on the Bonds, the Authority shall cause to be
          deposited in the Bond Fund, on each interest payment date, solely
          out of the Receipts and Revenues of the Authority from the Loan
          Agreement and other moneys pledged therefor, an amount sufficient
          to pay the interest to become due on such interest payment date. 
          The obligation of the Authority to cause any such deposit to be
          made hereunder shall be reduced by the amount of moneys in the
          Bond Fund available on such interest payment date for the payment
          of interest on the Bonds.

               For the payment of the principal of the Bonds upon maturity,
          the Authority shall cause to be deposited in the Bond Fund, on
          the stated or accelerated date of maturity, solely out of the
          Receipts and Revenues of the Authority from the Loan Agreement
          and other moneys pledged therefor, an amount sufficient to pay
          the principal of the Bonds.  The obligation of the Authority to
          cause any such deposit to be made hereunder shall be reduced by
          the amount of moneys in the Bond Fund available on the maturity
          date for the payment of the principal of the Bonds.

               Section 2.13.  Applicability of Book-Entry Provisions. 
          Anything in this Indenture to the contrary notwithstanding, (a)
          the provisions of the Blanket Issuer Letter of Representations,
          dated February 26, 1996, between the Authority and The Depository
          Trust Company relating to the manner of and procedures for
          payment and redemption of Bonds and related matters shall apply
          so long as such Depositary shall be the Owner of all Outstanding
          Bonds and (b) the Authority, the Trustee or the Paying Agent, as
          applicable, may enter into a similar agreement, on terms
          satisfactory to the Company, with any subsequent Depositary and
          the provisions thereof shall apply so long as such Depositary
          shall be the Owner of all Outstanding Bonds.


                                     ARTICLE III

                                 REDEMPTION OF BONDS

               Section 3.01.  Redemption Provisions.  (a)  The Bonds shall
          be subject to redemption by the Authority, at the direction of
          the Company, on any date on or after September 1, 2002 in whole
          at any time or in part from time to time, at the applicable
          redemption price (expressed as a percentage of principal amount)
          set forth below, plus accrued interest to the redemption date:

                  Redemption Period                 Redemption Price
                  -----------------                 ----------------

          September 1, 2002 through August 31, 2003        102%
          September 1, 2003 through August 31, 2004        101%
          September 1, 2004 and thereafter                 100%

               (b) The Bonds shall be subject to redemption by the
          Authority, at the direction of the Company, in whole at any time
          at the principal amount thereof plus accrued interest to the
          redemption date, if:

                    (i)  the Company shall have determined that the
               continued operation of the Facilities is impracticable,
               uneconomical or undesirable for any reason;

                    (ii)  all or substantially all of the Facilities shall
               have been condemned or taken by eminent domain; or

                    (iii)  the operation of the Facilities shall have been
               enjoined or shall have otherwise been prohibited by, or
               shall conflict with, any order, decree, rule or regulation
               of any court or of any federal, state or local regulatory
               body, administrative agency or other governmental body.

               (c)  The Bonds shall be subject to mandatory redemption by
          the Authority, at the principal amount thereof plus accrued
          interest to the redemption date, on the 180th day (or such
          earlier date as may be designated by the Company) after a final
          determination by a court of competent jurisdiction or an
          administrative agency, to the effect that, as a result of a
          failure by the Company to perform or observe any covenant,
          agreement or representation contained in the Loan Agreement, the
          interest payable on the Bonds is included for federal income tax
          purposes in the gross income of the owners thereof, other than
          any owner of a Bond who is a "substantial user" of the Facilities
          or a "related person" within the meaning of Section 103(b)(13) of
          the 1954 Code.  No determination by any court or administrative
          agency shall be considered final for the purposes of this Section
          3.01 (c) unless the Company shall have been given timely notice
          of the proceeding which resulted in such determination and an
          opportunity to participate in such proceeding, either directly or
          through an owner of a Bond, and until the conclusion of any
          appellate review sought by any party to such proceeding or the
          expiration of the time for seeking such review. The Bonds shall
          be redeemed either in whole or in part in such principal amount
          that, in the opinion of Bond Counsel, the interest payable on the
          Bonds, including the Bonds remaining outstanding after such
          redemption, would not be included in the gross income of any
          owner thereof, other than an owner of a Bond who is a
          "substantial user" of the Facilities or a "related person" within
          the meaning of Section 103(b)(13) of the 1954 Code.

               Section 3.02.  Selection of Bonds to be Redeemed.  If less
          than all the Bonds shall be called for redemption under any
          provision of this Indenture permitting such partial redemption,
          the particular Bonds or portions of Bonds to be redeemed shall be
          selected by the Trustee, in such manner as the Trustee in its
          discretion may deem proper, in the aggregate principal amount
          designated to the Trustee by the Company or otherwise as required
          by this Indenture; provided, however, that if, as indicated in a
          certificate of an Authorized Company Representative delivered to
          the Trustee, the Company shall have offered to purchase all Bonds
          then Outstanding and less than all such Bonds have been tendered
          to the Company for such purchase, the Trustee, at the direction
          of an Authorized Company Representative, shall select for
          redemption all such Bonds which shall not have been so tendered;
          and provided, further, that the portion of any Bond to be
          redeemed shall be in the principal amount of $5,000 or some
          integral multiple thereof and that, in selecting Bonds for
          redemption, the Trustee shall treat each Bond as representing
          that number of Bonds which is obtained by dividing the principal
          amount of such Bond by $5,000.  If it is determined that one or
          more, but not all, of the $5,000 units of principal amount
          represented by any such Bond is to be called for redemption,
          then, upon notice of intention to redeem such $5,000 unit or
          units, the Owner of such Bond shall forthwith surrender such Bond
          to the Paying Agent or any Co-Paying Agent for (y) payment to
          such Owner of the redemption price (including the redemption
          premium, if any, and accrued interest to the date fixed for
          redemption) of the $5,000 unit or units of principal amount
          called for redemption and (z) delivery to such Owner of a new
          Bond or Bonds in the aggregate principal amount of the unredeemed
          balance of the principal amount of any such Bond.  Bonds
          representing the unredeemed balance of the principal amount of
          any such Bond shall be delivered to the Owner thereof, without
          charge therefor.  If the Owner of any such Bond of a denomination
          greater than $5,000 shall fail to present such Bond to the Paying
          Agent or any Co-Paying Agent for payment and exchange as
          aforesaid, such Bond shall, nevertheless, become due and payable
          on the date fixed for redemption to the extent of the $5,000 unit
          or units of principal amount called for redemption (and to that
          extent only).

               Section 3.03.  Procedure for Redemption.  (a) In the event
          any of the Bonds are called for redemption, the Trustee shall
          give notice, in the name of the Authority, of the redemption of
          such Bonds, which notice shall (i) specify the Bonds to be
          redeemed, the redemption date, the redemption price, and the
          place or places where amounts due upon such redemption will be
          payable (which shall be the Principal Office of the Paying Agent
          or any Co-Paying Agent) and, if less than all of the Bonds are to
          be redeemed, the numbers of the Bonds to be redeemed, and the
          portion of the principal amount of any Bond to be redeemed in
          part, (ii) state any condition to such redemption and (iii) state
          that on the redemption date, and upon the satisfaction of any
          such condition, the Bonds or portions thereof to be redeemed
          shall cease to bear interest.  Such notice may set forth any
          additional information relating to such redemption.  Such notice
          shall be given by Mail at least thirty (30) days prior to the
          date fixed for redemption to the Owners of the Bonds to be
          redeemed; provided, however, that failure duly to give such
          Notice by Mail, or any defect therein, shall not affect the
          validity of any proceedings for the redemption of Bonds as to
          which there shall have been no such failure or defect.  If a
          notice of redemption shall be unconditional, or if the conditions
          of a conditional notice or redemption shall have been satisfied,
          then upon presentation and surrender of Bonds so called for
          redemption at the place or places of payment, such Bonds shall be
          redeemed.  The Trustee shall promptly deliver to the Company a
          copy of each such notice of redemption.

               (b) With respect to any notice of redemption of Bonds in
          accordance with subsection (a) or (b) of Section 3.01 hereof,
          unless, upon the giving of such notice, such Bonds shall be
          deemed to have been paid within the meaning of Article VIII
          hereof, such notice shall state that such redemption shall be
          conditional upon the receipt, by the Trustee at or prior to the
          opening of business on the date fixed for such redemption, of
          moneys sufficient to pay the principal of and premium, if any,
          and interest on such Bonds to be redeemed, and that if such
          moneys shall not have been so received said notice shall be of no
          force and effect and the Authority shall not be required to
          redeem such Bonds.  In the event that such notice of redemption
          contains such a condition and such moneys are not so received,
          the redemption shall not be made and the Trustee shall within a
          reasonable time thereafter give notice, in the manner in which
          the notice of redemption was given, that such moneys were not so
          received.

               (c)  Any Bonds and portions of Bonds which have been duly
          selected for redemption shall cease to bear interest on the
          specified redemption date provided that moneys sufficient to pay
          the principal of, premium, if any, and interest on such Bonds
          shall be on deposit with the Trustee on the date fixed for
          redemption so that such Bonds will be deemed to be paid in
          accordance with Article VIII hereof.

               Section 3.04.  Payment of Redemption Price.  For the
          redemption of any of the Bonds, the Authority shall cause to be
          deposited in the Bond Fund, on the redemption date, solely out of
          the Receipts and Revenues of the Authority from the Loan
          Agreement, an amount sufficient to pay the principal of and
          premium, if any, and interest to become due on such redemption
          date.  The obligation of the Authority to cause any such deposit
          to be made hereunder shall be reduced by the amount of moneys in
          the Bond Fund available on such redemption date for payment of
          the principal of and premium, if any, and accrued interest on the
          Bonds to be redeemed.

               Section 3.05.  No Partial Redemption After Default. 
          Anything in this Indenture to the contrary notwithstanding, if
          there shall have occurred and be continuing an Event of Default
          defined in clause (a) or (b) of the first paragraph of Section
          9.01 hereof, there shall be no redemption of less than all of the
          Bonds at the time Outstanding other than a partial redemption in
          connection with an offer by the Company to purchase all Bonds
          Outstanding as contemplated in the first proviso to the first
          sentence of Section 3.02 hereof.


                                      ARTICLE IV

                                    THE BOND FUND

               Section 4.01.  Creation of Bond Fund.  There is hereby
          created and established with the Trustee a trust fund in the name
          of the Authority to be designated "The Industrial Development
          Authority of The County of Pima Industrial Development Revenue
          Bonds, 1997 Series C (Tucson Electric Power Company Project) Bond
          Fund".  The Trustee shall establish and maintain within the Bond
          Fund such segregated subaccounts as may be requested by an
          Authorized Company Representative.  The Bond Fund, and all moneys
          and certificated securities therein, shall be kept in the
          possession of the Trustee.

               Section 4.02.  Liens.  The Authority shall not create any
          lien upon the Bond Fund or upon the Receipts and Revenues of the
          Authority from the Loan Agreement other than the lien hereby
          created.

               Section 4.03.  Deposits into Bond Fund.  (a) There shall be
          deposited into the Bond Fund:

                    (i) the accrued interest, if any, on the Bonds accrued
               to the date of delivery thereof and paid by the initial
               purchasers thereof;

                    (ii) all Loan Payments; and

                    (iii) all other moneys received by the Trustee under
               and pursuant to any provision of the Loan Agreement, other
               than Sections 5.03, 5.04 and 8.05 thereof, or from any other
               source when accompanied by directions by the Company that
               such moneys are to be paid into the Bond Fund.

               (b) All income or other gain from the investment of moneys
          in the Bond Fund shall be deposited into the Bond Fund.

               Section 4.04.  Use of Moneys in Bond Fund.  Moneys, if any,
          paid into the Bond Fund pursuant to clause (i) of Section 4.03(a)
          hereof shall be applied to the payment of interest on the Bonds. 
          Except as otherwise provided in Sections 4.06, 9.01 and 10.04
          hereof, all other moneys in the Bond Fund constituting part of
          the Trust Estate shall be used solely for the payment of the
          principal of and premium, if any, and interest on the Bonds as
          the same shall become due and payable at maturity, upon
          redemption or otherwise.

               Section 4.05.  Custody of Bond Fund; Withdrawal of Moneys. 
          The Bond Fund shall be in the custody of the Trustee but in the
          name of the Authority and the Authority hereby authorizes and
          directs the Trustee to withdraw from the Bond Fund and furnish to
          the Paying Agent funds constituting part of the Trust Estate
          sufficient to pay the principal of and premium, if any, and
          interest on the Bonds as the same shall become due and payable,
          and to withdraw from the Bond Fund funds sufficient to pay any
          other amounts payable therefrom as the same shall become due and
          payable.

               Section 4.06.  Bonds Not Presented for Payment.  In the
          event any Bonds shall not be presented for payment when the
          principal thereof and premium, if any, thereon become due, either
          at maturity or at the date fixed for redemption thereof or
          otherwise, if moneys sufficient to pay such Bonds are held by the
          Paying Agent or any Co-Paying Agent for the benefit of the Owners
          thereof, the Paying Agent shall segregate and hold such moneys in
          trust, without liability for interest thereon, for the benefit of
          the Owners of such Bonds, who shall, except as provided in the
          following paragraph, thereafter be restricted exclusively to such
          fund or funds for the satisfaction of any claim of whatever
          nature on their part under this Indenture or relating to said
          Bonds.

               Any moneys which the Paying Agent shall segregate and hold
          in trust for the payment of the principal of and premium, if any,
          or interest on any Bond and remaining unclaimed for one year
          after such principal, premium, if any, or interest has become due
          and payable shall, upon the Company's written request to the
          Paying Agent, be paid to the Company, with notice to the Trustee
          of such action; provided, however, that before the Paying Agent
          shall be required to make any such repayment, the Paying Agent
          shall, at the expense of the Company cause notice to be given
          once by Publication to the effect that such money remains
          unclaimed and that, after a date specified therein, which shall
          not be less than thirty (30) days from the date of such notice by
          Publication, any unclaimed balance of such moneys then remaining
          will be paid to the Company.  After the payment of such unclaimed
          moneys to the Company, the Owner of such Bond shall thereafter
          look only to the Company for the payment thereof, and all
          liability of the Authority, the Trustee and the Paying Agent with
          respect to such moneys shall thereupon cease.

               Section 4.07.  Moneys Held in Trust.  All moneys and
          Investment Securities held by the Trustee in the Bond Fund, and
          all moneys required to be deposited with or paid to the Trustee
          for deposit into the Bond Fund, and all moneys withdrawn from the
          Bond Fund and held by the Trustee, the Paying Agent, any
          Co-Paying Agent, shall be held by the Trustee, the Paying Agent
          or any Co-Paying Agent, as the case may be, in trust, and such
          moneys and Investment Securities (other than moneys held pursuant
          to Section 4.06 hereof and moneys or Investment Securities held
          in the Rebate Fund established in furtherance of the obligations
          of the Company under clause (b) of Section 6.04 of the Loan
          Agreement), while so held or so required to be deposited or paid,
          shall constitute part of the Trust Estate and be subject to the
          lien and security interest created hereby in favor of the
          Trustee, for the benefit of the Owners from time to time of the
          Bonds.  The Company shall have no right, title or interest in the
          Bond Fund, except such rights as may arise after the right, title
          and interest of the Trustee in and to the Trust Estate and all
          covenants, agreements and other obligations of the Authority
          under this Indenture shall have ceased, terminated and become
          void and shall have been satisfied and discharged in accordance
          with Article VIII hereof.

                                      ARTICLE V

                               DISPOSITION OF PROCEEDS

               Section 5.01.  Disposition of Proceeds.  The proceeds from
          the issuance and sale of the Bonds shall be applied as provided
          in Section 4.03 of the Loan Agreement.


                                      ARTICLE VI

                                     INVESTMENTS

               Section 6.01.  Investments.  The moneys in the Bond Fund
          shall, at the direction of the Company, be invested and
          reinvested in Investment Securities.  Any Investment Securities
          may be purchased subject to options or other rights in third
          parties to acquire the same.  Subject to the further provisions
          of this Section 6.01, such investments shall be made by the
          Trustee as directed and designated by the Company in a
          certificate of, or telephonic advice promptly confirmed by a
          certificate of, an Authorized Company Representative.  As and
          when any amounts thus invested may be needed for disbursements
          from the Bond Fund, the Trustee shall request the Company to
          designate such investments to be sold or otherwise converted into
          cash to the credit of the Bond Fund as shall be sufficient to
          meet such disbursement requirements and shall then follow any
          directions in respect thereto of an Authorized Company
          Representative.  As long as no Event of Default (as defined in
          Section 9.01 hereof) shall have occurred and be continuing, the
          Company shall have the right to designate the investments to be
          sold and to otherwise direct the Trustee in the sale or
          conversion to cash of the investments made with the moneys in the
          Bond Fund, provided that the Trustee shall be entitled to
          conclusively assume the absence of any such Event of Default
          unless it has notice thereof within the meaning of Section 10.05
          hereof.


                                     ARTICLE VII

                                  GENERAL COVENANTS

               Section 7.01.  No General Obligations.  Each and every
          covenant herein made, including all covenants made in the various
          sections of this Article VII, is predicated upon the condition
          that neither Pima County, Arizona nor the State of Arizona shall
          in any event be liable for the payment of the principal of, or
          premium, if any, or interest on the Bonds or for the performance
          of any pledge, mortgage, obligation or agreement created by or
          arising out of this Indenture or the issuance of the Bonds, and
          further that neither the Bonds, nor the premium, if any, or
          interest thereon, nor any such obligation or agreement of the
          Authority shall be construed to constitute an indebtedness of
          Pima County, Arizona or the State of Arizona within the meaning
          of any constitutional or statutory provisions whatsoever.  The
          Bonds and the interest and premium, if any, thereon shall be
          limited obligations of the Authority payable solely from the
          Receipts and Revenues of the Authority from the Loan Agreement
          and the other moneys pledged therefor.

               The Authority shall promptly cause to be paid, solely from
          the sources stated herein, the principal of and premium, if any,
          and interest on every Bond issued under this Indenture at the
          place, on the dates and in the manner provided herein and in said
          Bonds according to the true intent and meaning thereof.

               Section 7.02.  Performance of Covenants of the Authority;
          Representations.  The Authority shall faithfully perform at all
          times any and all covenants, undertakings, stipulations and
          provisions contained in this Indenture, in any and every Bond
          executed, authenticated and delivered hereunder, and in all
          proceedings pertaining thereto.  The Authority represents that it
          is duly authorized under the Constitution and laws of the State
          of Arizona to issue the Bonds authorized hereby, to enter into
          the Loan Agreement and this Indenture, and to pledge and assign
          to the Trustee the Trust Estate, and that the Bonds in the hands
          of the Owners thereof are and will be valid and binding limited
          obligations of the Authority.

               Section 7.03.  Maintenance of Rights and Powers; Compliance
          with Laws.  The Authority shall at all times use its best efforts
          to maintain its corporate existence or assure the assumption of
          its obligations under this Indenture by any public body
          succeeding to its powers under the Act; and it shall at all times
          use its best efforts to comply with all valid acts, rules,
          regulations, orders and directions of any legislative, executive,
          administrative or judicial body known to it to be applicable to
          the Loan Agreement and this Indenture.

               Section 7.04.  Enforcement of Obligations of the Company;
          Amendments.  Upon receipt of written notification from the
          Trustee, the Authority shall cooperate with the Trustee in
          enforcing the obligation of the Company to pay or cause to be
          paid all the payments and other costs and charges payable by the
          Company under the Loan Agreement.  The Authority shall not enter
          into any agreement with the Company amending the Loan Agreement
          without the prior written consent of the Trustee and compliance
          with Sections 12.06 and 12.07 of this Indenture (a revision to
          Exhibit A to the Loan Agreement not being deemed an amendment for
          purposes of this Section).

               Section 7.05.  Further Instruments.  The Authority shall,
          upon the reasonable request of the Trustee, from time to time
          execute and deliver such further instruments and take such
          further action as may be reasonable and as may be required to
          carry out the purposes of this Indenture; provided, however, that
          no such instruments or actions shall pledge the credit or taxing
          power of the State of Arizona, Pima County, the Authority or any
          other political subdivision of said State.

               Section 7.06.  No Disposition of Trust Estate.  Except as
          permitted by this Indenture, the Authority shall not sell, lease,
          pledge, assign or otherwise dispose of or encumber its interest
          in the Trust Estate and will promptly pay or cause to be
          discharged or make adequate provision to discharge any lien or
          charge on any part thereof not permitted hereby.

               Section 7.07.  Financing Statements.  The Authority and the
          Trustee shall cooperate with the Company in causing appropriate
          financing statements naming, the Trustee as pledgee of the
          Receipts and Revenues of the Authority from the Loan Agreement
          and of the other moneys pledged under the Indenture for the
          payment of the principal of and premium, if any, and interest on
          the Bonds, and as pledgee and assignee of the balance of the
          Trust Estate, and the Authority shall cooperate with the Trustee
          and the Company in causing appropriate continuation statements to
          be duly filed and recorded in the appropriate state and county
          offices as required by the provisions of the Uniform Commercial
          Code or other similar law as adopted in the State of Arizona and
          any other applicable jurisdiction, as from time to time amended,
          in order to perfect and maintain the security interests created
          by this Indenture.

               Section 7.08.  Tax Covenants; Rebate Fund.  (a)  The
          Authority covenants for the benefit of all Owners from time to
          time of the Bonds that it will not directly or indirectly use or
          (to the extent within its control), permit the use of, the
          proceeds of any of the Bonds or any other funds of the Authority,
          or take or omit to take any other action, if and to the extent
          that such use, or the taking or omission to take such action,
          would cause any of the Bonds to be "arbitrage bonds" within the
          meaning of Section 148 of the Code or otherwise subject to
          federal income taxation by reason of Sections 103 and 141 through
          150 of the Code or Section 103 of the 1954 Code, as applicable,
          and any applicable regulations promulgated thereunder.  To that
          end the Authority covenants to comply with all covenants set
          forth in the Tax Agreement, which is hereby incorporated herein
          by reference as though fully set forth herein.

               (b)  The Trustee shall establish and maintain a fund
          separate from any other fund established and maintained hereunder
          designated "The Industrial Development Authority of the County of
          Pima Industrial Development Revenue Bonds, 1997 Series C (Tucson
          Electric Power Company Project) Rebate Fund" (herein called the
          "Rebate Fund") in accordance with the provisions of the Tax
          Agreement.  Within the Rebate Fund, the Trustee shall maintain
          such accounts as shall be directed by the Company in order for
          the Authority and the Company to comply with the provisions of
          the Tax Agreement.  Subject to the transfer provisions provided
          in paragraph (c) below, all money at any time deposited in the
          Rebate Fund shall be held by the Trustee in trust, to the extent
          required to satisfy the Rebate Requirement (as defined in the Tax
          Agreement), for payment to the United States of America, and
          neither the Company, the Authority or the Owners shall have any
          rights in or claim to such moneys.  All amounts deposited into or
          on deposit in the Rebate Fund shall be governed by this Section
          7.08, by Section 6.04 of the Loan Agreement and by the Tax
          Agreement.  The Trustee shall conclusively be deemed to have
          complied with such provisions if it follows the directions of the
          Company, including supplying all necessary information in the
          manner set forth in the Tax Agreement, and shall not be required
          to take any actions thereunder in the absence of written
          directions from the Company.

               (c)  Upon receipt of the Company's written instructions, the
          Trustee shall remit part or all of the balances in the Rebate
          Fund to the United States of America, as so directed.  In
          addition, if the Company so directs, the Trustee shall deposit
          moneys into or transfer moneys out of the Rebate Fund from or
          into such accounts or funds as directed by the Company's written
          directions.  Any funds remaining in the Rebate Fund after all of
          the Bonds shall have been paid and any Rebate Requirement shall
          have been satisfied, or provision therefor reasonably
          satisfactory to the Trustee shall have been made, shall be
          withdrawn and remitted to the Company.

               (d)  Notwithstanding any provision of this Indenture, the
          obligation to remit the Rebate Requirement to the United States
          of America and to comply with all other requirements of this
          Section 7.08, Section 6.04 of the Loan Agreement and the Tax
          Agreement shall survive the payment of the Bonds and the
          satisfaction and discharge of this Indenture.

               Section 7.09.  Notices of Trustee.  The Trustee shall give
          notice to both the Authority and the Company whenever it is
          required hereby to give notice to either and, additionally, shall
          furnish to the Authority and the Company copies of any Notice by
          Mail or Publication given by it pursuant to any provision hereof.


                                     ARTICLE VIII

                                      DEFEASANCE

               Section 8.01.  Defeasance.  If the Authority shall pay or
          cause to be paid to the Owner of any Bond secured hereby the
          principal of and premium, if any, and interest due and payable,
          and thereafter to become due and payable, upon such Bond or any
          portion of such Bond in the principal amount of $5,000 or any
          integral multiple thereof, such Bond or portion thereof shall
          cease to be entitled to any lien, benefit or security under this
          Indenture.  If the Authority shall pay or cause to be paid to the
          Owners of all the Bonds secured hereby the principal of and
          premium, if any, and interest due and payable, and thereafter to
          become due and payable, thereon, and shall pay or cause to be
          paid all other sums payable hereunder including, without
          limitation, amounts payable pursuant to Section 10.04 hereof,
          then, and in that case, the right, title and interest of the
          Trustee in and to the Trust Estate shall thereupon cease,
          terminate and become void.  In such event, the Trustee shall
          assign, transfer and turn over to the Company the Trust Estate,
          including, without limitation, any surplus in the Bond Fund and
          any balance remaining in any other fund created under this
          Indenture.

               All or any portion of Outstanding Bonds or portions of Bonds
          in principal amounts of $5,000 or any integral multiple thereof,
          shall prior to the maturity or redemption date thereof be deemed
          to have been paid within the meaning and with the effect
          expressed in this Article VIII, and the entire indebtedness of
          the Authority with respect thereof shall be satisfied and
          discharged, when

                    (a) in the event said Bonds or portions thereof have
               been selected for redemption in accordance with Section 3.02
               hereof, the Trustee shall have given, or the Company shall
               have given to the Trustee in form satisfactory to it
               irrevocable instructions to give, on a date in accordance
               with the provisions of Section 3.03 hereof, notice of
               redemption of such Bonds or portions thereof,

                    (b) there shall have been deposited with the Trustee
               either moneys in an amount which shall be sufficient, or
               Government Obligations which shall not contain provisions
               permitting the redemption thereof at the option of the
               issuer, the principal of and the interest on which, when
               due, and without regard to any reinvestment thereof, will
               provide moneys which, together with the moneys, if any,
               deposited with or held by the Trustee, shall be sufficient,
               to pay when due the principal of and premium, if any, and
               interest due and to become due on said Bonds or portions
               thereof on and prior to the redemption date or maturity date
               thereof, as the case may be, and

                    (c) in the event said Bonds or portions thereof do not
               mature and are not to be redeemed within the next succeeding
               sixty (60) days, the Company shall have given the Trustee in
               form satisfactory to it irrevocable instructions to give, as
               soon as practicable in the same manner as a notice of
               redemption is given pursuant to Section 3.03 hereof, a
               notice to the Owners of said Bonds or portions thereof that
               the deposit required by clause (b) above has been made with
               the Trustee and that said Bonds or portions thereof are
               deemed to have been paid in accordance with this Article
               VIII and stating the maturity or redemption date upon which
               moneys are to be available for the payment of the principal
               of and premium, if any, and interest on said Bonds or
               portions thereof.

               Neither the Government Obligations nor moneys deposited with
          the Trustee pursuant to this Article VIII nor principal or
          interest payments on any such Government Obligations shall be
          withdrawn or used for any purpose other than, and such Government
          Obligations, moneys and principal or interest payments shall be
          held in trust for, the payment of the principal of and premium,
          if any, and interest on said Bonds or portions thereof; provided,
          that any cash received from such principal or interest payments
          on such Government Obligations deposited with the Trustee, if not
          then needed for such purposes, shall, to the extent practicable,
          be invested in Government Obligations of the type described in
          clause (b) of the preceding paragraph maturing at times and in
          amounts sufficient to pay when due the principal of and premium,
          if any, and interest to become due on said Bonds or portions
          thereof on and prior to such redemption date or maturity date
          thereof, as the case may be, and interest earned from such
          reinvestments shall be paid over to the Company, as received by
          the Trustee, free and clear of any trust, lien or pledge
          hereunder.  If payment of less than all the Bonds is to be
          provided for in the manner and with the effect provided in this
          Article VIII, the Trustee shall select such Bonds or portions of
          Bonds in the manner specified by Section 3.02 hereof for
          selection for redemption of less than all Bonds in the principal
          amount designated to the Trustee by the Company.  At or prior to
          the time of the deposit of any Government Obligations with the
          Trustee pursuant to this Section 8.01, the Company shall provide
          the Trustee with a certificate of an accountant or an accounting
          firm as to the sufficiency of such Government Obligations to pay
          when due the principal of and premium, if any, and interest due
          and to become due as set forth in clause (b) of the preceding
          paragraph.


                                      ARTICLE IX

                                DEFAULTS AND REMEDIES

               Section 9.01.  Events of Default.  Each of the following
          events shall constitute and is referred to in this Indenture as
          an "Event of Default":

                    (a) a failure to pay the principal of or premium, if
               any, on any of the Bonds when the same shall become due and
               payable at maturity, upon redemption or otherwise;

                    (b) a failure to pay an installment of interest on any
               of the Bonds after such interest shall have become due and
               payable for a period of thirty (30) days;

                    (c) a failure by the Authority to observe and perform
               any covenant, condition, agreement or provision (other than
               as specified in clauses (a) and (b) of this Section 9.01)
               contained in the Bonds or in this Indenture on the part of
               the Authority to be observed or performed, which failure
               shall continue for a period of sixty (60) days after written
               notice, specifying such failure and requesting that it be
               remedied, shall have been given to the Authority and the
               Company by the Trustee, which may give such notice in its
               discretion and which shall give such notice at the written
               request of Owners of not less than 33% in principal amount
               of the Bonds then Outstanding, unless the Trustee, or the
               Trustee and Owners of a principal amount of Bonds not less
               than the principal amount of Bonds the Owners of which
               requested that such notice be given, as the case may be,
               shall agree in writing to an extension of such period prior
               to its expiration; provided, however, that the Trustee, or
               the Trustee and the Owners of such principal amount of
               Bonds, as the case may be, shall be deemed to have agreed to
               an extension of such period if corrective action is
               initiated by the Authority, or the Company on behalf of the
               Authority, within such period and is being diligently
               pursued.

               Upon the occurrence and continuance of any Event of Default
          described in clause (a) or (b) of the preceding paragraph, the
          Trustee may, and at the written request of Owners of not less
          than 33% in principal amount of Bonds then Outstanding shall, by
          written notice to the Authority and the Company, declare the
          Bonds to be immediately due and payable, whereupon they shall,
          without further action, become and be immediately due and
          payable, anything in this Indenture or in the Bonds to the
          contrary notwithstanding, and the Trustee shall give notice
          thereof by Mail to all Owners of Outstanding Bonds.

               The provisions of the preceding paragraph, however, are
          subject to the condition that if, after the principal of the
          Bonds shall have been so declared to be due and payable, and
          before any judgment or decree for the payment of the moneys due
          shall have been obtained or entered as hereinafter provided, the
          Authority shall cause to be deposited with the Trustee a sum
          sufficient to pay all matured installments of interest upon all
          Bonds and the principal of any and all Bonds which shall have
          become due otherwise than by reason of such declaration (with
          interest upon such principal and, to the extent permissible by
          law, on overdue installments of interest, at the rate per annum
          borne by the Bonds) and such amounts as shall be sufficient to
          cover reasonable compensation and reimbursement of expenses
          payable to the Trustee and any predecessor Trustee, and all
          Events of Default hereunder other than nonpayment of the
          principal of Bonds which shall have become due by said
          declaration shall have been remedied, then, in every such case,
          such Event of Default shall be deemed waived and such declaration
          and its consequences rescinded and annulled, and the Trustee
          shall promptly give written notice of such waiver, rescission and
          annulment to the Authority and the Company, and, if notice of the
          acceleration of the Bonds shall have been given to the Owners of
          the Bonds, shall give notice thereof by Mail to all Owners of
          Outstanding Bonds; but no such waiver, rescission and annulment
          shall extend to or affect any subsequent Event of Default or
          impair any right or remedy consequent thereon.

               Section 9.02.  Remedies.  Upon the occurrence and
          continuance of any Event of Default, then and in every such case
          the Trustee in its discretion may, and upon the written request
          of Owners of not less than a majority in principal amount of the
          Bonds then Outstanding and receipt of indemnity to its
          satisfaction shall, in its own name and as the Trustee of an
          express trust:

                    (a) by mandamus, or other suit, action or proceeding at
               law or in equity, enforce all rights of the Owners of the
               Bonds, and require the Authority or the Company to carry out
               any agreements with or for the benefit of such Owners and to
               perform its or their duties under the Act, the Loan
               Agreement and this Indenture;

                    (b) bring suit upon the Bonds; or

                    (c) by action or suit in equity enjoin any acts or
               things which may be unlawful or in violation of the rights
               of the Owners of the Bonds.

               Section 9.03.  Restoration to Former Position.  In the event
          that any proceeding taken by the Trustee to enforce any right
          under this Indenture shall have been discontinued or abandoned
          for any reason, or shall have been determined adversely to the
          Trustee, then the Authority, the Trustee and the Owners shall be
          restored, subject to any determination in such proceeding, to
          their former positions and rights hereunder, respectively, and
          all rights, remedies and powers of the Trustee shall continue as
          though no such proceeding had been taken.

               Section 9.04.  Owners' Right to Direct Proceedings. 
          Anything in this Indenture to the contrary notwithstanding, the
          Owners of a majority in principal amount of the Bonds then
          Outstanding hereunder shall have the right, by an instrument in
          writing executed and delivered to the Trustee, to direct the
          time, method and place of conducting all remedial proceedings
          available to the Trustee under this Indenture or exercising any
          trust or power conferred on the Trustee by this Indenture;
          provided, however, that such direction shall not be otherwise
          than in accordance with law and the provisions of this Indenture
          and that the Trustee shall have the right (but not the
          obligation) to decline to follow any such direction if the
          Trustee, being advised by counsel, shall determine that the
          action or proceeding so directed may not lawfully be taken, or if
          the Trustee in good faith shall determine that the action or
          proceedings so directed would involve the Trustee in personal
          liability or if the Trustee in good faith shall so determine that
          the actions or forbearances specified in or pursuant to such
          direction would be unduly prejudicial to the interests of Owners
          not joining in the giving of said direction, it being understood
          that the Trustee shall have no duty to ascertain whether or not
          such actions or forbearances are unduly prejudicial to such
          Owners.

               Section 9.05.  Limitation on Owners' Right to Institute
          Proceedings.  No Owner of Bonds shall have any right to institute
          any suit, action or proceeding in equity or at law for the
          execution of any trust or power hereunder, or any other remedy
          hereunder or on said Bonds, unless such Owner previously shall
          have given to the Trustee written notice of an Event of Default
          as hereinabove provided and unless the Owners of not less than a
          majority in principal amount of the Bonds then Outstanding shall
          have made written request of the Trustee so to do, after the
          right to institute said suit, action or proceeding shall have
          accrued, and shall have afforded the Trustee a reasonable
          opportunity to proceed to institute the same in either its or
          their name, and unless there also shall have been offered to the
          Trustee security and indemnity satisfactory to it against the
          costs, expenses and liabilities to be incurred therein or
          thereby, and the Trustee shall not have complied with such
          request within a reasonable time; and such notification, request
          and offer of indemnity are hereby declared in every such case, at
          the option of the Trustee, to be conditions precedent to the
          institution of said suit, action or proceeding; it being
          understood and intended that no one or more of the Owners of the
          Bonds shall have any right in any manner whatever by his or their
          action to affect, disturb or prejudice the security of this
          Indenture, or to enforce any right hereunder or under the Bonds,
          except in the manner herein provided, and that all suits, actions
          and proceedings at law or in equity shall be instituted, had and
          maintained in the manner herein provided and for the equal
          benefit of all Owners of the Bonds.

               Section 9.06.  No Impairment of Right to Enforce Payment. 
          Notwithstanding any other provision in this Indenture, the right
          of any Owner of a Bond to receive payment of the principal of and
          premium, if any, and interest on such Bond, on or after the
          respective due dates expressed therein, or to institute suit for
          the enforcement of any such payment on or after such respective
          dates, shall not be impaired or affected without the consent of
          such Owner.

               Section 9.07.  Proceedings by Trustee without Possession of
          Bonds.  All rights of action under this Indenture or under any of
          the Bonds secured hereby which are enforceable by the Trustee may
          be enforced by it without the possession of any of the Bonds, or
          the production thereof on the trial or other proceedings relative
          thereto, and any such suit, action or proceeding instituted by
          the Trustee shall be brought in its name for the equal and
          ratable benefit of the Owners of the Bonds, subject to the
          provisions of this Indenture.

               Section 9.08.  No Remedy Exclusive.  No remedy herein
          conferred upon or reserved to the Trustee or to the Owners of the
          Bonds is intended to be exclusive of any other remedy or
          remedies, and each and every such remedy shall be cumulative, and
          shall be in addition to every other remedy given hereunder or
          under the Loan Agreement, now or hereafter existing at law or in
          equity or by statute.

               Section 9.09.  No Waiver of Remedies.  No delay or omission
          of the Trustee or of any Owner of a Bond to exercise any right or
          power accruing upon any default shall impair any such right or
          power or shall be construed to be a waiver of any such default,
          or an acquiescence therein; and every power and remedy given by
          this Article IX to the Trustee and to the Owners of the Bonds,
          respectively, may be exercised from time to time and as often as
          may be deemed expedient.

               Section 9.10.  Application of Moneys.  Any moneys received
          by the Trustee, by any receiver or by any Owner of a Bond
          pursuant to any right given or action taken under the provisions
          of this Article IX, after payment of the costs and expenses of
          the proceedings resulting in the collection of such moneys and of
          all amounts due to the Trustee and any predecessor Trustee under
          Section 10.04 hereof, shall be deposited in the Bond Fund and all
          moneys so deposited in the Bond Fund during the continuance of an
          Event of Default (other than moneys for the payment of Bonds
          which had matured or otherwise become payable prior to such Event
          of Default or for the payment of interest due prior to such Event
          of Default) shall be applied as follows:

                    (a) Unless the principal of all the Bonds shall have
               become due and payable, all such moneys shall be applied (i)
               first, to the payment to the persons entitled thereto of all
               installments of interest then due on the Bonds, with
               interest on overdue installments, if lawful, at the rate per
               annum borne by the Bonds, in the order of maturity of the
               installments of such interest and, if the amount available
               shall not be sufficient to pay in full any particular
               installment of interest, then to the payment ratably,
               according to the amounts due on such installment, and (ii)
               second, to the payment to the persons entitled thereto of
               the unpaid principal of any of the Bonds which shall have
               become due (other than Bonds called for redemption for the
               payment of which money is held pursuant to the provisions of
               this Indenture), with interest on such Bonds at their rate
               from the respective dates upon which they became due and, if
               the amount available shall not be sufficient to pay in full
               Bonds due on any particular date, together with such
               interest, then to the payment ratably, according to the
               amount of principal and interest due on such date, in each
               case to the persons entitled thereto, without any
               discrimination or privilege.

                    (b) If the principal of all the Bonds shall have become
               due and payable, all such moneys shall be applied to the
               payment of the principal and interest then due and unpaid
               upon the Bonds, with interest on overdue interest and
               principal, as aforesaid, without preference or priority of
               principal over interest or of interest over principal, or of
               any installment of interest over any other installment of
               interest, or of any Bond over any other Bond, ratably,
               according to the amounts due respectively for principal and
               interest, to the persons entitled thereto without any
               discrimination or privilege.

                    (c) If the principal of all the Bonds shall have become
               due and payable, and if acceleration of the maturity of the
               Bonds by reason of such Event of Default shall thereafter
               have been rescinded and annulled under the provisions of
               this Article IX, then, subject to the provisions of clause
               (b) of this Section 9.10 which shall be applicable in the
               event that the principal of all the Bonds shall later become
               due and payable, the moneys shall be applied in accordance
               with the provisions of clause (a) of this Section 9.10.

               Section 9.11.  Severability of Remedies.  It is the purpose
          and intention of this Article IX to provide rights and remedies
          to the Trustee and the Owners which may be lawfully granted under
          the provisions of the Act, but should any right or remedy herein
          granted be held to be unlawful, the Trustee and the Owners shall
          be entitled, as above set forth, to every other right and remedy
          provided in this Indenture and by law.


                                      ARTICLE X

                TRUSTEE; PAYING AGENT AND CO-PAYING AGENTS; REGISTRAR

               Section 10.01.  Acceptance of Trusts.  The Trustee hereby
          accepts and agrees to execute the trusts hereby created, but only
          upon the additional terms set forth in this Article X, to all of
          which the Authority agrees and the respective Owners agree by
          their acceptance of delivery of any of the Bonds.

               Section 10.02.  No Responsibility for Recitals.  The
          recitals, statements and representations contained in this
          Indenture or in the Bonds, save only the Trustee's authentication
          upon the Bonds, are not made by the Trustee, and the Trustee does
          not assume, and shall not have, any responsibility or obligation
          for the correctness of any thereof.  The Trustee makes no
          representation as to the validity or sufficiency of this
          Indenture or the Bonds.

               Section 10.03.  Limitations on Liability.  The Trustee may
          execute any of the trusts or powers hereof and perform the duties
          required of it hereunder by or through attorneys, agents,
          receivers, or employees, and shall be entitled to advice of
          counsel concerning all matters of trust and its duty hereunder,
          and the Trustee shall not be answerable for the default or
          misconduct of any such attorney, agent, receiver, or employee
          selected by it with reasonable care.  The Trustee shall not be
          answerable for the exercise of any discretion or power under this
          Indenture or for anything whatsoever in connection with the trust
          created hereby, except only for its own negligence or bad faith.

               Anything in this Indenture to the contrary notwithstanding,
          the Trustee shall in no event be required to expend or risk its
          own funds or otherwise incur personal financial liability in the
          performance of any of its duties or in the exercise of any of its
          rights or powers, if there shall be reasonable grounds for
          believing that the repayment of such funds or adequate indemnity
          against such liability is not reasonably assured to it.

               Section 10.04.  Compensation, Expenses and Advances.  The
          Trustee, the Paying Agent and any Co-Paying Agent, and the
          Registrar under this Indenture shall be entitled to reasonable
          compensation for their services rendered hereunder (not limited
          by any provision of law regarding the compensation of the trustee
          of an express trust) and to reimbursement for their actual
          out-of-pocket expenses (including counsel fees) reasonably
          incurred in connection therewith except as a result of their
          negligence or bad faith, including, without limitation,
          compensation for any services rendered, and reimbursement for any
          expenses incurred, at and subsequent to the time the Bonds are
          deemed to have been paid in accordance with Article VIII hereof. 
          If the Authority shall fail to perform any of the covenants or
          agreements contained in this Indenture, other than the covenants
          or agreements in respect of the payment of the principal of and
          premium, if any, and interest on the Bonds, the Trustee may, in
          its uncontrolled discretion and without notice to the Owners of
          the Bonds, at any time and from time to time, make advances to
          effect performance of the same on behalf of the Authority, but
          the Trustee shall be under no obligation so to do; and any and
          all such advances may bear interest at a rate per annum not
          exceeding the base rate then in effect for 90-day commercial
          loans by the Trustee or a commercial banking affiliate of the
          Trustee designated as such by the Trustee in the city in which is
          located the Principal Office of the Trustee (or such affiliate,
          as the case may be) to borrowers of the highest credit standing;
          but no such advance shall operate to relieve the Authority from
          any default hereunder.  In Section 5.03 of the Loan Agreement,
          the Company has agreed that it will pay to the Trustee (including
          any predecessor Trustee), the Paying Agent and any Co-Paying
          Agent and the Registrar, such compensation and reimbursement of
          expenses and advances, but the Company may, without creating a
          default hereunder, contest in good faith the reasonableness of
          any such services, expenses and advances.  If the Company shall
          have failed to make any payment to the Trustee or any predecessor
          Trustee under Section 5.03 of the Loan Agreement and such failure
          shall have resulted in an Event of Default under the Loan
          Agreement, the Trustee, and any predecessor Trustee, shall have,
          in addition to any other rights hereunder, a claim, prior to the
          claim of the Owners, for the payment of its compensation and the
          reimbursement of its expenses and any advances made by it, as
          provided in this Section 10.04, upon the moneys and obligations
          in the Bond Fund; provided, however, that neither the Trustee nor
          any predecessor Trustee shall have any such claim upon moneys or
          obligations deposited with or paid to the Trustee for the
          redemption or payment of Bonds which are deemed to have been paid
          in accordance with Article VIII hereof.

               In Section 5.04 of the Loan Agreement, the Company has
          agreed to indemnify the Trustee and any predecessor Trustee to
          the extent provided therein.

               Section 10.05.  Notice of Events of Default.  The Trustee
          shall not be required to take notice, or be deemed to have
          notice, of any default or Event of Default under this Indenture
          other than an Event of Default under clause (a) or (b) of the
          first paragraph of Section 9.01 hereof, unless an officer
          assigned by the Trustee to administer its corporate trust
          business has been specifically notified in writing of such
          default or Event of Default by Owners of at least 33% in
          principal amount of the Bonds then Outstanding.  The Trustee may,
          however, at any time, in its discretion, require of the Authority
          and the Company full information and advice as to the performance
          of any of the covenants, conditions and agreements contained
          herein.

               Section 10.06.  Action by Trustee.  The Trustee shall be
          under no obligation to take any action in respect of any default
          or Event of Default hereunder or toward the execution or
          enforcement of any of the trusts hereby created, or to institute,
          appear in or defend any suit or other proceeding in connection
          therewith, unless requested in writing so to do by Owners of at
          least a majority in principal amount of the Bonds then
          Outstanding, and, if in its opinion such action may tend to
          involve it in expense or liability, unless furnished, from time
          to time as often as it may require, with security and indemnity
          satisfactory to it. The foregoing provisions are intended only
          for the protection of the Trustee, and shall not affect any
          discretion or power given by any provisions of this Indenture to
          the Trustee to take action in respect of any default or Event of
          Default without such notice or request from the Owners of the
          Bonds, or without such security or indemnity.

               Section 10.07.  Good Faith Reliance.  The Trustee shall be
          protected and shall incur no liability in acting or proceeding in
          good faith upon any resolution, notice, telegram, telex,
          facsimile transmission, request, consent, waiver, certificate,
          statement, affidavit, voucher, bond, requisition or other paper
          or document which it shall in good faith believe to be genuine
          and to have been passed or signed by the proper board, body or
          person or to have been prepared and furnished pursuant to any of
          the provisions of this Indenture or the Loan Agreement, or upon
          the written opinion of any attorney, engineer, accountant or
          other expert believed by the Trustee to be qualified in relation
          to the subject matter, and the Trustee shall be under no duty to
          make any investigation or inquiry as to any statements contained
          or matters referred to in any such instrument, but may accept and
          rely upon the same as conclusive evidence of the truth and
          accuracy of such statements.  Neither the Trustee, the Paying
          Agent, any Co-Paying Agent nor the Registrar shall be bound to
          recognize any person as an Owner of a Bond or to take any action
          at his request unless the ownership of such Bond is proved as
          contemplated in Section 11.01 hereof.

               Section 10.08.  Dealings in Bonds and with the Authority and
          the Company.  The Trustee, the Paying Agent, any Co-Paying Agent
          or the Registrar, in its individual or any other capacity, may in
          good faith buy, sell, own, hold and deal in any of the Bonds
          issued hereunder, and may join in any action which any Owner of a
          Bond may be entitled to take with like effect as if it did not
          act in any capacity hereunder.  The Trustee, the Paying Agent,
          any Co-Paying Agent or the Registrar, in its individual or any
          other capacity, either as principal or agent, may also engage in
          or be interested in any financial or other transaction with the
          Authority or the Company, and may act as depositary, trustee, or
          agent for any committee or body of Owners of Bonds secured hereby
          or other obligations of the Authority as freely as if it did not
          act in any capacity hereunder.

               Section 10.09.  Allowance of Interest.  The Trustee may, but
          shall not be obligated to, allow and credit interest upon any
          moneys which it may at any time receive under any of the
          provisions of this Indenture, at such rate, if any, as it
          customarily allows upon similar funds of similar size and under
          similar conditions.  All interest allowed on any such moneys
          shall be credited as provided in Article IV with respect to
          interest on investments.

               Section 10.10.  Construction of Indenture.  The Trustee may
          construe any of the provisions of this Indenture insofar as the
          same may appear to be ambiguous or inconsistent with any other
          provision hereof, and any construction of any such provisions
          hereof by the Trustee in good faith shall be binding upon the
          Owners of the Bonds.

               Section 10.11.  Resignation of Trustee.  The Trustee may
          resign and be discharged of the trusts created by this Indenture
          by executing an instrument in writing resigning such trust and
          specifying the date when such resignation shall take effect, and
          filing the same with the President of the Authority and with the
          Company, not less than forty-five (45) days before the date
          specified in such instrument when such resignation shall take
          effect, and by giving notice of such resignation by Mail to all
          Owners of Bonds.  Such resignation shall take effect on the later
          to occur of (i) the day specified in such instrument and notice,
          unless previously a successor Trustee shall have been appointed
          as hereinafter provided, in which event such resignation shall
          take effect immediately upon the appointment of such successor
          Trustee and (ii) the appointment of a successor Trustee.

               So long as no event which is, or after notice or lapse of
          time, or both, would become, an Event of Default shall have
          occurred and be continuing, if the Authority shall have delivered
          to the Trustee (i) an instrument appointing a successor Trustee,
          effective as of a date specified therein and (ii) an instrument
          of acceptance of such appointment, effective as of such date, by
          such successor Trustee in accordance with Section 10.16, the
          Trustee shall be deemed to have resigned as contemplated in this
          Section, the successor Trustee shall be deemed to have been
          appointed pursuant to subsection (b) of Section 10.13 and such
          appointment shall be deemed to have been accepted as contemplated
          in Section 10.16, all as of such date, and all other provisions
          of this Article X shall be applicable to such resignation,
          appointment and acceptance except to the extent inconsistent with
          this paragraph.  The Authority shall deliver any such instrument
          of appointment at the direction of the Company.

               Section 10.12.  Removal of Trustee.  The Trustee may be
          removed at any time by filing with the Trustee so removed, and
          with the Authority and the Company, an instrument or instruments
          in writing, appointing a successor, or an instrument or
          instruments in writing, consenting to the appointment by the
          Authority (at the direction of the Company) of a successor and
          accompanied by an instrument of appointment by the Authority (at
          the direction of the Company) of such successor, and in any event
          executed by Owners of not less than a majority in principal
          amount of the Bonds then Outstanding, such filing to be made by
          any Owner of a Bond or his duly authorized attorney.

               Section 10.13.  Appointment of Successor Trustee.  (a) In
          case at any time the Trustee shall be removed, or be dissolved,
          or if its property or affairs shall be taken under the control of
          any state or federal court or administrative body because of
          insolvency or bankruptcy, or for any other reason, then a vacancy
          shall forthwith and ipso facto exist and a successor may be
          appointed, and in case at any time the Trustee shall resign or be
          deemed to have resigned, then a successor may be appointed, by
          filing with the Authority and the Company an instrument in
          writing appointing such successor Trustee executed by Owners of
          not less than a majority in principal amount of Bonds then
          Outstanding.  Copies of such instrument shall be promptly
          delivered by the Authority to the predecessor Trustee, to the
          Trustee so appointed and the Company.

               (b)  Until a successor Trustee shall be appointed by the
          Owners of the Bonds as herein authorized, the Authority, shall
          appoint a successor Trustee as directed by the Company.  After
          any appointment by the Authority, it shall cause notice of such
          appointment to be given by Mail to all Owners of Bonds.  Any new
          Trustee so appointed by the Authority shall immediately and
          without further act be superseded by a Trustee appointed by the
          Owners of the Bonds in the manner above provided.

               (c)  No resignation or removal of the Trustee and no
          appointment of a successor Trustee pursuant to this Article shall
          become effective until the acceptance of appointment by the
          successor Trustee.

               Section 10.14.  Qualifications of Successor Trustee.  Every
          successor Trustee (a) shall be a bank or trust company duly
          organized under the laws of the United States or any state or
          territory thereof authorized by law to perform all the duties
          imposed upon it by this Indenture and (b) shall have (or the
          parent holding company of which shall have) a combined capital
          stock, surplus and undivided profits of at least $100,000,000 if
          there can be located, with reasonable effort, such an institution
          willing and able to accept the trust on reasonable and customary
          terms.

               Section 10.15.  Judicial Appointment of Successor Trustee. 
          In case at any time the Trustee shall resign and no appointment
          of a successor Trustee shall be made pursuant to the foregoing
          provisions of this Article X prior to the date specified in the
          notice of resignation as the date when such resignation is to
          take effect, the retiring Trustee may forthwith apply to a court
          of competent jurisdiction for the appointment of a successor
          Trustee.  If no appointment of a successor Trustee shall be made
          pursuant to the foregoing provisions of this Article X within six
          months after a vacancy shall have occurred in the office of
          Trustee, any Owner of a Bond may apply to any court of competent
          jurisdiction to appoint a successor Trustee.  Such court may
          thereupon, after such notice, if any, as it may deem proper and
          prescribe, appoint a successor Trustee.

               Section 10.16.  Acceptance of Trusts by Successor Trustee. 
          Any successor Trustee appointed hereunder shall execute,
          acknowledge and deliver to the Authority an instrument accepting
          such appointment hereunder, and thereupon such successor Trustee,
          without any further act, deed or conveyance, shall become duly
          vested with all the estates, property, rights, powers, trusts,
          duties and obligations of its predecessor in the trust hereunder,
          with like effect as if originally named Trustee herein.  Upon
          request of such Trustee, such predecessor Trustee and the
          Authority shall execute and deliver an instrument transferring to
          such successor Trustee all the estates, property, rights, powers
          and trusts hereunder of such predecessor Trustee and, subject to
          the provisions of Section 10.04 hereof, such predecessor Trustee
          shall pay over to the successor Trustee all moneys and other
          assets at the time held by it hereunder.

               Section 10.17.  Successor by Merger or Consolidation.  Any
          corporation or association into which any Trustee hereunder may
          be merged or converted or with which it may be consolidated, or
          any corporation or association resulting from any merger or
          consolidation to which any Trustee hereunder shall be a party or
          any corporation or association succeeding to the corporate trust
          business of the Trustee, shall be the successor Trustee under
          this Indenture, without the execution or filing of any paper or
          any further act on the part of the parties hereto, anything in
          this Indenture to the contrary notwithstanding.

               If, at the time any such successor to the Trustee shall
          succeed to the trusts created by this Indenture, any of the Bonds
          shall have been authenticated but not delivered, such successor
          Trustee may adopt the certificate of authentication of any
          predecessor Trustee and deliver such Bonds so authenticated; and
          if at that time, any of the Bonds shall not have been
          authenticated, such successor Trustee may authenticate such Bonds
          either in the name of any such predecessor hereunder or in the
          name of such successor; and, in all such cases, such certificate
          of authentication shall have the full force which it is anywhere
          in the Bonds or in this Indenture provided that the certificate
          of authentication of the Trustee shall have; provided, however,
          that the right to adopt the certificate of authentication of any
          predecessor Trustee or to authenticate Bonds in the name of any
          predecessor Trustee shall apply only to its successor or
          successors by merger, conversion or consolidation.

               Section 10.18.  Standard of Care.  Notwithstanding any other
          provisions of this Article X, the Trustee shall, during the
          existence of an Event of Default of which the Trustee has actual
          notice, exercise such of the rights and powers vested in it by
          this Indenture and use the same degree of skill and care in their
          exercise as a prudent man would use and exercise under the
          circumstances in the conduct of his own affairs.

               Section 10.19.  Notice to Owners of Bonds of Event of
          Default.  If an Event of Default occurs of which the Trustee by
          Section 10.05 hereof is required to take notice and deemed to
          have notice, or any other Event of Default occurs of which the
          Trustee has been specifically notified in accordance with Section
          10.05 hereof, and any such Event of Default shall continue for at
          least two days after the Trustee acquires actual notice thereof,
          unless the Trustee shall have theretofore given a notice of
          acceleration pursuant to Section 9.01 hereof, the Trustee shall
          give Notice by Mail to all Owners of Outstanding Bonds.

               Section 10.20.  Intervention in Litigation of the Authority. 
          In any judicial proceeding to which the Authority is a party and
          which in the opinion of the Trustee and its counsel has a
          substantial bearing on the interests of the Owners of Bonds, the
          Trustee may intervene on behalf of the Owners of the Bonds and
          shall, upon receipt of indemnity satisfactory to it, do so if
          requested in writing by Owners of at least a majority in
          principal amount of the Bonds then Outstanding if permitted by
          the court having jurisdiction in the premises.

               Section 10.21.  Paying Agent; Co-Paying Agents.  The
          Authority shall, with the approval of the Company, appoint the
          Paying Agent for the Bonds and may at any time or from time to
          time, with the approval of the Company, appoint one or more
          Co-Paying Agents for the Bonds, subject to the conditions set
          forth in Section 10.22 hereof.  The Paying Agent and each
          Co-Paying Agent shall designate to the Trustee its Principal
          Office and signify its acceptance of the duties and obligations
          imposed upon it hereunder by a written instrument of acceptance
          delivered to the Authority and the Trustee in which such Paying
          Agent or Co-Paying Agent will agree, particularly:

                    (a) to hold all sums held by it for the payment of the
               principal of and premium, if any, or interest on Bonds in
               trust for the benefit of the Owners of the Bonds until such
               sums shall be paid to such Owners or otherwise disposed of
               as herein provided;

                    (b) to keep such books and records as shall be
               consistent with prudent industry practice, to make such
               books and records available for inspection by the Authority,
               the Trustee and the Company at all reasonable times and, in
               the case of a Co-Paying Agent, to promptly furnish copies of
               such books and records to the Paying Agent; and

                    (c) in the case of a Co-Paying Agent, upon the request
               of the Paying Agent, to forthwith deliver to the Paying
               Agent all sums so held in trust by such Co-Paying Agent.

               The Authority shall cooperate with the Trustee and the
          Company to cause the necessary arrangements to be made and to be
          thereafter continued whereby funds derived from the sources
          specified in Sections 4.03 and 4.04 hereof will be made available
          to the Paying Agent and each Co-Paying Agent for the payment when
          due of the principal of, premium, if any, and interest on the
          Bonds.

               Section 10.22.  Qualifications of Paying Agent and Co-Paying
          Agents; Resignation; Removal.  The Paying Agent and any Co-Paying
          Agent shall be a corporation or association duly organized under
          the laws of the United States of America or any state or
          territory thereof, having a combined capital stock, surplus and
          undivided profits of at least $15,000,000 and authorized by law
          to perform all the duties imposed upon it by this Indenture.  The
          Paying Agent and any Co-Paying Agent may at any time resign and
          be discharged of the duties and obligations created by this
          Indenture by giving at least sixty (60) days' notice to the
          Authority, the Company and the Trustee.  The Paying Agent and any
          Co-Paying Agent may be removed at any time, at the direction of
          the Company, by an instrument, signed by the Authority, filed
          with the Paying Agent or such Co-Paying Agent, as the case may
          be, and with the Trustee.

               In the event of the resignation or removal of the Paying
          Agent or any Co-Paying Agent, the Paying Agent or such Co-Paying
          Agent, as the case may be, shall pay over, assign and deliver any
          moneys held by it in such capacity to its successor or, if there
          be no successor, to the Trustee.

               In the event that the Authority shall fail to appoint a
          Paying Agent hereunder, or in the event that the Paying Agent
          shall resign or be removed, or be dissolved, or if the property
          or affairs of the Paying Agent shall be taken under the control
          of any state or federal court or administrative body because of
          bankruptcy or insolvency, or for any other reason, and the
          Authority shall not have appointed its successor as Paying Agent,
          the Trustee shall ipso facto be deemed to be the Paying Agent for
          all purposes of this Indenture until the appointment by the
          Authority of the Paying Agent or successor Paying Agent, as the
          case may be.

               Upon the appointment of a successor Paying Agent, the
          Trustee shall give notice thereof by Mail to all Owners of Bonds.

               Section 10.23.  Registrar.  The Authority shall, with the
          approval of the Company, appoint the Registrar for the Bonds,
          subject to the conditions set forth in Section 10.24 hereof.  The
          Registrar shall designate to the Trustee its Principal Office and
          signify its acceptance of the duties imposed upon it hereunder by
          a written instrument of acceptance delivered to the Authority and
          the Trustee in which such Registrar will agree, particularly, to
          keep such books and records as shall be consistent with prudent
          industry practice and to make such books and records available
          for inspection by the Authority, the Trustee and the Company at
          all reasonable times.

               The Authority shall cooperate with the Trustee and the
          Company to cause the necessary arrangements to be made and to be
          thereafter continued whereby Bonds, executed by the Authority and
          authenticated by the Trustee, shall be made available for
          exchange, registration and registration of transfer at the
          Principal Office of the Registrar.  The Authority shall cooperate
          with the Trustee, the Registrar and the Company to cause the
          necessary arrangements to be made and thereafter continued
          whereby the Paying Agent and any Co-Paying Agent shall be
          furnished such records and other information, at such times, as
          shall be required to enable the Paying Agent and such Co-Paying
          Agent to perform the duties and obligations imposed upon them
          hereunder.

               Section 10.24.  Qualifications of Registrar; Resignation;
          Removal.  The Registrar shall be a corporation or association
          duly organized under the laws of the United States of America or
          any state or territory thereof, having a combined capital stock,
          surplus and undivided profits of at least $15,000,000 and
          authorized by law to perform all the duties imposed upon it by
          this Indenture.  The Registrar may at any time resign and be
          discharged of the duties and obligations created by this
          Indenture by giving at least sixty (60) days' notice to the
          Authority, the Trustee and the Company.  The Registrar may be
          removed at any time, at the direction of the Company, by an
          instrument signed by the Authority filed with the Registrar and
          the Trustee.

               In the event of the resignation or removal of the Registrar,
          the Registrar shall deliver any Bonds held by it in such capacity
          to its successor or, if there be no successor, to the Trustee.

               In the event that the Authority shall fail to appoint a
          Registrar hereunder, or in the event that the Registrar shall
          resign or be removed, or be dissolved, or if the property or
          affairs of the Registrar shall be taken under the control of any
          state or federal court or administrative body because of
          bankruptcy or insolvency, or for any other reason, and the
          Authority shall not have appointed its successor as Registrar,
          the Trustee shall ipso facto be deemed to be the Registrar for
          all purposes of this Indenture until the appointment by the
          Authority of the Registrar or successor Registrar, as the case
          may be.

               Upon the appointment of a successor Registrar, the Trustee
          shall give notice thereof by Mail to all Owners of Bonds.

               Section 10.25.  Several Capacities.  Anything herein to the
          contrary notwithstanding, the same entity may serve hereunder as
          the Trustee, the Paying Agent or a Co-Paying Agent and the
          Registrar and in any combination of such capacities to the extent
          permitted by law.


                                      ARTICLE XI

                   EXECUTION OF INSTRUMENTS BY OWNERS OF BONDS AND
                             PROOF OF OWNERSHIP OF BONDS

               Section 11.01.  Execution of Instruments; Proof of
          Ownership.  Any request, direction, consent or other instrument
          in writing, whether or not required or permitted by this
          Indenture to be signed or executed by Owners of the Bonds, may be
          in any number of concurrent instruments of similar tenor and may
          be signed or executed by Owners of the Bonds or by an agent
          appointed by an instrument in writing.  Proof of the execution of
          any such instrument and of the ownership of Bonds shall be
          sufficient for any purpose of this Indenture and shall be
          conclusive in favor of the Trustee with regard to any action
          taken by it under such instrument if made in the following
          manner:

                    (a) The fact and date of the execution by any person of
               any such instrument may be proved by the certificate of any
               officer in any jurisdiction who, by the laws thereof, has
               power to take acknowledgments within such jurisdiction, to
               the effect that the person signing such instrument
               acknowledged before him the execution thereof, or by an
               affidavit of a witness to such execution.

                    (b) The ownership or former ownership of Bonds shall be
               proved by the registration books kept under the provisions
               of Section 2.08 hereof.

               Nothing contained in this Article XI shall be construed as
          limiting the Trustee to such proof, it being intended that the
          Trustee may accept any other evidence of matters herein stated
          which it may deem sufficient.  Any request or consent of any
          Owner of a Bond shall bind every future Owner of the same Bond or
          any Bond or Bonds issued in lieu thereof in respect of anything
          done by the Trustee or the Authority in pursuance of such request
          or consent.


                                     ARTICLE XII

                MODIFICATION OF THIS INDENTURE AND THE LOAN AGREEMENT

               Section 12.01.  Limitations.  Neither this Indenture nor the
          Loan Agreement shall be modified or amended in any respect
          subsequent to the original issuance of the Bonds except as
          provided in and in accordance with and subject to the provisions
          of this Article XII and Section 7.04 hereof.

               The Trustee may, but shall not be obligated to, enter into
          any Supplemental Indenture which affects the Trustee's own
          rights, duties or immunities under this Indenture or otherwise.

               Section 12.02.  Supplemental Indentures without Owner
          Consent.  The Authority and the Trustee may, from time to time
          and at any time, without the consent of or notice to the Owners
          of the Bonds, enter into Supplemental Indentures as follows:

                    (a) to cure any formal defect, omission, inconsistency
               or ambiguity in this Indenture, provided, however, that such
               cure shall not materially and adversely affect the interests
               of the Owners of the Bonds;

                    (b) to grant to or confer or impose upon the Trustee
               for the benefit of the Owners of the Bonds any additional
               rights, remedies, powers, authority, security, liabilities
               or duties which may lawfully be granted, conferred or
               imposed;

                    (c) to add to the covenants and agreements of, and
               limitations and restrictions upon, the Authority in this
               Indenture other covenants, agreements, limitations and
               restrictions to be observed by the Authority;

                    (d) to confirm, as further assurance, any pledge under,
               and the subjection to any claim, lien or pledge created or
               to be created by, this Indenture, of the Receipts and
               Revenues of the Authority from the Loan Agreement or of any
               other moneys, securities or funds;

                    (e) to authorize a different denomination or
               denominations of the Bonds and to make correlative
               amendments and modifications to this Indenture regarding
               exchange ability of Bonds of different denominations,
               redemptions of portions of Bonds of particular denominations
               and similar amendments and modifications of a technical
               nature;

                    (f) to modify, alter, supplement or amend this
               Indenture in such manner as shall permit the qualification
               hereof under the Trust Indenture Act of 1939, as from time
               to time amended;

                    (g) to modify, alter, supplement or amend this
               Indenture in such manner as shall be necessary, desirable or
               appropriate in order to provide for or eliminate the
               registration and registration of transfer of the Bonds
               through a book-entry or similar method, whether or not the
               Bonds are evidenced by certificates;

                    (h) to modify, alter, amend or supplement this
               Indenture in any other respect which is not materially
               adverse to the Owners and which does not involve a change
               described in clause (i), (ii), (iii) or (iv) of Section
               12.03(a) hereof; and

                    (i) to provide any additional procedures, covenants or
               agreements necessary or desirable to maintain the tax-exempt
               status of interest on the Bonds.

               Before the Authority and the Trustee shall enter into any
          Supplemental Indenture pursuant to this Section 12.02, there
          shall have been delivered to the Trustee an opinion of Bond
          Counsel stating that such Supplemental Indenture is authorized or
          permitted by this Indenture and the Act, complies with their
          respective terms, will, upon the execution and delivery thereof,
          be valid and binding upon the Authority in accordance with its
          terms and will not, in and of itself, adversely affect the
          exclusion from gross income for federal tax purposes of the
          interest on the Bonds.

               Section 12.03.  Supplemental Indentures with Consent of
          Owners.  (a) Except for any Supplemental Indenture entered into
          pursuant to Section 12.02 hereof, subject to the terms and
          provisions contained in this Section 12.03 and Section 12.05 and
          not otherwise, Owners of not less than a majority in aggregate
          principal amount of the Bonds then Outstanding which would be
          adversely affected thereby shall have the right from time to time
          to consent to and approve the execution and delivery by the
          Authority and the Trustee of any Supplemental Indenture deemed
          necessary or desirable by the Authority for the purposes of
          modifying, altering, amending, supplementing or rescinding, in
          any particular, any of the terms or provisions contained in this
          Indenture; provided, however, that, unless approved in writing by
          the Owners of all the Bonds then Outstanding which would be
          adversely affected thereby, nothing herein contained shall
          permit, or be construed as permitting, (i) a change in the times,
          amounts or currency of payment of the principal of or premium, if
          any, or interest on any Outstanding Bond, a reduction in the
          principal amount or redemption price of any Outstanding Bond or a
          change in the rate of interest thereon, or any impairment of the
          right of any Owner to institute suit for the payment of any Bond
          owned by it, or (ii) the creation of a claim or lien upon, or a
          pledge of, the Receipts and Revenues of the Authority from the
          Loan Agreement ranking prior to or on a parity with the claim,
          lien or pledge created by this Indenture (except as referred to
          in Section 10.04 hereof), or (iii) a preference or priority of
          any Bond or Bonds over any other Bond or Bonds, or (iv) a
          reduction in the aggregate principal amount of Bonds the consent
          of the Owners of which is required for any such Supplemental
          Indenture or which is required, under Section 12.07 hereof, for
          any modification, alteration, amendment or supplement to the Loan
          Agreement.

               (b) If at any time the Authority shall request the Trustee
          to enter into any Supplemental Indenture for any of the purposes
          of this Section 12.03, the Trustee shall cause notice of the
          proposed Supplemental Indenture to be given by Mail to all Owners
          of Outstanding Bonds.  Such notice shall briefly set forth the
          nature of the proposed Supplemental Indenture and shall state
          that a copy thereof is on file at the Principal Office of the
          Trustee for inspection by all Owners of Bonds.

               (c) Within two years after the date of the first mailing of
          such notice, the Authority and the Trustee may enter into such
          Supplemental Indenture in substantially the form described in
          such notice only if there shall have first been delivered to the
          Trustee (i) the required consents, in writing, of Owners of Bonds
          and (ii) an opinion of Bond Counsel stating that such
          Supplemental Indenture is authorized or permitted by this
          Indenture and the Act, complies with their respective terms and,
          upon the execution and delivery thereof, will be valid and
          binding upon the Authority in accordance with its terms and will
          not, in and of itself, adversely affect the exclusion from gross
          income for federal tax purposes of the interest on the Bonds.

               (d) If Owners of not less than the percentage of Bonds
          required by this Section 12.03 shall have consented to and
          approved the execution and delivery thereof as herein provided,
          no Owner shall have any right to object to the execution and
          delivery of such Supplemental Indenture, or to object to any of
          the terms and provisions contained therein or the operation
          thereof, or in any manner to question the propriety of the
          execution and delivery thereof, or to enjoin or restrain the
          Authority or the Trustee from executing and delivering the same
          or from taking any action pursuant to the provisions thereof.

               Section 12.04.  Effect of Supplemental Indenture.  Upon the
          execution and delivery of any Supplemental Indenture pursuant to
          the provisions of this Article XII, this Indenture shall be, and
          be deemed to be, modified, altered, amended or supplemented in
          accordance therewith, and the respective rights, duties and
          obligations under this Indenture of the Authority, the Trustee
          and Owners of all Bonds then Outstanding shall thereafter be
          determined, exercised and enforced under this Indenture subject
          in all respects to such modifications, alterations, amendments
          and supplements.

               Section 12.05.  Consent of the Company.  Anything herein to
          the contrary notwithstanding, any Supplemental Indenture under
          this Article XII which affects any rights, powers, agreements or
          obligations of the Company under the Loan Agreement, or requires
          a revision of the Loan Agreement, shall not become effective
          unless and until the Company shall have consented to such
          Supplemental Indenture.

               Section 12.06.  Amendment of Loan Agreement without Consent
          of Owners.  Without the consent of or notice to the Owners of the
          Bonds, the Authority may enter into any Supplemental Loan
          Agreement, and the Trustee may consent thereto, as may be
          required (a) by the provisions of the Loan Agreement and this
          Indenture, (b) for the purpose of curing any formal defect,
          omission, inconsistency or ambiguity therein, (c) to provide any
          additional procedures, covenants or agreements necessary or
          desirable to maintain the tax-exempt status of interest on the
          Bonds, or (d) in connection with any other change therein which
          is not materially adverse to the Owners of the Bonds.  A revision
          of Exhibit A to the Loan Agreement pursuant to Section 3.03
          thereof shall not be deemed a Supplemental Loan Agreement for
          purposes of this Indenture.

               Before the Authority shall enter into, and the Trustee shall
          consent to, any Supplemental Loan Agreement pursuant to this
          Section 12.06, there shall have been delivered to the Trustee an
          opinion of Bond Counsel stating that such Supplemental Loan
          Agreement is authorized or permitted by this Indenture and the
          Act, complies with their respective terms, will, upon the
          execution and delivery thereof, be valid and binding upon the
          Authority and the Company in accordance with its terms and will
          not, in and of itself, adversely affect the exclusion from gross
          income for federal tax purposes of interest on the Bonds.

               Section 12.07.  Amendment of Loan Agreement with Consent of
          Owners.  Except in the case of Supplemental Loan Agreements
          referred to in Section 12.06 hereof, the Authority shall not
          enter into, and the Trustee shall not consent to, any
          Supplemental Loan Agreement without the written approval or
          consent of the Owners of not less than a majority in aggregate
          principal amount of the Bonds then Outstanding which would be
          adversely affected thereby, given and procured as provided in
          Section 12.03 hereof; provided, however, that, unless approved in
          writing by the Owners of all Bonds then Outstanding which would
          be adversely affected thereby, nothing herein contained shall
          permit, or be construed as permitting, a change in the
          obligations of the Company under Section 5.01 of the Loan
          Agreement.  If at any time the Authority or the Company shall
          request the consent of the Trustee to any such proposed
          Supplemental Loan Agreement, the Trustee shall cause notice of
          such proposed Supplemental Loan Agreement to be given in the same
          manner as provided by Section 12.03 hereof with respect to
          Supplemental Indentures.  Such notice shall briefly set forth the
          nature of such proposed Supplemental Loan Agreement and shall
          state that copies of the instrument embodying the same are on
          file at the Principal Office of the Trustee for inspection by all
          Owners of the Bonds.  The Authority may enter into, and the
          Trustee may consent to, any such proposed Supplemental Loan
          Agreement subject to the same conditions, and with the same
          effect, as provided by Section 12.03 hereof with respect to
          Supplemental Indentures.


                                     ARTICLE XIII

                                    MISCELLANEOUS

               Section 13.01.  Successors of the Authority.  In the event
          of the dissolution of the Authority, all the covenants,
          stipulations, promises and agreements in this Indenture
          contained, by or on behalf of, or for the benefit of, the
          Authority, shall bind or inure to the benefit of the successors
          of the Authority from time to time and any entity, officer,
          board, commission, agency or instrumentality to whom or to which
          any power or duty of the Authority shall be transferred.

               Section 13.02.  Parties in Interest.  Except as herein
          otherwise specifically provided, nothing in this Indenture
          expressed or implied is intended or shall be construed to confer
          upon any person, firm or corporation other than the Authority,
          the Company and the Trustee and their successors and assigns and
          the Owners of the Bonds any right, remedy or claim under or by
          reason of this Indenture, this Indenture being intended to be for
          the sole and exclusive benefit of the Authority, the Company and
          the Trustee and their successors and assigns and the Owners of
          the Bonds.

               Section 13.03.  Severability.  In case any one or more of
          the provisions of this Indenture or of the Loan Agreement or of
          the Bonds shall, for any reason, be held to be illegal or
          invalid, such illegality or invalidity shall not affect any other
          provisions of this Indenture or of the Loan Agreement or of such
          Bonds, and this Indenture and the Loan Agreement and such Bonds
          shall be construed and enforced as if such illegal or invalid
          provisions had not been contained herein or therein.

               Section 13.04.  No Personal Liability of Authority
          Officials.  No covenant or agreement contained in the Bonds or in
          this Indenture shall be deemed to be the covenant or agreement of
          any director, official, officer, agent, or employee of the
          Authority in his individual capacity, and neither the members of
          the Board of Directors of the Authority nor any official
          executing the Bonds shall be liable personally on the Bonds or be
          subject to any personal liability or accountability by reason of
          the issuance thereof.

               Section 13.05.  Bonds Owned by the Authority or the Company. 
          In determining whether Owners of the requisite aggregate
          principal amount of the Bonds have concurred in any direction,
          consent or waiver under this Indenture, Bonds which are owned by
          the Authority or the Company or by any person directly or
          indirectly controlling or controlled by or under direct or
          indirect common control with the Company (unless the Authority,
          the Company or such person owns all Bonds which are then
          Outstanding, determined without regard to this Section 13.05)
          shall be disregarded and deemed not to be Outstanding for the
          purpose of any such determination, except that, for the purpose
          of determining whether the Trustee shall be protected in relying
          on any such direction, consent or waiver, only Bonds which the
          Trustee knows are so owned shall be so disregarded.  Upon the
          request of the Trustee, the Company and the Authority shall
          furnish to the Trustee a certificate identifying all Bonds, if
          any, actually known to either of them to be owned or held by or
          for the account of any of the above-described persons, and the
          Trustee shall be entitled to rely on such certificate as
          conclusive evidence of the facts set forth therein and that all
          other Bonds are Outstanding for the purposes of such
          determination.  Bonds so owned which have been pledged in good
          faith may be regarded as Outstanding if the pledgee establishes
          to the satisfaction of the Trustee the pledgee's right so to act
          with respect to such Bonds and that the pledgee is not the
          Authority or the Company or any person directly or indirectly
          controlling or controlled by or under direct or indirect common
          control with the Company. In case of a dispute as to such right,
          any decision by the Trustee taken upon the advice of counsel
          shall be full protection to the Trustee.

               Section 13.06.  Counterparts.  This Indenture may be
          executed in any number of counterparts, each of which, when so
          executed and delivered, shall be an original; but such
          counterparts shall together constitute but one and the same
          Indenture.

               Section 13.07.  Governing Law.  The laws of the State of
          Arizona shall govern the construction and enforcement of this
          Indenture and of all Bonds, except that the laws of the State of
          New York shall govern the construction and enforcement of the
          rights and duties of the Trustee hereunder and the construction
          of Section 13.09 hereof and the computation of any period of
          grace provided herein.

               Section 13.08.  Notices.  Except as otherwise provided in
          this Indenture, all notices, certificates, requests requisitions
          or other communications by the Authority, the Company, the
          Trustee, the Paying Agent, any Co-Paying Agent or the Registrar
          pursuant to this Indenture shall be in writing and shall be
          sufficiently given and shall be deemed given when mailed by
          registered mail, postage prepaid, addressed as follows: If to the
          Authority, c/o Russo, Cox & Russo, P.C., 1820 East River Road,
          Suite 230, Tucson, Arizona 85718; if to the Company, at 220 West
          Sixth Street, Tucson, Arizona 85702, Attention: Treasurer; if to
          the Trustee, at 100 Wall Street, Suite 1600, New York, New York
          10005, Attention: Vice President; if to the Paying Agent, any
          Co-Paying Agent or the Registrar, at the address designated in
          the acceptance of appointment or engagement.  Any of the
          foregoing may, by notice given hereunder to each of the others,
          designate any further or different addresses to which subsequent
          notices, certificates, requests or other communications shall be
          sent hereunder.

               Section 13.09.  Holidays.  If the date for making any
          payment or the last date for performance of any act or the
          exercising of any right, as provided in this Indenture, shall be
          a Saturday, Sunday or a public holiday in the city in which is
          located the Principal Office of the Trustee, such payment may be
          made or act performed or right exercised on the next succeeding
          business day, with the same force and effect as if done on the
          nominal date provided in this Indenture, and no interest shall
          accrue for the period after such nominal date.  If the last day
          of any period of grace, as provided in this Indenture, shall be a
          Saturday, Sunday or a public holiday in the city in which is
          located the Principal Office of the Trustee, the last day of such
          period of grace shall be deemed to be the next succeeding
          business day.

               Section 13.10.  Statutory Notice Regarding Cancellation of
          Contracts.  As required by the provisions of Section 38-511,
          Arizona Revised Statutes, as amended, notice is hereby given that
          political subdivisions of the State of Arizona or any of their
          departments or agencies may, within three (3) years of its
          execution, cancel any contract, without penalty or further
          obligation, made by the political subdivisions or any of their
          departments or agencies on or after September 30, 1988, if any
          person significantly involved in initiating, negotiating,
          securing, drafting or creating the contract on behalf of the
          political subdivisions or any of their departments or agencies
          is, at any time while the contract or any extension of the
          contact is in effect, an employee or agent of any other party to
          the contract in any capacity or a consultant to any other party
          of the contract with respect to the subject matter of the
          contract.

               The Trustee covenants and agrees not to employ as an
          employee, agent or, with respect to the subject matter of this
          Indenture, a consultant, any person actually known by the Trustee
          to be significantly involved in initiating, negotiating,
          securing, drafting or creating such Indenture on behalf of the
          Authority within three (3) years from the execution hereof,
          unless a waiver is provided by the Authority.


          


                IN WITNESS WHEREOF, The Industrial Development Authority of
          the County of Pima has caused this Indenture to be executed by
          its President and First Trust of New York, National Association
          has caused this Indenture to be executed on its behalf by its
          Vice President, all as of the day and year first above written.

                                   THE INDUSTRIAL DEVELOPMENT AUTHORITY
                                   OF THE COUNTY OF PIMA

                                   By:  /s/Stanley Lehman
                                      ---------------------------------
                                      President

                                   FIRST TRUST OF NEW YORK,
                                   NATIONAL ASSOCIATION



                                   By:  /s/ P.J. Crowley
                                      ---------------------------------
                                      Vice President


          


                                                                  EXHIBIT A


                                    (FORM OF BOND)

          No.


                         THE INDUSTRIAL DEVELOPMENT AUTHORITY
                                OF THE COUNTY OF PIMA
                         INDUSTRIAL DEVELOPMENT REVENUE BOND,
                                    1997 SERIES C
                       (TUCSON ELECTRIC POWER COMPANY PROJECT)

          INTEREST RATE (PER ANNUM):
          MATURITY DATE:                               DATED:
          CUSIP:
          REGISTERED OWNER:
          PRINCIPAL AMOUNT:                            DOLLARS


               The Industrial Development Authority of the County of Pima,
          an Arizona nonprofit corporation designated by law as a political
          subdivision of the State of Arizona (the "Authority"), for value
          received, hereby promises to pay (but only out of the Receipts
          and Revenues of the Authority from the Loan Agreement, as
          hereinafter defined, and other moneys pledged therefor) to the
          Registered Owner identified above or registered assigns, on the
          Maturity Date set forth above, upon the presentation and
          surrender hereof, the Principal Amount set forth above and to pay
          (but only out of the Receipts and Revenues of the Authority from
          the Loan Agreement and other moneys pledged therefor), interest
          on said Principal Amount until payment of said Principal Amount
          has been made or duly provided for, from the date hereof, at the
          Interest Rate set forth above, semi-annually on the first days of
          March and September in each year, commencing March 1, 1998. 
          Interest will be calculated on the basis of a 360-day year of
          twelve 30-day months.

               The principal of and premium, if any, on this Bond are
          payable at the principal office of First Trust of New York,
          National Association, as Paying Agent, or at the principal office
          of any co-paying agent appointed in accordance with the Indenture
          (as hereinafter defined), at the option of the Registered Owner
          hereof.  Interest on this Bond is payable by check drawn upon the
          Paying Agent and mailed to the Registered Owner of this Bond as
          of the close of business on the Record Date (as defined in the
          Indenture) at the registered address of such Registered Owner;
          notwithstanding the foregoing, upon request to the Paying Agent
          by a Registered Owner of not less than $1,000,000 in aggregate
          principal amount of Bonds, interest on such Bonds and, after
          presentation and surrender of such Bonds, the principal thereof
          shall be paid to such Registered Owner by wire transfer to the
          account maintained within the continental United States specified
          by such Registered Owner or, if such Registered Owner maintains
          an account with the entity acting as Paying Agent, by deposit
          into such account.  Payment of the principal of and premium, if
          any, and interest on, this Bond shall be in any coin or currency
          of the United States of America as, at the respective times of
          payment, shall be legal tender for the payment of public and
          private debts.

               This Bond is one of the duly authorized Industrial
          Development Revenue Bonds, 1997 Series C (Tucson Electric Power
          Company Project) (the "Bonds") of the Authority, aggregating
          Seventy-Five Million Dollars ($75,000,000) in principal amount,
          issued under and pursuant to the Constitution and laws of the
          State of Arizona, particularly Title 35, Chapter 5, Arizona
          Revised Statutes, as amended (the "Act"), and the Indenture of
          Trust, dated as of September 15, 1997 (the "Indenture"), between
          the Authority and First Trust of New York, National Association,
          as trustee (the "Trustee"), for the purpose of refinancing, by
          payment or redemption of the Authority's Industrial Development
          Revenue Bonds, 1983 Series A (Tucson Electric Power Company
          General Project), or provision therefor, a portion of the costs
          of the acquisition, construction, improvement and equipping of
          certain facilities for the furnishing of electric energy (the
          "Facilities").  Pursuant to the Loan Agreement, dated as of
          September 15, 1997 (the "Loan Agreement"), between the Authority
          and Tucson Electric Power Company, a corporation organized and
          existing under the laws of the State of Arizona (the "Company"),
          the proceeds of the Bonds, other than accrued interest, if any,
          paid by the initial purchasers thereof, will be loaned to the
          Company.

               Neither Pima County, Arizona nor the State of Arizona shall
          in any event be liable for the payment of the principal of or
          premium, if any, or interest on the Bonds, and neither the Bonds,
          nor the premium, if any, or the interest thereon, shall be
          construed to constitute an indebtedness of Pima County, Arizona
          or the State of Arizona within the meaning of any constitutional
          or statutory provisions whatsoever.  The Bonds and the premium,
          if any, and the interest thereon are limited obligations of the
          Authority payable solely from the Receipts and Revenues of the
          Authority from the Loan Agreement and other moneys pledged
          therefor under the Indenture.

               The Bonds are equally and ratably secured, to the extent
          provided in the Indenture, by the pledge thereunder of the
          "Receipts and Revenues of the Authority from the Loan Agreement",
          which term is used herein as defined in the Indenture and which
          as therein defined means all moneys paid or payable to the
          Trustee for the account of the Authority by the Company in
          respect of the loan payments, including all receipts of the
          Trustee which, under the provisions of the Indenture, reduce the
          amounts of such payments. The Authority has also pledged and
          assigned to the Trustee as security for the Bonds all other
          rights and interests of the Authority under the Loan Agreement
          (other than its rights to indemnification and its administrative
          expenses and certain other rights).

               The transfer of this Bond shall be registered upon the
          registration books kept at the principal office of First Trust of
          New York, National Association, as Registrar, at the written
          request of the Registered Owner hereof or his attorney duly
          authorized in writing, upon surrender of this Bond at said
          office, together with a written instrument of transfer
          satisfactory to the Registrar duly executed by the Registered
          Owner or his duly authorized attorney.

               In the manner and with the effect provided in the Indenture,
          each of the Bonds may be redeemed prior to maturity, as follows:

                    (a) The Bonds shall be subject to redemption by the
               Authority, at the direction of the Company, on any date on
               or after September 1, 2002 in whole at any time or in part
               from time to time, at the applicable redemption price
               (expressed as a percentage of principal amount) set forth
               below, plus accrued interest to the redemption date:

                  Redemption Period                 Redemption Price
                  -----------------                 ----------------

          September 1, 2002 through August 31, 2003        102%
          September 1, 2003 through August 31, 2004        101%
          September 1, 2004 and thereafter                 100%

                    (b)  The Bonds shall be subject to redemption by the
               Authority, at the direction of the Company, in whole at any
               time at the principal amount thereof plus accrued interest
               to the redemption date, if:

                         (i) the Company shall have determined that the
                    continued operation of the Facilities is impracticable,
                    uneconomical or undesirable for any reason;

                         (ii) all or substantially all of the Facilities
                    shall have been condemned or taken by eminent domain;
                    or

                         (iii) the operation of the Facilities shall have
                    been enjoined or shall have otherwise been prohibited
                    by, or shall conflict with, any order, decree, rule or
                    regulation of any court or of any federal, state or
                    local regulatory body, administrative agency or other
                    governmental body.

                    (c)  The Bonds shall be subject to mandatory redemption
               by the Authority, at the principal amount thereof plus
               accrued interest to the redemption date, on the 180th day
               (or such earlier date as may be designated by the Company)
               after a final determination by a court of competent
               jurisdiction or an administrative agency, to the effect
               that, as a result of a failure by the Company to perform or
               observe any covenant, agreement or representation contained
               in the Loan Agreement, the interest payable on the Bonds is
               included for federal income tax purposes in the gross income
               of the owners thereof, other than any owner of a Bond who is
               a "substantial user" of the Facilities or a "related person"
               within the meaning of Section 103(b)(13) of the Internal
               Revenue Code of 1954, as amended (the "1954 Code").  No
               determination by any court or administrative agency shall be
               considered final for the purposes of this paragraph (c)
               unless the Company shall have been given timely notice of
               the proceeding which resulted in such determination and an
               opportunity to participate in such proceeding, either
               directly or through an owner of a Bond, and until the
               conclusion of any appellate review sought by any party to
               such proceeding or the expiration of the time for seeking
               such review. The Bonds shall be redeemed either in whole or
               in part in such principal amount that, in the opinion of
               Bond Counsel, the interest payable on the Bonds, including
               the Bonds remaining outstanding after such redemption, would
               not be included in the gross income of any owner thereof,
               other than an owner of a Bond who is a "substantial user" of
               the Facilities or a "related person" within the meaning of
               Section 103(b)(13) of the 1954 Code.

               If less than all of the Bonds at the time outstanding are to
          be called for redemption, the particular Bonds or portions of
          Bonds to be redeemed shall be selected by the Trustee, in such
          manner as the Trustee in its discretion may deem proper, in the
          principal amounts designated to the Trustee by the Company or
          otherwise as required by the Indenture.

               In the event any of the Bonds are called for redemption, the
          Trustee shall give notice, in the name of the Authority, of the
          redemption of such Bonds.  Such notice shall be given by mailing
          a copy of the redemption notice by first-class mail at least
          thirty (30) days prior to the date fixed for redemption to the
          Registered Owners of the Bonds to be redeemed at the addresses
          shown on the registration books; provided, however, that failure
          duly to give such notice by mailing, or any defect therein, shall
          not affect the validity of any proceedings for the redemption of
          the Bonds as to which there shall be no such failure or defect.

               With respect to any notice of redemption of Bonds in
          accordance with the redemption provisions lettered (a) or (b)
          above, unless, upon the giving of such notice, such Bonds shall
          be deemed to have been paid within the meaning of the Indenture,
          such notice shall state that such redemption, shall be
          conditional upon the receipt, by the Trustee on or prior to the
          opening of business on the date fixed for such redemption of
          moneys sufficient to pay the principal of and premium, if any,
          and interest on such Bonds to be redeemed, and that if such
          moneys shall not have been so received said notice shall be of no
          force and effect and the Authority shall not be required to
          redeem such Bonds. In the event that such notice of redemption
          contains such a condition and such moneys are not so received,
          the redemption shall not be made and the Trustee shall within a
          reasonable time thereafter give notice, in the manner in which
          the notice of redemption was given, that such moneys were not so
          received.

               If a notice of redemption shall be unconditional, or if the
          conditions of a conditional notice of redemption shall have been
          satisfied, then upon presentation and surrender of Bonds so
          called for redemption at the place or places of payment, such
          Bonds shall be redeemed.

               Any Bonds and portions of Bonds which have been duly
          selected for redemption shall cease to bear interest on the
          specified redemption date provided that moneys sufficient to pay
          the principal of, premium, if any, and interest on such Bonds
          shall be on deposit with the Trustee on the date fixed for
          redemption so that such Bonds will be deemed to be paid in
          accordance with the Indenture and such Bonds shall thereafter
          cease to be entitled to any lien, benefit or security under the
          Indenture.

               The Registered Owner of this Bond shall have no right to
          enforce the provisions of the Indenture, or to institute action
          to enforce the covenants therein, or to take any action with
          respect to any default under the Indenture, or to institute,
          appear in or defend any suit or other proceeding with respect
          thereto, except as provided in the Indenture.

               With certain exceptions as provided therein, the Indenture
          and the Loan Agreement may be modified or amended only with the
          consent of the Registered Owners of a majority in aggregate
          principal amount of all Bonds outstanding under the Indenture
          which would be adversely affected thereby.

               Reference is hereby made to the Indenture and the Loan
          Agreement, copies of which are on file with the Trustee, for the
          provisions, among others, with respect to the nature and extent
          of the rights, duties and obligations of the Authority, the
          Company, the Trustee and the Registered Owners of the Bonds.  The
          Registered Owner of this Bond, by the acceptance hereof, is
          deemed to have agreed and consented to the terms and provisions
          of the Indenture and the Loan Agreement.

               Among other things, as provided in the Indenture and subject
          to certain limitations therein set forth, this Bond or any
          portion of the principal amount hereof will be deemed to have
          been paid within the meaning and with the effect expressed in the
          Indenture, and the entire indebtedness of the Authority in
          respect thereof shall be satisfied and discharged, if there has
          been irrevocably deposited with the Trustee, in trust, money in
          an amount which will be sufficient and/or Government Obligations
          (as defined in the Indenture), the principal of and interest on
          which, when due, without regard to any reinvestment thereof, will
          provide moneys which, together with moneys deposited with or held
          by the Trustee, will be sufficient, to pay when due the principal
          of and premium, if any, and interest on this Bond or such portion
          of the principal amount hereof when due.

               Among other things, the Loan Agreement contains terms,
          provisions and conditions relating to the consolidation or merger
          of the Company with or into, and the sale, transfer or other
          disposition of assets to, another Person (as defined in the Loan
          Agreement), to the assumption by such other Person, in certain
          circumstances, of all of the obligations of the Company under the
          Loan Agreement and to the release and discharge of the Company,
          in certain circumstances, from such obligations.

               The Authority, the Trustee, the Registrar, the Paying Agent
          and any co-paying agent may deem and treat the person in whose
          name this Bond is registered as the absolute owner hereof for all
          purposes, whether or not this Bond is overdue, and neither the
          Authority, the Trustee, the Paying Agent nor any co-paying agent
          shall be affected by any notice to the contrary.

               It is hereby certified, recited and declared that all acts,
          conditions and things required by the Constitution and laws of
          the State of Arizona to exist, to have happened and to have been
          performed, precedent to and in the execution and delivery of the
          Indenture and the issuance of this Bond, do exist, have happened
          and have been performed in regular and due form as required by
          law.

               No covenant or agreement contained in this Bond or the
          Indenture shall be deemed to be a covenant or agreement of any
          official, officer, agent or employee of the Authority in his
          individual capacity, and neither the members of the Board of
          Directors of the Authority, nor any official executing this Bond,
          shall be liable personally on this Bond or be subject to any
          personal liability or accountability by reason of the issuance or
          sale of this Bond.

               This Bond shall not be entitled to any right or benefit
          under the Indenture, or be valid or become obligatory for any
          purpose, until this Bond shall have been authenticated by the
          execution by the Trustee, or its successor as Trustee, of the
          certificate of authentication inscribed hereon.


          


               IN WITNESS WHEREOF, The Industrial Development Authority of
          The County of Pima has caused this Bond to be executed with the
          manual or facsimile signature of its President or Vice President
          and a facsimile of its official seal to be imprinted hereon and
          attested with the manual or facsimile signature of its Secretary
          or Assistant Secretary.



                                   THE INDUSTRIAL DEVELOPMENT
                                   AUTHORITY OF THE COUNTY OF PIMA
          (Seal)

                                   By.............................
                                               President

          ATTEST:


          .........................
                 Secretary


          

                                                                  EXHIBIT B


                     (FORM FOR ORDINARY REGISTRATION OF TRANSFER)

                       COMPLETE AND SIGN THIS FORM FOR ORDINARY
                               REGISTRATION OF TRANSFER


          FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s) and
          transfer(s) unto


          Please Insert Social Security Or Other Identifying Number of
          Assignee
                                                                       
          ..................................................................
                                                                       
          ..................................................................

          Please print or typewrite name and address including postal zip
          code of assignee

          ..................................................................
          this bond and all rights thereunder, hereby irrevocably
          constituting and appointing ________________________ attorney to
          register such transfer on the registration books in the principal
          office of the Registrar, with full power of substitution in the
          premises.

          Dated:..............     .........................................
                                   NOTE:  The signature on this assignment
                                   must correspond with the name as written
                                   on the face of this Bond in every
                                   particular, without alteration,
                                   enlargement or any change whatsoever.


          


                                                                  EXHIBIT C

                  (FORM OF TRUSTEE'S CERTIFICATE OF AUTHENTICATION)

                            CERTIFICATE OF AUTHENTICATION

                    This is to certify that this Bond is one of the Bonds
               described in the within-mentioned Indenture.


                                FIRST TRUST OF NEW YORK, NATIONAL ASSOCIATION,
                                as Trustee


                                 By .......................................
                                              Authorized Officer



      Date of Authentication:................