Exhibit 99.1

                                   EXHIBIT A

                      SOUTHWESTERN PUBLIC SERVICE COMPANY


                               PURCHASE CONTRACT

          Southwestern Public Service Company, a New Mexico corporation (the
"Company"), confirms its agreement with each of the Purchasers (as hereinafter
defined) with respect to the sale by the Company and the purchase by the
Purchasers, severally and not jointly, of the Notes (as hereinafter defined).

          1.  Purchasers and Representative.  If there shall be two or more 
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persons, firms or corporations named as purchasers in Schedule I hereto, the
term "Purchasers" as used herein shall be deemed to mean the several persons,
firms or corporations so named (including the Representative hereinafter
mentioned, if so named, and any Purchasers substituted pursuant to paragraph 11
hereof), and the term "Representative" as used herein shall be deemed to mean
the representative or representatives named in Schedule I hereto. If there shall
be only one person, firm or corporation named in Schedule I hereto, the term
"Purchasers" and the term "Representative" as used herein shall mean such
person, firm or corporation. The Representative represents and warrants that it
has the necessary power and authority to execute this Contract on behalf of the
Purchasers and to otherwise act for each of the Purchasers in respect of all
matters referred to in this Contract. All obligations of the Purchasers
hereunder are several and not joint.

          2.  Description of Notes.  The Company proposes to issue and sell the 
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Notes as a single series under its Indenture, dated as of February 1, 1999 (the
"Original Indenture"), to The Chase Manhattan Bank, as trustee (the "Trustee"),
as it will be supplemented by a supplemental indenture creating the Notes (said
Original Indenture, as supplemented, and said supplemental indenture being
hereinafter referred to as the "Indenture" and the "Supplemental Indenture",
respectively). The Notes shall be issued in the aggregate principal amount or
amounts, shall bear interest at the rate or rates, shall be payable on the
dates, and shall mature on the date or dates set forth, and shall be subject to
optional and sinking fund redemption as described, in Schedule II hereto. The
term "Notes" as used in this Contract shall mean the notes described in this
paragraph.

 
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          3.   Representations and Warranties of the Company.  The Company 
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represents and warrants to the Purchasers that:

          (a)  The Company has filed with the Securities and Exchange Commission
     (the "Commission") a registration statement, including a prospectus, for
     the registration of securities having an aggregate principal amount not
     exceeding $220,000,000, including the Notes, under the Securities Act of
     1933, as amended (the "1933 Act"), and the offering thereof from time to
     time in accordance with Rule 415 of the rules and regulations of the
     Commission under the 1933 Act (the "1933 Act Regulations"), and has filed
     such amendments thereto as may have been required to the date hereof. Such
     registration statement has been declared effective by the Commission and
     the Indenture has been qualified under the Trust Indenture Act of 1939, as
     amended (the "1939 Act"). Such registration statement, in the form in which
     it became effective, as amended to the date hereof, including the
     information, if any, deemed to be a part thereof pursuant to Rule 430A(b)
     of the 1933 Act Regulations (the "Rule 430A Information") or Rule 434(d) of
     the 1933 Act Regulations (the "Rule 434 Information"), is hereinafter
     referred to as the "Registration Statement"; the prospectus included in the
     Registration Statement, as such prospectus may have been amended to the
     date hereof, is hereinafter referred to as the "Basic Prospectus"; and the
     Basic Prospectus, as supplemented by a prospectus supplement relating to
     the Notes (the "Prospectus Supplement"), is hereinafter referred to as the
     "Prospectus"; provided, however, that (i) the terms "Registration
     Statement", "Basic Prospectus" and "Prospectus" shall be deemed to refer to
     and include, in each case, the documents incorporated by reference therein
     pursuant to Item 12 of Form S-3 under the 1933 Act, (ii) any reference
     herein to any amendment or supplement to the Prospectus shall be deemed to
     refer to and include any documents filed after the date of the Prospectus
     pursuant to Section 13 or 14 of the Securities Exchange Act of 1934, as
     amended (the "1934 Act"), and so incorporated by reference, all of such
     documents so incorporated by reference being hereinafter referred to as the
     "Incorporated Documents", and (iii) any prospectus supplement to the Basic
     Prospectus which relates to securities other than the Notes shall not be
     deemed to be a part of the Basic Prospectus or the Prospectus. If the
     Company files a registration statement to register a portion of the Notes
     and relies on Rule 462(b) of the 1933 Act Regulations for such registration
     statement to become effective upon filing 

 
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     with the Commission (the "Rule 462 Registration Statement"), then, after
     such filing, all references to "Registration Statement" herein shall be
     deemed to be to the Registration Statement referred to above and the Rule
     462 Registration Statement, as each such registration statement may be
     amended to the date hereof. If the Company elects to rely on Rule 434 of
     the 1933 Act Regulations, all references to the "Prospectus" shall be
     deemed to include the form of prospectus and the applicable term sheet or
     abbreviated term sheet (the "Term Sheet"), as the case may be, taken
     together, provided to the Purchasers by the Company in reliance on Rule
     434.

          (b)  At the respective times the Registration Statement and any 
     post-effective amendments thereto (including the filing of the Company's
     most recent Annual Report on Form 10-K with the Commission subsequent to
     the date the Registration Statement became effective (the "Annual Report on
     Form 10-K")) became effective, the Registration Statement and any
     amendments and supplements thereto complied, and, upon the filing of the
     Prospectus Supplement with the Commission, the Prospectus will comply, with
     the provisions of the 1933 Act and the applicable 1933 Act Regulations, or
     pursuant to the 1933 Act Regulations are or will be deemed to have complied
     or to comply therewith; at the time the Registration Statement became
     effective, the Registration Statement did not contain an untrue statement
     of a material fact or omit to state a material fact required to be stated
     therein or necessary to make the statements therein not misleading; and, at
     the time the Registration Statement became effective and at the date
     hereof, the Basic Prospectus did not and does not include an untrue
     statement of a material fact or omit to state a material fact necessary in
     order to make the statements therein, in the light of the circumstances
     under which they were made, not misleading; provided, however, that none of
     the foregoing representations and warranties in this subparagraph (b) shall
     apply to that part of the Registration Statement which shall constitute the
     Statement of Eligibility under the 1939 Act of the trustee under the
     Indenture (the "Statement of Eligibility"). If Rule 434 under the 1933 Act
     Regulations is used, the Company will comply with the requirements of Rule
     434.

          (c)  The Incorporated Documents, at the time they were filed with the
     Commission, complied in all material respects with the requirements of the
     1934 Act and the rules and regulations of the Commission thereunder (the

 
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     "1934 Act Regulations"), and, when read together with the other information
     in the Prospectus, do not contain an untrue statement of a material fact or
     omit to state a material fact required to be stated therein or necessary to
     make the statements therein, in the light of the circumstances under which
     they were made, not misleading; and any additional Incorporated Documents
     will, when they are filed with the Commission, comply in all material
     respects with the requirements of the 1934 Act and the 1934 Act Regulations
     and will not contain an untrue statement of a material fact or omit to
     state a material fact required to be stated therein or necessary to make
     the statements therein, in the light of the circumstances under which they
     are made, not misleading.

          (d)  The financial statements included in the Registration Statement
     present fairly the financial position of the Company and its consolidated
     subsidiaries as at the dates indicated and the results of their operations
     for the periods specified; and, except as otherwise stated in the
     Registration Statement, such financial statements have been prepared in
     conformity with generally accepted accounting principles applied on a
     consistent basis during the periods involved and the supporting financial
     schedules included in the Registration Statement present fairly the
     information required to be stated therein. Arthur Andersen LLP, the
     accountants who certified certain of such financial statements and
     financial schedules, are independent certified public accountants as
     required by the 1933 Act and the 1933 Act Regulations.

          (e)  Except as may otherwise be reflected in or contemplated by the
     Registration Statement, since the respective dates as of which information
     is given therein (i) there has been no material adverse change nor any
     development or event involving a prospective material adverse change in the
     business, property or condition, financial or otherwise, of the Company,
     whether or not arising in the ordinary course of business, and (ii) the
     Company has not entered into any transactions which are material to the
     Company, other than in the ordinary course of business; and, except as so
     reflected or contemplated, the Company does not have any contingent
     obligations which are material to the Company.

          (f)  The Company has been duly incorporated and is validly existing as
     a corporation in good standing under the laws of the State of New Mexico
     with corporate power 

 
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     and authority to own its properties and conduct its business as described
     in the Registration Statement.

          (g)  The issuance and sale by the Company of the Notes pursuant to
     this Contract have been duly authorized by all necessary corporate action;
     and, when issued, authenticated and delivered by the Company pursuant to
     this Contract against payment of the consideration therefor specified
     herein, the Notes will be valid and binding obligations of the Company,
     enforceable in accordance with their terms, except as enforcement thereof
     may be limited by laws or principles of equity affecting generally the
     enforcement of creditors' rights, including without limitation bankruptcy
     and insolvency laws and state laws which affect the enforcement of certain
     remedial provisions of the Indenture, and will be entitled to the benefits
     of the Indenture.

          (h)  The execution and delivery of this Contract, the incurrence of
     the obligations herein set forth and the consummation of the transactions
     herein contemplated will not conflict with or constitute a breach of, or
     default under, the Restated Articles of Incorporation, as they may have
     been amended, or By-Laws of the Company or any contract, lease, note,
     mortgage or other instrument to which the Company is a party or by which it
     may be bound, or any law, administrative regulation or administrative or
     court order.

          (i)  All approvals and authorizations from the New Mexico Public
     Utility Commission which are required for the valid authorization and
     issuance of the Notes and the valid sale thereof under this Contract, have
     been obtained and are in full force and effect and the approval of no other
     governmental or regulatory authority or body is necessary in connection
     with the issuance and sale by the Company of the Notes pursuant to this
     Contract, except that there must be compliance with the securities laws in
     the jurisdictions in which the Notes are to be offered and sold.

          (j)  The franchises held by the Company, together with the applicable
     Certificates of Convenience and Necessity issued by the New Mexico Public
     Utility Commission, give the Company all necessary authority for the
     maintenance and operation of its properties and business as now conducted,
     and are free from burdensome restrictions or conditions of an unusual
     character.

 
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          (k)  Any certificate signed by any officer of the Company and
     delivered to the Representative or to Cahill Gordon & Reindel, who are
     acting as counsel for the Purchasers, shall be deemed a representation and
     warranty by the Company to each Purchaser as to the matters covered
     thereby.

          4.   Purchase and Sale.  On the basis of the representations and 
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warranties, and subject to the terms and conditions, in this Contract set forth,
the Company agrees to sell to each of the several Purchasers, severally and not
jointly, and each Purchaser agrees, severally and not jointly, to purchase from
the Company, the principal amount of the Notes set forth in Schedule I hereto
opposite the name of such Purchaser at the price specified in Schedule II
hereto.

          5.   Public Offering.  Forthwith upon the execution of this Contract, 
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the Representative shall furnish the Company in writing any information
regarding the public offering, if any, of the Notes, in addition to the
information set forth on Schedules I and II hereto, which is required to prepare
the Prospectus Supplement.

          6.   Time and Place of Closing.  Delivery of the Notes and payment 
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therefor by certified or official bank check or checks payable to the order of
the Company, or by wire transfer to a bank account specified by the Company, in
the funds specified in Schedule II hereto, shall be made at the office of
LeBoeuf, Lamb, Greene & MacRae, L.L.P., 125 West 55th Street, New York, New
York, at 10:00 A.M., New York time, on the date specified in Schedule II hereto,
or at such other place, time or date as may be agreed upon by the Company and
the Representative. The time and date of such payment and delivery are herein
called the "Closing Date".

          The Notes shall be delivered to or upon the order of the
Representative for the respective accounts of the Purchasers in registered form
in such authorized denominations and registered in such names as the
Representative may reasonably request in writing at least one business day prior
to the Closing Date or, to the extent not so requested, in the names of the
respective Purchasers in such denominations as the Company shall determine.  The
Company agrees to make the Notes available to the Representative for checking
not later than 2:30 P.M., New York time, on the last business day preceding the
Closing Date at the office of The Chase Manhattan Bank, New York, New York, or
at such other place as may be agreed upon by the Company and the Representative.

 
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          7.   Covenants of the Company.  The Company covenants with each 
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Purchaser that:

          (a)  The Company will promptly deliver to the Representative two
     signed copies of the registration statement relating to the Notes as
     originally filed and of all amendments thereto heretofore or hereafter made
     (in each case including all Incorporated Documents and exhibits thereto,
     other than exhibits incorporated by reference), and including a signed copy
     of each consent and certificate included therein or filed as an exhibit
     thereto, and will deliver to the Representative conformed copies of each of
     the foregoing (excluding such exhibits, consents and certificates) for
     distribution to the Purchasers. The Company will also deliver to the
     Purchasers, through the Representative, as soon as practicable after the
     date hereof and thereafter from time to time, as many copies of the
     Prospectus and any amendments or supplements thereto as the Representative
     may reasonably request for the purposes contemplated by the 1933 Act.

          (b)  The Company will not file any amendment to the Registration
     Statement (including any filing under Rule 462(b) of the 1933 Act
     Regulations) or make any amendment or supplement to the Prospectus
     (including any Term Sheet) of which the Representative shall not previously
     have been advised or which shall have been reasonably disapproved in
     writing by the Representative or Cahill Gordon & Reindel.

          (c)  The Company will pay or cause to be paid (i) all expenses in
     connection with (A) the preparation and filing by it of the Registration
     Statement, (B) the preparation, printing, issuance and delivery of the
     Notes as provided in paragraph 6 hereof, (C) the preparation, execution,
     filing and recording of the Indenture and the Supplemental Indenture, (D)
     the preparation of this Contract, and (E) the printing and delivery to the
     Purchasers, through the Representative, in reasonable quantities, of copies
     of the Registration Statement and the Prospectus, and any amendments or
     supplements thereto (except as otherwise provided in subparagraph (d) of
     this paragraph 7), this Contract, the Indenture and the Supplemental
     Indenture, (ii) the fees and disbursements of the Company's counsel and
     accountants related to the preparation of the Registration Statement and
     Prospectus, the issuance and sale of the Notes, (iii) the expenses incurred
     in connection with the qualification of the Notes under securities laws in
     accordance with subparagraph (g) of this paragraph 7, including 

 
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     filing fees and reasonable fees and disbursements of Cahill Gordon &
     Reindel in connection therewith and in connection with the preparation of
     the Blue Sky Survey and the Legal Investment Survey, if any, and (iv) all
     taxes, if any (except transfer taxes), on the issuance of the Notes. If
     this Contract is terminated in accordance with subparagraph (a)(i), (a)(ii)
     or (b) of paragraph 13 hereof, the Company will reimburse the Purchasers
     for all their out-of-pocket expenses, including the fee and disbursements
     of Cahill Gordon & Reindel. The Company will not in any event be liable to
     any of the Purchasers for damages on account of the loss of anticipated
     profits.

          (d)  If, at any time when a prospectus relating to the Notes is
     required to be delivered under the 1933 Act, the Prospectus, as it may then
     have been amended or supplemented, would, in the opinion of the Company or
     the Representative, include an untrue statement of a material fact or omit
     to state a material fact necessary in order to make the statements therein,
     in the light of the circumstances under which they were made, not
     misleading, or if, at such time, it shall be necessary to amend or
     supplement the Prospectus, as it may then have been amended or
     supplemented, in order to comply with Section 10 of the 1933 Act or the
     1933 Act Regulations, the Company will, subject to Section 7(b) hereof,
     forthwith prepare and file with the Commission an amendment or supplement
     which will correct such statement or omission or effect such compliance and
     will furnish a reasonable number of copies thereof to the Representative.
     During the first nine months after the date hereof, the cost of so
     preparing, filing and furnishing such amendment or supplement will be borne
     by the Company and, thereafter, by the Purchasers who request the same;
     provided, however, that should such amendment or supplement relate solely
     to the activities of any Purchaser or Purchasers, then such cost shall in
     any event be borne by such Purchasers. For purposes of this subparagraph
     (d) the Company shall be entitled to assume that a prospectus relating to
     the Notes shall no longer be required to be delivered under the 1933 Act
     from and after the forty-fifth day after the date of this Contract, unless
     it shall have received from the Representative notice to the contrary.
     Whenever a prospectus shall be so required to be delivered, the Purchasers
     will deliver the Prospectus, as it may have been amended or supplemented at
     the time of such delivery.

 
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          (e)  The Company will make generally available to its security
     holders, as soon as practicable, an earnings statement (which need not be
     audited) of the Company (and its consolidated subsidiaries, if any)
     covering a period of 12 months beginning not later than the first day of
     the Company's fiscal quarter next following the date of this Contract and
     complying with Rule 158 of the 1933 Act Regulations.

          (f)  The Company will comply with the requirements of Rule 430A of the
     1933 Act Regulations and/or Rule 434 of the 1933 Act Regulations, if and as
     applicable, and during the period when a prospectus relating to the Notes
     is required to be delivered under the 1933 Act or the 1934 Act, the Company
     will promptly advise the Representative by telephone, promptly confirmed in
     writing, (i) of the effectiveness of any post-effective amendment to the
     Registration Statement or the filing of any supplement or amendment to the
     Prospectus, (ii) of the receipt of any comments from the Commission, (iii)
     of any request by the Commission for any amendment to the Registration
     Statement or any amendment or supplement to the Prospectus or for
     additional information and (iv) of the issuance of any stop order under the
     1933 Act with respect to the Registration Statement or of the institution
     of any proceedings therefor of which the Company shall have received notice
     or become aware, and will use its best efforts to prevent the issuance of
     any such stop order and, if issued, to secure the prompt lifting or removal
     thereof. For purposes of this subparagraph (f), the Company shall be
     entitled to assume that a prospectus relating to the Notes shall no longer
     be required to be delivered under the 1933 Act from and after the forty-
     fifth day after the date of this Contract unless notified to the contrary
     by a Purchaser.

          (g)  During the period of three months from the date of this Contract,
     the Company will furnish such proper information as may lawfully be
     required and otherwise cooperate in qualifying the Notes for offer and sale
     under the securities laws of such jurisdictions as the Representative may
     reasonably designate; provided, however, that the Company shall not be
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     required to qualify as a foreign corporation or to file a general consent
     to service of process in any jurisdiction, or to comply with any other
     requirement deemed by the Company to be unduly burdensome.

          (h)  The Company, during the period when a prospectus relating to the
     Notes is required to be delivered under 

 
                                      -10-

     the 1933 Act, will (i) file promptly all documents required to be filed
     with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the
     1934 Act and (ii) promptly notify the Representative by telephone and
     confirm in writing if the rating assigned by Moody's Investors Service,
     Inc. or Standard & Poor's Ratings Group to any debt securities of the
     Company shall have been lowered or if Moody's Investors Service, Inc. or
     Standard & Poor's Ratings Group shall have informed the Company or publicly
     announced that it has under surveillance or review, with possible negative
     implications, its rating of the Notes or any other debt securities of the
     Company.

          (i)  Promptly after the execution and delivery of this Contract, the
     Company will transmit copies of the Prospectus to the Commission for filing
     pursuant to Rule 424 of the 1933 Act Regulations. If the Company elects to
     rely on Rule 434 of the 1933 Act, the Company will prepare a Term Sheet
     that complies with the requirements of Rule 434 of the 1933 Act Regulations
     and will transmit copies of the form of Prospectus complying with Rule
     434(c)(2) of the 1933 Act in accordance with Rule 424 under the 1933 Act
     Regulations.

          (j)  Between the date hereof and the date which is 10 days after the
     Closing Date, the Company will not, without the prior written consent of
     the Representative, offer or sell or enter into any agreement to sell, any
     of its other debt securities which are substantially similar to the Notes;
     it being understood that the Company may offer and sell or enter into an
     agreement to offer and sell subordinated debt securities in connection with
     an offering of trust offered preferred securities.

          8.   Conditions of Purchasers' Obligations.  The several obligations 
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of the Purchasers to purchase and pay for the Notes shall be subject to the
accuracy when made of the representations and warranties on the part of the
Company contained herein or in certificates of the Company delivered pursuant to
the provisions hereof, to the performance by the Company of its obligations to
be performed hereunder at or prior to the Closing Date and to the following
further conditions:

          (a)  No stop order suspending the effectiveness of the Registration
     Statement shall be in effect at the Closing Date, and no proceedings for
     that purpose shall then be pending before, or threatened by, the
     Commission. A prospectus containing information relating to the descrip-

 
                                      -11-

     tion of the Notes, the specific method of distribution and similar matters
     shall have been filed with the Commission in accordance with Rule
     424(b)(1), (2), (3), (4) or (5), as applicable (or any required post-
     effective amendment providing such information shall have been filed and
     declared effective in accordance with the requirements of Rule 430A), or,
     if the Company has elected to rely upon Rule 434 of the 1933 Act
     Regulations, a Term Sheet including the Rule 434 Information shall have
     been filed with the Commission in accordance with Rule 424(b)(7).

          (b)  At the Closing Date, the order of the New Mexico Public Utility
     Commission authorizing and approving the issuance and sale of the Notes
     shall be final and in full force and effect and the time for appeal
     therefrom or review thereof or intervention with respect thereto shall have
     expired.

          (c)  At the Closing Date, the Representative shall have received a
     certificate, dated the Closing Date, of the Company signed by its President
     or one of its Vice Presidents, substantially in the form thereof attached
     as Exhibit A hereto.

          (d)  At the Closing Date, the Representative shall have received
     opinions, dated the Closing Date, of LeBoeuf, Lamb, Greene & MacRae,
     L.L.P.; Hinkle, Cox, Eaton, Coffield & Hensley; Rainey, Ross, Rice & Binns;
     and Foulston & Siefkin, counsel for the Company, and Cahill Gordon &
     Reindel, counsel for the Purchasers, substantially in the forms thereof
     attached hereto as Exhibits B, C, D, E and F respectively, with reproduced
     or conformed copies thereof for each of the Purchasers.

          (e)  At the Closing Date, the Representative shall have received a
     letter, dated the Closing Date, from Arthur Andersen LLP, substantially to
     the effect set forth in Exhibit G hereto, with reproduced or conformed
     copies thereof for each of the Purchasers.

          (f)  At the Closing Date, Cahill Gordon & Reindel, counsel for the
     Purchasers, shall have been furnished with such documents and opinions as
     they may require for the purpose of enabling them to pass upon the issuance
     and sale of the Notes as herein contemplated and related proceedings, or in
     order to evidence the accuracy or completeness of any of the
     representations or warranties, or the fulfillment of any of the conditions
     herein contained; 

 
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     and all proceedings taken by the Company in connection with the issuance
     and sale of the Notes as herein contemplated shall be satisfactory in form
     and substance to the Representative and Cahill Gordon & Reindel.

          9.   Conditions of Company's Obligation.  The obligation of the 
               ----------------------------------                            
Company to deliver the Notes shall be subject to the following conditions:

          (a)  No stop order suspending the effectiveness of the Registration
     Statement shall be in effect at the Closing Date, and no proceedings for
     that purpose shall then be pending before, or threatened by, the
     Commission.

          (b)  At the Closing Date, the order of the New Mexico Public Utility
     Commission authorizing and approving the issuance and sale of the Notes
     shall be final and in full force and effect and the time for appeal
     therefrom or review thereof or intervention with respect thereto shall have
     expired.

          10.  Indemnification.  (a)  The Company agrees to indemnify and hold 
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harmless each Purchaser and each person who controls any Purchaser within the
meaning of Section 15 of the 1933 Act against any and all losses, claims,
damages or liabilities, joint or several, to which they or any of them may
become subject and to reimburse each such Purchaser and controlling person for
any legal or other expenses (including, subject to subparagraph (c) of this
paragraph 10, reasonable counsel fees) reasonably incurred by them, as incurred,
in connection with any such losses, claims, damages or liabilities or in
connection with investigating or preparing for or defending against any
litigation, or any investigation or proceeding by any governmental agency or
body, commenced or threatened, or in connection with effecting a settlement of
any such litigation, investigation or proceeding (if such settlement is effected
with the written consent of the Company), insofar as such losses, claims,
damages, liabilities, expenses, litigation, investigations or proceedings arise
out of, or are based upon, an untrue statement or alleged untrue statement of a
material fact contained in the Registration Statement, or in any amendment
thereto, or the omission or alleged omission therefrom of a material fact
required to be stated therein or necessary to make the statements therein not
misleading, or an untrue statement or alleged untrue statement of a material
fact included in the Basic Prospectus or the Prospectus, as it may have been or
be amended or supplemented, or the omission or alleged omission therefrom of a
material fact necessary in order to make the

 
                                      -13-

statements therein, in the light of the circumstances under which they were
made, not misleading; provided, however, that the indemnity agreement contained
in this subparagraph (a) shall not apply to any such losses, claims, damages,
liabilities, expenses, litigation, investigations or proceedings arising out of,
or based upon, any such untrue statement or alleged untrue statement, or any
such omission or alleged omission, if such statement or omission was made in
reliance upon and in conformity with information furnished in writing to the
Company on behalf of any Purchaser, through the Representative, expressly for
use in the Prospectus, or any amendment or supplement thereto, or arising out
of, or based upon, any such untrue statement or alleged untrue statement in, or
any such omission or alleged omission from, the Statement of Eligibility; and
provided, further, that the indemnity agreement contained in this subparagraph
(a) shall not inure to the benefit of any Purchaser or of any person controlling
such Purchaser on account of any such loss, claim, damage, liability, expense,
litigation, investigation or proceeding arising from the sale of Notes to any
person if (i) such Purchaser shall have failed to send or give to such person
(A) with or prior to the written confirmation of such sale, a copy of the
Prospectus together with any amendments or supplements thereto which shall
theretofore have been furnished to such Purchaser, or (B) with or prior to the
delivery of such Notes to such person, a copy of any amendment or supplement to
the Prospectus which shall have been furnished to such Purchaser subsequent to
such written confirmation and prior to the delivery of such Notes to such
person, and (ii) in either such case, any untrue or misleading statement or
omission made or alleged to have been made shall have been eliminated or
remedied in the Prospectus or the amendment or supplement thereto which such
Purchaser so failed to send or give to such person and such Purchaser would not
have been liable had a copy of such Prospectus, amendment or supplement, as the
case may be, been so sent or given to such person. Each Purchaser agrees
promptly to notify the Company and each other Purchaser of the commencement of
any litigation, investigation or proceeding against it or any such controlling
person in connection with the issuance and sale of the Notes.
 
          (b)  Each Purchaser agrees to indemnify and hold harmless the Company,
its directors and officers, and each person who controls the Company within the
meaning of Section 15 of the 1933 Act against any and all losses, claims,
damages or liabilities, joint or several, to which they or any of them may
become subject and to reimburse each of them for any legal or other expenses
(including, subject to subparagraph (c) of this paragraph 10, reasonable counsel
fees) incurred by them, as in-

 
                                      -14-

     curred, in connection with any such losses, claims, damages or liabilities
     or in connection with investigating or preparing for or defending against
     any litigation, or any investigation or proceeding by any governmental
     agency or body, commenced or threatened, or in connection with effecting a
     settlement of any such litigation, investigation or proceeding (if such
     settlement is effected with the written consent of each Purchaser affected
     thereby), insofar as such losses, claims, damages, liabilities, expenses,
     litigations, investigations or proceedings arise out of, or are based upon,
     an untrue statement or alleged untrue statement of a material fact
     contained in the Registration Statement, or in any amendment thereto, or
     the omission or alleged omission therefrom of a material fact required to
     be stated therein or necessary to make the statements therein not
     misleading, or an untrue statement or alleged untrue statement of a
     material fact included in the Prospectus, or any amendment or supplement
     thereto, or the omission or alleged omission therefrom of a material fact
     necessary in order to make the statements therein, in the light of the
     circumstances under which they were made, not misleading, if such statement
     or omission was made in reliance upon and in conformity with information
     furnished in writing to the Company on behalf of such Purchaser, through
     the Representative, expressly for use in the Registration Statement (or any
     amendment thereto) or the Prospectus, or any amendment or supplement
     thereto. The Company agrees promptly to notify the Representative of the
     commencement of any litigation, investigation or proceeding against it, any
     such director or officer, or any such controlling person, in connection
     with the issuance and sale of the Notes.

          (c)  The Company and the several Purchasers each agree that, upon
     receipt of notice of the commencement of any action against it or any
     director, officer or person controlling the Company or any person
     controlling such Purchaser as aforesaid, in respect of which indemnity may
     be sought on account of any indemnity agreement contained herein, it will
     promptly give notice of the commencement thereof to the party or parties
     against whom indemnity shall be sought hereunder, but the omission so to
     notify such indemnifying party or parties of any such action shall not
     relieve such indemnifying party or parties from any liability which it or
     they may have to the indemnified party otherwise than on account of such
     indemnity agreement. In case such notice of any such action shall be so
     given, such indemnifying party shall be entitled to participate at its own
     expense in the defense, or, if it so elects, to assume (in conjunction with
     any other indemnifying parties) the defense, of such action, in which event
     such defense shall be conducted by counsel chosen by such indemnifying

 
                                      -15-

     party or parties and satisfactory to the indemnified party or parties who
     shall be defendant or defendants in such action. Such indemnified party
     shall have the right to employ its own counsel in any such case, but the
     fees and expenses of such counsel shall be at the expense of such
     indemnified party unless the employment of such counsel shall have been
     authorized in writing by the indemnifying party in connection with the
     defense of such action or the indemnifying party shall not have employed
     counsel satisfactory to the indemnified party to have charge of such
     defense within a reasonable time after notice by the indemnified party or
     such indemnified party shall have reasonably concluded that there may be
     defenses available to it which are different from or additional to those
     available to the indemnifying party (in which case the indemnifying party
     shall not have the right to direct the defense of such action on behalf of
     the indemnified party). In no event shall the indemnifying parties be
     liable for fees and expenses of more than one counsel (in addition to one
     local counsel) separate from their own counsel for all indemnified parties
     in connection with any one action or separate but similar or related
     actions in the same jurisdiction arising out of the same general
     allegations or circumstances. The indemnity agreements contained in this
     paragraph 10 shall be in addition to any liability which the Company or the
     Purchasers may otherwise have.

          11.  Contribution.  If the indemnification provided for in paragraph 
               ------------                                      
10 hereof is for any reason unavailable to or insufficient to hold harmless an
indemnified party in respect of any losses, claims, damages or liabilities
referred to therein; then each indemnifying party shall contribute to the
damages and expenses incurred by such indemnified party, as incurred, (i) in
such proportions as is appropriate to reflect the relative benefits received by
the Company on the one hand and the Purchasers on the other hand from the
offering of the Notes pursuant to this Contract or (ii) if the allocation
provided by clause (i) is not permitted by applicable law, in such proportion as
is appropriate to reflect not only the relative benefits referred to in clause
(i) above but also the relative fault of the Company on the one hand and of the
Purchasers on the other hand in connection with the statements or omissions,
which resulted in such losses, claims, damages or liabilities, as well as any
other relevant equitable considerations.

          The relative benefits received by the Company on the one hand and the
Purchasers on the other hand in connection with the offering of the Notes
pursuant to this Contract shall be deemed to be in the same respective
proportions as the total net proceeds from the offering of the Notes pursuant to
this 

 
                                      -16-

Contract (before deducting expenses) received by the Company and the total
underwriting discount received by Purchasers, in each case as set forth on the
cover of the Prospectus, bear to the aggregate initial public offering price of
the Notes as set forth on such cover.

          The relative fault of the Company on the one hand and the Purchasers
on the other hand shall be determined by reference to, among other things,
whether any such untrue or alleged untrue statement of a material fact or
omission or alleged omission to state a material fact relates to information
supplied by Purchasers or by the Company and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission.

          The Company and the Purchasers agree that it would not be just and
equitable if contribution pursuant to this paragraph 11 were determined by pro
rata allocation (even if the Purchasers were treated as one entity for such
purpose) or by any other method of allocation which does not take account of the
equitable considerations referred to above in this Section 11.  The aggregate
amount of losses, claims, damages and liabilities incurred by an indemnified
party and referred to above in this paragraph 11 shall be deemed to include any
legal or other expenses (including, subject to subparagraph (c) of paragraph 10,
reasonable counsel fees) reasonably incurred by such indemnified party in
investigating, preparing or defending against any litigation, or any
investigation or proceeding by any governmental agency or body, commenced or
threatened, or any claim whatsoever based upon any such untrue or alleged untrue
statement or omission or alleged omission.

          Notwithstanding the provisions of this paragraph 11, no Purchaser
shall be required to contribute any amount in excess of the amount by which the
total price at which the Notes underwritten by it and distributed to the public
were offered to the public exceeds the amount of any damages which such
Purchaser has otherwise been required to pay by reason of any such untrue or
alleged untrue statement or omission or alleged omission.

          No person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the 1933 Act) shall be entitled to contribution from any
person who was not guilty of such fraudulent misrepresentation.

          For purposes of this paragraph 11, each person, if any, who controls a
Purchaser within the meaning of Section 15 

 
                                      -17-

of the 1933 Act or Section 20 of the 1934 Act shall have the same rights to
contribution as such Purchaser, and each director of the Company and each
officer of the Company, and each person, if any, who controls the Company within
the meaning of paragraph 15 of the 1933 Act or Section 20 of the 1934 Act shall
have the same rights to contribution as the Company. The Purchaser's respective
obligations to contribute pursuant to this paragraph 11 are several in
proportion to the number of Notes set forth opposite their respective names in
Schedule 1 hereto and not joint.

          12.  Substitution of Purchasers. If any Purchaser or Purchasers shall
               --------------------------     
fail or refuse at the Closing Date (otherwise than for some reason sufficient to
justify, in accordance with the provisions hereof, the cancellation or
termination of its or their obligations hereunder) to purchase and pay for the
Notes which it or they have agreed to purchase as provided in paragraph 4 hereof
(the "Defaulted Notes"), and:

          (a)  if the aggregate principal amount of the Defaulted Notes does not
     exceed 10% of the aggregate principal amount of the Notes, the remaining
     Purchasers (the "Non-Defaulting Purchasers") shall have the right, within a
     period of 24 hours thereafter, to make arrangements for one or more of the
     Non-Defaulting Purchasers, or any other purchasers acceptable to the
     Company, to purchase all, but not less than all, of the Defaulted Notes in
     such principal amounts as may be agreed upon and upon the terms herein set
     forth; if, however, during such 24 hour period the Non-Defaulting
     Purchasers shall not have completed such arrangements for the purchase of
     all the Defaulted Notes, then the Non-Defaulting Purchasers shall be
     obligated to purchase and pay for the Defaulted Notes in proportion to
     their respective original purchase commitments hereunder (based upon the
     ratio that each of their respective original purchase commitments bears to
     the aggregate original purchase commitment of the Non-Defaulting
     Purchasers); or

          (b)  if the aggregate principal amount of the Defaulted Notes exceeds
     10% of the aggregate principal amount of the Notes, the Non-Defaulting
     Purchasers shall have the right, within a period of 24 hours thereafter, to
     make arrangements for one or more of the Non-Defaulting Purchasers, or any
     other purchasers acceptable to the Company, to purchase the Defaulted Notes
     in such principal amounts as may be agreed upon and upon the terms herein
     set forth; if, however, during such 24 hour period the

 
                                      -18-

     Non-Defaulting Purchasers shall not have completed such arrangements for
     the purchase of all the Defaulted Notes, then the Company may, within a
     further period of 24 hours, make arrangements with one or more other
     members of the National Association of Securities Dealers, Inc.,
     satisfactory to the Non-Defaulting Purchasers, to purchase and pay for,
     upon the terms herein set forth, Defaulted Notes for the purchase of which
     no arrangements shall have been made by the Non-Defaulting Purchasers. In
     the event that neither the Non-Defaulting Purchasers nor the Company has
     arranged for the purchase of the Defaulted Notes as above provided, then
     this Contract shall terminate.

          In the event that the sale and delivery of all or any principal amount
of the Notes shall be effected as provided in clause (a) or (b) above, (a)
either the Company or the Representative shall have the right to postpone the
Closing Date until the fifth business day after the Closing Date originally
specified in paragraph 6 hereof or such other time as the Company and the
Representative (or the representative of the Non-Defaulting Purchasers and the
substituted purchasers, if any, if the Representative shall be in default) shall
agree, (b) the Company shall promptly prepare and file with the Commission any
amendments or supplements to the Prospectus which may thereby be made necessary
and (c) the respective principal amounts of Notes to be purchased by the Non-
Defaulting Purchasers or substituted purchasers shall be taken as the basis of
their respective purchase commitments hereunder.

          In the event that this Contract shall terminate as provided in clause
(b) above, neither the Company nor the Non-Defaulting Purchasers shall be under
any obligation under this Contract except as otherwise provided in subparagraph
(c) of paragraph 7 hereof

          No action taken by the Company or the Non-Defaulting Purchasers under
this paragraph 12 shall relieve any defaulting Purchaser of liability in respect
of its default hereunder.

          13.  Termination. (a) This Contract may be terminated at any time at
               ----------- 
or prior to the Closing Date by the Representative if:
 
               (i)  (A) the Company shall have failed or refused to perform any
     covenant or agreement on its part to be performed hereunder at or prior to
     the Closing Date, or (B) the conditions specified in paragraph 8 hereof
     shall not have been fulfilled;

 
                                      -19-

               (ii)  subsequent to the respective dates as of which information
     is given in the Prospectus in the form first filed pursuant to Rule 424(b),
     other than as set forth or contemplated therein at such time, or subsequent
     to the date hereof there shall have been any material adverse change in the
     business, property or condition, financial or otherwise, of the Company,
     whether or not arising in the ordinary course of business, the effect of
     which is, in the reasonable judgment of the Representative, so material and
     adverse as to make it impracticable or inadvisable for the Purchasers to
     market the Notes, or to enforce contracts for the sale of the Notes, upon
     the terms specified in the Prospectus;

               (iii) (A) there shall have occurred any outbreak of hostilities
     or material escalation thereof or other national or international calamity
     or crisis, (B) trading generally on the New York Stock Exchange shall have
     been suspended (other than a temporary suspension to provide for an orderly
     market), or minimum or maximum prices for trading shall have been fixed, or
     maximum ranges for prices for securities shall have been required on said
     exchange or by order of the Commission or any other governmental authority
     having jurisdiction, or (C) a banking moratorium shall have been declared
     by either Federal or New York State authorities, in any such case with the
     result that, in the reasonable judgment of the Representative, it shall be
     impracticable for the Purchasers to market the Notes, or to enforce
     contracts for the sale of the Notes, upon the terms specified in the
     Prospectus; or

               (iv)  the rating assigned by Moody's Investors Service, Inc. or
     Standard & Poor's Ratings Group to any debt securities of the Company as of
     the date of this Contract shall have been lowered since such date or
     Moody's Investors Service, Inc. or Standard & Poor's Ratings Group shall
     have informed the Company or publicly announced that it has under
     surveillance or review, with possible negative implications, its rating of
     the Notes or any other debt securities of the Company.

               (b)   This Contract may be terminated at any time at or prior to
the Closing Date by the Company if the conditions specified in paragraph 9
hereof shall not have been fulfilled.

               (c)   This Contract may be terminated by the Company as provided
in paragraph 12 hereof.

 
                                      -20-

               (d)  Termination of this Contract under this paragraph 13 shall
be effected by giving notice thereof to the Company or the Representative, as
the case may be.

               (e)  Any termination of this Contract pursuant to this paragraph
13 shall be without liability of any party to any other party except as
otherwise provided in subparagraph (c) of paragraph 7 hereof and provided
further that paragraphs 10 and 11 shall survive such termination and remain in
full force and effect.

               14.  Survival. The respective representations, warranties and
                    -------- 
agreements of the Company and the Purchasers contained in this Contract or
contained in certificates of officers of the Company submitted in conjunction
herewith will remain operative and in full force and effect, regardless of any
investigation made by or on behalf of the Company, any of its directors and
officers or any controlling person thereof, or any Purchaser or any controlling
person thereof, and shall survive the delivery of the Notes.

               15.  Miscellaneous. This Contract shall inure to the benefit of
                    -------------
the Company, the Purchasers and, with respect to the provisions of paragraphs 10
and 11 hereof, each director, officer and controlling person referred to in said
paragraphs 10 and 11, and their respective successors. Nothing in this Contract
is intended or shall be construed to give to any other person, firm or
corporation any legal or equitable right, remedy or claim under or in respect of
this Contract or any provision herein contained. The term "successors" as used
in this Contract shall not include any purchaser of any of the Notes merely
because of such purchase. The validity and interpretation of this Contract shall
be governed by the laws of the State of New York. This Contract may be executed
in one or more counterparts, and if executed in more than one counterpart the
executed counterparts shall constitute a single instrument.

               16.  Notices. Except as herein otherwise specifically provided,
                    -------  
all notices and other communications hereunder shall be in writing and if sent
to the Purchasers shall be mailed, delivered or telecopied and confirmed in
writing to the Representative at the address and telecopy number set forth in
Schedule I hereto or, if sent to the Company, shall be mailed, delivered or
telecopied (303-294-2583) and confirmed in writing to it at 1225 17th Street,
Denver, CO 80202, Attention: Senior Vice President and Chief Financial Officer,
with a copy to (212-424-8500) and confirmed in writing to LeBoeuf, Lamb,

 
                                      -21-

Greene & MacRae, L.L.P., 125 West 55th Street, New York, NY 10019, Attention:
Susan A. Marshall.

 
                                      -22-

          The Company and the Representative, on behalf of the Purchasers, have
caused this Purchase Contract to be executed and delivered this 25th day of
February, 1999.

                         SOUTHWESTERN PUBLIC SERVICE COMPANY

                         By:   /s/ Brian P. Jackson
                               --------------------
                               Name:   Brian P. Jackson
                               Title:  Senior Vice President,
                               Chief Financial Officer and
                               Treasurer

 

                         SALOMON SMITH BARNEY INC.
                         As Representative of the Purchasers
                         listed in Schedule I hereto

                         By:   /s/ Paul T. Addison
                               -------------------
                               Name:  Paul T. Addison
                               Title: Managing Director

 
                                                                      SCHEDULE I
                                                                      ----------

                                  PURCHASERS


                                                    PRINCIPAL AMOUNT OF
                                                          NOTES
 
PURCHASER
- ---------

Salomon Smith Barney Inc.                               $ 60,000,000
Chase Securities Inc.                                     20,000,000
NationsBanc Montgomery Securities LLC                     20,000,000
                                                        ------------
Total                                                   $100,000,000
                                                        ============



                                REPRESENTATIVE



Name:                   Salomon Smith Barney Inc.
Address:                388 Greenwich Street
                        New York, New York  10013
Attention:              Peter Kind
Telecopy No.:           212-816-0901

 
                                                                     SCHEDULE II
                                                                     -----------

                        INFORMATION REGARDING THE BONDS
                             AND THE SALE THEREOF


 .    REGISTRATION STATEMENT NO.:  333-05199

 .    AGGREGATE PRINCIPAL AMOUNT(S), MATURITY DATE(S) AND
     INTEREST RATE(S):
 
 
 
============================================================================================================================
                 PRINCIPAL                        MATURITY                                INTEREST
                  AMOUNT                            DATE                                    RATE
- ----------------------------------------------------------------------------------------------------------------------------
                                                                                    
                $100,000,000                      March 1, 2009                             6.20%
============================================================================================================================
 

 .    INTEREST PAYMENT DATES:  March 1 and September 1

 .    RECORD DATES:  February 15 and August 15

 .    INTEREST TO ACCRUE FROM:  March 2, 1999

 .    PRICE TO BE PAID TO COMPANY: 99.196% of the principal amount, plus accrued
     interest, if any, from March 2, 1999 to the date of payment by, and
     delivery to, the Purchasers.
 .
     METHOD OF AND SPECIFIED FUNDS FOR PAYMENT OF PURCHASE PRICE: Wire transfer
     of immediately available funds.

 .    INITIAL PUBLIC OFFERING PRICE (IF ANY): 99.846% of the principal amount,
     plus accrued interest, if any, from March 2, 1999 to the date of payment
     by, and delivery to, the ultimate purchaser.

 .    CLOSING DATE:  March 2, 1999

 .    OPTIONAL REDEMPTION: The Notes will be redeemable at the option of the
     Company at any time at a redemption price equal to the greater of (i) 100%
     of the principal amount of the notes to be redeemed or (ii) the sum of the
     present values of the remaining scheduled payments of principal and
     interest thereof discounted to the redemption date on a semi-annual basis
     (assuming a 360-day year consisting of twelve 30-day months) at the
     Treasury Yield (as defined), plus 0.15%, plus, in each case, accrued and
     unpaid interest to the redemption date.

 
 .    SINKING FUND:  None.

 .    BASIC PROSPECTUS: The Basic Prospectus referred to in the Note Purchase
     Contract shall mean and refer to the Basic Prospectus dated July 11, 1996.

 
                                                                       Exhibit A
                                                                              to
                                                          Note Purchase Contract
                                                          ----------------------

                      SOUTHWESTERN PUBLIC SERVICE COMPANY

                                  CERTIFICATE

          Pursuant to paragraph 8(c) of the Purchase Contract, dated February
25, 1999 (the "Contract"), between Southwestern Public Service Company, a New
Mexico corporation (the "Company"), and the several Purchasers named in Schedule
I thereto, the Company DOES HEREBY CERTIFY that:

          (a)  No stop order suspending the effectiveness of the Registration
     Statement is in effect and no proceedings for that purpose are pending
     before or, to the knowledge of the Company, threatened by the Commission.

          (b)  The order of the New Mexico Public Utility Commission authorizing
     and approving the issuance and sale of the Notes is final and in full force
     and effect and the time for appeal therefrom or review thereof or
     intervention with respect thereto has expired.

          (c)  At the date hereof, the Prospectus, as it may have been amended
     or supplemented, complies with the provisions of the 1933 Act and the 1933
     Act Regulations, or pursuant to the 1933 Act Regulations is deemed to
     comply therewith; and, at the date of the Contract, the Prospectus did not,
     and, at the date hereof, the Prospectus, as it may have been amended or
     supplemented, does not, include an untrue statement of a material fact or
     omit to state a material fact necessary in order to make the statements
     therein, in the light of the circumstances under which they were made, not
     misleading; provided, however, that none of the foregoing certifications in
     this paragraph (c) shall apply to statements in or omissions from the
     Prospectus, as it may have been amended or supplemented, made in reliance
     upon and in conformity with information furnished in writing to the Company
     by or on behalf of any Purchaser, through the Representative, expressly for
     use in the Prospectus or any amendment or supplement thereto. The Company
     has delivered to the Representative copies of the Prospectus and all
     amendments and supplements thereto.

                                      A-1

 
          (d)  The financial statements incorporated by reference in the
     Prospectus, as it may have been amended or supplemented, present fairly the
     financial position of the Company as at the dates indicated and the results
     of their operations for the periods specified; and, except as otherwise
     stated in the Prospectus, as it may have been amended or supplemented, such
     financial statements have been prepared in conformity with generally
     accepted accounting principles applied on a consistent basis during the
     periods involved. Arthur Andersen LLP, the accountants who certified
     certain of such financial statements, are independent certified public
     accountants as required by the 1933 Act and the 1933 Act Regulations.

          (e)  Except as may otherwise be reflected in or contemplated by the
     Prospectus, as it may have been amended or supplemented, since the
     respective dates as of which information is given therein, (i) there has
     been no material adverse change or any development or event involving a
     prospective material adverse change in the business, property or condition,
     financial or otherwise, of the Company, whether or not arising in the
     ordinary course of business and (ii) the Company has not entered into any
     transactions which are material to the Company, other than in the ordinary
     course of business; and, except as so reflected or contemplated, the
     Company does not have any contingent obligations which are material to the
     Company.

          (f)  The Company has been duly incorporated and is validly existing as
     a corporation in good standing under the laws of the State of New Mexico
     with corporate power and authority to own its properties and conduct its
     business as described in the Prospectus, as it may have been amended or
     supplemented.

          (g)  The representations and warranties of the Company contained in
     subparagraphs (g), (h), (i), and (j) of paragraph 3 of the Contract are
     true and correct as of the date hereof.

          All terms contained in this Certificate which are defined in the
Contract are used herein with the same meaning as in the Contract.

                                      A-2

 
          IN WITNESS WHEREOF, the Company has caused this Certificate to be
executed on its behalf this 2nd day of March 1999.

                         SOUTHWESTERN PUBLIC SERVICE COMPANY

                         By: _____________________________________
                             Name:
                             Title:

                                      A-3

 
                                                                       Exhibit B
                                                                              to
                                                          Note Purchase Contract
                                                          ----------------------

            [LETTERHEAD OF LEBOEUF, LAMB, GREENE & MACRAE, L.L.P.]


[Purchasers]


Ladies and Gentlemen:

          We have acted as counsel to Southwestern Public Service Company (the
"Company") in connection with the sale by the Company of $100,000,000 aggregate
principal amount of its Senior Notes (the "Notes"), which are registered
pursuant to the registration statement (File No. 333-05199) of the Company for
the registration under the Securities Act of 1933, as amended (the "1933 Act"),
of up to $220,000,000 aggregate principal amount of securities, including the
Notes.  This opinion is being delivered to you pursuant to Section 8(d) of the
Purchase Contract, dated February 25, 1999 (the "Purchase Contract"), between
the Company and the several purchasers named therein (the "Purchasers").  Unless
otherwise stated, defined terms used herein shall have the respective meanings
given them in the Purchase Contract.

          We are not general counsel to the Company and our representation of
the Company consists of advising it with respect to corporate and regulatory
matters as to which we have been specifically consulted.  We are familiar with
the legal matters pertaining to, and the corporate proceedings of the Company
taken with respect to, the authorization, issuance and sale by the Company of
the Notes.  We have examined, among other things, the Registration Statement and
the Prospectus, and any amendment or supplement thereto, the corporate records
of the Company, the Indenture, the Supplemental Indenture creating the Notes,
and such other proceedings, papers and documents as we have deemed relevant for
the purpose of rendering the opinions enumerated below.  In such examination, we
have assumed the genuineness of all signatures, the authenticity of all
documents submitted to us as originals, the conformity to the original documents
of all documents submitted to us as copies and the authenticity of all such
latter documents.  We have relied as to various questions of fact (but not as to
legal conclusions) upon discussions with officers and representatives of the
Company and the representations and warranties of the 

                                      B-1

 
Company contained in the Purchase Contract and upon the certificates of public
officials and of officers of the Company being delivered to you thereunder.

          On the basis of the foregoing, and subject to the limitations and
qualifications set forth herein, it is our opinion that:

          (i)   The Indenture has been duly and validly authorized, executed and
     delivered by the Company and is in due and proper form and (assuming the
     Indenture has been duly authorized, executed and delivered by the Trustee)
     constitutes a legal, valid and binding obligation of the Company,
     enforceable in accordance with its terms, except as enforcement thereof may
     be limited by laws and principles of equity affecting generally the
     enforcement of mortgagees' and other creditors' rights, including without
     limitation bankruptcy and insolvency laws and state laws which affect the
     enforcement of certain remedial provisions of the Indenture; provided,
     however, that such state laws will not, in our opinion, render the remedies
     afforded by the Indenture inadequate for the practical realization of the
     benefit of the security provided thereby.

          (ii)  The Notes are in due and proper form and the issuance and sale
     of the Notes have been duly authorized by all necessary corporate action,
     and when duly executed, authenticated and delivered to the Purchasers
     pursuant to the Purchase Contract against payment of the consideration set
     forth therein, the Notes will be legal, valid and binding obligations of
     the Company enforceable (subject to the exceptions and limitations referred
     to in paragraph (i) hereof) in accordance with their terms.

          (iii) The Indenture is qualified under the Trust Indenture Act of
     1939, as amended.

          (iv)  The Purchase Contract has been duly authorized, executed and
     delivered by the Company.

          (v)   We are not aware of any approval, authorization, consent or
     other order of any federal regulatory board or body, including under the
     Public Utility Holding Company Act of 1935, as amended, which is legally
     required (other than in connection or compliance with the provisions of the
     securities laws of any jurisdiction) for the issuance and sale by the
     Company of the Notes pursuant to the Purchase Contract.

          (vi)  The Notes and the Indenture conform as to legal matters to the
     description of the terms thereof contained

                                      B-2

 
     in the Registration Statement and the Prospectus, as amended or
     supplemented to the date hereof.

          (vii) The Registration Statement is effective under the 1933 Act and,
     to the best of our knowledge, no proceedings for a stop order have been
     instituted or are pending or threatened under Section 8(d) of the 1933 Act;
     and, at the time the Registration Statement became effective and at the
     date of the Purchase Contract, the Registration Statement complied, and, at
     the date hereof, the Prospectus, as it may have been amended or
     supplemented, complies, as to form in all material respects with the
     requirements of the 1933 Act and the applicable instructions, rules and
     regulations thereunder, or pursuant to said instructions, rules and
     regulations are deemed to have complied or to comply therewith, although we
     do not express any opinion as to the financial statements (including the
     notes thereto) or other financial or statistical data included or
     incorporated by reference therein.

          We do not know of any legal or governmental proceeding (pending or
threatened) required to be described in the Registration Statement or the
Prospectus, as amended or supplemented to the date hereof, which is not
described as required, nor of any contract or document of a character required
to be described in the Registration Statement or the Prospectus, as amended or
supplemented to the date hereof, or to be filed as an exhibit to the
Registration Statement which is not described or filed as required.

          In connection with this opinion, we have participated in discussions
with officers and representatives of the Company, in certain of which your
representatives and counsel also participated and at which the affairs of the
Company and the contents of the Registration Statement and the Prospectus were
discussed.  There is no assurance that all possible material facts as to the
Company were disclosed to us or that our familiarity with the Company or the
operations in which it is engaged is such that we have necessarily recognized
the materiality of such facts as were disclosed, and we have to a large extent
relied upon statements of officers and representatives of the Company as to the
materiality of those facts disclosed to us.  We are not passing upon and do not
assume any responsibility for the accuracy, completeness or fairness of the
statements contained in the Registration Statement and the Prospectus.  Subject
to the foregoing, and to the other limitations and qualifications expressed in
this letter, we may state that nothing has come to our attention that would lead
us to believe that the Registration Statement, when it became effective, or at
the date of the Purchase Contract, contained an untrue statement of a material
fact or omitted to state a material 

                                      B-3

 
fact required to be stated therein or necessary to make the statements therein
not misleading, or that, at the date the Prospectus Supplement was filed with
the Securities and Exchange Commission, the Prospectus included, or, at the date
hereof, the Prospectus, as it may have been amended or supplemented, includes an
untrue statement of a material fact or omitted, or omits, to state a material
fact necessary in order to make the statements therein, in the light of the
circumstances under which they were made, not misleading; provided, that we do
not express any belief as to the financial statements (including the notes
thereto) or other financial or statistical data contained or incorporated by
reference in the Registration Statement or the Prospectus, or any amendment or
supplement thereto, as to any information contained therein furnished to the
Company in writing by any Purchaser expressly for use therein or as to the
Statement of Eligibility.

          This opinion is limited to the laws of the State of New York and the
federal law of the United States of America.  In addition, we are not opining
herein with respect to the securities or "blue sky" laws of any state.  We have
relied, with your consent, as to all matters governed by the laws of the States
of New Mexico and Texas, upon the opinion of Hinkle, Cox, Eaton, Coffield &
Hensley LLP, as to all matters governed by the laws of the States of Oklahoma,
upon the opinion of Rainey, Ross, Rice & Binns, and as to all matters governed
by the laws of the State of Kansas, upon the opinion of Foulston & Siefkin.
Finally, this opinion speaks as of the date hereof and we undertake no
responsibility to advise you of any change in circumstances after the date
hereof.
                    
          The Chase Manhattan Bank, is hereby authorized to rely upon this
letter as if this letter were addressed to it.  This letter is not being
delivered for the benefit of, nor may it be relied upon by, the holders of the
Notes or any other party to which it is not specifically addressed or to which
reliance has not expressly been permitted hereby.

                                    Very truly yours,

                                      B-4

 
                                                                       Exhibit C
                                                                              to
                                                          Note Purchase Contract
                                                          ----------------------

          [LETTERHEAD OF HINKLE, COX, EATON, COFFIELD & HENSLEY LLP]

[Purchasers]



Ladies and Gentlemen:


          This opinion is being furnished to you in connection with the sale by
Southwestern Public Service Company (the "Company") of $100,000,000 aggregate
principal amount of [Senior] Notes of the Company (the "Notes"), which are
registered pursuant to the registration statement (File No. 333-05199) of the
Company for the registration under the Securities Act of 1933, as amended (the
"1933 Act"), of up to $220,000,000 aggregate principal amount of securities,
including the Notes. This opinion is being delivered to you pursuant to Section
8(d) of the Purchase Contract, dated February 25, 1999 (the "Purchase
Contract"), between the Company and the several purchasers named therein (the
"Purchasers"). Unless otherwise stated, defined terms used herein shall have the
respective meanings given them in the Purchase Contract.

          We are familiar with the legal matters pertaining to, and the
corporate proceedings of the Company taken with respect to, the authorization,
issuance and sale by the Company of the Notes. We have examined, among other
things, the Registration Statement and the Prospectus, and any amendment or
supplement thereto, the corporate records of the Company, the Indenture, the
Supplemental Indenture creating the Notes, the proceedings before The Public
Utility Commission of the State of New Mexico with respect to the issuance and
sale of the Notes and such other proceedings, papers and documents as we have
deemed relevant for the purpose of rendering the opinions enumerated below. In
such examination, we have assumed the genuineness of all signatures, the
authenticity of all documents submitted to us as originals, the conformity to
the original documents of all documents submitted to us as copies and the
authenticity of all such latter documents. We have relied as to various
questions of fact (but not as to legal conclusions) upon discussions with
officers and representatives of the Company and the

                                      C-1

 
representations and warranties of the Company contained in the Purchase Contract
and upon the certificates of public officials and of officers of the Company
being delivered to you thereunder. With respect to the opinions expressed in
paragraph (vi) below, we have relied on information obtained from public records
and from the Company.

          On the basis of the foregoing, and subject to the limitations and
qualifications set forth herein, it is our opinion that:

          (i)   The Company has been duly incorporated and is validly existing
     as a corporation in good standing under the laws of the State of New Mexico
     with corporate power and authority to own its properties and conduct its
     business as described in the Prospectus, as amended or supplemented to the
     date hereof. To the best of our knowledge, the Company is duly qualified as
     a foreign corporation to transact business and is in good standing in each
     jurisdiction in which such qualification is required, except where the
     failure to so qualify or be in good standing would not have a material
     adverse effect on the business, properties or operations of the Company.

          (ii)  The Indenture has been duly and validly authorized, executed and
     delivered by the Company and is in due and proper form and (assuming the
     Indenture has been duly authorized, executed and delivered by the Trustee)
     constitutes a legal, valid and binding obligation of the Company,
     enforceable in accordance with its terms, except as enforcement thereof may
     be limited by laws and principles of equity affecting generally the
     enforcement of creditors' rights, including without limitation bankruptcy
     and insolvency laws and state laws which affect the enforcement of certain
     remedial provisions of the Indenture; provided, however, that such state
     laws will not, in our opinion, render the remedies afforded by the
     Indenture inadequate for the practical realization of the benefit provided
     thereby.

          (iii) The Notes are in due and proper form and the issuance and sale
of the Notes have been duly authorized by all necessary corporate action, and
when duly executed, authenticated and delivered to the Purchasers pursuant to
the Purchase Contract against payment of the consideration set forth therein,
the Notes will be legal, valid and binding obligations of the Company
enforceable (subject to the exceptions and limitations referred to in paragraph
(ii) hereof) in accordance with their terms.

                                      C-2

 
          (iv)   All approvals and authorizations of the New Mexico Public
     Utility Commission, which are required for the valid authorization and
     issuance and the valid sale of the Notes under the Purchase Contract, have
     been obtained and are in full force and effect, and the approval of no
     other governmental regulatory body (including the State Corporation
     Commission of Kansas and the Corporation Commission of Oklahoma) is
     required in connection therewith. Copies of the Prospectus must be filed
     with the State Corporation Commission of Kansas, but this information
     filing is not a prerequisite to the authorization, issuance or sale of the
     Notes. We express no opinion as to compliance with Blue Sky laws or the
     Public Utility Holding Company Act of 1935, as amended.

          (v)    The Purchase Contract has been duly authorized, executed and
     delivered by the Company.

          (vi)   With minor exceptions relating to the use of streets and
     highways outside incorporated communities in New Mexico, Oklahoma, and
     Texas and with respect to the right of the City of Pampa, Texas, to
     purchase properties of the Company within its limits at a purchase price to
     be determined upon appraisal, the Company holds valid franchises in the
     territory in which it operates which have no burdensome restrictions and
     are adequate to conduct its business in such territory.

          (vii)  The issuance of and the sale by the Company to you of the Notes
     pursuant to the terms of the Purchase Contract and the fulfillment by the
     Company of the other terms thereof will not result in a breach of any of
     the terms or provisions of, or constitute a default under, the Company's
     Restated Articles of Incorporation, as amended, its By-Laws, or any
     indenture, mortgage, deed of trust, or other agreement or instrument known
     to us to which the Company is now a party.

          (viii) The facsimile signature of an Executive Vice President, a
     Senior Vice President or a Vice President of the Company in lieu of his or
     her manual signature on the Notes and the facsimile signature of the
     Secretary or an Assistant Secretary of the Company attesting the corporate
     seal in lieu of his or her manual signature on the Notes have been duly and
     properly authorized by the Board of Directors of the Company, are not
     inconsistent with the provisions of the Restated Articles of Incorporation,
     as amended, or By-Laws of the Company and are valid and effective under the
     laws of the State of New Mexico; and the facsimile signatures of such
     officers on the Notes have

                                      C-3

 
     the same legal effect as though they had manually signed and attested the
     Notes as such respective officers.

          (ix)  At the time the Registration Statement became effective and at
     the date of the Purchase Contract, the Registration Statement complied,
     and, at the date hereof, the Prospectus, as it may have been amended or
     supplemented, complies, as to form in all material respects with the
     requirements of the 1933 Act and the applicable instructions, rules and
     regulations thereunder, or pursuant to said instructions, rules and
     regulations are deemed to have complied or to comply therewith, although we
     do not express any opinion as to the financial statements (including the
     notes thereto) or other financial or statistical data included or
     incorporated by reference therein.

          We do not know of any legal or governmental proceeding (pending or
threatened) required to be described in the Registration Statement or the
Prospectus, as amended or supplemented to the date hereof, which is not
described as required, nor of any contract or document of a character required
to be described in the Registration Statement or the Prospectus, as amended or
supplemented to the date hereof, or to be filed as an exhibit to the
Registration Statement which is not described or filed as required.

          In connection with this opinion, we have participated in discussions
with officers and representatives of the Company, in certain of which your
representatives and counsel also participated and at which the affairs of the
Company and the contents of the Registration Statement and the Prospectus were
discussed. There is no assurance that all possible material facts as to the
Company were disclosed to us or that our familiarity with the Company or the
operations in which it is engaged is such that we have necessarily recognized
the materiality of such facts as were disclosed, and we have to a large extent
relied upon statements of officers and representatives of the Company as to the
materiality of those facts disclosed to us. We are not passing upon and do not
assume any responsibility for the accuracy, completeness or fairness of the
statements contained in the Registration Statement and the Prospectus. Subject
to the foregoing, and to the other limitations and qualifications expressed in
this letter, we may state that nothing has come to our attention that would lead
us to believe that the Registration Statement, when it became effective, or at
the date of the Purchase Contract, contained an untrue statement of a material
fact or omitted to state a material fact required to be stated therein or
necessary to make the statements therein not misleading, or that, at the date
the Prospectus Supplement was filed with the Securities and Exchange Commission,
the Prospectus included, or, at the date

                                      C-4

 
hereof, the Prospectus, as it may have been amended or supplemented, includes an
untrue statement of a material fact or omitted, or omits, to state a material
fact necessary in order to make the statements therein, in the light of the
circumstances under which they were made, not misleading; provided, that we do
not express any belief as to the financial statements (including the notes
thereto) or other financial or statistical data contained or incorporated by
reference in the Registration Statement or the Prospectus, or any amendment or
supplement thereto, as to any information contained therein furnished to the
Company in writing by any Purchaser expressly for use therein or as to the
Statement of Eligibility.

          This opinion is limited to the laws of the State of New York and the
State of New Mexico and the federal law of the United States of America.  We
have relied, with your consent, as to all matters governed by the laws of the
State of Oklahoma, upon the opinion of Rainey, Ross, Rice & Binns, and as to all
matters governed by the laws of the State of Kansas, upon the opinion of
Foulston & Siefkin.  In addition, we are not opining herein with respect to the
securities or "blue sky" laws of any state.  Finally, this opinion speaks as of
the date hereof and we undertake no responsibility to advise you of any change
in circumstances after the date hereof.

          The Chase Manhattan Bank, is hereby authorized to rely upon this
letter as if this letter were addressed to it.  LeBoeuf, Lamb, Greene & MacRae,
L.L.P., counsel for the Company, and Cahill Gordon & Reindel, counsel for the
Purchasers, are hereby authorized to rely upon this letter as to matters
governed by the laws of the State of New Mexico as if this letter were addressed
to them.  This letter is not being delivered for the benefit of, nor may it be
relied upon by, the holders of the Notes or any other party to which it is not
specifically addressed or to which reliance has not expressly been permitted
hereby.

                                    Very truly yours,

                                 C-5

 
                                                                       Exhibit D
                                                                              to
                                                          Note Purchase Contract
                                                          ----------------------

                  [LETTERHEAD OF RAINEY, ROSS, RICE & BINNS]

[Purchasers]



Ladies and Gentlemen:



          This opinion is being furnished to you in connection with the sale by
Southwestern Public Service Company (the "Company") of $100,000,000 aggregate
principal amount of Senior Notes of the Company (the "Notes"), which are
registered pursuant to the registration statement (File No. 333-05199) of the
Company for the registration under the Securities Act of 1933, as amended (the
"1933 Act"), of up to $220,000,000 aggregate principal amount of securities,
including the Notes. This opinion is being delivered to you pursuant to Section
8(d) of the Purchase Contract, dated February 25, 1999 (the "Purchase
Contract"), between the Company and the several purchasers named therein (the
"Purchasers"). Unless otherwise stated, defined terms used herein shall have the
respective meanings given them in the Purchase Contract.

          Subject to the limitations and qualifications set forth herein, it is
our opinion that:

          (i)  Insofar as the laws of Oklahoma are concerned, the issuance of
     the Notes has been duly authorized by all necessary corporate action of the
     Company and (assuming that the Notes delivered today to you have been
     authenticated by a duly authorized officer of the Trustee), such Notes have
     been validly issued, are in due legal form and are the legal, valid, and
     enforceable obligations of the Company.

          (ii) The Company is duly registered in Oklahoma as a foreign
     corporation and is legally authorized to own property and to carry on the
     business in which it is engaged in Oklahoma.

                                      D-1

 
          (iii) No approvals or authorizations of the Corporation Commission of
     Oklahoma are required for the valid sale of the Notes under the Purchase
     Contract and no other approval of any Oklahoma public regulatory body is
     required in connection with the authorization, issuance and sale of the
     Notes by the Company. We express no opinion as to compliance by the Company
     with Blue Sky laws.

          (iv)  With minor exceptions relating to the use of streets and
     highways outside of incorporated communities in Oklahoma, the Company holds
     valid franchises in the territory of Oklahoma in which it operates which
     are without burdensome restrictions and are adequate for the conduct of the
     business of the Company in such territory.


          (v)  The statements stated in the Registration Statement and the
     Prospectus to be set forth in the reliance upon us, as experts, are
     correct.

          This opinion is limited to the laws of the State of Oklahoma. In
addition, we are not opining herein with respect to the securities or "blue sky"
laws of any state. Finally, this opinion speaks as of the date hereof and we
undertake no responsibility to advise you of any change in circumstances after
the date hereof.

          The Chase Manhattan Bank is hereby authorized to rely upon this letter
as if this letter were addressed to it. LeBoeuf, Lamb, Greene & MacRae, L.L.P.
and Hinkle, Cox, Eaton, Coffield & Hensley, counsel for the Company, and Cahill
Gordon & Reindel, counsel for the Purchasers, are hereby authorized to rely upon
this letter as to matters governed by the laws of the State of Oklahoma as if
this letter were addressed to them. This letter is not being delivered for the
benefit of, nor may it be relied upon by, the holders of the Notes or any other
party to which it is not specifically addressed or to which reliance has not
expressly been permitted hereby.

                                    Very truly yours,

                                      D-2

 
                                                                       Exhibit E
                                                                              to
                                                          Note Purchase Contract
                                                          ----------------------

                      [LETTERHEAD OF FOULSTON & SIEFKIN]

[Purchasers]



Ladies and Gentlemen:


          We have acted as counsel to Southwestern Public Service Company (the
"Company") in connection with the sale by the Company of $100,000,000 aggregate
principal amount of [Senior] Notes of the Company (the "Notes"), which are
registered pursuant to the registration statement (File No. 333-05199) of the
Company for the registration under the Securities Act of 1933, as amended (the
"1933 Act"), of up to $220,000,000 aggregate principal amount of securities,
including the Notes. This opinion is being delivered to you pursuant to Section
8(d) of the Purchase Contract, dated February 25, 1999 (the "Purchase
Contract"), between the Company and the several purchasers named therein (the
"Purchasers"). Unless otherwise stated, defined terms used herein shall have the
respective meanings given them in the Purchase Contract.

          On the basis of the foregoing, and subject to the limitations and
qualifications set forth herein, it is our opinion that:

          (i)  No approval or authorization of any Kansas public regulatory body
     (including the State Corporation Commission of the State of Kansas) is
     required for the valid authorization, issue and sale of the Notes pursuant
     to the terms of the Purchase Contract. Copies of the Registration Statement
     and the Prospectus have been filed with the State Corporation Commission of
     the State of Kansas, but this information filing is not a prerequisite to
     the authorization, issuance, or sale of the Notes. We express no opinion as
     to the compliance by the Company with Blue Sky laws.

          (ii) The Company is duly registered in the State of Kansas as a
     foreign corporation and is legally authorized

                                      E-1

 
     to own property and to carry on the business in which it is engaged in
     Kansas.

          (iii) The Company holds valid franchises or other authorities in the
     territory in Kansas in which it operates which are without burdensome
     restrictions and are adequate for the conduct of the business of the
     Company in such territory.

          (iv) The statements stated in the Registration Statement and
     Prospectus to be set forth in reliance upon us, as experts, are correct.

          This opinion is limited to the laws of the State of Kansas. In
addition, we are not opining herein with respect to the securities or "blue sky"
laws of any state. Finally, this opinion speaks as of the date hereof and we
undertake no responsibility to advise you of any change in circumstances after
the date hereof.

          The Chase Manhattan Bank is hereby authorized to rely upon this letter
as if this letter were addressed to it. LeBoeuf, Lamb, Greene & MacRae, L.L.P.
and Hinkle, Cox, Eaton, Coffield & Hensley, counsel for the Company, and Cahill
Gordon & Reindel, counsel for the Purchasers, are hereby authorized to rely upon
this letter as to matters governed by the laws of the State of Kansas as if this
letter were addressed to them. This letter is not being delivered for the
benefit of, nor may it be relied upon by, the holders of the Notes or any other
party to which it is not specifically addressed or to which reliance has not
expressly been permitted hereby.

                                    Very truly yours,


                                      E-2

 
                                                                       Exhibit F
                                                                              to
                                                          Note Purchase Contract
                                                          ----------------------


                    [LETTERHEAD OF CAHILL GORDON & REINDEL]

[Purchasers]



Ladies and Gentlemen:

          We have acted as counsel for the Purchasers named in the Purchase
Contract, dated February 25, 1999 (the "Purchase Contract"), among you and
Southwestern Public Service Company, a New Mexico corporation (the "Company"),
in connection with the sale by the Company to you, severally, and the purchase
by you, severally, of $100,000,000 aggregate principal amount of Senior Notes of
the Company (the "Notes"), being issued under its Indenture, dated as of
February 1, 1999, to The Chase Manhattan Bank, National Association, as trustee,
and all indentures supplemental thereto, including the Supplemental Indenture
dated as of March 1, 1999 creating the Notes (the "Supplemental Indenture")
(said Indenture dated as of February 1, 1999 and all indentures supplemental
thereto being hereinafter collectively referred to as the "Indenture").

          In rendering our opinions set forth herein, we have examined
originals, photocopies or conformed copies certified to our satisfaction of all
corporate records, agreements, instruments and documents of the Company,
certificates of public officials and other certificates and opinions, and have
made such other investigations as we deem necessary, in connection with the
opinions set forth herein.  In such examination, we have, without any
independent investigation or verification, assumed the genuineness of all
signatures, the authenticity of all documents submitted to us as originals and
the conformity to originals of all documents submitted to us as photocopies or
conformed copies.

          Based upon the foregoing, and subject to the assumptions set forth
herein, we advise you that in our opinion (based to the extent indicated below
upon the opinions of other counsel hereinafter mentioned):

          (i) The Indenture has been duly and validly authorized, executed and
     delivered by the Company and (assuming

                                      F-1

 
     the Indenture has been duly authorized, executed and delivered by the
     Trustee) constitutes a legal, valid and binding obligation of the Company,
     enforceable in accordance with its terms, except as enforcement thereof may
     be limited by laws and principles of equity affecting generally the
     enforcement of creditors' rights, including without limitation bankruptcy
     and insolvency laws and state laws which affect the enforcement of certain
     remedial provisions of the Indenture.

          (ii)  The Indenture is qualified under the Trust Indenture Act of
     1939, as amended.

          (iii) The Notes are in due and proper form and the issuance and sale
     of the Notes by the Company have been duly authorized by all necessary
     corporate action, and, when duly executed, authenticated and delivered to
     the Purchasers pursuant to the Purchase Contract against payment of the
     consideration set forth therein, the Notes will be legal, valid and binding
     obligations of the Company enforceable (subject to the exceptions and
     limitations referred to in paragraph (i) hereof) in accordance with their
     terms.

          (iv) The Purchase Contract has been duly authorized, executed and
     delivered by the Company.

          (v)  The Notes and the Indenture conform as to legal matters to the
     description of the terms thereof contained in the Registration Statement
     and the Prospectus, as amended or supplemented to the date hereof.

          (vi) The Registration Statement is effective under the 1933 Act and,
     to the best of our knowledge, no proceedings for a stop order have been
     instituted or are pending or threatened under Section 8(d) of the 1933 Act;
     and, at the time the Registration Statement became effective, the
     Registration Statement complied, and, at the date hereof, the Prospectus,
     as amended or supplemented to the date hereof, complies, as to form in all
     material respects with the requirements of the 1933 Act and the applicable
     instructions, rules and regulations thereunder, or pursuant to said
     instructions, rules and regulations are deemed to have complied or to
     comply therewith, although we do not express any opinion as to the
     financial statements (including the notes thereto) or other financial data
     or statistical data included or incorporated by reference therein.

          We have participated in discussions with officers and other
representatives of the Company, counsel for the Company,

                                      F-2

 
representatives of the Company's independent public accountants and your
representatives at which the contents of the Registration Statement and the
Prospectus and related matters were discussed and, although we are not passing
upon and do not assume any responsibility for the accuracy, completeness or
fairness of the statements contained in the Registration Statement and the
Prospectus (except to the extent referred to in paragraph (v) above), on the
basis of the foregoing (relying as to materiality to a large extent upon the
opinions of officers and other representatives of the Company), no facts have
come to our attention that would lead us to believe that either the Registration
Statement, when it became effective, contained an untrue statement of a material
fact or omitted to state a material fact required to be stated therein or
necessary to make the statements therein not misleading, or that, at the date
the Prospectus Supplement was filed with the Commission, the Prospectus
included, or, at the date hereof, the Prospectus, as it may have been amended or
supplemented, includes an untrue statement of a material fact or omitted, or
omits, to state a material fact necessary in order to make the statements
therein, in the light of the circumstances under which they were made, not
misleading (it being understood that we do not make any comment with respect to
the financial statements (including the notes thereto) or other financial or
statistical data contained or incorporated by reference in the Registration
Statement or the Prospectus, or any amendment or supplement thereto or with
respect to information contained therein furnished to the Company in writing by
any Purchaser expressly for use therein or as to the Form T-1).

          This opinion is limited to the laws of the State of New York and the
federal law of the United States of America. Accordingly, in rendering the
opinions above, we have relied, with your consent, as to all matters governed by
the laws of the States of New Mexico and Texas, upon the opinion of Hinkle, Cox,
Eaton, Coffield & Hensley LLP, as to all matters governed by the laws of the
States of Oklahoma, upon the opinion of Rainey, Ross, Rice & Binns, and as to
all matters governed by the laws of the State of Kansas, upon the opinion of
Foulston & Siefkin, each of even date herewith addressed to you.

                                    Very truly yours,

                                      F-3

 
                                                                       Exhibit G
                                                                              to
                                                          Note Purchase Contract
                                                          ----------------------

                   CONTENTS OF LETTER OF ARTHUR ANDERSEN LLP

          The letter of Arthur Andersen LLP will confirm that they are
independent public accountants within the meaning of the 1933 Act and the 1933
Act Regulations, and will state in effect that:

          (i)  in their opinion, the consolidated financial statements and
     supporting financial schedules audited by them and incorporated by
     reference in the Registration Statement comply as to form in all material
     respects with the applicable accounting requirements of the 1933 Act and
     the 1934 Act and the applicable respective published rules and regulations
     thereunder;

          (ii) on the basis of a limited review (but not an audit in accordance
     with generally accepted auditing standards) of the unaudited consolidated
     condensed financial statements, if any, included in the Incorporated
     Documents and of the latest available interim consolidated financial
     statements of the Company, a reading of any unaudited pro forma financial
     statements included in the Prospectus or the Incorporated Documents, a
     reading of all recent minutes of meetings of the Board of Directors of the
     Company and the Executive, Audit and Pricing Committees thereof (or for
     meetings for which minutes had not yet been prepared, discussions with a
     Company officer of the actions taken thereat) and of the shareholder of the
     Company, and discussions with officers of the Company responsible for
     financial and accounting matters and such other inquiries and procedures as
     may be specified in such letter, nothing came to their attention which
     caused them to believe that:

          (iii) any material modifications should be made to the unaudited
     consolidated condensed financial statements, if any, included in the
     Incorporated Documents for them to be in conformity with generally accepted
     accounting principles, or

          (iv) the unaudited consolidated condensed financial statements, if
     any, included in the Incorporated Documents do not comply as to form in all
     material respects with the applicable accounting requirements of the 1934
     Act and the related published 1934 Act Regulations, or said consoli-

                                      G-1

 
     dated condensed financial statements are not in conformity with generally
     accepted accounting principles applied on a basis substantially consistent
     with that of the audited consolidated financial statements incorporated by
     reference therein, or

          (v)  the unaudited [income statement amounts], if any, included in the
     Prospectus Supplement do not agree with the amounts set forth in the
     unaudited consolidated financial statements for those same periods or were
     not determined on a basis substantially consistent with that of the audited
     statements of income, or

          (vi) any unaudited pro forma financial statements included in the
     Prospectus or the Incorporated Documents do not comply as to form in all
     material respects with the applicable accounting requirements of Rule 11-02
     of Regulation S-X or the pro forma adjustments have not properly been
     applied to the historical amounts in the compilation of those statements,
     or

          (vii)   (A)  there was any change in the consolidated capital stock,
     or any increase in the long-term debt of the Company, or any decrease in
     consolidated net assets, at a specified date not more than three days prior
     to the date of such letter as compared with the corresponding amounts shown
     in the most recent consolidated balance sheet or condensed balance sheet
     incorporated by reference in the Prospectus, or

               (B)  there was any decrease in consolidated operating revenues or
     net income for the period from the date of the latest consolidated balance
     sheet or condensed balance sheet incorporated by reference in the
     Prospectus to a specified date not later than three days prior to the date
     of such letter as compared to such amounts for the corresponding period
     during the previous year,

     [except in all instances for changes, increases or decreases which the
     Prospectus discloses have occurred or may occur or which are disclosed in
     such letter;]

          (viii) they have carried out certain procedures and made certain
     findings, specified in such letter, with respect to certain amounts and
     percentages included in the Prospectus and the Incorporated Documents and
     such other items as the Representative may reasonably request.

                                      G-2