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                                                                   EXHIBIT 3.A.1


                         EL PASO TENNESSEE PIPELINE CO.

     CERTIFICATE OF DESIGNATION, PREFERENCES AND RIGHTS OF PREFERRED STOCK
                    BY RESOLUTION OF THE BOARD OF DIRECTORS
                      PROVIDING FOR AN ISSUE OF 1,210,000
                      SHARES OF PREFERRED STOCK DESIGNATED
              "6 1/4% CUMULATIVE JUNIOR PREFERRED STOCK, SERIES C"
                          -------------------------

         I, David L. Siddall, Corporate Secretary of El Paso Tennessee Pipeline
Co. (hereinafter referred to as the "Corporation"), a corporation organized and
existing under the General Corporation Law of the State of Delaware, in
accordance with the provisions of Section 151 thereof, DO HEREBY CERTIFY:

         That pursuant to authority conferred upon the Board of Directors by
the Certificate of Incorporation, as amended, of said Corporation, the Board of
Directors, by unanimous written consent, pursuant to Section 141(f) of the
General Corporation Law of the State of Delaware, dated as of February 26,
1998, adopted a resolution providing for the issuance of a series of Preferred
Stock, to be designated "6 1/4% Cumulative Junior Preferred Stock, Series C,"
which resolution is as follows:

         RESOLVED, that pursuant to the authority vested in the Board of
Directors of the Corporation by the Certificate of Incorporation, as amended
(as such may be further amended from time to time, the "Certificate of
Incorporation"), a series of Preferred Stock, par value $0.01 per share, of the
Corporation (the "Preferred Stock") be, and hereby is, created to be designated
"6 1/4% Cumulative Junior Preferred Stock, Series C" (hereinafter referred to
as the "Series C Preferred Stock"), consisting of 1,210,000 shares, and the
designations, powers, preferences and relative and other special rights and the
qualifications, limitations and restrictions of the Series C Preferred Stock
are hereby fixed and stated to be as follows (all terms used herein that are
defined in the Certificate of Incorporation shall be deemed to have the
meanings provided therein):

         SECTION 1. Dividends. (a) The dividend rate on the Series C Preferred
Stock shall be 6 1/4% of $50 per share of Series C Preferred Stock per annum.
Dividends on shares of the Series C Preferred Stock shall accrue, whether or
not declared, on a daily basis from the date of issuance of such shares.
Accrued but unpaid dividends shall not bear interest.

         (b) Dividends on the Series C Preferred Stock shall be payable, when,
as and if declared by the Board of Directors of the Corporation out of assets
legally available therefor, annually on the last day of January in each year
(each, a "Dividend Payment Date"), with the first dividend payment date being
the next Dividend Payment Date following the date of issuance. Dividends on
each Dividend Payment Date will be payable to holders of record of the Series C
Preferred Stock as they appear on the stock books of the Corporation on a
record date, not more than 60 days preceding such Dividend Payment Date, fixed
for such purpose by the Board of Directors in advance of such Dividend Payment
Date.  Dividends payable on the Series C Preferred Stock for any period shorter
than a year shall be computed on the basis of a 360-day year of twelve 30-day
months. The Series C Preferred Stock shall rank on a parity with each other
series of Preferred Stock as to the payment of dividends, except to the extent
otherwise provided in Section 5 hereof or in the resolution or resolutions
providing for the issuance of such other series.

         SECTION 2. Voting. The Series C Preferred Stock shall not have any
voting rights except as required by law or the Certificate of Incorporation, or
as hereinafter set forth:
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         (a) Whenever, at any time or times, dividends payable on the Series C
Preferred Stock shall be in arrears for dividend periods, whether or not
consecutive, containing in the aggregate a number of days equivalent to six
calendar quarters, the holders of outstanding Series C Preferred Stock shall
have the exclusive right, voting as a separate series from all other series of
Preferred Stock and classes of capital stock of the Corporation, at each
meeting of the stockholders held for the purpose of electing directors, to
elect two directors of the Corporation, until such time as all dividends
accumulated on the Series C Preferred Stock and in arrears shall have been paid
in full or declared and set apart for payment, at which time the right of the
holders of the Series C Preferred Stock to vote pursuant to the provisions of
this paragraph (a) shall terminate, subject to revesting in the event of each
and every subsequent default of the character and for the time above mentioned.

         At any time when voting rights shall, pursuant to the provisions of
this paragraph (a), be vested in the Series C Preferred Stock, the number of
directors of the Corporation shall be automatically increased, to the extent
necessary, so that two directors may be elected by the holders of the Series C
Preferred Stock and a proper officer of the Corporation shall, upon the written
request of the holders of record of at least ten percent in aggregate
liquidation value of the Series C Preferred Stock then outstanding, addressed
to the Secretary of the Corporation, call a special meeting of holders of the
Series C Preferred Stock. Such meeting shall be held at the earliest
practicable date but in no event shall a special meeting be held if the annual
meeting of stockholders of the Corporation is to be held within 90 days of the
receipt by the Secretary of the Corporation of such request.  If such meeting
shall not be called by the proper officer of the Corporation as required within
20 days after personal service of the said written request upon the Secretary
of the Corporation, or within 20 days after mailing the same within the United
States of America by certified or registered mail, return receipt requested,
addressed to the Secretary of the Corporation at its principal office (such
mailing to be evidenced by the registry receipt issued by the postal
authorities), then the holders of record of at least ten percent in aggregate
liquidation value of the Series C Preferred Stock then outstanding may
designate in writing one of their number to call such meeting, and such meeting
may be called by such person designated upon the notice required for annual
meetings of stockholders but in no event shall a special meeting be held if the
annual meeting of stockholders of the Corporation is to be held within 90 days
of the receipt by the Secretary of the Corporation of such request.  Any holder
of the Series C Preferred Stock so designated shall have access to the stock
books of the Corporation for the purpose of causing a meeting of stockholders
to be called pursuant to these provisions.  Upon any termination of the right
of the holders of the Series C Preferred Stock to vote for directors as a class
as described in this paragraph (a), the term of office of the directors so
elected as described in this paragraph (a) shall automatically terminate and
the number of directors shall be reduced accordingly.

         (b) At any meeting so called pursuant to paragraph (a) above, and at
any other meeting of stockholders held for the purpose of electing directors at
which the holders of the Series C Preferred Stock shall have the right to elect
directors as provided in paragraph (a) above, the presence in person or by
proxy of a majority in voting power of the outstanding shares of the Series C
Preferred Stock shall be required to constitute a quorum thereof for the
election of any director by the holders of the Series C Preferred Stock.

         At any such meeting or adjournment thereof, (x) the absence of the
required quorum of the Series C Preferred Stock shall not prevent the election
of directors other than those to be elected by the Series C Preferred Stock and
the absence of a quorum for the election of such other directors shall not
prevent the election of the directors to be elected by the Series C Preferred
Stock, and (y) in the absence of the required quorum of the Series C Preferred
Stock, a majority in voting power of the holders of Series C Preferred Stock
present in person or by proxy shall have power to adjourn the meeting, subject
to applicable law, but
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only with respect to the election of directors which they are entitled to elect
from time to time without notice other than announcement at the meeting until a
quorum shall be present.

         (c) If by reason of any resignation, retirement, disqualification,
death or removal there are not in office all such directors that the holders of
the Series C Preferred Stock are entitled to elect pursuant to paragraph (a)
above, then any such vacancy shall be filled only by the remaining director
elected by such holders or, only in the event there is no such remaining
director, by the holders of the Series C Preferred Stock entitled to vote
thereon.

         Promptly after the right of the holders of the Series C Preferred
Stock to fill any vacancy as set forth in the immediately preceding paragraph
arises, the Board of Directors may cause a special meeting of the holders of
Series C Preferred Stock entitled to vote thereon to be held for the purpose of
filling such vacancy, and such vacancy shall be filled at any such special
meeting. Such meeting shall be held at the earliest practicable date, but in no
event shall a special meeting be held if the annual meeting of stockholders of
the Corporation is to be held within 90 days of the occurrence of such vacancy.

         Notwithstanding the immediately preceding paragraph, at any time after
the right of the holders of the Series C Preferred Stock to fill any vacancy as
set forth above in the first paragraph of this paragraph (c) arises, a proper
officer of the Corporation shall, upon the written request of the holders of
record of at least ten percent in aggregate liquidation value of the Series C
Preferred Stock then outstanding, addressed to the Secretary of the
Corporation, call a special meeting of holders of the Series C Preferred Stock.
Such meeting shall be held at the earliest practicable date but in no event
shall a special meeting be held if the annual meeting of stockholders of the
Corporation is to be held within 90 days of the occurrence of such vacancy. If
such meeting shall not be called by the proper officer of the Corporation as
required within 20 days after personal service of the said written request upon
the Secretary of the Corporation, or within 20 days after mailing the same
within the United States of America by registered mail addressed to the
Secretary of the Corporation at its principal office (such mailing to be
evidenced by the registry receipt issued by the postal authorities), then the
holders of record of at least ten percent in aggregate liquidation value of the
Series C Preferred Stock then outstanding may designate in writing one of their
number to call such meeting, and such meeting may be called by such person
designated upon the notice required for annual meetings of stockholders and
shall be held at the place at which the last preceding annual meeting of the
stockholders of the Corporation was held. Any holder of the Series C Preferred
Stock so designated shall have access to the stock books of the Corporation for
the purpose of causing a meeting of stockholders to be called pursuant to these
provisions.

         SECTION 3. Restrictions on Dividends and Stock Repurchases. Subject to
any additional restrictions or limitations contained in the Certificate of
Incorporation, if any, so long as any shares of Series C Preferred Stock remain
outstanding, unless full cumulative dividends on the outstanding shares of
Series C Preferred Stock for all past dividend periods have been paid, or
declared and set apart for payment, dividends may not be  paid or declared and
other distributions may not be made upon any class or series of stock of the
Corporation ranking junior to or on a parity with the Series C Preferred Stock
as to dividends or rights upon dissolution, liquidation or winding up of the
Corporation nor may any such class or series of stock of the Corporation be
redeemed, purchased, retired or otherwise acquired by the Corporation, in
either case without the consent, given in person or by proxy, either in writing
or by vote at any annual meeting or at a special meeting called for that
purpose, of the holders of at least a majority in voting power of the
outstanding shares of Series C Preferred Stock present in person or by proxy at
such meeting, provided that a quorum, consisting of at least a majority in
voting power of the then outstanding shares of Series C Preferred Stock is
present; provided, however, that, notwithstanding the foregoing provisions of
this Section 3 (but subject to any restrictions or limitations to the contrary
contained in the
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Certificate of Incorporation), the Corporation may at any time redeem, purchase
or acquire, out of funds legally available therefor, shares of stock ranking
junior to or on a parity with the Series C Preferred Stock as to dividends and
rights upon liquidation, dissolution and winding up of the Corporation in
exchange for, or out of net cash proceeds from a substantially concurrent sale
of, other shares of any stock of the Corporation ranking junior to the Series C
Preferred Stock as to dividends and rights upon liquidation, dissolution and
winding up.

         SECTION 4. Ranking. (a) Any class or series of stock of the
Corporation shall be deemed to rank:  (i) prior to the Series C Preferred Stock
as to the payment of dividends or as to distributions of assets upon
liquidation, dissolution or winding up, as the case may be, if the holders of
such class or series shall be entitled to the receipt of dividends or of
amounts distributable upon liquidation, dissolution or winding up, as the case
may be, in preference or priority to the holders of Series C Preferred Stock;
(ii) on a parity with the Series C Preferred Stock as to the payment of
dividends, whether or not the dividend rates or dividend payment dates thereof
be different from those of the Series C Preferred Stock, if the holders of such
class or series of stock and the holders of the Series C Preferred Stock shall
be entitled to the receipt of dividends in proportion to their respective
amounts of accrued and unpaid dividends per share, without preference or
priority one over the other, and on a parity with the Series C Preferred Stock
as to the distribution of assets upon liquidation, dissolution or winding up,
whether or not the liquidation prices per share thereof be different from those
of the Series C Preferred Stock, if the holders of such class or series of
stock and the holders of the Series C Preferred Stock shall be entitled to the
receipt of amounts distributable upon liquidation, dissolution or winding up in
proportion to their respective liquidation preferences, without preference or
priority one over the other; and (iii) junior to the Series C Preferred Stock
as to the payment of dividends or as to the distribution of assets upon
liquidation, dissolution or winding up, as the case may be, if the holders of
Series C Preferred Stock shall be entitled to receipt of dividends or of
amounts distributable upon liquidation, dissolution or winding up, as the case
may be, in preference or priority to the holders of shares of such class or
series.

         (b) Except for the Common Stock, par value $0.01 per share, of the
Corporation (as such may be constituted from time to time, the "Common Stock"),
each other class and series of stock of the Corporation existing on the date of
the adoption of this Certificate of Designation, Preferences and Rights of
Preferred Stock shall be deemed to rank prior to the Series C Preferred Stock
both as to the payment of dividends and as to the distribution of assets upon
liquidation, dissolution or winding up. The Common Stock shall be deemed to
rank junior to the Series C Preferred Stock both as to the payment of
dividends and as to the distribution of assets upon liquidation, dissolution or
winding up.

         SECTION 5. Liquidation Rights. (a) The amount that the holders of
Series C Preferred Stock shall be entitled to receive in the event of any
dissolution, liquidation or winding up of the affairs of the Corporation,
whether voluntary or involuntary (collectively, a "Liquidation"), shall be
$50.00 per share, plus an amount equal to all accrued and unpaid dividends to
the date of Liquidation, and no more. After such amount is paid in full, no
further distributions or payments shall be made in respect of shares of Series
C Preferred Stock, such shares of Series C Preferred Stock shall no longer be
deemed to be outstanding or be entitled to any powers, preferences, rights or
privileges, including any voting rights, and certificates representing such
shares of Series C Preferred Stock shall be surrendered for cancellation to the
Corporation.

         (b) In the event of any liquidation, dissolution or winding up of the
affairs of the Corporation, then, before any distribution or payment shall be
made to the holders of any class or series of stock of the Corporation ranking
junior to the Series C Preferred Stock, the holders of the Series C Preferred
Stock (subject to the rights of the holders of any stock ranking prior to the
Series C Preferred Stock as to rights
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on liquidation, dissolution and winding up) shall be entitled to be paid in
full the amounts set forth in paragraph (a) of this Section 5.  After such
payment shall have been made in full to the holders of the Series C Preferred
Stock, the remaining assets and funds of the Corporation shall be distributed
among the holders of the stock of the Corporation ranking junior in respect
thereof to the Series C Preferred Stock according to their respective rights.
In the event that the assets of the Corporation available for distribution to
holders of Series C Preferred Stock shall not be sufficient to make the payment
herein required to be made in full and to pay in full the liquidation
preference on all other shares of stock of the Corporation ranking on a parity
with the Series C Preferred Stock as to amounts distributable upon dissolution,
liquidation or winding up of the Corporation, such assets shall be distributed
to the holders of the respective shares of Series C Preferred Stock and any
such other parity stock pro rata in proportion to the full amounts payable upon
the shares of Series C Preferred  Stock and any such other parity stock if all
amounts payable thereon were paid in full.

         SECTION 6. Maturity. Unless otherwise redeemed as provided herein, the
term of the Series C Preferred Stock shall be perpetual.

         IN WITNESS WHEREOF, said El Paso Tennessee Pipeline Co. has caused
this Certificate of Designation, Preferences and Rights of Preferred Stock to
be signed by David L. Siddall, as Corporate Secretary, this 4th day of March
1998.

                                        EL PASO TENNESSEE PIPELINE CO.


                                        By:
                                           --------------------------------
                                                    David L. Siddall
                                                  Corporate Secretary