EXHIBIT 3.1(b)

                                                        CERTIFICATE OF AMENDMENT
                                                        FILED
                                                        APRIL 23, 1987
                                                        JANE BURGIO
                                                        SECRETARY OF STATE

                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                                 PUBLIC SERVICE
                          ENTERPRISE GROUP INCORPORATED

INCREASING AUTHORIZED COMMON STOCK FROM 150,000,000 SHARES TO 500,000,000
SHARES, AUTHORIZING A NEW CLASS OF 50,000,000 SHARES OF PREFERRED STOCK,
REQUIRING 80% SHAREHOLDER APPROVAL OF CERTAIN MERGERS AND OTHER BUSINESS
COMBINATIONS UNDER CERTAIN CONDITIONS, CLASSIFYING THE BOARD OF DIRECTORS INTO
THREE CLASSES OF DIRECTORS, REQUIRING 80% SHAREHOLDER APPROVAL FOR CERTAIN
BY-LAW AMENDMENTS AND LIMITING PERSONAL LIABILITY OF DIRECTORS AND OFFICERS.

                             EFFECTIVE APRIL 23, 1987

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                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                  PUBLIC SERVICE ENTERPRISE GROUP INCORPORATED

      Public Service Enterprise Group Incorporated, a New Jersey corporation,
does hereby certify, pursuant to subsection 14A:9-4(3) of the New Jersey
Business Corporation Act, as amended, that:

      1. The name of this corporation is "Public Service Enterprise Group
Incorporated".

      2. The date of adoption of the amendments set forth in this Certificate of
Amendment by the stockholders was April 21, 1987.

      3. The number of shares entitled to vote on the amendments set forth in
this Certificate of Amendment was 134,981,136 shares of Common Stock.

      4. (a) Article 3 of the Certificate of Incorporation dated July 25, 1985
of this corporation has been amended, by vote of the stockholders of this
corporation, so as to increase the authorized Common Stock from 150,000,000
shares to 500,000,000 shares.

      (b) The number of votes cast by the holders of Common Stock for and
against said amendment were as follows:

                        For                        Against
                    94,590,268                    10,575,620

      5. (a) Article 3 of the Certificate of Incorporation dated July 25, 1985
of this corporation has been further amended, by vote of the stockholders of
this corporation, to authorize a new class of 50,000,000 shares of Preferred
Stock.

      (b) The number of votes cast by the holders of Common Stock for and
against said amendment were as follows:

                        For                        Against
                    78,616,663                    18,109,174

      6. (a) Article 8 of the Certificate of Incorporation dated July 25, 1985
of this corporation has been amended, by vote of the stockholders of this
corporation, so as to add a provision to limit the personal liability of
directors and officers.

      (b) The number of votes cast by the holders of Common Stock for and
against said amendment were as follows:

                        For                        Against
                    94,974,819                    8,797,560

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      7. (a) The Certificate of Incorporation dated July 25, 1985 of this
corporation has been amended by adding new Articles 9, 10 and 11 to (i) require
80% shareholder approval of certain mergers and other business combinations
unless certain fair price voting and procedural requirements are met or the
transaction is approved by a majority of disinterested directors, (ii) classify
the Board of Directors, (iii) require 80% shareholder approval for certain
by-law amendments, and (iv) make related changes; and as a result of said
amendments, existing Articles 9 and 10 of the Certificate of Incorporation dated
July 25, 1985 of this corporation have been deleted and existing Articles 11
through 14 of said Certificate of Incorporation have been renumbered as Articles
12 through 15.

      (b) The number of votes cast by the holders of Common Stock for and
against said amendments were as follows:

                       For                         Against
                    75,011,767                    22,322,471

      8. The amendments of the Certificate of Incorporation dated July 25, 1985
of this corporation, which were adopted by the stockholders of this corporation
on April 21, 1987 as aforesaid, are as follows:

      (a) Article 3 was amended to read as follows:

      "3. STOCK:

      SECTION 1. Capital Stock. The corporation shall have the authority to
issue 500,000,000 shares of Common Stock, without par value, and 50,000,000
shares of Preferred Stock, without par value.

      SECTION 2. Preferred Stock. The Board of Directors shall have authority to
issue the shares of Preferred Stock from time to time on such terms as it may
determine, and to divide the Preferred Stock into one or more classes or series
and in connection with the creation of any such class or series to fix, by
resolution or resolutions providing for the issue thereof, the designation, the
number of shares, and the relative rights, preferences and limitations thereof,
to the full extent now or hereafter permitted by law."

      (b) Article 8 was amended to read as follows:

      "8. INDEMNIFICATION: LIMITATION OF LIABILITY:

      SECTION 1. Indemnification. The corporation shall indemnify to the full
extent from time to time permitted by law any person made, or threatened to be
made, a party to any pending, threatened or completed civil, criminal,
administrative or arbitrative action, suit or proceeding and any appeal therein
(and any inquiry or investigation which could lead to such action, suit or
proceeding) by reason of the fact that he is or was a director, officer or
employee of the corporation or serves or served any other enterprise as a
director, officer or employee at the request of the corporation. Such right of
indemnification shall inure to the benefit of the legal representative of any
such person.

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      SECTION 2. Limitation of Liability. To the full extent from time to time
permitted by law, directors and officers of the corporation shall not be
personally liable to the corporation or its shareholders for damages for breach
of any duty owed to the corporation or its shareholders. No amendment or repeal
of this provision shall adversely affect any right or protection of a director
or officer of the corporation existing at the time of such amendment or repeal."

      (c) New Articles 9, 10 and 11 were added, existing Articles 9 and 10 were
deleted, and existing Articles 11 through 14 were renumbered as Articles 12
through 15. New Articles 9, 10 and 11 read as follows:

      "9. CERTAIN BUSINESS COMBINATIONS:

      SECTION 1. Vote Required for Certain Business Combinations. In addition to
any affirmative vote required by law and except as otherwise expressly provided
in Section 2 of this Article 9:

            (a) any merger or consolidation of the corporation or any Subsidiary
      (hereinafter defined) with (i) any Interested Shareholder (hereinafter
      defined) or (ii) any other corporation (whether or not itself an
      Interested Shareholder) which is, or after such merger or consolidation
      would be, an Affiliate (hereinafter defined) of an Interested Shareholder;
      or

            (b) any sale, lease, exchange, mortgage, pledge, transfer or other
      disposition (in one transaction or a series of transactions) to or with
      any Interested Shareholder or any Affiliate of any Interested Shareholder
      of any assets of the corporation or any Subsidiary having an aggregate
      Fair Market Value (hereinafter defined) of $25,000,000 or more; or

            (c) the issuance or transfer by the corporation or any Subsidiary
      (in one transaction or a series of transactions) of any securities of the
      corporation or any Subsidiary to any Interested Shareholder or Affiliate
      of any Interested Shareholder in exchange for cash, securities or other
      property (or a combination thereof) having an aggregate Fair Market Value
      of $25,000,000 or more; or

            (d) the adoption of any plan or proposal for the liquidation or
      dissolution of the corporation proposed by or on behalf of any Interested
      Shareholder or any Affiliate of any Interested Shareholder; or

            (e) any reclassification of securities (including any reverse stock
      split), recapitalization of the corporation, any merger or consolidation
      of the corporation with any of its Subsidiaries or any other transaction
      (whether or not with or into or otherwise involving an Interested
      Shareholder) which has the effect, directly or indirectly, of increasing
      the proportionate share of the outstanding shares of any class of equity
      or convertible securities of the corporation or any Subsidiary which is
      directly or indirectly owned by any Interested Shareholder or any
      Affiliate of any Interested Shareholder;

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      shall require prior approval by the affirmative vote of 80% of the votes
      which the holders of the then outstanding shares of capital stock of the
      corporation are entitled to vote in the election of directors (the "Voting
      Stock"), voting together as a single class (each share of the Voting Stock
      having a number of votes duly fixed by the Board of Directors pursuant to
      Article 3 of the Certificate of Incorporation or provided by the By-Laws).
      Such affirmative vote shall be required notwithstanding the fact that no
      vote may be required, or that a lesser percentage may be specified, by law
      or in any agreement with any national securities exchange or otherwise.
      The term "Business Combination" as used in this Article 9 shall mean any
      transaction which is referred to in any one or more of paragraphs (a)
      through (e) of this Section 1.

      SECTION 2. Exceptions to 80% Vote. The provisions of Section 1 of this
Article 9 shall not be applicable to any particular Business Combination (and
such Business Combination shall require only such affirmative vote which may be
required by law or otherwise) if all of the conditions specified in either of
the following paragraphs (a) or (b) are met:

            (a) The Business Combination shall have been approved by majority
      vote of the Disinterested Directors (hereinafter defined).

            (b) All of the following conditions shall have been met:

                  (i) The aggregate amount of the cash and the Fair Market
            Value, as of the date of the consummation of the Business
            Combination, of consideration other than cash to be received per
            share by holders of Common Stock in such Business Combination shall
            be at least equal to the higher of:

                        (1) if applicable, the highest per share price
                  (including any brokerage commissions, transfer taxes and
                  soliciting dealers' fees) paid by the Interested Shareholder
                  for any shares of Common Stock acquired by it (x) within the
                  two-year period immediately prior to the first public
                  announcement of the proposal of the Business Combination (the
                  "Announcement Date") or (y) in the transaction in which it
                  became an Interested Shareholder, whichever is higher; or

                        (2) the Fair Market Value per share of Common Stock on
                  the Announcement Date or on the date (the "Determination
                  Date") on which the Interested Shareholder became an
                  Interested Shareholder, whichever is higher.

                  (ii) The aggregate amount of the cash and the Fair Market
            Value, as of the date of the consummation of the Business
            Combination, of consideration other than cash to be received per
            share by holders of shares of any class or series of outstanding
            Voting Stock other than Common Stock shall be at least equal to the
            highest of the following (it being intended that the requirements of
            this paragraph (b)(ii) shall be

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            met with respect to every such class or series whether or not the
            Interested Shareholder has previously acquired any shares thereof):

                        (1) if applicable, the highest per share price
                  (including any brokerage commissions, transfer taxes and
                  soliciting dealers' fees) paid by the Interested Shareholder
                  for any shares of such class or series acquired by it (x)
                  within the two-year period immediately prior to the
                  Announcement Date or (y) in the transaction in which it became
                  an Interested Shareholder, whichever is higher; or

                        (2) if applicable, the highest preferential amount per
                  share to which the holders of shares of such class or series
                  are entitled in the event of any voluntary or involuntary
                  liquidation, dissolution or winding up of the corporation; or

                        (3) the Fair Market Value per share of such class or
                  series on the Announcement Date or on the Determination Date,
                  whichever is higher.

                  (iii) The consideration to be received by holders of a
            particular class or series of outstanding Voting Stock (including
            Common Stock) shall be in cash or in the same form as the Interested
            Shareholder has previously paid for shares of such class or series
            of Voting Stock. If the Interested Shareholder has paid for shares
            of any class or series of Voting Stock with varying forms of
            considerations, the form of consideration for such class or series
            shall be either cash or the form used to acquire the largest number
            of shares of such class or series previously acquired by it. The
            price determined in accordance with paragraphs (b)(i) and (b)(ii) of
            this Section 2 shall be subject to appropriate adjustment in the
            event of any stock dividend, stock split, combination of shares or
            similar event.

                  (iv) After such Interested Shareholder has become an
            Interested Shareholder and prior to the consummation of such
            Business Combination: (1) except as approved by a majority of the
            Disinterested Directors, there shall have been no failure to declare
            and pay at the regular date therefor any dividends (whether or not
            cumulative) on any outstanding series of Preferred Stock: (2) there
            shall have been (x) no reduction in the annual rate of dividends
            paid on the Common Stock (except as necessary to reflect any
            subdivisions of the Common Stock), except as approved by a majority
            of the Disinterested Directors, and (y) an increase in such annual
            rate of dividends as necessary to reflect any reclassification
            (including any reverse stock split), recapitalization,
            reorganization or any similar transaction which has the effect of
            reducing the number of outstanding shares of Common Stock, unless
            the failure to so increase such annual rate is approved by a
            majority of the Disinterested Directors; and (3) such Interested
            Shareholder shall have not become the beneficial owner of any
            additional shares of Voting Stock except as part of the transaction
            which results in such Interested Shareholder becoming an Interested
            Shareholder.

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                  (v) After such Interested Shareholder has become an Interested
            Shareholder, such Interested Shareholder shall not have received the
            benefit, directly or indirectly (except proportionately as a
            shareholder), of any loans, advances, guarantees, pledges or other
            financial assistance, or any tax credits or other tax advantages,
            provided by the corporation, whether in anticipation of or in
            connection with such Business Combination or otherwise.

                  (vi) A proxy or information statement describing the proposed
            Business Combination and complying with the requirements of the
            Securities Exchange Act of 1934 and the rules and regulations
            thereunder (or any subsequent provisions replacing such act, rules
            or regulations) shall be mailed to shareholders of the corporation
            at least 30 days prior to the consummation of such Business
            Combination (whether or not such proxy or information statement is
            required to be mailed pursuant to such act, rules and regulations or
            subsequent provisions).

      SECTION 3. Certain Definitions. For the purposes of this Article 9:

            (a) "Person" shall mean any individual, firm, corporation or other
      entity.

            (b) "Interested Shareholder" shall mean any person (other than the
      corporation or any Subsidiary) who or which:

                  (i) is the beneficial owner, directly or indirectly, of shares
            having 10% or more of the votes of the then outstanding Voting
            Stock; or

                  (ii) is an Affiliate of the corporation and at any time within
            the two-year period immediately prior to the date in question was
            the beneficial owner, directly or indirectly, of shares having 10%
            or more of the votes of the then outstanding Voting Stock; or

                  (iii) is an assignee of or has otherwise succeeded to any
            shares of Voting Stock which were at any time within the two-year
            period immediately prior to the date in question beneficially owned
            by any Interested Shareholder, if such assignment or succession
            shall have occurred in the course of a transaction or series of
            transactions not involving a public offering within the meaning of
            the Securities Act of 1933.

            (c) A person shall be a "beneficial owner" of any Voting Stock:

                  (i) which such person, or any of its Affiliates or Associates
            (as hereinafter defined), beneficially owns, directly or indirectly;
            or

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                  (ii) which such person, or any of its Affiliates or
            Associates, has (1) the right to acquire (whether such right is
            exercisable immediately or only after the passage of time) pursuant
            to any agreement, arrangement or understanding or upon the exercise
            of conversion rights, exchange rights, warrants or options or
            otherwise, or (2) the right to vote pursuant to any agreement,
            arrangement or understanding; or

                  (iii) which is beneficially owned, directly or indirectly, by
            any other person with which such person or any of its Affiliates or
            Associates has any agreement, arrangement or understanding for the
            purpose of acquiring, holding, voting or disposing of any shares of
            Voting Stock.

            For the purposes of determining whether a person is an Interested
      Shareholder, the number of shares of Voting Stock deemed to be outstanding
      shall include shares deemed owned through application of this paragraph
      (c) of Section 3 but shall not include any other shares of Voting Stock
      which may be issuable pursuant to any agreement, arrangement or
      understanding, or upon exercise of conversion rights, warrants or options
      or otherwise.

            (d) "Affiliate" or "Associate" shall have the respective meanings
      given for such terms in Rule 12b-2 of the General Rules and Regulations
      under the Securities Exchange Act of 1934, as in effect on January 1,
      1987.

            (e) "Subsidiary" shall mean any corporation of which a majority of
      the voting shares is owned, directly or indirectly, by the corporation.

            (f) "Disinterested Director" shall mean any member of the Board of
      Directors of the corporation who is not an Affiliate, Associate or
      representative of the Interested Shareholder and was a member of the Board
      of Directors prior to the time that the Interested Shareholder became an
      Interested Shareholder, and any successor of a Disinterested Director who
      is not an Affiliate, Associate or representative of the Interested
      Shareholder and was recommended or elected to succeed a Disinterested
      Director by a majority of Disinterested Directors then on the Board of
      Directors.

            (g) "Fair Market Value" shall mean:

                  (i) in the case of stock, the highest closing sale price
            during the 30-day period immediately preceding the date in question
            on the Composite Tape for New York Stock Exchange-Listed Stocks, or,
            if such stock is not quoted on the Composite Tape on the New York
            Stock Exchange, or, if such stock is not listed on such exchange, on
            the principal United States securities exchange registered under the
            Securities Exchange Act of 1934 on which such stock is listed, or,
            if such stock is not listed on any such exchange, the highest
            closing bid quotation with respect to a share of such stock during
            the 30-day

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            period preceding the date in question on the National Asssociation
            of Securities Dealers, Inc. Automated Quotations System or any
            system then in use, or if no such quotations are available, the fair
            market value on the date in question as determined by a majority of
            the Disinterested Directors in good faith; or

                  (ii) in the case of property other than stock, the fair market
            value of such property on the date in question as determined by a
            majority of the Disinterested Directors in good faith.

            (h) In the event of any Business Combination in which the
      corporation survives, the phrase "consideration other than cash to be
      received" as used in paragraphs (b)(i) and (ii) of Section 2 of this
      Article 9 shall include the shares of Common Stock and/or the shares of
      any other class of outstanding Voting Stock retained by the holders of
      such shares.

      SECTION 4. Powers of the Board of Directors. The Board of Directors shall
have the power and duty, by majority vote of the Disinterested Directors, to
determine for the purposes of this Article 9, on the basis of information known
to them after reasonable inquiry, (a) whether a person is an Interested
Shareholder, (b) the number of shares of Voting Stock beneficially owned by any
person, (c) whether a person is an Affiliate or Associate of another and (d)
whether the assets which are the subject of any Business Combination have, or
the consideration to be received for the issuance or transfer of securities by
the corporation or any Subsidiary in any Business Combination has, an aggregate
Fair Market Value of $25,000,000 or more. A majority of the Disinterested
Directors shall also have the power to interpret all of the other terms and
provisions of this Article 9 and to make any other factual determinations in
regard to the applicability of this Article 9. Any interpretations or
determination made in good faith by majority vote of the Disinterested Directors
with regard to application of this Article 9 on the basis of such information as
was then available for such purpose shall be conclusive and binding on the
corporation and on all of its shareholders, including any Interested
Shareholder.

      SECTION 5. No Effect on Fiduciary Obligations of Interested Shareholders.
Nothing contained in this Article 9 shall be construed to relieve any Interested
Shareholder from any fiduciary obligations imposed by law.

      SECTION 6. Severability. In the event any provision (or part thereof) of
this Article 9 should be determined to be invalid, prohibited or unenforceable
for any reason, the remaining provisions, and parts thereof, shall remain in
full force and effect and enforceable against the corporation and its
shareholders, including any Interested Shareholder, to the fullest extent
permitted by law.

      SECTION 7. Amendment. Notwithstanding any other provisions of this
Certificate of Incorporation, the By-Laws of the corporation or applicable law
the affirmative vote of 80% of the votes of the then outstanding Voting Stock
voting together as a single class, shall be required (a) to amend, modify or
repeal this Article 9, (b) adopt any provision to this Certificate of
Incorporation of By-Laws which is inconsistent with this Article 9, or (c) prior
to the fixing by the

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Board of Directors of any right or preference of any series of Preferred Stock
which is inconsistent with the provisions of this Article 9."

      "10. BOARD OF DIRECTORS:

      SECTION 1. Number, election and terms. Except as otherwise fixed by or
pursuant to the provisions of Article 3 hereof relating to the rights of the
holders of any class or series of stock having a preference over the Common
Stock as to dividends or upon liquidation to elect additional directors under
specified circumstances, the number of the directors of the corporation shall be
fixed from time to time by or pursuant to the By-Laws of the corporation. The
directors, other than those who may be elected by the holders of any class of
series of stock having a preference over the Common Stock as to dividends or
upon liquidation, shall be classified, with respect to the time for which they
severally hold office, into three classes, as nearly equal in number as
possible, as shall be provided in the manner specified in the By-Laws of the
corporation, one class to be originally elected for a term expiring at the
annual meeting of stockholders to be held in 1988, another class to be
originally elected for a term expiring at the annual meeting of stockholders to
be held in 1989, and another class to be originally elected for a term expiring
at the annual meeting of stockholders to be held in 1990, with the directors in
each class to hold office until their respective successors are elected and
qualified. At each annual meeting of the stockholders of the corporation, the
successors of the class of directors whose term expires at that meeting shall be
elected to hold office for a term expiring at the annual meeting of stockholders
held in the third year following the year of their election and until their
respective successors are elected and qualified.

      SECTION 2. Stockholder nomination of director candidates. Advance notice
of shareholder nominations for the election of directors shall be given in the
manner provided in the By-Laws of the corporation.

      SECTION 3. Newly created directorships and vacancies. Except as otherwise
provided for or fixed by or pursuant to the provisions of Article 3 hereof
relating to the rights of the holders of any class or series of stock having a
preference over the Common Stock as to dividends or upon liquidation to elect
directors under specified circumstances, newly created directorships resulting
from any increase in the number of directors and any vacancies on the Board of
Directors resulting from death, resignation, disqualification, removal or other
cause shall be filled by the affirmative vote of a majority of the remaining
directors then in office, even though less than a quorum of the Board of
Directors. Any director elected in accordance with the preceding sentence shall
hold office until the next succeeding annual meeting of shareholders and until
such director's successor, who shall be elected for the remainder of the full
term of the class of directors in which the new directorship was created or the
vacancy occurred, shall have been elected and qualified. No decrease in the
number of directors constituting the Board of Directors shall shorten the term
of any incumbent director.

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      SECTION 4. Removal and Suspension, Subject to the rights of any class or
series of stock having a preference over the Common Stock as to dividends or
upon liquidation to elect directors under specified circumstances, any director
may be removed from office without cause only by the affirmative vote of the
holders of 80% of the combined voting power of the then outstanding shares of
stock entitled to vote generally in the election of directors, voting together
as a single class. The Board of Directors, by the affirmative vote of a majority
of the directors in office, may remove a director or directors for cause where,
in the judgment of such majority, the continuation of the director or directors
in office would be harmful to the corporation and may suspend the director or
directors for a reasonable period pending final determination that cause exists
for such removal.

      SECTION 5. Amendment, repeal, etc. Notwithstanding anything in this
Certificate of Incorporation to the contrary, the affirmative vote of the
holders of at least 80% of the voting power of all shares of the corporation
entitled to vote generally in the election of directors, voting together as a
single class, shall be required to alter, amend, adopt any provision
inconsistent with or repeal this Article 10."

      "11. BY-LAW AMENDMENTS:

      The Board of Directors shall have power to make, alter, amend and repeal
the By-Laws of the corporation (except so far as the By-Laws of the corporation
adopted by the shareholders shall otherwise provide). Any By-Laws made by the
Directors under the powers conferred hereby may be altered, amended or repealed
by the directors or by the shareholders. Notwithstanding the foregoing and
anything contained in this Certificate of Incorporation to the contrary, Article
I, Section 1; Article IX, Section 9; and Article XVI of the By-Laws shall not be
altered, amended or repealed and no provision inconsistent therewith shall be
adopted without the affirmative vote of the holders of at least 80% of the
voting power of all the shares of the corporation entitled to vote generally in
the election of directors, voting together as a single class. Notwithstanding
anything contained in this Certificate of Incorporation to the contrary, the
affirmative vote of the holders of at least 80% of the voting power of all the
shares of the corporation entitled to vote generally in the election of
directors, voting together as a single class, shall be required to alter, amend,
or adopt any provision inconsistent with or repeal this Article 11."

      IN WITNESS WHEREOF, said Public Service Enterprise Group Incorporated has
made this Certificate this 23rd day of April, 1987.

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                  PUBLIC SERVICE ENTERPRISE GROUP INCORPORATED

                               By E. JAMES FERLAND

                                E. James Ferland

                        Chairman of the Board, President
                           and Chief Executive Officer

Attest:

D.S. POCIUS

Assistant Secretary

(Corporate Seal)

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