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                                                                     EXHIBIT 3.1


                           SECOND AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                             METAL MANAGEMENT, INC.
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         This Second Amended and Restated Certificate of Incorporation of Metal
Management, Inc., a Delaware corporation (the "Corporation"), was duly
authorized and adopted in accordance with the provisions of Section 303 of The
General Corporation Law of the State of Delaware.

         1. The name under which the Corporation was originally incorporated on
June 5, 1986 was General Parametrics Corporation.

         2. The text of the Corporation's certificate of incorporation is hereby
amended and restated in its entirety to read as set forth below:

                           SECOND AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                             METAL MANAGEMENT, INC.
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FIRST: The name of the corporation is Metal Management, Inc.

SECOND: The address of the Corporation's registered office in the State of
Delaware is 1209 Orange Street, in the City of Wilmington, County of New Castle,
Delaware 19801; and the name of the registered agent at such address is The
Corporation Trust Company.

THIRD: The nature of the business or purposes to be conducted or promoted by the
Corporation is to engage in any lawful act or activity for which corporations
may be organized under The General Corporation Law of Delaware.

FOURTH: (a) The Corporation is authorized to issue two classes of shares to be
designated, respectively, common stock, par value $.01 per share ("Common
Stock") and preferred stock, par value $.01 per share ("Preferred Stock"). The
number of shares of Common Stock authorized to be issued is Fifty Million
(50,000,000), of which Ten Million (10,000,000) shares of Common Stock will be
issued upon the effective date of the Corporation's First Amended Joint Plan of
Reorganization, dated May 4, 2001, as amended (the "Plan"), and the number of
shares of Preferred Stock authorized to be issued is Two Million (2,000,000).

         The Board of Directors of the Corporation is authorized, subject to
limitations prescribed by law and the Plan, to provide for the issuance of the
Preferred Stock in one or more series, and by filing a certificate pursuant to
the applicable law of the State of Delaware, to: (i) establish from time to time
the number of shares to be included in each such series; (ii) fix the voting
powers, designations, powers, preferences and relative, participating, optional
or other rights of the shares of each such series and the qualifications,
limitations or restrictions thereof, including but not limited to the fixing or
alteration of the dividend rights, dividend rate,





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conversion rights, conversion rate, voting rights, rights and terms of
redemption (including sinking fund provisions), the redemption price or prices,
and the liquidation preferences of any wholly unissued series of shares of
Preferred Stock; and (iii) increase or decrease the number of shares of any
series subsequent to the issue of shares of that series, but not below the
number of shares of such series then outstanding. In case the number of shares
of any series shall be so decreased, the number of shares constituting such
decrease shall resume the status which they had prior to the adoption of the
resolution originally fixing the number of shares of such series.

         (b) The Corporation shall not issue any non-voting equity securities.

FIFTH: Any action required or permitted to be taken by the stockholders of the
Corporation must be effected at a duly called annual or special meeting of
stockholders and may not be effected by a consent in writing by any such
stockholders.

SIXTH: The Corporation is to have perpetual existence.

SEVENTH: In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors is expressly authorized to make, alter, amend or
repeal the By-Laws of the Corporation.

EIGHTH: The number of directors which will constitute the whole Board of
Directors of the Corporation shall be as specified in the By-Laws of the
Corporation.

NINTH: The election of directors need not be by written ballot unless the
By-Laws of the Corporation shall so provide.

TENTH: In voting for the election of directors of the Corporation, holders of
stock shall not have the right to accumulate their votes.

ELEVENTH: Meetings of stockholders may be held within or without the State of
Delaware, as the By-Laws may provide. The books of the Corporation may be kept
(subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the By-Laws of the Corporation.

TWELFTH: A director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived an improper
personal benefit.

THIRTEENTH: (a) The Corporation shall indemnify any person who was or is a party
or is threatened to be made a party to any threatened, pending, or completed
action, suit or proceeding, whether civil, criminal, administrative, or
investigative (other than an action by or in the right of the corporation) by
reason of the fact that he is or was a director, officer, employee or agent of
the Corporation, or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise, against expenses (including attorneys'
fees), judgments, fines and amounts paid in



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settlement actually and reasonably incurred by him in connection with such
action, suit or proceeding if he acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the
Corporation, and, with respect to any criminal action or proceeding, has no
reasonable cause to believe his conduct was unlawful. The termination of any
action, suit, or proceeding by judgment, order, settlement, conviction or upon a
plea of nolo contendere or its equivalent, shall not, of itself, create a
presumption that the person did not act in good faith and in a manner which he
reasonably believed to be in or not opposed to the best interest of the
Corporation, and, with respect to any criminal action or proceeding, has
reasonable cause to believe that his conduct was unlawful.

         (b) The Corporation shall indemnify any person who was or is a party or
is threatened to be made a party to any threatened, pending or completed action
or suit by or in the right of the Corporation to procure a judgment in its favor
by reason of the fact that he is or was a director, officer, employee or agent
of the Corporation, or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise against expenses (including attorneys' fees)
actually and reasonably incurred by him in connection with the defense or
settlement of such action or suit if he acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the
Corporation and except that no indemnification shall be made in respect of any
claim, issue, or matter as to which such person shall have been adjudged to be
liable to the Corporation unless and only to the extent that the Delaware Court
of Chancery or the court in which such action or suit was brought shall
determine upon application that, despite the adjudication of liability but in
view of all the circumstances of the case, such person is fairly and reasonably
entitled to indemnity for such expenses which the Court of Chancery or such
other court shall deem proper.

         (c) To the extent that a director, officer, employee or agent of the
Corporation has been successful on the merits or otherwise in defense of any
action, suit or proceeding referred to in subparagraphs (a) and (b), or in
defense of any claim, issue or matter therein, he shall be indemnified against
expenses (including attorneys' fees) actually and reasonably incurred by him in
connection therewith.

         (d) Any indemnification under subparagraphs (a) and (b) (unless ordered
by a court) shall be made by the Corporation only as authorized in the specific
case upon a determination that indemnification of the director, officer,
employee or agent is proper in the circumstances because he has met the
applicable standard of conduct set forth in subparagraphs (a) and (b). Such
determination shall be made (1) by the Board of Directors by a majority vote of
a quorum consisting of directors who were not parties to such action, suit or
proceeding, or (2) if such a quorum is not obtainable, or, even if obtainable, a
quorum of disinterested directors so directs, by independent legal counsel in a
written opinion, or (3) by the stockholders.

         (e) Expenses incurred in defending a civil or criminal action, suit or
proceeding shall be paid by the Corporation in advance of the final disposition
of such action, suit or proceeding as authorized by the Board of Directors upon
receipt of an undertaking by or on behalf of the director, officer, employee or
agent to repay such amount if it shall ultimately be determined that he is not
entitled to be indemnified by the Corporation as authorized in this Article 13.



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         (f) The indemnification and advancement of expenses provided by, or
granted pursuant to, the other subparagraphs of this Article shall not be deemed
exclusive of any other rights to which those seeking indemnification or
advancement of expenses may be entitled under any by-law, agreement, vote of
stockholders or disinterested directors or otherwise, both as to action in his
official capacity and as to action in another capacity while holding such
office.

         (g) The Corporation shall have the power to purchase and maintain
insurance on behalf of any person who is or was a director, officer, employee or
agent of the Corporation, or is or was serving at the request of the Corporation
as a director, officer, employee or agent of another corporation, partnership,
joint venture, trust or other enterprise against any liability asserted against
him and incurred by him in any such capacity, or arising out of his status as
such, whether or not the Corporation would have the power to indemnify him
against such liability under the provisions of this Article 13.

         (h) For purposes of this Article 13, references to "the Corporation"
shall include, in addition to the resulting corporation, any constituent
corporation (including any constituent of a constituent) absorbed in a
consolidation or merger which, if its separate existence had continued, would
have had power and authority to indemnify its directors, officers, and employees
or agents, so that any person who is or was a director, officer, employee or
agent of such constituent corporation, or is or was serving at the request of
such constituent corporation as a director, officer, employee or agent of
another corporation, partnership, joint venture, trust or other enterprise,
shall stand in the same position under the provisions of this Article 13 with
respect to the resulting or surviving corporation as he would have with respect
to such constituent corporation if its separate existence had continued.

         (i) For purposes of this Article 13, references to "other enterprises"
shall include employee benefit plans; references to "fines" shall include any
excise taxes assessed on a person with respect to an employee benefit plan; and
references to "serving at the request of the Corporation" shall include any
service as a director, officer, employee or agent of the Corporation which
imposes duties on, or involves services by, such director, officer, employee or
agent with respect to an employee benefit plan, its participants or
beneficiaries; and a person who acted in good faith and in a manner he
reasonably believed to be in the interest of the participants and beneficiaries
of an employee benefit plan shall be deemed to have acted in a manner "not
opposed to the best interests of the corporation" as referred to in this Article
13.

         (j) The indemnification and advancement of expenses provided by, or
granted pursuant to, this Article 13 shall, unless otherwise provided when
authorized or ratified, continue as to a person who has ceased to be a director,
officer, employee or agent and shall inure to the benefit of the heirs,
executors and administrators of such a person.

FOURTEENTH: The Corporation reserves the right to amend, alter, change or repeal
any provision contained in this Second Amended and Restated Certificate of
Incorporation, in the manner now or hereafter prescribed by statute, and all
rights conferred upon stockholders herein are granted subject to this
reservation.


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         IN WITNESS WHEREOF, the Corporation has caused this Second Amended and
Restated Certificate of Incorporation to be signed by Albert A. Cozzi, its
Chairman of the Board and Chief Executive Officer, who does make this
certificate and declare and certify under penalty of perjury that this is the
act and deed of the Corporation, and that the facts stated herein are true, and
accordingly has set his hand hereto this 29th day of June, 2001.

                                            METAL MANAGEMENT, INC.



                                            By:  /s/ Albert A. Cozzi
                                               ---------------------------------
                                            Name:  Albert A. Cozzi
                                            Title: Chairman of the Board
                                                   and Chief Executive Officer





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