EXHIBIT 3.84

BY-LAWS

OF

HAZY RIDGE COAL COMPANY

ARTICLE I. OFFICES

The principal offices of the Corporation shall be located in the City of Pettus. The Corporation may have such other offices, either within or without the State of West Virginia, as the Board of Directors may designate or as the business of the Corporation may require from time to time.

ARTICLE II. SHAREHOLDERS

Section 1. Annual Meeting. The annual meeting of the shareholders shall be held on the last Wednesday in the month of May, in each year, at the hour of 1:15 P. M., local time, beginning in 1995, or at such other time on such other day within such month as shall be fixed by the Board of Directors, for the purpose of electing directors and for the transaction of such other business as may come before the meeting. If the day fixed for the annual meeting shall be a legal holiday in the State of the principal office of the Corporation, such meeting shall be held on the next succeeding business day.

Section 2. Special Meetings. Special meetings of the shareholders, for any purpose or purposes, may be called by the Chairman of the Board, if any, President, Secretary, or by the Board of Directors, and shall be called by the President at the request of the holders of not less than one-tenth of all outstanding shares of the Corporation entitled to vote at the meeting.

Section 3. Place of Meeting. The Board of Directors may designate any place, either within or without the State of West Virginia, as the place of meeting for any annual meeting or for any special meeting called by the Board of Directors. If no designation is made, or if a special meeting be otherwise called, the place of meeting shall be the principal office of the Corporation.

Section 4. Notice of Meeting. Written notice stating the place, day and hour of the meeting, and in case of a special meeting, the purpose or purposes for which the meeting is called, shall be delivered not less than ten nor more than fifty days before the date of the meeting, either personally or by mail, by, or at the direction of the Chairman of the Board, President, Secretary or the officer or other persons calling the meeting, to each shareholder of record entitled to vote at such meeting. If mailed, such notice shall be deemed to be delivered when deposited in the United States mail, addressed to the shareholder at his address as it appears on the stock transfer books of the Corporation, with postage thereon prepaid.

Section 5. Closing of Transfer Books or Fixing of Record Date. For the purposes of determining shareholders entitled to notice of or vote at any meeting of shareholders or any adjournment thereof, or shareholders entitled to receive payment of any dividend, or in order to make a determination of shareholders for any other proper purpose, the Board of Directors of the Corporation may provide that the stock transfer books shall be closed for a stated period but not to exceed, in any case, fifty days. If the stock transfer books shall be closed for the purpose of determining shareholders entitled to notice of or to vote at a meeting of shareholders, such books shall be closed for at least ten days immediately preceding such meeting. In lieu of closing the stock transfer books, the Board of Directors may fix in advance a date as the record date for any such determination of shareholders, such date in any case to be not more than fifty days and, in case of a meeting of shareholders, not less man ten days prior to the date on which the particular action, requiring such determination of shareholders, is to be taken. If the stock transfer books are not closed and no record date is fixed for the determination of shareholders entitled to notice or to vote at a meeting of shareholders, or shareholders entitled to receive payment of a dividend, the date on which notice of the meeting is mailed or the date on which the resolution of the Board of Directors declaring such dividend is adopted, as the case may be, shall be the record date for such determination of shareholders. When a determination of shareholders entitled to vote at any meeting of shareholders has been made as provided in this section, such determination shall apply to any adjournment thereof.

Section 6. Voting Record. The officer or agent having charge of the stock transfer books for shares of the Corporation shall make a complete record of the shareholders entitled to vote at each meeting of shareholders or any adjournment thereof, arranged in alphabetical order, with the address of and the number of shares held by each. Such record shall be produced and kept open at the time and place of the meeting and shall be subject to the inspection of any shareholder during the whole time of the meeting for the purpose thereof.

Section 7. Quorum. A majority of the outstanding shares of the Corporation entitled to vote, represented in person or by proxy, shall constitute a quorum at a meeting of shareholders. If less than a majority of the outstanding shares are represented at a meeting, a majority of the shares so represented may adjourn the meeting from time to time without further notice. At such adjourned meeting at which a quorum shall be present or represented, any business may be transacted which might have been transacted at the meeting as originally noticed. The shareholders present at a duly organized meeting may continue to transact business until adjournment, notwithstanding the withdrawal of enough shareholders to leave less than a quorum.

Section 8. Proxies. At all meetings of shareholders, a shareholder may vote in person or by proxy executed in writing by the shareholder or by his duly authorized attorney-in-fact. Such proxy shall be filed with the Secretary of the Corporation before or at the time of the meeting. No proxy shall be valid after eleven months from the date of its execution, unless otherwise provided in the proxy.

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Section 9. Voting of Shares. Subject to the provisions of Section 12 of this Article II, each outstanding share entitled to vote shall be entitled to one vote upon each matter submitted to a vote at a meeting of shareholders.

Section 10. Voting of Shares by Certain Holders. Shares standing in the name of another corporation may be voted by such officer, agent or proxy as the by-laws of such corporation may prescribe, or, in the absence of such provision, as the Board of Directors of such other corporation may determine.

Shares held by an administrator, executor, guardian, committee, curator, or conservator may be voted by him, either in person or by proxy, without a transfer of such shares into his name. Shares standing in the name of a trustee may be voted by him either in person or by proxy, but no trustee shall be entitled to vote shares held by him without a transfer of such shares into his name.

Shares standing in the name of a receiver may be voted by such receiver, and shares held by or under the control of a receiver may be voted by such receiver without the transfer thereof into his name if authority so to do be contained in an appropriate order of the court by which such receiver was appointed.

A shareholder whose shares are pledged shall be entitled to vote such shares until the shares have been transferred into the name of the pledgee, and thereafter the pledgee shall be entitled to vote the shares so transferred.

Neither treasury shares of its own stock held by the Corporation, nor shares held by another corporation if a majority of the shares entitled to vote for the election of directors of such other corporation are held by the Corporation, shall be voted at any meeting or counted in determining the total number of outstanding shares at any given time for purposes of any meeting.

Section 11. Informal Action by Shareholders. Any action required or permitted to be taken at a meeting of the shareholders may be taken without a meeting if a consent in writing, setting forth the action so taken, shall be signed by all of the shareholders entitled to vote with respect to the subject matter thereof.

Section 12. Cumulative Voting. At each election for directors every shareholder entitled to vote at such election shall have the right to vote, in person or by proxy, the number of shares owned by him for as many persons as there are directors to be elected and for whose election he has a right to vote, or to cumulate his votes by giving one candidate as many votes as the number of such directors multiplied by the number of his shares shall equal, or by distributing such votes on the same principle among any number of such candidates.

ARTICLE III. BOARD OF DIRECTORS

Section 1. General Powers. The business and affairs of the Corporation shall be managed by its Board of Directors.

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Section 2. Number, Tenure and Qualifications. The number of directors of the Corporation shall be one or more. Each director shall hold office until the next annual meeting of shareholders and until successor shall have been elected and qualified. Directors need not be residents of the State of West Virginia, or shareholders of the Corporation.

Section 3. Regular Meetings. A regular meeting of the Board of Directors shall be held without other notice than this by-law immediately after, and at the same place as, the annual meeting of shareholders. The Board of Directors may provide, by resolution, the time and place, either within or without the State of West Virginia, for the holding of additional regular meetings without other notice than such resolution.

Section 4. Special Meeting. Special meeting of the Board of Directors may be called by or at the request of the Chairman of the Board, if any, the President or any two directors. The person or persons authorized to call special meetings of the Board of Directors may fix any place, either within or without the Stale of West Virginia, as the place for holding any special meeting of the Board of Directors called by them.

Section 5. Notice. Notice of any special meeting shall be given at least three days previously thereto by written notice delivered personally or mailed to each director at his business address, or by telegram. If mailed at least five days prior to the date of meeting, such notice shall be deemed to be delivered when deposited in the United States mail, so addressed, with postage thereon prepaid. If notice be given by telegram, such notice shall be deemed to be delivered when the telegram is delivered to the telegraph company. Any director may waive notice of any meeting. The attendance of a director at a meeting shall constitute a waiver of notice of such meeting, except where a director attends a meeting for express purpose of objecting to the transaction of any business because the meeting is not lawfully called or convened. Neither the business to be transacted at, nor the purpose of, any regular or special meeting of the Board of Directors need be specified in the notice or waiver of notice of such meeting, except as otherwise provided by statute.

Section 6. Quorum. A majority of the number of directors fixed by Section 2 of this Article Ill shall constitute a quorum for the transaction of business at any meeting of the Board of Directors, but if less than such majority is present at a meeting a majority of the directors present may adjourn the meeting from time to time without further notice.

Section 7. Manner of Acting. The act of the majority of the directors present at a meeting at which a quorum is present shall be the act of the Board of Directors.

Section 8. Action Without a Meeting. Any action required or permitted to be taken by the Board of Directors at a meeting may be taken without a meeting if a consent in writing, setting forth the action so taken, shall be signed by all of the directors.

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Section 9. Vacancies.

(a) If a vacancy occurs on the Board of Directors, including a vacancy resulting from an increase in the number of directors:

(1) the shareholder may fill the vacancy;

(2) the board of directors may fill the vacancy; or

(3) if the directors remaining in office constitute fewer than a quorum of the board, they may fill the vacancy by the affirmative vote of a majority of all the directors remaining in office.

(b) If the vacant office was held by a director elected by a voting group of shareholders, only the holders of shares of that voting group are entitled to vote to fill the vacancy if it is filled by the shareholders.

(c) A vacancy that will occur at a specific later date (by reason of a resignation effective at a later date under section 8.07(b) of the Model Business Corporation Act [1984] or otherwise) may be filled before the vacancy occurs but the new director may not take office until the vacancy occurs.

Section 10. Compensation. By resolution of the Board of Directors, each director may be paid his expenses, if any, of attendance at each meeting of the Board of Directors, or committee thereof, and may be paid a stated salary as director or a fixed sum for attendance at each meeting of the Board of Directors or committee thereof or both. No such payment shall preclude any director from serving the Corporation in any other capacity and receiving compensation therefor.

Section 11. Presumption of Assent. A director of the corporation who is present at a meeting of the Board of Directors at which action on any corporate matter is taken shall be presumed to have assented to the action taken unless his dissent shall be entered in the minutes of the meeting or unless he shall file his written dissent to such action with the person acting as the Secretary of the meeting before the adjournment thereof or shall forward such dissent by registered mail to the Secretary of the corporation immediately after the adjournment of the meeting. Such right to dissent shall not apply to a director who voted in favor of such action.

ARTICLE IV. OFFICERS

Section 1. Election of Officers; Terms. The officers of the Corporation shall consist of a President, a Secretary and a Treasurer. Other officers, including a Chairman of the Board, one or more Vice Presidents (whose seniority and titles, including Executive Vice Presidents and Senior Vice Presidents, may be specified by the Board of Directors), and assistant and subordinate officers, may from time to time be elected by the Board of Directors. All officers shall hold office until the next annual meeting of the Board of Directors and until their successors are elected. The President shall be chosen from among the Directors. Any two officers may be combined in the same person as the Board of Directors may determine, except that the President and Secretary may not be the same person.

Section 2. Removal of Officers; Vacancies. Any officer of the Corporation may be removed by the Board of Directors whenever in its judgment the best

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interests of the Corporation will be served thereby. Vacancies may be filled by the Board of Directors.

Section 3. Duties. The officers of the Corporation shall have such duties as generally pertain to their offices, respectively, as well as such powers and duties as are prescribed by law or are herein provided or as from time to time shall be conferred by the Board of Directors. The Board of Directors may require any officer to give such bond for the faithful performance of his duties as the Board may see fit.

Section 4. Compensation. The Board of Directors shall have authority to fix the compensation of all officers of the Corporation.

ARTICLE V. CONTRACTS, LOANS, CHECKS AND DEPOSITS

Section 1. Contracts. The Board of Directors may authorize any officer or officers, agent or agents, to enter into any contract or execute and deliver any instrument in the name of and on behalf of the corporation, and such authority may be general or confined to specific instances.

Section 2. Loans. No loans shall be contracted on behalf of the corporation and no evidence of indebtedness shall be issued in its name unless authorized by a resolution of the Board of Directors. Such authority may be general or confined to specific instances. The Board of Directors may encumber and mortgage real estate and pledge, encumber and mortgage stocks, bonds and other securities and other personal property of all types, tangible and intangible, and convey any such property in trust to secure the payment of corporate obligations.

Section 3. Checks, Drafts, etc. All checks, drafts, or other orders for the payment of money, notes or other evidence of indebtedness issued in the name of the corporation shall be signed by such officer or officers, agent or agents of the corporation and in such manner as shall from time to time be determined by resolution of the Board of Directors.

Section 4. Deposits. All funds of the corporation not otherwise employed shall be deposited from time to time to the credit of the corporation in such banks, trust companies or other depositaries as the Board of Directors may select.

ARTICLE VI. CERTIFICATES FOR SHARES AND THEIR TRANSFER

Section 1. Certificates for Shares. Certificates representing shares of the corporation shall be in such form as shall be determined by the Board of Directors. Such certificates shall be signed by the President or a Vice President and by the Secretary or an Assistant Secretary and sealed with the corporate seal or a facsimile thereof. The signatures of such officers upon a certificate may be facsimiles if the certificate is manually signed on behalf of the transfer agent or a registrar, other than the corporation itself or one of its employees. Each certificate for shares shall be consecutively numbered or otherwise identified. The name and address of the person to whom the shares represented thereby are issued, with the number of shares and date of issue, shall

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be entered on the stock transfer books of the corporation. All certificates surrendered to the corporation for transfer shall be cancelled and no new certificate shall be issued until the former certificate for a like number of shares shall have been surrendered and cancelled, except that in case of a lost, destroyed or mutilated certificate a new one may be issued therefor upon such terms and indemnity to the corporation as the Board of Directors may prescribe.

Section 2. Transfer of Shares. Transfer of shares of the corporation shall be made only on the stock transfer books of the corporation by the holder of record thereof or by his legal representative, who shall furnish proper evidence of authority to transfer, or by his attorney thereunto authorized by power of attorney duly executed and filed with the Secretary of the corporation, and on surrender for cancellation of the certificate for such shares. The person in whose name shares stand on the books of the corporation shall be deemed by the corporation to be the owner thereof for all purposes.

Section 3. Lost Certificates. Any person claiming a certificate of shares to be lost or destroyed shall make an affidavit or affirmation of that fact, and if requested to do so by the Board of Directors of the corporation shall advertise such fact in such manner as the Board of Directors may require, and shall give the corporation a bond of indemnity in such sum as the Board of Directors may direct, but not less than double the value of shares represented by such certificate, in form satisfactory to the Board of Directors, may prescribe; whereupon the President and the Secretary may cause to be issued a new certificate of the same tenor and for the same number of shares as the one alleged to have been lost or destroyed, but always subject to the approval of the Board of Directors.

Section 4. Stock Transfer Books. The stock transfer books of the corporation shall be kept in the principal office of the corporation and shares shall be transferred under such regulations as may be prescribed by the Board of Directors.

ARTICLE VII. FISCAL YEAR

The fiscal year of the corporation may be fixed and may be changed from time to time by resolution of the Board of Directors. Until the Board of Directors has acted to fix such fiscal year, the fiscal year of the corporation shall begin on the 1st day of November and end on the 31st day of October of each year.

ARTICLE VIII. DIVIDENDS

The Board of Directors may, from time to time, declare, and the corporation may pay, dividends on its outstanding shares in the manner and upon the terms and conditions provided by law and its Articles of Incorporation.

ARTICLE IX. CORPORATE SEAL

The Board of Directors shall provide a corporate seal, which shall be circular in form and shall have inscribed thereon the name of the corporation and the state of incorporation and the word “SEAL”.

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ARTICLE X. WAIVER OF NOTICE

Whenever any notice is required to be given to any shareholder or director of the corporation under the provisions of these by-laws or under the provisions of the Articles of Incorporation or by law, a waiver thereof in writing signed by the person or persons entitled to such notice, whether before or after the time stated therein, shall be deemed equivalent to the giving of such notice.

ARTICLE XI. AMENDMENTS

These by-laws may be altered, amended or restated and new by-laws may be adopted by the Board of Directors at any regular or special meeting.

ARTICLE XII. VOTING SHARES OF OTHER CORPORATIONS

Unless otherwise ordered by the Board of Directors, shares in other corporations held by this corporation may be voted by the Chairman of the Board or the President of this corporation.

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