Exhibit 3.16


                                     BY-LAWS

                                       OF

                         FLY ASH PRODUCTS, INCORPORATED

                                    ARTICLE I

                           Name, purpose and location

      SECTION I: The name of this corporation is FLY ASH PRODUCTS, INCORPORATED.

      SECTION II: The nature of the business of the corporation, its objects,
powers, and purposes to be transacted, promoted, or carried on by it are set
forth in the Articles of Incorporation.

      SECTION III: The corporation's principal office shall be located at 511
Commerce Street, P. O. Drawer 8597, Pine Bluff, Jefferson County, Arkansas,
until changed or additional offices authorized by action of the Board of
Directors.

                                   ARTICLE II

                                  Capital Stock

      SECTION I: The amount of capital stock shall be 1,000 shares of common
stock at a par value of $ .10 per share.

      SECTION II: All certificates of stock shall be signed by the President and
Secretary- Treasurer, and shall be sealed with the corporate seal.

      SECTION III: Transfers of stock shall be made only on the books of the
corporation; and any purported transfer shall not be complete until transferred
on such books and the old


certificates, properly endorsed, shall have been surrendered and canceled before
a new certificate is issued. The stock books of the corporation shall be closed
against transfers for a period of 30 days prior to the date of payment of a
dividend and for 10 days before each annual meeting of the stockholders. Any and
all transfer tax that may be required on any transfer must be paid before
transfer and paper record is made thereof.

      SECTION IV: That 30 days prior to the annual stockholders' meeting, any
stock paid for to that date but unissued upon any subscription contract or
otherwise, shall be forthwith issued and delivered to the subscribing
stockholder, who shall be entitled to participate in the annual stockholders'
meeting and to receive a pro rata share of the dividends as if the stock had
been issued for the entire year preceding.

      SECTION V: In case of loss or destruction of a certificate of stock, no
new certificate shall be issued in lieu thereof except upon satisfactory proof
to the Board of Directors of such loss or destruction, and upon the giving of
satisfactory security, by bond or otherwise, against loss to the corporation.
Any such certificate shall be marked "Duplicate" on its face.

      SECTION VI: No stock shall be issued on original issue to any person not a
bona fide resident of the State of Arkansas and then only after satisfactory
investigation of his residency shall have been made.

      SECTION VII: Certificates of stock shall be issued in numerical order from
the stock book on a form not inconsistent with the Articles of Incorporation and
shall be prepared and approved by the Board of Directors. A record of each
certificate shall be kept on the stock certificate book.


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      SECTION VIII: Dividends to be paid on stock shall be paid pro rata for
each share and in such amounts as may be declared by the Board of Directors,
either in cash, or by stock dividend. No dividend shall be made which would
impair the capital of the corporation.

      SECTION IX: Each share of stock shall entitle its holder, as shown on the
corporate records, to vote one vote, either in person or by proxy at any
stockholders' meeting. Unissued stock shall be non-voting. Treasurer's stock
shall be non-voting.

      SECTION X: No stock shall be issued without payment in cash, or property,
or services. 

                                  ARTICLE III

                            Officers and their Duties

      SECTION I: The officers of this corporation shall be a President, a
Vice-President, a Secretary and a Treasurer, who shall be elected by the Board
of Directors for a term of one year. The office of the Secretary and Treasurer
may be occupied by the same individual. Upon proper authorization of the Board
of Directors, the Board of Directors may elect a Chairman of the Board of
Directors.

      SECTION II: The offices to be filled shall be by majority vote of the
Board of Directors at the annual Board of Directors' meeting. Vacancies may be
filled by the Board of Directors for the balance of the year prior to the next
annual Board of Directors' meeting when such vacancy occurs or the office is
declared to be vacant for the first time.

      SECTION III: The President shall preside at all Directors' meetings,
provided a Chairman of the Board shall not have been elected, and at all
Stockholders' meetings; sign all stock certificates; have general supervisory
duties over the affairs of the corporation and over the


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other officers and directors; and shall perform the general overall duties
commensurate with his office and as required in the regular course of business
of the corporation, including the purchase, acquisition or disposition of the
properties of the corporation. He shall co-sign checks, unless otherwise
designated by the Board of Directors.

      SECTION IV: The Vice-President shall assume all duties of the President in
his absence or incapacity, and shall perform such duties as may be assigned by
the President.

      SECTION V: The Secretary shall give all notices required by the By-laws,
Board of Directors, and the President. He shall keep accurate and complete
minutes of all meetings subject to the examination of any stockholder, officer,
or director at any time after reasonable notice of such demand for examination.
The Secretary shall sign all stock certificates and keep accurate record of all
stock transactions, and perform all required duties commensurate with the
issuance of stock and the ordinary duties of a corporate secretary.

      SECTION VI: The Treasurer shall keep an accurate record of the finances of
the corporation, maintain a bank account and the records of financial standing
of the corporation and make a report thereof to the Board of Directors at each
regular meeting thereof; and shall furnish an annual report thereof to the
stockholders at the annual meeting; and furnish such other reports as required
by the President. The annual report to the stockholders shall be audited by a
certified public accountant prior to its submission, unless the Board of
Directors otherwise directs. The Treasurer shall sign all checks of the
corporation, unless the Board of Directors otherwise directs.

      SECTION VII: Upon proper motion and direction of the Board of Directors,
an Assistant Treasurer and an Assistant Secretary may be authorized and their
duties shall be the same as the Treasurer and Secretary respectively.


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      SECTION VIII: Provided a Chairman of the Board of Directors be established
by the Board of Directors, his duties shall consist of the general supervision
of the Board of Directors, the preparation of and submission of such business as
should properly come before the Board of Directors and he shall preside over
each meeting of the Board of Directors.

      SECTION IX: The officers of the corporation shall receive such
compensation for their services as may be set by unanimous vote of the Board of
Directors. All officers shall be stockholders.

                                   ARTICLE IV

                        Directors and Directors' Meetings

      SECTION I: The business and property of the corporation shall be generally
managed by the Board of Directors of a minimum of 3 and a maximum of 7 members,
who shall be elected by the stockholders for the term of one year at the annual
stockholders' meeting. Each director must be a stockholder of the corporation.
The President shall be governed in his activity of management of the corporate
affairs by the Board of Directors.

      SECTION II: The Board of Directors shall hold an annual meeting
immediately subsequent to the annual meeting of the stockholders at which time
the newly elected members thereof shall take office for the ensuing year. No
notice of this meeting shall be required in advance of the annual stockholders'
meeting.

      SECTION III: The Board of Directors shall hold such other meetings as
called by the Board of Directors, the President or, in the President's absence,
by the Secretary, and the Chairman of the Board, if elected. Notice of the place
and time and purpose of any call meeting of the Board shall be mailed to the
also known address of each member of the Board of Directors


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at least 2 days in advance of such meeting date by the Secretary. Notice of any
meeting of the Board of Directors may be waived prior to, at, or after the
meeting.

      SECTION IV: Two-thirds of the number of elected members of the Board of
Directors shall constitute a quorum for any meeting and a majority of those
present shall constitute an active Board.

      SECTION V: The Board of Directors shall at each annual Board of Directors'
meeting pass upon the advisability of declaring dividends, either cash or stock.

                                    ARTICLE V

                     Stockholders and Stockholders' Meetings

      SECTION I: Each Stockholder of this corporation, upon any original issue
of stock, shall be a bona fide resident of the State of Arkansas, as of the time
of its issue.

      SECTION II: Any holder of stock, as shown upon the stock book of the
corporation, shall be entitled to one vote for each share of stock at any
meeting of the stockholders. Each shall be entitled to all other rights and
privileges afforded by ownership of stock in the Corporation.

      SECTION III: An annual meeting of the stockholders shall be held on the
date set by the Board of Directors during the fourth week of January of each
year. Notice of the time and place of said meeting shall be mailed to the last
known address, as shown upon the records of the corporation, of each stockholder
by the Secretary at least 10 days prior to such meeting. Notice may be waived in
writing before, at, or after such meeting in the presence, either in person or
by proxy, shall constitute waiver of such notice.


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      SECTION IV: Special meetings of the stockholders may be called by the
Board of Directors at designated times and places as may be set. Notice of such
special meetings of the stockholders shall be mailed to the last known address,
as shown on the records of the corporation, at least 10 days in advance of such
meeting. The notice shall include the purposes of said meeting. Notice may be
waived in writing before, at, or after such meeting in presence in person or by
proxy and shall constitute waiver of notice.

      SECTION V: The stockholders shall elect a minimum of 3 and a maximum of 7
directors at each annual meeting by majority vote. Each stockholder shall be
entitled to vote for each director.

      SECTION VI: A majority vote of outstanding stock may amend the Articles of
Incorporation.

                                   ARTICLE VI

                                   Amendments

      SECTION I: These By-laws may be amended by 3/5 vote of the filled
positions of the Board of Directors. Notice of the amendments so made shall be
announced at each subsequent annual meeting of the stockholders.

      Adopted this _____ day ____________, 19__.


                                          --------------------------------------
                                          Secretary


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