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                                                                    Exhibit 4(x)
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                   THREE-YEAR 9 3/4% SECURED PROMISSORY NOTE


THIS PROMISSORY NOTE HAS BEEN ISSUED WITHOUT REGISTRATION UNDER THE SECURITIES
ACT OF 1933 ("ACT"), OR THE SECURITIES LAWS OF ANY STATE, PURSUANT TO APPLICABLE
EXEMPTIONS FROM SUCH REGISTRATION.  SUCH NOTE HAS BEEN ACQUIRED FOR INVESTMENT
AND MAY NOT BE SOLD, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED AT ANY TIME
EXCEPT IN ACCORDANCE WITH THE RESTRICTIONS CONTAINED HEREIN AND IN THE
SUBSCRIPTION AGREEMENT USED IN CONNECTION WITH THE ISSUANCE OF THIS NOTE, AND
PURSUANT TO EITHER AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT AND ANY
APPLICABLE STATE SECURITIES LAWS, OR THE RECEIPT BY THE ISSUER HEREOF OF AN
OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO IT THAT SUCH TRANSFER
DOES NOT REQUIRE REGISTRATION UNDER ANY APPLICABLE LAWS.


$[_______] San Antonio, Texas                              Date: _________, 2001


ENVIRO-CLEAN OF AMERICA, INC. ("Maker"), whose address is stated below, for
value received, without grace, in the manner, on the dates and in the amounts
herein stipulated, promises to pay to the order of [___________] ("Payee" or
"Holder") at Payee's address, or such other place as the Payee of this Note may
hereafter designate in writing, the sum of [_______] DOLLARS ($[_______]), in
lawful money of the United States of America, at the interest rate herein
specified.

1.   Definitions.

     (a)  Agent shall mean the Agent for the holder of this Note under the
          Security Agreement, and any successor thereto.

     (b)  Due Date shall mean, as to the payment of interest on this Note, the
          last day of each calendar month following the date hereof, and, as for
          the principal and any unpaid interest, the Maturity Date.

     (c)  Maturity Date shall mean the last business day of the month 36 months
          from the date hereof.

     (d)  Note shall mean this promissory note and any deferrals, renewals,
          extensions, replacements, refinancings and refundings of, or
          amendments, modifications or supplements hereof.

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     (e)  Person shall mean any corporation, individual, partnership (limited or
          general), limited liability company, governmental body or other
          entity.

     (f)  Security Agreement shall mean the Security Agreement, dated October
          31, 2001, executed by Maker in favor of an Agent and Attorney-in-Fact
          for Payee and other holders of other notes of Maker similar to this
          Note, on the personal property described therein, together with all
          proceeds and products thereof.

     (g)  Security Instrument shall mean any security agreement or other
          security instruments or documents relating hereto or executed in
          connection herewith.

2.   Interest Rate.  The unpaid principal balance outstanding hereunder shall
bear simple interest from and after the date hereof until maturity at 9 3/4% per
annum.

3.   Principal and Interest Payments.  This Note shall be due and payable as
follows:

     (a)  Accrued but unpaid interest on the outstanding principal balance of
          this Note shall be due on the last day of each calendar month
          following the date hereof and on the Maturity Date (as defined above)
          and payable within ten days after the amount becomes due.

     (b)  The unpaid principal balance of this Note plus accrued but unpaid
          interest thereon shall be due on the Maturity Date and payable in full
          within ten days after the Maturity Date.

4.   Time, Place and Method of Payment.  All payments made under this Note shall
be made to the holder hereof no later than 5:00 p.m., San Antonio, Texas time,
ten (10) days after the Due Date. Any payment received by the holder after such
time, shall be considered for all purposes (including the calculation of
interest) as having been made on the next succeeding day that the holder is open
for business. If any payment of principal or interest shall become payable on a
legal holiday, such payment shall be payable on the next succeeding business day
and such extension of time shall be included in computing interest due with
respect to such payment. A check, draft, money order, or other instrument given
in payment for any payment or prepayment made hereunder may be accepted by the
holder hereof and handled for collection in the customary manner, but the same
shall not constitute payment hereunder or diminish any rights of the holder
except to the extent that actual cash proceeds of such instrument are
unconditionally and irrevocably received by the holder.

5.   Past Due Rate.  All past due principal and interest on this Note shall bear
interest from the maturity date thereof until the date of payment at 15% per
annum. Interest on this Note shall be computed on the basis of a 365-day year
for the actual number of days elapsed.

6.   Prepayment at the Maker's Option.  Maker may prepay the principal of this
Note, in full or in part, at any time following the date that is two (2) years
from the Issue Date without any prepayment premium or fee and anytime after the
Issue Date, but prior to the date that is two (2) years from the Issue Date,
with a prepayment premium of 1% of the principal amount of the

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Note. Interest accrued but unpaid with respect to any amount prepaid shall be
due and payable on the date of any such prepayment.

7.   Demand of Prepayment by Payee.

     (a)  Payee may demand prepayment of the principal and the  accrued and
          unpaid interest of this Note, in full or in part, at any time
          following the Issue Date with a written notice to the Company of the
          Payee's demand for prepayment; provided, however, that, upon the
          demand for prepayment, the payment of interest may be made by the
          Maker pursuant to the Section 4 of this Note.

     (b)  The Payee's demand of prepayment right may be exercised by the Holder
          by the surrender at the principal office of the Maker of this Note (or
          of any replacement Note issued hereunder) with a written notice to
          demand prepayment. Prepayment shall be deemed to have been effected on
          the date when such delivery of the demand of prepayment notice is
          actually made or, if earlier, at the expiration of three (3) calendar
          days after being sent to the Company by the Holder by registered or
          certified mail, return receipt requested, with postage thereon fully
          prepaid. Within thirty days of receipt of the notice of demand for
          prepayment, the Maker shall issue and deliver to or upon the written
          order of the Holder, a check or wire transfer for the total amount due
          as may be determined in accordance with the above provisions to which
          the Holder is entitled.

8.   Events of Default.   It is expressly agreed and understood that time is of
the essence concerning this Note, and that;

     (a)  if default shall be made in any payment of principal or interest on
          this Note as the same shall become due and payable and such default is
          not cured within 30 days thereafter;

     (b)  if there is a default in any of the terms, covenants, agreements,
          conditions or provisions set forth in any agreement, instrument or
          document given to secure this Note or executed in connection with this
          Note, including but not limited to the Security Agreement, and such
          default is not cured within 30 days after notice thereof by the holder
          hereof to Maker;

     (c)  should Maker, endorser, surety, guarantor or other Person hereafter
          primarily liable upon or for the payment of all or any part of this
          Note (each such Person being hereinafter referred to as an "Other
          Liable Party"), become insolvent or commit an act of bankruptcy or
          make an assignment for the benefit of creditors or authorize the
          filing of a voluntary petition in bankruptcy or should a receiver of
          any of the property of Maker or any Other Liable Party be appointed;

     (d)  should involuntary bankruptcy be filed against either Maker or any
          Other Liable Party;

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     (e)  if a writ or order of attachment or garnishment shall be issued or
          made against any property of the Maker or any Other Liable Party; or

     (f)  if Maker or any Other Liable Party shall be dissolved, wound up,
          liquidated or otherwise;

then in any such event (each an "Event of Default"), subject to this Section 8,
the holder hereof may, at its option, declare the entirety of the outstanding
principal of this Note, together with all accrued but unpaid interest hereon,
immediately due and payable, without notice, protest, demand, presentment,
notice of intent to accelerate or notice of acceleration, all of which are
hereby expressly and specifically waived by Maker and any Other Liable Parties.

9.   Change Of Control.

     (a)  In the event that a Change of Control (as hereinafter defined) (the
date of such occurrence being the "Change of Control Date") occurs, the Company
must, within ten (10) Business Days following the Change of Control Date, send a
notice to the Holder that a Change of Control has occurred and the Holder may
then exercise his rights to demand prepayment as described in Section 7 of this
Note.

     (b)  As used in this "Change of Control" section, "Change of Control"
means:

          (i)       any Person (including any syndicate or group deemed to be a
                    "Person" under Section 13(d)(30 of the Exchange Act), other
                    than the Company, any Subsidiary of the Company or any
                    current or future employee or director benefit plan of the
                    Company or any Subsidiary of the Company or any entity
                    holding capital stock of the Company for or pursuant to the
                    terms of such plan, or an underwriter engaged in a firm
                    commitment underwriting in connection with a public offering
                    of capital stock of the Company, is or becomes the
                    beneficial owner, directly or indirectly, through a
                    purchase, merger or other acquisition transaction or series
                    of transactions of shares of Common Stock of the Company
                    entitling such Person to exercise 50% or more of the total
                    voting power of all shares of Common Stock of the Company
                    entitled to vote generally in the election of directors;

          (ii)      the Company sells or transfers all or substantially all of
                    the assets of the Company to another Person;

          (iii)     there occurs any consolidation of the Company with, or
                    merger of the Company into, any other Person, any merger of
                    another Person into the Company (other than a merger (a)
                    which does not result in any reclassification, conversion,
                    exchange or cancellation of outstanding shares of Common
                    Stock, (b) which is effected solely to change the
                    jurisdiction of incorporation of the Company and results in
                    a reclassification, conversion or exchange of outstanding
                    shares of Common Stock solely into shares of Common Stock,
                    or (c) a transaction in which

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                    the shareholders of the Company immediately prior to such
                    transaction owned, directly or indirectly, immediately
                    following such transaction, at least a majority of the
                    combined voting power of the outstanding voting stock of the
                    Company resulting from the transaction, such stock to be
                    owned by such shareholders in substantially the same
                    proportion as their ownership of the voting stock of the
                    Company immediately prior to such transaction);

          (iv)      a change in the Board of Directors of the Company in which
                    the individuals who constituted the Board of Directors of
                    the Company at the beginning of the 24-month period
                    immediately preceding such change (together with any other
                    director whose election by the Board of Directors of the
                    Company or whose nomination for election by the shareholders
                    of the Company was approved by a vote of at least a majority
                    of the directors then in office either who were directors at
                    the beginning of such period or whose election or nomination
                    for election was previously so approved) cease for any
                    reason to constitute a majority of the directors then in
                    office; or

          (v)       the Common Stock of the Company is the subject of a "Rule
                    13e-3 transaction" as defined under the Exchange Act of
                    1934, as amended.

10.  Severability.  The invalidity, or unenforceability in particular
circumstances, of any provision of this Note shall not extend beyond such
provision or such circumstances and no other provision of this Note shall be
affected thereby.

11.  Usury Prevention.  It is the intention of Maker and Payee to conform
strictly to applicable usury laws.  Accordingly, notwithstanding any provision
to the contrary in this Note, or in any Security Instrument, the aggregate of
all interest and any other charges or consideration constituting interest under
applicable usury law that is taken, reserved, contracted for, charged or
received under this Note, or under any of the Security Instruments, or otherwise
in connection with this loan transaction shall under no circumstances exceed the
maximum amount of interest allowed by the usury law applicable to this loan
transaction.  If any excess interest charge or consideration in such respect is
taken, reserved, contracted for, charged, received or provided for, or shall be
adjudicated to be so taken, reserved, contracted for, charged, received or
provided for, in this Note or in any of the Security Instruments, whether by the
terms of this Note or the Security Instruments  or because the maturity of the
indebtedness evidenced by this Note is accelerated for any reason, or in the
event of any required or permitted prepayment, then in any such event (a) the
provisions of this paragraph shall govern and control, (b) neither Maker nor
Maker's heirs, executors, administrators, legal representatives, successors or
assigns or any Other Liable Party shall be obligated to pay the amount of such
interest to the extent that it is in excess of the legal limit for interest
rates, (c) any excess shall be deemed a mistake and cancelled automatically and,
if theretofore paid, shall be credited on this Note by the holder hereof (or if
this Note shall have been paid in full, refunded to Maker) and (d) the effective
rate of interest shall be automatically subject to reduction to the maximum
interest rate allowed by law as the law may now or hereafter be construed by
courts of appropriate jurisdiction.  Without limiting

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the foregoing, all calculations of the rate of interest taken, reserved,
contracted for, charged, received or provided for under this Note or the
Security Instruments which are made for the purpose of determining whether the
interest rate exceeds the legal limit for interest rates, shall be made, to the
extent allowed by law, by amortizing, prorating, allocating and spreading in
equal parts during the period of the full stated term of the loan evidenced
hereby, all interest at any time taken, reserved, contracted for, charged,
received or provided for under this Note or the Security Instruments.

12.  Security Agreement. The payment of this Note is secured by the Security
Agreement.



                              MAKER:

                              ENVIRO-CLEAN OF AMERICA, INC.
                              1023 Morales Street
                              San Antonio, Texas 78207



                              By:
                                  -----------------------------------------
                                  Randall K. Davis, Chief Executive Officer

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