EXHIBIT 4.6



                       TANKNOLOGY-NDE INTERNATIONAL, INC.

                             STOCK OPTION AGREEMENT
                             FOR 1995 INCENTIVE PLAN
                          FOR NON-MANAGEMENT EMPLOYEES


Tanknology-NDE  International,  Inc., a Delaware  Corporation  (the  "Company"),
hereby grants this *** day of ****, 199**, to ***** (the "Optionee"),  an option
to purchase a maximum of **** shares of its Common  Stock,  $.001 par value,  at
the price $ .*** per share, on the following terms and conditions:

1.   Grant Under 1995 Incentive Plan for Non-Management  Employees.  This Option
is granted  pursuant to and is governed by the Company's 1995 Incentive Plan For
Non-Management  Employees,  as amended  (the  "Plan")  and,  unless the  context
otherwise  requires,  terms used  herein  shall have the same  meaning as in the
Plan. To the extent not specifically  defined herein,  capitalized terms used in
this  Agreement  shall have the same  meanings  ascribed to them in the Plan. By
execution of this Agreement,  the Optionee acknowledges receipt of a copy of the
Plan.  Determinations  made in connection  with this Option pursuant to the Plan
shall be governed by the Plan as it exists on this date.

2.   Grant as Non-Qualified  Option; Other Options. This Option shall be treated
for  federal  income tax  purposes as a  Non-Qualified  Option  (rather  than an
Incentive  Stock  Option),  and the Board of  Directors  will  take  appropriate
action, if necessary,  to achieve this result. This Option is in addition to any
other Options  heretofore or hereafter granted to the Optionee by the Company. A
duplicate  original  of this  instrument  shall not  effect the grant of another
Option.

3.   Extent of Option If Business  Relationship  Continues.  If the Optionee has
continued to serve the Company or any Subsidiary (as defined in the Plan) in the
capacity of an  employee,  officer,  director  or  consultant  (such  service is
described  herein as maintaining or being involved in a "Business  Relationship"
with the Company) on the following  dates, the Optionee may exercise this Option
for the number of shares set opposite the applicable date:

         Less than one year from
         *****, 199*                             -0- shares


         One year but less than
         two years from up to
         *****, 199*                             up to 1/3 of the shares granted


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         Two years but less than                 an additional 1/3 of the shares
         three years from ****, 199*             granted



         Three years but less than
         ten years from ****, 199*               all of  the shares granted



The  foregoing  rights are  cumulative  and,  while the  Optionee  continues  to
maintain a Business  Relationship  with the Company,  may be exercised up to and
including  the date which is 10 years from the date this Option is granted.  All
of the foregoing rights are subject to Articles 4, 12 and 13, as appropriate, if
the  Optionee  ceases to  maintain a Business  Relationship  with the Company or
dies,  becomes  disabled or undergoes  dissolution  while involved in a Business
Relationship with the Company.

4.   Termination of Business Relationship.  If the Optionee ceases to maintain a
Business Relationship with the Company, other than by reason of death as defined
in Article 5, no further  installments  of this Option shall become  exercisable
and this Option shall  terminate  after the passage of ninety (90) days from the
date the Business  Relationship ceases, but in no event later than the scheduled
expiration  date. In such a case, the Optionee's only rights  hereunder shall be
those which are properly exercised before the termination of this Option.

5.   Death;  Dissolution.  If the Optionee  is a natural  person  who dies while
involved  in a  Business  Relationship  with the  Company,  this  Option  may be
exercised,  to the  extent of the  number of shares  with  respect  to which the
Optionee  could  have  exercised  it on the date of his  death,  by his  estate,
personal  representative  or  beneficiary  to whom this Option has been assigned
pursuant to Article 10, at any time within one hundred  eighty  (180) days after
the date of death,  but not later than the  scheduled  expiration  date.  If the
Optionee is a corporation, partnership, trust or other entity that is dissolved,
liquidated,  becomes  insolvent  or  enters  into a merger or  acquisition  with
respect to which such Optionee is not the surviving entity at the time when such
entity is  involved in a Business  Relationship  with the  Company,  this Option
shall  immediately  terminate as of the date of such event,  and the only rights
hereunder shall be those as to which this Option was properly  exercised  before
such dissolution or other event.


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6.   Partial Exercise. Exercise of this Option up to the extent above stated may
be made in part at any time and  from  time to time  within  the  above  limits,
except that this Option may not be  exercised  for a fraction of a share  unless
such exercise is with respect to the final  installment of stock subject to this
Option and a fractional share (or cash in lieu thereof) must be issued to permit
the Optionee to exercise completely such final installment. Any fractional share
with respect to which an installment of this Option cannot be exercised  because
of the  limitation  contained in the preceding  sentence shall remain subject to
this  Option  and shall be  available  for later  purchase  by the  Optionee  in
accordance with the terms hereof.

7.   Payment of Price.  The Option price is payable in United States dollars and
may be paid in cash or by check or any  combination of the  foregoing,  equal in
amount to the Option price; plus all withholding taxes due.

8.   Agreement to Purchase for  Investment.  By acceptance  of this Option,  the
Optionee  agrees  that a purchase  of shares  under this Option will not be made
with a view to their distribution, as that term is used in the Securities Act of
1933,  as  amended,  unless  in the  opinion  of  counsel  to the  Company  such
distribution  is  in  compliance  with  or  exempt  from  the  registration  and
prospectus  requirements  of  that  Act,  and  the  Optionee  agrees  to  sign a
certificate to such effect at the time of exercising this Option and agrees that
the  certificate  for the shares so purchased may be inscribed  with a legend to
ensure compliance with that Act.

9.   Method of Exercising  Option.  Subject to the terms and  conditions of this
Agreement, this Option may be exercised by written notice to the Company (to the
attention of the corporate Secretary located at 8900 Shoal Creek Blvd., Building
200,  Austin,  Texas  78757,  or to such  transfer  agent as the  Company  shall
designate.  Such notice shall state the election to exercise this Option and the
number of shares in respect of which it is being  exercised  and shall be signed
by the  person or  persons so  exercising  this  Option.  Such  notice  shall be
accompanied  by  payment  of the full  purchase  price of such  shares,  and the
Company shall deliver a certificate or certificates  representing such shares as
soon as  practicable  after the notice shall be  received.  The  certificate  or
certificates for the shares as to which this Option shall have been so exercised
shall be  registered  in the name of the person or persons  so  exercising  this
Option  (or,  if this  Option  shall be  exercised  by the  Optionee  and if the
Optionee  shall so  request  in the  notice  exercising  this  Option,  shall be
registered in the name of the Optionee and another person jointly, with right of
survivorship)  and shall be delivered  as provided  above to or upon the written
order of the person or persons  exercising this Option. In the event this Option
shall be exercised, pursuant to Article 5 hereof, by any person or persons other
than the Optionee,  such notice shall be accompanied by appropriate proof of the
right of such person or persons to exercise  this Option.  All shares that shall
be purchased upon the exercise of this Option as provided  herein shall be fully
paid and non-assessable.

10.  Option Not  Transferable.  This Option is not  transferable  or  assignable
except by will or by the laws of descent and distribution. During the Optionee's
lifetime, only the Optionee can exercise this Option.


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11.  No Obligation to Exercise  Option.  The grant and acceptance of this Option
imposes no obligation on the Optionee to exercise it.


12.  No  Obligtion  to  Continue  Business  Relationship.  The  Company  and any
Subsidiary are not by the Plan or this Option  obligated to continue to maintain
a Business Relationship with the Optionee.

13.  No Rights as Stockholder until Exercise.  The Optionee shall have no rights
as a stockholder  with respect to shares subject to this Agreement until a stock
certificate  therefor  has been  issued to the  Optionee  and is fully paid for.
Except as is expressly  provided in the Plan with respect to certain  changes in
the capitalization of the Company,  no adjustment shall be made for dividends or
similar  rights  for  which  the  record  date is prior to the date  such  stock
certificate is issued.

14.  Capital Changes and Business Successions.  It is the purpose of this Option
to encourage the Optionee to work for the best  interests of the Company and its
stockholders.  Since,  for example,  that might  require the issuance of a stock
dividend or a merger with another corporation,  the purpose of this Option would
not be served if such a stock dividend, merger or similar occurrence would cause
the Optionee's rights hereunder to be diluted or terminated and thus be contrary
to the Optionee's  interest.  The Plan contains extensive provisions designed to
reserve  options  at  full  value  in  a  number  of  contingencies.  Therefore,
provisions in the Plan for  adjustment  with respect to stock subject to options
and the related  provisions  with respect to  successors  to the business of the
Company are hereby made  applicable  hereunder  and are  incorporated  herein by
reference. In particular,  without affecting the generality of the foregoing, it
is  understood  that for the  purposes  of  Articles  3 through  5 hereof,  both
inclusive,  maintaining  or being involved in a Business  Relationship  with the
Company includes maintaining or being involved in a Business Relationship with a
Related Corporation as defined in the Plan.

15.  Withholding Taxes. The Optionee hereby agrees that the Company may withhold
from the  Optionee's  wages or other  remuneration  the  appropriate  amount  of
federal,  state and local taxes  attributable to the Optionee's  exercise of any
installment of this Option. At the Company's discretion,  the amount required to
be withheld may be withheld in cash from such wages or other remuneration, or in
kind from the Common Stock otherwise  deliverable to the Optionee on exercise of
this Option.  The Optionee further agrees that, if the Company does not withhold
an amount from the Optionee's wages or other remuneration  sufficient to satisfy
the Company's withholding obligation, the Optionee will reimburse the Company on
demand, in cash, for the amount underwithheld. If Optionee is not an employee of
the  Company,   Optionee  acknowledges  by  signing  this  Agreement  that  upon
Optionee's  exercise of the Option the Company will not collect from Optionee or
pay any  contributions to Social Security,  unemployment  insurance,  federal or
state withholding taxes, nor provide any other  contributions for benefits which
might be expected in an employer-employee relationship.



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16.  Amendment and Termination.  This Agreement may be amended only by a written
agreement  executed by the Company and the  Optionee.  The Company may terminate
the Plan at any time,  provided that such  termination will not modify the terms
and conditions of the Option granted hereunder without the Optionee's consent.

17.  Change In Control. Upon a Change in Control (as such term is defined in the
Plan),  the  Company  may, in its  discretion,  but shall not be  obligated  to,
accelerate the exercise dates of this Option,  pay cash to the Optionee equal to
the spread  between the Purchase Price and the Fair Market Value in exchange for
the cancellation of the Option, or, with the consent of the Optionee, substitute
new options or make any necessary  adjustment  or amendment to this Option.  The
existence of the Option shall not affect the right of the Company to reclassify,
recapitalize  or  otherwise  change its capital or debt  structure  or to merge,
consolidate,  convey any or all of its assets, dissolve,  liquidate,  wind up or
otherwise reorganize.

18.  Governing  Law.  This  Agreement  shall be governed by and  interpreted  in
accordance with the internal laws of the State of Delaware.





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IN WITNESS  WHEREOF the Company and the Optionee have caused this  instrument to
be executed, and the Optionee whose signature appears below acknowledges receipt
of a copy of the Plan and acceptance of an original copy of this Agreement.



---------------------------                   TANKNOLOGY-NDE INTERNATIONAL, INC.
Optionee's Name


---------------------------                   By:_______________________________
Optionee's Signature


---------------------------
Print Name of Employee


---------------------------
Title


---------------------------
Street Address

---------------------------
City, State, zip code

---------------------------
Social Security I.D. Number

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