EXHIBIT 10.20
                                  INTEREST ONLY
                           NONRECOURSE PROMISSORY NOTE
                             AND SECURITY AGREEMENT

$400,000.00                                                      2/23/03  [Date]
                                                                 -------
                                                           Portsmouth,  Virginia

     FOR VALUE RECEIVED, H.E.R.C. Products Incorporated, a Delaware corporation,
("Maker" or "Debtor") promises to pay to R. John Armstrong ("Holder" or "Secured
Party"),  or  order,  the  principal  sum  of  Four  Hundred  Thousand  Dollars
($400,000.00) with interest from the date of this Note on unpaid principal owing
from  time  to  time  at  the rate of eight percent (8.0%) per annum until fully
paid.   Maker  shall  make interest only payments on the first day of each month
from  the  date  of  this Note until the date one (1) year from the date of this
Note  ("Maturity  Date"). Principal plus all accrued and unpaid interest on such
principal  shall  be  due  and  payable  on  the  Maturity  Date.

     Maker  shall  make  all  payments  in  lawful money of the United States of
America  and  in  immediately available funds. Computations of interest shall be
based  on  a  year  of 360 days but shall be calculated for the actual number of
days  in  the  period  for  which  interest  is  charged.

     This  Note  may  be  prepaid  in  whole or in part, without penalty, at the
option of Maker and without the consent of Holder. All payments shall be applied
first  to  accrued  and  unpaid  interest  and  then  to  the  principal balance
outstanding.  All  payments  under  this Note shall be paid to Holder at Seaward
Marine  Services,  Inc.,  Attention:  R.  John Armstrong, 3975 University Drive,
Suite  400,  Fairfax,  Virginia  22030 marked "PERSONAL and CONFIDENTIAL", or at
such  other  address  as  Holder  shall  direct  Maker  in  writing.

     This  Note  is  nonrecourse as to Maker, except as to those assets of Maker
described  in  the  Security  Agreement  between  Maker  as Debtor and Holder as
Secured Party ("Security Agreement") and a UCC-1 Financing Statement, both dated
the  same  date  as this Note ("Collateral"). In the event Holder is entitled to
proceed  against  Maker,  Holder's sole recourse shall be to proceed against the
Collateral  pursuant  to  the  terms set forth in the Security Agreement. Holder
shall have no other recourse against Maker or any assets of Maker other than the
Collateral.  This provision is not intended to constitute a discharge or release
of  any  obligation  contained  in  this  Note  or  security  that  secures such
obligations,  but  is  a  covenant  by Holder not to sue Maker for a deficiency.

     In  the  event  of  any failure to pay when due any installment of interest
under this note, and the continuance of that failure to pay for a period of (10)
days  after written notice, by certified or registered mail or by hand delivery,
of  this  failure, this promissory note shall be considered to be in default and
the  entire  unpaid  principal sum, together with accrued interest, shall at the
option  of  the  holder  become  immediately  due  and  payable  in  full.

     The  laws  of  the  State  of Virginia excluding its conflict of laws rules
shall govern this Note. The exclusive jurisdiction and venue of any legal action
instituted  by  any  party  to  this  Note  shall  be  Fairfax,  Virginia.

     Maker  waives presentment, protest and demand, notice of protest, notice of
demand  and  dishonor,  and  notice  of nonpayment of this Note. Maker expressly
agrees that Holder may extend this Note or any payment under this Note from time
to  time  without  in  any  way  affecting  the  liability  of  Maker.

      Maker  shall pay all costs and expenses, including attorney fees, incurred
(i) in collecting payment on this Note, (ii) in connection with any dispute that
arises  as to its enforcement, validity, or interpretation, whether or not legal
action  is  instituted  or  prosecuted  to  judgment,  or (iii) in enforcing any
judgment  obtained  in  any  related  legal  proceeding.

     If  any  provision  or  any word, term, clause, or part of any provision of
this  Note  shall  be invalid for any reason, the same shall be ineffective, but
the  remainder of this Note and of the provision shall not be affected and shall
remain  in  full  force  and  effect.


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     Any  of  the terms and conditions of this Note may be waived by Holder, but
no  such  waiver  shall  affect  or  impair  the  rights  of  Holder  to require
observance, performance, or satisfaction, either of that term or condition as it
applies on a subsequent occasion or of any other term or condition of this Note.

     This  Note  shall be secured by Collateral in the Security Agreement made a
part  hereof  as  follows:


                                   SECTION ONE

                          CREATION OF SECURITY INTEREST

Debtor grants, and secured party retains a security interest in all of company's
present  and future inventory, accounts, account and contract rights, contracts,
drafts,  acceptances,  documents,  instruments, chattel paper, deposit accounts,
general intangibles and all products and proceeds therefrom, all of which are in
this  instrument  referred  to as "collateral," subject to prior encumbrance and
security  interest  under  that  certain agreement by and between debtor and KBK
Financial,  Inc.  dated September 22, 1997, as amended, to secure payment of the
following:

    A.  The  debt  evidenced  by  this  instrument.

    B. All costs and expenses incurred by secured party in the collection of the
debt.

    C.  All  future  advances made by secured party for taxes, levies, insurance
and  repairs  to  or  maintenance  of  collateral.

    D.  All  other  future advances that may, at the option of secured party, be
made  or  given  by  secured  party  to  or  for  the  account  of  debtor.

    E.  All  other  past,  present,  future, direct or contingent liabilities of
debtor  to  secured  party.


                                   SECTION TWO

                                 PURPOSE OF LOAN

Secured  party  has  loaned  the above sum to debtor to enable debtor to provide
operational  working  capital  and  other  general  corporate  purposes.


                                  SECTION THREE

                         PERFECTION OF SECURITY INTEREST

Debtor  shall  pay all filing fees with respect to the security interest created
by  this  agreement,  and  secured  party  is  by  this  agreement appointed the
attorney-in-fact  of  debtor  to  perform  all  acts that secured party may deem
necessary  to  perfect  and  continue  perfecting  such  security  interest.


<PAGE>

                                  SECTION FOUR

                         LOCATION OF BUSINESS OF DEBTOR

The place of business of debtor for the purpose of sale of collateral is at 1420
Columbus  Avenue,  Portsmouth,  Virginia  23704.  Debtor  has  no other place of
business  in Virginia. Debtor shall promptly notify secured party in writing of:

    A.  Any  change  in  location  of  any  place  of  business.

    B.  Establishment  of  any  new  place  of  business.

    C.  Discontinuance  of  any  established  place  of  business.


                                  SECTION FIVE

                            PROTECTION OF COLLATERAL

Debtor  shall maintain collateral in good condition and repair and shall pay and
discharge  all taxes, levies and other impositions levied on collateral, as well
as  the  cost  of repairs to or maintenance of collateral. If debtor fails to do
so,  secured  party  may  pay  the  cost of such maintenance or repairs and such
taxes,  levies  and  impositions for the account of debtor, adding the amount of
the  same  to  the  debt  secured by this agreement. Debtor shall permit secured
party  to  inspect  collateral and the books and records of debtor pertaining to
the  collateral at any reasonable time. Debtor shall not lease, mortgage, pledge
or  encumber  collateral, permit its identity to be lost, permit it to be levied
on  or  attached under any legal process, or create any security interest in the
collateral  other  than the security interest created by this agreement, subject
to  prior  encumbrance  and  security interest referenced in Section One hereof.


                                   SECTION SIX

                                  RISK OF LOSS

Risk  of  loss,  damage  to  or  destruction  of  collateral  is  on  debtor.



                                  SECTION SEVEN

                        RIGHTS AND REMEDIES UNDER STATUTE

In  addition  to  all  rights given to secured party by this promissory note and
security  agreement,  secured  party shall have all the rights and remedies of a
secured party under VA ST T. 8.9A and otherwise accorded by the law in Virginia.


<PAGE>

                                  SECTION EIGHT

                             CONFESSION OF JUDGMENT

Debtor  empowers any attorney of any court of record within the United States to
appear  for  debtor  and, with or without one or more complaints or declarations
filed,  confess a judgment or judgments against debtor in favor of the holder of
this  note  and  agreement,  as  of  any  term,  for  the above sum plus accrued
interest,  together  with costs of suit and attorney fees of 1.0%. Debtor waives
all  errors  and stays of execution. The exemption of all property from levy and
sale  on  any  execution  is  also  waived, and no benefit of exemption shall be
claimed  under  or by virtue of any exemption law now in force or that may later
be  enacted.


                                  SECTION NINE

                                  SEVERABILITY

If  any  provision  of  this  instrument shall for any reason be held invalid or
unenforceable,  such  invalidity  or unenforceability shall not affect any other
provision  of  this  instrument, but this promissory note and security agreement
shall  be construed as if such invalid or unenforceable provision had never been
contained  in  this  instrument.


                                   SECTION TEN

                              EFFECT OF INSTRUMENT

The  rights and privileges of secured party under this instrument shall inure to
the  benefit  of the successors and assigns of secured party, and the duties and
obligations  of  debtor  under  this  instrument  shall bind the heirs, personal
representatives,  successors  and  assigns  of debtor. If there is more than one
debtor,  the  warranties,  covenants  and agreements of debtor contained in this
instrument,  including  the foregoing confession of judgment, shall be joint and
several.

Executed  at  Portsmouth,  Virginia  the  day  and  year  first  above  written.


MAKER/DEBTOR

H.E.R.C.  Products  Incorporated,
a  Delaware  corporation

By:    S.  Steven  Carl,  CEO
     ------------------------


[Signature]

  /s/   S.  Steven  Carl
------------------------


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