Exhibit 10.87

                               FIRST AMENDMENT TO
                        FINANCING AND SECURITY AGREEMENT

         THIS FIRST AMENDMENT TO FINANCING AND SECURITY AGREEMENT (this
"Agreement") made as of the 30th day of April, 1997 by and among VERSAR, INC., a
corporation  organized  under the laws of the State of Delaware  ("Versar")  and
GEOMET TECHNOLOGIES,  INC., a corporation  organized under the laws of the State
of  Delaware  (collectively,   the  "Borrowers"  and  each  a  "Borrower"),  and
NATIONSBANK,  N.A., a national banking  association,  its successors and assigns
(the "Lender").

                                    RECITALS

     A. The Borrowers are parties to a certain Financing and Security Agreement,
along with the Lender dated March 31, 1997 (as thereafter amended,  modified and
renewed from time to time,  the  "Financing  Agreement"),  pursuant to which the
Lender has agreed to make  available to the  Borrowers a guidance line of credit
in the maximum principal amount of Five Million Dollars  ($5,000,000) to be used
by the  Borrowers  to finance  Permitted  Acquisitions  and a  revolving  credit
facility in the maximum  principal amount of Three Million Dollars  ($3,000,000)
to be used by the Borrowers to finance  Receivables  all as more fully described
in the Financing  Agreement.  Unless otherwise  defined herein,  all capitalized
terms used herein shall have the meanings  given to such terms in the  Financing
Agreement.

     B. The Borrowers have requested that the Lender make an Acquisition Loan in
the amount of Two Million Dollars  ($2,000,000) for the purpose of acquiring not
less than seventy percent (70%) of the issued and  outstanding  stock of Science
Management Corporation,  a Delaware corporation (together with its subsidiaries,
"SMC") and to amend the  Financing  Agreement in  accordance  with the terms and
conditions set forth below.

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     NOW, THEREFORE,  in consideration of the foregoing,  and for other good and
valuable  consideration,   the  receipt  and  sufficiency  of  which  is  hereby
acknowledged,  the  Borrowers  and the  Lender do hereby  agree as  follows:

     1.  Recitals.  The  parties  hereto  acknowledge  and agree  that the above
Recitals  are true and correct in all  material  respects  and that the same are
incorporated herein and made a part hereof by reference.

     2.  Borrowing  Base.  Subject to the terms and  conditions set forth herein
from the date hereof  through the earlier of: (i) October 31, 1997,  or (ii) the
date on which Versar closes on the sale of its  operations  located in the State
of Utah (such date being called,  the "Borrowing  Base  Conversion  Date"),  the
parties  hereto  agree  that the  definition  of  "Borrowing  Base" set forth in
Section 1.01 of the Financing  Agreement shall be as follows:

          "Borrowing Base" means the sum of (a) ninety percent (90%) of Eligible
     Government  Receivables,  plus (b) eighty  five  percent  (85%) of Eligible
     Subcontractor   Receivables,   plus  (c)  eighty   percent  (80%)  Eligible
     Commercial  Receivables,  plus (d) the lesser of (i) fifty percent (50%) of
     Eligible Unbilled Borrowing Base Receivables, or (ii) $1,500,000, minus the
     sum of (y) the then outstanding  balance of the Acquisitions Notes, and (z)
     the then outstanding balance of the Sarnia Note.

From and after the Borrowing Base Conversion Date, the parties hereto agree that
without  further  notice to the Borrowers,  the  definition of "Borrowing  Base"
shall automatically be as follows:

          "Borrowing Base" means the sum of (a) ninety percent (90%) of Eligible
     Government  Receivables,  plus (b) eighty  five  percent  (85%) of Eligible
     Subcontractor   Receivables,   plus  (c)  eighty   percent  (80%)  Eligible
     Commercial Receivables, less the sum of (y) the then outstanding balance of
     the Acquisitions  Notes, and (z) the then outstanding balance of the Sarnia
     Note.

From and  after  the date  hereof,  for  purposes  of the  Financing  Agreement,
"Eligible Unbilled Borrowing Base Receivables@ means all Accounts arising out of
work actually performed by either

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Borrowers  which (i) are eligible to be billed in accordance with the applicable
contract within thirty (30) days of the Aas of@ date of the applicable Borrowing
Base Certificate (with no additional  performance required by any Person, and no
condition to payment by the account debtor, other than receipt of an appropriate
invoice). The Borrowers understand and agree that any sums outstanding under the
Revolving  Loan in excess of the Borrowing Base shall be due and payable in full
on demand.

     3.  Period to  Complete  Acquisition.  None of the  Accounts  of SMC may be
included by the Borrowers in the  calculation  of the Borrowing  Base until such
date as the  Borrowers  satisfy  the  requirements  of  Sections 4 and 5 of this
Agreement  and  all of the  following  conditions  have  been  satisfied  in the
Lender's  sole and  absolute  discretion  (such date being  called the  "Joinder
Date"):

          (a) The Lender shall have received from the Borrower evidence that all
     of the unsecured  bankruptcy creditors of SMC have either been paid in full
     and fully released their liens on any and all of the assets of SMC, or have
     entered into one or more  subordination  agreements  in form and  substance
     satisfactory in all respects to the Lender and its counsel.

          (b) The Borrowers  shall have provided the Lender with fully  executed
     Subordination Agreements by and among Versar, SMC, and any and all existing
     secured   administrative   claim  lienholders  of  SMC  (the  "Subordinated
     Creditors")  and the  Lender  in form  and  substance  satisfactory  in all
     respects  to  the  Lender  and  its  counsel  (the  "Administrative   Claim
     Subordination").

From and after the Joinder Date,  all Accounts of SMC which in the Lender's sole
and  absolute  discretion  meet  the  Eligibility  Standards  and are  otherwise
acceptable to the Lender in its sole and absolute discretion, may be included by
the Borrowers in the Borrowing Base.

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     4. Joinder of SMC. As soon as possible, but in no event later than June 30,
1997,  the  Borrowers  and SMC shall  execute  and  deliver to the  Lender  such
promissory  notes,  financing  statements,  security  agreements  and such other
documents as the Lender and its counsel may require to (i) add SMC as a co-maker
of the Obligations,  (ii) add SMC as a party to the Financing Agreement and such
other  Financing  Documents  as the Lender may  require,  and (iii) cause SMC to
grant to the  Lender a valid and  perfected  first  lien  security  interest  on
substantially all of the assets of SMC to secure the Obligations.

     5. Audit Period.  As soon as possible,  but in no event later than June 30,
1997, the Borrowers will permit,  and cause SMC to permit, any Person designated
by the Lender to enter the premises of the  Borrower and SMC and examine,  audit
and inspect the books and records of SMC at the Borrowers' expense.  The results
of such audit must be satisfactory to the Lender in all material respects.

     6. Fee. In addition to the Acquisition Loan fee described in this Agreement
and in the Financing  Agreement,  in consideration of the Lender's  agreement to
amend the Revolving  Loan,  the  Borrowers  agree to pay the Lender a fee in the
amount of One Thousand  Dollars  ($1,000) in each month where  advances are made
against Eligible Unbilled Borrowing Base Receivables.  This fee shall be paid in
arrears on the first day of each calendar month.

     7. Representations. The Borrowers hereby represent to the Lender, that upon
the funding of the  Acquisition  Loan  described  herein,  the  Borrowers are in
compliance with all of the

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provisions  of Section  8.04 of the  Financing  Agreement,  and that no Event of
Default has occurred or is continuing immediately prior to or upon the execution
of this Agreement.

     8. Conditions Precedent.  This Agreement shall become effective on the date
the Lender receives the following documents, each of which shall be satisfactory
in form and substance to the Lender in its sole and absolute discretion:

          (a) A fully  executed  Acquisition  Note in the  form of  Exhibit  A-1
     attached hereto in the principal amount of $2,000,000;

          (b)  Payment of the  Acquisition  Loan fee in the amount of $10,000 by
     the Borrowers;

          (c) A fully executed copy of the Administrative Claim Subordination;

          (d) True,  correct and complete copies of all documents being executed
     and delivered in connection with the acquisition of SMC;

          (e)  True,  correct  and  complete  copies  of  all  notes,   security
     agreements,  guaranties,  documents or other instruments  previously or now
     executed  and  delivered  by  SMC  and/or  the  Borrower  to  or  from  the
     Subordinated Creditors;

          (f) Proof that the  Borrowers  have paid all costs and expenses to the
     Lender in connection with this Agreement,  including but not limited to all
     the Lender's attorneys fees; and

          (g)  Such  other  information,   instruments,   opinions,   documents,
     certificates and reports as the Lender may deem necessary.

     9. Counterparts.  This Agreement may be executed in any number of duplicate
originals or counterparts, each of which duplicate original or counterpart shall
be deemed to be an original and all taken together shall  constitute one and the
same instrument.

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     10. Financing  Documents;  Governing Law; Etc. This Agreement is one of the
Financing Documents defined in the Financing Agreement and shall be governed and
construed in  accordance  with the laws of the  Commonwealth  of  Virginia.  The
headings and captions in this  Agreement are for the  convenience of the parties
only and are not a part of this Agreement.

     11.  Acknowledgments.  The  Borrowers  hereby  confirm  to the  Lender  the
enforceability and validity of each of the Financing Documents. In addition, the
Borrowers  hereby agree to the execution and delivery of this  Agreement and the
terms and provisions,  covenants or agreements contained in this Agreement shall
not in any manner release,  impair, lessen, modify, waive or otherwise limit the
joint and several  liability and obligations of the Borrowers under the terms of
any of the Financing  Documents,  except as otherwise  specifically set forth in
this   Agreement.   The   Borrowers   each   issue,   ratify  and   confirm  the
representations, warranties and covenants contained in the Financing Documents.

     12. Modifications. This Agreement may not be supplemented, changed, waived,
discharged,  terminated,  modified  or  amended,  except by  written  instrument
executed by the parties.

     13.  Full  Force and  Effect.  Except as  expressly  set forth  above,  the
provisions of the Financing  Agreement  shall  continue in full force and effect
and are hereby ratified and confirmed. A default under this Agreement shall be a
default  under the  Financing  Agreement.  This  Agreement  may be executed  and
delivered in any number of  counterparts,  all of which,  taken together,  shall
constitute  one  agreement  and any party hereto may execute  this  Agreement by
signing any counterpart.

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     IN WITNESS WHEREOF the parties hereto have signed and sealed this Agreement
on the day and year first above written.

WITNESS OR ATTEST:             VERSAR, INC.


/s/ Lula Fasold                By: /s/ Lawrence W. Sinnott            (SEAL)
--------------------------         --------------------------
                                   Name:  Lawrence W. Sinnott
                                   Title: V.P. and CFO

WITNESS OR ATTEST:             GEOMET TECHNOLOGIES, INC.


/s/ Lula Fasold                By: /s/ Lawrence W. Sinnott            (SEAL)
--------------------------         --------------------------
                                   Name:  Lawrence W. Sinnott
                                   Title: Treasurer


                               LENDER:

WITNESS:                       NATIONSBANK, N.A.


                               By:                                    (SEAL)
--------------------------         --------------------------
                                   Jennifer Lathrop
                                   Commercial Lending Officer


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