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                                                                    Exhibit 10.1

                        TERMINATION AND WAIVER OF CLAIMS

WHEREAS, NEI of Pennsylvania, Inc., as Buyer ("NEI or Buyer") and NYTEST
Environmental Inc., its parent corporation ("NYTEST"), entered into a contract
with BCM Engineers Inc., a Pennsylvania corporation ("BCM") and Smith
Technology Corporation ("SMITH") to the extent set forth in Section 7, for the
purchase of certain assets and the assumption by NEI of certain leases and
liabilities dated August 3, 1995, (the "Asset Agreement"), and

WHEREAS, NEI, pursuant to the Asset Agreement, entered into a sublease dated
August 3, 1995, of a portion of the improved real property leased by BCM from
the Gravers Company at 1850 Gravers Road in Norristown, Pennsylvania, commonly
referred to as the Laboratory Site (the "Sublease"), and

WHEREAS, NEI entered into two subleases dated August 3, 1995, of personal
property wherein NEI assumed the obligations of the lease of personal property
supplied through Fidelcor Services Inc. (the "Fidelcor Sublease"), and for
personal property obtained through Tokai Financial Services, Inc. (the "Tokai
Sublease"), and

WHEREAS, various disputes as to the rights and obligations of BCM and Smith
Technology Corporation ("Smith"), NEI and NYTEST have arisen and the parties
desire to resolve such disputes, NOW THEREFORE, the parties enter into this
agreement (the "Termination Agreement") as follows:

1.  Termination of Sublease

    The parties agree that the Sublease is terminated effective February 28,
    1997, and that NEI and NYTEST forego and waive all claims of any right,
    title, or interest in and to all fixtures, equipment, improvements,
    installations, and the appurtenances in each case attached to the sublet
    premises at commencement of the Sublease or which may have been attached
    during the term thereof. The costs, removal and disposal of regulated waste
    will be deducted from the amount due under paragraph 5.

2.  Termination of Fidelcor Sublease and Tokai Sublease

    The parties agree that the Fidelcor Sublease and the Tokai Sublease
    including all future sublease obligations are terminated effective February
    28, 1997, with  no continuing obligation as between the parties. NEI agrees
    that it is, as of March 10, 1997, in possession of all personal property and
    equipment to which it is entitled under the terms of the Asset Agreement.
    NEI and NYTEST waive any right or interest in and to any other property or
    equipment or proceeds of equipment leased or which may have been acquired
    under the terms of the Fidelcor Sublease and Tokai Sublease.

3.  NEI and NYTEST further agree that they waive all interest and any claim of
    title in and to the assets described in paragraph 1.1c of the Asset
    Agreement which remain at the Lab Site as of the date of this Agreement.

4.  Credits and Offsets

    BCM, NEI and NYTEST acknowledge that BCM has received laboratory services
    from NEI and its affiliated laboratories and that BCM has offset amounts
    owed by BCM and Smith for laboratory services and NEI, NYTEST and its
    affiliates have received credit for the amount of such offsets

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   against amounts owed by NEI to BCM pursuant to the terms of the Asset
   Agreement. The amount of such offset and credit is set forth as follows:

   Invoices for Services through February 28, 1997

   Hudson Chromate (the "Project")                 $692,847
   Other Services                                   589,963
                                                   --------

   Total for Services through February 28, 1997                    $1,282,810
   Less BCM Payments                                                  108,466
                                                                   ----------
   Balance for Services as of February 28, 1997                    $1,174,344

   Less Amounts due (offset) from NEI per
   Asset Agreement through May 31, 1996                            $  493,262

   Amount Due NEI                                                  $  681,082

5. Survivability of Claim

   Notwithstanding the reciprocal waiver and release of claims by the parties
   contained herein, the parties acknowledge that NYTEST has continued to
   perform laboratory services for BCM at its request related to the Hudson
   County Chromate Chemical Production Waste Site project (the "Project"). BCM
   agrees that it will continue to use NYTEST as NEI's successor for laboratory
   services at the Project on the basis of the contract for Laboratory Services
   dated September 14, 1995, between BCM, NYTEST and NEI, subject to the
   continued approval of the New Jersey Department of Environmental Protection
   (NJDEP) to use NEI or NYTEST.

   The parties agree that NYTEST's and NEI's total amounts billed for services
   identified in Section 4 above includes $692,847 relating to the Project and
   performed prior to February 28, 1997. This obligation is subject to NJDEP's
   approval and acceptance of NYTEST's analytical work, holding periods, and
   acknowledgment that the laboratory services are in compliance with the
   requirements of the NJDEP.

   NYTEST accepts $681,082 as identified in Section 4 above in complete
   satisfaction of amounts due for services rendered to February 28, 1997, and
   acknowledges that NYTEST shall be subject to backcharge for the amount of any
   services rejected by NJDEP due to actions or omissions by NYTEST and the cost
   of resampling and reperformance incurred as a result of such rejection. Any
   such backcharge shall be deducted from amounts due for future services and
   the retainage. 

   BCM and SMITH shall pay the balance due in installments on the dates set 
   forth below:

        Installment                             Payment
          Amount                                  Date
        -----------                     -----------------------------

         $681,082                       a payment schedule to be 
                                        mutually agreed upon by both
                                        parties is anticipated to be
                                        completed by April 18, 1997




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6. Waiver of Claims

        a. Waiver of NEI and NYTEST. For and in consideration of the promises
           and covenants set forth in this Termination Agreement, NYTEST and
           NEI, their successors, assigns and any and all persons claiming by,
           through or under them, hereby release and forever discharge BCM and
           its parent, subsidiaries, affiliates, predecessors, successors,
           related entities, directors, employees, agents, attorneys, and all
           persons acting by and through, under or in concert with them, or any
           of them, of and from any and all claims, demands, claims for relief,
           obligations, rights, and/or liabilities of any nature, whether
           anticipated or unanticipated, known or unknown, fixed or contingent,
           past or present (hereinafter referred to as "Claims"), which NYTEST
           and NEI now have or may hereafter have against BCM and its parent,
           subsidiaries, affiliates, predecessors, successors, related entities,
           insurers and assigns, as well as its past and present officers,
           directors, employees, agents, attorneys, and all persons acting by
           and through, under or in concert with them, or any of them, by reason
           of any matter, cause or thing arising out of, based upon, or relating
           to the Asset Agreement and as amended by Smith letter dated August
           22, 1996.

        b. Waiver of BCM. For and in consideration of the promises and covenants
           set forth in this Termination Agreement, BCM, its successors, assigns
           and any and all persons claiming through or under it, hereby releases
           and forever discharges NYTEST and NEI and its parents, subsidiaries,
           affiliates, predecessors, successors, related entities, directors,
           employees, agents, attorneys, and all persons acting by and through,
           under or in concert with them, or any of them, of and from any and
           all claims, demands, claims for relief, obligations, rights, and/or
           liabilities of any nature, whether anticipated or unanticipated,
           known or unknown, fixed or contingent, past or present (hereinafter
           referred to as "Claims"), which BCM now has or may hereafter have
           against NYTEST or NEI and its respective parent, subsidiaries,
           affiliates, predecessors, successors, related entities, insurers and
           assigns, as well as its past and present officers, directors,
           employees, agents, attorneys, and all persons acting by and through,
           under or in concert with them, or any of them, by reason of any
           matter, cause or thing arising out of, based upon, or relating to the
           Asset Agreement and as amended by Smith letter dated August 22, 1996.

        c. Non-Admission of Liability. This Termination Agreement and the
           releases and other terms provided for herein are made, executed,
           given and accepted as a part of a compromise and resolution of
           disputed claims. No provision(s) of the Termination Agreement, nor
           the parties hereto, shall be construed or deemed to be evidence of an
           admission of any fact, matter, thing or liability of any kind to any
           other party. Each of the parties hereto denies any liability of any
           kind to the other party for any purpose, and this Termination
           Agreement is made solely and entirely as a compromise and for the
           purpose of fully and finally resolving the disputed matters referred
           to herein. Neither the Termination Agreement nor any term thereof
           shall be offered or received as evidence in any proceeding in any
           forum as an admission of any liability or wrongdoing on the part of
           any of the parties hereto.

        d. No Assignment. Each party represents and warrants that there has been
           no assignment or other transfer to any other person, firm or
           corporation in any manner, including by way of subrogation or
           operation of law or otherwise, of all or any portion of any claim,
           demand, right, action or claim for relief that it had, has or might
           have arising out of the matters released in the Termination
           Agreement, nor of all or any portion of any claim, suit, recovery or
           settlement to which it may be entitled. In the event that any claim,
           demand or suit should be made or instituted against a party because
           of any such purported assignment, subrogation or transfer, each party
           agrees to indemnify and hold the other party harmless against such
           claims, demand, or suit, together with any costs, 



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        expenses and attorneys' fees incurred by the other party as a result of
        any person's assertion of any such assignment or transfer.


7. Smith Technology corporation has entered into this Agreement solely for the
   purpose of participating as a party to the extent of the waiver of claims
   provided the parties herein and for the purpose of acknowledging the offsets
   and credits agreed to herein and to the extent of guarantee agreements as
   provided in Article 5.16 of the Asset Agreement.


This Agreement is effective as of the date of the last party to sign.


Date:   4/19/97                         NEI OF PENNSYLVANIA, INC.



                                        By:  /s/ John Gaspari
                                           -----------------------------
                                        Its: President
                                            ----------------------------


Date:   4/14/97                         NYTEST ENVIRONMENTAL INC.



                                        By:  /s/ John Gaspari
                                           -----------------------------
                                        Its: President & CEO
                                            ----------------------------


Date:   4/11/97                         BCM ENGINEERS INC.



                                        By:  /s/ Robert Swavely
                                           -----------------------------
                                        Its: Vice President
                                            ----------------------------


Date:   4/11/97                         SMITH TECHNOLOGY CORPORATION



                                        By:  /s/ William Nelson
                                           -----------------------------
                                        Its: Vice President
                                            ----------------------------






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