Exhibit 10.5


                                    GUARANTY



         This GUARANTY (this "Guaranty"),  dated as of May 7, 1999, by and among
the  Guarantors  identified  as such  on the  signature  page  hereof  (each,  a
"Guarantor"  and  collectively,  "Guarantors"),  and  GENERAL  ELECTRIC  CAPITAL
CORPORATION,  a New  York  corporation,  individually  and  as  agent  (in  such
capacity, "Agent") for itself and the lenders from time to time signatory to the
Credit Agreement hereinafter defined ("Lenders").

                              W I T N E S S E T H:
                              -------------------

         WHEREAS, pursuant to that certain Credit Agreement dated as of the date
hereof by and among  Guarantors,  the Persons named  therein as Credit  Parties,
Agent and the Persons  signatory  thereto  from time to time as Lenders (as from
time to time amended, restated,  supplemented or otherwise modified, the "Credit
Agreement")  Lenders  have  agreed to make Loans to, and incur  Letter of Credit
Obligations for the benefit of, Borrowers.

         WHEREAS, Guarantors are affiliates of each of the Borrowers and as such
will derive direct and indirect  economic  benefits from the making of the Loans
and other financial  accommodations provided to Borrowers pursuant to the Credit
Agreement; and

         WHEREAS,  in order to induce Agent and Lenders to enter into the Credit
Agreement and other Loan  Documents and to induce  Lenders to make the Loans and
to incur Letter of Credit  Obligations as provided for in the Credit  Agreement,
Guarantors have agreed to guarantee payment of the Obligations;

         NOW,  THEREFORE,  in  consideration  of the premises and the  covenants
hereinafter  contained,  and to induce  Lenders to  provide  the Loans and other
financial accommodations under the Credit Agreement, it is agreed as follows:

1.       DEFINITIONS.
         -----------

         Capitalized  terms used herein shall have the meanings assigned to them
in the Credit Agreement, unless otherwise defined herein.

         References to this "Guaranty"  shall mean this Guaranty,  including all
amendments,   modifications  and  supplements  and  any  annexes,  exhibits  and
schedules to any of the foregoing,  and shall refer to this Guaranty as the same
may be in effect at the time such reference becomes operative.

2.       THE GUARANTY.
         ------------

         2.1 Guaranty of  Guaranteed  Obligations  of Borrower.  Each  Guarantor
             -------------------------------------------------
hereby  jointly and severally  unconditionally  guarantees to Agent and Lenders,
and their respective successors,  endorsees, transferees and assigns, the prompt
payment  (whether  at  stated  maturity,   by  acceleration  or  otherwise)  and
performance  of  the  Obligations  of  Borrowers  (hereinafter  the  "Guaranteed
Obligations").  Guarantors agree that this Guaranty is a guaranty of payment and
performance  and not of  collection,  and  that  their  obligations  under  this
Guaranty  shall be primary,  absolute and  unconditional,  irrespective  of, and
unaffected by:








                  (a) the genuineness,  validity, regularity,  enforceability or
any future amendment of, or change in this Guaranty,  any other Loan Document or
any other  agreement,  document or  instrument  to which any Credit Party and/or
Guarantors are or may become a party;

                  (b) the absence of any action to enforce this  Guaranty or any
other  Loan  Document  or the waiver or consent  by Agent  and/or  Lenders  with
respect to any of the provisions thereof;

                  (c) the  existence,  value or  condition  of,  or  failure  to
perfect its Lien against,  any Collateral for the Guaranteed  Obligations or any
action,  or the absence of any action,  by Agent in respect thereof  (including,
without limitation, the release of any such security); or

                  (d)      the insolvency of any Credit Party; or

                  (e) any other action or  circumstances  which might  otherwise
constitute a legal or equitable discharge or defense of a surety or guarantor,

         it being  agreed by each  Guarantor  that its  obligations  under  this
Guaranty  shall not be discharged  until the  Termination  Date.  Each Guarantor
shall be regarded,  and shall be in the same position,  as principal debtor with
respect to the Guaranteed Obligations.  Each Guarantor agrees that any notice or
directive  given at any time to Agent which is  inconsistent  with the waiver in
the immediately  preceding sentence shall be null and void and may be ignored by
Agent and  Lenders,  and,  in  addition,  may not be  pleaded or  introduced  as
evidence in any  litigation  relating to this  Guaranty for the reason that such
pleading or  introduction  would be at variance  with the written  terms of this
Guaranty,  unless  Agent and  Lenders  have  specifically  agreed  otherwise  in
writing. It is agreed among each Guarantor, Agent and Lenders that the foregoing
waivers are of the essence of the transaction contemplated by the Loan Documents
and that,  but for this  Guaranty  and such  waivers,  Agent and  Lenders  would
decline to enter into the Credit Agreement.

         2.2  Demand  by Agent  or  Lenders.  In  addition  to the  terms of the
              -----------------------------
Guaranty  set  forth in  Section  2.1  hereof,  and in no  manner  imposing  any
limitation on such terms, it is expressly understood and agreed that, if, at any
time, the outstanding  principal amount of the Guaranteed  Obligations under the
Credit  Agreement  (including  all accrued  interest  thereon) is declared to be
immediately due and payable,  then Guarantors shall,  without demand, pay to the
holders  of  the  Guaranteed   Obligations  the  entire  outstanding  Guaranteed
Obligations due and owing to such holders.  Payment by Guarantors  shall be made
to Agent in  immediately  available  Federal  funds to an account  designated by
Agent or at the address set forth herein for the giving of notice to Agent or at
any other  address  that may be specified in writing from time to time by Agent,
and shall be credited and applied to the Guaranteed Obligations.

         2.3  Enforcement  of  Guaranty.  In  no  event  shall  Agent  have  any
              -------------------------
obligation  (although  it is  entitled,  at its  option) to proceed  against any
Borrower  or  any  other  Credit  Party  or any  Collateral  pledged  to  secure
Guaranteed  Obligations  before  seeking  satisfaction  from  any  or all of the
Guarantors,  and Agent may proceed,  prior or subsequent  to, or  simultaneously
with,  the  enforcement of Agent's  rights  hereunder,  to exercise any right or
remedy which it may have against any Collateral,  as a result of any Lien it may
have as security for all or any portion of the Guaranteed Obligations.

         2.4 Waiver. In addition to the waivers contained in Section 2.1 hereof,
             ------
Guarantors  waive,  and agree that they shall not at any time insist upon, plead
or in any  manner  whatever  claim or take the  benefit  or  advantage  of,  any
appraisal,  valuation, stay, extension, marshaling of assets or redemption laws,
or exemption,  whether now or at any time  hereafter in force,  which may delay,
prevent or otherwise  affect the  performance by Guarantors of their  Guaranteed
Obligations  under,  or the  enforcement  by Agent or Lenders of, this Guaranty.
Guarantors   hereby  waive  diligence,   presentment  and  demand  (whether  for
non-payment or protest or of acceptance,  maturity, extension of time, change in
                                                    




nature or form of the Guaranteed  Obligations,  acceptance of further  security,
release of further security, composition or agreement arrived at as to the 
amount of, or the terms of,  the  Guaranteed  Obligations,  notice  of  adverse
change in any Borrower's  financial  condition or any other fact which might
increase the risk to Guarantors)  with respect to any of the  Guaranteed  
Obligations or all other demands  whatsoever  and waive the benefit of all
provisions of law which are or might be in  conflict  with the terms of this  
Guaranty.  Guarantors  represent, warrant and jointly and severally  agree that,
as of the date of this  Guaranty, their obligations under this Guaranty are not
subject to any offsets or defenses against  Agent or Lenders or any Credit 
Party of any kind.  Guarantors  further jointly and severally agree that their 
obligations under this Guaranty shall not be subject to any counterclaims, 
offsets or defenses against Agent or any Lender or against any Credit Party of
any kind which may arise in the future.

         2.5 Benefit of Guaranty.  The  provisions  of this Guaranty are for the
             -------------------
benefit  of Agent and  Lenders  and their  respective  successors,  transferees,
endorsees and assigns, and nothing herein contained shall impair, as between any
Credit Party and Agent or Lenders, the obligations of any Credit Party under the
Loan Documents.  In the event all or any part of the Guaranteed  Obligations are
transferred,  indorsed  or  assigned  by Agent or any  Lender  to any  Person or
Persons,  any  reference to "Agent" or "Lender"  herein shall be deemed to refer
equally to such Person or Persons.

         2.6 Modification of Guaranteed Obligations,  Etc. Each Guarantor hereby
             --------------------------------------------
acknowledges  and agrees  that Agent and Lenders may at any time or from time to
time, with or without the consent of, or notice to, Guarantors or any of them:

                  (a)      change or extend the manner, place or terms of 
payment of, or renew or alter all or any portion of, the Guaranteed Obligations;

                  (b) take any action under or in respect of the Loan  Documents
in the exercise of any remedy, power or privilege contained therein or available
to it at law, equity or otherwise,  or waive or refrain from exercising any such
remedies, powers or privileges;

                  (c)      amend or modify, in any manner whatsoever, the Loan
Documents;

                  (d)  extend  or  waive  the  time  for  any   Credit   Party's
performance of, or compliance with, any term,  covenant or agreement on its part
to be performed or observed under the Loan Documents,  or waive such performance
or compliance or consent to a failure of, or departure from, such performance or
compliance;

                  (e) take and hold Collateral for the payment of the Guaranteed
Obligations  guaranteed  hereby  or sell,  exchange,  release,  dispose  of,  or
otherwise deal with, any property  pledged,  mortgaged or conveyed,  or in which
Agent or Lenders have been granted a Lien, to secure any Obligations;

                  (f)  release  anyone  who may be liable in any  manner for the
payment of any amounts  owed by  Guarantors  or any Credit Party to Agent or any
Lender;

                  (g)  modify or  terminate  the terms of any  intercreditor  or
subordination  agreement  pursuant  to which  claims of other  creditors  of any
Guarantor  or any  Credit  Party  are  subordinated  to the  claims of Agent and
Lenders; and/or

                  (h) apply any sums by whomever paid or however realized to any
amounts  owing by any  Guarantor  or any Credit  Party to Agent or any Lender in
such manner as Agent or any Lender shall determine in its discretion;





and Agent and Lenders  shall not incur any  liability to  Guarantors as a result
thereof,  and no such action shall impair or release the Guaranteed  Obligations
of Guarantors or any of them under this Guaranty.

         2.7 Reinstatement.  This Guaranty shall remain in full force and effect
             -------------
and  continue  to be  effective  should any  petition be filed by or against any
Credit Party or any  Guarantor for  liquidation  or  reorganization,  should any
Credit Party or any Guarantor  become  insolvent or make an  assignment  for the
benefit of creditors or should a receiver or trustee be appointed for all or any
significant  part of such Credit Party's or such Guarantor's  assets,  and shall
continue to be  effective or be  reinstated,  as the case may be, if at any time
payment and performance of the Guaranteed Obligations,  or any part thereof, is,
pursuant to applicable law, rescinded or reduced in amount, or must otherwise be
restored or returned by Agent or any Lender, whether as a "voidable preference",
"fraudulent conveyance", or otherwise, all as though such payment or performance
had not been  made.  In the event  that any  payment,  or any part  thereof,  is
rescinded,  reduced,  restored or returned,  the Guaranteed Obligations shall be
reinstated  and deemed  reduced  only by such amount paid and not so  rescinded,
reduced, restored or returned.

         2.8  Deferral  of  Subrogation,  Etc.  Notwithstanding  anything to the
              -------------------------------
contrary in this Guaranty, or in any other Loan Document, each Guarantor hereby:

                  (a) expressly and irrevocably  waives, on behalf of itself and
its successors and assigns  (including any surety) until the  Termination  Date,
any and all  rights at law or in equity to  subrogation,  to  reimbursement,  to
exoneration,  to contribution,  to  indemnification,  to set off or to any other
rights that could accrue to a surety against a principal, to a guarantor against
a  principal,  to a guarantor  against a maker or obligor,  to an  accommodation
party against the party accommodated, to a holder or transferee against a maker,
or to the holder of any claim against any Person,  and which such  Guarantor may
have or hereafter  acquire  against any Credit Party in connection  with or as a
result  of such  Guarantor's  execution,  delivery  and/or  performance  of this
Guaranty,  or any  other  documents  to  which  such  Guarantor  is a  party  or
otherwise; and

                  (b)  acknowledges  and agrees (i) that this waiver is intended
to  benefit  Agent and  Lenders  and shall not  limit or  otherwise  effect  any
Guarantor's liability hereunder or the enforceability of this Guaranty, and (ii)
that Agent,  Lenders and their  respective  successors  and assigns are intended
third  party  beneficiaries  of the  waivers  and  agreements  set forth in this
Section 2.8 and their  rights under this  Section 2.8 shall  survive  payment in
full of the Guaranteed Obligations.

         2.9 Election of Remedies.  If Agent may, under  applicable law, proceed
             --------------------
to realize  benefits under any of the Loan Documents  giving Agent and Lenders a
Lien  upon  any  Collateral  owned  by any  Credit  Party,  either  by  judicial
foreclosure  or by  non-judicial  sale or  enforcement,  Agent may,  at its sole
option,  determine  which of such  remedies  or  rights  it may  pursue  without
affecting  any of such  rights  and  remedies  under this  Guaranty.  If, in the
exercise  of any of its rights and  remedies,  Agent  shall  forfeit  any of its
rights or remedies,  including its right to enter a deficiency  judgment against
any Credit Party, whether because of any applicable laws pertaining to "election
of remedies" or the like,  Guarantors hereby consent to such action by Agent and
waive any claim  based  upon such  action,  even if such  action by Agent  shall
result in a full or partial loss of any rights of subrogation  which  Guarantors
might otherwise have had but for such action by Agent.  Any election of remedies
which  results  in the  denial  or  impairment  of the  right of Agent to seek a
deficiency  judgment  against any Credit Party shall not impair each Guarantor's
obligation to pay the full amount of the  Guaranteed  Obligations.  In the event
Agent shall bid at any  foreclosure  or  trustee's  sale or at any private  sale
permitted  by law or the  Loan  Documents,  Agent  may bid all or less  than the
amount of the Guaranteed Obligations and the amount of such bid need not be paid
by Agent but shall be credited against the Guaranteed Obligations. The amount of
the successful bid at any such sale shall be conclusively  deemed to be the fair
market value of the collateral  and the  difference  between such bid amount and
the remaining balance of the Guaranteed Obligations shall be conclusively deemed
to be the amount of the Guaranteed  Obligations  guaranteed under this Guaranty,
notwithstanding  that any present or future law or court  decision or ruling may




have the effect of reducing  the amount of any  deficiency  claim to which Agent
and Lenders might otherwise be entitled but for such bidding at any such sale.

         2.10 Funds Transfers.  If any Guarantor shall engage in any transaction
              ---------------
as a result of which any  Borrower is  required  to make a mandatory  prepayment
with  respect  to the  Guaranteed  Obligations  under  the  terms of the  Credit
Agreement  (including any issuance or sale of such Guarantor's Stock or any sale
of its assets),  such Guarantor  shall  distribute to, or make a contribution to
the capital of, one or more of the  Borrowers an amount  equal to the  mandatory
prepayment required under the terms of the Credit Agreement.

3.       DELIVERIES.
         ----------

         In a form  satisfactory  to Agent,  Guarantors  shall  deliver to Agent
(with  sufficient  copies for each Lender),  concurrently  with the execution of
this  Guaranty  and  the  Credit   Agreement,   the  Loan  Documents  and  other
instruments,  certificates  and  documents  as are  required to be  delivered by
Guarantors to Agent under the Credit Agreement.

4.       REPRESENTATIONS AND WARRANTIES.
         ------------------------------

         To  induce  Lenders  to make the  Loans  and  incur  Letter  of  Credit
Obligations  under the Credit Agreement,  Guarantors  jointly and severally make
the  representations and warranties as to each Guarantor contained in the Credit
Agreement,  each of which is incorporated herein by reference, and the following
representations  and warranties to Agent and each Lender,  each and all of which
shall survive the execution and delivery of this Guaranty:

         4.1 Corporate  Existence;  Compliance with Law. Each Guarantor (i) is a
             ------------------------------------------
corporation duly organized, validly existing and in good standing under the laws
of its jurisdiction of incorporation;  (ii) is duly qualified to do business and
is in good standing under the laws of each  jurisdiction  where its ownership or
lease of property or the conduct of its business  requires  such  qualification;
(iii) has the  requisite  corporate  power and  authority and the legal right to
own,  pledge,  mortgage  and operate its  properties,  to lease the  property it
operates  under  lease,  and to conduct  its  business  as now,  heretofore  and
proposed to be conducted; (iv) has all licenses,  permits, consents or approvals
from or by, and has made all material  filings  with,  and has given all notices
to, all Governmental Authorities having jurisdiction, to the extent required for
such ownership, operation and conduct; (v) is in compliance with its charter and
by-laws; and (vi) is in compliance with all applicable provisions of law, except
where  the  failure  to  comply,  individually  or in the  aggregate,  could not
reasonably be expected to have a Material Adverse Effect.

         4.2 Executive Offices.  Each Guarantor's executive office and principal
             -----------------
place of business are as set forth in  Disclosure  Schedule  (3.2) of the Credit
                                       ---------------------------
Agreement.

         4.3 Corporate Power; Authorization; Enforceable Guaranteed Obligations.
             ------------------------------------------------------------------
The  execution,  delivery and  performance  of this  Guaranty and all other Loan
Documents and all  instruments  and documents to be delivered by each  Guarantor
hereunder and under the Credit Agreement are within such  Guarantor's  corporate
power,  have been duly authorized by all necessary or proper  corporate  action,
including the consent of stockholders  where required,  are not in contravention
of any provision of such Guarantor's  charter or by-laws, do not violate any law
or  regulation,  or any order or decree of any  Governmental  Authority,  do not
conflict  with or result in the breach of, or  constitute  a default  under,  or
accelerate  or permit  the  acceleration  of any  performance  required  by, any
indenture,  mortgage,  deed of trust,  lease,  agreement or other  instrument to
which any  Guarantor is a party or by which any Guarantor or any of its property
is bound,  do not result in the creation or  imposition  of any Lien upon any of
the property of any  Guarantor,  other than those in favor of Agent,  for itself
and the benefit of Lenders,  and the same do not require the consent or approval
of any  Governmental  Authority or any other Person except those  referred to in
Section  2.1(c) of the Credit  Agreement,  all of which have been duly obtained,
made or  complied  with prior to the  Closing  Date.  On or prior to the Closing
Date,  this Guaranty and each of the Loan  Documents to which any Guarantor is a







party shall have been duly executed and delivered for the benefit of or on 
behalf of such Guarantor,  and each shall then constitute a legal, valid and
binding obligation of such Guarantor,  enforceable against such Guarantor in 
accordance with its terms.

5.       FURTHER ASSURANCES.
         ------------------

         Each Guarantor agrees, upon the written request of Agent or any Lender,
to  execute  and  deliver  to  Agent or such  Lender,  from  time to  time,  any
additional  instruments or documents reasonably considered necessary by Agent or
such Lender to cause this  Guaranty to be,  become or remain valid and effective
in accordance with its terms.

6.       PAYMENTS FREE AND CLEAR OF TAXES.
         --------------------------------

         All payments  required to be made by each Guarantor  hereunder shall be
made to Agent and Lenders free and clear of, and without  deduction for, any and
all  present  and future  Taxes.  If any  Guarantor  shall be required by law to
deduct any Taxes from or in respect of any sum  payable  hereunder,  (a) the sum
payable  shall be  increased  as much as shall be necessary so that after making
all required  deductions  (including  deductions  applicable to additional  sums
payable under this Section 6) Agent or Lenders, as applicable, receive an amount
equal to the sum they would have received had no such  deductions been made, (b)
such Guarantor shall make such deductions,  and (c) such Guarantor shall pay the
full amount  deducted to the relevant  taxing or other  authority in  accordance
with  applicable  law.  Within thirty (30) days after the date of any payment of
Taxes,  each  applicable  Guarantor  shall  furnish to Agent the  original  or a
certified copy of a receipt  evidencing  payment  thereof.  Each Guarantor shall
jointly and severally  indemnify and,  within ten (10) days of demand  therefor,
pay Agent and each  Lender  for the full  amount of Taxes  (including  any Taxes
imposed by any  jurisdiction  on amounts  payable  under this Section 6) paid by
Agent or such Lender, as appropriate,  and any liability  (including  penalties,
interest and expenses) arising therefrom or with respect thereto, whether or not
such Taxes were correctly or legally asserted.

7.       OTHER TERMS.
         -----------

         7.1  Entire  Agreement.  This  Guaranty,  together  with the other Loan
              -----------------
Documents,  constitutes the entire agreement between the parties with respect to
the subject  matter hereof and  supersedes  all prior  agreements  relating to a
guaranty  of the  loans  and  advances  under  the  Loan  Documents  and/or  the
Guaranteed Obligations.

         7.2  Headings.  The headings in this  Guaranty are for  convenience  of
              --------
reference only and are not part of the substance of this Guaranty.

         7.3 Severability.  Whenever  possible,  each provision of this Guaranty
             ------------
shall be interpreted in such a manner to be effective and valid under applicable
law, but if any  provision of this  Guaranty  shall be  prohibited by or invalid
under  applicable law, such provision shall be ineffective to the extent of such
prohibition or invalidity,  without invalidating the remainder of such provision
or the remaining provisions of this Guaranty.

         7.4 Notices.  Whenever it is provided  herein that any notice,  demand,
             -------
request, consent,  approval,  declaration or other communication shall or may be
given to or served upon any of the parties by any other  party,  or whenever any
of the parties desires to give or serve upon another any such communication with
respect to this Guaranty, each such notice, demand, request, consent,  approval,
declaration or other communication shall be in writing and shall be addressed to
the party to be notified as follows:








                  (a)      If to Agent, at:

                           GENERAL ELECTRIC CAPITAL CORPORATION
                           201 High Ridge Road
                           Stamford, Connecticut 06927
                           Attention:       American Eco Account Manager
                           Telecopier:      203 316-7893
                           Telephone:       203 316-7500

                  with copies to:

                           OTTERBOURG, STEINDLER, HOUSTON & ROSEN, P.C.
                           230 Park Avenue
                           New York, New York 10169
                           Attention:       Mitchell M. Brand, Esq.
                           Telecopier:      212 682-6104
                           Telephone:       212 661-9100

                  (b) If to any Lender,  at the address of such Lender specified
in the Credit Agreement.

                  (c) If to any  Guarantor,  at the  address  of such  Guarantor
specified on Schedule I hereto.
             ----------

or at such  other  address  as may be  substituted  by  notice  given as  herein
provided.  The giving of any notice required  hereunder may be waived in writing
by the party  entitled to receive such notice.  Every notice,  demand,  request,
consent, approval,  declaration or other communication hereunder shall be deemed
to have been validly  served,  given or delivered (i) upon the earlier of actual
receipt  and three (3)  Business  Days after the same shall have been  deposited
with the United  States mail,  registered  or  certified  mail,  return  receipt
requested,  with proper postage prepaid,  (ii) upon  transmission,  when sent by
telecopy  or  other  similar  facsimile  transmission  (with  such  telecopy  or
facsimile  promptly  confirmed  by delivery  of a copy by  personal  delivery or
United  States mail as otherwise  provided in this Section  7.4),  (iii) one (1)
                                                   ------------
Business Day after deposit with a reputable  overnight  carrier with all charges
prepaid, or (iv) when delivered, if hand-delivered by messenger.

         7.5  Successors  and  Assigns.  This  Guaranty and all  obligations  of
              ------------------------
Guarantors  hereunder  shall be binding upon the  successors and assigns of each
Guarantor  (including a  debtor-in-possession  on behalf of such  Guarantor) and
shall,  together  with the rights and remedies of Agent,  for itself and for the
benefit of Lenders,  hereunder,  inure to the benefit of Agent and Lenders,  all
future holders of any instrument  evidencing  any of the  Obligations  and their
respective  successors  and assigns.  No sales of  participations,  other sales,
assignments,  transfers  or other  dispositions  of any  agreement  governing or
instrument evidencing the Obligations or any portion thereof or interest therein
shall in any manner affect the rights of Agent and Lenders hereunder. Guarantors
may not assign,  sell,  hypothecate  or  otherwise  transfer  any interest in or
obligation under this Guaranty.

         7.6 No Waiver; Cumulative Remedies;  Amendments.  Neither Agent nor any
             -------------------------------------------
Lender shall by any act,  delay,  omission or otherwise be deemed to have waived
any of its rights or remedies hereunder,  and no waiver shall be valid unless in
writing, signed by Agent and then only to the extent therein set forth. A waiver
by Agent, for itself and the ratable benefit of Lenders,  of any right or remedy
hereunder  on any one  occasion  shall not be construed as a bar to any right or
remedy which Agent would otherwise have had on any future  occasion.  No failure
to exercise nor any delay in exercising on the part of Agent or any Lender,  any
right,  power or privilege  hereunder,  shall operate as a waiver  thereof,  nor
shall any single or partial exercise of any right, power or privilege  hereunder
preclude  any other or future  exercise  thereof  or the  exercise  of any other
right,  power or  privilege.  The rights and  remedies  hereunder  provided  are
cumulative and may be exercised singly or concurrently, and are not exclusive of







any rights and remedies provided by law. None of the terms or provisions of this
Guaranty may be waived,  altered,  modified,  supplemented or amended except by
an instrument in writing, duly executed by Agent and Guarantors.

         7.7  Termination.  This  Guaranty is a  continuing  guaranty  and shall
              -----------
remain in full force and effect  until the  Termination  Date.  Upon payment and
performance  in full of the  Guaranteed  Obligations,  Agent  shall  deliver  to
Guarantors such documents as Guarantors may reasonably  request to evidence such
termination.

         7.8  Counterparts.  This  Guaranty  may be  executed  in any  number of
              ------------
counterparts, each of which shall collectively and separately constitute one and
the same agreement.

         7.9      GOVERNING LAW; CONSENT TO JURISDICTION AND VENUE.
                  ------------------------------------------------

         EXCEPT AS OTHERWISE EXPRESSLY PROVIDED IN ANY OF THE LOAN DOCUMENTS, IN
ALL RESPECTS,  INCLUDING ALL MATTERS OF CONSTRUCTION,  VALIDITY AND PERFORMANCE,
THIS GUARANTY AND THE  OBLIGATIONS  ARISING  HEREUNDER SHALL BE GOVERNED BY, AND
CONSTRUED  AND ENFORCED IN  ACCORDANCE  WITH,  THE LAWS OF THE STATE OF NEW YORK
APPLICABLE  TO CONTRACTS  MADE AND PERFORMED IN SUCH STATE,  AND ANY  APPLICABLE
LAWS OF THE UNITED STATES OF AMERICA.  EACH GUARANTOR HEREBY CONSENTS AND AGREES
THAT THE STATE OR  FEDERAL  COURTS  LOCATED IN NEW YORK,  SHALL  HAVE  EXCLUSIVE
JURISDICTION  TO HEAR AND  DETERMINE  ANY  CLAIMS OR  DISPUTES  BETWEEN OR AMONG
GUARANTORS,  AGENT OR ANY LENDER  PERTAINING  TO THIS  GUARANTY OR TO ANY MATTER
ARISING OUT OF OR RELATING TO THIS GUARANTY OR ANY OF THE OTHER LOAN  DOCUMENTS,
PROVIDED,  THAT AGENT AND  GUARANTORS  ACKNOWLEDGE  THAT ANY APPEALS  FROM THOSE
COURTS  MAY  HAVE TO BE HEARD  BY A COURT  LOCATED  OUTSIDE  OF NEW  YORK,  AND,
PROVIDED,  FURTHER,  THAT NOTHING IN THIS GUARANTY SHALL BE DEEMED OR OPERATE TO
PRECLUDE  AGENT FROM  BRINGING  SUIT OR TAKING  OTHER LEGAL  ACTION IN ANY OTHER
JURISDICTION  TO  REALIZE  ON THE  COLLATERAL  OR ANY  OTHER  SECURITY  FOR  THE
GUARANTEED  OBLIGATIONS,  OR TO ENFORCE A JUDGMENT OR OTHER COURT ORDER IN FAVOR
OF AGENT, FOR THE BENEFIT OF AGENT AND LENDERS. EACH GUARANTOR EXPRESSLY SUBMITS
AND CONSENTS IN ADVANCE TO SUCH  JURISDICTION IN ANY ACTION OR SUIT COMMENCED IN
ANY SUCH COURT, AND EACH GUARANTOR HEREBY WAIVES ANY OBJECTION WHICH IT MAY HAVE
BASED UPON LACK OF PERSONAL JURISDICTION, IMPROPER VENUE OR FORUM NON CONVENIENS
AND HEREBY  CONSENTS  TO THE  GRANTING OF SUCH LEGAL OR  EQUITABLE  RELIEF AS IS
DEEMED  APPROPRIATE BY SUCH COURT. EACH GUARANTOR HEREBY WAIVES PERSONAL SERVICE
OF THE SUMMONS,  COMPLAINT AND OTHER  PROCESS  ISSUED IN ANY SUCH ACTION OR SUIT
AND AGREES THAT SERVICE OF SUCH  SUMMONS,  COMPLAINTS  AND OTHER  PROCESS MAY BE
MADE BY REGISTERED OR CERTIFIED  MAIL ADDRESSED TO SUCH GUARANTOR AT THE ADDRESS
SET  FORTH  ON  SCHEDULE  I HERETO  AND THAT  SERVICE  SO MADE  SHALL BE  DEEMED
                -----------
COMPLETED  UPON THE  EARLIER OF ACTUAL  RECEIPT  THEREOF OR THREE (3) DAYS AFTER
DEPOSIT IN THE U.S. MAILS, PROPER POSTAGE PREPAID.

         7.10     WAIVER OF JURY TRIAL.
                  --------------------

         BECAUSE   DISPUTES   ARISING  IN  CONNECTION  WITH  COMPLEX   FINANCIAL
TRANSACTIONS  ARE MOST QUICKLY AND  ECONOMICALLY  RESOLVED BY AN EXPERIENCED AND
EXPERT  PERSON AND THE PARTIES WISH  APPLICABLE  STATE AND FEDERAL LAWS TO APPLY
(RATHER THAN ARBITRATION  RULES), EACH GUARANTOR AND AGENT DESIRES THAT DISPUTES
ARISING  HEREUNDER  OR  RELATING  HERETO BE RESOLVED  BY A JUDGE  APPLYING  SUCH
APPLICABLE LAWS.  THEREFORE,  TO ACHIEVE THE BEST COMBINATION OF THE BENEFITS OF
THE JUDICIAL  SYSTEM AND OR  ARBITRATION,  EACH  GUARANTOR  AND AGENT WAIVES ALL







RIGHTS TO TRIAL BY JURY IN ANY ACTION, SUIT OR PROCEEDING BROUGHT TO RESOLVE ANY
DISPUTE, WHETHER SOUNDING IN  CONTRACT,  TORT,  OR  OTHERWISE,  ARISING OUT OF,
CONNECTED  WITH, RELATED TO, OR INCIDENTAL TO THE  RELATIONSHIP  ESTABLISHED  
IN CONNECTION  WITH THIS GUARANTY AND THE OTHER LOAN DOCUMENTS OR THE 
TRANSACTIONS RELATED HERETO OR THERETO.

         7.11  Limitation  on  Guaranteed   Obligations.   Notwithstanding   any
               ----------------------------------------
provision herein contained to the contrary, each Guarantor's liability hereunder
shall be limited to an amount not to exceed as of any date of determination  the
greater of:

         (a)  the net  amount  of all  Loans  and  other  extensions  of  credit
(including  Letters of Credit)  advanced under the Credit Agreement and directly
or indirectly re-loaned or otherwise transferred to, or incurred for the benefit
of, such  Guarantor,  plus interest  thereon at the applicable rate specified in
the Credit Agreement; or

         (b) the amount  which  could be claimed by the Agent and  Lenders  from
such  Guarantor  under this Guaranty  without  rendering  such claim voidable or
avoidable  under Section 548 of Chapter 11 of the  Bankruptcy  Code or under any
applicable state Uniform Fraudulent Transfer Act, Uniform Fraudulent  Conveyance
Act or similar  statute or common law after  taking  into  account,  among other
things,  such Guarantor's  right of contribution and  indemnification  from each
other Guarantor under Section 7.12.

         7.12     Contribution with Respect to Guaranteed Obligations.
                  ---------------------------------------------------

         (a) To the extent that any  Guarantor  shall make a payment  under this
Guaranty of all or any of the  Guaranteed  Obligations  (a "Guarantor  Payment")
which,  taking into account all other  Guarantor  Payments  then  previously  or
concurrently  made by the  other  Guarantors,  exceeds  the  amount  which  such
Guarantor  would  otherwise  have paid if each  Guarantor had paid the aggregate
Guaranteed   Obligations  satisfied  by  such  Guarantor  Payment  in  the  same
proportion  that such  Guarantor's  "Allocable  Amount" (as  defined  below) (in
effect  immediately  prior  to such  Guarantor  Payment)  bore to the  aggregate
Allocable Amounts of all of Guarantors in effect immediately prior to the making
of such Guarantor Payment,  then, following indefeasible payment in full in cash
of the Obligations and termination of the  Commitments,  such Guarantor shall be
entitled to receive  contribution  and  indemnification  payments  from,  and be
reimbursed by, each of the other  Guarantors for the amount of such excess,  pro
rata based upon their respective  Allocable Amounts in effect  immediately prior
to such Guarantor Payment.

         (b) As of any date of  determination,  the  "Allocable  Amount"  of any
Guarantor  shall be equal to the maximum amount of the claim which could then be
recovered from such Guarantor under this Guaranty  without  rendering such claim
voidable or avoidable  under Section 548 of Chapter 11 of the Bankruptcy Code or
under any applicable state Uniform  Fraudulent  Transfer Act, Uniform Fraudulent
Conveyance Act or similar statute or common law.

         (c) This Section 7.12 is intended only to define the relative rights of
                  ------------
Guarantors  and nothing set forth in this  Section  7.12 is intended to or shall
                                           -------------
impair the obligations of Guarantors,  jointly and severally, to pay any amounts
as and when the same shall become due and payable in  accordance  with the terms
of this Guaranty.

         (d) The  rights  of the  parties  under  this  Section  7.12  shall  be
                                                        -------------
exercisable upon the full and indefeasible payment of the Guaranteed Obligations
and the termination of the Credit Agreement and the other Loan Documents.

         (e) The parties hereto  acknowledge that the rights of contribution and
indemnification hereunder shall constitute assets of any Guarantor to which such
contribution and indemnification is owing.








8.       SECURITY.
         --------

         To secure payment of each Guarantor's  obligations under this Guaranty,
concurrently  with the execution of this  Guaranty,  each  Guarantor has entered
into a Security  Agreement pursuant to which each Guarantor has granted to Agent
for the  benefit  of  Lenders a security  interest  in  certain of its  personal
property as more particularly described in such Security Agreement.

9.       CREDIT AGREEMENT.
         ----------------

         Each  Guarantor  agrees to perform,  comply with and be bound by, among
other  covenants,  the covenants  contained in Sections 4, 5 and 6 of the Credit
Agreement.

         IN WITNESS WHEREOF, the parties hereto have executed and delivered this
Guaranty as of the date first above written.

                                 CAMBRIDGE CONSTRUCTION SERVICE CORP.
                                 H.E. CO. SERVICES, INC.
                                 INDUSTRA THERMAL SERVICE CORP.
                                 LAKE CHARLES CONSTRUCTION CORPORATION
                                 NUS, INC.
                                 SEPARATION AND RECOVERY SYSTEMS
                                  CALIFORNIA

                                 By:    /s/ David L. Norris
                                       -----------------------------------------
                                 Name:      David L. Norris
                                       -----------------------------------------
                                 Title:     Vice President              Of Each
                                       -----------------------------------------

                                 GENERAL ELECTRIC CAPITAL CORPORATION,
                                  as Agent

                                 By:    /s/ Charles D. Chiodo
                                       -----------------------------------------
                                 Name:      Charles D. Chiodo
                                       -----------------------------------------
                                 Title:     Duly Authorized Signatory  
                                       -----------------------------------------