EXHIBIT 10.23

                                LEASE AGREEMENT


         THIS LEASE,  dated this 4th day of April,  1997 for reference  purposes
only, is made and entered into by and between  EMCON,  a California  corporation
("Landlord") and Columbia Analytical  Services,  Inc., a Washington  corporation
("Tenant").

         Landlord and Tenant agree to the terms,  covenants  and  conditions  of
this Lease, as follows:






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1.  PREMISES.  Landlord  hereby  leases to Tenant and Tenant  hereby leases from
Landlord those certain premises (the "Premises") described on the Lease Summary.
The term  "Buildings"  as used  herein  shall mean the entire  laboratories  and
administrative  buildings  more  particularly  described  in  Exhibit A attached
hereto.  The term "Property" shall mean and include all of the area described in
Exhibit "A" attached hereto and all of the buildings, improvements, fixtures and
equipment now or hereafter situated thereon.

2. USE. 

        2.1 Permitted Uses. Tenant shall use the Premises solely for the purpose
stated on the Lease Summary and for no other purpose.

        2.2 Compliance with Law.  Tenant shall, at Tenant's sole cost,  promptly
comply  with  all  laws,  ordinances,   codes,  rules,  orders,  directives  and
regulations of governmental authority (collectively, "Governmental Regulations")
regulating  the condition,  use or occupancy of the Premises,  including but not
limited  to,  any  alterations,   additions  or   modifications   (collectively,
"Alterations") to the Premises required by Governmental Regulations.

        2.3  Restriction  on Use.  Tenant shall not use or permit the use of the
Premises  in any  manner  that  will  tend to create  waste on the  Premises  or
constitute  a nuisance  to any other  occupant or user of the  Buildings  or the
Property or any property adjacent thereto or do or keep anything that will cause
cancellation of or an increase in rates of any insurance covering the Buildings.
Tenant shall not use any apparatus, machinery or other equipment in or about the
Premises  that may cause  substantial  noise or vibration  or overload  existing
electrical  systems,  and shall not place any loads upon the floors,  walls,  or
ceilings of the Premises which may  jeopardize  the structural  integrity of the
Buildings or any part  thereof.  Tenant shall not make any  penetrations  of the
roof or exterior of the  Buildings or attach any  antennas or equipment  thereon
without the prior written  approval of Landlord  which will not be  unreasonably
withheld.  Any  penetrations  of the roof allowed by Landlord  shall be properly
flashed and caulked and shall be removed  and the roof  membrane  restored  upon
expiration  of the Lease term.  No  materials or articles of any nature shall be
stored  outside  the  Premises,   unless  in  compliance   with  any  applicable
Governmental Regulations.

        2.4 Hazardous Materials

                A. Definitions.  As used herein, the term "Hazardous Material" -
shall mean any substance:  (i) the presence of which requires  investigation  or
remediation under any federal,  state or local statute,  regulation,  ordinance,
order,  action,  policy or common  law;  (ii) which is or  becomes  defined as a
"hazardous  waste,"  "hazardous  substance,"  pollutant or contaminant under any
federal,  state or local  statute,  regulation,  rule or ordinance or amendments
thereto including, without limitation, the Comprehensive Environmental Response,
Compensation  and  Liability  Act (42 U.S.C.  Section  9601 et seq.)  and/or the
Resource  Conservation and Recovery Act (42 U.S.C.  Section 6901 et seq.); (iii)
which  is  toxic,  explosive,  corrosive,  flammable,  infectious,  radioactive,
carcinogenic,  mutagenic,  or otherwise hazardous and is or becomes regulated by
any  governmental   authority,   department,   commission,   board,   agency  or
instrumentality  of the United States,  the State of Washington or any political
subdivision  thereof;  (iv)  the  presence  of which  on the  Premises  poses or
threatens to pose a known material risk to the health or safety of persons on or


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about the Premises; (v) without limitation which contains gasoline,  diesel fuel
or  other  petroleum  hydrocarbons;   (vi)  without  limitation  which  contains
polychlorinated biphenyls (PCBs), asbestos or urea formaldehyde foam insulation;
or (vii) without limitation radon gas.

                B.  Tenant  shall  not use,  analyze,  store,  dispose,  handle,
transport,  release,  discharge or generate any Hazardous  Materials in, on, to,
under,  from or about the Premises or Buildings,  except in accordance  with all
governmental laws, rules and regulations.

                C. Tenant shall not cause or permit any Hazardous Materials used
by Tenant to be discharged into the plumbing or sewage system of the Building or
onto the land underlying the Building or anywhere on the Property. Tenant shall,
at its sole cost,  comply with any and all Governmental  Regulations  respecting
the handling,  use, storage and disposal of Hazardous  Materials used by Tenant.
Tenant shall,  at its sole cost,  make any and all  improvements to the Premises
necessary to assure legal and safe use of Tenant's Hazardous Materials. All such
improvements  shall  be  subject  to  Landlord's  approval  in  accordance  with
Paragraph 10 hereof.  Tenant shall remove all Hazardous Materials used by Tenant
or brought onto the  Premises or the Property by Tenant prior to the  expiration
of the Lease term or sooner termination thereof.

                D. Tenant shall  indemnify,  defend and hold  Landlord  harmless
from and against  any and all claims,  judgments,  liability,  damage,  decrees,
liens, demands,  taxes,  penalties,  fines,  expenses,  costs (including but not
limited to those costs  associated  with  investigation,  removal  and  remedial
activities as may be sought, initiated or required in connection with any local,
state or  federal  governmental  or  private  party  demands  or  claims),  fees
(including without limitation attorneys fees), obligations,  orders, liabilities
or  losses  (including  without  limitation,  diminution  in  the  value  of the
Property,  damages for the loss or restriction on the use,  marketability or any
other amenity of the Property)  (all of the foregoing  collectively  referred to
hereinafter as  "Environmental  Claims"),  which arise during or after the Lease
term as a result of Tenant's use, storage,  disposal,  transportation,  release,
discharge or  generation  of any  Hazardous  Materials at, in, onto or under the
Property,  or any contamination of the Property caused by Tenant.  The foregoing
indemnity ("Tenant's  Environmental  Indemnity") shall survive the expiration or
earlier  termination  of this Lease.  Tenant agrees to defend all  Environmental
Claims on behalf of Landlord with counsel reasonably acceptable to Landlord.

                E.  Without  limiting  the  foregoing,  if there is a release or
discharge  of any  Hazardous  Materials  at, in,  onto or under the  Property or
contamination  of  the  Property  that  is  covered  by  Tenant's  Environmental
Indemnity,  Tenant  shall  promptly  take all  action,  at its sole cost,  as is
necessary to return the  Property to the  condition  required by all  applicable
laws and regulations,  provided that Landlord's  written approval of such action
shall first be obtained and Landlord's  approval of any  remediation  plan shall
not be unreasonably withheld.

                F.  Landlord  shall  have the  right to enter the  Premises  and
Property  and  perform  such  environmental   investigations,   remediation  and
assessments of the Premises as Landlord shall in Landlord's sole discretion deem
advisable.  Landlord  shall provide  Tenant with at least two (2) business days'
notice  prior  to  entering  the  Premises  hereunder,  except  in the  case  of
emergency.  Landlord shall use reasonable efforts to minimize  interference with


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Tenant's business,  but shall not be liable for any interference caused thereby.
The  cost  of  any  such  investigation,  remediation  or  assessment  shall  be
reimbursed  by Tenant to Landlord  within thirty (30) days of receipt of written
invoices therefor only if any contamination found has been caused by Tenant.

                  G.  If at  anytime  Tenant  shall  become  aware  of  or  have
reasonable cause to believe that any Hazardous Materials have come to be located
on  or  beneath  the  Premises  or  Property.  Tenant  shall,  immediately  upon
discovering  such presence or suspected  presence of Hazardous  Materials,  give
written  notice  of such  condition  to  Landlord.  In  addition,  Tenant  shall
immediately  notify  Landlord  in  writing  if Tenant  becomes  aware of (1) any
enforcement,   cleanup,   removal  or  other   governmental   regulatory  action
instituted,  completed,  or threatened relating to any Hazardous Materials on or
about the  Property,  (2) any claim made or  threatened  by any  person  against
Tenant,  Landlord  or  the  Property  relating  to  damage,  contribution,  cost
recovery,  compensation,  loss or injury relating from or claimed to result from
any Hazardous  Materials  that have come to be located on or about the Property,
and (3) any reports  made to any local,  state or federal  environmental  agency
arising out of or in  connection  with any  Hazardous  Materials on or about the
Property,   including  any  complaints,   notices,  warnings  or  violations  in
connection therewith.

                H. Any  default  under this  Paragraph  2.4 shall  constitute  a
material default enabling  Landlord to exercise any of the remedies set forth in
this Lease.

3.       TERM

         3.1 Commencement  Date. The Commencement Date of the term of this Lease
shall be as set forth in the Lease Summary.  If the  Commencement  Date is other
than the first day of a calendar month,  the Lease term shall be extended by the
number of days remaining in the month during which the Commencement Date occurs,
and Base Rent for such period shall be a prorated  portion of the same Base Rent
set forth in the Lease Summary for the first calendar month of the Lease term.

         3.2  Proration.  In the event that the Lease term  commences  on a date
other than the first day of a calendar  month,  Tenant  shall pay to Landlord on
the Commencement  Date as rent for the period from the Commencement  Date to the
first day of the next  succeeding  calendar  month that  proportion  of the rent
payable hereunder which the number of days between the Commencement Date and the
first day of the next  succeeding  calendar  month bears to thirty (30).  In the
event that the Lease term for any reason  ends on a date other than the last day
of a calendar  month,  on the first day of the last calendar  month of the Lease
term,  Tenant shall pay to Landlord as rent for the period from the first day of
said last  calendar  month to and including the last day of the term hereof that
proportion of the rent then due  hereunder  which the number of days between the
first day of said last calendar  month and the last day of the term hereof bears
to thirty (30).

4.       RENT

        4.1 Base Rent.  Tenant shall pay monthly base rent ("Base  Rent") in the
amounts set forth on the Lease Summary to Landlord  without  deduction,  offset,
prior notice,  or demand,  in advance on the first day of each calendar month of
the Lease  term and in lawful  money of the  United  States.  Base Rent shall be
abated for months 1 through 24  provided  Tenant is not in default of any of its
obligations under this Lease.


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        4.2 Additional Rent.

           A.  Tenant  shall pay to Landlord in addition to Base Rent during the
Lease  term  additional  rent  ("Additional  Rent")  equal  to  the  sum  of the
following:

              1.  Tenant's  Share of all Real  Property  Taxes  relating  to the
Property as set forth in Paragraph 11, unless Tenant shall pay the Real Property
taxes directly to the charging authority;

              2.  Tenant's  Share  of all  Operating  Expenses  relating  to the
Buildings  and the  Property as set forth in  Paragraph  7, except to the extent
Tenant maintains and repairs the Buildings as provided herein;

              3. All other charges,  costs and expenses which Tenant is required
to pay hereunder and all damages, costs and expenses which Landlord may incur by
reason of default of Tenant or failure on Tenant's part to comply with the terms
of this Lease, including attorney's fees and court costs; and

           B. In the event of nonpayment by Tenant of Additional Rent,  Landlord
shall have all the rights and remedies with respect  thereto as Landlord has for
nonpayment  of Base Rent.  Tenant's  Share of all expenses to be paid by it with
respect to the  Buildings  and  Tenant's  Share of all expenses to be paid by it
with  respect to the  Property are  separately  set forth in the Lease  Summary.
Except  as  provided  below,  Additional  Rent  due  hereunder  shall be paid to
Landlord  within thirty (30) days of written  notice by Landlord.  At Landlord's
option,  Tenant shall pay to Landlord monthly,  in advance,  on the first day of
each  calendar  month  Tenant's  Share of an amount  estimated by Landlord to be
Landlord's   approximately  monthly  expenditure  for  such  items  included  in
Additional Rent (the "Estimated Monthly  Expense").  Actual expenses incurred by
Landlord shall be reconciled  against the Estimated Monthly Expense by Landlord,
at its  option,  or at the end of each  calendar  quarter  or year.  Within  one
hundred twenty (120) days  following each calendar  quarter or year, as the case
may be,  Landlord  shall  furnish  Tenant a  statement  of the  actual  expenses
incurred  by  Landlord  for such  period.  If  Tenant's  total  payments  of the
Estimated  Monthly  Expense  for such  period are less than the amount of actual
expenses  incurred by Landlord,  Tenant shall pay to Landlord the amount of such
deficiency within thirty (30) days after receipt of such statement.  If Tenant's
total payments of the Estimated  Monthly Expense exceed actual expenses incurred
by Landlord for such period,  Landlord shall apply the excess amount against the
next  payment of Base Rent or  Additional  Rent due  hereunder or any other sums
then due under this Lease, at Landlord's sole discretion.  The Estimated Monthly
Expense may be adjusted by  Landlord  upon thirty (30) days'  written  notice to
Tenant.  The respective  obligations of Landlord and Tenant under this paragraph
shall survive the  expiration or earlier  termination of the term of this Lease,
and if the term hereof shall expire or shall otherwise  terminate on a day other
than the last day of a calendar  year, the actual  Additional  Rent incurred for


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the calendar year in which the Lease term expires or otherwise  terminates shall
be  determined  and settled on the basis of the  statement of actual  Additional
Rent for such  calendar year and shall be prorated in the  proportion  which the
number of days in such calendar year  preceding  such  expiration or termination
bears to 365.

           C.  Audit.  Tenant  shall have the  right,  at such time and place as
Landlord may reasonably  designate,  to inspect and audit  Landlord's  books and
records related to the operation and maintenance of the Building for the purpose
of verifying  Landlord's  adjusted  year-end  statement  of  Operating  Expenses
payable by Tenant.  Tenant may employ an independent  public  accounting firm to
conduct  the audit.  The costs of the audit  shall be paid by Tenant  unless the
audit shows that Landlord's adjusted statement  over-charged Tenant its share of
Operating costs by more than ten percent (10%), in which case Landlord shall pay
all Tenant's costs of the audit.

        4.3 Late  Charge and  Interest.  Tenant  hereby  acknowledges  that late
payment by Tenant to  Landlord of Base Rent,  Additional  Rent or other sums due
hereunder  (collectively,  "Rent")  will  cause  Landlord  to  incur  costs  not
contemplated  by this  Lease,  the  exact  amount  of  which  will be  extremely
difficult to ascertain.  Such costs include,  but are not limited to, processing
and accounting charges, and late charges which may be imposed on Landlord by the
terms of any  mortgage  or deed of trust  covering  the  Building  or  Property.
Accordingly, if any installment of Rent due from Tenant shall not be received by
Landlord  within (10) days after such amount shall be due, then Tenant shall pay
to Landlord a late charge equal to five percent (5%) of such overdue amount. The
parties  hereby  agree that such late charge  represents  a fair and  reasonable
estimate of the costs  Landlord  will incur by reason of late payment by Tenant.
Acceptance of such late charge by Landlord shall in no event constitute a waiver
of Tenant's  default with respect to such overdue amount,  nor prevent  Landlord
from exercising any of the other rights and remedies granted  hereunder.  In the
event any Rent due hereunder remains delinquent for a period in excess of thirty
(30) days,  Tenant  shall pay to  Landlord,  in  addition  to the late  payment,
interest from and after said date at the rate of twelve  percent (12%) per annum
(the  "Interest  Rate") until paid in full.  Payment of such interest  shall not
excuse or cure any default by Tenant.

        4.4 Place of Payment.  All payments of Rent shall be paid to Landlord at
its  office as shown on the Lease  Summary  or to such  other  person or to such
other place as Landlord may from time to time designate in writing.

        4.5  Security  Deposit.  Tenant shall not be required to post a security
deposit.

5. PARKING.  Tenant shall have the right to use all available parking spaces for
the Property in accordance with the local zoning rules.

6.  MAINTENANCE  AND  REPAIRS 

        6.1 General.  Except as otherwise  specifically  provided herein, Tenant
shall, at Tenant's sole cost, keep in good and safe condition, order and repair,
and  replace  when  necessary,  all  non-structural  portions  of the  Building,
including  all areas of the Building and exterior  portions  thereof and outside
areas,   including  without  limitation,   (1)  all  plumbing,   automatic  fire
extinguishing  and  sewage  systems,  including  water and drain  lines,  sinks,
toilets,  faucets,  drains,  showers and water  fountains,  (2) all parts of the
heating,  ventilation and air  conditioning  system ("HVAC System")  serving the
Buildings,  including all ducts, pipes, vents,  compressors,  Building fans, air
handlers,  thermostats,  time clocks,  boilers,  heaters,  and supply and return
grills serving the Building,  (3) all electrical  and lighting  facilities,  and
other  operating  systems,  appliances,  and  equipment  serving  the  Building,
including all wiring, panels, conduit, outlets, lighting fixtures, lamps, bulbs,
tubes  and  ballasts,  (4) the  elevator  and all  components  thereof,  (5) all
fixtures, interior walls, interior and exterior surfaces of exterior walls, wall


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coverings,  window coverings,  carpets,  floors, floor coverings,  partitioning,
ceilings  and  ceiling  tiles,  (6)  all  windows  (including  glazing),  doors,
entrances,  truck  doors,  glass,  plate  glass  and  skylights  located  in the
Building, and (7) all landscaping and parking areas, including routine cleaning,
maintenance, patching, resealing, repairing and restripping.

        Tenant shall  maintain the HVAC system in accordance  with EPA and State
of Washington  DOE mandated  requirements.  Tenant shall have the benefit of all
warranties available to Landlord regarding the equipment in the HVAC System, the
roof  membrane and other  equipment or items in the Building  which are Tenant's
obligation  to  maintain.  All  repairs and  maintenance  required to be made by
Tenant  hereunder  shall be made  promptly  by a  licensed  contractor  with new
materials   of  like  kind  and   quality.   If  the  repair  work  affects  the
non-structural  parts  of the  Building  and the  estimated  cost of any item of
repair  exceeds  $25,000,  then Tenant  shall first  obtain  Landlord's  written
approval  of the scope of work,  plans  therefor,  materials  to be used and the
contractor.  Landlord's  approval  thereof shall not be  unreasonably  withheld.
Tenant  hereby  waives the benefit of any statute now or  hereinafter  in effect
which would  otherwise  afford  Tenant the right to make  repairs at  Landlord's
expense or to terminate  this Lease  because of  Landlord's  failure to keep the
Premises in good condition, order and repair. Upon expiration of the Lease Term,
Tenant  shall  deliver  the HVAC System in good  working  order,  condition  and
repair.

        6.2 Certain Capital  Expenditures  by Landord.  Landlord shall maintain,
repair and  replace  if, and when  necessary,  all  structural  portions  of the
Building,  including the roof  structure,  roof  membrane,  foundation and floor
slabs;  and shall be  responsible  for repaving the parking  areas,  if and when
necessary,  with the costs of any such  structural  repairs and  replacements or
repaving  to be divided  over 120 months and Tenant will  reimburse  Landlord by
making  supplemental  monthly payments equal to 1/120th of such costs each month
for the remaining duration of the Lease and; such monthly supplemental  payments
to be  considered  additional  Operating  Expenses  for  which  Tenant  shall be
responsible in accordance with Section 4.2.

7.       OPERATING EXPENSES

        7.1 Tenant's Obligation to Reimburse. Tenant shall pay Tenant's Share of
all Operating  Expenses (as  hereinafter  defined) as may be paid or incurred by
Landlord  during the term of this Lease as Additional  Rent in  accordance  with
Paragraph 4.2 hereof.  The term  "Operating  Expenses" shall mean the sum of the
following:

           A. All costs or expenses  paid or incurred  by  Landlord,  if any, in
maintaining,  operating and repairing the Buildings,  excluding only those items
required to be maintained by Tenant at its sole cost, pursuant to Paragraph 6.


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           B. The cost of  insurance  carried by  Landlord  in  accordance  with
Paragraphs  12.4 and 12.5 hereof and fairly  allocable to the Building,  and any
insurance deductible payable under such policies.

           C. The cost of all utilities furnished to the Premises if not paid by
Tenant directly.

           D. The additional monthly amounts, if any, payable by Tenant pursuant
to Paragraph 6.2 above.

        7.2 Tenant's Negligence.  Notwithstanding  anything in Paragraphs 7.1 to
the  contrary,  and  subject  to the waiver of  subrogation  rights set forth in
Paragraph  12.7,  Tenant shall pay for the entire  uninsured cost of maintaining
and repairing  the  Buildings  and the exterior  areas thereof and any insurance
deductible if such cost or deductible is incurred as a result of the  negligence
or willful misconduct of Tenant, its agents, customers,  employees,  contractors
or invitees.

8. ACCEPTANCE AND SURRENDER OF PREMISES.  Except as otherwise expressly provided
herein,  by entry  hereunder,  Tenant  accepts the Premises as being in good and
sanitary order,  condition and repair and accepts the Buildings and improvements
included in the Premises in their present  condition and without  representation
or warranty by Landlord as to the condition of the Buildings or as to the use or
occupancy which may be made thereof.  Except as otherwise expressly provided for
herein,  Landlord shall not be responsible  for any tenant  improvements  to the
Premises of any kind or nature whatsoever.  Tenant agrees on the last day of the
Lease  term,  or on the sooner  termination  of this  Lease,  to  surrender  the
Premises  promptly to Landlord in good condition and repair  (damages by acts of
God, fire, normal wear and tear excepted),  with all interior walls painted,  or
cleaned  so that  they  appear  freshly  painted,  and all  holes  in the  walls
repaired,  patched and  repainted,  all floors  cleaned  and waxed,  all carpets
cleaned and  shampooed  and  replaced to the extent of  excessive  wear  through
failure to use carpet shields,  all broken,  damaged,  stained or  nonconforming
ceiling  tiles  replaced.  The HVAC  System and roof  membrane  shall be in good
condition and repair. Landlord shall have the right, at its expense, to retain a
qualified and licensed roof and HVAC contractor to perform an inspection thereof
and do an inventory of all components  thereof which need repair or replacement.
Tenant shall perform all such repair and  replacement  reasonably  designated by
such contractor.  All plumbing,  electrical and lighting systems,  both interior
and  exterior  shall be in good repair and  condition.  Tenant  shall remove all
monument and other signs and repair any damage caused thereby.  The term "normal
wear and  tear"  shall be deemed  to  exclude  items of  neglected  or  deferred
maintenance.  All alterations,  additions,  and improvements which may have been
made in,  to,  or on the  Premises  by Tenant  (except  movable  trade  fixtures
installed at the expense of Tenant) shall be  surrendered  in good condition and
repair, except that Tenant shall ascertain from Landlord within thirty (30) days
before the end of the Lease term whether  Landlord  desires to have the Premises
or any part or parts  thereof  restored  to their  condition  and  configuration
existing when the Premises were  delivered to Tenant,  and if Landlord  shall so
desire, then Tenant shall restore said Premises or such part or parts thereof to
their condition  existing before the Lease term, at Tenant's sole cost,  except,
however,  that  Tenant's  obligation  to restore if elected by Landlord does not
include the removal of the Tenant  Improvements  outlined in Paragraph 40. On or


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before the end of the Lease term or sooner  termination  of this  Lease,  Tenant
shall  remove all of Tenant's  personal  property  and trade  fixtures  from the
Premises,  and all property not so removed  shall be deemed  abandoned by Tenant
and title to same shall  thereupon  pass to  Landlord  without  compensation  to
Tenant.  Upon  termination  of this  Lease,  Landlord  may remove  all  moveable
furniture  and  equipment  so abandoned by Tenant,  at Tenant's  sole cost,  and
repair any damage caused by such removal.

9.       ALTERATIONS.

        9.1  Landlord's   Consent.   Tenant  shall  not  make  any  alterations,
improvements,   additions,   or   utility   installations   (collectively,   the
"Alterations")  in, on or about the Premises  without  Landlord's  prior written
consent, which shall not be unreasonably withheld, except for any non-structural
alterations  to the  interior of the  Premises  which do not exceed  twenty-five
thousand  dollars  ($25,000)  in cost  per  project.  As used  herein,  the term
"utility  installation" means power panels, wiring,  florescent fixtures,  space
heaters, conduits, air conditioning and plumbing.

        9.2 Plans and Permits.  Any alteration that Tenant desires to make in or
about the Premises and which requires the consent of Landlord shall be presented
to Landlord in written form for  Landlord's  approval,  with  proposed  detailed
plans and  specifications  therefor,  including  an  original  sepia at 1/8 inch
scale,  prepared at Tenant's sole cost. Any consent by Landlord thereto shall be
deemed  conditioned  upon Tenant's  acquisition of all permits  required to make
such Alterations from all appropriate  governmental  agencies, the furnishing of
copies thereof to Landlord prior to commencement of the work, and the compliance
by Tenant  with all  conditions  of said  permits  in a prompt  and  expeditious
manner, all at Tenant's sole cost. Landlord shall be deemed to have consented to
any alteration,  improvement  addition or utility installation if Landlord fails
to respond  within ten (10) business  days of receipt of the plans,  permits and
documents  referenced  herein and written request for Landlord's  consent.  Upon
completion  of any such  Alterations,  Tenant  shall,  at  Tenant's  sole  cost,
immediately deliver to Landlord "as-built" plans and specifications therefor. No
later than January 10th each year during the Lease term, Tenant shall deliver to
Landlord bluelines and mylar plan updates showing the configuration of the floor
plan in the Building.

        9.3 Construction  Work Done by Tenant.  Except as hereinafter  provided,
all  construction  work  required  or  permitted  to be done by Tenant  shall be
performed  by a  licensed  contractor  approved  by  Landlord  and in a  prompt,
diligent,  and good and  workmanlike  manner.  In lieu of the foregoing,  Tenant
shall have the right to use its own work crews. All such construction work shall
conform in quality and design with the Premises  existing as of the Commencement
Date and shall not diminish the value of the Buildings or the Property. All such
construction   work  shall  be  performed  in  compliance  with  all  applicable
Governmental Regulations.

        9.4 Roof Repairs.  Any  installation of air  conditioning  equipment and
duct  work  or  antennas  on  the  roof  permitted  by  Landlord  and  requiring
penetration  of the roof shall be properly  flashed and caulked.  Any  equipment
placed by Tenant on the roof shall be elevated and supported by Tenant so as not
to create vibration or inhibit drainage or repair and maintenance of the roof.

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        9.5 Title to Alterations.  Unless Landlord  requires the removal thereof
as set  forth in this  Paragraph  9, any  Alterations  which  may be made on the
Premises by Tenant shall,  upon expiration or termination of this Lease,  become
the  property of Landlord  and shall  remain  upon and be  surrendered  with the
Premises at the expiration or sooner termination of this Lease. Without limiting
the generality of the foregoing,  all heating,  lighting,  electrical (including
all  wiring,  conduits,  main  and  subpanels),   air  conditioning,   plumbing,
partitioning (except movable partitions), drapery, and carpet installations made
by Tenant,  regardless of how affixed to the  Premises,  together with all other
alterations  that have become an  integral  part of the  Premises,  shall be and
become the property of Landlord upon expiration or termination of this Lease and
shall not be deemed trade  fixtures,  and shall  remain upon and be  surrendered
with the  Premises  at the  expiration  or  sooner  termination  of this  Lease.
Tenant's furnishings,  machinery and equipment,  except that which is affixed to
the  Premises  so that it  cannot  be  removed  without  material  damage to the
Premises,  shall remain the property of Tenant and may be removed by Tenant, and
Tenant shall, at Tenant's sole cost, immediately after removal repair any damage
to the  Premises  caused  thereby.  Tenant shall be solely  responsible  for the
maintenance  and  repair  of any  and all  Alterations  made  by  Tenant  to the
Premises.

        9.6  Notice.   Tenant  shall  give  Landlord   notice  of  the  date  of
commencement  of any work in the  Premises  not less  than ten (10)  days  prior
thereto, and Landlord shall have the right to post notices of non-responsibility
or similar notices in or on the Premises in connection therewith.

10.  UTILITIES  AND  SERVICES.  Tenant  shall pay all  charges  for water,  gas,
electricity,  telephone,  refuse  pickup,  janitorial  services,  and all  other
utilities  and services  supplied or furnished to the Buildings and the Property
during the term of this Lease, together with any taxes thereon,  directly to the
charging  authority.  In no event  shall  Landlord  be liable to Tenant  for any
failure or  interruption  in utility or  service  unless  caused by the  willful
misconduct  of Landlord.  No failure or  interruption  of any such  utilities or
services  shall  entitle  Tenant to terminate  this Lease or to withhold rent or
other  sums due  hereunder.  Landlord  shall not be  responsible  for  providing
security guards or other security  protection for any portion of the Premises or
the  Property,  and  Tenant  shall at its own  expense  provide  or obtain  such
security  services as Tenant  shall  desire to ensure the safety of the Premises
and the Property.

11.      TAXES.

        11.1 Real  Property  Taxes.  Tenant  shall pay  directly to the charging
authority  Tenant's  Share of all Real Property Taxes (as  hereinafter  defined)
which  become due during the Lease  term.  If  Landlord is required to make such
payments  because  Tenant fails to do so, such  payments  shall be reimbursed by
Tenant to Landlord  promptly on demand,  as Additional  Rent in accordance  with
Paragraph 4.2 hereof.  The term "Real Property  Taxes" as used herein shall mean
(1) all  taxes,  assessments,  levies,  and other  charges of any kind or nature
whatsoever,   general  and  special,  foreseen  and  unforeseen  (including  all
installments  of principal  and interest  required to pay any general or special
assessments   for  public   improvements   and  any  increases   resulting  from
reassessments  caused  by  any  change  in  ownership  of the  Property)  now or
hereafter imposed by any governmental or quasi-governmental authority or special


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or community  facilities  district having the direct or indirect power to tax or
levy assessments,  which are levied or assessed against,  or with respect to (a)
the value,  occupancy,  ownership  or use of, all or any portion of the Property
(as now constructed or as may at any time hereafter be constructed,  altered, or
otherwise changed) or Landlord's interest therein;  (b) any improvements located
on the Property (regardless of ownership); (c) the fixtures, equipment and other
property  of  Landlord,  real or  personal,  that  are an  integral  part of the
Property;  (d) the gross receipts,  income and rentals from the Property, or (e)
the use of public utilities or energy in the Buildings;  (2) all charges, levies
or fees in the nature of a tax or assessment  imposed by reason of environmental
regulation  or  other  governmental   control  of  the  Property;   (3)  excise,
transaction,  sales,  privilege  or other taxes now or  hereafter  imposed  upon
Landlord  as a result  of this  Lease;  and (4) all  costs  and fees  (including
attorneys'  fees) incurred by Landlord in contesting any Real Property Taxes and
in negotiating  with public  authorities as to any Real Property Taxes, but only
to the extent of savings realized by Tenant as a result thereof.  If at any time
during the Lease term the taxation or assessment  of the Property  prevailing as
of the  Commencement  Date shall be altered so that in lieu of or in addition to
any Real  Property  Taxes  described  above there  shall be levied,  assessed or
imposed  (whether by reason of a change in the method of taxation or assessment,
creation of a new tax or charge, or any other cause) an alternate, substitute or
additional  tax or charge (a) on the value,  use or occupancy of the Property or
Landlord's interest therein; (b) on or measured by the gross receipts, income or
rentals from the Property;  (c) on Landlord's  business of leasing the Property;
or (d)  computed in any manner with respect to the  operation  of the  Property,
then any such tax or charge,  however  designated,  shall be included within the
meaning of the term "Real Property Taxes".  Notwithstanding  the foregoing,  the
term "Real  Property  Taxes"  shall not  include  estate,  inheritance,  gift or
franchise  taxes of  Landlord  or the federal or state net income tax imposed on
Landlord's income from all sources.

        11.2 Taxes on Tenant's Property.

           A. Tenant shall pay at least ten (10) days prior to  delinquency  all
taxes, license fees and public charges assessed or levied against all equipment,
personal  property or trade fixtures  placed by Tenant in or about the Premises.
If any such taxes,  fees or charges are levied against  Landlord or the Property
or if the assessed  value of the Premises is increased by the inclusion  therein
of the value placed upon such equipment,  personal property or trade fixtures of
Tenant and if Landlord pays the taxes,  fees or charges based on such  increased
assessment, which Landlord shall have the right to do regardless of the validity
thereof,  Tenant shall upon demand, repay to Landlord the taxes, fees or charges
so levied  against  Landlord,  or the portion of such taxes  resulting from such
increase in the assessment.

           B. If  Tenant's  improvements  in the  Premises,  whether  installed,
and/or  paid for by  Landlord  or Tenant and  whether or not affixed to the real
property so as to become a part  thereof,  are  assessed  for real  property tax
purposes  at a valuation  higher than the  valuation  at which  standard  office
improvements in other space in the Property are assessed, then the real property
taxes and assessments  levied against Landlord or the Property by reason of such
excess assessed  valuation  shall be deemed to be taxes levied against  personal
property of Tenant and shall be governed by the  provisions of Paragraph  11.2A.
If the records of the County Assessor are available and sufficiently detailed to
serve as a basis for determining whether said Tenant's improvements are assessed
at a higher  valuation than standard  office  improvements in other space on the
Property,  such records  shall be binding on both  Landlord  and Tenant.  If the
records of the County  Assessor are not  available or  sufficiently  detailed to
serve as a basis for making such determination,  the actual cost of construction
shall be used.


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12.      INSURANCE.

        12.1 Tenant's Liability Insurance.  Tenant shall, at Tenant's sole cost,
keep in force  during the Lease term a policy of  commercial  general  liability
insurance  covering  property damage and liability for personal injury occurring
in, on or about the Premises, the Buildings and the Property, with limits in the
amount of at least $2,000,000 per occurrence for injuries to or death of persons
and  $1,000,000  per  occurrence  for property  damage,  and with a  contractual
liability  endorsement  insuring Tenant's  performance of Tenant's obligation to
indemnify Landlord contained in Paragraph 13.

        12.2 Tenant's Casualty  Insurance.  Tenant shall, at Tenant's sole cost,
maintain  during the Lease term a policy or policies of fire and property damage
insurance in "all risk" form,  with a sprinkler  leakage and flood  endorsement,
insuring the personal property, inventory; and trade fixtures, within the leased
Premises for the full  replacement  cost thereof.  The proceeds form any of such
policies shall be used for the repair or replacement of such items so insured.

         12.3 Form and  Certificates.  Each policy of  insurance  required to be
carried by Tenant  pursuant to Paragraphs  12.1 and 12.2 shall be with a company
approved by Landlord and shall name  Landlord and such other parties in interest
as Landlord  reasonably  designates as additional  insured.  Tenant's  insurance
policy shall also be primary  insurance,  without right of contribution from any
policy carried by Landlord, and shall contain a cross-liability and severability
endorsement.  A certificate of insurance  shall be provided to Landlord prior to
the Commencement Date which indicates that the coverage required hereunder is in
effect and which  provides  that such  policy is not  subject  to  cancellation,
expiration  or change,  except upon thirty  (30) days' prior  written  notice to
Landlord.

        12.4 Landlord's Liability Insurance. Landlord shall maintain a policy or
policies of commercial  general liability  insurance insuring Landlord (and such
other entities as may be designated by Landlord)  against liability for personal
injury,  bodily  injury or death and damage to property  occurring  or resulting
from an occurrence  in, on, or about the Property with such coverage as Landlord
may from time to time determine is reasonably necessary for its protection.

        12.5 Property Insurance.  Landlord shall obtain and keep in force during
the term of this Lease a policy or  policies  of  insurance  for the  benefit of
Landlord covering loss or damage to the Buildings,  and the Property  (excluding
coverage of  merchandise,  fixtures,  equipment  and leasehold  improvements  of
Tenant)  in  the  amount  of  the  full  replacement  value  thereof,  providing
protection  against  all  perils  included  within the  classification  of fire,
extended coverage,  vandalism,  malicious mischief, special extended perils (all
risk),  including  earthquake,  flood,  sprinkler leakage,  boiler and machinery
coverage and an inflation  endorsement.  In addition,  Landlord shall obtain and
keep in force,  during the term of this Lease, a policy of rental loss insurance
covering a period of one year,  commencing  on the date of loss,  with  proceeds
payable to Landlord,  which  insurance shall also cover all Real Property Taxes,
Operating Expenses,  and other sums payable by Tenant hereunder for said period.


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All proceeds under such policies of insurance shall be payable to Landlord,  and
Tenant  shall have no interest  in or right to such  proceeds.  Tenant  shall be
responsible  for paying  any  deductible  under the  property  insurance  policy
carried by Landlord  hereunder,  not to exceed Fifty Thousand Dollars  ($50,000)
per occurrence.

        12.6  Payment.  Tenant  shall pay to  Landlord  during  the term  hereof
Tenant's  Share of the premiums and  deductibles  for any insurance  obtained by
Landlord pursuant to Paragraphs 12.4 and 12.5; provided,  however, that Tenant's
responsibility  to pay  Landord for the  premium  cost of rental loss  insurance
shall not  exceed  $500 per year and the  deductible  cost  shall not exceed Ten
Thousand  Dollars  ($10,000)  per  occurrence.  Landlord  may  obtain  liability
insurance  for the Building  separately,  or together  with other  buildings and
improvements  under blanket policies of insurance.  In such case Tenant shall be
liable for only such portion of the  premiums  for such blanket  policies as are
allocable to the Premises, as reasonably determined by the insurer or Landlord.

        12.7 Waiver of  Subrogation.  Tenant and Landlord each hereby waives any
and all  rights of  recovery  against  the  other,  and  against  the  officers,
employees, agents and representatives of the other, for loss of or damage to the
property of the waiving  party or the property of others  under its control,  to
the  extent  such loss or damage  is  covered  by  proceeds  received  under any
insurance  policy carried by Landlord or Tenant and in force at the time of such
loss or damage.  Tenant and  Landlord  shall,  upon  obtaining  the  policies of
insurance required  hereunder,  give notice to the insurance carrier or carriers
that the foregoing mutual waiver of subrogation is contained in this Lease.

        12.8 No Limitation of Liability.  Landlord makes no representation  that
the limits of liability  insurance specified to be carried by Tenant or Landlord
under the terms of this  Lease are  adequate  to protect  any  party.  If Tenant
believes that the insurance  coverage  required under this Lease is insufficient
to adequately  protect Tenant,  Tenant shall provide,  at its own expense,  such
additional insurance as Tenant deems adequate.

13.  WAIVER  AND  INDEMNIFICATION.  Landlord  shall not be liable to Tenant  and
Tenant hereby waives all claims  against  Landlord for any injury to or death of
any person or damage to or destruction of property in or about the Premises, the
Buildings or the  Property or to Tenant's  business  from any cause  whatsoever,
including without limitation,  from theft, gas, fire, steam, oil, electricity or
leakage of any character from the roof, walls,  basement or other portion of the
Premises, the Buildings or the Property, from rain, or defects in or breakage of
pipes,  sprinklers,  plumbing,  HVAC or other sources,  excluding,  however, the
active gross negligence or willful misconduct of Landlord, its agents, servants,
employees,  invitees,  or contractors.  Tenant shall indemnify,  defend and hold
harmless Landlord, its agents,  lenders,  partners and officers from and against
any and all claims,  judgments,  damage,  demands,  losses,  expenses,  costs or
liability  arising in connection with injury to person or property from Tenant's
use of the  Premises,  or from the  conduct  of  Tenant's  business  or from any
activity,  work or things done,  permitted or suffered by Tenant in or about the
Premises  or the  Property  by Tenant or by any of  Tenant's  agents,  servants,
employees,  invitees or contractors,  or from any breach or default by Tenant in
the  performance of any  obligation on the part of Tenant to be performed  under
the  terms  of  this  Lease  (all  of the  foregoing  collectively  referred  to


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hereinafter  as "General  Indemnity  Claims"),  excluding,  however,  the active
negligence and willful misconduct of Landlord, its agents, servants,  employees,
invitees,  or contractors.  Tenant agrees to defend all General Indemnity Claims
on behalf of Landlord,  with counsel acceptable to Landlord.  The obligations of
Tenant  contained in this  Paragraph  shall survive the  expiration of the Lease
term, or sooner termination thereof.

14.  LIENS.  Tenant shall keep the Premises and the Property free from any liens
arising out of any work performed, materials furnished or obligation incurred by
Tenant.  In the event  that  Tenant  shall not,  within ten (10) days  following
notice of the  imposition  of any such lien,  cause the same to be  released  of
record,  Landlord shall have, in addition to all other remedies  provided herein
and by law, the right,  but no  obligation,  to cause the same to be released by
such means as Landlord shall deem proper,  including payment of the claim giving
rise to such lien. All sums paid by Landlord for such purpose,  and all expenses
incurred by it in connection  therewith,  shall be payable to Landlord by Tenant
on demand with interest at the Interest Rate.

15.  ASSIGNMENT AND SUBLETTING.

         15.1 Consent Required. Except as hereinafter provided, Tenant shall not
assign,  transfer,  encumber, grant any concession or license or hypothecate the
leasehold estate under this Lease, or any interest therein, and shall not sublet
the  Premises,  or any  part  thereof,  or any  right or  privilege  appurtenant
thereto, or suffer any other person or entity to occupy or use the Premises,  or
any  portion  thereof  without,  in each  case,  the prior  written  consent  of
Landlord.   Collectively,   all  of  the  foregoing   prohibited  actions  shall
hereinafter  be  referred  to  as a  "Transfer"  of  the  Lease.  The  following
conditions or standards shall be satisfied as a condition to Landlord's  consent
to a proposed  Transfer:  (1) The proposed  transferee shall expressly assume in
writing  (or in the  case  of a  sublessee  agree  to be  bound  by)  all of the
provisions,  covenants  and  conditions of the Lease on the part of Tenant to be
kept and performed;  (2) the proposed  transferee shall satisfy  Landlord's then
current  credit  standards and in Landlord's  reasonable  opinion shall have the
financial  strength and  stability to perform all of the  obligations  of Tenant
under this Lease as and when due;  (3) the  proposed  use of the Premises by the
proposed  transferee shall be lawful and be consistent with the permitted use of
the Premises under this Lease and shall not violate any restriction in any other
lease with tenants  occupying  other portions of the Property;  (4) Tenant shall
pay  Landlord's   actual   attorneys'  fees  incurred  in  connection  with  the
negotiation,  review and processing of all proposed Transfer  documents;  (5) at
the time of the proposed  Transfer,  Tenant  shall not be in default  under this
Lease; (6) the proposed  transferee shall not be a governmental entity and shall
not hold any exemption from the payment of ad valorem or after taxes which would
prohibit  Landlord from  collecting  from the transferee  any amounts  otherwise
payable under this Lease;  and (7) except for  Transfers to affiliated  entities
permitted by  Paragraph  15.6 hereof,  the  proposed  Transfer  shall be at fair
market rent.

         15.2  Documentation.  In  connection  with any  Transfer  which  Tenant
desires to make,  Tenant  shall  provide to Landlord the name and address of the
proposed  transferee,  and true and complete copies of all documents relating to
Tenant's prospective agreement to Transfer,  and audited financial statements of
the  proposed  transfer  for the past two (2)  years,  or such  other  financial
information as is reasonably  acceptable to Landlord.  Tenant shall also specify
in writing on an itemized basis all  consideration  to be received by Tenant for
such  Transfer  in the  form of lump sum  payments,  installments  of  rent,  or
otherwise.  For purposes of this  Paragraph 15, the term  "consideration"  shall
include,  without  limitation,  all monies or other  consideration  of any kind,

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including but not limited to, bonus money, and payments (in excess of book value
thereof)  for  Tenant's  assets,  fixtures,  inventory,   accounts,  good  will,
equipment, furniture, general intangibles, and any capital stock or other equity
ownership  of  Tenant.  Within  thirty  (30)  days  after  the  receipt  of such
documentation  and other  information,  Landlord  shall notify Tenant in writing
that Landlord  elects to terminate  this Lease as to the portion of the Premises
to be  Transferred  or if  Landlord  does not elect any such  termination,  then
Landlord shall either (1) consent in writing to the proposed  Transfer,  subject
to the terms and  conditions  hereinafter  set forth,  or (2)  notify  Tenant in
writing that Landlord refuses such consent and stating the reasons therefor.

         15.3  Additional  Terms and  Conditions.  As a condition to  Landlord's
granting  its  consent to any  Transfer,  except as to any  Permitted  Transfer,
Landlord may require that Tenant pay to Landlord, as and when received by Tenant
seventy-five  percent  (75%) of any excess of  consideration  to be  received by
Tenant in  connection  with said Transfer over and above the rental amount fixed
by this Lease and payable by Tenant to  Landlord,  provided  that  Tenant  shall
first be entitled to deduct Leasing  commissions and advertising  costs incurred
in obtaining the subtenant or assignee and any unamortized  Tenant  Improvements
paid by Tenant in connection with such Transfer. Each Transfer to which Landlord
has  consented  shall  be an  instrument  in  writing  in form  satisfactory  to
Landlord,  and shall be executed by both Tenant and the transferee,  as the case
may be.  Each  such  Transfer  agreement  shall  recite  that it is and shall be
subject and  subordinate  to the  provisions of this Lease,  that the transferee
accepts  such  Transfer and agrees to perform all of the  obligations  of Tenant
thereunder,  and that the  termination of this Lease shall,  at Landlord's  sole
election, constitute a termination of such Transfer. In the event Landlord shall
consent to a Transfer,  Tenant shall nonetheless remain primarily liable for all
obligations  and  liabilities  of Tenant  under this  Lease,  including  but not
limited  to  the  payment  of  Rent.  Each  proposed  Transfer   agreement  that
constitutes a sublease,  license or concession  shall provide that Landlord,  at
its option,  may require the sublessee,  licensee or  concessionaire  to pay all
rent due under such sublease, license or concession directly to Landlord instead
of  Tenant  to the  extent  Tenant  is in  default  of  payment  of any Rent due
hereunder.

         15.4 Partnership. If Tenant is a partnership, a transfer,  voluntary or
involuntary,  of all or any  part  of an  interest  in the  partnership,  or the
dissolution of the partnership,  shall be deemed a Transfer requiring Landlord's
prior written consent.

        15.5  Corporation.  If Tenant is a corporation  any dissolution or other
reorganization of Tenant
shall constitute a Transfer.

         15.6  Permitted  Transfers.   Tenant  shall  be  entitled  to  Transfer
("Permitted  Transfer")  this Lease to any parent or subsidiary  corporation  or
upon merger, sale of stock or consolidation without the prior written consent of
Landlord.  No  permitted  Transfer  shall  relieve  Tenant  of  any  obligations
hereunder.

         15.7  Landlord's  Remedies.  Subject to  Paragraph  15.6,  any Transfer
without  Landlord's prior written consent shall at Landlord's  election be void,
and shall  constitute a default under this Lease. The consent by Landlord to any
Transfer  shall not  constitute a waiver of the provisions of this Paragraph 15,
including the requirement of Landlord's prior written  consent,  with respect to

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any  subsequent  Transfer.  If Tenant  shall  purport to assign this  Lease,  or
sublease  all or any  portion of the  Premises,  or permit any person or persons
other than  Tenant to occupy the  Premises,  without  Landlord's  prior  written
consent, Landlord may collect rent from the person or persons then or thereafter
occupying  the Premises and apply the net amount  collected to the Rent reserved
herein, but no such collection shall be deemed a waiver of Landlord's rights and
remedies  under  this  Paragraph  15, or the  acceptance  of any such  purported
assignee,  sublessee  or  occupant,  or a  release  of Tenant  from the  further
performance by Tenant of covenants on the part of Tenant herein contained.

16.      DEFAULT BY TENANT.

        16.1  Event  of  Default.  The  occurrence  of any  one or  more  of the
following  events (an "Event of Default") shall  constitute a default and breach
of this Lease by Tenant:

           A. The  failure  by Tenant to make any  payment  of Rent or any other
payment  required  to be made by Tenant  hereunder,  as and when  due,  and such
failure  shall not have been cured  within ten (10) days  after  written  notice
thereof from Landlord;

           B. Tenant's failure to perform any other term,  covenant or condition
contained in this Lease and such failure  shall have  continued  for thirty (30)
days after  written  notice of such failure is given to Tenant;  provided  that,
where such  failure  cannot  reasonably  be cured  within  said  thirty (30) day
period, Tenant shall not be in default if Tenant commences such cure within said
thirty (30) day period and thereafter diligently continues completion thereof;

           C. Tenant's failure to continuously and  uninterruptedly  conduct its
business in the Premises for a period of more than ninety (90) consecutive days,
or  Tenant's  removal of all or  substantially  all of its  equipment  and other
possessions from the Premises,  without  providing  security  protection for the
Premises reasonably satisfactory to Landlord;

           D.  Tenant's  assignment  of  its  assets  for  the  benefit  of  its
creditors;

           E.  The  sequestration  of,  attachment  of,  or  execution  on,  any
substantial  part of the property of Tenant or on any property  essential to the
conduct of Tenant's  business on the  Premises,  and Tenant shall have failed to
obtain a return or release on such property within thirty (30) days  thereafter,
or  prior to sale  pursuant  to such  sequestration,  attachment  or  execution,
whichever is earlier;

           F.  An  entry  of any of  the  following  orders  by a  court  having
jurisdiction,  and such order shall have  continued  for a period of thirty (30)
days:  (1) an order for relief in any  proceeding  under  Title 11 of the United
States Code, or an order adjudicating Tenant to be bankrupt or insolvent; (2) an
order  appointing  a  receiver,  trustee or  assignee  of  Tenant's  property in
bankruptcy or any other proceeding;  or (3) an order directing the winding up or
liquidation of Tenant; or



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           G. The filing of a petition to commence against Tenant an involuntary
proceeding  under Title 11 of the United  States Code,  and Tenant shall fail to
cause such petition to be dismissed within thirty (30) days thereafter.

        16.2  Remedies.  Upon any  Event of  Default,  Landlord  shall  have the
following remedies, in addition to all other rights and remedies provided by law
or equity:

           A.  Landlord  shall be  entitled to keep this Lease in full force and
effect for so long as Landlord does not terminate  Tenant's  right to possession
(whether or not Tenant  shall have  abandoned  the  Premises)  and  Landlord may
enforce all of its rights and remedies under this Lease,  including the right to
recover Rent and other sums as they become due under this Lease; or

           B. Landlord may terminate the Tenant's  right to possession by giving
Tenant written notice of termination. Any termination under this paragraph shall
not release Tenant from the payment of any sum or performance  then due Landlord
or from any  claim for  damages  or Rent  previously  accrued  or then  accruing
against Tenant.

           In the event  this Lease is  terminated  pursuant  to this  Paragraph
16.2B., Landlord may recover from Tenant:

              (i) the worth at the time of award of the  unpaid  rent  which had
been earned at the time of termination; plus

              (ii) the  worth at the time of award of the  amount  by which  the
unpaid  rent which would have been earned  after  termination  until the time of
award  exceeds  the amount of such  rental  loss for the same period that Tenant
proves could have been reasonably avoided; plus

              (iii)  the  worth at the time of award of the  amount by which the
unpaid  rent for the  balance  of the term after the time of award  exceeds  the
amount of such  rental loss for the same  period  that  Tenant  proves  could be
reasonably avoided; plus

              (iv) any other amount necessary to compensate Landlord for all the
detriment proximately caused by Tenant's failure to perform Tenant's obligations
under this Lease,  or which in the ordinary  course of things would be likely to
result therefrom,  including but not limited to attorneys' fees, court costs and
remodeling expenses.

              The  "worth at the time of award" of the  amounts  referred  to in
subparagraphs  (i) and  (ii) of this  Paragraph  16.2B.  shall  be  computed  by
allowing  interest at the lower of five percent (5%) per annum plus the discount
rate of the Federal  Reserve  Bank of San  Francisco,  or the maximum  rate then
permitted by law. The "worth at the time of award" of the amount  referred to in
subparagraph  (iii) of this  paragraph  shall be  computed by  discounting  such
amount at the discount rate of the Federal  Reserve Bank of San Francisco at the
time of award plus one percent (1%).  The term "Rent" as used in this  paragraph
shall include all sums required to be paid by Tenant to Landlord pursuant to the
terms of this Lease.

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        C. This Lease may be terminated by a judgment specifically providing for
termination,  or by Landlord's delivery to Tenant of written notice specifically
terminating  this  Lease.  In no event  shall  any one or more of the  following
actions  by  Landlord,  in the  absence of a written  election  by  Landlord  to
terminate  this  Lease,  constitute  a  termination  of the Lease or a waiver of
Landlord's right to recover damages under this Paragraph 16:

           (i) appointment of a receiver in order to protect Landlord's interest
hereunder;

           (ii) consent to any  subletting of the Premises or assignment of this
Lease by Tenant, whether pursuant to provisions hereof concerning subletting and
assignment or otherwise; or

           (iii) any other action by Landlord or Landlord's  agents  intended to
mitigate  the adverse  effects of any breach of this Lease by Tenant,  including
without  limitation  any action taken to maintain and preserve the Premises,  or
any action taken to relet the Premises or any portion thereof for the account of
Tenant and in the name of Tenant.

        16.3 No Relief From  Forfeiture  After  Default.  To the fullest  extent
allowed by Washington law, Tenant waives all rights of redemption or relief from
forfeiture  under RCW  59.12.010 et seq.,  and under any other present or future
law,  in the event  Tenant is  evicted  or  Landlord  otherwise  lawfully  takes
possession of the Premises by reason of any Event of Default.

        16.4 Landlord's Right to Perform Tenant's  Obligations.  If Tenant shall
at any time fail to make any  payment or perform  any other act  required  to be
made or performed by Tenant under this Lease,  then  Landlord may, but shall not
be obligated to after five (5) business  days notice,  except in the case of any
emergency,  make such payment or perform  such other act to the extent  Landlord
may deem desirable,  and may, in connection therewith,  pay any and all expenses
incidental  thereto and employ  counsel.  No such  action by  Landlord  shall be
deemed a waiver by  Landlord of any rights or  remedies  Landlord  may have as a
result of such  failure by Tenant,  or a release of Tenant from  performance  of
such obligation. All sums so paid by Landlord,  including without limitation all
penalties,  interest and costs in connection therewith, shall be due and payable
by Tenant to  Landlord  on the day  immediately  following  any such  payment by
Landlord. Landlord shall have the same rights and remedies for the nonpayment of
any such sums as Landlord may be entitled to in the case of default by Tenant in
the payment of Rent.

        16.5  Additional  Rent. For purposes of any unlawful  detainer action by
Landlord  against Tenant pursuant to RCW 59.12.010,  or any similar or successor
statutes,  Landlord  shall be  entitled  to  recover  as Rent not only such sums
specified  in  Paragraph  4 as Base  Rent  and  Additional  Rent as may  then be
overdue, but also all such additional sums of Rent as may then be overdue.

        16.6 Remedies Not Exclusive.  No remedy or election  hereunder  shall be
deemed  exclusive but shall,  wherever  possible,  be cumulative  with all other
remedies herein provided or permitted at law or in equity.

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17.      DEFAULT BY LANDLORD.

        17.1 Cure Period.  Landlord  shall not be deemed to be in default in the
performance  of any obligation  required to be performed by it hereunder  unless
and until it has failed to  perform  such  obligation  within the period of time
specifically  provided herein,  or if no period of time has been provided,  then
within  thirty (30) days after  receipt of written  notice by Tenant to Landlord
specifying therein the nature such obligation;  provided,  however,  that if the
nature of  Landlord's  obligation  is such that more than  thirty  (30) days are
reasonably required for its performance, then Landlord shall not be deemed to be
in default if it shall  commence  such  performance  within such thirty (30) day
period and thereafter diligently complete such obligation.

        17.2  Mortgage  Protection.  In the event of any  default on the part of
Landlord,  Tenant  will  give  notice by  registered  or  certified  mail to any
beneficiary  of a deed of trust  or  mortgagee  of a  mortgage  encumbering  the
Premises  whose address shall have been  furnished to Tenant,  and before Tenant
shall  have  any  right  to  terminate  this  Lease,  Tenant  shall  grant  such
beneficiary  or mortgagee a reasonable  period within which to cure the default,
if such action is necessary to effect a cure.

18.  SUBORDINATION  AND MORTGAGES.  In the event  Landlord's  title or leasehold
interest is now or hereafter  encumbered by a deed of trust upon the interest of
Landlord in the land and buildings in which the demised  Premises are located to
secure a loan from a lender  (hereinafter  referred to as "Lender") to Landlord,
Tenant  shall,  within ten (10)  business  days of the  request by  Landlord  or
Lender,  execute  and deliver to Landlord  an  agreement  subordinating  Tenants
rights under this Lease to the lien of such deed of trust,  in form requested by
the Lender.  Notwithstanding the foregoing, Tenant's possession under this Lease
shall not be  disturbed  if Tenant is not in default and so long as Tenant shall
pay all Rent and observe and  perform  all of the  provisions  set forth in this
Lease, and any subordination  agreement shall expressly recognize Tenant's right
to continued occupancy under this Lease in accordance with the foregoing.

19. ENTRY BY LANDLORD.  Landlord shall at all reasonable  times and upon two (2)
business days' prior notice (except in emergencies)  have the right to enter the
Premises to inspect  them,  to perform  any  services to be provided by Landlord
hereunder,  to show  the  Premises  to  prospective  purchasers,  mortgagors  or
tenants, to post notices of  nonresponsibility  and to alter,  improve or repair
the Premises  and any portion of the  Property,  all without  abatement of rent;
provided,  however,  that  Landlord  shall use  reasonable  efforts to  minimize
interference  with  Tenant's  business.  Landlord  shall have the right to erect
scaffolding  and other  structures  in or through the Premises  when  reasonably
required  for by any work to be performed  by  Landlord.  Landlord  shall at all
times  retain a key with which to unlock all of the doors to the  Premises in an
emergency,  and any entry to the Premises  obtained by Landlord  shall not under
any circumstances be construed or deemed to be a forcible or unlawful entry into
or a detainer of the Premises or an eviction, actual or constructive,  of Tenant
from the Premises or any portion thereof.

20. VACATION OR ABANDONMENT.  Tenant shall not vacate or abandon the Premises at
any time during the term of this Lease  (except that Tenant may vacate for up to
thirty  (30)  during  any  twelve  (12)  month  period so long as it pays  Rent,



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provides an on-site  security  guard during  normal  business  hours from Monday
through Friday, and otherwise performs its obligations hereunder), and if Tenant
shall  abandon,  vacate or surrender said Premises,  or be  dispossessed  by the
process of law, or otherwise, any personal property belonging to Tenant and left
on the Premises shall be deemed to be abandoned, at the option of Landlord.

21.      DAMAGE OR DESTRUCTION.

        21.1 Partial  Damage-Insured.  Subject to the  provisions  of Paragraphs
21.3 and 21.4,  if the  Buildings  are  damaged to the extent of less than fifty
percent (50%) of the then  replacement cost thereof  (excluding  excavations and
foundations)  or the  Laboratory  Building is damaged to the extent of less than
thirty-three  and one-third  percent (33 1/3%)  (collectively,  the "Replacement
Cost"),  and such  damage  was  caused by an act or  casualty  covered  under an
insurance  policy  obtained by Landlord or Tenant  pursuant to Paragraph 12.4 or
12.5, and the proceeds of such insurance  received by Landlord are sufficient to
repair the damage,  Landlord  shall at Landlord's  expense repair such damage as
soon as  reasonably  possible  and this Lease  shall  continue in full force and
effect;  provided  that if the repair will take more than one hundred and eighty
(180) days to complete from the date of damage,  as  reasonably  estimated by an
independent licensed contractor mutually agreeable to the parties (the "Approved
Contractor"),  either  party  shall  have the right to  terminate  this Lease by
delivering written notice of such election to the other party within thirty (30)
days after receiving written notice of the Approved Contractor's  estimated time
to complete such repair.  In such event,  this Lease shall  terminate  effective
ninety (90) days after delivery of such written notice.

        21.2 Partial  Damage-Uninsured.  Subject to the provisions of Paragraphs
22.3 and 22.4,  if at any time during the term hereof the  Buildings are damaged
and the proceeds  received by Landlord are not sufficient to repair such damage,
or such damage was caused by an act or casualty  not covered  under an insurance
policy  obtained  by  Landlord or Tenant  pursuant  to  Paragraph  12.4 or 12.5,
Landlord  may at  Landlord's  option  either (1) repair  such  damage as soon as
reasonably  possible  at  Landlord's  expense,  in which  event this Lease shall
continue in full force and effect,  or (2) give written notice of termination of
this Lease to Tenant within thirty (30) days after the date of the occurrence of
such damage,  with the effective date of such  termination to be the date of the
occurrence  of such  damage.  Notwithstanding  the  foregoing,  if  such  repair
hereunder will take more than one hundred and eighty (180) days to complete from
the date of damage, as reasonably  estimated by an Approved  Contractor,  either
party shall have the right to terminate this Lease by delivering  written notice
of such  election to the other  party  within  thirty (30) days after  receiving
written  notice of the Approved  Contractor's  estimated  time to complete  such
repair.  In such event,  this Lease shall terminate  effective  ninety (90) days
after delivery of such written notice.

        21.3 Total Destruction. If at any time during the term hereof either the
Premises  or  the  Buildings  are  destroyed  to the  extent  of  sixty-six  and
two-thirds  percent  (66 2/3%) or more of the then  Replacement  Cost,  from any
cause  whether or not covered by the  insurance  obtained  pursuant to Paragraph
12.4 or 12.5, this Lease shall at the option of Landlord or Tenant  terminate as
of the date of such destruction.  Landlord or Tenant shall exercise its right to
terminate  this Lease,  if at all, by delivery of notice of  termination  to the


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other party within thirty (30) days after the date that Tenant notifies Landlord
of the occurrence of such damage. In the event neither party elects to terminate
this Lease,  Landlord shall at Landlord's  expense repair such damage as soon as
reasonably  possible,  and this Lease  shall  continue in full force and effect,
subject to the provisions of Paragraph 21.5.

        21.4 Damage Near End of Term.  If the Premises are  destroyed or damaged
in whole or in  material  part  during the last year of the Lease term and if it
would take more than ninety (90) days to repair or restore the Premises,  either
Landlord or Tenant may terminate this Lease as of the date of occurrence of such
damage by giving written  notice thereof to other party of such election  within
thirty (30) days after the date of occurrence of such damage.

        21.5  Abatement  of  Rent.  Notwithstanding  anything  to  the  contrary
contained  in this Lease,  if the Premises  are  partially  damaged and Landlord
repairs or restores them pursuant to the  provisions of this  Paragraph 21, Base
Rent and  Additional  Rent payable  hereunder  for the period  commencing on the
occurrence  of  such  damage  and  ending  upon  completion  of such  repair  or
restoration shall be abated in proportion to the extent to which Tenant's use of
the Premises is impaired  during the period of repair;  provided  that,  nothing
herein shall be construed to preclude  Landlord  from being  entitled to collect
the  full  amount  of any  rental  loss  insurance  proceeds.  Except  for  such
abatement,  if any,  Tenant shall have no claim against  Landlord for any damage
suffered by reason of any such damage, destruction, repair or restoration.

        21.6 Waiver. Tenant waives the provisions of any applicable law, and any
similar or successor  statutes  relating to termination of leases when the thing
leased  is  substantially  or  entirely  destroyed,  and  agrees  that  any such
occurrence shall instead be governed by the terms of this Lease.

        21.7  Tenant's  Property.  Landlord's  obligation  to rebuild or restore
shall  not  include   restoration   of  Tenant's  trade   fixtures,   equipment,
merchandise, or any improvements, alterations or additions made by Tenant to the
Premises.

        21.8 Notice of Damage. Tenant shall notify Landlord within five (5) days
after  the  occurrence  thereof  of any  damage  to all  or any  portion  of the
Premises.  In no event shall  Landlord have any  obligation to repair or restore
the Premises  pursuant to this  Paragraph  21 until a reasonable  period of time
after  Landlord's  receipt of notice  from Tenant of the nature and scope of any
damage to the  Premises,  and a reasonable  period of time to collect  insurance
proceeds  arising from such damage (unless such damage is clearly not covered by
insurance then in effect covering the Premises).

        21.9 Replacement  Cost. The  determination in good faith by the Approved
Contractor of the estimated cost of repair of any damage,  or of the Replacement
Cost, shall be conclusive for purposes of this Paragraph 21.

22.  EMINENT  DOMAIN.  If all or any part of the Premises  shall be taken by any
public or quasi-public authority under the power of eminent domain or conveyance
in lieu thereof, this Lease shall terminate as to any portion of the Premises so
taken or conveyed on the date when title vests in the  condemnor,  and  Landlord


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shall be entitled to any and all payment,  income,  rent, award, or any interest
therein  whatsoever  which may be paid or made in connection with such taking or
conveyance, and Tenant shall have no claim against Landlord or otherwise for the
value  of any  unexpired  term  of this  Lease.  Notwithstanding  the  foregoing
paragraph,  any compensation  specifically  awarded Tenant for loss of business,
Tenant's personal property, moving cost or loss of goodwill, shall be and remain
the property of Tenant.  If (i) any action or  proceeding  is commenced for such
taking of the Premises or any part thereof, or if Landlord is advised in writing
by any entity or body having the right or power of condemnation of its intention
to condemn the  Premises or any portion  thereof,  or (ii) any of the  foregoing
events occur with respect to the taking of any other portion of the Buildings or
Property not leased hereby, and Landlord shall decide to discontinue the use and
operation of the Buildings or Property, or decide to demolish,  alter or rebuild
the Buildings or Property,  then, in any of such events  Landlord shall have the
right to  terminate  this Lease upon  thirty (30) days prior  written  notice to
Tenant.  In the event of a partial  taking or conveyance  of the Premises  under
power of eminent domain,  if the portion of the Premises taken or conveyed is so
substantial  that the  Tenant  can no longer  reasonably  conduct  its  business
therein,  Tenant shall have the right to terminate  this Lease within sixty (60)
days from the date of such taking or conveyance, upon written notice to Landlord
of its  intention to terminate  the Lease.  Upon  delivery of such notice,  this
Lease shall  terminate on the last day of the calendar  month next following the
month in which such notice is given, upon payment by Tenant of the Rent from the
date of such taking or  conveyance to the date of  termination.  If a portion of
the Premises be taken by  condemnation or conveyance in lieu thereof and neither
Landlord nor Tenant shall  terminate this Lease as provided  herein,  this Lease
shall  continue in full force and effect as to the part of the  Premises  not so
taken or  conveyed,  and the Rent herein shall be  thereafter  be reduced to the
extent by Tenant's use or occupancy of the Premises has been adversely affected.
The rights of Landlord and Tenant regarding any taking or conveyance under power
or threat of eminent  domain  shall be governed by the terms of this  paragraph,
and each party waives the provisions of Washington Law allowing  either party to
petition a court to terminate this Lease in the event of a partial taking of the
Premises.

23. SALE OR CONVEYANCE BY LANDLORD.  In the event of a sale or conveyance of the
Property  or  any  interest  therein,   by  any  owner  of  the  reversion  then
constituting Landlord, the transferor shall thereby be released from any further
liability  upon any of the terms,  covenants or conditions  (express or implied)
herein contained in favor of Tenant, and in such event, insofar as such transfer
is  concerned,  Tenant  agrees  to  look  solely  to the  responsibility  of the
successor in interest of such  transferor in and to the Property and this Lease.
This Lease  shall not be  affected  by any such sale or  conveyance,  and Tenant
agrees to attorn to the successor in interest of such transferor.

24.  ATTORNMENT TO LENDER OR THIRD PARTY.  In the event the interest of Landlord
in the land and buildings in which the leased Premises are located (whether such
interest  of  Landlord  is a fee title  interest  or a  leasehold  interest)  is
encumbered by deed of trust,  and such interest is acquired by the lender or any
third party through  judicial  foreclosure  or by exercise of a power of sale at
private  trustee's  foreclosure  sale,  Tenant  hereby  agrees  to attorn to the
purchaser at any such  foreclosure  sale and to recognize  such purchaser as the
Landlord  under this Lease.  In the event the lien of the deed of trust securing
the loan from a Lender to Landlord  is prior and  paramount  to the Lease,  this
Lease shall  nonetheless  continue in full force and effect for the remainder of
the unexpired term hereof,  at the same rental herein  reserved and upon all the
other terms, conditions and covenants herein contained.



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25.  HOLDING  OVER.  Any  holding  over by  Tenant  after  expiration  or  other
termination  of the term of this Lease  with the  written  consent  of  Landlord
delivered to Tenant shall not  constitute a renewal or extension of the Lease or
give Tenant any rights in or to the leased Premises except as expressly provided
in this Lease. Any holding over after the expiration or other termination of the
term of this Lease,  with the consent of  Landlord,  shall be  construed to be a
tenancy from month to month, on the same terms and conditions  herein  specified
insofar as applicable except that the monthly Base Rent shall be increased to an
amount equal to one hundred  twenty-five percent (125%) of the monthly Base Rent
required during the last month of the Lease term.

26. ESTOPPEL  CERTIFICATE.  Tenant shall at any time upon not less than ten (10)
business days' prior written notice to Landlord execute, acknowledge and deliver
to Landlord a statement in writing (i) certifying  that this Lease is unmodified
and in full  force and  effect  (or,  if  modified,  stating  the nature of such
modification  and certifying that this Lease,  as so modified,  is in full force
and  effect)  and the date to  which  the Rent  and  other  charges  are paid in
advance,  if any,  and  (ii)  acknowledging  that  there  are not,  to  Tenant's
knowledge, any uncured defaults on the part of Landlord hereunder, or specifying
such  defaults,  if any, are claimed.  Any such  statement  may be  conclusively
relied  upon by any  prospective  purchaser  or  encumbrancer  of the  Premises.
Tenant's  failure to deliver such statement within such time shall be conclusive
upon Tenant that this Lease is in full force and  effect,  without  modification
except as may be represented by Landlord,  that there are no uncured defaults in
Landlord's performance, and that not more than one month's rent has been paid in
advance.

27. CONSTRUCTION  CHANGES. It is understood that the description of the Premises
and the location of ductwork,  plumbing and other facilities therein are subject
to such minor  changes as  Landlord or  Landlord's  architect  determines  to be
desirable in the course of construction of the Premises, and no such changes, or
any changes in plans for any other  portions of the  Property  shall affect this
Lease or entitle  Tenant to any  reduction  of Rent  hereunder  or result in any
liability of Landlord to Tenant. Landlord does not guarantee the accuracy of any
drawings  supplied to Tenant and  verification  of the accuracy of such drawings
rests with Tenant.

28. RIGHT OF LANDLORD TO PERFORM.  All terms,  covenants and  conditions of this
Lease to be  performed  or observed by Tenant  shall be performed or observed by
Tenant at Tenant's  sole cost and expense and without any  reduction of Rent. If
Tenant shall fail to pay any sum of money, or other Rent, required to be paid by
it  hereunder  or shall fail to perform any other term or covenant  hereunder on
its part to be performed,  and such failure shall continue for five (5) business
days  after  written  notice  of  Landlord's  intent  to  perform  such  term of
condition,  Landlord, without waiving or releasing Tenant from any obligation of
Tenant  hereunder,  may, but shall not be obligated to, make any such payment or
perform any such other term or covenant on Tenant's  part to be  performed.  All


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sums so paid by Landlord and all necessary costs of such performance by Landlord
together  with  interest  thereon  at the  Interest  Rate  from the date of such
payment or  performance  by  Landlord,  shall be paid by Tenant to  Landlord  on
demand by Landlord,  and Landlord shall have the same rights and remedies in the
event of nonpayment by Tenant as in the case of failure by Tenant in the payment
of Rent hereunder.

29. ATTORNEYS' FEES. In the event that either Landlord or Tenant should bring an
action or proceeding for the possession of the Premises, including on appeal and
petition for review for the recovery of any sum due under this Lease, or because
of the breach of any  provision of this Lease,  or for any other relief  against
the other party  hereunder,  then all costs and expenses,  including  reasonable
attorneys'  fees,  incurred by the prevailing party therein shall be paid by the
other party.

30. WAIVER.  The waiver by either party of the other party's  failure to perform
or observe any term,  covenant or condition  herein contained to be performed or
observed by such waiving  party shall not be deemed to be a waiver of such term,
covenant  or  condition  with  respect  to any  subsequent  failure of the party
failing  to perform or  observe  the same or any other  such term,  covenant  or
condition therein contained, and no custom or practice which may develop between
the parties hereto during the term hereof shall be deemed a waiver of, or in any
way affect,  the right of either party to insist upon performance and observance
by the other party in strict accordance with the terms hereof.

31. NOTICES. All notices, demands,  requests,  advices or designations which may
be or are required to be given by either party to the other  hereunder  shall be
in writing. All notices, demands,  requests, advices or designations by Landlord
to Tenant shall be sufficiently  given,  made or delivered if sent by commercial
courier or by United  States  certified or  registered  mail,  postage  prepaid,
addressed to Tenant at the Premises. All notices, demands,  requests, advices or
designations  by Tenant to Landlord shall be sent by United States  certified or
registered mail, postage prepaid, addressed to Landlord at its address set forth
on the Lease  Summary.  Each  notice,  request,  demand,  advice or  designation
referred  to in this  paragraph  shall  be  deemed  received  on the date of the
personal service or delivery thereof in the manner herein provided,  as the case
may be.

32.  EXAMINATION  AND  CONDITION OF LEASE.  Submission  of this  instrument  for
examination  or signature by Tenant does not  constitute  a  reservation  of the
Premises or option for a lease,  and this instrument is not effective as a lease
or otherwise until its execution and delivery by both Landlord and Tenant.

33.  AUTHORITY.  If Tenant is a corporation  or a partnership,  each  individual
executing this Lease on behalf of said corporation or partnership represents and
warrants that he is duly  authorized to execute and deliver this Lease on behalf
of said  corporation  or  partnership  in  accordance  with the  by-laws of said
corporation the  partnership  agreement and that this Lease is binding upon said
corporation or partnership in accordance with its terms.

34. LIMITATION OF LIABILITY.  Tenant and all successors and assigns covenant and
agree  that,  in the event of any actual or alleged  failure,  breach or default
hereunder by Landlord:


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              (i) the sole and  exclusive  remedy shall be against  Landlord and
Landlord's assets;

              (ii) no partner or owner of  Landlord  shall be sued or named as a
party in any suit or action  (except as may be necessary to secure  jurisdiction
of the partnership);

              (iii) no service of process  shall be made  against any partner of
Landlord (except as may be necessary to secure jurisdiction of the partnership);

              (iv) no partner or owner of  Landlord  shall be required to answer
or otherwise plead to any service of process;

              (v) no  judgment  will be taken  against  any  partner or owner of
Landlord;

              (vi) any judgment  taken  against any partner or owner of Landlord
may be vacated and set aside at any time without hearing;

              (vii) no writ of execution  will ever be levied against the assets
of any partner or owner of Landlord;

              (viii) these  covenants and  agreements  are  enforceable  both by
Landlord and also by any partner or owner of Landlord.

              Tenant agrees that each of the foregoing  covenants and agreements
shall be applicable to any covenant or agreement either  expressly  contained in
this Lease or imposed by statute or at common law.

35.      MISCELLANEOUS AND GENERAL PROVISIONS.

        A. Tenant shall not,  without the written  consent of Landlord,  use the
name of the  Buildings for any purpose other than as the address of the business
conducted by Tenant in the Premises.

        B. This Lease shall in all  respects be  governed  by and  construed  in
accordance  with the laws of the State of  Washington.  If any provision of this
Lease shall be invalid,  unenforceable or ineffective for any reason whatsoever,
all other provisions hereof shall be and remain in full force and effect.

        C.  The  term  "Premises"  includes  the  space  leased  hereby  and any
improvements now or hereafter  installed therein or attached  thereto.  The term
"Landlord" or any pronoun used in place  thereof  includes the plural as well as
the singular and the  successors  and assigns of Landlord.  The term "Tenant" or
any pronoun  used in place  thereof  includes the plural as well as the singular
and individuals,  firms, associations,  partnerships and corporations, and their
and each of their respective heirs,  executors,  administrators,  successors and
permitted  assigns,  according to the context hereof, and the provisions of this



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Lease  shall   inure  to  the  benefit  of  and  bind  such  heirs,   executors,
administrators, successors and permitted assigns. The term "person" includes the
plural  as  well  as  the  singular  and   individuals,   firms,   associations,
partnerships and  corporations.  Words used in any gender include other genders.
If there be more than one Tenant the  obligations of Tenant  hereunder are joint
and  several.  The  paragraph  headings  of this  Lease are for  convenience  of
reference only and shall have no effect upon the construction or  interpretation
of any provision hereof.

        D.  Time is of the  essence  of this  Lease  and of each  and all of its
provisions.

        E. At the expiration or earlier  termination of this Lease, Tenant shall
execute, acknowledge and deliver to Landlord, within ten (10) days after written
demand from Landlord to Tenant, any quitclaim deed or other document required by
any reputable title company,  licensed to operate in the State of Washington, to
remove the cloud or encumbrance  created by this Lease from the real property of
which the Premises are a part.

        F. This  instrument  along  with any  exhibits  and  attachments  hereto
constitutes  the entire  Agreement  between  Landlord and Tenant relative to the
Premises and this  agreement  and the exhibits and  attachments  may be altered,
amended or revoked only by an instrument in writing  signed by both Landlord and
Tenant.  Landlord and Tenant agree hereby that all prior or contemporaneous oral
agreements  between and among  themselves  and their  agents or  representatives
relative  to the  leasing  of the  Premises  are  merged in or  revoked  by this
agreement.

        G.  Neither  Landlord nor Tenant shall record this Lease or a short form
memorandum hereof without the consent of the other.

        H. Tenant further agrees to execute any amendments  required Landlord in
order to obtain financing for the Property, so long as Tenant's rights hereunder
are not substantially affected.

        I. All Paragraphs  listed in the Lease Summary as additional  paragraphs
are added hereto and are included as a part of this Lease.

        J. Clauses,  plats and riders, if any, signed by Landlord and Tenant and
endorsed on or affixed to this Lease are a part hereof.

        K. Tenant  covenants  and agrees that no  diminution  or shutting off of
light,  air or view by any structure which may be hereafter  erected (whether or
not by  Landlord)  shall in any way  affect  his  Lease,  entitle  Tenant to any
reduction of Rent hereunder or result in any liability of Landlord to Tenant.

        L. The  voluntary  or other  surrender  of this Lease or the Premises by
Tenant or a mutual cancellation of this Lease shall not work as a merger and, at
the option of Landlord,  shall either terminate all or any existing subleases or
subtenancies  or  operate  as an  assignment  to  Landlord  of all  or any  such
subleases or subtenancies.


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<PAGE>

        M. Tenant  acknowledges  that  Landlord  may assign its interest in this
Lease to a partnership or a limited  liability  company upon  acquisition of the
Property and that Tenant shall  thereafter  look solely to such  partnership  or
limited  liability  company for  performance  of all of  Landlord's  obligations
hereunder.

36.  BROKERS.  Tenant  warrants  that it had dealings  with only the real estate
brokers or agents listed on the Lease Summary in connection with the negotiation
of this Lease and that it knows of no other real  estate  broker or agent who is
entitled to a commission in connection with this Lease.

37. SIGNS AND WINDOW COVERINGS. No sign, placard, picture,  advertisement,  name
or notice shall be inscribed,  displayed or printed or affixed on or to any part
of the outside of the Premises or any exterior windows of the Premises except in
compliance with all  Governmental  Regulations.  Upon expiration or other sooner
termination  of this Lease,  Tenant at Tenant's sole cost and expense shall both
remove  such sign and  repair  all  damage in such a manner  as to  restore  all
aspects  of  the  appearance  of the  Premises  to the  condition  prior  to the
placement of said sign.

38. ADDITIONAL PARAGRAPHS. Paragraphs 39 through 40 in the attached Addendum and
Exhibits A are added hereto and made part of this Lease.

     IN WITNESS  WHEREOF,  Landlord and Tenant have executed and delivered  this
Lease as of the day and year first above written.

LANDLORD:                                     TENANT:

EMCON,                                        COLUMBIA ANALYTICAL SERVICES, INC.
a California corporation                      a Washington corporation



By: /s/R. Michael Momboisse                  By: /s/Steven W. Vincent
    --------------------------------             -----------------------------

Its:   CFO & VP Legal                       Its:  President
     ------------------------------              -----------------------------



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<PAGE>



                                ADDENDUM TO LEASE

         The   Addendum  is  executed  by  and  between   EMCON,   a  California
corporation,  as  Landlord,  and  Columbia  Analytical  Services,  a  Washington
corporation,  as Tenant,  with respect to those certain Premises located at 1317
13th Street, Kelso, Washington 98626-2845.  This Addendum is an integral part of
the Lease to which it is attached. The provisions of this Addendum supersede the
provisions of the Lease to the extent inconsistent therewith.

39. FIRST RIGHT OF REFUSAL TO PURCHASE  PROPERTY.  If Landlord receives an offer
to purchase  the Property at any time during the term of this Lease and Landlord
desires to accept  such  offer,  then  Landlord  shall  first  offer to sell the
Property  to Tenant upon the same terms and  conditions  by  delivering  written
notice to Tenant of all of the terms and  conditions of the third party's offer;
provided,  however,  that  Tenant  shall  receive as a credit  against  any down
payment  requirement,  the then current net book value on Tenant's  books of the
costs expended by Tenant with  Landlord's  consent after the Lease  Commencement
Date for construction of additional  buildings or building  additions or for the
buildout of the second floor of the administration  building.  Such notice shall
constitute  an offer to sell the Property to Tenant on the terms and  conditions
contained in the notice.  Tenant  shall have fifteen (15) days after  receipt of
said notice in which to notify  Landlord in writing  that  Tenant  accepts  such
offer. Tenant shall accept such offer, if at all, only by executing the purchase
agreement  attached  with  Landlord's  notice and returning the same to Landlord
within  the  fifteen  (15) day  period.  If Tenant  so  executes  said  purchase
agreement and timely  returns the same to Landlord,  Landlord  shall execute the
purchase  agreement and return a fully executed copy to Tenant.  If Tenant fails
to execute the purchase  agreement or to return the same to Landlord within said
fifteen (15) day period, then Landlord shall be entitled to sell the Property to
any other party on such terms as Landlord  desires;  provided that, the purchase
price for any purchase agreement entered into with any such third party shall be
no less than that previously offered to Tenant,  unless Landlord has first again
offered the Property to Tenant for sale on the terms  provided in this Paragraph
39. The right of first  refusal  under this  paragraph  is granted for  Tenant's
personal  benefit and may not be assigned or  transferred  by Tenant,  except in
connection with a Permitted Transfer.  Likewise, if Tenant does not exercise its
right of first refusal hereunder, and the Property is sold to a third party, the
right of first  refusal set forth  herein shall  terminate  and be of no further
force or effect.  Notwithstanding the terms of any offer received by Landlord to
purchase the Property  from a third party,  the purchase  agreement  provided by
Landlord to Tenant  hereunder  shall  provide  that Tenant  shall  purchase  the
Property "As  Is,"without  any  representation  or warranty by Landlord.  Tenant
shall close the escrow on the  purchase of the  Property  within sixty (60) days
after it notifies Landlord in writing of Tenant's acceptance of Landlord's offer
to sell the Property to Tenant hereunder.

40.      OPTION TO PURCHASE PROPERTY.

         A. Subject to the terms and  conditions  hereof and  provided  that the
Property has not been previously conveyed to a third party pursuant to the terms
set forth in Paragraph 40 above,  Tenant shall have an option (the  "Option") to
purchase  the  Property.  The Option  shall be  exercised,  if at all, by Tenant
delivering written notice of its exercise of the Option to Landlord prior to the
earlier of (i) the date ninety (90) months after Landlord  acquires title to the


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<PAGE>

Property,  or (ii) the date of Tenant's  election  not to exercise  its right of
first refusal  under  Paragraph 39 hereof if the Property is in fact sold to the
third party pursuant to the terms and conditions set forth in the right of first
refusal  notice.  In the event  Tenant  shall  fail to  deliver  written  notice
exercising the Option when required,  the Option shall  automatically  terminate
and be of no further force or effect.  Tenant may not exercise the Option during
any period of an Event of Default  under this  Lease.  If Tenant  exercises  the
Option in a timely manner, Landlord shall be obligated to sell, and Tenant shall
be obligated to purchase,  the Property, as hereinafter  provided.  The purchase
price (the  "Purchase  Price") for the Property  shall be the greater of (i) the
Property's  appraised  fair market  value,  as determined in Paragraph 40B below
reduced by an amount  equal to the total of all  supplemental  payments  paid by
Tenant to Landlord under the provisions of Paragraph 6.2 of this Lease,  or (ii)
the then  current net book value of the  Property  as carried on the  Landlord's
books.

        B. If the Tenant  exercises the Option,  Tenant and Landlord each shall,
within ten (10) business days from the date Tenant notifies Landlord of Tenant's
exercise of the Option, appoint a real estate appraiser who shall be a member of
the American  Institute of Real Estate Appraisers  ("AIREA") and such appraisers
shall each  determine  the fair  market  value of the  Property,  including  all
improvements thereon. Each such appraiser shall have no less than five (5)years'
experience  appraising   commercial  property  in  Kelso,   Washington  and  the
surrounding  County. Such appraisers shall, with twenty (20) business days after
their appointment,  complete their appraisals and submit their appraisal reports
to Landlord  and Tenant.  If the fair market  value  established  in the two (2)
appraisals  varies by five  percent  (5%) or less of the higher  appraisal,  the
average of the two shall be  controlling.  If said fair market  value  varies by
more than five percent (5%) of the higher  value,  said  appraisers,  within ten
(10)  days  after  submission  of the  last  appraisal,  shall  appoint  a third
appraiser  who shall be a member of the AIREA and who shall also be  experienced
in the appraisal of commercial properties in the vicinity of the Property.  Such
third appraiser  shall,  within twenty (20) business days after his appointment,
determine by appraisal the fair market value of the Property taking into account
the same factors  referred to above, and submit his appraisal report to Landlord
and Tenant.  The fair market value  determined  by the third  appraiser  for the
Property  shall be  controlling,  unless  it is less  than that set forth in the
lower appraisal previously  obtained,  in which case the value set forth in said
lower  appraisal  shall be  controlling,  or unless it is greater  than that set
forth in the higher appraisal previously obtained,  in which case the rental set
forth in said higher  appraisal  shall be  controlling.  The appraisal shall not
take into account any costs expended by Tenant after the Lease Commencement Date
for  construction  of  additional  buildings or building  additions  and for the
build-out of the second floor of the administration building. If either Landlord
or Tenant fails to appoint an appraiser,  or if an appraiser appointed by either
of them  fails,  after his  appointment,  to submit  his  appraisal  within  the
required period in accordance with the foregoing, the appraisal submitted by the
appraiser  properly  appointed  and timely  submitting  his  appraisal  shall be
controlling.  If the two appraisers  appointed by Landlord and Tenant are unable
to agree upon a third  appraiser  within the required  period in accordance with
the foregoing,  application  shall be made within twenty (20) days thereafter by
either  Landlord or Tenant to the AIREA,  which  shall  appoint a member of said
institute  willing to serve as appraiser.  The cost of all appraisals under this
subparagraph shall be borne equally by Landlord and Tenant.


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<PAGE>

        C. Once the Purchase Price has been determined by the parties,  close of
escrow  shall take place  sixty  (60) days  thereafter.  At the close of escrow,
Landlord  shall  convey fee title to the  Property to Tenant "As Is" and without
warranty  or  representation.  The  Purchase  Price  shall be paid by  Tenant to
Landlord  in cash at the close of escrow.  Seller  shall pay its normal  closing
costs,  including title insurance premiums,  real estate excise taxes, and other
transfer  taxes.  Purchaser  shall  pay  its  normal  closing  costs,  including
recording of the Deed and recording of any loan  documents  and title  insurance
for any lender that may be involved in financing the cash Purchase Price. Seller
and Purchaser shall each pay one-half of the escrow fees.

        D. The Option  rights set forth in this  Paragraph  40 are  personal  to
Tenant and may not be  transferred  or  assigned,  except in  connection  with a
Permitted Transfer.

                                       LANDLORD:
                                       EMCON,
                                       a California corporation

Date: 4/4/97                           By: /s/R. Michael Momboisse
     ------------------------------       ------------------------------------

                                       Its:   CFO & VP Legal
                                           -----------------------------------
                                       TENANT:
                                       COLUMBIA ANALYTICAL SERVICES, INC.
                                       a Washington corporation

Date:    4/4/97                        By:  /s/Steven W. Vincent
     -----------------------------        -----------------------------------
                                      
                                       Its:  President
                                            ----------------------------------





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<PAGE>





State of Washington        On April 4th, 1997
County of Cowlitz
                           Before me,
                           personally  appeared  Stephen W.  Vincent, 
                           President  of Columbia Analytical Services, Inc.,

                           personally  known  to  me to be
                           the   person   whose   name  is
                           subscribed    to   the   within
                           instrument, and acknowledged to
                           me that he executed the same in
                           his  authorized  capacity,  and
                           that  by his  signature  on the
                           instrument  the person,  or the
                           entity upon behalf of which the
                           person   acted,   executed  the
                           instrument.

                           WITNESS  my hand  and  official
                           seal.

                           __________________________________
                           Notary's Signature


State of Washington        On April 4th, 1997
County of Cowlitz
                           Before me,
                           personally  appeared R,  Michael  Momboisse,  
                           the Chief  Financial Officer and Vice President
                           of EMCON,

                           personally  known  to  me to be
                           the   person   whose   name  is
                           subscribed    to   the   within
                           instrument, and acknowledged to
                           me that he executed the same in
                           his  authorized  capacity,  and
                           that  by his  signature  on the
                           instrument  the person,  or the
                           entity upon behalf of which the
                           person   acted,   executed  the
                           instrument.

                           WITNESS  my hand  and  official
                           seal.


                           _____________________________________
                           Notary's Signature


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