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                                                                    Exhibit 10.1

                            SECOND AMENDMENT TO LEASE

         This is a Second  Amendment  to Lease,  dated  the 31st day of  August,
1998,  to that  certain  Lease  Agreement,  ("Lease")  executed  the 11th day of
November,  1996, by and between T. BRYAN ALU AND CHARLES HURTH, JR., hereinafter
called "Landlord" and TENERA, INC., hereinafter called "Tenant".

         NOW, THEREFORE, for and in consideration of the premises and the mutual
covenants and agreements  contained herein, the receipt and sufficiency of which
are hereby acknowledged, Landlord and Tenant agree as follows:

AMENDMENT ITEM NO 1: EXTENSION OF LEASED PREMISES

         The term of the lease shall be  extended  for an  additional  period of
approximately  two (2)  years  and one (1)  month at the base  rate of $8.75 per
square foot per year for the leased  premises  and the  expansion  space  herein
noted and shall commence following the current tenant's vacation of the premises
and  Landlord's  completion  of its finished  obligation  pursuant to Item No. 5
herein,  expected to be October 15, 1998 (Commencement  Date) and will expire at
11:59 on October 31, 2000, pursuant to Section 1.4 of the Lease.

AMENDMENT ITEM NO. 2:  EXPANSION OF LEASED PREMISES

         The original  Leased  Premises is modified to be 4,171 square feet,  as
shown on the attached  floor plan  (Exhibit A).  Additionally,  landlord  hereby
leases to Tenant,  and Tenant  hereby  leases from  Landlord,  2,382  additional
square  feet  (the  "Expanded  Premises")  as shown on  Exhibit  A and after the
Commencement  Date, as defined herein, the term "Leased Premises" as defined and
used in the Lease  shall be  deemed  to mean and  include  the  original  Leased
Premises covered by the aforementioned Lease, plus the Expanded Premises.

AMENDMENT ITEM NO. 3:  BASE RENT

Base Rent due on the Leased  Premises  shall be an amount equal to $4,778.23 per
month,  based on the  rental  rate of $8.75 per  square  foot per annum on 6,553
square  feet.  This rate shall  escalate  annually by four  percent  (4%) on the
anniversary dates of the lease and throughout any option periods.

AMENDMENT ITEM NO. 4: BUILDING MAINTENANCE

         Pursuant  to Article 11 of the Lease and as  amended  herein,  Landlord
shall  maintain  both interior and exterior of the building  including,  but not
limited to, window cleaning, pest control,  landscaping grounds and snow removal
from  parking  areas and  sidewalks.  The costs for these  items  will be passed
through to Tenant as an operating  expense  pursuant to Article 6.2 of the Lease
(Landlord  will  reconcile  all costs  annually  and provide  Tenant with a full


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accounting  of all costs) and as amended  herein,  along with a mutually  agreed
management fee of $.25 per square foot per year.  Effective on the  Commencement
Date, the Tenant's  pro-rata share of operating  costs as defined in Section 1.2
of the Lease will be amended to equal 27.3%.

         For  reasons  of  clarity,  it is  hereby  noted  that  the  Tenant  is
responsible for the following items including, but not limited to signage, trash
removal, janitorial, security agreements, and insurance pursuant to Section 9 of
the  Lease.  Tenant  shall  also have the  carpet  within  the  Leased  Premises
professionally cleaned upon the termination of the Lease.

AMENDMENT ITEM NO. 5:  TENANT IMPROVEMENTS

         Prior to the  commencement  date hereof,  Landlord shall  re-carpet the
expanded portion of the premises with a carpet of similar quality to that in the
original space, as shown on the attached Exhibit A, and repaint where necessary.
Additionally,  Landlord shall replace the stained  vertical blinds in the entire
leased premises and shall replace any stained or missing ceiling tiles.

AMENDMENT ITEM NO. 6: OPTION TO RENEW

         So long as Tenant is not in default of this  lease,  Tenant  shall have
the  option to extend  this  lease for two (2) terms of one (1) year  each.  The
lease rate shall escalate by four percent (4%) for each of these option periods.
Tenant shall provide  Landlord one hundred  twenty (120) days written  notice of
its intent to so renew.

AMENDMENT ITEM NO. 7:  ALL OTHER TERMS AND CONDITIONS

Except as set forth herein,  all of the terms and provisions of the Lease,  from
and after the Commencement  Date, shall be applicable to the Expanded  Premises,
as well as the original Leased Premises.  Except as modified  hereby,  the terms
and  provisions of the Lease are hereby  ratified and agreed to be in full force
and effect. In the event of a conflict between the Second Amendment to the Lease
and the Lease, the Second Amendment to Lease shall control.

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

LANDLORD:                                            TENANT:
                                                     TENERA, INC.

/s/ T. Bryan Alu                            /s/ William S. Glover
------------------                          ---------------------
Its President of TENERA Rocky Flats, LLC

                                            /s/ Jeffrey R. Hazarian
                                            -----------------------
                                            Executive Vice President and Chief
Financial Officer