TO FORM 10-K OF WELLS REAL ESTATE FUND VII, L.P. FOURTH AMENDMENT TO LEASE

EXHIBIT 10(uu)

TO FORM 10-K OF

WELLS REAL ESTATE FUND VII, L.P.

FOURTH AMENDMENT TO LEASE

THIS FOURTH AMENDMENT TO LEASE (this “Amendment”), dated as of the 15th day of August, 2004 (the “Effective Date of Amendment”), by and between FUND VII AND VIII ASSOCIATES, a Georgia joint venture (“Landlord”), and CH2M HILL , a Florida corporation (“Tenant”).

BACKGROUND

The original lease agreement was entered into with an effective date of September 20, 1994, by and between Wells Real Estate Fund VII, L.P. a Georgia limited partnership (“Fund VII”) and Tenant, with respect to those premises situated in that certain building located at 3011 SW Williston Road, Gainesville, Florida 32608, being more particularly described on Exhibit “A” attached hereto (the “Property”). The original lease was then amended pursuant to that certain First Amendment to Lease dated November 14, 1994, that certain Second Amendment dated January 12, 1995 and that certain Third Amendment dated June 30, 1995 (the original lease, together with all amendments, is called the “Lease”). Subsequently, Fund VII contributed the Property into a joint venture pursuant to that certain Joint Venture Agreement of Fund VII and Fund VIII Associates dated February 10, 1995 between Fund VII and Wells Real Estate Fund VIII, a Georgia limited partnership (“Fund VIII”), as amended by that certain First Amendment to Joint Venture Agreement of Fund VII and Fund VIII Associates dated April 1, 1996.

Landlord and Tenant now wish to amend the Lease as described below.

AGREEMENT

NOW, THEREFORE, for and in consideration of the mutual covenants and benefits herein contained, Landlord and Tenant do hereby agree as follows:

1. Definitions . Capitalized terms used in this Amendment but not otherwise defined herein shall have the meanings given in the Lease.

2. Demised Premises . From and after September 1, 2004 (the “Extension Date”) the Demised Premises shall mean that certain premises in the Building located on the Land more particularly described on Exhibit “B” attached hereto, which consist of approximately 50,877 square feet of Rentable Floor Area, having been measured according to BOMA standards. In addition, the Rentable Floor Area of the Building is 61,494, so that Tenant’s Share is 82.73%.

3. Termination of Lease as to Surrendered Space . Landlord and Tenant agree that Tenant’s obligation to pay Rent pursuant to the Lease shall be terminated as it relates to the approximately 5,500 square feet more particularly described on Exhibit “C” attached hereto (the “Surrendered Space”) effective as of 11:59 p.m. on August 31, 2004 (the “Termination Date”).

Notwithstanding the foregoing, Tenant shall remain in the Surrendered Space subject to the Lease until Landlord has completed Leasehold Improvements as per Paragraph 7 of this Fourth Amendment to Lease. Upon completion of such Leasehold Improvements, Tenant will vacate and surrender possession of the Surrendered Space to Landlord pursuant to Section 30 of the Lease. From and after such vacating and surrender, Tenant will have no further right to occupy the Surrendered Space, the Lease as it relates to the Surrendered Space will be terminated, and Tenant will have no further obligations for the Surrendered Space.

4. Extension of Lease Term . Commencing on the Extension Date the Lease Term shall hereby be extended for a period of seventy-five (75) months and shall expire on November 30, 2010 (the “Expiration Date”) unless renewed or extended as otherwise provided herein.

5. Base Rental Rate . From and after the Extension Date, the Base Rental Rate will be a gross payment of base rent and operating expenses, and such payment shall be due and payable as set forth in Section 5 of the Lease as modified herein in the following amounts, subject to adjustments as specified within this Fourth Amendment to Lease.

6. Tenant’s Additional Rental . Section 7(b) of the Lease is hereby amended so that Tenant’s Share of Operating Expenses shall be defined as Tenant’s Share of the total dollar increase, if any, in Operating Expenses paid or incurred by Landlord in each calendar year over the Operating Expenses paid or incurred by Landlord in the calendar year 2005 (the “Base Year”). Notwithstanding the foregoing, Landlord shall limit the Operating Expenses effective 9/1/2004 through 12/31/2005 at an annual rate of $7.00/square foot, and for subsequent years during the term of the lease, Landlord shall limit annual increases to Operating Expenses to 3%, except as provided herein. Landlord’s limit of Operating Expenses shall not include electrical costs, real estate taxes or insurance expense and any other expenses outside the reasonable control of Landlord (the “Excluded Operating Expenses”), however, such Excluded Operating Expenses shall be limited to actual expenses as reasonably incurred by the Landlord in the normal operation of the Building and the Property.

7. Leasehold Improvements .

(a) Except as set forth in this Section, Tenant accepts the Demised Premises in their “as is” condition on the date that this Amendment is entered into. Landlord agrees to

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complete certain work (the “Work”), at Landlord’s cost and expense, consisting of the following items: (i) installing carpet on the floors and painting the walls of the Demised Premises, using Building standard materials or as otherwise noted in this Amendment; (ii) installing card access security systems to control eight (8) access points; (iii) and constructing six (6) demised offices pursuant to space plans, (collectively, the “Plans”), attached hereto as Exhibit “D”. All changes, additions and modifications to the Work or the Plans shall be at Tenant’s sole cost and expense (including, without limitation, materials above Building standard and compliance issues necessitated by Tenant’s use and occupancy of the Demised Premises). All changes in the Work or the Plans must receive the prior written approval of Landlord, and the cost thereof shall be borne solely by Tenant. It shall be a condition precedent to Landlord’s commencement of the Work that Tenant remit to Landlord payment for all any additional costs due to changes of the Work or Plans and any failure to do so shall be a delay caused by Tenant.

(b) Landlord shall also provide to Tenant an additional allowance, payable by Landlord to Tenant upon execution of this Fourth Amendment to Lease, the sum of $52,000 for Tenant’s use as Tenant requires for moving, cabling and any other costs and expenses related to this Fourth Amendment to Lease.

8. Right of First Offer . Section 49 (a) and (b) of the Lease is deleted and replaced with the following:

“(a) So long as (i) there are more than twenty-four (24) months remaining in the Lease Term, and (ii) a period of one (1) year has expired since the Effective Date of this Amendment, at such time or times that all of the space described in Exhibit “E” (the “First Offer Space”) becomes vacant, Landlord will notify Tenant in writing of the availability of such space. So long as Tenant provides written notice to Landlord, within ten (10) days after receipt of Landlord’s notice, of Tenant’s election to expand the Demised Premises to include the First Offer Space (the “Election Notice”), then the parties hereto shall proceed to execute an amendment to this Lease to add the First Offer Space to the Demised Premises within thirty (30) days of Landlord’s receipt of the Election Notice. If Tenant fails to (i) deliver the Election Notice to Landlord on or before the expiration of such ten (10) day period described above, or (ii) execute an amendment to the Lease to add the entire First Offer Space to the Demised Premises within such thirty (30) day period, Tenant will be deemed to have waived its Right of First Offer and, for a period of one (1) year from such failure, Landlord may lease all or a portion of the First Offer Space to any third party without notice to Tenant or without Tenant’s consent. If such one (1) year period expires before Landlord leases all or any portion of the First Offer Space to a third party, then Landlord must notify Tenant that the First Offer Space is available and repeat the process above before leasing all or any portion of the First Offer Space to any third party. This Right of First Offer is personal to Tenant and is not transferable by Tenant.

(b) If Tenant leases the First Offer Space pursuant to this Right of First Offer, the same will be added to the Demised Premises as of the date of Landlord’s receipt of the Election Notice, and all of the terms and conditions of the Lease, including the Lease Term and the then current Rent, will apply to the First Offer Space; provided, however, Landlord will not be obligated to grant any concessions or allowances with respect to the First Option Space. Upon the effective date of any amendment to the Lease entered into as a result of Tenant’s Right of

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First Offer, Tenant’s Share, Rent and any other calculation pertaining to the Rentable Floor Area of the Demised Premises will be recalculated based on the addition of the First Offer Space to the same.

(c) Tenant will not have any rights according to this Section if, at t