sc-8. CHANGES IN WORK: The Commission may at any time by a written order, require changes be made to the spec- {fications and/or drawings, change the location of the work, omit certain work and/or require additional work. Sc-9. DISPOSAL OF EXISTING INSTALLATIONS: . Construction covered by these specifications Involves demolition, Structures, removal or salvage of existing construction. including Quonset buildings, concrete slabs on earth, and all other existing installations shall be demolished and removed as required by the new construction, and waste materials therefrom disposed of in a manner ap-~ proved by the Contracting Officer. Existing Quonset buildings, at the Contractor's option, may be removed, repaired as required and relocated for warehousing uses or other uses approved by the Contracting Officer; and such buildings shall remain the property of the Government. The work shall include renovating and repairing certain other installations; the number and location of such installations and the extent of the repairs thereto to be determined by the Contracting Officer. SC-10. SECURITY MEASURES: a. Work in Classified Areas: All Contractor's employees shali require a clearance and identification badge or card as provided in paragraph GC-II-2 of the General Conditions. b. Safeguarding Classified Property, Materials and Documents: Special measures shall be taken by the Contractor in the protection of an accounting for classi- fied materials, in accordance with applicable regulations and policies of the Commission. SC-11. RATES OF WAGES: The wages or salaries to be paid employees on this project, as determined by the Secretary of Labor to be prevailing for the corresponding classes of employees employed on projects of a character similar to the contract work in the pertinent locality, shall be as set forth in Exhibits A, B and C below. Rates of wages shall be subject to revision as determined by the Secretary of Labor to conform to changes in prevailing conditions, subject to subsequent approval of the Contracting Officer. SC-5