§ 569a. Temporary employment of experts or consultants; compensation
The Chief of Engineers is authorized to procure the temporary or intermittent services of experts or consultants or organizations thereof in connection with civil functions of the Corps of Engineers without regard to chapter 
51 and subchapter 
III of chapter 
53 of title 
5: Provided, That individuals so engaged may be paid at rates not to exceed the daily equivalent of the rate for GS–18 for each day of their services.