[Code of Federal Regulations] [Title 10, Volume 1] [Revised as of January 1, 2001] From the U.S. Government Printing Office via GPO Access [CITE: 10CFR39.53] [Page 607] TITLE 10--ENERGY CHAPTER I--NUCLEAR REGULATORY COMMISSION PART 39--LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING--Table of Contents Subpart C--Equipment Sec. 39.53 Energy compensation source. The licensee may use an energy compensation source (ECS) which is contained within a logging tool, or other tool components, only if the ECS contains quantities of licensed material not exceeding 3.7 MBq [100 microcuries]. (a) For well logging applications with a surface casing for protecting fresh water aquifers, use of the ECS is only subject to the requirements of Secs. 39.35, 39.37 and 39.39. (b) For well logging applications without a surface casing for protecting fresh water aquifers, use of the ECS is only subject to the requirements of Secs. 39.15, 39.35, 39.37, 39.39, 39.51, and 39.77. [65 FR 20345, Apr. 17, 2000]