[Code of Federal Regulations] [Title 40, Volume 24] [Revised as of July 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR197.26] [Page 66-67] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 197_PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA--Table of Contents Subpart B_Public Health and Environmental Standards for Disposal Sec. 197.26 What are the circumstances of the human intrusion? For the purposes of the analysis of human intrusion, DOE must make the following assumptions: (a) There is a single human intrusion as a result of exploratory drilling for ground water; (b) The intruders drill a borehole directly through a degraded waste package into the uppermost aquifer underlying the Yucca Mountain repository; (c) The drillers use the common techniques and practices that are currently employed in exploratory drilling for ground water in the region surrounding Yucca Mountain; (d) Careful sealing of the borehole does not occur, instead natural degradation processes gradually modify the borehole; (e) Only releases of radionuclides that occur as a result of the intrusion and that are transported through the resulting borehole to the saturated zone are projected; and (f) No releases are included which are caused by unlikely natural processes and events. [[Page 67]] Ground Water Protection Standards