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| Human-Intrusion Standard | 197.25 – 197.26 | |||||||
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Sec. 801, Pub. L. 102-486, 106 Stat. 2921, 42 U.S.C. 10141 n.
66 FR 32132, June 13, 2001, unless otherwise noted.
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Subscribe to: 40 CFR Part 197 Subpart B - Human-Intrusion Standard
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(a) The DOE must determine the earliest time after disposal that the waste package would degrade sufficiently that a human intrusion (see § 197.26) could occur without recognition by the drillers.
(b) The DOE must demonstrate that there is a reasonable expectation that the reasonably maximally exposed individual will receive an annual committed effective dose equivalent, as a result of the human intrusion, of no more than:
(1) 150 microsieverts (15 millirems) for 10,000 years following disposal; and
(2) 1 millisievert (100 millirems) after 10,000 years, but within the period of geologic stability.
(c) The analysis must include all potential environmental pathways of radionuclide transport and exposure.
[73 FR 61288, Oct. 15, 2008]
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.