CFR > Title 10 - Energy > CHAPTER I—NUCLEAR REGULATORY COMMISSION > PART 63—DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA > SUBPART L—Postclosure Public Health and Environmental Standards (§63.301 to §63.343) > 63.331—Separate standards for protection of ground water.

63.331—Separate standards for protection of ground water.

DOE must demonstrate that there is a reasonable expectation that, for 10,000 years of undisturbed performance after disposal, releases of radionuclides from waste in the Yucca Mountain disposal system into the accessible environment will not cause the level of radioactivity in the representative volume of ground water to exceed the limits in the following Table 1:
Table 1—Limits on Radionuclides in the Representative Volume
Radionuclide or type of radiation emitted Limit Is natural backgroundincluded?
Combined radium-226 and radium-228 5 picocuries per liter Yes.
Gross alpha activity (including radium-226 but excluding radon and uranium) 15 picocuries per liter Yes.
Combined beta and photon emitting radionuclides 0.04 mSv (4 mrem) per year to the whole body or any organ, based on drinking 2 liters of water per day from the representative volume No.