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Reporting radionuclide mixtures if composition is unknown

How are mixtures of radionuclides reported if the composition of the mixture is unknown?

If the composition of the radionuclide mixture is unknown, there are two main possibilities: (1) the identity of the radionuclides is known but the quantities of one or more of the radionuclides released are not; or (2) the identity of one or more of the radionuclides released is not known. In the first situation (identity known, but quantity unknown), the RQ for the mixture is the lowest RQ of any radionuclide in the mixture. In the second situation (identity of radionuclides unknown), the release must be reported if the total release is equal to or greater than 1 Ci, or if the total release is equal to or greater than the lowest RQ of any known radionuclide in the mixture, whichever is lower.

Emergency Planning and Community Right-to-Know Act (EPCRA)

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Last updated on April 18, 2025
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