40 C.F.R. § 141.55
Maximum contaminant level goals for radionuclides.
Cite as 40 C.F.R. § 141.55 (2026)
MCLGs for radionuclides are as indicated in the following table: Contaminant MCLG 1. Combined radium-226 and radium-228 Zero. 2. Gross alpha particle activity (excluding radon and uranium) Zero. 3. Beta particle and photon radioactivity Zero. 4. Uranium Zero. [65 FR 76748, Dec. 7, 2000]