Total BS. Where the hell did you get that bit of misinformation?
http://www.nrc.gov/reactors/operating/ops-experience/tritium/sites-grndwtr-contam.html
http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/tritium-radiation-fs.html\
Tritium is cumilative, the feds have turned off the monitors - it's not rocket science.