How much is too much?

The other day I read a blog post about what different levels of radiation do to people, located here.  It is also a good place to talk about the radiation levels expected around Yucca Mountain.  Workers around Yucca Mountain are expected to have an extra .15 to .20 mSv of radiation per year.  As you can see from the chart, this is equivalent to a couple of chest x-rays.  Residents in the surrounding area would experience a negligible change in dose from the standard background radiation, which is around 3.4 mSv per year.