Each statement is either commonly made or makes an important point.  There's a brief explanation below and a link (blue book) to the document in which the issue is carefully discussed with references to textbooks, reference articles, or scientific journal articles.  Hare-brained claims are mentioned here.

  • Inhalation of a single plutonium 'hot particle' is enough to cause cancer.

After a 1965 fire, workers at Rocky Flats each inhaled 10,000 to 100,000 0.6 μ hot particles with no detectable cancers 10 years later.  
  • There are buried barrels and radioactive hot spots scattered over the Refuge.

Hearsay.  The cleanup required very detailed maps of every feature within the COU precisely so that the DOE can monitor the cleanup features.
  • Geiger counters can measure alpha particles

High-end Geiger-Muller counters have a thin mica window that permits alpha particles to be detected provided they are within range (a couple of inches).
  • Plutonium is the dominant source of soil radiation at Rocky Flats.

In fact Pu isotopes contribute less than 1% of total soil radioactivity
  • No cleanup has ever taken place outside of the Rocky Flats Superfund site.

True. Pu levels throughout almost all of the Refuge are far below federal soil limits.
  • A long half-life is more dangerous to human health than a short one.

Radioactivity and half-life are inversely proportional.  Many natural radioisotopes have half-lives of million or even billions of years.  Short half-life isotopes are much more radioactive, so are often used in medical imaging.
  • Nuclear radiation produces rare cancers.

At present there are no known differences between cancers occurring naturally or produced by exposure to nuclear radiation.  Such radiation produces ordinary cancers, though leukemias are a 'canary in the coal mine' indicator of a radiation problem.
  • Candelas and other housing developments are built on a Superfund site

The Superfund cleanup area was a small part of the COU, itself now fully surrounded by the Refuge.
  • The incidence of prostate cancer is higher in wealthy neighborhoods.

Wealthy people can afford better medical care, so are diagnosed much more often. This is a typical 'confounding variable' in epidemiology, like smoking and lung exposure to nuclear radiation. Thus careful epidemiology requires 'controlling' carefully for such variables.