November 21, 2020: 2-page nontechnical flyer summarizing why Ketterer’s hot particles pose negligible risks.

New detailed document on Dr. Michael Ketterer’s measurements of hot particles in Rocky Flats soil. His claims that “Particles of these dimensions…present a grave hazard for human inhalation and pulmonary retention” do not hold up, because the dose from a single particle is tiny and they are not very common in soil.

Final results from the Jefferson Parkway (and other) soil sampling projects: Parkway, Greenway, Ketterer:

An overview of the “hot sample” found mid-August 2019 during Jefferson Parkway soil sampling.

David Wood’s presentation to Candelas residents (10 MB); slightly more verbiage, same slides.

Broomfield City Council exchanges

DMW has attempted to counter (for the Broomfield City Council) misinformation in letters from an anti-Refuge partisan.  The attached (with name redacted) documents address particular issues.  Contact me for the letters from The Other Side to which these were responses.

Trust experts from 70’s? Cancer cases downwind? Overlooked alpha radiation? Gross problems in `cancer surveys’.

1 hot particle and cancer? Relevance of alpha microbeam experiments? Alpha radiation not understood?


Apart from the Big Picture and INSIDE THE REFUGE documents, we recommend that the science documents be read in order. Suggested background reading is given at the beginning of each; references are at the end.  There is a brief table of contents for each at the beginning.  The choice of PDFs for documents is made necessary by the need to mingle graphics, occasional math, marginal remarks an an extensive bibliography.

If you click on the green document link a new full-page PDF browser view will pop up.  By clicking on the file thumbnails, these PDF files will display as normal content (of a size intended for online reading, not a printout) in your browser window without the need to fire up Acrobat Reader or other browser plugins.  A small control panel that permits you to download the file is present at the bottom of the viewing window; by toggling full screen you can go back to this file list.


These are summary documents that do not require having read in detail the documents farther down.

A parable: Why do you drink municipal water?

Take a step back from radiation to a possibly more familiar situation.

Executive summary

Read this if you’re in a rush.

Inside the refuge

New [May/June 2019] documents answer the questions “What radioisotopes are in Refuge soil?” and “What are measured radiations levels on the trails and even inside the off-limits DOE “central operable unit”?”  Brief flyers gives a non-technical summary of results.

Natural soil radioactivity

More than 97% of Refuge soil (and thus, in windblown dust) radioactivity is due to naturally occurring isotopes common along the Front Range.

On the trails

The ADER [“ambient dose equivalent[radiation] rate”] measured in April 2019 is entirely consistent with ordinary background radiation along the Front Range, nor are there “hot spots” on the trails.

Inside the “Central Operable Unit” 

The COU is the ‘donut hole’ administered by the Department of Energy).  Data courtesy of Kim Griffiths, a member of the Rocky Flats Stewardship Council who visited the COU on June 10th 2019.

The ADERS [“ambient dose equivalent[radiation] rate”] measured in April 2019 is entirely consistent with ordinary background radiation along the Front Range, nor are there “hot spots” on the trails.

Summary flyers

These two non-technical pages summarize why the ordinary background radiation levels in the Refuge are no surprise.

A non-technical single page about the COU visit data.

Documents about the science

Click on the green link to open a separate window showing the PDF file.  Click in the ringed purple oval to view the document “in line” in your current browser page.

Seeking clarity in Fall 2013

DMW’s 2013 experience before buying a house in Candelas.

How people think about radiation

Background on people’s reactions to radiation and risk and how repetition can crowd out truth.

A crash course in radiation, biology, and health physics

Almost everything you need to know to read articles about radiation and health.

Cancer epidemiology

Your risks of cancer are largely determined by your lifestyle; radiation is a small contributor.

From radiation dose to cancer risk

How risk is quantified and how radiation-induced cancer has been monitored. A quick introduction to RESRAD, the tool used by the Department of Energy and others in the US and abroad for assessing dose and risk.

Radiation doses: large, small, and unavoidable

Put your exposure to radiation from Rocky Flats in perspective.  Despite the highest background radiation rates in the US, cancer rates in Colorado are among the lowest.

Rocky Flats, radiation, and risk

The most important document on our site.  The ‘ground truth’ for those who live around the former Rocky Flats, the famous maps, and radiation dose estimates `by hand’ and using RESRAD, the software used by the US Department of Energy and other entities around the world.

Four simple radiation dose estimates

The estimates themselves (simple math) and a sample check of RESRAD

‘Recent’ developments in low-dose radiation response

The ‘linear, no-threshold’ (LNT) hypothesis , used around the world for radiation mitigation, has been relegated to a regulatory standard determining mitigation levels, not a predictor of cancer risk, which it very likely overestimates at the extremely low doses relevant to the Rocky Flats area.

Common misinformation

Frequently raised concerns include

  • Risks due to ‘hot particles’ were plausible 40 years ago; they were discredited in the mid 1970s and later.
  • Alleged “cancer clusters” around Rocky Flats.  Cancer clusters are very hard to identify.  While downwinders unquestionably were harmed by the history of the Rocky Flats plant, those moving into new developments are not.
  • Uncertainties about the redistribution of Pu by burrowing animals
  • The need to ‘tie the hands’ of the Fish and Wildlife Service about what the need for prescribed (controlled) burns to avoid prairie wildfires within the Wildlife Refuge because of alleged risks due to redistributed or inhaled Pu from ash.

These issues are addressed in Hot particles: Nevermore, Cancer clusters (with suggestions to Downwinders for how to make their case stronger, including software), and  Burrowing critters and burning vegetation.

Hot particles

Highly radioactive inhaled small particles have not been regarded as a special risk since the mid 1970s.

Cancer clusters

Pockets of high cancer rates are extremely hard to demonstrate reliably.  Tools to try.

Burrowing critters and burning vegetation

Simple estimates of why burrows just don’t matter but fires might.  All the more reason to let Fish&Wildlife do its job.

Geiger-Muller counters can’t detect alpha particles

Nonsense! A pancake design with a mica window most certainly can.  I refute it thus