Local geographic gamma counting- how is your soil?

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Jon Rosenstiel
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Re: Local geographic gamma counting- how is your soil?

Post by Jon Rosenstiel » Wed Sep 18, 2019 5:39 pm

Over the years I’ve also accumulated some other interesting soil and sand samples. I don’t recall who sent me the Amelia Co. VA river sand, but the Tokyo gutter dirt and the Guarapari (Brazil) beach sand was sent to me by youtuber bionerd23.
Soil comparisons, with sand.pdf
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Tokyo gutter dirt.jpg
Jim, I wanted to look for evidence of the latest Russian nuclear fiasco, but my hpGe system is shut down for the summer. I just now grabbed a wipe, will run it on the hpGe when I fire up my system later this year.

Thank you for the kind words.

Jon Rosenstiel
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Richard Hull
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Re: Local geographic gamma counting- how is your soil?

Post by Richard Hull » Thu Sep 19, 2019 12:02 am

Jon,

That Amelia Co. sand probably did not come from a river, but a stream running on a farm about 30 miles west of Richmond and just west of Amelia Courthouse in the town of Amelia. We have worked it for some time now for the monazite sand. Most of the local collectors are myself, T.R. Leary, Tim Raney and Bill Kolb. You might have received it from one of us at a big HEAS October event when you were here.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

Hunter Long
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Re: Local geographic gamma counting- how is your soil?

Post by Hunter Long » Thu Sep 19, 2019 7:19 pm

So the hot spot I found in the video had no rock outcroppings, the soil itself contains a lot of Thorium (probably similar in composition to the Amelia Co. sand you have). This paper: https://dmme.virginia.gov/commercedocs/PUB_38.pdf led me to the spot (it's labeled #2) and they said the soil contains 330 to 583 ppm equivalent uranium (eU) and 10,500 to 11,000ppm equivalent thorium (eTh) based on lab gamma-ray analysis. I scooped up a zip-lock bag of the dirt and it makes the 2" pancake geiger probe read around 2kcpm when I hold it up to it.

More good resources for VA people: https://www.dmme.virginia.gov/dgmr/uranium.shtml

One of these papers also mentions a hot spot in Powhatan, VA where there is now a big solar farm.

I added some pictures to my blog https://hunterwlong.com/mapping-radiati ... -detector/ that show how the different pavements on a road have different levels of radiation. Here's my favorite one:

Capture.PNG

My next project is going to be doing a survey of the UVA campus near where I live. There are two buildings in particular I'm interested in, one held a research nuclear reactor and one is where an ultracentrifuge was used to develop the uranium enrichment process (I read about them both here: https://uvamagazine.org/articles/the_cerenkov_blue). Doubt I'll find anything, but the two buildings are within about 200 yards of each other. I've replaced the paint can with electrical tape and shrink tubing so that it can now be carried around in a sachel under my arm as I walk around. Hopefully a lot less conspicuous. I've also reduced the pulse threshold. It now registers about 100cps instead of 20cps and is now sensitive to the 59kev gammas from a smoke detector that it used to ignore completely. Not sure if this will increase sensitivity or just make everything more noisy.

-Hunter

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Richard Hull
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Re: Local geographic gamma counting- how is your soil?

Post by Richard Hull » Fri Sep 20, 2019 5:34 am

I did a search of the literature and came up with an amazing item. As 90% of the thorium here is in Monazite and all monazite tends to form in 3 distinct belts from Georgia thru Virginia, I submit two maps that stunned me.

Richmond is located at the exact juncture or collision of two of these belts! Charlottesville area is on the western belt or the mountain belt #1.

See the two maps below. The large portion shows the three monazite belts on the eastern seaboard and names them in the upper left box.
The smaller (blowup), shows the collision or juncture of the belts #2 and #3 at the city of Richmond and the counties surrounding it of Henrico, Amelia, Goochland, Powhattan, Dinwiddie, and Chesterfield.
The hot park I visit is in Henrico. I actually live in Henrico about 1 mile beyond the city limit. This blew me away. I live on the confluence of two major Thorium mineral deposits! The really hot stuff is just a mile or two west of me all the way out into Amelia. Cool beans.

Richard Hull
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Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
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Jim Kovalchick
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Re: Local geographic gamma counting- how is your soil?

Post by Jim Kovalchick » Sat Sep 21, 2019 11:10 am

Hunter,
When checking the UVA research reactor site try sampling the soil in the pond. If you find anything it will be there.

Jim K

Hunter Long
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Re: Local geographic gamma counting- how is your soil?

Post by Hunter Long » Sat Sep 21, 2019 1:39 pm

Ok! Thanks for the tip. Why would that be the case though?

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Jim Kovalchick
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Re: Local geographic gamma counting- how is your soil?

Post by Jim Kovalchick » Sun Sep 22, 2019 2:46 am

Hunter,
The pond was used by the facility for routine releases. Very low activity but the facility operated for a few decades. The pond may have accumulated.
.
Point of trivia is that same pond provided water to the area for a couple hundred years.

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