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The Most Radioactive Town in America

A cache by DresselDragons Send Message to Owner Message this owner
Hidden : 12/10/2006
1 out of 5
1.5 out of 5

Size: Size: other (other)

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Geocache Description:

The Standard Chemical Company operated a Radium refining mill from 1911 to 1922 in Canonsburg, PA. From 1930 to 1942, the company purified Uranium ore. The mill was in Pennsylvania in stead of Colorado (which would have been closer to the mines that produced the carbonite) because the processing of the ore required huge quantities of chemicals; these chemicals were available in Pennsylvania. This mineral resembles yellow sandstone; the yellow color caused by uranium. The ore contained such a small amount of radium that took up to 500 tons of ore to produce a single gram of radium. Up until 1921, a total of 120 grams of radium (valued at $14,400,000) covered the world's supply of this precious mineral; and of this amount the Standard Chemical Company had produced 72 grams, valued at $8,640,000. The Canonsburg plant produced more radium in a year than all of the rest of the radium plants in the world combined.


In 1921 Marie Curie visited the United States. She started her tour with a reception at the White House, where President Harding presented her with a gift of a gram of radium produced by the Standard Chemical Company. She was also given an honorary degree by the University of Pittsburgh. On May 27, 1921 Marie Curie visited the Standard Chemical Company works.

In this photograph from the archives of the Historical Society of Western Pennsylvania, taken during her visit to the Canonsburg plant, an Marie Curie converses with Louis Vogt, Canonsburg plant manager on the left, and James Gray, company president.

From 1942 to 1957, Vitro Manufacturing Company refined uranium and other rare metals on-site. The government bought this uranium from Vitro and used it in the Manhattan Project. Waste from site operations accumulated during the site’s long history. Originally, the waste was left uncovered. It contaminated the group, and caused cancer for most residents on a street down-wind of it. After the closure of Vitro, the site was used by the U.S. Atomic Energy Commission, and, later the site was then used by a pottery plant; Canonsburg pottery can be detected by Geiger counter.

The Canonsburg mill site was designated in the 1978 Uranium Mill Tailings Radiation Control Act as eligible for federal funds for clean up. It was the only uranium mill east of the Mississippi River to receive funds. Under a $48 million cleanup, the mill site and 163 vicinity properties in Canonsburg were remediated. Residual radioactivity was consolidated into a covered, clay-lined cell at the Canonsburg mill site that is fenced and posted. Erosion control measures were taken along the adjacent Chartiers Creek, and a groundwater and surface water sampling program was initiated.

This EarthCache will take you to the original site of the Standard Chemical Company, and the current remediated “cell”. PLEASE OBEY ALL SIGNS, and be careful walking along Strabane Avenue. You do not need to cross the fence or trespass to gather the required information to log this earthcache. A granite site marker identifying the Canonsburg site, located on the other side of the fence, is visible from Strabane Avenue...the coords will take you to the spot where you can see the marker. There is grass surrounding the marker, but it is still visible. IF it gets too high or the marker is snow covered, and you cannot gather the required information at the site, a little internet research will help you fill in the blanks. To Log This Cache: Please obtain the following information from the site marker: the date of closure (ie: when they closed the cell), the wet tonnage of tailings in the disposal area, and the curies of radioactivity. Additionally, you MUST locate one of the monitoring wells (see picture) installed on the adjacent, vacant lot across the street from the cell. You do not have to actually go to the well; you might be able to see one from the sidewalk. Think about why they installed these wells here, and include your theory with the marker information in an email to the cache owner to get credit for this EarthCache. Please DO NOT post pictures of the granite marker, but feel free to post any others. We entered a couple of other waypoints, to give you different views of the cell.


Additional Hints (Decrypt)

Gur jryyf ner pbirerq ol zrgny ybpxrq pnfvatf...gurl fgvpx hc gueh gur tenff. Gb svther bhg jul gurl jrer cynprq gurer, ybbx ng gur gbcbtencul.

Decryption Key


(letter above equals below, and vice versa)

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