There has always been some speculation as to the amount of uranium hauled by the RGS, but there is likely little hard information that is easily available.
Most of the uranium mines were located west of Placerville, in the Uravan Mineral Belt, and not readily accessible to the RGS [or D&RGW]. The vanadium deposits in the Placerville area [which supplied the Primos Chemical Company mill [Newmire/Vanadium] and others] had very little uranium associated with it, so these ores were not really considered to be viable uranium resources by the Union Mines Development [Union Carbon and Carbide and the Manhattan Engineer District company that was charged with managing uranium resources in the US during the War].
Ore from the Uravan Mineral Belt deposits [which are vanadium deposits with strong uranium mineralization as well] was hauled to the mills at Vancoram [just west of Naturita], Slick Rock, Gateway and Uravan [Joe Jr. mill] where it was processed and uranium ["yellowcake"] and vanadium ["red cake"] concentrates were recovered. I have yet to find how it was packaged, but I suspect that it was in barrels [today it is packaged in 55 gallon drums] and transported by truck. The yellowcake would have then been transported to an enrichment facility, which I think may have been in Pennsylvania.
There is another myth that yellowcake was transported on the Chili Line for delivery to Los Alamos, but there is no evidence to support that.
In any case the RGS and D&RGW would have perhaps hauled only some yellowcake, and not likely sandstone ores. With that in mind I wonder about the old ASARCO mill across the river from the Durango yard, which was acquired by the Vanadium Corporation of America and converted to a uranium processing facility under contract to the US Atomic Energy Commission. If I remember correctly, this mill was not converted to uranium/vanadium processing until late in the 1940's, just before the demise of the RGS operations.
There is a myth that the uranium for the bombs built during the Second World War came from western Colorado, but that is not true - the uranium came from Canada and the Belgian Congo.
I have spent a portion of my career as a uranium geologist, and have worked in western Colorado, in the Uravan area. I am also quite interested in the history of the early uranium industry in the region. While I have quite a lot of old data about the industry I have never run across any data on a narrow gauge railroad connection, other than the article "Atomic Narrow Gauge", which is a well done article.
Regards,
TED
u3o8geo
