I'm not sure where I got this map from but my first guess is Dick Bell. It will give you a general idea of location...
These are scans of slides I took in 1982 of the La Plata Coal Mine. Locals also called it the "Spring Mine" as a spring ran out of the portal. Facing NE overlooking the loading area...
Standing in the loading yards looking NW...
Although not much is known about the La Plata Coal & Iron Co. railroad operation, there is excellent information on this short lived branch by
W. George Cook in Sundance's
RGS Story Vol. IX. D&RG engine #23 was bought by the company that built this line and then sold back to the D&RG. I have traced this locomotive until it disappeared. It became TAS #2 and later was used on the Pagosa lumber lines. I believed that it burned up in a engine house fire in Edith, Colorado...