Chili John has his facts correct. In addition, there are photographs and a movie in the Los Alamos Laboratory archives of the house at Otowi station during the first years of the Laboratory. There are no tracks in the photographs and the railroad bridge is not visible. Only the single lane highway bridge is present in these pictures. The old highway bridge has been restored and is still in place across the Rio Grande river. There is quite a bit of photographic documentation on this site during the war. There is a good book titled "The House at Otowi Crossing" that documents the activities around Los Alamos during the 1943 and 1944 time frame.
Over the past 10 years the Laboratory has done a lot of research on the early days to clean up environmental legacy from the Manhatten project. In all the documentation there is no evidence to support the thought that the D&RGW left any part of the Chili Line in place after abandonment in 1941.
My wife and I detoured to Espanola on our way home from Santa Fe this afternoon to try and find the site of the D&RGW station in Espanola. The grade from Espanola and at Otowi crossing is still very visible today if you know where to look. Given the grade that remains at Otowi today there never was much traffic from the Chili Line off loaded at this station.
It is fun to speculate what might have happened if the D&RGW had not pulled up the tracks of the Chili Line until after the begining of the Manhatten project at Los Alamos.
Scott Gibbs
Associate Director for Security and Facility Operations
Los Alamos National Laboratory