I've long wondered if near this spot was a significant rock slide that occurred sometime between 1911 and 1924. This seems to be the beginning of the remaining mile of track that went past Alpine Tunnel station and into the tunnel itself that was not pulled by the scrapper.
Mac Poor in DSP&P quotes a Gilbert A. Lathrop who visited the pass in 1936 as writing, “Although the pike closed down about 30 years ago, a locomotive could still run on the track to a point where a rubble of massive granite chunks came down the mountain just east of the Palisades, blocked the line and kept some scrap iron salesmen from completing their job of total demolishment.”
A curious story came to light on the DSP&P forum a few years ago. A poster said that he came across the following in a source he can no longer recall, but possibly a CRRM Annual. He read that the scrapper, having run into the large pile of rubble, attempted to slide the rails straight down Tunnel Gulch to the lower grade and pick them up there. However, “The rails got away from them down the steep Gulch and almost killed the men and the horse. They decided that it was too dangerous and that the value of the rails not worth the extreme risk, so they abandoned the idea.”