Tidbits for those who don't know Cameron Park:
1. RWY 31 (crash runway) has a significant upslode beyond the runway which isn't totally obvious as to its extent/height when standing on the ruwnay. The whole world slopes up in that direction with mountains on either side adding to the visual illusion that the world is flatter than it is.
2. RWY 13 (opposite direction) appears to have a large hill blocking the departure path. Confirming this initial impression, the RWY 31 threshold is significantly displaced due to the large hill blocking the approach path to RWY 31. What isn't obvious when standing on the runway is that a slight deviation right (i.e. ~ 30 degree turn) when departing RWY 13 takes one around the hill via a very flat area/golf course into a region with no significant obstructions for several miles and, in fact, with another slight turn enters a downhill sled run to the Sacramento valley along the US 50 corridor.
IOW, the pilot may have opted for a tail wind thinking RWY 31 offered the best restricted performance departure route based on visual impressions from the runway, but which is unfortunately not true.
