Fairfield in Sinks after the fire

I went up to Fairfield Hill to explore after the fire. The rock seems sketch. Does anyone know how fire affects rock and/or bolts? I assume for the worse, but I'd be curious to know some science behind things. I'd guess things vary dependent on heat and length of burn. Hmm.

I've been checking it out quite a bit up there.

Not too many routes got toasted and they were ones that had trees near the base. Mainly caused a lot of spalding of the rock around the burned tree. You can see all the peeled rock flakes lying at the base and there are probably some less obvious loose flakes still on the wall. Hopefully they will peel off this winter.

The routes affected are: the 2 routes left of Blind, Physical Graffiti, possibly Yer Own Private Idaho, LL&L, Born X-Eyed (perhaps the worst effected), Alan Shepard Goes to Space, the 3 routes right of Shadowline, Only Pretty as You Feel, and a little on Hand on the Torch. The rest of the routes are still okay as far as I have done.

I went up there after the fire and bounce tested the first bolts on most of these routes. They held, but, I don't know. Especially the older Rawl three piece bolts (hex heads) may be compromised. I just don't know. I think the newer stainless steel bolts are probably okay but again, not totally sure. I may go up and replace the bolts on LL&L since it is somewhat popular and the bolts are pretty old Rawls.

Anyway, there were not that many routes badly effected by the burn, mainly the ones I mentioned. I'd stay off these until winter passes and hopefully the spalding will peel off this winter. I'd be real careful with it all.

I have an update on this.  After pulling a fair number of fire affected bolts at Fairfield 6 years post burn this is my findings about Bighorn Dolomite.

- The closer to the ground/fire the more rusty the non stainless hardware is.

- I personally saw several examples where the rock “dinner plated” at the same depth as the bolt, my theory is that the metal bolt takes the heat deeper into the rock to cause spaulding at that depth.  Even on what was likely a bomber bolt placement originally.

My conclusion- I do not trust the rock behind any burned bolt near a burned tree.   Stick clipping past is recommended.  Specifically for Fairfield I believe every burned route need to be re-cleaned (with crow bar if needed) as many of the good holds will be removed then after that has been done the route can be re-envisioned/graded/re bolted as a new route.  I have found that doing this has lead to better quality although more reach depended routes post fire.

The Morse-Bradys wrote:
- I personally saw several examples where the rock “dinner plated” at the same depth as the bolt, my theory is that the metal bolt takes the heat deeper into the rock to cause spaulding at that depth.  Even on what was likely a bomber bolt placement originally.

Interesting observation.  (I believe the word you're wanting is "spalling".)    

Could be both the bolt conducting heat into the rock and having a higher coefficient of expansion than the rock, creating pressure, and thus the dinner-plating.  

John Byrnes wrote: . last time I was there, Sinks was in Wyoming   

but if every car in Sinks is a  Subie with Greenie plates, every weekend, then all becomes one with the Borg-rado

Tim Lutz wrote:

but if every car in Sinks is a  Subie with Greenie plates, every weekend, then all becomes one with the Borg-rado

Don't tell that to the guys in the uniforms with the brown cars.