This note was posted to the Titanium Bolting FB Group 21 January 2020
Bit of a back story here…. When I first visited Railay, some 12 years ago, I had heard stories about perfectly good-looking SS bolts snapping under body-weight, but being ever the scientific skeptic, I thought I’ll believe that when I see it for myself. I was still to learn that lack of chalk was a bad sign when it comes to choosing routes.
So it happens that I come to the last bolt before the anchors on a nice climb in the centre of Castle Wall when I am forced to believe what I see. A Fixe hanger is corroded and split in spectacular fashion. Now here was something different indeed. It only took a second or so for my mind to process the fact that the same process might be operating for the 6 bolts below me, and that back-climbing with care would be a great life choice.
So started my interest in SCC and the security of climbing anchors, and the fact I spend more time messing around doing chemistry rather than climbing.
I took 10cm x 10cm wash samples from two points at the base of this climb and recorded high sulphate levels. Well how about that?
I also checked at a couple of points elsewhere on the wall and found lower levels. I also measured a surface not physically connected to the main wall and got only a trace of sulphate.
My current theory is that whilst elemental sulphur is probably well distributed by the coarse aerosol, not all points on the wall are amenable to the needs of happy little sulphur-oxidising bacteria. Perhaps their ideal location is the soil at the very cliff-top, and run-off from here is required to generate a sulphate streak down the wall? Every measurement generates more questions than it answers.
So what happens if we step back through the jungle 30m or so to Kochel Rock? A trace of sulphate no more.
Move a further 20m back to Duncan’s Boot? A trace of sulphate.
Head up to Hidden World, maybe 100m from sea, and we find no trace of sulphate.
I don’t have a clear picture of the corrosion rate of these more sheltered crags, but looking at 20 year old SS staples on Red Dwarf and Tom’s Pitch I couldn’t see any indicators of interior corrosion at the glue line. I suspect this crag is benign.