In a puddle in one of the handholds in the climb up from Basecamp chamber is a population of small red worms
about 1.5 - 2 cm long and maybe 1 mm wide.
number, nor sure as they're small ... over 50 ?
I didn't have a camera sorry.

Is anyone interested ?

Tubiflex worms are red and live in water with sediment like this and are about the size you describe. They can tolerate some quite polluted water - I assumed they will have washed in or something and are living in the sediment.

https://en.wikipedia.org/wiki/Tubifex_tubifex

looks like a match.