I spotted this small, reflective green target attached (by what looks a bit like a splodge of chewing gum!) to a lamp post at Stapleton Road station a few days ago. Does anyone know what it's for? I'm guessing some sort of surveying feature?
It is a standard / basic target used for surveying. It is more than likely being used to check for movement from a fixed datum point..
We sometimes use them on weak embankments to check track movement but you can easily fix them to most things.