Well my holiday in Hayle came and went much too quickly, apologies for not catching up with all those who offered to meet up, Mrs T's cancer recovery and my recent medical issues meant many of our plans didn't quite come to fruition.
I did spot a level coming out onto the beach near where we were staying at Riviera Towans however and poked my nose in whilst on a stroll. I believe this was the drainage adit of Wheal Lucy? One afternoon when Mrs T was resting I did venture forth agsain armed with a torch to see how far it went. It deteriorated to a rather low crawl fairly quickly due to washed in beach shingle. After about 20' I noticed a seriously unpleasant sewage smell, since it was far to tight to turn around I backed out then returned to the entrance where I noticed the massive human turd I had crawled through on my way in and had been smearing up the sleeve of my jumper as I crawled.
I washed most off in the sea but the pointed looks and raised eyebrows on my return discouraged any further exploration. Fortunately there was a washing machine where we were staying.
The point being I never reached a conclusion to the level - anyone been up in more sanitary conditions?