I visited the site of the Ruined Castle Shale Mines a few weeks ago with a group of 10 bushwalkers, with the aim of having a good search around to locate previously unrecorded items.
We took along a metal detector which found an underground 2" waterpipe, and some rail dogs.
We found and recorded three mine skips with wheel sets, a ropeway ropesaddle ( photo attached- Google won't let me attach the photo as it is bigger than 2000 pixels x 2000 pixels, what photo isn't??!! ) which can be seen on the left hand end of tower 46 in the other photograph, and a ropeway bucket and relocated the end of the inbound rope - photo attached.
This visit I took along my Garmin GPS, so everything is now logged.
But the semicircular trench that I recorded on my last visit 25 years ago was nowhere to be found. I sketched the trench then as being 2 M deep 1.5M wide and about 20 M long. The trench originally was for the loading of the ropeway buckets and it had the bucket transport rail suspended along its length from timbers laid across the top spaced at about 2M .
Is it possible that a trench very obvious in 1977, and then 88 years old, could have filled itself in in the subsequent 25 years? Seems unlikely to me. But I'm seeking advice. There has not been any significant bushfire activity in the area during that period. The area is marginal temperate rainforest.
The obvious solution is that my memory is lousy, and that my sketches are rubbish. Also a possibility!