Just this minute got back from the site,
Tried to clear the roots away but they proved tougher to shift than I imagined. Took a pic of the base again with the edge cleared. Gloves for scale. Couldnt find any conduit on this search Resmoroh.
What I do keep failing to appreciate, is that the wood that is there now, has grown further out by about 30 feet in places. and makes it difficult for me to get my bearing on what was where and when! Something NP tells us often is not to rely on the plans for total accuracy.
*I have edited this post as I believed it was the streamer mast base. After consulting with JimC who pointed out my 245 and 243's were round the wrong way! The streamer mast was the other side of the control tower. The only buildings on the plan in the same location to this base were a Gas Equipment store and a Battery Charging Room. This base remains a mystery*.
Thanks to everyone for their input into this thread.