If my memory serves me....
they were placed there many years ago as net stakes. I recall losing two reef runners a few years back just South of Hunters Point. Seeing that one of the RR's was attached to some leadcore, we stopped the boat, picked up what rods weren't hung up and headed back to retrieve whatever we could. You could clearly see the top of the pole/stake as it was no more than 15' below the surface of the water.
Please correct me if I am wrong on this as I heard it second hand and, like I said, it was a few years ago and my memory might not serve me as well as I think. Tight Lines