Very interesting. Maine also has a significant transmitter array in Cutler with 30 or so antennas around 900 ft tall apiece. https://en.wikipedia.org/wiki/VLF_Transmitter_Cutler

I wonder what it's like to try to pull a signal up there.

Your comment brings up memories of Lighthouse Beach in Chatham, which has a ton of warnings about Great White Sharks due to the prevalence of seals in the waters. Beautiful place. If the sharks don't get you the radio frequencies will I guess.