More "Booms" in an area when locals know of tunnels and underground bunkers. Think Greenbrier exclusive Hotel and Conference center kind of bunker.
Berkeley County Sheriff Keller says emergency calls ranged from as far as the Hedgesville West Virginia to Maryland. Residents in the area report hearing loud explosions that shake their homes several times over the span of a few months. – LocalDVM TV station
Mysterious booms and rumblings, and strange sounds baffle residents across the world, but nobody knows why - Strange Sounds
http://strangesounds.org/2019/05/mystery-booms-rumblings-strange-sounds-video-news.html
Mysterious explosions concern residents in Berkeley County, West Virginia – Earth Changes – Sott.net
https://www.sott.net/article/412224-Mysterious-explosions-concern-residents-in-Berkeley-County-West-Virginia