During construction years ago, workers hid in tiny alcoves as they blasted out the tunnel now leading to the pump storage plant built into the bowels of Raccoon Mountain.
On Monday, Ryan Fruth, the plant’s maintenance manager, pointed out those small nooks still carved into the walls as a shuttle transported visitors through the long passageway leading to the facility under Nickajack Lake in Marion County. In some parts of the station, the smell of sulfur naturally exudes from the stone, and it’s possible to spot small stalactites dangling from the ceiling.
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Inside, the Tennessee Valley Authority operates a massive hydroelectric battery capable of generating about 1,700 megawatts of electricity – enough energy to power nearly 1 million homes. The tops of four generators sit in a cavernous underground room near the entryway overlooked by a series of offices.

