I don't know the deepest mine in the US but Resolution Copper Mining's #10 shaft in Superior, AZ is more than 6000ft deep
The superlative form of the word "deep" is "deepest".
The deepest ocean is 36,200ft deep
The Enterprise mine, a copper ore mine located at Mt Isa Mines, is currently Australia's deepest mine. Its shaft is 1,900m deep.
The Pacific Ocean has the deepest point in the Challanger Deep.
The merced river is about 5 ft deep at its deepest point.
Pretty Deep.
23cm deep
That is the correct spelling of "deepest" (most deep, or innermost).
The South Pacific Ocean is 35,797 feet deep at it's deepest point. This means that the deepest point is 10,911 meters deep.
Not that deep 2 to 3 centimetre
8 inches