The range of 60-70 decibels sound pressure level is about as loud as normal conversation in 1 meter distance.
Flammable, Radioactive Sinkholes. Lesser known in the mainstream media, however, is frackingâs link to massive sinkholes appearing overnight and leaking radiation across the nation.
Sinkhole subsidence is common in areas overlying shallow room-and-pillar mines. Sinkholes occur from the collapse of the mine roof into a mine opening, resulting in caving of the overlying strata and an abrupt depression in the ground surface.