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.
In addition, cover-collapse sinkholes have formed along roads or other areas where water is repeatedly released onto the ground, washing soil into underlying bedrock cavities and creating soil caves that can collapse. Salt mining has also created sinkholes. In 2008 two large sinkholes formed in southeastern New Mexico when cavities produced by brine well operationsâa process that injects fresh water into salt beds to make brine for use as drilling fluid in oil wellsâabruptly collapsed.