These rocks come from the deposits of ancient seas. Mountains and glaciated land do not have these ancient deposits. So most of the acid rain damage has been done in mountainous areas and in Canada which has a thin soil layer from the removal of rocks by the glaciers. Ozone Thinning . While ozone is irritating to us on the earth, it is a useful chemical in the high atmosphere.
Ozone blocks out a great deal of ultraviolet and higher energy rays from the sun.
In this way it protects the earth from sun rays that are destructive to organic molecules like chlorophyll and those in human skin. Without this protection from the sun, we would stress plants more and cause more skin cancers. They are useful because they are very stable, Some turn into gasses readily as the propellants and refrigerants and these then are released into the atmosphere. Most chemicals get trapped by moisture in the atmosphere and are carried back to earth. The CFC's are not water soluble and spread throughout the atmosphere.