Can't we use the exceedance of ozone at ground level to fill the hole in the ozone layer?
Ozone is a very unstable and reactive compound. For example, ozone can't be stored in bottles because it would immediately oxidate the walls of the bottle. As such, a first problem rises: how would you store it? In addition, during an period with ozone exceedances (ozone smog episode), ozone levels are not too high during the whole day. Ozone concentrations will increase during daytime, with a peak in the late afternoon, but will decline sharply by night (to almost 0).
When considering the total amount of ozone, the ozone in the lower atlmosphere is only a fraction of the amount in the ozone layer (less than 10%). Even if it would be technically possible (which is not the case), the transport of ozone to the ozone layer would be nothing but a drop in the ocean. The formation of ozone in the ozone layer is a process of formation and decomposition. On a daily basis, millions of tonnes of ozone are formed in the stratosphere (where the ozone layer is formed).
Preventing further thinning of the ozone layer can thus only be achieved by regulating the use of ozone-depleting compounds.