Homebrew PCBs

I am planning to follow one of recipes for making copper etchant from hydrochloric acid,and was wondering how I should dispose of the used etchant?  I know that there are methods for refreshing the etchant for reuse, but I am still at the process debugging stage and storing the used etchant for long periods is not feasible.  The formula I was going to use is the one posted in this groups Files directory.