Michigan, California, Texas, Connecticut, Massachusettes, ... it is not that difficult. Brine discharge, and almost any High TDS water discharge in to the sewer system is banned in the San Bernardino and Riverside counties for all commercial applications as well as the counties of LA, Orange, San Diego, etc.. all have area specific bans depending on the waste treatment plants ability to treat the water and their outfall. Variances are allowed for businesses that can tie into the SARI line. I have worked with many businesses to determine the cost feasability of connecting into theis line, as well as brine concentration and transport to SARI line truck dump stations.
I am not understanding where you are going with this line of questioning
Oh, almost forgot, yes, many places have banned softener discharge into septic systems.
My original comment was that as an industry we need to promote efficiencies in all ways, this would go a long way to preventing, or postponing many of the bans that are in the works.
Hope this helps