I usually have about 2 to 3 gallons of the foamy sanitizer left in my 5 gallon bucket I use for cleaning tools, tubes and my carboy for every brew session but I have been dumping the leftover down an abandoned groundhog hole at the far side of the property as I do not want it impacting my septic tank's balance. The reason I ask is somewhat looking for an acceptable and smart reuse of a brewing "by product" as I wear my well worn cheap bastard hat, but I also live on a well and septic. I am very watchful of both systems as repairs are costly and the impact of any failure is really an upset to daily life! So all you guys on town sewers and such, are most likely dumping it down the drain but what about other users out there? Are there other uses or is it simply a disposable necessity? The folks at 5 Star say it's fine in septic systems but to dilute it heavily so that means more water use and I hate to over use water!