I no longer use resin at the moment, just use the RO to bring the water tds down...
But when I have used resin I just scatter it on the lawn or flower beds, as Ian Lancaster said, it almost certainly will do more good than harm.....However!!
To comply with regulations it is supposed to be disposed of correctly...
Did you also know that the trad window cleaner also has to dispose of the water in his bucket in accordance with the regulations concerning the disposal of waste?
You are NOT ALLOWED to empty your bucket of dirty water down the drain or the gutters in the road.
It pathetic isn't it?
A few years back, my dad had a contractor come in to replace a broken pane of glass in a factory his firm had built...a single, small pane of glass...
He noticed someone watching him, thought nothing of it, but this person then followed him off site all the way back to his depot and watched him throw the broken pane of glass into his skip, or whatever container he used for this kind of thing.
The guy get gs out of his car and gives him a thorough warning with threats of prosecution...
He was told he should have arranged for a skip to have been on site to have safely disposed of the glass and he should not have removed the hazardous waste off site, he was a glazier and did this all day every day, but can you imagine the cost involved if he followed this dozy pillocks advice?
It was only a georgian pane of glass, oh and as it was first floor he should also have arranged for scaffolding or the like to have been in place.
Mind how you go
Ian