Re: Simples.
"a lot of cyanide was being flushed down the drain."
We had a Belfast sink* (we were in Belfast) in the lab that persistently leaked. I had a few goes at trying to tighten up the fittings over the years. Eventually I realized that the hydrofluoric acid that had been tipped down it had eaten its way through the glaze.
*Note for colonials: made out of white glazed earthenware.
Biting the hand that feeds IT
