Is joint compound down drain w/septic a no-no?
I'm having some remodeling done and have a septic tank. The GC has been washing the joint compound off his tools and trough in my sink. I know of all the usual things I'm not supposed to put down the drain, but what about joint compound? Will it stay in the tank until it's pumped, or can it get into the drainfield? I want to say something to him ASAP if he needs to stop.