Over time I’ve had a couple different chimney sweeps install (and then reinstall) my wood insert. First one was a hack job and the second one corrected those issues. Currently, there is a fair amount of masonry debris remaining on the smoke shelf from removal of firebrick and masonry near rear damper along with small bits and pieces of old clay liner that was broken out. Basically It’s a mix of different types of masonry broken up together in a dusty pile up there on the smoke shelf. Would have been nice for installer to have removed but didn’t happen. Masonry chimney built in 1977, and I’m not sure if any of this masonry could have contained asbestos. Forgive me if this is a silly this is silly question altogether, but I’m wondering if I should remove this debris or just leave as is. Access is a bit difficult with insert in place and I anticipate that removing it will be challenging and a bit dusty on its own. Been running the insert line thus for a few years but just thinking of it now. Thanks.