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If you have been involved in lab renovations where bench tops were to be re-used and 'spruced up' a bit perhaps you can provide some guidance about some we have that appear to have suffered perhaps heat damage as well as chemical stains. They belong to a lab used by a faculty member of 35+ years' tenure; we aren't sure whether to totally resurface them, would it help to sand the tops down, etc. These counters are likely original to the building (mid-1960's), and were originally a charcoal-ish black....
They have been tested for asbestos and do not contain it; counters have been confirmed to be stone, with 25% wollastonite so perhaps are some sort of manufactured stone?
All horizontal surfaces will be cleaned professionally for chemical/biological residue by a national company specializing in these services before any construction workers enter; contractors will follow OSHA and state construction safety requirements. We are aware there may be 'surprises' uncovered during construction (whether these are refinished or not) and will test accordingly...
If photos would help, I'm more than happy to provide them if you send me your email....
Many thanks to everyone-
Margaret A. Rakas, Ph.D.
Lab Safety & Compliance Director
Clark Science Center