While you are at work, drinking water is being treated to make sure it is safe (Public Works), while the lab continuously tests the wastewater quality (Public Works) and the garbage is hauled to the landfill (Public Works).
(you; are; at work) (the lab; continuously tests; the wastewater quality) (the garbage; is hauled; to the landfill) (drinking water; is being treated; to make sure it is safe) (it; is; safe)
you the lab the garbage drinking water it
are continuously tests is hauled is being treated is
at work
the wastewater quality
to the landfill
to make sure it is safe
safe