Thick mud or sediment (6)
I believe the answer is:
sludge
(Other definitions for sludge that I've seen before include "Gloop, gunk, muck" , "Thick, soft, wet mud" , "Thick greasy mud" , "Melting snow" , "'Muck, slime (6)'" .)
I believe the answer is:
sludge
(Other definitions for sludge that I've seen before include "Gloop, gunk, muck" , "Thick, soft, wet mud" , "Thick greasy mud" , "Melting snow" , "'Muck, slime (6)'" .)