Assertion: septic tank | /r/CapableOf | accumulate scum
Facets:
Source sentences:
text: If the septic tanks accumulate too much sludge and scum, the effective volume of the tank is reduced which in turn reduces the time for separation to take place.
text: A septic tank accumulates solids (sludge) and scum which should be pumped out at least every three to five years.