Solid or viscous substances which may cause obstruction of the flow
in a sewer or other interference with the operation of the sewer system,
such as but not limited to animal guts or tissues, paunch manure,
bones, hair, hides or fleshings, entrails, whole blood, feathers,
ashes, cinders, sand, spent lime, stone or marble dust, metal, glass,
straw, shavings, grass clippings, rags, spent grains, spent hops,
wastepaper, wood, plastics, gas, tar, asphalt residues, residues from
refining or processing of fuel or lubricating oil, mud or glass grinding
or polishing wastes.