Solid or viscous substances which may cause obstruction to the
flow in a sewer or otherwise interfere with the operation of the wastewater
treatment facilities. Unless explicitly allowable by a written permit,
such substances include, but are not limited to, grease, garbage with
particles greater than one-half inch in any dimension, feminine hygiene
products, diapers, toilet wipes, 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,
waste paper, wood, plastics, gas, tar asphalt residues, residues from
refining or processing fuel or lubricating oil, mud, or glass or stone
grinding or polishing wastes.