toxic dumpsite vs garbage dump

toxic dumpsite and garbage dump both are nouns.

Word	Noun	Adjective	Verb	Adverb
toxic dumpsite	Yes	No	No	No
garbage dump	Yes	No	No	No

As nouns, garbage dump is a hypernym of toxic dumpsite; that is, garbage dump is a word with a broader meaning than toxic dumpsite:

toxic dumpsite: a location where toxic wastes can be or have been disposed of (often illegally)
garbage dump: a piece of land where waste materials are dumped

Other hypernyms of toxic dumpsite include dump, dumpsite, rubbish dump, trash dump, waste-yard, wasteyard.

toxic dumpsite (noun)	garbage dump (noun)
a location where toxic wastes can be or have been disposed of (often illegally)	a piece of land where waste materials are dumped