Where was the waste and garbage dumped from the town and factory in the lorax?

River

Explanation:

All the waste generating from increased industrial production or increased population  in the town was dumped into the river stream.

This open dumping into the river not only contaminated the water body but also caused nuisance as it led to arise of infection and diseases.

Due to all such incidences, the town soon converted into ghost town and it soon became inhabitable.

answer; i believe that the correct answer is (lung);

"a.) well–developed vascular system."