"Hazardous waste facilities," as used in this article, are facilities
to treat, store, process, alter or dispose of waste that may cause,
or significantly contribute to, an increase in mortality or serious
illness in humans or animals or pose a substantial present or potential
hazard to human or animal health or the environment when stored.
Nothing in this article shall be deemed to prohibit the on-site
processing of waste resulting from otherwise lawful and permitted
on-site manufacturing or other lawful activity.