I’m an environmental scientist/consultant (for 32 years!). Yes, report pollution to your state or local environmental regulatory authority or fire department. There are usually hotlines to call. Examples would be evidence of a spill of hazardous material (e.g. weird-colored or chemical-smelling liquid on the ground or surface water) or abandoned containers and drums, especially if they’re leaking.
Most contaminated sites are well known to regulatory agencies. You can find them on their websites. I work mainly on the West Coast. Here are some sources to find contaminated or otherwise regulated sites:
Washington: https://ecology.wa.gov/Regulations-Permits/Guidance-technical-assistance/Facility-Site-database
Oregon: https://www.oregon.gov/deq/Hazards-and-Cleanup/env-cleanup/Pages/ecsi.aspx
California (GeoTracker and Envirostor):
https://geotracker.waterboards.ca.gov/
https://www.envirostor.dtsc.ca.gov/public/