If your organisation is registered with the EPA Litter and Dumping Management System go to https://ladms.epa.tas.gov.au/ to report dumping activity.
If you have not yet registered to access this portal go to https://epa.tas.gov.au/about-the-epa/policy-legislation-cooperative-arrangements/cooperative-arrangements/report-rubbish-and-the-litter-and-dumping-management-system to download a registration form.