What legal recourse do I have if contamination is migrating onto my property from a neighbouring site in Ontario?

If contamination is genuinely migrating onto your land from a neighbouring property, you generally have more than one avenue available. Ontario's environmental protection framework allows the ministry to investigate and, where appropriate, issue an order against the party actually responsible for the source of contamination, which can include a neighbouring owner whose site is the origin, separate from any obligation you have regarding your own land. You can typically report a suspected contamination source to the ministry to trigger that kind of investigation.

Separately, you may also have a civil claim against the neighbouring owner, potentially framed around nuisance or negligence, seeking damages or an order requiring them to stop the ongoing migration and address the contamination at its source. Practically, the first step is usually getting solid environmental evidence, through testing on your own property and, where possible, information about the neighbouring site's history, since both a ministry complaint and a civil claim benefit from documented, expert-supported evidence of the migration and its source. Given the overlap between regulatory and civil routes, getting legal advice early helps determine which combination of remedies fits your specific situation.