You "should" be able to find your well record here:
https://www.ontario.ca/environment-a...p-well-records. That is if a well record was submitted, sometimes especially with older wells, the drillers didn't exactly follow the rules.
An ecoli problem didn't come from a cattle farm a mile away, you need to look local and you should have your well and casing inspected, it's likely that there is something wrong with the well seal. Do you have a dog? Is it peeing and pooing around the well head? I've seen dogs chained to a well head, and then they wonder why they have a positive test result. Is there 40 cm minimum of stickup on the casing? Is the ground mounded away from the well head to prevent water pooling around the casing? How far is it from your tile bed? Under the wells Regulation, you are responsible for the upkeep and maintenance of the well to ensure it meets the standards and is safe.