I heard through the grapevine that contaminants were found during the testing back in August. What they were I was not told. The source of the contaminants was unknown. An article in the Ottawa Daily Times recently suggested that a slag pile and some ponds that were contaminated with various acids, and once owned by a defunct fertilizer plant, could leach or spill into the river if the water were to rise that high. It was suggested that if this were to happen, it could cause a fish kill as far as ten miles down stream. I don't know if there is any connection.
As far as I know , the last reported fish kill on the lower stretch of river was back in 1988. It was during a low water period and affected the the river from the mouth to about a mile upstream. I witnessed that mess as it was happening. Heavy metals were the killers, dumped by a company not from the area. It killed thousands of fish. Most were rough fish, but I saw some huge catfish, smallies, walleye, and a 17 pound muskie that were killed. Very sad and in a few days very smelly.