We're talking about the water table, not the river.
They do a lot of studies at Waterloo University on the compounds present in the water table around the oil sands. This isn't my field. Consequently, I don't have a lot of information on the subject. However, the toxic compound that I know little about concerns the naphthenic acids.
I know that the concentrations of naphthenic acids are much higher in the tailings ponds than in the water table. The studies being conducted at Waterloo University and the University of Alberta are attempting to establish whether there is a way of distinguishing the naphthenic acids naturally present from those present as a result of the extraction of bitumen. They're currently trying to determine whether those compounds come from bitumen that is naturally present or are there as a result of bitumen extraction and, consequently, whether it comes from the tailings ponds.
I don't know the current levels. Also, all the data from the Regional Aquatic Monitoring Program, which of course studies the Athabasca River, not only the water tables, have shown that there weren't a lot of naphthenic acids in the Athabasca River. I suppose the same is true of the water tables, but I don't have the data with me.