Quirke Lake

[6] Summer 1993 sampling found the pH level of 6.3, marginally outside Ontario's provincial lower limit of pH6.5 set for aquatic life and drinking water.

[3] The study also found that, following the earlier extirpation, reintroduced trout were naturally reproducing at a slightly slower rate than nearby Elliot and Dunlop Lakes.

[2] In 1996, the Canadian Nuclear Safety Commission reported on consideration that was being given to disposing of uranium mining tailings into the Quirke Lake, but also noted that to do so would be perceived as controversial.

In 2011, a Denison Mines internal report noted that uranium levels still regularly exceeded Ontario's 1994 provincial water quality objective at the inlet to the lake.

[8] The same report noted that calculated radiation doses to humans were 0.288 mSv/a (mill-Sieverts per annum) and described the lake as an "area of concern":[8]"In general, water quality is improving and environmental impacts, such as decreased benthic community taxonomic richness and abundance have reduced in magnitude and spatial extent such that only waterbodies immediately downstream of Quirke, Denison, Panel and Stanleigh are measurably impacted.