I'm not sure where you can find general information about the environmental risks for each residential area, I suppose the info would be available in Ottawa City Hall.
However I've JUST received a letter from City of Ottawa, precisely stating that there is no environmental impacts associated with the former Township of March Landfill. Closed since 1973, the Landfill is located about 250 meters west of the intersection of Klondike Road and 2nd Line Road.
There is a monitoring program that continues to monitor the quality of private well, groundwater and surface water in this area. For more information on the former Township of March Landfill, contact Gordon MacNair at 580-2424 x21217.