Radioactive waste leaking into Lake Ontario

According to the report, Port Granby: leaking radioactive hazardous waste site, by the NGO, Lake Ontario Keeper, in the past, researchers have found that as much as 10% of groundwater, and 25% of surface runoff leave the site where the waste is buried untreated and flows into the lake. The remainder of the water is collected in ponds before being treated to remove radium and arsenic and to have the pH adjusted, and then the water is released into the lake. However, the report notes that during the winter/spring period of 1993, there were three overflow events with further overflows over a two day period in 1994.

According to the 1993 annual report of the Atomic Energy Control Board (AECB), during the summer of the previous year there had been four monthly periods during which the discharge exceeded the licence limit for radium. During 1994, researchers also found that discharges into the lake exceeded the guidelines for monthly average arsenic concentrations eleven times and for ammonia once. Research also revealed elevated arsenic levels in the soil below the discharge point, and elevated levels of uranium in soils and effluent escaping from the facility. During two separate sets of laboratory tests in 2000, water fleas were placed in samples of the treated effluent, one of which killed 63% of the flees in 48 hours, and the other killed 97% over the same time period.

Despite the apparent free-rein that has been allowed to this facility, the AECB has stressed concern about its operation, calling for its decommissioning in 1980 because of concerns regarding the stability of the bluffs and slopes. However, this was delayed in order to allow those involved to find alternative long-term storage facilities for the wastes, although no new waste has been admitted since 1988. Such a site was not found, and so the site is now being assessed for redesign as a permanent facility.

Officials from the Canadian environment ministry were unavailable for comment on the matter.