On the other hand,the soil quality guidelines put forward by the Canadian Council of Ministers of the Environment, has set the allowable limits for heavy metal contamination to range from 1.4 - 10.0 mg/kg (Cd), 70.0-140.0 mg/kg (Pb), 200.0 - 360.0 mg/kg (Zn) and 63.0 - 91.0 mg/kg (Cu) for both agricultural and urban residential soils (CCME, 1999).
CCME - Canadian Council of Ministers of the Environment (1999).Canadian soil quality guidelines for the protection of environmentaland human health: Canadian environmental quality guidelines.
Canadian soil quality guidelines
for contaminated soil Metal Unit Critical Soil Concentration Cadmium ppm 3-8 Cobalt ppm 25-50 Chromium ppm 75-100 Copper ppm 60-125 Manganese ppm 1500-3000 Nickel ppm 100 Lead ppm 100-400 Zinc ppm 70-400 Iron (*) ppm 157,200 (20000mg/kg) Sources: CCME 2006.
Recommended Canadian Soil Quality Guidelines
for the Protection of Environmental and Human Health.
CCME's Soil Quality Guidelines Task Group is leading the review.
In December 2005, the Soil Quality Guidelines Task Group posted a draft revised NCS on CCME's Web site for public review and comment.
Our material is only applicable by meeting soil quality guidelines
for heavy metal concentrations in soils (Table 1).
The soil results were also compared with typical background urban concentrations in Canada and the Canadian Council of Ministers of the Environment (CCME 1997) soil quality guidelines for arsenic (12 ppm), lead (140 ppm), and PAHs.
The GM of benzo[k]fluoranthene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene (BaP) are above the Canadian soil quality guidelines (CCME 2002) in communities adjacent to the tar ponds.
Soil quality guidelines
suggested by Cornell faculty include maximum soil concentrations basing the amount of sludge to be applied over time on the level of contaminants in the sludge.
Chrome, Cu, Pb, and Zn concentrations were frequently above ANZECC/NHMRC (1992) residential soil quality guidelines
. Maximum metal concentrations were not adjacent to the road, as may be expected, but 30-50 m from the road, probably due to the constant, high velocity wind generated by vehicles on the road and flushing from pavement run off into adjacent park soils.
In such situations, the approval for land disposal may be based on the Environmental Soil Quality Guidelines
(see below) or other overseas guidelines on a case-by-case basis.