The distribution of outdoor shooting ranges in Ontario and the potential for lead pollution of soil and water.

The distribution of outdoor shotgun shooting ranges in Ontario was determined to assess their potential for contributing to lead contamination of soil and water. Provincial soil maps were used to identify the soil type(s) occurring on each range, and to record their soil pH, organic matter content and clay content. Topographic maps (scale 1:50000) were used to identify any surface waters that existed on each range. At least 211 active shooting ranges exist in Ontario, of which 135 cater to shotgun sports. This number far exceeds earlier estimates. Soil pH data existed for 67 ranges, of which 50 had soil pH values >or=6.0, and 17 had pH values less than 6.0. Data for organic matter and or clay content were available for only 59 ranges. Approximately 10% of the ranges are on soils with low levels of both clay and organic matter. Seven of these ranges had a combination of low pH, and low clay and organic matter content, suggesting that they have a high potential for lead dissolution and mobilization. Surface waters that could potentially receive shot fall-out occurred on 94% of the ranges surveyed, although the precise location of the water with respect to the shot fall area at each range could not be determined. The majority of shooting ranges in the province occur on luvisolic soils: most of the ranges with a higher potential for lead solubilization occur on podzolic and brunisolic soils. This indirect approach to assessing the potential for lead pollution and mobility at shooting ranges allows a large number of ranges to be examined quickly, so that ranges with a high potential for lead contamination of soil and water can be selected for on-site measurements. This broad scale approach has allowed for the first time the point loading of metallic lead into the Ontario environment from shooting ranges to be determined, as well as the locations of ranges that may warrant investigation of lead pollution.