Abstract
Soil samples were collected at 25 points in a 10m×10m highly contaminated area by lead around the old shooting range in Heiwa Park. Also, soil samples were collected vertically from surface to 90cm depth at the center of same area. Surficial and vertical lead profiles were determined.
The results obtained in this study were summarized as follows.
1) There is a great variability among obtained data of surface soil concentrations. For surface soils, water-soluble concentrations and contents of lead were much higher than standards at all points.
2) Soil concentrations of lead collected at the far from walking trail were higher than the near of walking trail. Ratio of water-soluble concentrations or contents of lead to total lead concentration is higher near the walking trail.
3) The soil collection method of 5 points mixing is mostly effective for the survey of soil contamination at the shooting range.
4) Lead derived from bullet has been mostly remained until 20cm depth. But water-soluble concentration at 90cm depth exceeds soil standard.
5) Using sequential extraction procedure, vertical transformation of lead adsorption type to the soil and dynamic behavior of lead in soil are examined.
6) The dose derived from oral intake of contaminated soil near the walking trail easily exceeds TDI of lead. Potential health risks are still high around the old shooting range.
