Pierce County:
Soil Analysis
The maps below use data collected by the Department of Ecology where soil samples within Pierce County have been tested for lead and arsenic concentrations. Data was also retrieved from the US Census Bureau to determine the density of young children ( ages 0-10) within Pierce County. A variety of spatial analysis tools including the interpolation tool for Kriging analysis and IDW analysis. The Kriging analysis tool used a statistical model to analyze all the data points, to determine the concentration of lead and arsenic levels within Pierce County. The IDW analysis tool uses distance to weigh the data points, so that the data points that are closer to predetermined locations where the samples were taken have more influence than those who are further away.A raster reclassification tool was used to create raster data layers that showed the concentration of young children, lead, and arsenic, with four levels of classification for each layer based on the concentration (low-high) of lead or arsenic at each location.Finally,a raster calculator was used to determine where the highest concentrations of lead and arsenic were within Pierce County that also have the highest concentration of young children. This was determined by adding the values of each location as was determined by the concentration from low to high (rated on a scale from 1-4) in terms of children, arsenic, and lead values.
This map showcases where the areas that have a concentration of lead, arsenic and childrern are, with the darker the color, the higher the concentration. These areas would be recomended first, for toxic remediation as they have the potential to positively affect a greater concentration of people. This map also shows all the elementary schools in the area in relation to where higher amounts of lead and arsenic have been found. The reason elementary schools where chosen, is because at this age children are more likely to be found outside playing in the dirt. The consumption of the soil, or even exposure over the years could potentially lead to long term negative health affects.
This map was created in order to visualize any correlation between those who may be considered to be low-income, and the level of soil toxicity. A large number of mobile homes were located in areas that had low concentrations of lead, and arsenic. There were still some mobile homes found within areas that had high concentrations of lead and arsenic.
In this final map,golf courses are compared to the areas that are being recommended for soil remediation. The purpose of this map is to try and determine if there is a corelation between weatlh and amount of toxins found in the soil.But a suprisingly many privately owned golf courses can be found in areas where high concentrations of lead and arsenic can be found.