SOURCE ATTRIBUTION OF ELEVATED RESIDENTIAL SOIL LEAD NEAR A BATTERY RECYCLING SITE

A statistical methodology is developed to estimate site emission vs ur ban background contributions to elevated soil lead in areas adjacent t o historic lead processing facilities. The methodology is applied in a study of residential soil lead contamination near a former automotive battery recycling facility in Pennsylvania. The site contribution is scaled to deposition estimates from an atmospheric dispersion model wi th unit emissions. Indicator variables are used to represent the effec ts of lead-based house paint and other background sources. The statist ical model characterizes the observed soil lead concentration at each location as the sum of log-normally distributed components from the si te and urban background. The model is used to estimate the spatial pro file of mean contributions from the historic site emissions and the pr obability that the facility caused exceedances of a 500 mu g/g criteri on for remediation. The analysis helped to determine the extent of res ponsibility for cleanup and provided a rational basis for the terminat ion of residential sampling at farther distances from the site.