25-10-2012, 11:49 AM
ProUCL Version 3.0 User Guide
ABSTRACT
Exposure assessment and cleanup decisions in support of U.S. Environmental Protection Agency (EPA) projects are often
made based upon the mean concentrations of the contaminants of potential concern. A 95% upper confidence limit (UCL) of
the unknown population arithmetic mean is often used to: Estimate the exposure point concentration (EPC) term, Determine
the attainment of cleanup standards, Estimate background level mean contaminant concentrations, or Compare the soil
concentrations with site specific soil screening levels. It is important to compute a reliable, conservative, and stable 95% UCL
of the population mean using the available data.