Human-Exposure-Based Screening Numbers Developed to Aid Estimation of Cleanup Costs for Contaminated Soil

The Office of Environmental Health Hazard Assessment (OEHHA) of the California Environmental Protection Agency announces the availability of the report, “Human-Exposure-Based Screening Numbers Developed to Aid Estimation of Cleanup Costs for Contaminated Soil, January 2005 revision”. This report is required by the California Land Environmental Restoration and Reuse Act (Escutia, Chapter 764, Statues of 2001) as part of the effort to develop soil screening numbers for a specific set of contaminants. The Act identifies a screening number as solely an advisory number , and has no regulatory effect. The screening numbers are intended to enable citizen groups, community organizations, property owners, developers, and local government officials to estimate the degree of effort that may be necessary to remediate a contaminated property. This document does not discuss how the public and government agencies might apply these screening numbers, once they are developed. The document is limited to the technical basis that will be used to compute the screening numbers.

A Microsoft Excel-based calculator was developed as a tool to assist in calculating the Hazard Index and Risk Index based on soil concentrations and/or soil gas concentrations using the California Human Health Screening Levels.  This tool, previously available for personal use only, was removed from the OEHHA website in 2014.