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Risk Assessment

Regional 4 Superfund X-Ray Fluorescence Field Operations Guide

This Field Operations Guide (FOG) was developed by the U.S. Environmental Protection Agency (EPA) Region 4 Superfund Division’s Scientific Support Section (SSS) risk assessment staff for consideration by Region 4 On-Scene Coordinators (OSCs) and Remedial Project Managers (RPMs). The intent of this FOG is to provide OSCs/RPMs with a methodology to collect defensible XRF data for lead and arsenic (approach may apply to other metals) in soil samples. This FOG also provides the methods to measure concentrations of contaminants in soil in a practical, cost-effective, and timely manner.

This FOG provides technical information and does not constitute rulemaking by the Agency. The intent of this FOG is to aid in the collection of high-quality soil data for select contaminants that can be used in risk assessments consistent with the expectations of SSS in its oversight role.

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