Commonly used Sediment Quality Guideline Screening Levels

The attached tables provide some chemical-specific screening levels (SLs) used in evaluating sediments proposed for aquatic discharge from dredging and other activities. These screening levels have been developed for a standard list of chemicals, and are designed to be protective of direct biological effects to benthic and aquatic organisms. An evaluation of sediment quality frequently starts with comparison of chemical analytical results to corresponding chemical SLs.

EPA Regional Screening Levels (RSLs) can be used for initial screening of potential human exposures. These are risk-based concentrations derived from standardized equations combining exposure information assumptions with EPA toxicity data. These RSLs are considered by EPA to be protective for humans (including sensitive groups) over a lifetime. The SLs contained in the attached SL table are generic; they are calculated without site-specific information; these are not always applicable to a particular site and do not address non-human health endpoints, such as ecological impacts. An initial screening of potential current human health risks associated with exposure to sediments could be made using the values for residential exposure to soils. (Note: these were formerly called Preliminary Remediation Goals, or PRGs. Reference: United States Environmental Protection Agency Regions 3, 6, and 9. Regional Screening Levels for Chemical Contaminants at Superfund Sites). Additionally, EPA has compiled a number of sediment quality values (SQVs) that have been developed for dioxin.