|How clean is clean? When do I have to remediate? What sampling methods must be used? What evaluation criteria are applied? Are there state or federal standards? Read on for soil contamination guidance!|
The U.S. Environmental Protection Agency (EPA) has developed Soil Screening Guidance as a tool for screening at National Priorities List (NPL) sites. This guidance presents a framework for developing soil screening levels (SSLs), focusing primarily on a simple methodology for developing site-specific screening levels, but also including generic soil screening levels and detailed models for more complete site conditions. The guidance can serve as a tool to expedite the evaluation of contaminated soils at sites addressed under the Comprehensive Environmental Response, C ompensation, and Liability Act (CERCLA), commonly known as Superfund. The guidance is intended to be used to screen out areas of sites, exposure pathways, or chemicals of concern from further consideration, assuming certain conditions are present, or to determine that further study is warranted at a site. Its use may significantly reduce the time it takes to complete soil investigations and cleanup actions at some sites, as well as improve the consistency of these actions across the nation. The guidance was written to enhance the efficiency of remedial investigation/feasibility study (RI/FS) work at NPL sites but may be utilized at corrective action sites or voluntary cleanup sites where site conditions are similar.
The Soil Screening Guidance presents three recommended methods for developing risk-based, soil screening levels, but emphasizes a simple, site-specific approach. The formulae and exposure assumptions used to develop the screening levels are based on "Ri sk Assessment Guidance for Superfund" and have been widely accepted in the Superfund program for a number of years. These levels are then compared to on-site soil contaminant levels. Generally, areas of a site which fall below the screening levels may be eliminated from further assessment. Areas above the screening levels generally warrant further evaluation of the potential risks that may be posed by site contaminants to determine the need for response a ction. The guidance is recommended for use as a screening tool where assumptions made in developing the tool (e.g., residential land use, no ecological concerns) are consistent with conditions found to determine if further study of specific portions of a site is warranted. The levels should not be interpreted to represent cleanup standards for a site. The Soil Screening Guidance is presented as Portable Document Format (PDF) files in three documents: (1) a Quick Reference Fact Sheet , which provides an overview of the development and use of soil screening levels; (2) a User's Guide , which provides details for implementing a simple methodology for calculating site-specific SSLs; and (3) a Technical Background Document (TBD) , which presents generic SSLs and the technica l foundation for the methodology for establishing SSLs. These documents are also available from the National Technical Information Service; see below for additional ordering information . In addition, EPA has developed a (4) Respon se to Comments document describing our response to comments received on the public review draft and the independent scientific peer review. Currently, only the Fact Sheet , User's Guide , and the TBD are available on the Internet.
This guidance is not a rule, does not have the force of a regulation, nor should it be interpreted to represent cleanup standards for a site. Use of the guidance is not legally binding either on EPA staff or on other parties; rather it is intended to be a tool available for use under appropriate site-specific conditions. NPL sites do not all meet the conditions necessary for its use; consequently, EPA does not expect this tool to be useful at all NPL sites. EPA staff applying the guidance have discreti on to follow it or diverge from it as site-specific conditions may warrant, and each site-specific action will be explained on its own record. Concentrations in soil above these screening levels do NOT automatically designate a site as dirty, nor trigger a response action. SSLs do not supersede existing federal or state ARARs that may affect selection of cleanup levels for soils.
The Soil Screening Guidance is available as a Portable Document Format (PDF) file. To view PDF files you must have Adobe® Acrobat® Reader software. For more information about Adobe® Acrobat® Reader, please view About Portable Document Format Files page. You can download PDFs and view and print them offline or you can configure your browser to view them online. The Adobe® home page provides instructions on how to configure your web browser to use the Adobe® Acrobat® Reader.
This fact sheet summarizes key aspects of the U.S. Environmental Protection Agency's (EPA) Soil Screening Guidance.
Fact Sheet: June 1996
EPA Document Number: EPA540/F-95/041
[PDF (213K) 12 pages]
EPA Document Number: EPA540/R-96/018
The Soil Screening Guidance is a tool developed by EPA to help standardize and accelerate the evaluation and cleanup of contaminated soils at sites on the National Priorities List (NPL) where future residential land use is anticipated. The User's Guide p rovides a simple step-by-step methodology for environmental science/engineering professionals to calculate risk-based, site-specific soil screening levels (SSLs) for contaminants in soil that may be used to identify areas needing further investigation at NPL sites.
EPA Document Number: EPA540/R-96/018
The Soil Screening Guidance is a tool developed by EPA to help standardize and accelerate the evaluation and cleanup of contaminated soils at sites on the National Priorities List (NPL) where future residential land use is anticipated. The User's Guide provides a simple step-by-step methodology for environmental science/engineering professionals to calculate risk-based, site-specific soil screening levels (SSLs) for contaminants in soil that may be used to identify areas needing further investigation at NPL sites.
Soil Screening Guidance: User's Guide
[PDF 425K, 49 pages]
Attachment A: Conceptual Site Model Summary
[PDF 417K, 19 pages]
The CSM summary forms and worksheets contain the information necessary to determine the applicability of SSLs to the site, and help focus data collection efforts to gather information needed to calculate SSLs.
Attachment B: Soil Screening DQOs for Surface Soils and Subsurface Soils
[PDF 57K, 6 pages]
This attachment illustrates the Data Quality Objectives (DQO) Process for surface soil sampling using the Max test, and for subsurface soil sampling. The completion of all the requirements set out in the DQO process during the implementation of the Soil Screening Guidance is needed to satisfy Superfund program objectives.
Attachment C: Chemical Properties for SSL Development
[PDF 123K, 9 pages]
This attachment provides the chemical properties necessary to calculate inhalation and migration to ground water SSLs for 110 chemicals commonly found at Superfund sites. Chemical properties for additional contaminants may be found in the Superfund Chemical Data Matrix (SCDM).
Attachment D: Regulatory and Human Health Benchmarks for SSL Development
[PDF 198K, 6 pages]
This attachment provides the regulatory and human health benchmarks necessary to calculate SSLs as determined by 1995 versions of either IRIS or HEAST.