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HRS Toolbox

ToolboxThe HRS Toolbox page provides current guidance documents that may be used to determine if a site is a candidate for inclusion on the National Priorities List.


Hazard Ranking System Guidance Manual

The Hazard Ranking System Guidance Manual provides general and technical guidance for individuals involved in determining HRS scores and preparing HRS scoring packages. The manual clarifies terms and concepts in the HRS, presents strategies and specific guidance for scoring select HRS factors, and provides guidelines to assist in collecting and organizing relevant data. For more information on HRS Acronyms and Terms, access the Glossary of HRS Acronyms and Terms (A-L) and Glossary of HRS Acronyms and Terms (M-Z).

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Hazard Ranking System; Final Rules

The Hazard Ranking System (HRS) was established in 1982 to rank hazardous waste sites and has been revised twice, in 1990 and 2017.

The 2017 revision to the HRS was promulgated on January 9, 2017, and published in the Code of Federal Regulations (40 C.F.R. § 300) on Monday, July 1, 2019. The document provided below includes the 2017 final HRS Rule, as well as the preambles from the 1990 HRS Rule and the 2017 Revision.

Revised HRS Final Rule, 40 CFR 300 (7-1-19 Edition) (PDF) (197 pp, 21.6 MB, About PDF)

This 2017 revision added a component for evaluation of threats based on subsurface intrusion (SsI) into regularly occupied structures. The Groundwater Migration, Surface Water Migration and Air Migration Pathway evaluations remain unchanged from the 1990 Final Rule. The changes to the 2017 revision from the 1990 version include:

  • The addition of SsI as a component to Chapter 5, renaming the pathway from the Soil Exposure Pathway to the Soil Exposure and Subsurface Intrusion Pathway. Soil exposure is now a component of the new pathway, but the evaluation remains unchanged.
  • The SsI component integrated into Chapter 2 – Evaluations Common to All Pathways
  • Terms specific to the SsI component integrated into Chapter 1 – Definitions
  • The SsI component integrated into Chapter 7 – Sites Containing Radioactive Substances

The 1990 revision fulfilled mandates included in the 1986 Superfund Amendments and Reauthorization Act (SARA), resulting in a revision to every HRS evaluation factor. This revision to the Hazard Ranking System (HRS) was published in the Federal Register (Volume 55, Number 241) on Friday, December 14, 1990.

Revised HRS Final Rule, 55 FR 51532 (December 14, 1990) (PDF) (136 pp, 15.5 MB, About PDF)

Fact Sheets

This collection of fact sheets provides a quick reference guide for HRS scoring and HRS related topics. The fact sheets were published from November 1990 to April 2000.

HRS Scoring and Documentation Tools

The HRS Scoring and Documentation Tools collection currently contains the NPL Characteristics Data Collection Form, the Superfund Chemical Data Matrix (SCDM) and HRS Quickscore.

NPL Listing Policy Documents

The NPL Listing Policy Documents currently contains a Policy for Withdrawing a Proposal to List a Site on the NPL, a Policy for Obtaining a Govenor's Letter prior to Listing on the NPL, and a Policy for Clarifying the Definition of "Site" under the NPL.

HRS SsI Component Online Training Series

This is the first module of the HRS SsI Component training series. It focuses on presenting the basic structure of the SsI component and setting the stage for the subsequent modules, which will include more details on conducting an HRS evaluation using the SsI component, The intended audience for this presentation is primarily EPA Regional, state, and contractor staff with previous experience using the HRS for evaluating sites.

HRS SsI Tools and Resources

These tools and resources provide information to assist in evaluating a site using the HRS SsI component.

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