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EHSs and the EPCRA emergency planning requirements

What is purpose of the list of extremely hazardous substances in regards to the emergency planning requirements of EPCRA?

The extremely hazardous substances list and its threshold planning quantities are intended to help communities focus on the substances and facilities of most immediate concern for emergency planning and response.  However, while the list includes many of the chemicals which may pose an immediate hazard to a community upon release, it does not include all substances which are hazardous enough to require community emergency response planning.  There are tens of thousands of compounds and mixtures in commerce in the United States, and in specific circumstances many of them could be considered toxic or otherwise dangerous.  The list represents only a first step in developing effective emergency response planning efforts at the community level.  Without a preliminary list of this kind, most communities would find it very difficult to identify potential chemical hazards among the many chemicals present in any community.

Similarly, threshold planning quantities are not absolute levels above which the extremely hazardous substances are dangerous and below which they pose no threat at all.  Rather, the threshold planning quantities are intended to provide a "first cut" for emergency response planners in communities where these extremely hazardous substances are present.  Identifying facilities where extremely hazardous substances are present in quantities greater than the threshold planning quantities will enable the community to assess the potential danger posed by these facilities.

Communities also will be able to identify other facilities posing potential chemical risks and to develop contingency plans to protect the public from releases of hazardous chemicals.  Sections 311 and 312 of Title III provide a mechanism through which a community will receive material safety data sheets and other information on extremely hazardous substances, as well as many other chemicals, from many facilities which handle them.  A community can then assess and initiate planning activities, if desirable, for extremely hazardous substances below the threshold planning quantity and for any other hazardous substances of concern to them.

In addition to the assistance provided by the extremely hazardous substances list and the threshold planning quantities, community emergency response planners will be further aided by the National Response Team's Hazardous Materials Emergency Planning Guide.  A separate notice of availability of this document was published in the Federal Register on March 17, 1987 (52 FR 8360, 61) as required under Section 303(f) of Title III.  The planning guide was supplemented in December 1987 with the Technical Guidance for Hazardous Analysis to assist local emergency planning committees in evaluating potential chemical hazards and setting priorities for sites.  This technical document provides more detailed guidance on identifying and assessing the hazards associated with the accidental release of hazardous substances on a site- specific basis.  It addresses considerations such as the conditions of storage or use of the substance (e.g., conditions of temperature or pressure); its physical properties (e.g., physical state - solid, liquid, or gas); volatility; dispersibility; reactivity; location (e.g., distance to affected populations); and quantity.  

EPA, FEMA, the States, CMA, other industry and trade associations, and public interest groups developed a booklet, It's Not Over in October, to offer suggestions to local emergency planning committees to help them implement Title III.