United States                   Office of Solid Waste                   EPA 530-R-10-001
             Environmental Protection         and Emergency Response                      April 2011
             Agency                                                   www.epa.gov/emergencies
     EMERGENCY PLANNING AND COMMUNITY RIGHT-TO-KNOW ACT

            Amendments to Rule for Extremely Hazardous Substances (EHS) and
                Threshold Planning Quantities (TPQs) for Solids in Solutions
Introduction

EPA has proposed amendments to revise the way the regulated community applies the threshold
planning quantities (TPQs) for Extremely Hazardous Substances (EHS) that are non-reactive solid
chemicals in solution form. Facilities with a solid EHS in solution are subject to the Emergency
Planning requirements of 40 CFR 355 subpart B if the amount of solid chemical on site, when
multiplied by 0.2, equals or exceeds the lower published TPQ. With these amendments,  EPA
modified the assumptions used to develop the TPQs for solid EHS chemicals in solution based on
available data that show less potential for the solid chemical in solution to remain airborne in the
event of an  accidental release.  Previously, EPA assumed that 100% of an  EHS chemical could
become airborne in the event of an accidental release.


Who is Affected by This Rule?

Organizations and facilities subject to section 302 of the Emergency Planning and Community Right-
to-Know Act (EPCRA) and its implementing regulations found in 40 CFR 355 subpart B may be
affected by this rule.  To determine whether your facility is affected by this action, you should carefully
examine the applicability provisions of 40 CFR part 355. The proposed action will neither increase
nor decrease requirements for SERCs and LEPCs.

There are 157 EHS chemicals that are solids at ambient temperature, which could potentially be
affected by this change, if they are handled by facilities  in a solution form (the affected chemicals are
identified in Appendix C of the Technical Support Document, which in is the docket to this rule).
These 157 chemicals also appear with two TPQs (the higher TPQ is 10,000 pounds) in Appendices A
and B of 40 CFR part 355.  Additionally, this rule will not apply for the 12 solid EHS chemicals that are
reactive solids (noted as footnote "a" in Appendices A and B of 40 CFR part 355).


Why is EPA Proposing These Changes?

On October 11, 2000, Syngenta (formerly Zeneca, formerly ICI Americas) filed a lawsuit requesting
EPA to either delete Paraquat Dichloride from the Extremely Hazardous Substances (EHS) list or
raise its Threshold Planning Quantity (TPQ).  In 1994, EPA had previously denied their petition to
delete the chemical.  Syngenta claimed:

         The inhalation toxicity tests using very small  particles are not relevant data to  use for
         listing the chemical as an EHS.
         It is highly unlikely that inhalable particles or vapors of Paraquat Dichloride could be
         become airborne during an accidental release.  Paraquat Dichloride is only manufactured,
         processed, and used in solution form and it has a very low vapor pressure.
         EPA did not explain why a greater potential for airborne dispersion for solids in solution
Office of Emergency Management                                                      Factsheet

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EPCRA: EHS TPQ Solids in Solutions                                                   April 2010

          exists as opposed to liquid chemicals when setting the TPQs.

On January 31, 2003, the court granted EPA's motion for voluntary remand to reconsider the petition
and dismissed Syngenta's complaint.  In a letter to Syngenta on November 21, 2003, EPA reaffirmed
its denial to delete Paraquat Dichloride from the EHS list based on its inhalation toxicity.  However,
the Agency agreed to consider a revision to the TPQ for Paraquat Dichloride in the context of a
proposed rule to amend the TPQ for all EHS chemicals handled as solids in solution.
What is EPA's Rationale for the TPQ Changes?

While compiling the new TPQ changes, EPA took several factors into account.  Such factors
included:
      Development of existing TPQs;
      Syngenta's petition for changing paraquat Dichloride's TPQ and the claims against EPA;
      The basis for existing solids in solutions in TPQ; and
      Airborne dispersion of solids in solution.


What Are the Economic Impacts of the TPQ Changes?

For facilities with an EHS that exists as a solid in solution, the emergency planning notification is
currently required if the amount of solid by weight meets or exceeds the lower published TPQ for that
chemical. Solid EHSs have another higher TPQ of 10,000 pounds that applies only if the EHS is not
in solution, has a  particle size equal to or greater than 100 microns, is not molten, and does not have
a National Fire Protection Association (NFPA) reactivity rating of 2, 3, or 4.

The proposed rule would subject facilities with a solid EHS in solution to the emergency planning
requirements if the amount of solid chemical on site, when multiplied by 0.2, equals or exceeds the
lower published TPQ. The effect would be to allow facilities to have up to five times larger amounts of
EHS solids  in solution on site than before without being subject to the above emergency planning
requirements.

Because facilities currently with EHS solids in solution on site above the TPQ are assumed to have
already completed emergency planning notification, we expect that this proposed rule will neither
increase nor decrease the burden for facilities who have already complied.


Where Do I Go  For More Information?

For more information on the proposed rule, please visit the EPCRA page located on the OEM Web
site: http://www.epa.gov/emergencies/content/lawsregs/epcraover.htm.
Office of Emergency Management                                                     Factsheet

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