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FACT SHEET: Specifics about Provisions Related to

Emergency Reciprocating Internal Combustion Engines


ACTION

  •  On January 14, 2013, the Environmental Protection Agency finalized amendments to the National Emissions Standards for Hazardous Air Pollutants (NESHAP) for stationary reciprocating internal combustion engines (RICE).
  • In this rulemaking, EPA addressed several petitions for reconsideration, legal challenges and new technical information from stakeholders, including industry and environmental groups, which were brought to the EPA’s attention after publication of the standards in 2010.
  • The final amendments will ensure that the standards are cost effective, achievable, and protective.
  • The final amendments will reduce particulate matter and sulfur dioxide emissions by requiring the use of cleaner fuel. The EPA has information that the majority of emergency engines do not use the cleaner fuel called ultra low sulfur diesel or ULSD. The EPA expects the reductions to be significant.
  • Pollutants emitted from diesel engines are known or suspected of causing cancer and other serious health effects including:
    • Aggravation of respiratory and cardiovascular disease
    • Changes in lung function and increased respiratory symptoms
    • Premature death in people with heart or lung disease
    • Neurological, cardiovascular, liver, kidney health effects, and also effects on immune and reproductive systems.
    • Requirements to report annual usage of emergency engines will provide data for EPA and
      the states to better understand the health impacts and the emissions that result from the
      engines.
  • Requirements to report annual usage of emergency engines will provide data for EPA and
    the states to better understand the health impacts and the emissions that result from the
    engines.
  • EPA is also revising the new source performance standards (NSPS) for stationary internal
    combustion engines to ensure consistency with the RICE NESHAP. In particular,
    specifying how the NSPS standard will apply to emergency engines used for demand
    response purposes.

EMERGENCY DEMAND RESPONSE

  • EPA is specifying how NESHAP and NSPS standards will apply to a category of engines called emergency engines.
  • Emergency engines may be used to prevent electrical outages and to test and maintain engines for up to a total of 100 hours per year.
  • In 2015, emergency engines will be required to use cleaner fuel -- ULSD -- if they
    operate, or commit to operate, for more than 15 hours annually as part of blackout and
    brownout prevention.
    • Switching to cleaner fuel will reduce emissions of hazardous air pollutants,
      particulate matter and sulfur dioxide. Our information shows that only a small
      percentage of emergency engines currently use ULSD fuel. Using cleaner burning
      fuel will result in lower emissions.
  • Starting in 2015, entities with 100 horsepower (hp) or larger engines that operate, or commit to operate for more than 15 hours and up to 100 hours per year as part of blackout and brownout prevention will need to collect and submit an annual report
    including location, dates, and times of operation.
    • Reporting requirements ensure compliance with the regulations and provide
      information about the air pollution impacts of the engines.
  • A combined total of 100 hours per year may be used to prevent blackouts and brownouts without meeting emission limits for the following purposes:
    •  maintenance and testing,
    • emergency demand response for Energy Emergency Alert Level 2 situations,
    • responding to situations when there is at least a 5 percent or more change in voltage,
    • operating for up to 50 hours to head off potential voltage collapse, or line overloads, that could result in local or regional power disruption.
  • The rules restate that in an emergency, such as hurricane or ice storm, any emergency engine of any size can operate without meeting federal control requirements or emission limits.
  •  Emergency engines that commit to run less than 15 hours year as part of blackout and brownout prevention can operate without meeting federal control requirements or emission limits.

BACKGROUND

  •  In 2004, EPA finalized the first regulation for stationary RICE greater than 500 HP
    located at major sources of HAP. In 2008, EPA finalized regulations for new RICE less
    than or equal to 500 HP located at major sources and new RICE located at area sources.
  • On March 3, 2010, EPA promulgated NESHAP for existing stationary compression ignition RICE that are used at:
    • area sources of air toxics emissions and constructed or reconstructed before June
      12, 2006,
    • major sources of air toxics emissions, have a site rating of less than or equal to
      500 HP and constructed or reconstructed before June 12, 2006,
    • major sources of air toxics for non-emergency purposes, have a site rating of greater than 500 HP and constructed or reconstructed before December 19, 2002.
  • On August 20, 2010, EPA promulgated NESHAP for existing stationary spark ignition (SI) RICE that are used at:
    • area sources of air toxics emissions and constructed or reconstructed before June 12, 2006, major sources of air toxics emissions, have a site rating of less than or equal to 500 HP and constructed or reconstructed before June 12, 2006.
  • After the publication of the final rules in 2010, various stakeholders raised a number of issues through lawsuits, petitions for reconsideration of the final rule and other communications. The stakeholders requested that EPA reconsider standards for operation of emergency engines. EPA granted the petitions, and, to address the issues, is making these amendments.
  •  EPA proposed amendments on May 22, 2012. A public hearing was held in Washington D.C. on July 10, 2012, and comment was accepted on the proposed amendments through August 9, 2012. EPA has evaluated the issues raised and has made amendments based on our assessment of the comments provided.

FOR MORE INFORMATION

  • The rule is posted at: http://www.epa.gov/ttn/oarpg/new.html.
  • For more information on how to comply with the rule, please see: http://www.epa.gov/ttn/atw/rice/ricepg.html.
  • Today’s rule and other background information are also available either electronically at
    http://www.regulations.gov, EPA’s electronic public docket and comment system, or in
    hardcopy at the EPA Docket Center’s Public Reading Room.
    • The Public Reading Room is located in the EPA Headquarters Library, Room
      Number 3334 in the EPA West Building, located at 1301 Constitution Ave., NW,
      Washington, D.C. Hours of operation are 8:30 a.m. to 4:30 p.m. eastern standard
      time, Monday through Friday, excluding federal holidays.
    • Visitors are required to show photographic identification, pass through a metal
      detector and sign the EPA visitor log. All visitor materials will be processed
      through an X-ray machine as well. Visitors will be provided a badge that must be
      visible at all times.
    • Materials for this action can be accessed using Docket ID No. EPA-HQ-OAR-2008-0708.
  • For further information about the action, contact Melanie King of EPA’s Office of Air
    Quality Planning and Standards, Sector Policies and Programs Division, Energy
    Strategies Group at (919) 541-2469 or by email at king.melanie@epa.gov.


Printable version of the fact sheet

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