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Air Toxics: Current Status, New Directions. Kenneth L. Mitchell, Ph.D.; Chief Air Toxics Assessment & Implementation U.S. Environmental Protection Agency Atlanta, Georgia. Good Afternoon!. What are Air Toxics? Program Overview Current Status Future Directions. Six“Criteria”
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Air Toxics: Current Status, New Directions Kenneth L. Mitchell, Ph.D.; Chief Air Toxics Assessment & Implementation U.S. Environmental Protection Agency Atlanta, Georgia
Good Afternoon! • What are Air Toxics? • Program Overview • Current Status • Future Directions
Six“Criteria” Pollutants O3, NO2, SO2, Pb CO, PM Mobile Source Pollutants 21 Chemicals & Mixtures The Federal Clean Air Act Hazardous Air Pollutants (Air Toxics) 187 Chemicals & Compounds What do we mean by “Air Toxics?”
Kidney,Liver Damage Cancer Asthma,Chronic Bronchitis Skin Rashes Developmental Problems in Children Birth Defects,Miscarriages Cough,ThroatIrritation Nervous System Damage Why are air toxics a problem? Millions of Sources Many are Highly Toxic Some Persist & Bioaccumulate Sources/Populations Colocated
WIND DIRECTION A B BIOACCUMULATION IN FOOD DERMAL INHALATION WIND DIRECTION TRANSFORMATION WET DEPOSITION DISPERSION DRY DEPOSITION EVAPORATION/REENTRAINMENT IN AIR CANCER TARGET ORGAN/TISSUE INGESTION OTHER NON-CANCER ENDPOINTS EXCRETION INTAKE/UPTAKE
There Are Sources Everywhere! Courtesy of Sustaining the Environment and Resources for Canadians
Types of Sources Major Sources 10 TPY or more of one HAP Or 25 TPY or more of a combination of HAPS Area Sources Less than 10 TPY of one HAP Or Less than 25 TPY of a combination of HAPS
Types of Sources Outdoor Air Indoor Sources Not regulated but pose (on average) 3-5 times the concentrations of outdoor air Mobile Sources On- and Off-road; Engines, fuels, and operation all contribute to pollution; 21 MSATs
THE NATIONAL AIR TOXICS PROGRAM (Stationary, Mobile, and Indoor Air Sources) Regulatory Approaches Risk Assessment Methods for Facility Specific & Community-Scale Risk Decision Criteria for Facilities and Communities Voluntary Reduction Options Education and Outreach SLT Program Structure Design Achieve Meaningful Reductions At The Local Level
Residual Risk – Mandate from Congress • Assess risks from stationary sources that emit air toxics after technology-based (MACT) standards are in place • Set additional standards if MACT does not protect public health with an “ample margin of safety” • Set additional standards if necessary to prevent adverse environmental effects
Residual Risk – Status • Coke ovens – April 2005 • March 2006 • Industrial cooling towers • Magnetic tape • Ethylene oxide sterilizers • Gasoline distribution • Dry cleaning – July 2006 • HON – December 2006 • Halogenated Solvents – December 2006
Residual Risk – New Directions • Develop “total facility low-risk demonstration (TFLRD)” rule • Develop comprehensive or generic residual risk rule (GRRR)
Area Sources – Current Status • The Integrated Urban Strategy was published July 19, 1999 • Identified chemicals of concern • Identified initial list of area source categories • 70 source categories have been listed • Listing completed in November 2002 • Source categories required to be “subject to regulation” • 16 rules completed • 4 under court order 20 of the 70 Standards
Area Sources – Recent Additional Court Ordered Schedule • Dec. 15, 2006 4 categories • June 15, 2007 6 categories • Dec. 15 2007* 10 categories • June 15, 2008 10 categories • Dec. 15, 2008 10 categories • June 15, 2009 10 categories 50 Categories *3 area source standards subject to CAA 112(c)(6) (related to PBT chemicals) must be promulgated by this date.
Area Sources – Future Directions • National Rulemaking Approach • Establish national standards for source categories that have a national level of concern • Flexible Rulemaking Approach • Enact a rule, covering a set of categories, that will regulate how categories are controlled at the local level based on local needs • EPA will provide guidance on control approaches
Mobile Source Air Toxics (MSATs) – Current Status • In March 2001, EPA published first MSAT rule • Toxics emissions performance standard for gasoline • Refinery-specific baselines to ensure no backsliding from 1998-2000 performance • No additional standards for fuels or vehicles • Identified data gaps and committed to additional research • Committed to additional rulemaking to evaluate the need for and feasibility of additional controls
Mobile Source Air Toxics – Future Directions • Proposed Rule signed on February 28, 2006 • Public hearing on April 12 • 60-day comment period (through May 30th) • Final rule by February 9, 2007
Mobile Source Air Toxics – Future Directions • Benzene content standard for gasoline • Vehicle standards • Exhaust emissions • Evaporative emissions • Gas can standards
Diesel Exhaust – Current and Future Directions • Building on the successes of EPA’s regulatory and voluntary efforts to reduce emissions from diesel engines, EPA has created the National Clean Diesel Campaign (NCDC) • Successful implementation of the 2007 Highway Engine Rule and the Clean Air Nonroad Diesel Rule • Develop new emissions standards for locomotive and marine diesel engines • Promote reduction of emissions for existing diesel engines through cost-effective and innovative strategies, including use of cleaner fuels, retrofitting and repairing existing fleets, idling reduction among others
Thanks for your attention! Dr. Ken Mitchell U.S. Environmental Protection Agency (404) 562-9065 mitchell.ken@epa.gov http://www.epa.gov/region4/air/airtoxic/index.htm