350 likes | 433 Views
PM 2.5 NAAQS October 26, 2004 ARIPPA. Presented by: Divya Harrison Trinity Consultants (240) 379-7490 dharriso@trinityconsultants.com. trinityconsultants.com. About Trinity. Founded in 1974 Core Focus in Air Quality Compliance, Permitting, Modeling & Expertise in other areas
E N D
PM2.5 NAAQSOctober 26, 2004ARIPPA Presented by: Divya Harrison Trinity Consultants (240) 379-7490 dharriso@trinityconsultants.com trinityconsultants.com
About Trinity • Founded in 1974 • Core Focus in Air Quality Compliance, Permitting, Modeling & Expertise in other areas • 1,200 projects per year • 18 offices, 200 staff • ISO 9001:2000 certified • Diverse client base, mostly industrial: • immediate service • high quality deliverables • solutions that provide long-term benefits • ARIPPA, associate member
What is PM2.5? • “Fine” particulate matter • Aerodynamic diameter less than 2.5 µm • For perspective, a human hair is about 70 µm in diameter
What Are The Sources of PM2.5? • Carbonaceous • Combustion activities • Inorganic • Dust • Secondary Formation • Condensation of gases • Atmospheric reactions • Primarily from nitrates and sulfates
What Are The Sources of PM2.5?(cont.) Cars, trucks, heavy equipment, wild fires, waste burning, and biogenics (VOCs, direct PM) Carbon Dust from road and construction Crustal Nitrates Cars, trucks, and power generation (NOx) Sulfates Ammonium Power Generation (SO2) Fertilizers and Animal Feed Operations (in combination with NOx/SOx sources) * Source: EPA
Why Are We Worried About PM2.5? • Fine particles are believed to pose the greatest risk to human health • Respiratory disease • Cardiovascular disease • Fine particles also contribute to regional haze issues
NAAQS Background (1 of 4) • The Clean Air Act identifies six common air pollutants that can injure health, harm the environment, and cause property damage • “Criteria” pollutants • Particulate matter (PM) is a criteria pollutant
NAAQS Background (2 of 4) • EPA is tasked with developing National Ambient Air Quality Standards (NAAQS) for criteria pollutants • Primary NAAQS – set at levels “allowing an adequate margin of safety…requisite to protect the public health.” (based on most sensitive individuals) • Secondary NAAQS – set at levels adequate to protect “human welfare,” where welfare is defined in terms of vegetation, soil, and visibility
NAAQS Background (3 of 4) • EPA established new NAAQS for PM2.5 in July 1997 (effective September 16, 1997) • 15 µg/m3 annual average (3-year average of annual mean, averaged spatially) • 65 µg/m3 24-hour average (3-year average of 98th percentile at each monitor) • Primary and secondary standards are equal
NAAQS Background (4 of 4) • Areas that don’t meet the NAAQS are designated as nonattainment areas • Designation is pollutant-specific • Subject to more stringent requirements • Additional controls • Emissions offsets • Fees
PM2.5 NAAQS Implementation • After much litigation following promulgation of the PM2.5 NAAQS, EPA is free to implement the standards • States began monitoring PM2.5 levels and speciation shortly after NAAQS promulgation • Monitoring data from 1998-2002 is being used to identify nonattainment areas and strategies
Overall Implementation Timeline (1 of 3) • 1998-2002 – Collect monitoring data • February 15, 2004 – Deadline for states to submit proposed designations • June 28-29, 2004 – EPA issued letters to states outlining EPA’s intended designations
Overall Implementation Timeline (2 of 3) • September 1, 2004 – Deadline for states to submit comments on EPA’s intended designations • November 2004 (Anticipated) – EPA to propose PM2.5 NA implementation guidance • November 2004 (Anticipated) – EPA issues final designations
Overall Implementation Timeline(3 of 3) • February 2005 (Anticipated) – Effective date of designations • May/June 2005 – EPA finalizes implementation rule • February 2008 – Deadline for states to update SIPs to incorporate NA provisions (3 years from effective date) • February 2010 – Attainment with standards required for most NA areas (5 years from effective date - dependent upon classification)
Comparison of Proposed NA Areas(cont.) • State proposals generally included only counties with monitored values greater than the NAAQS • EPA intended designations included additional counties based on potential contribution to monitored NA • Large emissions sources • High growth rate • High population and commuting levels
NSR Implications (1 of 4) • EPA will be requesting public comment on the proposed implementation methodologies • Part of proposed implementation rule to be published • Originally scheduled for early fall • Latest indications are that rule will not be proposed until after the election in November • EPA has been fairly tight-lipped about what will be proposed in the implementation rule • States are waiting (and getting frustrated)
NSR Implications (2 of 4) • EPA will likely propose that PM2.5 be regulated like other criteria pollutants • 100/250 tpy major source PSD threshold • EPA wrestling with the proposed significant emissions change level • Proposal anticipated to be between 5-15 tpy for PM2.5 and 40 tpy for precursors (if applicable) • STAPPA\ALAPCO proposal is 10 tpy for the PM2.5 significant emission rate
NSR Implications (3 of 4) • Control requirements (BACT/LAER) will likely focus on PM2.5 precursors • Nitrates • Sulfates • VOC • Ammonia
NSR Implications (4 of 4) • EPA anticipates giving states the authority to decide which precursors to regulate • States will also likely have full control in deciding the specific requirements for regulated precursors • RACT/BACT/LAER will be very case-by-case
Condensable Emissions • States require to consider condensable emissions in evaluating PM10 emissions from a source • Have not always been able to reliably quantify condensable emissions from sources due to variations in the PM10 test methods and emission factors • Condensable emissions are a significant component of PM2.5 emissions
PM2.5 Measurement Issues (1 of 3) • EPA Method 202 is reference method for condensable PM measurement • Accuracy and representativeness problems • Potentially significant positive and negative biases
PM2.5 Measurement Issues (2 of 3) • Method 202 uses water-filled impingers to cool the sample gas and to collect particulate matter • Exposure of the gas stream to a turbulent mixture of water droplets creates the opportunity for efficient mass-transfer operations and chemical reactions that do not occur during normal plume dispersion
PM2.5 Measurement Issues (3 of 3) • Sources of potential error • Gas-phase homogeneous reactions between ammonia and HCl or SO2 • Dissolution of SO2 and NOx into water • Incomplete purging of dissolved SO2 prior to the analyses for condensed material • Other biases?
Other Biases? • Conversion of SO2 and NOx occurs in Method 5 or Method 201A (front half of sampling train) • Can create vapor phase sulfuric acid and nitric acid that would not normally be formed in the vapor plume • Collected in Method 202 (back half of sampling train) as condensable PM
Measurement Alternatives? • Corrections for Method 202 • Compensate for homogeneous reaction biases related to NH3 and HCl (EPA Method 202) • Compensate for sulfate formation (SCAMD) • Dilution technique for Condensable PM • Uses a stack dilution sample system • Filtered air and mixing chamber for cooling and condensation • EPA’s replacement to Method 202? • Current being trialed as EPA Conditional Method 039
State PM2.5 Initiatives • NYSDEC – PM2.5 Policy • Modeling related requirements • NJDEP • Treatment of NSR permits in pending PM2.5 NA areas as NA NSR permit actions • Lots of Planning Concepts, but general frustration on lack guidance from EPA
What is Pennsylvania (et al) Doing? • Awaiting further guidance (implementation rule) from EPA before moving forward • Final designations will also have a big impact • Anticipating a similar approach for PM2.5 implementation as for 8-hour ozone implementation • Because of secondary formation of PM2.5 , transport of pollutants will impact attainment with the standards
What is Pennsylvania (et al) Doing? (cont.) • Pushing for greater “regional”approach to addressing PM2.5 transport issues • Asserts that some of PM2.5 problem is due to transport from outside the state • Also asserts that PA sources shouldn’t entirely pay the price if the problem is caused by external sources
PM2.5 Wrap-Up • NA requirements may be coming to an area near you • Be prepared for additional controls and more stringent requirements • Be careful of Method 202 as measurement technique for fine PM • Stay tuned – there are still many questions to be answered in the next few months
Divya Harrison (dharriso@trinityconsultants.com) Trinity Consultants 5320 Spectrum Drive, Suite C Frederick, MD 21703 Phone: 240 – 379 – 7490