Direct PM 2.5 Emissions Data, Testing, and Monitoring Issues Ron Myers Measurement Policy Group SPPD, OAQPS

The Issues Collecting data needed for effective inventories and SIP development Collecting data needed for effective inventories and SIP development Selecting and prescribing appropriate test methods Selecting and prescribing appropriate test methods Improving monitoring in rules Improving monitoring in rules Implementing a transition period Implementing a transition period

Components of Direct PM 2.5 Filterable PM 2.5 Filterable PM 2.5 Solid or liquid material at stack temperature and higher (measured at ~250 o to 320 o F) Solid or liquid material at stack temperature and higher (measured at ~250 o to 320 o F) Stable in atmosphere and collected on ambient sampler Stable in atmosphere and collected on ambient sampler Condensable PM 2.5 Condensable PM 2.5 Vapor or gas at stack temperature Vapor or gas at stack temperature Condenses to liquid or solid at stack exit Condenses to liquid or solid at stack exit Stable in atmosphere and collected on ambient sampler Stable in atmosphere and collected on ambient sampler

Reasons to Consider Condensable PM 2.5 Emissions Condensable fraction of direct PM 2.5 can be significant Condensable fraction of direct PM 2.5 can be significant 10 to 50 percent of PM 2.5 emissions depending on control measures, temperature, other source-specific conditions 10 to 50 percent of PM 2.5 emissions depending on control measures, temperature, other source-specific conditions Combustion, metallurgical & wood product sources emit large quantities of vapors that condense to form PM 2.5 Combustion, metallurgical & wood product sources emit large quantities of vapors that condense to form PM 2.5 Acids (e.g., sulfuric acid from coal combustion) Acids (e.g., sulfuric acid from coal combustion) Neutralized acids (e.g., [NH 4 ] 2 [SO 4 ], NH 4 Cl ) Neutralized acids (e.g., [NH 4 ] 2 [SO 4 ], NH 4 Cl ) Organic materials (e.g., alkanes, PAHs, PCBs, PCDDs, acids) Organic materials (e.g., alkanes, PAHs, PCBs, PCDDs, acids) Metals (e.g., As, Se, Sb, Pb compounds) Metals (e.g., As, Se, Sb, Pb compounds) A small fraction of point sources are responsible for the majority of condensable PM emissions A small fraction of point sources are responsible for the majority of condensable PM emissions

Inventories and PM 2.5 Emissions Filterable PM Filterable PM Historically only PM included in databases Historically only PM included in databases Some States include filterable PM 10 or PM 2.5 Some States include filterable PM 10 or PM 2.5 Condensable PM Condensable PM Current knowledge is spotty Current knowledge is spotty Some SIP databases fail to include PM cond (even when required) Some SIP databases fail to include PM cond (even when required) When PM cond included - calculated from emissions factors (e.g., AP-42) that are often based on incorrect test methods When PM cond included - calculated from emissions factors (e.g., AP-42) that are often based on incorrect test methods Inventories reflect database errors Inventories reflect database errors Federal inventory includes some adjustments Federal inventory includes some adjustments Underestimate some sources’ contributions, overestimate others Underestimate some sources’ contributions, overestimate others

Effect on SIP Regulations Most current regulations do not address PM cond Most current regulations do not address PM cond Focus on filterable PM Focus on filterable PM Force control technology towards filterable PM Force control technology towards filterable PM Some regulations do include PM cond, but with incorrect test methods Some regulations do include PM cond, but with incorrect test methods Final rule creates a transition period Final rule creates a transition period Regulations addressing PM cond encouraged but not required Regulations addressing PM cond encouraged but not required Develop more precise and accurate PM cond emissions for inventories and rules Develop more precise and accurate PM cond emissions for inventories and rules

(Condensable PM Test Method) EPA Method 202 (Condensable PM Test Method) Preferred Preferred N 2 purge N 2 purge 80 F 80 F Neutralize quantitatively by titration Neutralize quantitatively by titration Optional No purge 250 F Over neutralize, measure sulfate, assume SO 3 Impact Impact 10-20X artifact 10-20X artifact Lose nitrates, chlorides Lose nitrates, chlorides Sulfate biased low, SO 3 biased high Sulfate biased low, SO 3 biased high Sample collected in cold water Organic PM extracted with solvent Organic PM extracted with solvent Water & solvent evaporated Water & solvent evaporated Residue weighed Residue weighed Procedures

Test Method Selection is Important for Measuring PM cond Variations of Method 202 commonly applied Variations of Method 202 commonly applied Method 202 can be (and often is) conducted incorrectly Method 202 can be (and often is) conducted incorrectly Without N 2 purge, dreaded artifacts can form (e.g., SO 2 gets trapped in water, reacts with other stuff to form psuedo-PM) Without N 2 purge, dreaded artifacts can form (e.g., SO 2 gets trapped in water, reacts with other stuff to form psuedo-PM) Artifacts can be > PM cond by orders of magnitude Artifacts can be > PM cond by orders of magnitude Amount of artifact is source-specific and test- specific – variable and unpredictable Amount of artifact is source-specific and test- specific – variable and unpredictable

EPA Activities to Resolve PM cond Test Methods Issues Recommending use of Method 202 with purge and use of condensable PM 2.5 (see Recommending use of Method 202 with purge and use of condensable PM 2.5 (see Assessing “improvements” to Method 202 Assessing “improvements” to Method 202 Apply technologies tested in Canada and US Apply technologies tested in Canada and US Reduce artifacts from ~10 mg to >2 mg Reduce artifacts from ~10 mg to >2 mg Revise M202 in Appendix M Revise M202 in Appendix M More precise (no options) More precise (no options) More accurate (reduce artifacts) More accurate (reduce artifacts) Post on EPA/EMC web site in July 2007 Post on EPA/EMC web site in July 2007 Propose in 2007/2008 Propose in 2007/2008 Promulgate 2008/2009 Promulgate 2008/2009

EPA PM 2.5 Transition Period Activities Recommending use of Method 201A (existing filterable PM 10 test method) with supplemental hardware for filterable PM 2.5 Recommending use of Method 201A (existing filterable PM 10 test method) with supplemental hardware for filterable PM 2.5 Revise Method 201A in Appendix M Revise Method 201A in Appendix M Add filterable PM 2.5 measurement Add filterable PM 2.5 measurement Available now on EPA/EMC web site as CTM-040 Available now on EPA/EMC web site as CTM-040 Propose 2007/2008 Propose 2007/2008 Promulgate 2008/2009 Promulgate 2008/2009 Encourage stakeholder testing for Total PM 2.5 Encourage stakeholder testing for Total PM 2.5

Other EPA Transition Period Activities Advance Dilution Sampling Method Advance Dilution Sampling Method Promote ASTM Standard development process Promote ASTM Standard development process Assess speciation capacity Assess speciation capacity Improve consistency mobile source methods Improve consistency mobile source methods Document benefits of improved monitoring Document benefits of improved monitoring Develop PM 2.5 CEMS Develop PM 2.5 CEMS Develop guidance on understanding and applying data uncertainty Develop guidance on understanding and applying data uncertainty

April 2008 SIP expectations States are encouraged to evaluate and control sources of condensable PM 2.5 that may be important in attainment strategies States are encouraged to evaluate and control sources of condensable PM 2.5 that may be important in attainment strategies However, emissions limits (e.g., RACT, RACM) in 2008 are not required to include condensable PM 2.5 However, emissions limits (e.g., RACT, RACM) in 2008 are not required to include condensable PM 2.5 If want credit for condensable PM 2.5 reductions, must ensure those reductions with enforceable emission limits If want credit for condensable PM 2.5 reductions, must ensure those reductions with enforceable emission limits

Your Direct PM 2.5 SIP Activities By transition period By transition period Collect information on PM 2.5 filterable and condensable Collect information on PM 2.5 filterable and condensable Include PM cond at your option Include PM cond at your option In new rules with appropriate test methods In new rules with appropriate test methods As supplemental testing with filterable PM As supplemental testing with filterable PM Incremental cost ≈$700 Incremental cost ≈$700 Populate emissions factors database Populate emissions factors database Use Electronic Reporting Tool to document emissions tests ( ) Use Electronic Reporting Tool to document emissions tests ( ) (

Your Direct PM 2.5 SIP Activities Post 2011 Post 2011 Use information obtained during transition period Use information obtained during transition period Improve direct PM 2.5 emissions inventory Improve direct PM 2.5 emissions inventory Revise control strategies Revise control strategies Revise or establish new PM 2.5 limits Revise or establish new PM 2.5 limits Not necessary to REVISIT old limits Not necessary to REVISIT old limits Must incorporate condensable PM in NEW limits Must incorporate condensable PM in NEW limits e.g. SIPs to make mid-course corrections e.g. SIPs to make mid-course corrections SIPs for 2006 PM 2.5 standards SIPs for 2006 PM 2.5 standards Improve monitoring methods Improve monitoring methods Improve management of short term emissions Improve management of short term emissions Start up/shut down/malfunction Start up/shut down/malfunction Continuous performance assessment Continuous performance assessment

Important Monitoring Elements Indicator of performance Indicator of performance Emission measurements Emission measurements Operating parameters Operating parameters Work practice Work practice Raw material or fuel content Raw material or fuel content Monitoring technique Continuous emissions monitor Continuous emissions monitor High Sensitivity PM monitor High Sensitivity PM monitor Continuous opacity monitor Continuous opacity monitor Continuous parametric monitoring Continuous parametric monitoring Monitoring frequency Averaging time

Summary - Direct PM 2.5 Emissions Issues Both filterable and condensable PM 2,5 are important components direct PM 2.5 Both filterable and condensable PM 2,5 are important components direct PM 2.5 Databases must address both for all sources to ensure effective control program Databases must address both for all sources to ensure effective control program Target significant sources Target significant sources Establish technologically correct regulations Establish technologically correct regulations Test methods and monitoring must correspond with emissions limitations Test methods and monitoring must correspond with emissions limitations You get what you measure You get what you measure