Air Toxics An Update

1. Air ToxicsAn Update Kenneth L. Mitchell, Ph.D. U.S Environmental Protection Agency Atlanta, Georgia November 2005

2. The Air Toxics Risk Assessment Library Air Toxics Guidance

3. ATRA Reference Library • Volume 1: Technical Resource Manual (Complete) • Volume 2: Facility-specific Assessment (Complete) • Volume 3: Community-Level Assessment (In Peer Review) www.epa.gov/ttn/fera

4. Air Toxics Monitoring Screening Guidance • Region 4’s A Preliminary Risk-Based Screening Approach for Air Toxics Monitoring Data Sets • Easy to perform • Provides (generally) conservative results • Helps to evaluate whether there is a potential problem that needs further evaluation • We are responding to last minute comments and hope to publish by the end of the year

5. The Area Source Program An Update

6. Area Sources • Potential to emit less than 10 tpy for a single HAP and less than 25 tpy for combined HAP • Individual area sources are small emitters • Many sources emit less than 100 pounds of HAPs • Collectively, these sources are important toxic contributors, especially in urban areas 1999 NEI

7. Statutory Requirements • 112(c)(3) and 112(k) • List area source categories representing at least 90% of the emissions of the 30 listed urban HAP • Prepare a national strategy for urban air toxics • Subject categories to regulation and promulgate by 11/15/2000 • Achieve at least a 75% reduction in cancer incidence

8. Listing of Categories • The Integrated Urban Strategy was published July 19, 1999 • 70 source categories have been listed • Listing completed in November 2002 • Source categories required to be “subject to regulation”

9. Status • 15 standards have been completed • 5 categories are under consent decree:

10. Status of Remaining 50 Categories • 28 source categories have been initiated • Based on a toxicity-weighted prioritization • 22 remain unaddressed • Schedule under litigation • Final oral arguments scheduled for November • Expect court schedule sometime after that

11. Program Challenges • There are numerous facilities • Many small businesses • Most sources have not been regulated before • Most sources are difficult to locate • Most are not included in existing inventories • Most are not required to report under Title III • Many are not represented by trade associations • There are smaller amounts of emissions per facility but collectively can present a problem

12. Program Challenges • Resources are limited • Need to balanceaddressing the requirements and the high risk areas with resources and practical restraints for implementation • Need to provide for states that need regs and states with existing programs • Need to maximize co-benefit reductions

13. Implementation Challenges • Many states don’t have resources to take delegation • EPA will have to implement program where states do not take delegation • Need to minimize burden for all levels -- especially small businesses

14. Exploring New Ways of Doing Business • Explore options to nontraditional rulemaking • Explore pollution prevention approaches • Develop user friendly and cost effective control options • Develop innovative compliance measures • Simplified monitoring plans, reduced recordkeeping, self-certification for permitting

15. Proposed Area Source Framework Screening/Characterization of Source Categories Step 1 - Binning or National Rulemaking Approach Flexible Rulemaking Approach Step 2 – Two Rulemaking Approaches 1 Source Category Rulemaking 1 Rule/ Multiple Categories Control Options Control Options Pollution Prevention Options Pollution Prevention Options

16. Two Regulatory Approaches • 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

17. Focus on GACT • Can develop standards or requirements • 112(d)(5) – use of Generally Available Control Technologies or management practices • Advantages to using GACT: • Allows more flexibility • There is no floor to calculate • Cost effectiveness is considered

18. Potential Authorities • 112(k)(4) – encourage and support area wide strategies developed by state and locals • 112(l) – each State may develop and submit a program for implementation and enforcement • 301(a) – EPA can prescribe such regulations as are necessary to carry out its function under the Act.

19. Framework Status • Spring 2005 developed a white paper describing the concept and issues to be addressed • Summer 2005 created teams to help work on issues and develop implementation plan • Timeframe • By October 30 – completed implementation plan with details on how to implement framework • By December 30 – begin development of draft preamble language for flexible area source process rule

20. The Residual Risk Program An Update

21. Summary of Residual Risk Activities • Coke ovens rule promulgated 3/05 • Tightened standards moderately for a limited number of facilities • Set forth several general policies, principles; e.g., • Reinforced use of 2-step decision process: first determine acceptability, then ample margin of safety • Total facility risks could be considered in ample margin of safety determinations, not acceptability determinations • Intent to provide multiple risk metrics, move toward probabilistic assessments, where appropriate • Intent to improve multipathway and ecological risk assessments

22. Summary of Residual Risk Activities (cont.) • Several proposals for no further action • Gasoline distribution • Risks low, but not below statutory trigger (1 in a million cancer risk) • Additional controls could reduce risk minimally • Cost of controls was exorbitant • Proposal issued 8/05 • Ethylene oxide sterilizers • Maximum cancer risks near upper limit of “acceptable” • Additional controls unfeasible; process provides health benefits • Proposal approved by OMB; publication soon

23. Summary of Residual Risk Activities (cont.) • Proposals of no further action (cont.) • Industrial process cooling towers • MACT rule banned use of chrome as corrosion inhibitor • Assessment determined that risks from all other HAP were below statutory trigger, residual risk rule unnecessary • Proposal approved by OMB, publication soon • Magnetic tape manufacturing • Assessment determined risks to be below trigger, residual risk rule unnecessary • Proposal approved by OMB, publication soon

24. Summary of Residual Risk Activities (cont.) • One proposal imminent • Perchlorethylene dry cleaners • Risks generally high, even for some smaller area sources • Risks unusually high for some “co-residential” area sources – based on limited monitoring • Proposal aims to improve levels of control for major and area sources • Considering banning future location of area sources in residential buildings • Proposal release targeted for October

25. Summary of Residual Risk Activities (cont.) • Two proposals on horizon • Hazardous organic chemical manufacturing (HON) • Maximum cancer risks near upper limit of “acceptable” • Additional controls feasible, minimal risk reduction, moderate costs • Currently weighing “ample margin of safety” options for proposal; targeted date for release, 2/06 • Halogenated solvent cleaners (a.k.a. degreasers) • Maximum cancer risks near upper limit of “acceptable” • Currently weighing “ample margin of safety” options for proposal; targeted date for release, 2/06

26. Summary of Residual Risk Activities (cont.) • Court-ordered deadlines for final rules • Gasoline distribution, ethylene oxide, cooling towers, magnetic tape due 3/06 • Dry cleaners due 4/06 • HON, Degreasers due 12/06

27. Reducing residual risk burden for low risk sources • May seek comment on allowing low-risk HON or Degreaser sources to demonstrate compliance via risk assessment • Assessment must show risks below target • Emission rates used for assessment must be included in permit as limits • Developing process rule for whole facilities (TFLRD) • Considering alternative process for entire program (GRRR)

28. Total Facility Low Risk Demonstration (TFLRD) Rule

29. Summary of the TFLRD Rule • Voluntary process option available to facilities with at least one MACT source category on site • Step 1 -- Source conducts a total facility risk assessment • Sources referred to EPA’s Air Toxics Risk Assessment Reference Library for risk assessment guidance • Step 2 -- If they meet low risk criteria defined in rule, source submits risk assessment to permitting authority • Low risk criteria: maximum cancer risk < 1E-06, all non-cancer TOSHI values < 1, all ecological HQ values < 1

30. Summary (Cont.) • Step 3 -- Review and approval: We are evaluating several options • Could involve EPA review, state review, 3rd party review, or source self-certification and audit review • Step 4 -- Parameters from low risk demonstration must then be incorporated into Title V permit • Parameters become enforceable permit limits • Facilities that successfully complete this process are deemed to be in compliance with any current or future relevant 112(f) requirements • Subsequent changes at facility would trigger re-evaluation

31. Potential Benefits of TFLRD • Could achieve early risk reductions on a voluntary basis • Facilities might be motivated to comply with TFLRD if they can meet the requirements by making simple changes • Will “target” emission reductions under the current residual risk program, making them more cost-effective and justifiable • Should provide high quality site-specific emissions data for use in future assessments and emission reduction strategies

32. Status of TFLRD • EPA management briefed on TFLRD options in September, 2005 • Workgroup is currently developing a draft of the proposed rule • Proposed rule anticipated in early 2006

33. Generic Approach to Residual Risk The Generic Residual Risk Rule (GRRR)

34. Background: Current Residual Risk Program • Under the current Residual Risk program EPA will assess approximately 100 source categories • Each source category will be assessed individually • Inefficient approach • Total cost of the program will be between $25 million and $30 million • FY05 budget for Residual Risk is approximately $750K • As resources are reduced, more of the work must be accomplished in house • This will slow the progress of the program • May also result in inappropriate regulation

35. Background: Goals of a Generic Approach to Residual Risk • Efficient use of resources • By allowing us to focus most of our resources on the highest-risk sources while expending little effort on the low risk sources • We could also distribute the resource burden across EPA, states, and industry • Accurate characterization of risks • GRRR could accomplish this by focusing on risk assessments that use site-specific information

36. Overview of the Proposed Process for GRRRR • EPA develops single, generic process rule that applies to all sources in all source categories • Step 1: Sources submit information to EPA/ permitting authority • Sources could be required to conduct and submit a risk assessment • For this option we need to develop a review/approval process • Sources could be required to submit facility data (e.g. HAP emission rates, stack parameters) in model-ready format • EPA could then use this data to conduct risk assessments for all sources

37. Overview of the Proposed Process for GRRR (cont.) • Step 2: Based on the results of their assessments, sources are binned into low, medium, and higher risk categories • Low risk: Maximum cancer risk less than 1 in 1 million and non-cancer target organ specific hazard index < 1 • Medium risk: Above low risk criteria but below cancer risk of 100 in 1 million (non-cancer criteria?) • Higher risk: Above medium risk criteria

38. Overview of the Proposed Process for GRRR (cont.) • Low risk: Sources meet their 112(f) requirements • No risk reduction requirements under the residual risk program • Medium risk: Some sources must reduce risks further (considering costs/feasibility) • Higher risk: All sources must develop and implement a risk reduction plan that is approved by EPA • Risk reduction plan should bring source at least to the medium risk range

39. Options for Addressing Sources that Do Not Meet Low Risk Criteria • Option 1: Sources must develop a risk reduction plan that is approved by EPA • This option would likely be reserved for highest risk sources • Option 2: Write a limited number of source category rules • Under this option we could combine multiple source categories into a single rule and allow site-specific compliance based on risk • Option 3: Sources could be required to add new source MACT (or most stringent MACT requirements for source category) • Option 4: Sources could be required to choose control options from a control technology table • Option 5: EPA could delegate oversight of risk reduction to states (in some cases) • States that accept delegation would be responsible for developing a risk reduction plans

40. Next Steps • We are working with other EPA offices to further develop this concept • Engage stakeholders and obtain input • Form a formal workgroup and begin rule development???

41. The 1999 National Air Toxics Assessment (NATA) An Update

42. National Air Toxics Assessment (NATA) activities are… • A number of technical support activities designed to provide all parts of EPA's Air Toxics Program with quantitative, policy-relevant, and consistent information: • Emissions inventories • Monitoring network • Air quality, exposure, and risk modeling (called the National Scale Assessment) • Research on effects and assessment tools

44. What is the National Scale Assessment? • Characterization of air toxics exposure and risk across the nation • Nationwide assessment with census tract resolution for 177 HAPs plus diesel PM • Emissions, modeled ambient concentrations and estimated inhalation exposures from outdoor sources • Cancer and noncancer risk estimates for the 133 HAPs with health data based on chronic exposures

45. X X X X X X

46. Goals of the Initial National-Scale Assessment • Identify air toxics of greatest concern • Characterize contributions of different emission sources to exposure and risk • Prioritize collection of new data • Provide a baseline (with ambient data) to track trends and measure progress against goals • Tools for State/Local/Tribal Agencies (and EPA) to prioritize pollutants, emission sources and locations of interest • Provides a starting point for local-scale assessments • Focuses community efforts • Informs monitoring programs • A few pieces of the air toxic puzzle

47. acetaldehyde acrolein acrylonitrile arsenic compounds benzene beryllium compounds 1,3-butadiene cadmium compounds carbon tetrachloride chloroform chromium compounds coke oven emissions 1,2-dibromoethane (ethylene dibromide) 1,2-dichloropropane (propylene dichloride) 1,3-dichloropropene ethylene dichloride (1,2-dichloroethane) ethylene oxide formaldehyde hexachlorobenzene hydrazine lead compounds manganese compounds mercury compounds methylene chloride (dichloromethane) nickel compounds polychlorinated biphenyls (PCBs) polycyclic organic matter (POM) quinoline 1,1,2,2-tetrachloroethane tetrachloroethylene (perchloroethylene) trichloroethylene vinyl chloride diesel particulate matter Etc. Some of the pollutants included in the National-Scale Assessment

48. Limitations of the National-Scale Assessment • Inhalation exposure only • Chronic exposures only • 1999 emissions data • Sources of indoor origin generally excluded • 50-km modeling range • Focuses on average/median exposures, not individual extremes • Census tract-level calculations; county-level and higher presentations

49. Components of the NATANational-Scale Assessment Comparison with Ambient Monitoring Data Emission Inventory Development Emission Processing (EMS-HAP) Air Dispersion Modeling (ASPEN) Inhalation Exposure Modeling (HAPEM) Dose-Response Assessment Risk Characterization

50. Improvements Over the 1996 National Scale Assessment • Improved quality of inventory • Expanded coverage to include nearly all HAPs • Improved technical quality of modeling analyses • Responded to many of SAB comments • Used latest health risk information • Improved presentation of results • More transparent and accessible website data • Local scale mapping tools