Western Regional Technical Air Quality Studies:

support for Ozone and other Air Quality Planning in the West

Tom Moore

Air Quality Program Manager

Western Regional Air Partnership

WESTAR Council Meeting

Salt Lake City, UT

October, 30, 2012

Western ozone precursors - key emissions sources

• Power plants decreasing markedly

• Mobile sources controlled and emission rates decreasing markedly through federal rules and state testing programs

• Fire effects receiving intensive study

• Biogenics

• Oil and gas

• All sources currently being studied in comprehensive regional modeling analysis framework – starting with 2008 base year– West-wide Jumpstart Air Quality Modeling Study

(WestJumpAQMS)

Data from EPA Clean Air Markets Division

DEASCO3 & PMDETAIL projects - purposes & goals

• Assess fire’s impact on elevated ozone and PM episodes with retrospective studies• Studies of fire and ozone in 2002 through 2008

• Studies of fire and PM in 2008 and 2011

• Outcomes• Support future collaborative FLM-state ozone and PM air quality

planning

• Develop “lessons learned”, basic analysis rules for fire-ozone / fire-PM episodes, and online tools for FLM-state air quality planning

• Prepare and implement planning-grade fire emissions inventories in FETS suitable for SIP work by states & FLMs

• Leverages WestJumpAQMS and western modeling framework

• Products for FLMs and states to use in SIP processes and Exceptional Events demonstrations

Applying Improved Biogenics Emissions tools - considerations for AQ Modelers and Planners

• Evaluate sensitivity of ozone and PM to biogenic emission improvements

• Further improvements to biogenic emissions in urban areas would require field studies

• Biogenic emissions will respond to changes in climate– Plant distributions change

– Emissions responses to temperature and drought

• Recovery of vegetation and biogenic emissions after major fires and insect outbreaks– Use typical vegetation density as basis for AQ planning?

– Do different species regrow?

Western Oil & Gas Emission Inventory Efforts

• Why such a focus on the O&G industry sector?• Recent modeling in Colorado Ozone NAA indicates O&G could

account for up to 50% of VOC and 10% of NOx NAA inventories

• Percentages could be even higher in other Rocky Mountain States

• Current work:• Considers every major oil and gas production basin in the Rocky

Mountain states, including New Mexico, Utah, Colorado, Wyoming, Montana and North Dakota

• All major oil and gas source categories and all major criteria pollutants: NOx, VOC, CO, PM, SOx

• Provides updated, regionally consistent methodology which combines state-permitted sources databases with direct industry survey for some source categories

• Latest oil and gas production / well statistics from IHS database

• Most detailed oil and gas emissions inventories to date

3-State Air Quality Study - Objectives

• EPA R8, NPS, USFS, BLM, States of UT, WY, CO

• Facilitate more complete and consistent air quality analysis for NEPA and other air quality decisions

• Improve timeliness

• Reduce duplication of air quality analyses resulting in lower costs

• Improve collaboration through data warehouse and modeling, using agreed upon data and protocols

Western Modeling Framework - Source Apportionment

• Regional Ozone Source Apportionment – 2 types– Type 1 - Anthropogenic vs. Natural contributions

– Type 2 - Ozone formation potential, all sources, including Natural

• Particulate Source Apportionment– Sulfate

– Nitrate

– Ammonium

– Primary PM (carbon and dust)

• 2 tiers of Source Apportionment Modeling

Air Quality planning requirements for Ozone NAAQS

• SIPs due from each state for area(s) in the state violating

• All 50 states also complete a “good neighbor” [CAA §110 (a)(2)] plan, with adequate provisions in each SIP to prohibit air pollutant emissions from within a State from:– Significantly contributing to nonattainment in any other State

– Interfering with maintenance of the NAAQS in any other State

• More stringent Ozone standard(s) will require:– Local solutions for sources in the violating (nonattainment) area,

– A regional component to address interstate transport,

– An analysis of the contribution from international sources that states are unable to control, and

– An understanding of how much natural sources like wildfire are contributing to high Ozone episodes.