2015 O3 NAAQS Transport SIP
Develop a consistent technical approach among the LADCO states for producing “Good Neighbor” SIPs for the 2015 ozone (O3) National Ambient Air Quality Standards (NAAQS).
Approach
In Attachment A of the March 2018 Transport memo EPA presented a series of options for addressing the four steps of the CSAPR O3 transport framework. EPA states in the memo that one of the guiding principles for evaluating whether a technical approach is appropriate for use in a transport analysis is that the “…alternative modeling is performed using a credible modeling system which includes “state-of-the-science” and “fit for purpose” models, inputs, and techniques that are relevant to the nature of the ozone problem.” This statement along with the flexibilities presented by EPA in the memo provide the states with multiple approaches for quantifying and reporting interstate O3 transport in their iSIPs.
LADCO, in coordination with the member state air agencies, must investigate the flexibilities presented by EPA, along with other technically defensible options, to find an approach that will be used in the technical support information that will accompany the 2015 O3 NAAQS iSIPs that the states will submit on October 1, 2018. The approach for the LADCO region in addressing the Good Neighbor SIP obligations of the member states follows:
- Understand the list of flexibilities presented by EPA; augment this list with additional flexibilities
- Submit a formal comment from LADCO on the EPA March 2018 memo
- Identify subgroups of the LADCO Project Team to perform analyses related to the alternative technical analyses with the goal of quantifying how the different approaches alter the interstate ozone contribution results
- Reach consensus among the LADCO states on the objective(s) of the iSIP technical plan. For example, is the objective to find a set of analyses that demonstrate the smallest future year contribution from the LADCO states to downwind receptors? Is the objective to highlight the influence of local emissions sources? International emissions?
- Evaluate the results of the different approaches and develop a protocol for how the LADCO states will collectively use common technical information to support their iSIPs
Documents
LADCO 2015 O3 NAAQS Transport Modeling Final Technical Support Document (13 Aug 2018)
LADCO 2015 O3 NAAQS Transport Modeling Draft TSD (31 Jul 2018) | Response to Comments
LADCO CAMx Transport Modeling Protocol | Response to Comments
2023 CAMx APCA Source-Receptor Linkages Excel Spreadsheet
U.S. EPA O3 Transport Resources
- U.S. EPA March 2018 Transport Memo and Supplemental Information
- U.S. EPA October 2017 Transport Memo and Supplemental Information
- U.S. EPA December 2016 Notice of Data Availability for Preliminary Interstate Ozone Transport Data
- U.S. EPA 2017 Final Cross State Air Pollution Rule (CSAPR) Update
LADCO 2015 O3 NAAQS Google Drive
Call Notes
Click the menus below to expand/collapse the notes for each date.
Agenda
- Roll Call
- Review action items from last O3 iSIP call
- Review the LADCO draft O3 iSIP TSD, LADCO results, and discuss any questions/comments from the states/EPA/FLM
- Review the LADCO Google Drive, including new technical analyses available from LADCO and others
- Define what will be needed by the states to support their iSIPs; review timelines, if available
- Identify subgroups for working on different aspects of the technical support resources needed for the October iSIPs
Notes
May Action Items
- States: provide feedback to LADCO on the timing of the O3 iSIP process, and information on what will be needed from LADCO to support the process at the states; status: still seeking information
- States: identify members of the O3 subgroup; status: some feedback received
- LADCO+States: design tasks/analyses for the O3 subgroup; status: needs work
Review LADCO draft O3 iSIP TSD
- Zac walked the group through the document
- LADCO requesting comments back by June 20, 5:00 Central; use the response-to-comments form;
- LADCO will send responses by June 22, and send out the draft final document to the states by June 27; these deadlines are important to accommodate MPCA SIP schedule
- LADCO modeling results in zero NAA’s in 2023, just 4 maintenance areas, including Sheboygan – Kohler Andre.
- Question about model performance and RRFs; how will the fact that the LADCO runs are biased low in the base year relative to the obs, and lower than the EPA run for the 2023 projection influence the RRFs? LADCO explained that the design of the RRF is to somewhat normalize model performance issues by creating a platform that is used in a relative rather than an absolute sense; the lower projections from the LADCO run relative to EPA means that the RRFs will be lower for the LADCO run (i.e., greater reductions) then the EPA RRFs for sites in the midwest and east
- Question about the plausibility of the LADCO modeling results; given how small a piece of the national inventory EGUs are, is it even feasible that differences in the EGU emissions result in up to 2 ppb changes in the future DVs? LADCO responded that the summaries of the EGU emissions differences in the TSD are at a very high level and don’t reflect finer temporal and spatial gradients in the data; these fine gradients will produce larger differences between the EPA and LADCO emissions that will certainly have larger hourly/daily impacts on the projected air quality; to better understand these results,
- LADCO and states need to look in more detail at the unit level differences in the EGU inventory on critical days in the DV calculations (top ten model/obs days) to see where/when the emissions are having the greatest impact
- LADCO notes that using 2011 as the base year will result in big reductions to 2023 due to the dramatic changes in the EGU emissions between 2011 and 2016; with a 2016-based inventory, the RRFs won’t be as low and so the relative differences between the base and future years won’t be as dramatic; states need to be prepared that if they are bumped up and attainment demonstrations are required for the 2015 O3 NAAQS, the projection modeling likely won’t look as dramatic in terms of reductions in projected O3
- What do the states do now given that several modeling studies show attainment? Do the states need to do anything else in their iSIPs? Do they need to calculate linkages between sources and receptors for attainment receptors? Do they need to pursue emissions reductions? EPA R5 commented that these are questions that should be addressing during national calls with EPA
Review the LADCO Google Drive
LADCO showed the different drive folders (from the README in that main Google Drive folder):
2011EN Benchmark
Model Performance Evaluation (MPE) plots showing the LADCO 2011EN CAMx modeling compared to the EPA 2011EN simulation; demonstration of LADCO’s ability to reproduce the EPA’s results and thus justify our use of their future year modeling platform for O3 SIP applications. Subdirectories include different types of plots for model-to-model and model-to-obs comparisons
2023 CAMx APCA
LADCO 2023 CAMx modeling results. The Plots directory includes different types of plots displaying the LADCO concentration and source apportionment results; and for comparing the LADCO 2023 simulation with the EPA 2023EN simulation. The Plots/Tileplots directory includes daily maximum concentration plots (avrg_png) and daily maximum tracer plots (sa_png) for the LADCO and EPA simulations. The Tileplots directory also includes a diff_2023en directory with difference plots (LADCO – EPA) comparing daily max CAMx concentrations
Data
Data files used to support the LADCO 2015 O3 NAAQS Good Neighbor SIP TSD. Files include site specific design values and contribution tables for the different analyses completed by LADCO
Documents
Documents library with reports, presentations, and spreadsheets of different O3 NAAQS-related analyses; see the README in this directory for brief descriptions of the files
Emissions
Plots and tables summarizing the emissions used in the LADCO 2023 simulations
Plots
Files of graphics used in the LADCO TSD, including bubble plots of DVFs and RRFs and tracer tile plots
Define what will be needed by the states to support their iSIPs
- IL is interested in the significance threshold of 1 ppb instead of 1% of the NAAQS; LADCO showed the table in the TSD and how by using 1 ppb, IL is only linked to receptors in the LADCO region; what will SIP language look like to justify using 1 ppb as the threshold, instead of 1%?
- IN is focusing on the EGU emissions, digging into the emissions at individual units in the ERTAC 2.7 inventory, looking at the controls at the units
- The modeling does not represent a commitment to an emissions level, it represents a commitment to a program; in this case, for EGUs it’s CSAPR
- IN will send out their iSIP for comment in August
- IL is still trying to figure out what they will be submitting
- MN is looking to get their final iSIP submitted by July 9; need a draft final iSIP by the end of June.
Identify subgroups for working on different aspects of the technical support
- Given that we have analyses from more than one modeling study projecting that we will only have maintenance in 2023 (no NAAs) in the East, focus of the analysis should be on figuring out how best to define maintenance; states commented that they are not comfortable with EPA’s current definition of interfering with maintenance; action item for CSAPR step 1 subgroup to convene and explore alternatives to defining maintenance and interference
- How else to define/quantify transport? CSAPR step 2 subgroup to explore alternatives for this issue
- What is the time frame for permanent and enforceable measures? When do these need to be implemented and when do their impacts need to be seen? More clarification from EPA needed on CSAPR step 4
Action Items
- All: Meet more regularly, each Monday at 2:00 Central; Zac to update calendar appt
- Zac: send MOG webinar information to group
- Zac: send EPA transport analysis slides to group
- Mathew: send additional analyses on using historical obs distributions for identifying maintenance
Agenda
- Review the scope of this group, define our objectives
- Review presentation from IDEM
- Discuss other ideas and agenda/schedule for next call
Notes
Schedule Update
Plan to meet weekly on Mondays @ 2:00 Central; Zac to update calendar
Review the scope of this group, define our objectives
Monthly meeting of a group of LADCO states to investigate options for CSAPR Step 1 in the 2015 O3 NAAQS transport SIP analysis. There are three areas that EPA lists as having potential for flexibilities in this area:
1) ID maintenance receptors
2) Consideration of downwind air quality context
3) Consideration of model performance
One of the areas that we’ve discussed looking into is how maintenance is defined, and what it means to interfere with maintenance. We can look at EPA’s definition and then brainstorm on alternatives to identifying vulnerable receptors and how to quantify interference with these receptors.
Here are a couple of questions to consider.
- Is there an alternative to use the Maximum DV to define maintenance?
- Would a monitor still be considered maintenance if it doesn’t show high values during ozone conducive conditions?
- How could trends in past observations factor into the definition of maintenance?
- Could model sensitivity to changes in emissions be a factor in the definition of maintenance?
- In terms of interference, does the monitor have more sensitivity to changes in local emissions than transported ozone?
While there are a few directions that we can go with CSAPR Step 1, we want to focus on maintenance because there are a lot of questions around its definition and what it means to interfere with maintenance
Review presentation from IDEM
- Modeling RRF applied to highest 3-year in the DV base for forecasting; in the current modeling (2011-based) 2011 and 2012 are back to back high ozone years; does including the highest years, which may also be historically high and represent anomalies, bias the projections high? Is there a way to eliminate anomalies in the maintenance calculation?
- In looking at air quality trends, think of how the O3 season data has changed over time; in IN distribution curve is looking like more of a normal curve, rather than showing a high concentration tail
- Reviewed data to look for a Gaussian (normal) Distribution, as more representative of an average condition
- In the 5-year base, take the three years with the most normal distribution, mix years rather than use consecutive years
- Gaussian is judged visually using `10, `12, `13; suggestion to should shift to statistical normality test, rather than visual
- Q: Why is normal more representative for interfering with maintenance? Aren’t we just looking at identifying maintenance, why is a normal distribution better for identifying the max of the 3 years?
- A: trying to capture representative, rather than anomalous, trends in the observations in order to use representative data for forecasting
Because we’ve observed a trend toward normality in the obs, it would be appropriate to use this for maintenance demos
- A: trying to capture representative, rather than anomalous, trends in the observations in order to use representative data for forecasting
- Q: What if the trends at a monitor are not showing normality? What if they’re showing a change toward a low concentration tail? Or continued trends with a high tail?
- Q: Would this only be applied to the maintenance monitors that were identified using the EPA methods, or replace it for all of the monitors?
- Initially thought we would apply it to all monitors
- Need to develop software to do this because the development and selection of a distribution curve is a monitor-specific exercise; it would be labor intensive to do this for every monitor
- Will focus on the persistent high ozone monitors first
- Underlying assumption would need to be supported by statistical analysis; can’t appear to be cherry-picking low historical years
- Needs to be applied at individual monitors
Discuss other ideas and agenda/schedule for next call
- Maximum of highest 3 year seems to be more stringent than using 5-year average; why is EPA using this for maintenance? May have to do with using NA test on the 5-year weighted average, with risk of interfering, the test wants to look at worst case scenario; argument for both ways (more vs less stringent), but still not sure why the maintenance test is more stringent
- OH Started to think about looking at how the states that have been defined as having maintenance problems are addressing it in their contingency plans; few contingency plans defined it as one year at the standard, which is more stringent than 3 year average attainment test; also looked at straight 5 year average, rather than weighted 5-year; dampens impact of high year; could we also look at the median instead of the mean
- Alt attainment test: need to account for variability in met and emissions; used a year that was conducive to high ozone (could be worse than actual), need to then account for variability in emissions; use a sensitivity run to change projections that shows that even if the emissions don’t change as much as projecting, still show attainment at the monitors
- Could we eliminate outliers? Are the already accounted for in the 8-hour standard; this can’t be arbitrary
- Norm Possiel (EPA) presentation on analysis of ozone trends and relationship to interstate transport
- Shows that recent obs trends in the Midwest and NE may be pointing to ozone as being more of local than regional problem
- After ID maint receptors, use the memo to argue that maint issues may not be the result of LADCO states
- Memo is more applicable to linkages than definition of maint.
- Use in step 3 to show that transported emissions are not as impactful, and coupled with decline emissions trends
Next steps
- All listen in on the MOG call on Monday (7/9)
- Meet again on Tuesday 7/17 at 2:00 Central
- Matt to send additional analyses on using historical obs distributions for identifying maintenance
- Action: calculate 2023 using 2011-2013 DVs as base (with EPA and LADCO modeling), instead of max of 5 years
- Produce revised TSD
- Add in sector analysis
- Look at stats distribution
Action Items
- LADCO: send along updated analysis from our 2023 modeling as they become available
- EPA R5: follow up on EPA call regarding the flexibilities in the March 2018 EPA memo
Agenda
- Roll Call
- Review action items from last O3 iSIP call
- Update on LADCO Modeling
- Review state iSIP timelines
- CSAPR flexibilities subroup updates
Notes
June Action Items
- States: send comments on LADCO TSD by June 20; Status: comments received from 3 states
- LADCO: send a draft final version of the TSD back to states by June 27; Status: done on June 29
- States: send LADCO their thoughts on their timing for the iSIPs (MN, IN, and IL have responded); and what they think will be needed from LADCO beyond this TSD; Status: discuss on this call
- CSAPR Step 1 Subgroup (Kenney, Beekman, Hollinger, LADCO): convene to explore alternative definitions of maintenance and interference; Status: scheduled and met on July 2; sat in on MOG call on July 9
- CSAPR Step 2 Subgroup (Kaloz, Hollinger, Welch, LADCO): convene to explore what, if any, alternative analyses could be used for quantifying O3 transport; Status: Cancelled the stand-alone group and will meet concurrently with Subgroup 1
- LADCO: get clarification from EPA on CSAPR Step 4, what are the time frames?; Status: Zac to follow up with EPA R5 on this question
Update on LADCO Modeling
- Error in the configuration of wet deposition; likely the cause of higher PM2.5 in the LADCO run relative to the EPA run
- Restarted the LADCO run and it will finish next week
- Sector Source Apportionment run is also running, it will be done this week
- We will update the analyses and TSD to be ready by the end of July; results will be presented as they become available
Review state iSIP timelines
- MPCA: June
- IDEM: Late July; looking for information before the end of July; reverted to EPA modeling and will incorporate LADCO results as we can
- WI DNR: technical work, qualitative statements on satisfying 110a2d requirements; not relying on specific outcomes from specific model runs;
- IL EPA: Late July for technical information
- OH EPA: Plan on having a document for internal review done by end of July, have to be out for public comment in mid-August; weight of evidence discussion of how they addressed their contribution
- MI DEQ: Same as OH, end of July, out for comment by mid-August
- IL: understood that EPA would have a call with states to further discuss flexibilities document; has anyone heard more about this? No dates have been set, beyond the proposal in May;
- EPA R5: we were actively talking to affected industries and would hold a call in mid-July to discuss the flexibilities document; states looking for guidance on what they would accept or not accept; Jenny to follow up with headquarters on this item; only thing we know is what’s listed in the flexibilities document: if states use 1 ppb rather than 1% threshold, need to have technical justification (e.g., SIL);
CSAPR flexibilities subgroup updates
- Looking defining maintenance
- MI: UAF file behind the modeling, units designated for retirement in 2023? Units are retired January 1, 2023
- LADCO: Yes, we can dig into specific units by request
- MI: MOG presentation, thoughts on what everyone heard, what stood out: reliance on international impacts on BCs, how they looked at maintenance and 10 years of emissions decreases for maintenance;
- OH doesn’t agree with looking at the 10 year period (redesign requirements) of emissions reductions; seems appropriate for the state with the monitor but not upwind states; should be looking at the point in time when maintenance is measured; would look out to 2023, not byond (i.e., 10 years) unless for weight of evidence
- IN: international transport, minimal state level contributions relative to international transport; in contrast to state level sources
- Helpful from weight of evidence if it’s coming from sectors; LADCO will provide information on the sectors, but not state and sector tags; we don’t have the time to do this run
Agenda
- Review the scope of this group, combining CSAPR step 1 and 2 into a single group
- Discussion on MOG presentation from 7/9
- Discuss LADCO modeling
- Brainstorm on technical questions related O3 transport: e.g., IDEM historical distributions of O3 obs for defining maintenance; emissions trends and maintenance
Last Call (July 2) Action Items
- All: Meet more regularly, each Monday at 2:00 Central; Zac to update calendar appt.
- Zac: send MOG webinar information to group (see attached)
- Zac: send EPA transport analysis slides to group (see attached)
- Mathew: send additional analyses on using historical obs distributions for identifying maintenance
Notes
Review the scope of this group, combining CSAPR step 1 and 2 into a single group
Step 1
1) ID maintenance receptors
2) Consideration of downwind air quality context
3) Consideration of model performance
One of the areas that we’ve discussed looking into is how maintenance is defined, and what it means to interfere with maintenance. We can look at EPA’s definition and then brainstorm on alternatives to identifying vulnerable receptors and how to quantify interference with these receptors.
Here are a couple of questions to consider.
- Is there an alternative to use the Maximum DV to define maintenance?
- Would a monitor still be considered maintenance if it doesn’t show high values during ozone conducive conditions?
- How could trends in past observations factor into the definition of maintenance?
- Could model sensitivity to changes in emissions be a factor in the definition of maintenance?
- In terms of interference, does the monitor have more sensitivity to changes in local emissions than transported ozone?
Step 2
1) Considerations in determining contributions
2) Considerations in evaluating contributions
One of the areas that we’ve discussed looking into is the contribution thresholds, the 1% vs 1 ppb threshold. This is pretty easy to do but beyond this in the current modeling runs, here are few questions to consider. Please suggest others:
- Quantify collective contributions and calculate a red-line contribution for each source, i.e., how much is a source contributing to the NAAQS violation (increment of ozone above the standard)?
- Do the collective contributions point to a local or transport issue?
- Could different thresholds be applied for different source regions?
- Do we look at inventory sectors as sources instead of geographic regions?
Discussion on MOG presentation from 7/9
- 4km modeling
- 1% vs 1 ppb
- 10 year emissions reduction
- International emissions/transport
- Proportional contributions (red lines)
Brainstorm on technical questions related O3 transport
- IDEM historical distributions of O3 obs for defining maintenance; emissions trends and maintenance
- Explore multi-year frequencies, via probability distribution functions concentrations at monitors; is there a pattern that distinguishes non-attainment, attainment, and maintenance?
Action Items
- LADCO: contact TX about comments they’ve received on their iSIP
- LADCO: contact EPA region 5 about 2011-13 maintenance approach
- IN: share back trajectories when they’re ready
- LADCO: send annual total unit emissions for small EGUs
- LADCO: send 2011 and 2023 emissions sector annual totals
Notes
- Holly asked if we will create the Bias Filtered DV forecasts on the no-water base year DVs;
- LADCO will create these if Holly requests them, she’s not sure at this point. Since it’s a lot of work, LADCO will wait for the specific request if they are, in fact, needed
- Reviewed the maintenance forecasts based on the 2011-13 DVs; looked at the water, no water, and bias filtered results; Matt asked what happens if a monitor is forecast to be nonattainment, but this method forecasts no maintenance?
- This is the case for the Suffolk, NY and Harford, MD monitors
- Need to check what TX did for this case
Action: Zac to contact TX and EPA R5 regarding using this approach for maintenance - Check in on Thursday’s iSIP flexibility call with EPA
- Back trajectories
- IN is doing back trajectory analysis for monitors in the NE
- 2015-17 data on high ozone days
- Will share results with the group
- Red line analysis
- Holly reviewed why home states are not typically included in this analysis, found the DC Circuit Court ruled that the home state is only included if the state is nonattainment on its own (without contributions from other states)
- This decision was remanded by the supreme court
- States need to avoid over-control
- OH and IN will use the red line analysis to show how small the state responsibilities are, with the largest reduction at 0.9 ppb total O3 at Suffolk, NY
- Emissions
- OH requesting small EGU emissions annual/O3 season totals by unit for small muni EGUs
- Zac to schedule Mark to have a call with Holly on Monday 7/30 to figure this out
- Zac to pull EGU annual and O3 season totals and send to Holly; looking for annual/seasonal emissions totals by sector for 2011 and 2023
- Keep everyone in the loop on emissions discussions
- EPA receiving formal and draft submittals
- Washington is being proposed for approval
- Flexibilities
- Comments
- ID Maintenance Receptors
- Commentators indicated that sites should only be if current and projected above
- Current attainment = not maintenance
- Use most recent DV instead of max of 5 year
- Omit monitors with DV < standard while there was also conducive met
- Max DV not legally sound
- Screening Threshold
- 1% threshold is arbitrary and 1 ppb should be used
- 0.7 ppb threshold is less than measurement sens of instruments
- Appendix U requires hourly avg to the 3rd decimal place, truncated, 0.07 ppb would be zero?
- Geographic variability should considered in selecting threshold
- Int’l Emissions Contributions
- Recommend apply analysis if receptors would be NA or maint but for contribution of int’l emissions; need to account for Can/Mex and US
- Expand photochemical model domain to include all of the Can/Mex
- Quant if non-US anthro emission will aid states in accounting for impacts of emissions
- EPA should estimate in’l contributions from dirty source outside of the US, i.e., uncontrolled power and mobile sources
- Legal arguments for addressing and why covered by CAA
- Upwind states not absolved for making progress in the face of impacts from int’l emissions
- 179b address int’l emissions, no need for EPA to rewrite under 110b
- How will EPA finalize the flexibilities guidance? Rulemaking?
- EPA may create a memo, but looking for feedback from the states; looking for what and how on these issues; response to comments? No, follow on will help states get some clarity, but not a formal process; states are already taking advantage of these flexibilities; resolution will play out in actions on individual SIPs
- What states are already being reviewed/approved?
- Once EPA receives a SIP, it’s public knowledge; EPA can provide updates through MJOs, calls
- For states interested, look at what other states are doing by their comment and rulemaking websites; EPA’s information is not always up to date
- What is the turn around on additional documents from EPA?
- EPA needs to know what these are first, before they can commit to timing; will try to be timely
- EPA response on maintenance
- There are some good ideas, and a need for supporting information, justification for the flexibility in the plan
- Will be referring to different steps, based on EPA framework; could be other more tailored frameworks
- Step 1. Maint receptors
- Eliminate site as maint if it’s currently measuring clean data and add’l supporting information (met trends, obs O3 trends, emissions trends)
- If SIPs don’t include justification for why the state thinks the clean data will continue, it will be hard to approve (clean data measured during conducive met conditions)
- Q (KY): what if state is showing downward trend in emissions but downwind receptors are showing increasing O3?
- Will need to work with the state on the data; (MD) upwind states need to look at daily emissions trends and not O3 season avg trends, is that right? EPA hasn’t considering the temporal averaging times; if a state shows declining daily and seasonal trends would be most compelling; there may be cases where the trends (daily vs seasonal) conflict; forward looking trends? Yes, there is a historical component, but also need to look into the future (using seasonal projection), if there are daily limits, these should be reflected in the future projections
- EPA response on thresholds
- Inclined to say that 1 ppb is acceptable, based on analysis of collective upwind contributions; is a reasonable flexibilities;
- Q (GA): what is the collective upwind contribution work?
- EPA analysis looking at 2023 modeling results, looked at different contribution thresholds, haven’t shared with states yet, overall amount of collective contributions between 1% and 1 ppb are similar (captures same collective contributions); 1.5 and 2 ppb showed different collective contributions (degradation)
- Int’l Emissions/contributions
- Appropriate to consider in step 3, multi factor assessment of cost and air quality
Rely on collective upwind contribution, look at total US anthro and ID receptors where the amount of upwind from anthro US is a small portion relative to int’l sources; won’t apply to most receptors - Info in March 2018 memo on this, see DV spreadsheet that identifies the amount of collective contribution, including
- Q (DE): does EPA have an idea of the % of int’l contribution, what’s the threshold percentage for providing relief to US contributors?
- Don’t have a particular threshold, informed by the March 2018 analysis where receptor is dominated by non-US sources, analysis is to look at the receptor and the extent to which it’s subject to anthro on collective basis, see converse of all US, what’s left over after all US sources; look at regional differences in non-US, there is no bright line for contribution, will need to have dialogue with EPA
- Q (OTC) How will exceptional events guidance be considered?
- It’s a narrow set of things, but looking at alternative paths guidance for considering influences that are not the traditional EE, ought to be a way to flag data other than the EE rule, more to come in the fall with EE guidance
- How to document?
- Observed some violating monitors that read higher than surrounding monitors (land-water interface), Sheboygan between two attaining monitors; how do we consider this? Can we change the domain? Up to states to use modeling to ID if it’s a regional or local problem, regional problems also lend to local problems; states should work with MJOs and others, looking at fine scale modeling; do states need add’l guidance, what is helpful to provide, timely or detailed? Need to communicate to states this in some way as their developing their SIPs
- Appropriate to consider in step 3, multi factor assessment of cost and air quality
- Send additional questions to Norm
- Will states have more flexibilities if their only contributing to a main monitor? Need additional discussion about this
- MD: Missing from this process is the collaboration between upwind and downwind states; upwind states should know if the downwind state is going to challenge the EPA guidance, this needs to make it into the regulatory process
- Send out smaller, quick memos to fold in guidance as their writing their SIPs
Agenda
- Review action items from last call (see below)
- Discuss EPA flexibilities call last week (LADCO notes)
- Discuss LADCO TSD and remaining needs from the states, including emissions summaries
- Brainstorm on technical questions related O3 transport: e.g., IDEM historical distributions of O3 obs for defining maintenance; emissions trends and maintenance
- Next calls
Last Call (July 23) Action Items
- LADCO: contact TX about comments they’ve received on their iSIP
- LADCO: contact EPA region 5 about 2011-13 maintenance approach
- IN: share back trajectories when they’re ready
- LADCO: send annual total unit emissions for small EGUs
- LADCO: send 2011 and 2023 emissions sector annual totals
Notes
Discuss EPA flexibilities call last week (LADCO notes)
- Get contribution threshold spreadsheets from Norm
- Ask air directors about pressing EPA guidance
Discuss LADCO iSIP and remaining needs from the states, including emissions summaries
- Bias filtering can be done in different ways; include information on high bias 60, 65, top 10 days; do we want to retain this section in the document? Single bullet in the discussion
- Need to balance policy and science; need to meet policy requirements vs getting into situation where we give the bullet to the other side; what goes into the document needs to be agreed on by the entire group; give a larger picture of the bias discussion, some monitors are high, some are low
- May be more weight of evidence that contributions by individual states may not matter, take the information with a grain of salt; says the opposite of what NE states may say
- May not need to include that we’re doing additional work beyond this document
Brainstorm on technical questions related O3 transport
Action Items
- States: send comments on LADCO TSD by June 20
- LADCO: send out final TSD, by Monday August 13
Agenda
- Roll Call
- Review action items from last O3 iSIP call
- Update on LADCO TSD: review current draft, draft vs final
- O3 iSIP group wrap up?
Notes
July Action Items
- LADCO: send along updated analyses from our 2023 modeling as they become available; Status: done, see TSD version August 7, 2018
- EPA R5: follow up on EPA call regarding the flexibilities in the March 2018 EPA memo; Status: done, call held July 26
Update on LADCO TSD: review current draft, draft vs final
- Friday 5:00 Central as a deadline for gathering comments on the current LADCO TSD
- Final or Draft?
- OH: Have always made the TSDs final, should not be draft before these go out for comment; PDF will be attached to the TSDs and LADCO will also include on the website document archive
- Once on the LADCO website, it’s public
- If LADCO receives comments and they are controversial, alert the states
- What are the O3 tracer inventory sector plots?
- These show the seasonal maximum tracer concentrations; represent the maximum possible extent of influence, more qualitative than quantitative
- Is there a concerted effort to evaluation the different inventory sectors?
- Yes the National Inventory Collaborative is using workgroups of state/federal/MJO staff to look closely at the inventories and emissions projections.
O3 iSIP group wrap up?
- We will wrap this group up and go back to the one project team meeting/month
- Discussion on 2016 modeling,