Science and Technical Support Work Group Face-to-Face Meeting

October 28-29, 1996

Dallas Grand Hotel

Dallas, Texas

The Science and Technical Support Work Group (STSWG) held a face-to-face meeting on October 28-29 at the Dallas Grand Hotel in Dallas, Texas. A list of attendees and a summary of the meeting follows.

Monday, October 28, 1996

Work Group Participants

Name	Affiliation

Tom Helms, Co-Chair	U.S. EPA

Harvey Jeffries, Co-Chair	UNC - Chapel Hill

David Chock	Ford Motor Company

John Cabaniss	AIAM

Glenn Cass	Cal Tech

Bruce Hill	Appalachian Mountain Club

Dave McNeill	Utah DEQ

S.T. Rao	New York ARB

Mark Scruggs	DOI

Dan Weiss	Cinergy Corporation

Steve Ziman	Chevron Corporation

Leon Outlaw (for Jay Hudson)	Santee-Cooper

Work Group Members Not Participating

Jeff West	NARSTO

Diana Andrews	Kentucky

John Core	WESTAR

Ellis Cowling	SOS

Kirit Chaudhri	Virginia DEQ

Rich Poirot	Vermont

Non-Work Group Participants

Bob Wayland, Fred Vukovich, SAIC; Mike Teague, Hunton and Williams; Pradeep Saxena, EPRI; Neil Frank,EPA/MQAG; Bob Judge, EPA/Region I; Jim Yarbrough, James Davis, EPA/Region VI; Bill Johnson and David Sanders, U.S. EPA/OPSG; Carey Fitzmaurice, Guy Donaldson, Mark Satho, Quang Nguyen EPA; Marvin Lowry, GA EPD; Cyril Durrenberger, Dick Karp, Dave Harper, Mike Fishburn, Jim Smith, James Red, TNRCC; Bob Imhoff, TVA; Joe Belanger, CT DEP; Bennett Farrior, LA DEQ; Don Blumnehtal, STI; John Elston, NJ.

Summary of Meeting

Harvey Jeffries welcomed everyone to the Science and Technical Support Work Group (STSWG) meeting. He noted that during this meeting, the Work Group would discuss some of the issue papers developed by other FACA Subcommittee Work Groups. Mr. Jeffries introduced the first presenter, Diana Andrews.

Monitoring Incentives, Diana Andrews

In Ms. Andrews absence, Harvey Jeffries presented a summary (prepared Ms. Andrews) of the Monitoring Incentives issue paper that was originally developed by the Base Program Analyses and Policies (BPAP) Work Group. Ms. Andrews identified the need to develop an air quality monitoring network that is sufficient to generate the scientific information needed to support the new National Ambient Air Quality Standards (NAAQS).

Glenn Cass stated that he did not feel that additional monitoring was necessary. However, there was a need to analyze data that has already been collected.

Steve Ziman added that it was not clear to him that the current monitoring network is doing the job that it was intended to do.

Glen Cass responded that he felt very uncomfortable with any form of a statement that advocates that more monitoring is better. He suggested that we need to spend our resources on issues of a more technical nature.

Harvey Jeffries asked Mr. Cass to summarize his concerns in a couple of concise statements that he could take to the full FACA Subcommittee tomorrow.

Mr. Cass stated that we need an adequate monitoring system to resolve the temporal and spatial scales at hand; however, we do not simply need to put out more monitors. This, will not solve our problem.

Steve Ziman acknowledged that, in theory, he agrees with Mr. Cass and that he was essentially saying the same thing. However, Mr. Ziman cautioned against any underlying hint of compliance with any monitoring proposal.

Harvey Jeffries stated that we must be careful here not to remove the incentives for monitoring. He noted that we are attempting to increase our ability to detect violations and the areas affected by such violations. However, we must be careful not to limit ourselves. He added that monitoring will not solve the issue alone, rather, some modeling and some data analysis must be incorporated into the program.

S.T. Rao suggested that from the science perspective, this assumes that the current monitoring network is adequate. Thus, he added, from a science standpoint, we should do an analysis of the existing data, and determine whether it is adequate to capture the spatial and temporal variability in both ozone and fine particulate matter (PM). For example, the guidance document for ozone monitors was developed in the 1970s and is obviously, not representative of our current knowledge. He stated that we simply need sufficient density of monitors to resolve the scales of interest - which does not necessarily mean more monitors.

Steve Ziman suggested that perhaps this issue paper should be sent back to the original author and attempt to remove some of this "compliance oriented" approach. He added that he thought this paper should be given more thought.

Harvey Jeffries asked if the Work Group recommended that this paper be sent back to the original author.

Tom Helms suggested that there should be a group reaction.

S.T. Rao stated that monitoring data must be shown to be representative, or the network must be reorganized.

Bruce Hill gave no comments on the issue.

John Cabaniss offered no comments on the issue.

Harvey Jeffries stated that there are a good number of monitors which are put out and removed after 2 years to prevent information collected from being used for regulatory purposes. He added that there are two basic needs for the monitoring networks: 1) research and 2) compliance. The second need is where this "disincentive to monitor" comes into play. He recommended that this paper go back to the author and ask the author to incorporate this "double concept" into the monitoring paper.

Cyril Durrenbrger, State of Texas, commented that he wants to remove the disincentive for monitoring.

S.T. Rao noted that we should simply adopt the Area of Influence (AOI) and Area of Violation (AOV) concepts which would do away with the disincentive to monitor.

Steve Ziman asked what are we trying to accomplish with this monitoring network? He noted that it appears as if we are only dealing with the compliance side of this issue. For example, we have seen areas in Northern California go in and out of attainment and are left with the dilemma of trying to do a compliance demonstration when the majority of the data do not show nonattainment. Thus, State and local districts have no incentive to provide this additional monitoring.

Dave McNeill commented that the STSWG needs to stay away from policy. He agreed with S.T. Rao and Glen Cass that the STSWG needs to review our current network and say what the worth of this system is. He added that if it is indeed worthless, then we need to state as scientists how we would improve the network and stay away from the policy.

Glen Cass agreed with S.T. Rao. The Scientific Advisory Panel should tell people that we need a national air monitoring network that has been evaluated and tested. Mr. Cass added that we need this for determining compliance, background concentrations, progress over time at a site, population exposure at a site and even for model validation efforts. Thus, we need to develop siting criteria which will meet these objectives as well as possible, subject to the given budget constraints. Given this budget constraint, then we would proceed as best as possible to meet these objectives.

Steve Ziman commented that we collect data and collect data, but there should be a requirement in this document that data must be analyzed and used to refine this procedure.

Regional Haze, Donna Lamb and Mark Scruggs

Harvey Jeffries stated that the most notable improvement in this issue paper is the moving of science directly to the front of the issue paper.

Donna Lamb stated that in dealing with regional haze, there are a lot of issues which need to be addressed prior to getting to the guts of the regional haze issue. She added that a lot of these issues are linked to differences between the east and the west. She said that currently we know more about regional haze in the west than we do in the east. She stated that the group developing the Regional Haze issue paper looked at a lot of IMPROVE network data and reports. The group concentrated some on the east but not at the expense of downplaying the experience gained in the west.

Ms. Lamb said that her group generated some basic difference between east and west (see page 3 of issue paper, Table 1). These are:

:

-	Visual range in the east is 25% of that in the west.

-	Reduction of SOx by 10% does not drastically affect the visual range issue.

-	Sulfate contribution of total extinction much higher in the east (70%) versus the west (30%).

Harvey Jeffries questioned the statement on page 3, paragraph 2, "... is there a clear scientific explanation for RH."? He asked if this was true.

Donna Lamb noted that, essentially, we are looking at three issues here: monitoring, modeling, and emissions inventories. We are looking at the monitoring; how well does the monitoring network classify the Class I areas in the east and the west (e.g. see Table 2 in the issue paper). However, if you go to modeling, you need to look at the kinds of models which have been run for the Title IV Program, to look at the progress with respect to Title IV in the eastern United States. These model runs dealt with the acid deposition issues as well as the visibility issues. Thus, if you look at the east, the modeling in part has already been done as part of Title IV. Finally, we need to look at the emissions inventory information.

Steve Ziman suggested that monitoring data is meaningless if we do not analyze it. He stated that it is difficult to make policy decisions when we don't have an understanding of the basic parameters associated with these issues.

Mark Scruggs explained how this paper evolved. He noted that it was originally part of the integration and implementation issue paper but there were key differences. First, regional haze is not a NAAQS. Thus, reasonable progress became an issue very early. Second, the need for speciation was determined. We were looking at a cause and effect type situation. We identified two deficiencies in the monitoring network; basically, there are not enough monitors (and, they are generally not in the right places), and the network is predominantly a rural network. Finally, we tried to present some basic results and we got off on this east-west issue and the seasonality issue. The desire for integration of ozone, PM, and regional haze at the level of detail that STSWG has been discussing will require a very specific and specialized model. Thus, these are the problems and they are all driven by the problems of integration (e.g. ozone, PM and regional haze). The National Research Committee (of the National Academy of Sciences) was asked to evaluate the integration of regional programs. They were simply looking at regional haze. It is thus out of context to remove this statement, and apply it to our mission here.

Glen Cass stated that basically, the folks on the National Research Committee felt that there was enough knowledge available at the time to start improving visibility conditions through emissions reductions. Mr. Cass concurred with this assessment. The heart of the committee's recommendation was to develop databases and model results that could be used to address this issue on a regional basis. It was not intended to be a political statement with which to drive public policy.

Steve Ziman commented that is fine but these things simply do not exist in most parts of the country.

Harvey Jeffries asked Mr. Cass if what he was saying was there is not a fundamental gap in the knowledge base.

Glen Cass responded that he would not say that there is a scientific gap, rather that there is an implementation issue here.

Donna Lamb stated that the regional haze issue will be presented to the FACA Subcommittee on Wednesday. She noted that towards the end of the issue paper there is a section which defines the objectives with respect to the Class I areas and the remainder of the United States.

Steve Ziman commented that the issue here is the data that is requisite for carrying out these recommendations. He added that for the most part, these data do not currently exist and the data that do exist are simply insufficient to assign culpability to a region or industrial group based on any shape or form of modeling. Thus, you can set your goals, but we are unable to enunciate what these goals translate into in terms of an integrated ozone and PM program. He concluded that these things are simply not currently within the framework of what we can comprehend as reality.

Glenn Cass suggested that it is best to be trying to answer the right questions with a limited resource, than to be answering the wrong questions with a very sophisticated resource. Thus, he stated, the principle thing is to try an analyze the visibility issue for the nation on relatively large regional scales (i.e. regional haze). Mr. Cass added that the concept of "speciated rollbacks" in various parts of the country could be a viable alternative. However, one could take the alternate view of doing nothing until the absolute results are conclusive.

Steve Ziman stated that with regards to speciation, seasonality, etc., the level of data available are simply not adequate to do a scientific analysis.

Donna Lamb commented that the important issue which is not really in the paper is if you look at the scattering coefficients, you get a different priority schedule on your emissions controls than if you simply address particulates with your controls. She guessed that if you looked at ozone precursors you would get a different prioritization schedule. Ms. Lamb stated that a long-term strategy for the entire United States is probably bogus, however, long-term regional approaches may be valid.

Dan Weiss felt that this statement was still wrapped in policy and needed to be adjusted. He noted that essentially this is saying that there are no scientific hurdles only roadblocks in the implementation (e.g. "The devil is in the details").

Economic Incentives, Joe Belanger and Steve Ziman

Joe Belanger, National and Regional Strategies(NRS) Work Group, began the presentation by noting several assumptions. First, regional strategies are going to be one of the concepts used in the AOI and AOV issues. Second, a sufficient command and control strategy will be in place to drive the system.

Joe Belanger said that input is needed from the STSWG to show NRSWG where the links to responsibility have to be in these trading programs. Also, he asked for the STSWG to help the group look at the size of these trading regions. He added from the policy side, my concern is that we let the reach for perfection cloud our view of simply doing something good. We simply want to reduce the cost of compliance to everyone. We have discussed the tradeoff between doing too much and allowing some imperfections in the system which we can live with in the trading program(s).

Steve Ziman suggested that in determining trades, we should not look at trade for trade but look at the region defined and then look at establishing market mechanisms which would achieve the desired goals at the lowest cost.

Joe Belanger commented that his group hasn't questioned whether the standard is achievable or not. They are simply evaluating control schemes relative to the associated market- based methodology.

Harvey Jeffries said that he can understand options A and B (e.g., page 2 of the issue paper). However, he did not understand how you mix mobile and point sources in a trade.

Joe Belanger responded that this is a valid argument, but I don't think it is addressable here today.

Harvey Jeffries added that he did not think the market "will play" in this particular arena.

Joe Belanger responded that it is simply a question of creating the value. The information here is public information, not private. He stated that you need a mechanism to turn this into a discrete number and there are programs designed to do this which are currently operational. He gave an example of a casino in Connecticut that has agreed to offset the emissions of their patrons by going to local sources (e.g., stationary sources) and getting the requisite reductions.

Harvey Jeffries said that this is where he had problems with options C and E. There is no trade-off between, for example, say low-level and elevated NOx. He added that he knew this trade-off is not equal.

Joe Belanger agreed. However, he added, in the air quality world there are preferred currencies. Obviously, in the casino example, we would prefer mobile emissions for mobile emissions. This statement in C was designed to do expressly that (e.g. do not trade low-level NOx for elevated NOx or wintertime emissions for summertime emissions). As for is a ton a ton everywhere? This has been brought-up in the Ozone Transport Assessment Group (OTAG) and Ozone Transport Commission (OTC). He noted the OTC agrees that it is imperfect but has generally agreed that a ton is a ton. The OTC has stated that these inadequacies will be made up in Phase 3.

Joe Belanger asked are we designing these programs as attainment programs, or are we trying to improve overall air quality? The OTC has decided that it is not an attainment strategy and has chosen to work towards improving air quality.

Harvey Jeffries asked if you need some underlying command and control to step in where the market-based approach fails.

Joe Belanger responded "absolutely." He added you will need some command and control "trimming" with any type of market-based trading program.

Steve Ziman said you will also have to make a policy decision as to what you are trying to control. He noted that some events occur relatively frequently while others occur quite infrequently.

Harvey Jeffries stated that the way this thing works, is once a political entity decides for a trade, then the "market" basically drives the remainder of the process.

Joe Belanger responded "yes." When you look at these programs, you have to look at the scientific effectiveness, and the ease with which they can be implemented.

Harvey Jeffries summarized the discussion by stating that essentially you're saying that there are reductions that only a market-based incentive program will produce and given the imperfections of the system, can be overlooked for the overall net benefit to the environment.

Dan Weiss asked how do you define "necessary pollutant reductions"?

Joe Belanger stated that essentially, it is a one-size fits all approach, following the necessary fine tuning. He added the trading program will be designed to fit the big picture, and then the fine-tuning will take place.

S.T. Rao commented that in designing such programs, we're not from a scientific standpoint suggesting that detailed modeling is required for every case study. Thus, we must underscore our position that the reductions are achievable and that the reductions are necessary for an improvement in local/regional air quality.

Steve Ziman added that we have a mechanism that was developed for the SO2 program.

Harvey Jeffries responded that the agreement to do this was a congressional action, and this is not what we're doing here. Mr. Jeffries asked how do you get them to do this outside of a congressional act?

Joe Belanger stated that the 11 OTC states (plus Washington, D.C.), have agreed to implement this program described in the issue paper, and it appears to be workable. People will use science to temper the equity issues down the road. The process will be iterative. The challenge is to determine where you need what in terms of reductions, and ways to reduce the costs of these reductions. That is really all the policy people want from the science people. He commented that he really did not think there will be "a nice clean system" up front. He suggested that we start with NOx and SOx and then expand into other, more complex trading issues.

Dan Weiss commented that the trades are not designed to reach attainment but that they are simply designed to show progress towards attainment. Mr. Weiss asked Mr. Belanger to clarify what he meant on page 2, Option A regarding backsliding.

Joe Belanger responded that it meant you should not be doing anything that would generate an adverse effect on the air quality of a region. Essentially, "let's not take any holidays on our way to attainment".

Ben Kenneke suggested that there are some choices as how the trading is used (e.g., whether it is blunt or sharp in focus). He added that the issue that trading does not deal with is who pays. If you use a blunt instrument, then everyone pays. However, if you are using the AOI/AOV approach, you still have to deal with the people in the AOI and the AOV still has to pay. Thus, the more you make it a blunt instrument to spread out the costs, the less effective the trading program becomes. Thus, trading does not solve the political issue of who pays.

Harvey Jeffries said that this sounds more like an economic/policy question, and not very scientific one.

Joe Belanger disagreed. He added that it did have scientific implications.

Institutional Mechanisms - S.T. Rao

S.T. Rao commented the new document dated October 1, 1996 contains a good deal more information on existing mechanisms. He noted from a science perspective, there are 3 issues: 1) the need to move away from the current concept of designating areas as nonattainment, and move toward the AOV/AOI approach, 2) the need to establish the regional compacts that will recognize the AOV/AOI approach, and 3) the need to provide dedicated funds to ensure that the data and tools are developed and properly analyzed and utilized. In accomplishing this, the tools and the data necessary to establish these concepts need to be developed. He identified the tools as the most important link here.

Dan Weiss asked what happens if you don't have the tools necessary to develop an integrated plan? Do you develop the tools first prior to developing the AOV/AOIs?

S.T. Rao responded "ideally yes, but the world is not ideal. You should take a good approach and allow yourself room to fine-tune as the tools are developed and the data are analyzed."

Dan Weiss argued the reverse approach from an economic standpoint.

S.T. Rao declined to comment on that statement because it was not scientific.

Harvey Jeffries asked if the institutions that exist in this paper are capable of functioning under AOV/AOI?

S.T. Rao gave the OTC as a workable example.

Harvey Jeffries said that this is not a good example, because it is mandated in law.

S.T. Rao stated that we will have to wait and see how OTAG does then. This is entirely a mechanism outside of the law. We should have our answer in 6-7 months. This paper is simply an evaluation of existing mechanisms it does not make recommendations for this process.

Harvey Jeffries suggested that this is not an institutional mechanisms issue paper - it is simply an overview of existing mechanisms. Mr. Jeffries said that he did not understand the requirement for "dedicated funding". He asked if the examples in this paper have this stipulation?

S.T. Rao responded "not totally." He noted that LADCO has provided/generated some funding for OTAG but that funding can also create problems.

*** BREAK ***

Options for designating PM-Fines Areas (written by Gary Blais, as designated by Joe Paisie)

Harvey Jeffries said the ratio method is not a very good approach for designating PM-fine areas. Only monitoring data can be used to designate an area as nonattainment. Thus, the only discussion that there should be is how many years it takes to do designations for PM-fines.

It was noted that the FACA Subcommittee recommends that a minimum of 2-years monitoring data be used to set designations. Mr. Jeffries asked where did this statement come from?

Neil Frank responded that typically a three-year period is required for designation and/or redesignation.

Harvey Jeffries commented that there is some precedence for sticking with the three-year period.

Dave McNeill asked how do you ratio this stuff?

Harvey Jeffries questioned the scientific basis of three years of data? He asked why don't we ask for 5 years?

Glen Cass commented that he thought everyone would agree that they would rather set the designation on real PM-fine data as opposed to using ratioed PM10 data. The question then becomes is 2 years of real PM-fine data adequate to determine the designations; or, should we simply use 3 years of ratioed PM10 data to determine the designations?

Dave McNeill suggested WESTAR would recommend that you collect data requisite of the standard. Thus, it makes no sense to start making redesignations without the proper amount of data being collected and analyzed. He added that if you want to do it with ratios, we could do it today.

Glen Cass asked what is the probability that you are likely to make a mistake on a monitoring site's designation, given that one year, two year, three years, etc. were used to define the designation. Obviously, four years is better than one, but how much are we willing to accept within an a reasonable margin of error.

Neil Frank responded that you have to make some assumptions here.

Steve Ziman commented that you also have to understand what's driving your designation process. Are you dealing with an annual exceedance or more frequent issue?

Harvey Jeffries noted that this argument would lend itself towards this "rolling method" (Option 6, pg 6 of the issue paper). This does suggest that you don't have enough data to classify everybody and thus you must collect data to complete the process.

Tom Helms asked "what's our punch line?"

Steve Ziman said that all we are talking about again is compliance. He added that something needs to be said about monitoring and the need to not be blind about the concept of monitoring and compliance.

Glenn Cass asked what is this AOI/AOV approach (Option 8), which is discussed on page 7? He stated that he would pull this issue out and consider it to be a follow-on issue.

Tom Helms commented that we have made some decisions. He summarized the decisions as: state that you have to have real data upon which to base your designations and the only area of concern really is how many years of data is enough.

Glenn Cass stated that there is enough real PM2.5 data around in various parts of the country that you could reasonably determine what is a borderline case, using this historical data.

New Development in the AOI Concept, S.T. Rao

Mr. Rao pointed out that the objective for this study is to determine the AOI for an AOV. The methods used include:

(1)	Trajectory-Cluster Analysis

(2)	Statistical Correlation Analysis of Spectrally-Decomposed Ambient Ozone Data

(3)	Photochemical Modeling Analysis.

S.T. Rao strongly suggested using the "weight of evidence" approach in determining the AOI/AOV approach. Mr. Rao discussed the role of atmospheric transport in ozone concentrations at the Whiteface Mountain. The following data sources/methodologies were used in evaluating transport at Whiteface Mountain:

NGM Met data

HY-SPLIT3 Back Trajectories

Dorling's Clustering Methods (Atmos. Env., 1992)

Cluster Segregated Ozone Data

Statistical analyses.

S.T. Rao asked how many days of back trajectories do you use? He noted that Rich Poirot in his OTAG work has used four (4) days. Mr. Rao noted that the HY-SPLIT3 Model is used in this study. It used a:

3-D mixed layer trajectory model

3-day back trajectories

5-year period.

Mr. Rao said Dorling's Clustering Methodology was applied to the trajectories. In general, 8 trajectories can capture the local climatology for the Whiteface Mountain. He added that these clusters segregate the data into synoptic patterns for any given region. Thus, you are jointly classifying all the ozone and meteorology for a given synoptic scenario. The clusters are an average over approximately 1500 m, within the mixed layer (e.g. a mixed-layer trajectory approach).

Mr. Rao commented that for the period 1989-1993 the ozone data can be clustered into primarily 3 categories. The data cannot distinguish the southerly cluster from the southwesterly cluster. But again, the low ozone is again associated with the northerly flows. He noted that if you look at selenium (Se) data over this 5-year period the southerly and southwesterly trajectories tend to dominate this distribution. Zinc (Zn) is similar to selenium.

Glenn Cass asked "did you recompute your optimum length of the backtrajectory calculations for the particles like you did for the ozone?"

S.T. Rao responded no. He continued that for sulfur (S) the southerly and southwesterly winds tend to dominate. He added that arsenic (As) is dominated by the northwesterly cluster, which also identifies the relative source regions of the pollutants.

David Chock asked if Mr. Rao looked at one day impacts.

S.T. Rao responded no, but we could have done this.

Harvey Jeffries stated that you're using modeled wind data (e.g. the NGM), which is based on twice a day soundings. He asked how can you base trajectories on twice daily soundings when we know from experience that this type of information is useless in summertime ozone modeling.

S.T. Rao responded that when you cluster trajectories into traditional, synoptic patterns, then you begin to develop some type of scenario with which you can gain some confidence. He added that we're simply analyzing synoptic patterns and where the respective contributory regions are located.

With regards to summer ozone data, Mr. Rao stated that he is not saying anything about transport. He is simply talking about the area of influence. Perhaps three days is not appropriate, perhaps it should be two days. He requested that the Work Group evaluate the methodology and fine tune the system later.

Steve Ziman commented that mitigate and transport do not equate.

S.T. Rao responded that this is why you use a climatological scenario. You should use an approach that looks at the problem and gives you the potential areas over which the transport could potentially occur. If you go into the level of detail that you are trying to require here, then the process bogs down, and becomes intractable. He suggested moving on to the time series analysis. He added that he did not think that anyone could prove what the transport is. He thought the issue was unsolvable.

For example, regarding the 0.5 correlation coefficient for Greenbelt, Maryland; all this says is that the weather effects correlate within this region at 0.5 or greater. The meteorology correlation has a much larger footprint; and, subsequent years have different footprints. Thus,

what you can observe are the weather-induced effects from year to year on surface ozone concentrations.

Harvey Jeffries responded "NO!!" He said this does not say anything about whether Virginia's emissions are affecting what is going on at Greenbelt. All this says is that the two monitoring sites went up and down together BECAUSE OF THE METEOROLOGY! He concluded that it says absolutely nothing about the correlation of the emissions and ultimately the transport/AOI concept.

Fred Vukovich, SAIC, commented that in 1988 we had very little transport because it was a stagnation event. Thus, the area would be expected to get larger.

S.T. Rao noted that it is very difficult to move from these statistical concepts to transport. He suggested that it is somewhat easier from the trajectory perspective, but it is virtually impossible using the statistical decomposition procedure. However, if you can determine the space and time scales, then you can address the issues of AOI and AOV.

Harvey Jeffries commented that S.T. Rao's inference here is not plausible. He explained that just because the monitors correlate with one another tells you absolutely nothing about the emissions contributing anything to transport. He thought that it is very wrong to say anything about an area of influence where there is no implied cause and effect.

Steve Ziman cautioned that we have to be careful that we do not give credence to an idea (e.g. AOI) that is flawed and not founded in detailed, rigorous science.

S.T. Rao said that Bruce Hill stole his bottom line, but relying on grid-based photochemical is dead wrong.

Harvey Jeffries stated that we will have difficulty assigning cause and effect. He added that observations don't explain anything, they simply say that the ozone is at the monitor at a specific time. However, photochemical modeling is the only means of getting from emissions to ozone concentrations - data only has certain powers.

S.T. Rao commented that if the models are truly capable of defining atmospheric processes and rendering ozone concentrations (e.g. ROM 1988 runs for June, July and August), then why does the data show a footprint on the order of several hundred kms, while the model data only shows a footprint on the order of 50 kms? Data do not lie. Data are accurate representations of the state of the environment - an eye witness per se. He noted that he has a great deal more confidence in data analysis as opposed to the results of numerical photochemical grid models.

Harvey Jeffries stated that we are all in agreement that looking at one or two episodes using numerical models is not sufficient. However, you have to come back into these individual events and do complex grid modeling in conjunction with detailed data analyses to solve the problem. He added that this is the message that we need to return to our colleagues on the FACA Subcommittee.

Steve Ziman asked what do we say about all of this tomorrow? We are talking about AOIs and AOVs and science is a relevant issue.

Harvey Jeffries commented that this is not on the agenda. He noted that it is basically part of Chapter 5 of the Conceptual Model Document and he will address this issue tomorrow in the FACA Subcommittee.

Glenn Cass stated that it doesn't seem to him that we have the obligation to provide the answer from the STSWG. He said a good deal of S.T. Rao's work is promising, albeit there are some concerns. He suggested that the Work Group could provide constructive comments to S.T. Rao on how we might develop a better technique to arrive at our consensus for AOI/AOV.

Areas at Risk for Nonattainment, Steve Ziman

Steve Ziman stated that he had no real comments and asked for comments from the work group members.

Harvey Jeffries commented that with regards to Option 2 on page 3, in this paper - "track air quality, emissions trends ...." he took objection to the request in the second paragraph where they state that an explanation of meteorological variability could be requested from STSWG. He asked if there was any way to adequately correct data for meteorological variability?

Steve Ziman responded absolutely not.

Dave McNeill responded that this is a policy issue, not a science issue and that we should not address it.

Tom Helms suggested that we can state this position and simply send it back to the authors for revision and/or clarification.

Integrated Implementation, Mark Scruggs

Mark Scruggs announced that the most recent version of this issue paper was dated September 9, 1996. Mr. Scruggs said that he agreed to synthesize and gather the STSWG opinions and get these back to Donna Lamb. He noted that the Work Group is going to have to define the data and tools necessary to perform the integrated implementation.

Steve Ziman commented that different people will have different ideas about integrated implementation.

Mark Scruggs asked for members to provide him with comments..

Harvey Jeffries asked for an explanation of the options listed on Page 7.

Mark Scruggs responded that he was not sure. However, he thought the key elements here are tools, data availability and analyses.

Harvey Jeffries suggested that the STSWG focus on the tools that are needed in our response through the Conceptual Model Document.

New Source Review, Dave McNeill

Spatially Integrated Plan -

Dave McNeill stated that there are the same requirements within an AOI and an AOV. He commented that he did not understand why they would want to do this. He noted that Work Group consensus is Option 4 which allows caps, trades and offsets, without inter-pollutant trading initially. Eventually, it will allow inter-pollutant trading.

Mr. McNeill stated that he has problems with the trading currency similar to the problems we discussed earlier today. Mr. McNeill said he would go through this paper and the new revision and attempt to formulate a draft response for distribution to the Work Group for comment/discussion. He noted that PM-fine increments could potentially be a problem.

Glenn Cass asked does this mean that you effectively have a zero increment for all sources? What does it mean not to have a zero increment?

Steve Ziman asked what does it mean to have an increment with which one has no faith in?

Dave McNeill responded I am not sure. He noted that if you have emission limits which are so close to background, he was not sure that it would really make a difference. Essentially, it would mean that the ambient standard would control itself.

Glenn Cass asked what would it mean if the ambient standard would control new sources in the west?

Mark Scruggs commented that obviously in the west you are dealing with an area that will be very sensitive to change in terms of PM-fine. The increment levels that are being discussed are very small.

Attainment Dates, John Cabaniss

John Cabaniss said that there are currently a total of seven (7) options for attainment dates. He noted these options were first discussed in September 1996, during a STSWG conference call. To date, he has gotten some comments and has provided initial comments to Herb Williams. Mr. Cabaniss noted that the options currently range from what the Clean Air Act currently states (e.g. Section 172 jargon), all the way to taking reasonable further progress or setting a timeline for improvement. Thus, the continuum runs from the strict, well-defined Clean Air Act (CAA) approach all the way to the loose, not so well-defined current thinking.

Mr. Cabaniss stated that this is largely a policy decision inter-mixed with a couple of technical issues. Key science issues are how you define an attainment date and the concept of areas that will go into and out of attainment. Also, in terms of reasonable further progress, how do we actually quantify this in terms of an integrated implementation policy. He noted that he has not received any new comments from anyone since the Norfolk meeting. We are working on this paper, and will report progress to the group as progress is made.

Steve Ziman commented that we have discussed the feasibility of reaching attainment in certain areas. This must be discussed, and it should be incumbent upon the areas and the agencies to show what they will do should they not be able to achieve a given standard.

Tom Helms asked Mr. Ziman to give a presentation at our next face-to-face meeting on his research.

Cyril Durrenberger commented that he thought it would be impossible to reach attainment in Houston - it would require 80-90% reduction in VOC to reach attainment, according to our current modeling. This is simply not attainable. He was very concerned if they will ever be able to reach attainment in this area. He said they can undoubtedly make progress, but reaching attainment is going to be extremely difficult. In terms of Dallas, Mr. Durrenberger said they have installed a PAMS site and done a good deal of mobile source testing and monitoring.

S.T. Rao asked if the problems could be an artifact of the monitor placement plan.

Cyril Durrenberger responded that he did not think so.

Steve Ziman commented that he wanted to incorporate what Al LeFohn has done into analyzing the Houston problem.

John Cabaniss stated that for areas that would be considered more marginal nonattainment areas, it would be difficult to justify having a long 10-year planning cycle to show attainment. He advocated potentially a different approach for these less problematic

regions. The 10-year cycle may work for Houston but he considered this approach inappropriate for say, Toledo.

Bob Judge asked "is the 10-year planning cycle in addition to an emission reductions cycle?"

John Cabaniss replied no, it is mixed with the rate of progress controls.

The meeting was adjourned for the day.

Tuesday, October 29, 1996

Work Group Participants

Name	Affiliation

Tom Helms, Co-Chair	U.S. EPA

Harvey Jeffries, Co-Chair	UNC - Chapel Hill

David Chock	Ford Motor Company

John Cabaniss	AIAM

Bruce Hill	Appalachian Mountain Club

Dave McNeill	Utah DEQ

S.T. Rao	New York ARB

Jay Rosenthal	USN

Mark Scruggs	DOI

Dan Weiss	Cinergy Corporation

Jeffrey West	GPU Services Corp.

Steve Ziman	Chevron Corporation

Leon Outlaw (for Jay Hudson)	Santee-Cooper

Work Group Members Not Participating

Diana Andrews	Kentucky DEP

Glenn Cass	Cal Tech

John Core	WESTAR

Ellis Cowling	SOS

Kirit Chaudhri	Virginia DEQ

Rich Poirot	Vermont

Non-Work Group Participants

Bob Wayland, Fred Vukovich, SAIC; Bob Imhoff,TVA; Don Blumenthal, STI Corp.; Pradeep Saxena, EPRI; Bob Judge, EPA/Region I; Ken Schere, EPA/ORD; and David Sanders, U.S. EPA/OPSG, Cyril Durrenberger, Dick Karp, Dave Harper, James Red, Jim Smith, Mike Fishburn, TNRCC.

Summary of the Meeting

How Meteorology Affects Ozone, Fred M. Vukovich (SAIC)

Fred Vukovich, noted that his studies indicate the highest ozone concentrations are found on the back side of slow moving high pressure systems. For example, on July 3, 1990 the highest ozone concentrations occurred on the backside of the high pressure system. The area of high ozone was relatively confined. On July 23, 1990, following a strong frontal passage, the ozone concentrations were drastically reduced.

Fred Vukovich said that more important is a "stagnation event" which occurred between July 1-10, 1988. This occurs when a high pressure system becomes quasi-stationary. On July 8, 1988, ozone concentrations of 140 ppb were centered over the northeastern United States and a much larger area is affected by the episode. All surface layer wind speeds were less than 2 m/s on July 8, 1988 at 0700 LST.

S.T. Rao asked Mr. Vukovich if he could define transport.

Fred Vukovich stated that it is sufficient atmospheric flow to move pollutants/precursors over long distances. He added that synoptic systems are large and will affect large areas. He said that the regions where you have chaotic winds, subsidence and very little transport are most affected by these ozone events or episodes. Mr. Vukovich said that the variations are related to the atmospheric chemistry and meteorology - correlations can only show consistencies and really do not speak to transport.

Mr. Vukovich responded that transport can occur when the high pressure system moves out (e.g., the center of the reforms in a different location). Additionally, vertical mixing is important in addition to the horizontal transport.

S.T. Rao asked if Mr. Vukovich could define transport from a policy perspective.

Fred Vukovich responded that he is not a policy person.

S.T. Rao suggested that we must be able to do this. He said the STSWG has been asked to develop a sound scientific approach to support the policy development for the AOI/AOV issue. He said that if Mr. Vukovich could not address the policy perspective then the Work Group needs to identify who they can bring to the table to discuss the issue.

Fred Vukovich said that if he were to design an analysis, he would end up with two forms of the analysis. First, he would deal with the stagnation events associated with high pressure systems, which effect large regional areas. Second, he would deal with special events, where transport is dominant and extremely important. These events are difficult to identify, and they generally cannot be obtained from observations. The only way to do this is to use observations to key on episodes, and then use models to identify the pertinent processes contributing to the episodes. Also, there is potential for using trajectories to support these types of determinations.

Regarding Robin Dennis' work, Fred Vukovich noted that Mr. Dennis was doing some work on deposition and he decided to look at the range of influence using the Regional Acid Deposition Model (RADM) and meteorological outputs from MM5. Nineteen (19) of the cases looked at were in the wet group (e.g. storm situations) and 19 were in the dry group (e.g. no rain). He took 30 cases and applied this to the ozone range of influence, for Pittsburgh and Atlanta. He then changed the NOx emissions and looked at the range of influence for ozone (at the surface). The major axis of influence for Pittsburgh was approximately 800 km; this radius was elongated and centered along the ridge of the Appalachian Mountains. The major axis of influence for Atlanta was approximately 300 km; this radius was more circular. Mr. Vukovich noted that both of these estimates are most likely over-estimates.

Fred Vukovich commented that Mr. Dennis used 3-day integrations (essentially transport), which he discussed with him. He agreed that they should indeed be run longer for ozone. Mr. Vukovich suggested running a 30-day simulation during summer. He also recommended looking at the high pressure system meteorology as well. Mr. Vukovich added regardless of whether you calculate a range of influence, you have to determine whether you're really affecting anything within that range of influence. In all the cases where ozone is an issue, you are transporting ozone of concentrations greater than 70 ppb.

Tom Helms asked Mr. Vukovich to identify two-three things that he should take from his presentation.

Fred Vukovich identified the following:

(1)	You understand the meteorology of ozone.

(2)	If you want to look at the area of influence, this is a transport issue. I don't think transport can be addressed in any way other than using a model. This model could be a trajectory model or an air quality model. However, in both, you need good meteorology and good emissions.

Tom Helms asked if the back side of high pressure systems was important.

Fred Vukovich responded that they are important.

Jay Rosenthal agreed that it is generally the back third, to the back half of the high where you are likely to find the inversion.

Harvey Jeffries noted that for PM and deposition, Mr. Vukovich's work tends to suggest that they are in one climatology and that ozone is under a different climatology.

Fred Vukovich responded that he has only done one study where he looked at particles. In this study, he had high particle concentrations when he had high ozone concentrations. But, that was only one EPRI study, and those results are not conclusive.

Middle Tennessee Intensive Field Study, Bob Imhoff, TVA

Bob Imhoff highlighted the following with regards to the Middle Tennessee Field Study:

(1)	In Nashville in 1995, the ozone episode was very localized.

(2)	All NOx is not created equal.

(3)	NOx reactivity in both urban plumes and power plant plumes is over relatively quickly. Thus, the majority of transport is in the form of ozone, and not the NOx.

Mr. Imhoff noted that there are similarities and differences between the Atlanta and Nashville studies.

Approach

The objective for the Nashville study was to characterize the atmosphere in 3-dimensions (3-D) using airborne data, tethered balloons, profilers, sondes, and use a process-oriented study.

Elements of Study

The following were identified as key elements of the Nashville study:

6 aircraft to assist in taking measurements

108 level-1 sites (air chemistry) + level II and III sites

Meteorology was taken into account (5 profilers, CLASS sites and surface observations)

Emissions inventory (biogenic and anthropogenic) developed

Extensive QA/QC performed.

The results from the regional analysis were very organized, for the period June 19 - July 28, 1995. He said that July 12, 1995 was very unique and suggested that the Work Group explore this in greater detail. The LIDAR results over the center of Nashville show concentrations of ozone at 120 ppb. The TVA Helicopter Results showed that NOy sources are very localized. The ozone data appeared to show some transport of ozone downwind through the city. The ratio of ozone to NOy was also interesting; ratios as high a 7 are recorded. This day was under a stagnant high pressure system as well, similar to what Mr. Vukovich discussed earlier.

The ozone production efficiency ("low" SO2, e.g. SO2 < 2 ppbv) during this study was as follows: for each NOx unit that has gone through the cycle, approximately 8 ozone units were produced. For "high" SO2 (e.g. SO2 > 2 ppbv), the production rate is approximately 5 ozone units. Please note that the SO2 is simply used as an indicator of the presence/absence of a power plant plume; it does not imply the importance of SO2 on ozone chemistry).

Harvey Jeffries commented that in layer one of UAM, deposition is a huge removal process for NOx.

It was noted that from analyzing the NOz / NOy ratio, that 30 kms from the plant,the majority of the ozone production is done (e.g. chemical age is > 0.7) for a small plant (e.g. 60 tons/day of NOx). For larger plants (350 tons/day of NOx), it could take approximately 100 kms.

Bob Imhoff stated that the UAM-V model results showed a similar slope of correlations between ozone and NOz for both the observations and model concentrations. Also, it was shown that 48-hours was the temporal limit for effecting ozone concentrations > 100 ppb; e.g. if you turn off all the NOx emissions (including biogenics; however, biogenic VOCs were retained) in the OTAG domain after 48-hours, the effects stabilize at approximately a 70% reduction in the number of cells experiencing ozone concentrations > 100 ppb.

Bob Imhoff offered the following summary of the Nashville study:

The study included a comprehensive measurement program

The meteorological variability was excellent

A major ozone episode occurred July 11-15, 1995 which was a very localized episode. The ozone delta was approximately 80 ppb.

All NOx is not created equal

NOx reactivity is short-lived in power plant plumes; it is also not simply power plant plumes vs. Urban plumes, but we are seeing variations among different power plant plumes.

Harvey Jeffries asked Bob Imhoff what he could infer about AOIs from this work?

Bob Imhoff replied that the one thing he could infer is how quickly the curve flattens out after turning off the NOx. The curve was markedly reduced within 48 hours.

S.T. Rao asked if all of these results are based on UAM-V episodes.

Bob Imhoff responded that they were all based on UAM-V.

S.T. Rao asked if the chemistry was valid when we do these simulations where we turn off all the NOx.

Harvey Jeffries responded "absolutely." He noted turning-off the NOx does not affect the

model chemistry and the results at all. There is still NOx in the system, it is simply decaying from the system very rapidly.

NARSTO-Northeast Measurements, Don Blumenthal (STI)

Don Blumenthal said that this study measured ozone, NOy, VOCs, carbonyls, SO2 and CO (aircraft data) for July 31 and August 1, 1995. He suggested that July 31, was a build-up day. On this day, a high pressure system was present with very little transport. On August 1, 1995, the high pressure system had moved off to the east, and a noticeable westerly flow had developed. There was definitely transport within the region on Day 2.

Jay Rosenthal commented there was also an upper level closed anticyclone, which is also indicative of substantial stagnation and subsidence.

Don Blumenthal stated that on July 31, 1995 the maximum ozone concentration exceeded the NAAQS predominantly in the major urban areas (e.g. Philadelphia, Baltimore, New York, Pittsburgh, etc.). On August 1, there was a more organized flow and much wider area of exceedance which is much more typical of the back side of the high pressure system. The exceedances were organized along the northeast corridor.

Don Blumenthal noted that ozone transport in the region is predominantly from the west to the east. There are ozone concentrations exceeding 80-90 ppb aloft that would be mixed down to the surface as the sun rises and the PBL turns over. Thus, if we are discussing a standard that could be an 8-hour standard or 0.08 ppm, then these rural areas would definitely be in exceedance of the standard.

Harvey Jeffries commented that it is not simply the ozone aloft that causes the problem. You must have new NOx to "kick" the system and provide the charge for generation of new ozone during day 2.

Mr. Blumenthal noted the following conclusions regarding the NARSTO Northeast study:

Ozone and precursors can be high at the boundaries and transported into the region.

The affect on exceedances is uncertain, but is being investigated

Ozone concentrations of 80-100 ppb can remain aloft all night, and provide a "charge" for the next day

Aloft concentrations and meteorology are not represented by the surface conditions/measurements

Mixing heights increase more slowly on wide-spread episode days

The existing upper air network is inadequate

Complex coastal meteorology is not well understood.

Meteorological Air Pollution Complexities, Jay Rosenthal (USN)

Jay Rosenthal said that the visibility analyses which were used traditionally were National Weather Service (NWS) measurements. He noted that visibility changes have a diurnal pattern. Low visibility begins along the Southern California coast during early morning hours. Low visibility then moves inland during the day, prior to being blown west during the mid- evening hours to complete the cycle. Mr. Rosenthal noted that Southern California experiences these types of visibility oscillations quite frequently. He added that this is a reversal between the land and sea breezes. These events are characterized in Southern California by light winds, mountain blockages, and the subsequent wind reversals.

Smog Transport Mechanisms and Issues

Jay Rosenthal identified an inversion region located over the LA Basin/San Fernando Valley. The coastal regions are classified by strong southeasterly flow around the so-called "Catalina Eddy". Frontal incursions at the northern end of the basin are responsible for "cleansing" the region. There can often be more than one low-level inversion in coastal California. He identified sea breezes and mountain valley breezes as terrain and coastal induced complexities. Twenty-four (24) hour surface trajectories were calculated, which terminated at Simi at 0600 LST. Simi is one the highest exceedance locations in Southern California. Readings indicated that during the morning hours, southeasterly flow greatly impacts this region. Later in the day, early evening these trajectories become more westerly and northwesterly.

Southern California Ozone Study (SCOS - 97)

Mr. Rosenthal noted there was a good density of observation points and upper air meteorological sites. He said the bottom-line is "if you're really going to look at transport issues, you need a dense network of upper air stations."

Mr. Rosenthal identified the following as goals and objectives of SCOS-97:

Assess the magnitude of the situation both at the surface and aloft

Observe ozone episode conditions in 3-D; you cannot assess transport accurately without using a three dimensional analysis.

Mr. Rosenthal described the following as three noteworthy findings from SCOS-97:

(1)	An absolute requirement for looking at data in 3-D

(2)	The need to be aware of coastal effects from things like eddies and fronts

(3)	When looking at the large scale synoptic variability, you can forecast highs, lows, ridges and troughs, but lets look at the correlation of these synoptic events with ozone conditions.

NARSTO-Continental, Ken Schere (via telephone)

Ken Schere, EPA, made the following slide presentation about the NARSTO-Continental study:

Slide #1:

NARSTO-1988 State-of-Science Assessment

- a 10-year research strategy for tropospheric ozone research

Slide #2:

Overarching Policy Questions

(1)	What changes have occurred in tropospheric ozone science over lat decade that might alter of confirm the course of air quality management strategies?

(2)	How manageable is the ozone problem for a given area?

(3)	Are existing emission control measures helping to bring the ozone problem under control?

(4)	What are the relationships between the ongoing efforts to manage the tropospheric ozone pollution and the scientific understanding of the issues?

(5)	What are alternate approaches?

(6)	How can we best track and assess our progress?

(8)	Will our efforts to manage ozone help or hinder other environmental projects (e.g. Acid rain, etc.)?

Slide #3:

What are the most significant research developments in tropospheric ozone science over the last 10 years?

How does ozone accumulation on urban (< 200 km) and regional (200 - 2000 km) scales depend on the source dimension and location?

What re most recent assessments of the relative contributions of VOC, NOX and co to ozone accumulation on urban and regional scales?

What are the strengths and limitations of the current scientific methods and tools?

Slide #4:

How are we going to get there?

We have designed numerous "Critical Review and White Papers", which will be authored by noted scientists in these disciplines.

Critical Review Papers:

Air Quality Trends - S.T. Rao and George Wolff

Methods Development - Fred Fehsenfield, W. Neff and P. McMurry

Monitoring Networks - Ken Demerjian

Process Insights From Field Studies - N/A

Dry Deposition and Removal Processes - Mark Wesely and Bruce Hicks

Atmospheric Chemistry - R. Atkinson (Gas Phase)

Chemical Kinetic Mechanisms - Marsha Dodge

Aqueous Chemistry and Wet Removal Processes - N/A

Meteorological Processes - Nelson Seaman

Air Quality Model Development - Robin Dennis and Ted Russell

Air Quality Applications (model oriented) - Phil Roth, Tom Tesche and John Seinfeld

Mobile Source Emissions - William Pearson

Stationary Source Emissions - M. Placet

Natural Source Emissions - A. Guenther

White Papers:

Field Study Intercomparisons - G. Hidy, P. Solomon, Ellis Cowling

Risk Management for Air Quality - G. Hester

Slide # 5:

Composition of Synthesis Team

Science - Government	Dan Albritton

Science - University	Bill Chameides

Ken Demerjian

Science - Private	Phil Roth

Stakeholder - State/Local	Praveen Amar

Stakeholder - Industry	Howard Feldman

Alan Hansen

George Wolff

Policy - US	John Bachmann

Policy - Canada	Carmelita Olivotto

Policy - Mexico	Francisco Guzman

Slide # 6

Schedule

December 31, 1996	Detailed outline of review papers

June 30, 1997	First draft of paper available for review

August 15, 1997	Comments received from NARSTO Reviewers

September 1, 1997	Last Date for receipt of first drafts

November 1997	Science Symposium

December 31, 1997	Revised drafts incorporating NARSTO comments, submitted to Atmospheric environment for publication

Slide # 7

Assessment Report

1/97	Synthesis Team meeting

7/97	Draft critical review papers become available to the synthesis team

Summer 1997	Synthesis team writing retreat

Fall 1997	Synthesis tea writing retreat

March 1998	First draft of the assessment report

April 15, 1998	NARSTO reviews received

May 30, 1998	Second draft of assessment report due

July 15, 1998	Comments received on second draft from NARSTO reviewers

9/98	Third draft of report due

11/1/98	Comments form NAS

12/31/98	Publication of Assessment Report

There were no questions regarding Mr. Schere's presentation.

Harvey Jeffries said that there are some papers that we will focus on next time in Denver. As a result, his presentation today to the FACA subcommittee will be very general in nature. He asked Work Group members to get any comments on the AOI/AOV issue to S.T. and Tom Moore as quickly as possible.

Status of the Conceptual Model, Harvey Jeffries

Harvey Jeffries said that we have been diverted from this document towards issue papers recently. Chapters 1-4 have already been distributed to Work Group members. I have received additional information from Glenn Cass, S.T. Rao, and Fred Vukovich for Chapter 5. He suggested the Work Group draw a line and finish Chapters 1-4, and go ahead and release this information to the FACA subcommittee members. Mr. Jeffries will work with Tom Helms and the contractor to get a revised version of Chapters 1-4, prior to the next FACA meeting for review. Review and comments on the Conceptual Model will be closed off after the next FACA meeting.

Harvey Jeffries stated the need to develop a chapter related to tools. Rich Scheffe has made a crack at this, but it needs to be revised substantially. He commented that the work group needs to understand the status of models, and the integration of PM into ozone models, and include this information into this chapter of the Conceptual Model.

Finally, Mr. Jeffries noted that it has been suggested that STSWG generate a couple of papers on it's own (e.g. variability in time and space; going into and out of nonattainment; tools issue, etc.). These issues have been discussed previously, but have sort of died in recent months. Thus, we must re-focus on climatology and formalize some of these issues. David Chock agreed to take a first crack at this and distribute it to the Work Group for comments.

Regarding tools, Harvey Jeffries asked what do we want to do about data to make the tools work? Perhaps, he said, this chapter should be called "Tools and Data" - however, this is all future work. If this document containing chapters 1-4 is not released before mid-December, it is probably not much use in delivering it at all.

S.T. Rao asked what is going to happen between now and the next FACA meeting.

Tom Helms replied he honestly did not know. Mr. Helms will sit down with Harvey next week and caucus on this. He said it seems that we should be finalizing the issue papers (based on what is discussed this afternoon), finalizing the Conceptual Model, and moving forward.

Harvey Jeffries asked if there would be a call next Tuesday on Election Day?

Tom Helms responded that there would be a call next Tuesday and whoever can play will be there. He noted the others will have to gather the information as best as possible.

Harvey Jeffries stated the AOI/AOV and integrated implementation are definitely going to hang around and will be issues at the Denver meeting.

The meeting was adjourned.