Air Resources Impact Work Group

This is the final report of the Air Resources Impact Work Group.

• Meeting schedule/agenda/minutes
• Work group members
• Meeting information

Meeting Schedule/Agenda/Minutes

July 18, 2002 DEQ Central Office

August 8, 2002 DEQ Central Office

September 9, 2002 DEQ Central Office, 10 a.m.

October 9, 2002 DEQ Central Office, 10 a.m.

NOTE: All scheduled meetings will be held at DEQ's Central Office at 629 East Main Street. The meetings will be in the first floor conference room and are scheduled to start at 10 a.m.

Work group members

Meeting information

Cumulative Impact Study (power point format)

Submissions by work group members

• Submission #1
• Submission #2
• Submission #3
• Submission #4
• Submission $5              

Submission #1

In the Tenaska Remand Case, Tenaska had a good definition for combined or  "cumulative impact."  It's in the SCC hearing examiner's Report on Remand.  It may have come from the EPA or directly from the Clean Air Act:  Modeling of all  of the existing emissions within an area specified by DEQ, to determine whether the combined emissions exceeded what is called an allowable increment under the PSD Program, which is some fraction of the NAAQS.

The "permit by permit" modeling process is adequate only if all existing and proposed facilities/uses are factored into the analysis.  

The cumulative impact studies being filed in Commission Cases (i.e Tenaska) consider the cumulative impact of ozone.  The real question is which standard should be applied, the 1-hour standard or the 8-hour standard.  The other issue is moving from the PM10 to the PM 2.5 standard.  There has been a lot of conflicting testimony:  the monitoring stations do not measure PM2.5; some of the monitoring stations measure PM2.5, but we haven't collected enough data to analyze the results; there is no air quality model for PM2.5, etc.  This is an issue that will have to be resolved soon.     

The geographic scope should be expanded.  We should consider the overall impact of all these power plants on air quality in Virginia.  The companies proposing these plants are not dumb; they site them in rural counties that are currently in attainment of the national ambient air quality standards.  What will be the effect of all this additional pollution on areas that are already in non-attainment?  We should not look at minor sources, unless you want to start looking at everyone's car.  It has been said that one combined cycle power plant creates the same amount of pollution as 5,000 cars.  If you want to control air pollution you have to control urban sprawl.

Proposed sources should be considered.  In cases before the SCC the cumulative air impacted study included every power plant that had filed an application for an air quality permit from DEQ.

With number of studies being done, the cost of the studies should go down.  The hard part was collecting all the data from the DEQ monitoring sites, which is maintained by the regional offices.  If the data was maintained in a central database this would facilitate the process. 

More monitoring stations should be added, and each monitoring station should measure all criteria pollutants as well as ozone.  Right now, the monitoring stations we have do not measure all criteria pollutants, and there are some serious gaps in the coverage of the network.  

With respect to combined impacts:  Do such elements effect only new facilities or apply also to enhancements to existing facilities?

Are previously rejected projects open to reconsideration upon improvements to existing facilities (ie: add scrubbers in a given area)? 

With respect to geographic scope:  Does this include region beyond VA?

With respect to the inclusion of proposed sources:  If so, at what stage of project development should a proposed project be included? What criteria determines inclusion?     

Are previously considered projects subject to reconsideration because of additional proposals or withdrawal of prior proposals?

Are previously rejected projects open to reconsideration upon withdrawal of previously approved projects?

Should there be a waiting que for rejected proposals for reconsideration upon changes in circumstances? 

What role will Regional Transmission Organizations play in this process for generation or transmission additions/improvements?

Does one consider economic tradeoffs between generation and transmission?

How will database be maintained & updated (thoroughness, frequency, etc.)?

What is affect on timeliness of processing applications, particularly when several projects are porposed simultaneously?                

Submission #2

Ozone-related Questions or Issues

Is there a legitimate need to re-evaluate the combined impact (of existing and proposed sources) on ground level concentrations of ozone when the future emissions of ozone precursors, particularly oxides of nitrogen, are controlled under a stringent regional cap and trade program?

Has such an analysis been completed adequately under the auspices of the Ozone Transport Assessment Group (OTAG)?

Based on past work, what is the combined impact, taking into account required NOx SIP emissions reductions, on ground level ozone concentrations in Virginia? 

Is it technically feasible to update OTAG modeling, including specific evaluation of proposed new sources?

If so, would such regional ozone modeling be likely to produce a useful result for planning or other purposes?  If yes, what would that cost?

Air Quality Factors

The rebuttable presumption is that factors commonly considered in new source review are adequate:

• All criteria pollutants
• Representative meteorology (as an input for air quality models)
• Representative ambient air quality (for consideration of attainment status)
• Air Quality Related Values (AQRVs) in Class I areas (visibility, acid deposition, etc.)
• Inventory of Existing and Proposed Sources (as modeling input)

Uncertainty regarding attainment status with respect to the new PM_2.5 and 8-hour ozone standards is an issue.

Uncertainty regarding attainment status with respect to current standards has been a stated public concern in rural areas far from existing monitors in more urbanized areas.

Availability of inventory information for existing and proposed sources is an issue.  Data bases are inadequate, particularly when assessing impacts on geographically extensive Class I areas with a correspondingly extensive modeling domain, including other states.

Lack of consideration of AQRVs outside the PSD process may be an issue (minor permits issued by the Commonwealth outside federal permitting guidelines).

If multiple proposed sources are considered, what data about each source are required and is this information available?

Methods

The panel should be briefed regarding the capabilities and limitations of the following commonly used or required models or methods:

• ISCST
• CALPUFF
• FLAG Report (Class I Areas)
• Regional models (ozone)
• Ambient Air Quality Monitoring Systems
• Continuous Emissions Monitoring Systems (CEMS)

Issues include:

                There is no approved method for ozone impact modeling for individual sources, let alone multiple discrete sources. 

                Availability and implementability of methods to address Class I combined impacts.  (The panel could benefit from a briefing from the Park Service and/or Forest Service technical experts concerning the state of the art-at least, I believe I could benefit from such a briefing.)

Uses of Combined Impact Analysis Information

What do the results of recently completed combined impact analyses show?  Do those exercises show that the effort of preparing such analyses is of sufficient value to decision-makers?

Should similar or other such information be provided to the State Corporation Commission as background for their deliberations concerning Certificates of Need for new power facilities?

If so, is it appropriate to consider existing sources plus the proposed source, as in the PSD program, or to consider as well the potential effects of projects that have not yet been issued permits and which are, in that sense, speculative.

Is the threshold for combined impact analysis included within the PSD regulations appropriate?  If not that (significance) threshold, then what threshold would be appropriate for contexts outside of the PSD system?

Costs

It may be agreed that ozone is the most important pollutant to focus on, particularly related to new generation sources that produce oxides of nitrogen (precursors to ozone formation in the atmosphere).   The DEQ has good, but limited, technical resources to help address these most difficult modeling issues.

What guidance can the panel provide to DEQ such that modeling resources are best utilized? 

What are the costs associated with maintenance of  complete emission inventory data bases for all existing sources in a form readily available for impact analysis purposes?

What guidance should DEQ or the SCC provide to permit applicants concerning required analyses?

What activities do the Federal Land Managers undertake to address these issues?  If there is a gap between activities of the FLM, applicants, the DEQ, and EPA, what is it and how might it be addressed?               

Submission #3

What Are Combined Impacts?

Combined impacts represent air quality impacts resulting from a proposed facility's emissions in addition to impacts from existing sources of air pollution and in consideration of other currently proposed facilities within a defined geographical region. 

How And To What Degree Are Combined Impacts Currently Assessed?

Combined impacts on ambient air quality are assessed primarily through the use of air quality dispersion models.  Data collected by ambient air monitors located throughout the state is used as part of the assessment.  To assess combined impacts, a multi-source dispersion modeling analysis is conducted incorporating proposed facility emissions and emissions from an approved emissions inventory to account for existing (and proposed) stationary sources in the defined geographical region.  The boundary of the geographical region or modeling domain is typically a distance of 50-75 kilometers away from the proposed source and varies depending on factors including topography, meteorology, and stack parameters including stack height, exhaust temperature, and flow velocity which influence the dispersion of stack plumes.  The emissions inventory is a compilation of emissions data from existing (and proposed) sources and is a very detailed, labor-intensive task that often encompasses emission sources from other states.   

Once the emissions inventory is compiled and approved, multi-source dispersion modeling is conducted using a U.S. EPA approved model.  Results from the modeling analysis are used to directly assess compliance with applicable Prevention of Significant Deterioration (PSD) increments.  To assess compliance with applicable National Ambient Air Quality Standards (NAAQS), the modeling results are added to background ambient pollutant concentrations based on data collected by ambient monitors.  The NAAQS assessment is conservative in that existing stationary source emissions are "double-counted" since they are reflected in the ambient background concentrations and are also directly included as sources of emissions in the dispersion modeling analysis.  

It is important to recognize that the above assessment is applicable to a Class II area analysis.  If a Class I area analysis is required, a more complex modeling assessment is required to predict impacts at federally protected Class I areas (national parks, wilderness areas, and other designated lands).  A Class I area combined impact analysis is an enormous effort in that the modeling domain is very large (typically 200 kilometers around the boundary of the Class I area) requiring the consideration of potentially hundreds to thousands of emission sources.  This type of effort is only undertaken in rare circumstances and requires considerable emission inventory assistance from state agencies.

The level of effort associated with a combined impact analysis is very significant though it will vary depending on certain factors including the number of emission sources within the modeling domain, the availability of emissions inventory data, and the number of pollutants of concern.  The compilation of an approved emissions inventory is a very resource/labor intensive task because emissions and emissions characteristics (stack parameters) must be precisely quantified for input into a multi-source model.  This process alone can take a team of people several months to complete if current emissions inventory data is not readily available for a given modeling domain. 

What Combined Impact Factors Could Be Evaluated During Air Permit Reviews?

Combined air quality impacts could be considered for:

·        SO2, NOx, and PM10 increment consumption (Class II - using ISC3 model)

·        SO2, NOx, CO, and PM10 impacts relative to NAAQS (using ISC3 model and in certain instances background ambient air monitoring data)

·        SO2, NOx, and PM10 increment consumption (Class I - using Calpuff model)

·        Regional haze/visibility (Class I - using Calpuff model)

·        Sulfur deposition (Class I - using Calpuff model)

·        Nitrogen deposition (Class I and sensitive surface waters - using Calpuff model)

·        Ozone nonattainment (Urban Airshed model)

Submission #4

The 4 goals that DEQ has set for the TAC are roughly as follows:

1) Develop a description (for air and water) of factors and issues that need to be addressed for permits - Many for the air where mentioned in the State Advisory Board on A.P. Report on Cumulative Effects from last year's State Advisory Board on Air Pollution (Environmental/Health Subgroup report) actually covers a lot for goals 1-3...

2) Tools available for determining or estimating impacts

3) Identify the best options to use when making a determination

4) Costs associated with the identified methods and the funding optionsavailable.

-My organization has already brought up the idea of a public/private partnership for additional monitors.  It is clearly evident that a large monitoring gap does exist in the south central portion of the state, extending into the VA central Piedmont.   It is important to mention that VA ranks last in the nation -- dead last -- in per capita spending on natural resources and parks.  Costs of new methods should be weighed against our budget for the environment.  A significant cost may not seem so significant when viewing our already poor excuse of funding for protection of the environment/citizen health.

Below are some of  my organization's concerns/issues (6 main points).

1) Air and water are not the only things needing consideration by the TAC. We should encourage better communication among federal, state, and local agencies/organizations about proposed projects.  Examples would be DHR (impacts to historic resources), VDOT (traffic impacts), FAA (impacts to radar and light aircraft), county governments (nonattainment issues under the 8-hour standard and community impacts), environmental community (seeking additional relevant information), etc.

2) That the TAC considers the new national standards on the way.  This means PM 2.5 (2005) and the 8-hour standard for ozone (2004).  These should be addressed to determine whether a new facility may jeopardize the perspective county's ability to meet the new standard.  While it is DEQ's statutory authority to abide by the standard now in place, it has a morale obligation to the health of the Commonwealth's citizens, the County's fiscal impact if it were designated nonattainment, and the environment (which is known to be affected at levels far below the human health based standards) to determine if these new facilities will cause a violation once the new standards are in place...

3) Another point we should focus on is incorporating information from other organizations.  Just as industry is looked at as an information resource, so should environmental and health organizations.

4)  We should review whether or not the Federal standards are stringent enough to protect the citizen health/environment.  Are there areas in which VA should consider an overlay standard or something for the entire Commonwealth.  For example, the recent strengthening of California mobile source emission limits (especially after the Federal Courts struck down an extension of the clean air deadline for the Washington DC area).

5) Whether an energy conservation plan could reduce future demand in such a way to reduce Virginias contribution to its own pollution woes.  A good start would be with state government offices and primary and secondary educational institutions...Let the State lead by example.

6) Are we lacking anything that would prohibit us from developing an accurate picture of the problem/solution?  Ex- monitors, monitors, monitors, modeling tools...?               

Submission #5

The primary issues that we see, based on our current understanding of cumulative impact modeling in Virginia, are listed below: 

(1) Data considered in modeling.  The information included makes a significant difference in the usefulness of cumulative impacts modeling.  Two of the most important issues to decide are (1)  the breadth of the geographic area to be included; and (2)  the range of the facilities to be included (size of facilities, whether proposed or actual, at what stage in the permitting process, etc.) .  If the modeling is to be informative, both the geographic range and the range of facilities included have to be broad enough to provide useful information on whether the combined impacts of increased emissions will be adverse.

(2) Data needed for modeling.  How to efficiently gather useful and reliable data to be used to model cumulative impacts.

(3) Pollutants to be examined in cumulative impacts analysis.  It was noted at the first meeting that ozone is not among the pollutants examined in cumulative impact analyses currently conducted as part of the permitting process.  The cumulative impact of proposed and existing sources on ozone formation in Virginia, and how best to model these impacts, are issues of critical importance.

(4) Class I Areas.  The cumulative impact analysis performed as part of the air permitting process must be sufficient to measure potential impacts on all Air Quality Related Values in Class I areas.

(5) Advances in modeling protocols.  Are there modeling protocols in use elsewhere that provide better information than the protocols that have been used in Virginia?  How can the state best keep up with developments in modeling?