## Correction of WRAP region Plan02d CM AQ visibility modeling results on TSS

for Regional Haze Planning

April 27, 2011 Contact: Tom Moore, WRAP Air Quality Program Manger, 970.491.8837 or mooret@cira.colostate.edu

2018 Visibility Projections from the Plan02d and PRP18b re gional modeling scenarios for the USFS Gila Wilderness Class I area (GICL1) in the NM Regional Haze Plan were not demonstrating reasonable progress on the Worst Visibility Days, as the visibility is worsening from 2002 to 2018, see Figure 1.

Figure 1. Original GICL1 Visibility monitoring data, Glide Paths, and Visibility Projections for NM Regional Haze Plan

After discussion with the State of NM and EPA Region 6, and in reviewing the 5 principle WRAP region visibility regional modeling scenarios for GICL1 shown in Figure 2, ve ry different CMAQ results for Plan02d relative to Plan02c, Base18b, PRP18a, and PRP18b are shown fo r modeled Particulate Organic Mass on the 20% Worst Visibility Days for GICL1. This result would lead to questions about results at other WRAP region Class I areas. The difference in POM results for Plan02d to PRP18b is unexpected, because th e dominant source category of Primary Organic Aerosol emissions are the Wildfire (natural) a nd Prescribed/Agricultural Fire (anthropogeni c) types, relative to other sources of Primary Organic Aerosol emissions, see Figure 3.

Figure 2. CMAQ-modeled Organic Mass from WRAP RMC Regional Haze Planning ScenariosFigure 3. Comparison of Primary Organic Aerosol emissions source categories by WRAP region state for the Plan02d
and PRP18b scenarios

POA emissions for the Plan02d and PRP18b scenarios used by NM and other WRAP region states for their regional haze plans were to be held constant for Wildfires and dec line for Prescribed and Agricultu ral Fire. The decline in anthropogenic fire emissions results from Emissions Reducti ons Techniques applied by burners as required by the NM and other states’ Smoke Management Programs, as shown in Figure 4.

Figure 4. Comparison of Natural and Anthropogenic Fire Sources of Primary Organic Aerosol emissions by WRAP region state for the Plan02d and PRP18b scenarios

With emissions sources’ inputs to Plan02d verified to be as specified, WRAP Regional Modeling Center staff then reviewed the scripts used to extract gridded CMAQ air qualit y modeling results to be displayed on TSS at IMPROVE site locations. We have identified that a different spheroid type of geographic projection was applied when the Plan02d regional planning scenario’s air quality modeling results were extracted in Fall 2007 , relative to the projection used to extract the air quality results for the other 4 regional pl anning scenarios (Plan02c, Base18b, PRP18a, and PRP18b), which all used the same extraction scripts and spheroid type. The Plan02d CMAQ extraction results for all species would be affected (Sulfate, Nitrate, POM, Elemental Carbon, Soil, Co arse Mass, and Sea Salt), not just POM. We examined POM because it is dominated by a large and relatively unchanging source type from the planning period to the projection year.

23 Sulfate, Nitrate, and other species have a more-mixed vari ety of source types and have reduced emissions by 2018 from state and federal rules and permits.

We determined that Plan02d CMAQ extraction results were o ff by one grid cell (either x or y) for 9 IMPROVE site locations in the WRAP region, affecting a total of 15 diffe rent Class I areas in 8 states represented by those IMPROVE sites. The Plan02d CMAQ results for the Worst and Best Vi sibility Days used for Regional Haze Planning, currently displayed on the TSS are from the wrong (next-door) grid cells for 9 sites in the Plan02d scenario, and thus cause the 2018 visibility projections to either the PRP18a or PRP18b scenarios used by the 8 stat es for haze planning to also be incorrect for these 9 IMPROVE site locations in the WRAP region.

We first compared the scripts, and th en the CMAQ-extracted results between Plan02d and Plan02c cases, to isolate the locations of the extracted grid cells’ results where they are o ff by one grid cell. We then re-ran the extraction for Plan02d
with the same version of executable as Plan02c and verified the locations of the grid cells between Plan02d and Plan02c
to now be the same. We have determined that all other Class I area sites used for regional haze planning in the WRAP region, other than these 9 sites, are not affected. Four (4 ) sites outside the WRAP region and 1 WRAP region non-Class I area site (COGO1) were similarly affected – visibility projections are not made for those sites on the TSS.

The following sites, Class I areas, and state regi onal haze plans are affected by this error.

IMPROVE Site Code Class I area(s) represented State

BADL1 Badlands National Park South Dakota

CRLA1 Crater Lake National Park
Diamond Peak Wilderness
Gearhart Mountain Wilderness
Mountain Lakes Wilderness Oregon

DOME1 Domelands Wilderness California

GICL1 Gila Wilderness New Mexico

HECA1 Hells Canyon Wilderness Idaho

JARB1 Jarbidge Wilderness Nevada

MONT1 Bob Marshall Wilderness Scapegoat Wilderness
Mission Mountains Wilderness Montana

NOCA1 North Cascades National Park
Glacier Peak Wilderness Washington

PASA1 Pasayten Wilderness Washington

The correctly extracted data has been added to TSS tool s as another scenario, called “Plan02d_rev” and paired with appropriate 2018 projection scenarios. TSS users are able to compare “Plan02d” to “Plan02d_rev”, as well as to compare Visibility Projections from various combinations of planni ng scenarios (Plan02d, Plan02d_rev) to projection year results (PRP18a, PRP18b, and PRP18cmv).

Results comparing Worst Visibility Days’ for PRP18b Projected Visibility from Plan02d versus Plan02d_rev are presented for the affected sites and Class I areas in Appendix A of this memo.

WRAP staff have met by phone with affected States, EPA regional offices, and Federal La nd Managers to review these changes and address concerns and questions . This memo was circulated for review and comment. The final version of the memo will be posted on the WRAP TSS website and the a ffected TSS tools footnoted. Figure 5 show the TSS tools modified to add “Plan02d_rev” results.Figures 5a, b, and c. Modified TSS tools adding “Plan02d_rev” results at: http://vista.cira.colostate.edu /tss/Results/HazePlanning.aspx

5a. Class I area Summary Table selection for data and results on Worst and Best Visibility Days

5b. Visibility Modeling Results selection under “Modeling button” comparing ai r quality modeling results in mass concentration units (μg/m 3 ) from WRAP regional modeling scenarios.

45c. 2018 Visibility Projections selection under “Modeling button” – WRAP regi onal visibility modeling results in Deciview and Species Light Extinction scaled by Relativ e Response Factors and projected to 2018, following EPA guidance.

5

### Appendix A

Comparison of Changes to Worst Days’ PRP18b Proj ected Visibility from Plan02d versus Plan02d_rev

Plan02d

Plan02_rev

6Plan02d

Plan02_rev

7Plan02d

Plan02_rev

8Plan02d

Plan02_rev

9Plan02d

Plan02_rev

10Plan02d

Plan02_rev

11Plan02d

Plan02_rev

12Plan02d

Plan02_rev

13Plan02d

Plan02_rev

14