USDA Construction Permit - Modeling Report - (5-19-21).pdf

AIR QUALITY MODELING REPORT

U.S. DEPARTMENT OF AGRICULTURE

NATIONAL CENTERS FOR ANIMAL HEALTH

MAY 2021

TABLE OF CONTENTS

Section Page Number i USDA Construction Permit - Modeling Report - (5-19-21).docx 05/19/2021

1. INTRODUCTION.......................................................................................................... 1-1

2. EMISSIONS INVENTORY SUMMARY.................................................................... 2-1

2.1 PROJECT-WIDE EMISSIONS SUMMARY ............................................................... 2-1

2.2 FACILITY-WIDE EMISSIONS INVENTORY ........................................................... 2-1

3. AIR QUALITY MODELING ANALYSIS APPROACH AND TECHNICAL

INFORMATION ............................................................................................................ 3-1

3.1 AIR DISPERSION MODEL SELECTION .................................................................. 3-1

3.2 RECEPTOR NETWORK .............................................................................................. 3-2

3.3 METEOROLOGICAL DATA ...................................................................................... 3-4

3.4 SOURCE CHARACTERIZATION .............................................................................. 3-4

3.5 GOOD ENGINEERING PRACTICE STACK HEIGHT ANALYSIS ........................ 3-6

3.6 BACKGROUND AMBIENT AIR DATA .................................................................... 3-6

3.7 NITROGEN OXIDE TO NO2 CONVERSION ............................................................ 3-6

4. AIR QUALITY MODELING RESULTS .................................................................... 4-1

4.1 SIL AND NAAQS ANALYSIS .................................................................................... 4-1

LIST OF FIGURES

ii USDA Construction Permit - Modeling Report - (5-19-21).docx 05/19/2021

Figure 1 Receptor Network .......................................................................................................... 3-3

Figure 2 Facility Layout............................................................................................................... 3-8

USDA National Centers for Animal Health

Air Quality Modeling Report

1-1 USDA Construction Permit - Modeling Report - (5-19-21).docx 5/19/2021

1. INTRODUCTION

The U.S. Department of Agriculture (USDA) National Centers for Animal Health (NCAH) operates the National Animal Disease Center (NADC, Facility No. 85-01-017) and National

Veterinary Services Laboratory (NVSL, Facility No. 85-01-056). Together, NADC and NVSL

(the Facility) operate under Title V Operating Permit (TVOP) No. 02-TV-001R3. NCAH is proposing to replace one of NADC’s two pathological waste incinerators (Emissions Unit No. S-

4, referred to as Incinerator 4) with a new pathological waste incinerator (proposed Emissions Unit

No. S-21, referred to as Incinerator 8).

Although air quality modeling is not required for this project, NCAH elected to conduct a Class II

Significant Impact Level (SIL) analysis to determine the impacts of the replacement incinerator’s higher maximum throughput and change in location from where the existing incinerator is positioned. The air quality modeling analysis was conducted for incinerator emissions of particulate matter (PM) with diameters of 10 microns or less (PM10) and diameters of 2.5 microns or less (PM2.5), oxides of nitrogen (NOX), sulfur dioxide (SO2), and carbon monoxide (CO). The

SIL analysis demonstrated that the proposed project impacts exceed the SILs for the following pollutants and averaging periods:

• Nitrogen dioxide (NO2) – 1-hour averaging period

• PM2.5 – 24-hour averaging period

• SO2 – 1-hour, 3-hour, 24-hour, and annual averaging periods

NCAH also conducted a Facility-wide air quality modeling analysis for the pollutants that exceeded the SILs, the results of which demonstrate that the project does not cause or contribute to any predicted exceedances of the National Ambient Air Quality Standards (NAAQS).

Information concerning the air quality modeling emissions inventories, technical air quality modeling approach, and air quality modeling results are provided as follows:

• Section 2 – Emissions Inventory Summary

1-2

• Section 3 – Air Quality Modeling Analysis Approach and Technical Information

• Section 4 – Air Quality Modeling Results

2-1

2. EMISSIONS INVENTORY SUMMARY

This section details the emissions inventories that were utilized as part of the SIL and NAAQS air quality modeling analyses.

2.1 PROJECT-WIDE EMISSIONS SUMMARY

For the SIL analysis, emissions from the new pathological waste incinerator (Model ID: INC8) were modeled as positive emissions and emissions from the existing pathological waste incinerator

(Model ID: INC4) were modeled as negative emissions for comparison with the SILs. Each of the incinerators were modeled at their potential to emit (PTE) emissions rates (Table 1).

Table 1 Project-Wide Emissions for Criteria Pollutants

Unit Designator Model ID Unit Description PTE (lb/hr)

PM PM10 PM2.5 SO2 NOX CO

EP S-4 INC4 Incinerator 4 1.70 1.70 1.70 0.55 2.18 2.20

EP S-21 INC8 Incinerator 8 1.20 1.20 1.20 7.6 1.38 2.50

2.2 FACILITY-WIDE EMISSIONS INVENTORY

As previously noted, the NO2 (1-hour), PM2.5 (24-hour) and SO2 (1-hour, 3-hour, 24-hour, and annual) project-wide emissions resulted in modeled ambient air concentrations greater than their respective SILs. Therefore, emissions inventories of Facility-wide sources were evaluated and

Facility-wide PTE emissions rates (Table 2) were modeled for comparison to the NAAQS.

2-2

Table 2 Facility-Wide Emissions Rates

Unit Designator Model ID Unit Description PTE (g/s)

PM10 PM2.5 SO2 NOX CO

EP-S-5 INC5 Incinerator 5 0.151 0.151 0.020 0.174 0.011

EP-S-21 INC8 Incinerator 8 0.151 0.151 0.958 0.174 0.315

S-16 CT2 Combustion Turbine #2 0.239 0.239 0.345 0.869 0.630

EP-S-10NG BLR1NG Boiler 1 – Natural Gas 0.077 0.032 0.309 0.667 0.354

EP-S-11NG BLR2NG Boiler 2 – Natural Gas 0.077 0.032 0.309 0.667 0.354

EP-S-1CNG BLR3NG Boiler 3 – Natural Gas 0.125 0.043 0.003 0.896 0.476

EP-S-20NG BLR4NG Boiler 4 – Natural Gas 0.125 0.043 0.003 0.896 0.477

EP-S-15NG BLR5NG Boiler 5 – Natural Gas 0.125 0.043 0.003 0.896 0.476

S-141 CATGEN1 Caterpillar 2060 kW Gen #1 0.348 0.011 0.126 5.255 2.103

S-181 CATGEN2 Caterpillar 2000 kW Gen #2 0.348 0.011 0.126 5.255 2.103

S-131 CATGEN4 Caterpillar 2060 kW Gen #4 0.348 0.011 0.126 5.255 2.103

S-171 CATGEN5 Caterpillar 2000 kW Gen #5 0.348 0.011 0.126 5.255 2.103

EP-S-191 CATGEN6 Caterpillar 2000 kW Gen #6 0.139 0.009 0.126 4.448 2.103

EP-61 B22GEN Building 22 Gen 0.176 0.015 0.052 3.306 0.249

EP-Freezer Farm1 FRFRGEN Freezer Farm Gen 0.003 0.001 0.001 0.828 0.042

EP-MB Gen1 MBGEN MB 500 KW Gen 0.009 0.002 1.341 1.676 0.131

EP-C31 C3GEN C-3 100 kW Gen 0.002 0.0005 0.001 0.336 0.030 1 The 1-hr NO2 and SO2 demonstrations did not include the presented emissions rates for the generators, as each is considered an intermittent source.

3-1

3. AIR QUALITY MODELING ANALYSIS APPROACH AND

TECHNICAL INFORMATION

This section contains information on the technical approach that was followed in the air quality modeling analysis, the air dispersion model selection, as well as the model options that were used.

The supporting information that was used in the air quality modeling analysis includes a building downwash analysis, meteorological data, and terrain data. The guidance provided in 40 CFR Part

51 Appendix W “Guideline on Air Quality Models” (U.S. EPA 2017) was used to conduct the air quality modeling analysis. Additional guidance provided in “Air Dispersion Modeling Guidelines

For Non-PSD, Pre-Construction Permit Applications” (Iowa DNR 2018) was incorporated.

3.1 AIR DISPERSION MODEL SELECTION

The current version (19191) of the American Meteorological Society/Environmental Protection

Agency Regulatory Model (AERMOD) air dispersion model was used to predict ambient air concentrations from the Facility. AERMOD is the 40 CFR 51 Appendix W preferred air dispersion model approved for refined regulatory modeling applications.

The AERMOD modeling system consists of two regulatory pre-processors and the dispersion model. AERMAP is the terrain pre-processor component and AERMET is the meteorological pre-processor component. The AERMAP pre-processor characterizes the surrounding terrain and generates receptor elevations. The AERMET pre-processor is used to generate an hourly profile of meteorological conditions and boundary layer characteristics.

The AERMOD air dispersion model contains user-selectable options that may be applied to a dispersion analysis for regulatory and non-regulatory applications. U.S. EPA has recommended that certain options be selected when performing air quality modeling analyses for regulatory purposes. The following regulatory default options were used in this air quality modeling analysis:

• Stack-Tip Downwash

• Accounting of Elevated Terrain Effects

• Calms Processing Routine

3-2

• Missing Data Processing Routine

• No Exponential Decay for Rural Mode

• Ambient Ratio Method 2 (ARM2)

3.2 RECEPTOR NETWORK

The receptor network used in the air quality modeling analysis covered a 10-kilometer (km) x 10-km square domain centered on the Facility. All receptors were referenced to the UTM coordinate system, Zone 15, using the North American Datum 83 (NAD83) projection. The receptor network had the following grid spacing:

• 50 m from the property boundary to ± 500 m

• 100 m from 500 m to ± 1.5 km

• 250 m from 1.5 km to ± 3 km

• 500 m from 3 km to ± 5 km

In addition to the main receptor grid, discrete receptors were placed along the property boundary at 50 m intervals. A plot of the receptor grid is shown in Figure 1.

Terrain elevations were assigned to all receptors using the current version of AERMAP (18081) and National Elevation Dataset (NED) files at 1/3 arc-second resolution in GeoTIFF format.

3-3

Figure 1 Receptor Network

3-4

3.3 METEOROLOGICAL DATA

The meteorological data for the air quality modeling analysis consisted of five years (2015-2019) of pre-processed AERMET meteorological data download from the Iowa Department of Natural

Resources (DNR) website. The version of AERMET used (19191) was the most-recent version available from Iowa DNR at the time of the analysis and included the Adjust u* option. The specified dataset for Story County includes surface meteorological data from Ames Municipal

Airport (KAMW – WBAN ID 94989) in Ames, and upper air meteorological data from the Omaha-

Valley Weather Service Forecast Office (KOAX – WBAN ID 94980) in Valley, Nebraska.

3.4 SOURCE CHARACTERIZATION

A summary of the physical stack characteristics for sources modeled in the air quality modeling analysis is provided in Table 3. Physical stack characteristics include stack dimensions and exhaust parameters. With the exception of the new pathological waste incinerator (model ID:

INC8), Boiler 1 (BLR1NG), and Boiler 2 (BLR2NG), which were modeled as capped point sources, each stack was modeled as an uncapped point source. All sources have stacks that vent in a vertical orientation.

3-5

Table 3 Stack Parameters

Unit Designator Model ID Stack Height (m)

Temperature (K)

Exit Velocity (m/s)

Stack Diameter (m)

EP-S-5 INC5 14.02 922.0 2.75 0.610

EP-S-21 INC8 15.24 1033.2 7.04 0.762

S-16 CT2 13.72 444.8 19.73 1.054

EP-S-10NG BLR1NG 14.02 449.8 10.59 0.610

EP-S-11NG BLR2NG 14.02 449.8 10.59 0.610

EP-S-1CNG BLR3NG 14.02 473.7 5.42 0.864

EP-S-20NG BLR4NG 14.02 449.8 17.37 0.813

EP-S-15NG BLR5NG 13.72 477.6 7.19 0.914

S-14 CATGEN1 10.67 787.6 21.77 0.406

S-18 CATGEN2 10.67 787.6 21.77 0.406

S-13 CATGEN4 10.67 787.6 21.77 0.406

S-17 CATGEN5 10.67 787.6 21.77 0.406

EP-S-19 CATGEN6 10.67 673.2 24.36 0.406

EP-6 B22GEN 7.32 790.9 16.59 0.305

EP-Freezer Farm FRFRGEN 2.01 868.2 47.79 0.152

EP-MB Gen MBGEN 2.69 739.8 81.16 0.152

EP-C3 C3GEN 1.98 816.5 43.40 0.102

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3.5 GOOD ENGINEERING PRACTICE STACK HEIGHT ANALYSIS

Stacks at the Facility were analyzed for the potential influence of building downwash on emissions and resulting ambient concentrations. Guidance contained in the U.S. EPA “Guideline for

Determination of Good Engineering Practice (GEP) Stack Height (Revised)” (U.S. EPA 1985) and the U.S. EPA Building Profile Input Program (BPIP) for PRIME (Version 04274) was followed.

The relevant structures and point sources included in the downwash analysis were digitized using geographic information system (GIS) software (Figure 2). The stack heights are less than GEP formula height; therefore, no stack height restriction is necessary in the air quality modeling analyses.

3.6 BACKGROUND AMBIENT AIR DATA

Ambient background concentrations were added to the model-predicted concentrations from the

Facility for comparison to NAAQS standards. Per Iowa DNR guidance, the following default rural background concentrations were applied for Story County:

• SO2 1-hour: 5 µg/m3

• SO2 3-hour: 5 µg/m3

• SO2 24-hour: 3 µg/m3

• SO2 Annual: 1 µg/m3

• PM2.5 24-hour: 20 µg/m3

• NO2 1-hour: 19 µg/m3

3.7 NITROGEN OXIDE TO NO2 CONVERSION

The stack emissions of NOX from the sources at the Facility will be primarily in the form of nitric oxide (NO), which is converted to NO2 in the atmosphere in the presence of background ozone

(O3). Assuming that all NOX that is emitted is converted to NO2 in the atmosphere is a conservative assumption that can be refined using methods that take atmospheric chemistry into account.

NCAH used U.S. EPA’s Ambient Ratio Method 2 (ARM2) in AERMOD to account for atmospheric conversion from NOX to NO2. The ARM2 option is an option that applies an

3-7 adjustment of modeled NOx concentrations based on a NO2/NOX in-stack ratio (ISR). NCAH utilized minimum and maximum ISRs of 0.1 and 0.9, respectively in the 1-hour NO2 modeling analysis. To justify the use of a non-default ISR, NCAH performed a review of U.S. EPA’s ISR database, which can be sorted by equipment class and fuel type to obtain ISR data provided from various sources, including Regional, State, and Local air permitting offices and industry trade groups. The database cites ISRs from 0.0001 to 0.0717, with an average of 0.0348, for natural gas-fired boilers, which account for the majority of non-intermittent NO2 emissions at the Facility.

The use of a 0.1 minimum ISR for Facility source represents a conservative and appropriate representation for the 1-hour NO2 modeling analysis.

3-8

Figure 2 Facility Layout

4-1

4. AIR QUALITY MODELING RESULTS

This section discusses the results from the air quality modeling analyses.

4.1 SIL AND NAAQS ANALYSIS

The significant impact analysis was initially performed to compare the model predicted, ground-level maximum concentrations from the project to the respective SILs (Table 4).

Table 4 SIL Analysis Results

Pollutant Averaging

Period

Class II

SIL

(µg/m3)

Modeled Concentration

(µg/m3)

Modeled Concentration Less

Than Class II SIL (Y/N)

CO

1-Hour 2,000 23.94 Yes

8-Hour 500 11.06 Yes

SO2

1-Hour 7.9 81.19 No

3-Hour 25 60.55 No

24-Hour 5 22.98 No

Annual 1 2.45 No

PM10 24-Hour 5 1.82 Yes

PM2.5

24-Hour 1.2 1.82 No

Annual 0.3 0.04 Yes

NO2

1-Hour 7.5 12.30 No

Annual 1 0.04 Yes

The significant impact analysis determined that the predicted maximum ground-level concentrations from the project were greater than the SIL for 1-hour NO2, 24-hour PM2.5, and 1-hour, 3-hour, 24-hour, and annual SO2. Facility-wide emissions for each of the pollutants above the SIL were evaluated for comparison to the NAAQS (Table 5). Model-predicted concentrations

4-2 for each of the evaluated pollutants were below the respective NAAQS thresholds, indicating the project does not cause or contribute to any predicted exceedances of NAAQS.

Table 5 NAAQS Analysis Results

Pollutant Averaging Period

NAAQS

(µg/m3)

Background (µg/m3)

Modeled Concentration

(µg/m3)

Total with Background

(µg/m3)

Modeled Concentration

Less Than

NAAQS (Y/N)

PM2.5 24-Hour 35 20 10.22 30.22 Yes

SO2

1-Hour 196 5 127.01 132.01 Yes

3-Hour 1,300 5 333.89 338.89 Yes

24-Hour 365 3 73.15 76.15 Yes

Annual 80 1 10.80 11.80 Yes

NO2 1-Hour 188 19 144.62 163.62 Yes