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AMI is in the forefront of air quality impact assessment with extensive experience in dispersion modeling, emission inventory and control, meteorological, air quality data analysis, permit application and EIR/EIS preparation. AMI has considerable experience in the application of air quality models approved by regulatory agencies. AMI has also developed advanced models for photochemical pollutants and complex terrain that have received approval from regulatory agencies, e.g. the inert pollutant model OCDCPM for point source modeling in complex terrain and coastal areas, and the photochemical trajectory model TRACE.

Advanced models operational on AMI's in-house computers include the inert models AERMOD and CALPUFF; the mesoscale meteorological models MM5 and WRF; and the photochemical models CAMx, CMAQ, TRACE, UAM and WRF/Chem. In addition, AMI has developed and implemented several processors that allow the efficient generation of modeling inputs (emissions, meteorology and air quality) and computer visualization of modeling results. AMI has developed a PC-based regional modeling system named SMART (System for Modeling Atmospheric Release and Transport) that is operational on Linux-based PCs with symmetric multiprocessors (SMP) that have been shown in benchmark tests to be an excellent alternative to expensive UNIX workstations. Representative air quality studies performed by AMI include the following:

Review of the PM2.5 Attainment SIP for the Liberty-Clairton Non-Attainment Area

AMI completed a comprehensive review of the modeling analyses performed for the PM2.5 attainment demonstration for the Liberty-Clairton area  in Pennsylvania. For the Clean Air Council, this review focused on the meteorological inputs generated by the mesoscale WRF model and the predictions of the photochemical grid model CMAQ, Deficiencies of the modeling analyses as well as emissions controls have been identified.

Photochemical Modeling of a High PM2.5 Episode in China

AMI performed a comprehensive modeling study that uses the WRF/Chem model to simulate a high PM2.5 episode that occurred in December 2015  in Beijing, China.  Meteorological inputs are generated by the mesoscale model WRF. Emissions from the HTAP-EDGAR database with a fine resolution of 0.1 degree have been processed  for input to the WRF/Chem model. The performance of WRF/Chem was evaluated against available monitoring data. Emissions control scenarios and major source contributions were also analyzed. A presentation of the WRF/Chem simulation for the base case is available here.

Air Quality Impact Analysis of Proposed Morrow Pacific Coal Export Terminal

In late 2012, AMI performed detailed air quality modeling of impacts from both onshore and overwater emissions sources associated with the proposed coal export terminal in Oregon. The AERMOD model was used to model 1-hour NO2 impacts, including both Tier 3 techniques PVMRM and OLM, from trains, barges and ocean-going vessels. Annual and 24-hour PM2.5 impacts were also analyzed, including open trains. 

Wind Field Modeling for Pesticide Releases in Oregon

AMI applied the mesoscale model WRF to simulate the winds and transport conditions during releases of pesticide by helicopters. This modeling was used to assess impacts of these pesticide releases on a nearby vineyard in Oregon.

SO2 Impacts of Existing Coal Plants

In June 2010. a new 1-hour SO2 national ambient standard of 196 ug/m3 has been promulgated by US EPA. AMI applied the AERMOD model to assess compliance of this standard for several coal-fired power plants throughout the US, including Big Brown, Boswell, Danskammer, Monticello, Rivesville, Shawville, Sherbune, Titus and Willow. The preprocessor AERMET was used to generate new 5-year meteorological data that include ASOS wind measurements. SO2 impacts were modeled for both maximum allowable emissions in the plant permit and maximum actual emissions derived from the US EPA Clean Air Market database. 

Photochemical Modeling for Existing and Proposed Coal Plants in China

AMI performed a comprehensive modeling study that uses the Community Multiscale Air Quality  (CMAQ) model to analyze the impacts of ozone, fine particles (PM2.5) and air toxics in eastern China from existing and proposed coal plants. Cumulative impacts are modeled for recent high PM2.5 episodes in January 2013.  Meteorological inputs are generated by the mesoscale model WRF. Emissions from the NASA INTEX-B database have been updated  for input to the CMAQ model. The performance of both CMAQ and WRF are evaluated against available monitoring data. Emissions control scenarios and major source contributions are also analyzed.

Photochemical Modeling for Existing and Proposed Coal Plants in Texas

AMI completed three modeling studies that used the Comprehensive Air Quality Model with Extensions (CAMx) to analyze the impacts of ozone, fine particles (PM2.5) and visibility in neighboring states (Arkansas, Louisiana and Oklahoma) from the existing and proposed coal plants in Texas. Cumulative impacts were modeled for the entire year 2002 using the modeling database developed by CENRAP for regional haze modeling.  Visibility impacts were analyzed at Federal Class I areas such as Upper Buffalo in Arkansas and Wichita Mountains in Oklahoma.

Cumulative Ozone Impact Modeling for Existing and Proposed Coal Plants in Texas

AMI has recently completed three modeling studies that used the Comprehensive Air Quality Model with Extensions (CAMx) to analyze the ozone impacts in neighboring states from the existing and proposed coal plants in Texas. Cumulative ozone impacts were modeled using recent ozone episodes that occurred in neighboring states (Arkansas, Louisiana and Oklahoma) and were used in the State Implementation Plans (SIP). 

Ozone Impact Modeling for Proposed Coal Plant in Texas

AMI completed a modeling study using the Comprehensive Air Quality Model with Extensions (CAMx)  for the proposed White Stallion coal-fired power plant near Houston, Texas. Two CAMx runs were performed for a 2005 ozone episode: the baseline and the baseline with the White Stallion project. Project ozone impacts were computed as the differences between the two model runs.

Photochemical Modeling for Power Plant Siting in Arizona and California

AMI completed two modeling studies using the Urban Airshed Model (UAM) for power plant siting. In the first study for the proposed High Desert Power Project, several UAM runs were performed using the September 7-9, 1987 episode in the South Coast Air Basin to construct an ozone isopleth diagram. The ozone isopleths were then used to derive a suitable VOC/NOx interpollutant tradeoff ratio.

The second study involved an assessment of potential impact from power plant emissions on ozone air quality in the Phoenix, Arizona metropolitan area. AMI has developed an efficient program that allows the treatment of power plant concentrations predicted by the ISCST3 dispersion model as UAM boundary conditions. Using the July 1996 episode that was first used by AMI in the UAM model evaluation, incremental and cumulative ozone impacts were predicted by UAM for two proposed power plants that will be located west of Phoenix.
 

Air Quality Impact Modeling for Compressor Station in the Marcellus Shale Region

AMI has recently completed a modeling study using the AERMOD model for the Barto compressor station in Pennsylvania. NOx emissions from the compressors during fracturing operations have been analyzed using EPA-recommended  modeling techniques, including the Tier 3 PVMRM method. Modeling results show that the 1-hour NO2 ambient standard of 188 ug/m3 is largely exceeded by all modeling techniques. More information, including a copy of the AERMOD modeling report,  is available at     http://www.cleanair.org/program/outdoor_air_pollution/marcellus_shale/marcellus_shale_compressor_station_exceeding_pollution   

Review of PSD Permits for Proposed Coal-Fired Power Plants  

AMI completed a review of the air quality and visibility impact  analysis submit as part of PSD Permit Applications for several proposed coal-fired power plants throughout the US,  including Georgia (Longleaf and Plant Washington), Kentucky (Kentucky Syngas and Trimble), Michigan (Consumers Energy and Wolverine), Nevada (Ely), Montana (Highwood), New Mexico (Desert Rock), Ohio (AMP), South Dakota (Hyperion), Virginia (Dominion) and Wyoming (Dry Fork and Medicine Bow Fuels). For these facilities, in addition to reviews, AMI also performed dispersion modeling:  the AERMOD model  for NAAQS and PSD analyses in PSD Class II areas, and CALPUFF modeling for long-range transport to the nearest PSD Class I areas. Visibility impact analysis was based on the FLAG and BART procedures recommended by the US EPA and Federal Land Managers.  Khanh Tran of AMI  has also been deposed and performed expert testimony in legal challenges to the PSD permits of several coal-fired power plants (AMP, Dry Fork, Highwood and Longleaf).  

Air Quality & Visibility Impact Analysis for  a Proposed Coal-Fired Power Plant  

AMI recenlty completed a review of the air quality and visibility impact  analysis for a proposed coal-fired power plant  in Trimble County, Kentucky. AMI also performed CALPUFF modeling for long-range transport to the nearest PSD Class I area, Mammoth Cave National Park. Wind fields were generated for the year 1996 by the preprocessor CALMET using inputs from the mesoscale model MM5. Potential visibility impacts were analyzed by the postprocessor CALPOST based on the FLAG procedures recommended by the US EPA and Federal Land Managers.

 
Air Quality Impact Analysis for Rail Consolidation in Reno

AMI has completed in early 2000 a modeling analysis of potential air quality impact for the proposed rail consolidation in Reno, Nevada. Construction impacts were analyzed with the ISCST3 model. The line source CALINE4 model was used for both rail and vehicular traffic impacts. Several project alternatives were analyzed, including an analysis of net air quality benefits from vehicular traffic as a result of the proposed rail consolidation.
 

Air Quality Impact Analysis for  Los Angeles Generating Stations  

AMI completed dispersion modeling and health risk assessments for power plants operated by Los Angeles Department of Water and Power (LADWP) in Los Angeles County. The  model ISCST3 was used for dispersion modeling for both criteria pollutants and air toxics, and the HARP model for multipathway health risk assessment. These modeling efforts are part of the permit applications for these facilities.

Regional Meteorological Modeling for Photochemical Modeling in the San Diego Air Basin

For San Diego County, AMI performed in 2003 a comprehensive modeling study that used the state-of-the-art mesoscale model MM5 for generating three-dimensional wind fields and other meteorological inputs for photochemical grid modeling with the CAMx model. The non-hydrostatic MM5 model was applied to the August 3-7, 1997 ozone episode that occurred during the Southern California Ozone Study (SCOS97).  Meteorological fields predicted by MM5 such as winds and temperature have been compared against actual field measurements, and the MM5 performance has been evaluated  using both graphical statistical techniques.

Meteorological and Photochemical Modeling of Large-Scale Albedo Changes in the Los Angeles Air Basin

Under contract to Southern California Edison, AMI performed a modeling study to assess the effectiveness of large-scale albedo changes as an innovative ozone control strategy. AMI adapted the state-of-the-art mesoscale model MM5 for predicting the potential temperature changes and generating three-dimensional wind fields for photochemical grid modeling. The non-hydrostatic MM5 model was applied to the August 26-28, 1987 ozone episode which occurred during the Southern California Air Quality Study (SCAQS) in the South Coast Air Basin. AMI also developed software to interface between MM5 and the photochemical grid model UAM. The MM5 and UAM models were applied to simulate both the base case and the scenario with maximum surface albedo modifications derived from a satellite-based land use database.
 

Comparison of Wind Field Models in the Los Angeles Air Basin

AMI performed a comparative study of state-of-the-art models capable of generating three-dimensional wind fields used in photochemical grid modeling. The models used in this study include: the diagnostic DWM model, the prognostic CSUMM model, and the MMFDDA model. Developed by AMI, the MMFDDA is based on CSUMM with the capability of four-dimensional data assimilation of actual field measurements. The wind models were applied to the August 26-28, 1987 ozone episode which occurred during the Southern California Air Quality Study (SCAQS) in the South Coast Air Basin. Results of the UAM photochemical modeling using the generated wind fields are used to assess the accuracy of wind models.

AMI has developed a PC-based regional modeling system named SMART (System for Modeling Atmospheric Release and Transport) that is based on UAM and CSUMM. Benchmark tests of these models on both UNIX workstations and Pentium-based PCs have been conducted by AMI and described in a recent publication. Test results show that Pentium-based PCs are competitive in terms of execution times with UNIX workstations yet are several times cheaper. In addition, multiple model runs, especially those required for control strategy development, can be performed simultaneously using several PCs available at the office.
 

Photochemical Modeling Training and Support

Under contract to the Santa Barbara County APCD, AMI provided training and support to the District staff in the application of the photochemical grid model UAM and the mesoscale prognostic model CSUMM. These models have been applied to the September 5-7, 1984 ozone episode which occurred in the Santa Barbara-Ventura area during the 1984 SCCCAMP field program. Modeling software was installed on a PC with an Intel 860 coprocessor board.
 

Photochemical Modeling for Phoenix Ozone Management Plan

For the State of Arizona Department of Environmental Quality, AMI performed photochemical modeling with the Urban Airshed Model (UAM) for the development of an Voluntary Early Ozone Plan (VEOP) for the Phoenix metropolitan area. The UAM model was applied to simulate two multi-day ozone episodes occurring in August 1992 and July 1996. Following the successful performance evaluation of the base cases, the UAM model was used to assess the effectiveness in reducing ozone in 1999 and 2010 of several control strategies including reformulated fuels and vehicular inspection & maintenance programs. AMI also provided training to ADEQ staff in using the UAM and its preprocessors.
 

Performance Evaluation of A Nested Photochemical Grid Model

For Southern California Edison, AMI recently conducted a comprehensive evaluation of two photochemical grid models: UAM and UAMFEM. Developed by AMI, the UAMFEM model is a finite element version of UAM that allows the use of variable or nested grids to enhance modeling accuracy and computer efficiency. Both models were applied to the SCAQS August 26-28, 1987 which occurred in the Los Angeles air basin.
 

Air Quality Analysis of Proposed Offshore Oil and Gas Development Projects

From 1982 to 1988, AMI successfully completed detailed air quality impact analyses of several development projects proposed by major oil companies in the Santa Barbara Channel and Santa Maria Basin of southern California. These studies were part of comprehensive EIS/EIRs prepared for Federal, State and local government agencies including the DOI Minerals Management Service, U.S. Army Corps of Engineers, California State Lands Commission, California Coastal Commission and Counties of Santa Barbara, San Luis Obispo and Ventura. Inert pollutant impacts were analyzed with Gaussian-based models such as OCD, ISCST, MPTER, COMPLEX I, COMPLEX II and the AMI-developed OCDCPM model. Onshore ozone impacts were assessed with the AMI-developed trajectory model TRACE and the three-dimensional Urban Airshed (UAM) and PARIS grid models.
 

Development and Application of A Dispersion Model for Complex Terrain and Coastal Environments

Under guidance from regulatory agencies (including EPA Region IX, California Air Resources Board and Santa Barbara County APCD), AMI developed the inert pollutant model OCDCPM. This model combines three models (OCD, COMPLEX I and MPTER) and is designed for point source modeling in complex terrain and coastal areas. The OCDCPM model has been used extensively by AMI and others in several offshore oil and gas development projects throughout California.
 

Air Quality and Visibility Impact Analysis of Coal Resources Development

As part of an EIS prepared by the DOI Bureau of Land Management, AMI applied the long-range transport model MESOPUFF and the visibility model VIRAD to assess regional effects from proposed development of coal mines and end-use facilities in the Fort Union Coal Region of North Dakota and Montana.
 

Air Quality and Odor Impact Analysis for Oil Refinery Expansion

As part of an EIR prepared by the City of Long Beach, California, AMI was responsible for a modeling analysis of air quality and odor impacts from the expansion of an existing oil refinery. Air quality impacts were analyzed with the ISC and CDM models. A fluctuating plume-puff dispersion model developed by AMI was used to predict the frequency and magnitude of odor impacts in neighboring communities.
 

Development of An Air Quality Model for Slash Burning Operations

For Weyerhaueser Corporation, AMI adapted the three-dimensional grid model IMPACT for air quality analysis of slash burning operations in the mountainous regions of the Pacific Northwest. The model was also evaluated against actual measurements collected during intensive field programs.
 
 
 

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