1 Neighborhood Assessment: Technical Issues to be investigated in the Wilmington Air Quality Study Vlad Isakov Todd Sax May 06, 2003 California Air Resources Board

2 Neighborhood Assessment Neighborhood Assessment Program: –to develop and test methodologies for evaluating the impacts of air pollution on a neighborhood scale. First study: Barrio Logan project –Barrio Logan Modeling Protocol Discussed previously Peer reviewed in July 2001 Second: Wilmington Air Quality Study (WAQS)Second: Wilmington Air Quality Study (WAQS) –Developing new protocol specific to Wilmington Improvements based on lessons learned in Barrio Logan Improvements based on lessons learned in Barrio Logan Protocol expanded for improved model evaluation Protocol expanded for improved model evaluation May 6, 2003California Air Resources Board

3 Status of Barrio Logan May 6, 2003California Air Resources Board Emissions –Microscale inventory completed Modeling –Microscale Modeling Microscale modeling completed –Point / area sources (ISCST3) –Mobile sources (CAL3QHCR) Tracer study –Regional Modeling Regional modeling completed (CALGRID, CMAQ) Integration of Model ResultsIntegration of Model Results In progress In progress

4 Summary of Technical Issues May 6, 2003California Air Resources Board Emissions –Spatial and temporal allocation –Data accuracy Modeling –Microscale Modeling Model selection –Point / area sources (ISCST3, AERMOD, CALPUFF) –Mobile sources (CALINE, ISCST3, AERMOD) –Regional Modeling Model selection (CALGRID, CMAQ, CAMx) Time period modeled (meteorology / averaging procedure) Run-time / disk space Spatial resolution (4km) Integration of Model ResultsIntegration of Model Results Double counting Double counting

5 Why Wilmington? May 6, 2003California Air Resources Board Identified as one of the communities most impacted by air pollution in the Los Angeles region by the SCAQMD in Located in close proximity to major freeways, ports, petroleum refineries, and other sources. Neighborhood sources located in close proximity to residential areas.

6 Wilmington Modeling Domain May 6, 2003California Air Resources Board

7 Status of Wilmington May 6, 2003California Air Resources Board Developing Protocol (In-progress) Developing Inventory (In-progress)

8 Microscale Inventory: Lessons Learned from Barrio Logan May 6, 2003California Air Resources Board Point SourcesPoint Sources –Most neighborhood sources not a concern –Near source impacts could be an issue –Stack data are required - often limited On-Road SourcesOn-Road Sources –Travel demand models Not all roadways covered Not all roadways covered Spatial resolution is limited Spatial resolution is limited Vehicle volume and classification - general assumptions Vehicle volume and classification - general assumptions –Need to account for all roadway emissions in microscale Off-Road SourcesOff-Road Sources –Need to account for off-road emissions in microscale

9 Microscale Inventory: Methodology for Wilmington May 6, 2003California Air Resources Board Industrial and Commercial Facilities - ExpandedIndustrial and Commercial Facilities - Expanded –Large facilities Multiple inventory data sources and on-site surveys Multiple inventory data sources and on-site surveys –Neighborhood Sources On-site surveys On-site surveys On-Road Sources - more detailedOn-Road Sources - more detailed –Enumerate and assess assumptions –Sensitivity studies and comparison to vehicle counts Off-Road Sources - major focusOff-Road Sources - major focus –Bottom-up inventory, all source categories at port –On-site surveys

10 Emissions: Industrial and Commercial Facilities 405 facilities-toxics / 259 -criteria 170 surveyed facilities Enhanced QA/QC in progress Review by SCAQMD and selected facilities in progress. On-Road Emissions Link-Based Inventory (>2000 links) Evaluation in progress Marine Terminals and Related Off-Road Port-specific inventories Microscale Inventory: Sources in Wilmington May 6, 2003California Air Resources Board

11 Model Evaluation in Wilmington May 6, 2003California Air Resources Board –Sensitivity studies –Tracer studies (to ensure models provide reliable estimates) Near-field (<50m) (done previously) Near-field (<50m) (done previously) Local-scale (50m - 2 km) Local-scale (50m - 2 km) –ground level release (done previously) –Wilmington - elevated (stack) release. Scheduled for –Supplemental short-term monitoring –Uncertainty analysis Gasoline Stations Gasoline Stations Diesel PM in modeling domain Diesel PM in modeling domain

12 Wilmington: Lessons Learned So Far... Industrial and Commercial FacilitiesIndustrial and Commercial Facilities –90% tox-weighted emissions (from facilities) Cancer: diesel PM, CrVI, 1,3 butadiene, benzene, cadmium. Cancer: diesel PM, CrVI, 1,3 butadiene, benzene, cadmium. Chronic: 12 pollutants Chronic: 12 pollutants –Complex point sources - neighborhood scale risk –On-site mobile source emissions contribute to traditional point source facility risk –Neighborhood sources - potential near-source risk gasoline stations, dry cleaners, small complex point sources gasoline stations, dry cleaners, small complex point sources –Need correct emissions locations –Stack data are limited - defaults must be assigned May 6, 2003California Air Resources Board

13 Continuing Work EmissionsEmissions –Better understand accuracy and uncertainty What spatial resolution can be achieved? What spatial resolution can be achieved? –Identify “sources that matter” Reduce resource requirements for future applications Reduce resource requirements for future applications ModelingModeling –Microscale Tracer study - evaluate model choice for stack-type releases Tracer study - evaluate model choice for stack-type releases Toxics monitoring - help interpret model results Toxics monitoring - help interpret model results Uncertainty analysis - understand how assumptions affect model results Uncertainty analysis - understand how assumptions affect model results –Regional and Integrated Model Results Double counting - ensure reliable model predictions Double counting - ensure reliable model predictions May 6, 2003California Air Resources Board