Contents and Executive Summary

Fixed Site (Regional) Program

     A. Monitoring

     B. Modeling

Microscale Program

Caveats and Risk Uncertainty

ES-7

Chapters

1. Introduction

1-1

2. Historical Trends in Toxic Air Contaminants and
    Associated Cancer Risks in the South Coast Air
    Basin and Vicinity

2-1
 

     2.1 Summarized Highlights

     2.2 Discussion

3. MATES II Monitoring Program

     3.1 Site Location and Monitoring

3-1

     3.2 Findings

        3.2.1 Intersite Comparisons, Concentrations

3-4

        3.2.2 Cancer Risk – Uncertainty in Risk
                Assessment

3-5

        3.2.3 Intersite Comparison Cancer Risk

3-6

        3.2.4 Seasonal Variability

3-13

        3.2.5 Species and Source Apportionment

3-20

4. Emission Inventory Development

4-1

     4.1 On-Road Mobile Sources

4-1

     4.2 Stationary Point Sources

4-1

     4.3 Area and Off-Road Sources

4-2

     4.4 Summary of Toxic Emissions

4-3

5. Regional Model Evaluation

5-1

     5.1 3-Dimensional Simulation Models Evaluated

     5.2 Toxic Compounds Modeled and Model
           Performance Goals

     5.3 Model-Estimated Spatial Concentration
           Fields

     5.4 Risk Assessment Calculations

     5.5 Conclusion

5-9

6. Microscale Study

     6.1 Introduction

     6.2 Site Selection Process

     6.3 Analytical Approach

6-4

     6.4 Monitoring Results and Findings

6-4

          6.4.1 Microscale-Fixed Site Comparisons

          6.4.2 Mobile/Stationary Source Influences

     6.5 Emissions Inventory

     6.6 Local-Scale Modeling

6-17

7. Findings and Conclusions

7-1

     7.1 Monitoring Program

     7.2 Modeling

     7.3 Microscale Program

7-2

     7.4 Caveats and Uncertainties

8. References

8-1

9. Response to Comments

9-1

Appendices

Cover; Governing Board; Contributors; List of Appendices

    I-A    List of Toxic Compounds and Their
            Associated Unit Risk Factors (URF)

    I-B    List of Air Toxic Study Technical Review
            Group (ATSTRG) Members

    II      Historical Trends in Toxic Air Contaminants
            and Cancer Risk in the South Coast
            Air Basin

    III-A  Protocol,
           Environmental Justice Initiative Number 2,
           Monitoring and Laboratory Analysis

    III-B  Statistical Summary for the MATES-II
           Fixed Monitoring Sites

    IV    1998 Emissions by Major Category

    V     Air Toxic Regional Modeling

    VI    Details of Microscale Study

              Location of Sites

              Wind Roses

              Emissions

              Microscale-Fixed Site Comparisons

              Modeling Results