Transportation-Related Air Toxics:
Case Study Materials Related to US 95 in Nevada

Revised Final White Paper
STI-902370-2308-RFWP

By:
Todd M. Tamura
Douglas S. Eisinger
Sonoma Technology, Inc.
1360 Redwood Way, Suite C
Petaluma, CA 94954-1169

Prepared for:
Michael Koontz and Michael J. Savonis, HEPN 10
U.S. Federal Highway Administration
Office of Natural Environment
400 7th Street SW
Washington D.C., 20590

March 7, 2003

ACKNOWLEDGMENTS

The authors thank Fred Lurmann, Hilary Hafner, Dr. Patrick Ryan, and Lyle Chinkin of STI for technical comments and advice, and Michael Koontz for providing technical direction as the FHWA project manager.

LIST OF FIGURES
LIST OF TABLES
ACRONYMS
EXECUTIVE SUMMARY

INTRODUCTION
1.1 Purpose
1.2 Report Organization
RELEVANT AIR TOXICS AND QUANTIFICATION OF CANCER RISKS
2.1 Identification of Relevant On-Road Mobile Source Air Toxics
2.2 Quantification of Cancer Risks from Air Toxics
2.3 Conclusions Regarding Important Air Toxics
AIR TOXICS AND REGIONAL AIR QUALITY
3.1 On-Road Mobile Sources as a Fraction of Regional-Scale Problems: Brief Citations from Example Literature
3.1.1 EPA National-Scale Air Toxics Assessments
3.1.2 California Air Resources Board Emissions and Air Quality Almanac
3.1.3 SCAQMD MATES-II Report
3.2 Review of the MATES-II Study
3.2.1 Fraction of MSAT Emissions from On-Road Mobile Sources
3.2.2 Monitoring Data and Risk Assessment
3.2.3 Comparison to Other Recent Southern California Research
3.2.4 Observations Concerning MATES-II vs. EPA DPM Risk Characterizations
3.3 Regional Emissions Trends
3.4 Summary Observations Concerning Mobile Sources and Regional Contributions to Air toxics
AIR TOXICS AND LOCALIZED AIR QUALITY
4.1 Background
4.2 Measurements of Concentrations as a Function of Distance from Roadways
4.3 MATES-II Data
4.3.1 Modeling Data
4.3.2 Discussion of MATES-II Monitoring Results Near Freeways
4.4 Epidemiological Studies
4.4.1 Observations Concerning the Denver, CO, Study
4.4.2 Observations Concerning Additional Epidemiological Literature
4.4.3 Summary Comments Concerning Epidemiological Literature
4.5 Overall Conclusions Regarding Localized Air Quality.
COMMENTS ON SIERRA CLUB CORRESPONDENCE
5.1 Applicability of MATES-II Findings to Las Vegas
5.1.1 Summary of MATES-II Findings
5.1.2 Criteria to Ascertain the Applicability of MATES-II Findings to Las Vegas
5.1.3 Consideration of Applicability Criteria
5.2 FINE PARTICULATE MATTER (PM_2.5)
5.2.1 Sierra Club Comments
5.2.2 Discussion of Comments
SUMMARY AND CONCLUSIONS
6.1 Regional Impacts from MSAT
6.2 Local Impacts from MSAT
6.3 Transferability of MATES-II Findings to Las Vegas.
6.4 Fine Particulate Matter (PM_2.5)
6.5 Summary Discussion of Issues Raised by the Sierra Club
6.5.1 Introduction
6.5.2 Discussion of Sierra Club Comments
REFERENCES