TECHNICAL BACKGROUND DOCUMENT
POPULATION RISKS FROM INDIRECT EXPOSURE PATHWAYS, AND POPULATION EFFECTS FROM EXPOSURE TO AIRBORNE PARTICLES FROM CEMENT KILN DUST WASTE
Office of Solid Waste
U.S. Environmental Protection Agency
August 1997 (Note: original document states: "Draft, Do Not Cite or Quote")

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TABLE OF CONTENTS

CHAPTER 1 INTRODUCTION AND OVERALL FINDINGS........................ 1-1
1.1 Introduction ................................................. 1-1
1.2 Overall Findings .............................................. 1-2

CHAPTER 2 POPULATION RISKS FROM INDIRECT EXPOSURE PATHWAYS ................ 2-1

2.1 Background and Scope ......................................... 2-1
2.1.1 Starting Point of this Analysis ...............................2-I
2.1.2 What is Included and Excluded from the Scope of this Analysis .......2-3
2.2 Summary of Population Risk Assessment Framework ....................2-4
2.2.1 The Risk Scenario Being Assessed ............................2-4
2.2.2 The General Approach for Assessing the Risk Scenario .............2-8
2.3 Summary of Overall Approach ....................................2-9
2.3.1 Tier 1: Screening Analysis ................................2-10
2.3.2 Tier 2: Detailed Analysis ..................................2-10
2.4 Results....................................................2-16
2.4.1 Results of the Tier 1 Analysis ..............................2-16
2.4.2 Results of the Tier 2 Analysis ................ . .............2-18
2.4.3 Results Extrapolated to Full Universe .........................2-24
2.5 Major Limitations and Uncertainties ...............................2-27
2.5.1 Limitations and Uncertainties for the Indirect Exposures Analysis..........................2-27
2.5.2 Alternative Approach to Calculate Population Risks and Associated Limitations ............................2-31

CHAPTER 3. POPULATION EFFECTS DUE TO PM EXPOSURES ............................ 3-1
3.1 Background and Scope ......................................... 3-1
3.1.1 Starting Point of this Analysis ...............................3-1
3.1.2 What is Included and Excluded from the Scope of this Analysis ....... 3-2
3.2 Summary of Overall Approach .................................... 3-3
3.2.1 Identify An Appropriate "Risk Descriptor" for PM Exposures ......... 3-3
3.2.2 Develop the Overall Modeling Framework ...................... 3-3
3.2.3 Select Model(s) for Estimating Emissions and Dispersion ............ 3-6
3.2.4 Determine Sources of Emissions ............................. 3-8
3.2.5 Identify and Develop Data for Modeling Inputs ................... 3-9
3.2.6 Select Facilities for Modeling .............................. 3-14
3.2.7 Define Exposure Points .................................. 3-16
3.2.8 Model Emissions and Dispersion and Characterize Populations Effects ......................... 3-16
3.3 Results.................................................... 3-17
3.3.1 Emissions from Selected Facilities ........................... 3-17
3.3.2 Ambient PM Concentrations and Exposed Populations at the Highest-Emitting Facility ............................ 3-18
3.3.3 Exposed Populations at 52 Cement Plants Examined .............. 3-20
3.3.4 Exposed Populations at All Cement Plants ..................... 3-22
3.4 Major Limitations and Uncertainties . . . ............................ 3-37

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APPENDICES

A: Exposure Parameter Values Used for CKD Risk Assessment ............... A-1
B: Individual Risk Estimates from RTC and NODA ........................ B-1
C: Results of the Tier 1 Screening Analysis ............................. C-1
D: Facility-Specific Raw Data and Calculations, Fish Ingestion Pathway ......... D-1
E: Example of Facility-Level Raw Data, Vegetable Ingestion Pathway .......... E-1
F: Equations and Background Information from AP-42 ..................... F-1
G: Comparison of Previous and Current Modeling of Particulate Matter at Two Cement Plants ..................................... G-I

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