Guidance for Conducting Risk Assessments and Related Risk ...

CONTENTS
CONTENTS...........................................................................................................................................iii
TABLES .................................................................................................................................................v
FIGURES................................................................................................................................................v
ACRONYMS ........................................................................................................................................vii
EXECUTIVE SUMMARY.....................................................................................................................ix
1. INTRODUCTION ...............................................................................................................................1
1.1 PURPOSE AND SCOPE ...............................................................................................................2
1.2 AUDIENCE...................................................................................................................................3
1.3 IMPLEMENTATION ....................................................................................................................3
1.4 ROLES AND RESPONSIBILTIES................................................................................................4
1.5 DOCUMENT ORGANIZATION...................................................................................................4
2. ENVIRONMENTAL RESTORATION ...............................................................................................6
2.1 PROJECT RISK RANKING..........................................................................................................9
2.2 IMPLEMENTING THE RI/FS PROCESS ...................................................................................10
2.2.1 Site Evaluations.....................................................................................................................12
2.2.2 Remedial Investigation ..........................................................................................................13
2.2.3 Feasibility Study....................................................................................................................14
2.2.4 Deletion and Five Year Review .............................................................................................15
3. OTHER ENVIRONMENTAL MANAGEMENT ACTIVITIES.........................................................17
3.1 WASTE MANAGEMENT...........................................................................................................17
3.2 DECONTAMINATION & DECOMMISSIONING......................................................................17
3.3 TECHNOLOGY DEVELOPMENT AND DEMONSTRATION..................................................19
3.4 REINDUSTRIALIZATION.........................................................................................................19
4. RISK ASSESSMENT IMPLEMENTATION.....................................................................................20
4.1 DATA EVALUATION................................................................................................................21
4.2 EXPOSURE ASSESSMENT .......................................................................................................23
4.2.1 Characterization of the Exposure Setting: Land Use...............................................................24
4.2.2 Identification of Exposure Pathways......................................................................................25
4.2.3 Quantification of Exposure ....................................................................................................26
4.3 TOXICITY ASSESSMENT.........................................................................................................26
4.3.1 Toxicity Values .....................................................................................................................26
4.3.2 Toxicity Profiles....................................................................................................................27
4.4 RISK CHARACTERIZATION....................................................................................................27
4.4.1 Selecting Scenarios, Pathways, and Chemicals of Concern (COCs)........................................28
4.4.2 Verification of Calculations...................................................................................................29
4.4.3 Presenting the Risk Characterization Results .........................................................................29
4.5 UNCERTAINTY ANALYSIS .....................................................................................................29
5. SCREENING RISK ASSESSMENTS ...............................................................................................30
iii