API 4709 : 2001

RISK-BASED METHODOLOGIES FOR EVALUATING PETROLEUM HYDROCARBON IMPACTS AT OIL AND NATURAL GAS E&P SITES

American Petroleum Institute

More details

More info

Executive Summary
Part I: Introduction
Purpose of Manual
Content and Organization of Manual
Part II: Risk-Based Decision Making
What Is It?
Why Use It?
Traditional Approaches Not Based on Risk
Traditional Approaches May Misallocate Resources
Risk-Based Approaches Permit Cost-Benefit Analyses
Should It Be Used At All Sites?
What Are Tiered Risk-Based Decision-Making Frameworks?
When Is It Appropriate To Use a Tiered Approach?
What Is the Role of Generic Site Cleanup Criteria in the
Risk-Based
Decision-Making Process?
Tier 1 versus Tier 2 or Tier 3?
Part III: Characteristics of Crude Oils, Refined Petroleum
Products,
Condensates, and E&P Wastes
Chemical Characteristics
What Are the Chemical Characteristics of Crude Oil and Its
Refined Products?
Crude Oil
Refined Products
What Are the Chemical Characteristics of Condensates?
What Are the Chemical Characteristics of E&P Wastes?
Characterization Studies
Characterization Results
Physical Characteristics
What Are the Physical Properties of Hydrocarbons that Influence
their Movement in the Environment?
What Are the Nature of These Physical Properties for Crude Oil,
Refined Products, Condensates, and E&P Wastes?
Crude Oil
Refined Products Condensates
E&P Wastes
Toxicological Characteristics
What Human Health Toxicity Data Are Available?
Cancer Health Effects
Non-Cancer Health Effects
What Ecological Toxicity Data Are Available?
Summary of Key Differences in the Characteristics of Crude Oil,
Refined Petroleum Products, Condensates, and E&P Wastes
What Is the Evidence of Differences in Bulk Hydrocarbon Comp
Carbon-Number Range
Chemical Classes of Hydrocarbons
API Gravity
What Is the Evidence of Differences in Specific Chemical Comp
Benzene
PAHs
Metals
Blending Agents and Additives
What Is the Evidence of Differences in Mobility and Toxicity?
Mobility
Toxicity
Part IV: Calculation of Risk and Risk-Based Screening Levels
What Are the Key Components of the Four Elements of the Risk
Evalua-tion Process?
Hazard Identification
Exposure Assessment
Toxicity (Dose-Response) Assessment
Risk Characterization
What Calculations Are Used To Determine Risks to Human Health?
Exposure Assessment: Calculation of Contaminant Intake
Derivation of Toxicological Dose-Response Factors
Calculation of Risk
What Are Risk-Based Screening Levels (RBSLs) and How Are They
Derived?
Are RBSLs Identical for All Routes of Exposure?
What Are the Default Assumptions That Are Used in the RBSL
Equations and from Where Did They Originate?
Part V: Application of Risk-Based Methodologies to E&P Sites
TPHCWG Risk-Based Methodology
What Is the Traditional Approach for Managing
Hydrocarbon-Impacted Soils at E&P Sites?
What Is Total Petroleum Hydrocarbon or TPH?
What Methods Are Used to Measure Bulk TPH in Soil and
Ground-water?
Analytical Methods
Shortcomings
What Does Industry Guidance Tell Us About TPH Closure
Criteria?
What Are Some of the Typical TPH Closure Criteria that
Have Been Used Internationally?
What Other Criteria Besides TPH Have Been Used for the
Closure of E&P Sites?
What Is the Role of Bulk TPH Measurements in E&P Site
Manage-ment?
What Is the General Risk Assessment Approach of the TPHCWG and
How Does It Address the Shortcomings of Bulk TPH Measurements?
Cancer Risk
Non-Cancer Risk
What Basis did the TPHCWG Use To Define the Different
Hydro-carbon
Fractions of TPH?
How Was the Toxicity of Each Hydrocarbon Fraction Assigned?
What Analytical Methodology Is Used by the TPHCWG To Quantify
these Hydrocarbon Fractions?
Why Was It Necessary To Modify the TPHCWG Analytical
Methodology To Deal with Crude Oil at E&P Sites?
How Was the TPHCWG Analytical Methodology Modified To Deal
with Crude Oils at E&P Sites?
What Portion of the Total Hydrocarbon in Crude Oil Can Be
Categorized Using the Modified TPHCWG (PERF) Analytical
Metho-dology?
How Do the Quantity of Hydrocarbons in Each Fraction Vary Among
Different Crude Oil Products?
How Were the Fate and Transport Properties and Toxicological
Characteristics of the C35-44 and C44+ Carbon Number Fractions
Determined?
C35-44 Carbon Number Fraction
C44+ Carbon Number Fraction
What Are Relevant Exposure Pathways for an E&P Site?
How Are the TPH Fractionation Data Used To Calculate an RBSL for
the Whole Crude Oil?
What Exposure Scenarios and Pathways Are Important for Crude Oil
and What Are the TPH RBSLs for these Situations?
What Exposure Pathways and TPH Fractions Typically Dictate TPH
RBSLs for Crude Oil at an E&P Site?
How Do the TPH RBSLs for Crude Oil Compare to TPH RBSLs for
Refined Petroleum Products, Condensates or Associated Wastes?
Refined Petroleum Products
Gas Condensates
Associated Wastes
When Is It Necessary To Use the Risk-Based Assessment of TPH
Rather than Conventional TPH Measurements or Assessments?
How Important Are the Risks Associated with Metals, Polycyclic
Aromatic Hydrocarbons, and Benzene in the Crude Oil?
Metals
Polycyclic Aromatic Hydrocarbons
Benzene
RBCA Tools for the E&P Industry
Other Considerations for Overseas Applications
Has the TPHCWG Methodology Been Accepted by Overseas
Regulators?
What Special Factors Should Be Considered When Preparing To
Apply the TPHCWG Methodology to an International E&P Site?
Part VI: References
Appendix A - E&P Wastes: Regulatory Status
Appendix B - Equations for Calculation of Risk-Based Screening
Levels for Soil
Appendix C - Consideration of Hydrocarbon-Saturated Soil
Conditions During Calculation of RBSLs

Abstract

Defines the process of calculating human health risk-based screening levels for total petroleum hydrocarbons (TPH) in an easy-to-understand question and answer format.