Section Three
TOXIC AND HAZARDOUS WASTES
29    APPLICATION OF RISK ASSESSMENT TO SELECTION
AMONG SITE REMEDIATION ALTERNATIVES
Eli J. Salmon, Director
Health, Safety and Risk Management
Intellus Corporation
Irvine, California 92715
Richard A. Brown, Technology Manager
Aquifer Remediation Systems
FMC Corporation
Princeton, New Jersey 08540
INTRODUCTION
The Environmental Protection Agency (EPA) mandated [1], that any remedial decisions and strategies related to hazardous substances be scientifically and technologically sound, economically efficient, and socially equitable. This calls for application of risk assessment/management methodologies
which the EPA's Administrator recognized [2] as the most important and most difficult role emerging
in the 1980's. It becomes necessary to develop well founded and consistent procedures as well as
uniform and coordinated approaches that enable deciding if, when, and how remediation of risks
arising from hazardous waste sites should be undertaken.
The definition of risk assessment/management by the National Academy of Sciences [3] distinguishes two components, namely:
1. The scientific exercise involved in the assessment of risks.
2. The political, economic, and social aspects of decision making about what action to
take.
In the simplest sense, risk assessment is the qualitative or quantitative characterization of potential
adverse impacts of particular substances or agents on individuals or populations. It is a function of
two measurable factors: hazard and exposure. Risk management, on the other hand, represents the
complex judgement and analysis that uses the results of risk assessment to provide a decision about
remediation.
In reality, the process of reaching a remediation decision is very complex because of the multitude
of considerations that must be optimized. They include:
1. Wide range of chemical and physical agents.
2. Many adverse effects including carcinogenic, mutagenic and teratogenic damages, systemic effects on various organs, and even psychological risks.
3. Various environmental impacts ranging from visibility impairment and crops damage to
ecosystem disruption.
4. Different routes of exposure.
5. Multitude of remediation technologies in different states of development.
6. Conflicting remediation objectives.
7. Diversified trade-offs among remediation alternatives.
8. Many uncertainties regarding hazards, environmental processes, and suitability of remediation options to particular projects.
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