13    QUANTITATIVE RISK ASSESSMENT AS A DECISION TOOL
FOR HAZARDOUS WASTE MANAGEMENT
Daniel Kofi Asante-Duah, Project Engineer
Environmental Resources Management, Inc.
Exton, Pennsylvania 19341
INTRODUCTION AND BACKGROUND
Waste production is an inevitable characteristic of an industrial society. The effective management
of hazardous wastes has become an important environmental priority and will be a growing social
challenge for years to come. But it has also become evident that the proper management of hazardous
wastes poses great challenges. Risk assessment seems to be one of the fastest evolving tools for
developing appropriate management decisions.
What Is Risk Assessment?
Several definitions of risk assessment have been published in the literature by various authors1"5 in
describing their risk assessment models. In a very generic sense, risk assessment may be considered "a
systematic tool for making estimates of all the significant risk factors that may prevail over an entire
range of failure modes and/or exposure scenarios."
Risk assessment is a powerful tool for developing insights into the relative importance of the
various types of facility loading conditions, failure modes and/or exposure scenarios from facility
failures and source releases. The risk assessment process is a mechanism that utilizes the best available
scientific knowledge to establish case-specific responses that will ensure most justifiable and defensible decisions on hazardous waste management.
Why Risk Assessment?
Because of the health, environmental and economic implications of hazardous waste problems,
decisions relating to hazardous waste management should be based on a systematic and scientifically
valid process. It is apparent that risk assessment provides one of the best mechanisms known for
estimating risks posed by hazardous wastes.6 Risk assessment can provide meaningful inputs and
justifications for the difficult task of selecting measures needed to reduce the likelihood of failure and
the unpalatable consequences that result. Also, quantifying health risks associated with exposure to
toxicants emanating from hazardous waste sites aids in decision-making for hazardous waste
management.
Risk Assessment Goals
A major goal in a risk assessment process is to identify failure modes and scenarios that will help
work out methods to reduce the probability of failure and the attending human, economic, and
environmental losses of any failure event. Also, through probabilistic modeling and analyses, uncertainties can be assessed properly and their effects on a given decision accounted for systematically. In
this manner the risk associated with given decision alternatives may be delineated and then appropriate corrective measures taken accordingly.
The overall purpose of risk assessments is to provide a complete information set to risk managers,
so that the best possible decision can be made concerning a hazardous problem.
44th Purdue Industrial Waste Conference Proceedings, © 1990 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Printed in U.S.A.
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