76    IMPROVED MANAGEMENT OF HAZARDOUS AND MIXED
WASTES AT A NUCLEAR POWER GENERATING
STATION: A CASE HISTORY
Freeman C. Cook, Jr., Radiation Consultant
Scientific Ecology Group, Inc.
Oak Ridge, Tennessee 37830
Greg Taylor, Environmental Supervisor
Iowa Electric Light and Power Company
Duane Arnold Energy Center
Palo, Iowa 52324
INTRODUCTION
In 1992, Iowa Electric Light and Power Company developed and implemented a mixed waste
management plan at the Duane Arnold Energy Center (DAEC), a 565 megawatt nuclear power
generating station located in Palo, Iowa. The goal of the DAEC mixed waste program is to ensure that
any mixed hazardous/radioactive waste generated at the DAEC facility will be managed (a) in an
environmentally responsible manner, (b) in accordance with ALARA principles, and (c) in compliance
with applicable environmental control regulations. This paper presents an overview of the DAEC's-
mixed waste management program and other pertinent information on mixed waste issues.
REGULATORY OVERVIEW
Mixed wastes are wastes that contain both a hazardous waste component regulated under Subtitle C
of the Resource Conservation and Recovery Act (RCRA) and a radioactive component consisting of
source, special nuclear, or byproduct material regulated under the Atomic Energy Act (AEA). The
dual regulatory framework for mixed wastes stems from the RCRA definition of solid waste. Hazardous waste is defined as a subset of solid waste. RCRA specifically excludes from the definition of solid
waste "source, special nuclear, or byproduct material as defined by the Atomic Energy Act of 1954, as
amended" [RCRA Section 1004 (27)]. These radioactive materials are regulated by the NRC and
include the following waste classes: transuranic waste, high-level waste, low-level waste, and spent
nuclear fuel. Any class of radioactive waste that contains a hazardous waste as defined under Subtitle
C of RCRA is considered a mixed waste. The radioactive component of the mixed waste generated at
the DAEC is low-level.
The 1984 Hazardous and Solid Waste Amendments (HSWA, 1984) significantly expanded the scope
of RCRA as it relates to hazardous waste. The expanded requirements that are particularly relevant to
mixed waste management include land disposal restrictions (LDR), minimum technology requirements, and corrective action requirements. HSWA requires EPA to evaluate all listed and characteristic hazardous waste to determine which wastes should be restricted from land disposal. LDR wastes
are prohibited from land disposal (landfilling) unless the wastes are treated to meet a specified
concentration level or technology requirement. In addition to prohibiting the land disposal of hazardous waste without proper treatment, LDR requirements (40 CFR Part 268) prohibit the storage of
restricted wastes unless the storage is for the sole purpose of accumulating sufficient quantities of
LDR wastes for recovery, treatment, or disposal.
Since limited commercial treatment or disposal capacity currently exists for mixed LDR wastes,
DAEC is required to store these mixed wastes on-site until disposal arrangements can be made or
additional capacity becomes available. Storage of hazardous or mixed waste for longer than the 90-
day accumulation period allowed under 40 CFR 262.34 requires a RCRA Part B permit or interim
status. At DAEC, a secure area inside the protected area of the plant has been designated as the on-
site container storage area for accumulating mixed wastes. Pursuant to EPA's "Clarification of
Interim Status Qualification Requirements for the Hazardous Components of Radioactive Mixed
48th Purdue Industrial Waste Conference Proceedings, 1993 Lewis Publishers, Chelsea, Michigan 48118. Printed in
U.S.A.
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