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HAZARDOUS WASTE INCINERATION: QUESTIONS AND ANSWERS
Prepared for
Office of Solid Waste
U.S. Environoental Protection Agency
April 5. 1988
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ACKNOWLEDGEMENTS
This booklet was developed by Lori' DeRose and Vanessa Musgraye of the
Office of Solid Waste, U.S. Environmental Protection Agency, and Leslie
Kostrich, Nancy Knapperiberger,|David Helzner, Andy Szatkowski, Richard
Lipinski, and David Jensen of IGF Incorporated, Fairfax, Va. We
particularly would like to acknowledge the special contributions of the
following: Matt Hale, Frank MdAlister, Sonya Stelmack, Robin Anderson,
Robert Holloway, and Mary Cunningham of EPA and Lewis Michaelson, Edwin
Berk, Elizabeth Marcotte, Carljst. Gin, Nora Zirps, Gary Dietrich, and
Pamela Bridgen of IGF. We also wish to thank the following EPA staff
who provided information for the booklet and served as reviewers:
Edward Anna, Carol Bass, Pete Bentley, Olga Carey, Linda Galer, Nancy
Grundahl, Lyndell Harrington, JFudy Kertcher, Debra Martin, Bruce Means,
Henry Onsgard, David Redford, Moira Schoen, Adam Sutkus, Marcia
Williams and Larry Zaragoza. ;
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TABLE OF CONTENTS
INTRODUCTION 1
1. HAZARDOUS WASTE INCINERATION: A TECHNICAL OVERVIEW 3
2. THE REGULATORY PROGRAM FOR HAZARDOUS WASTE INCINERATORS 13
3. PERMITS AND THE PERMITTING PROCESS 16
4. ENFORCEMENT OF PERMIT OPERATING CONDITIONS 28
5. GENERAL STANDARDS FOR FACILITIES OPERATING HAZARDOUS WASTE
INCINERATORS 32
6. POTENTIAL RISKS OF HAZARDOUS WASTE INCINERATION 40
CONTACTS FOR FURTHER INFORMATION 44
REFERENCES 46
GLOSSARY . . .47
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INTRODUCTION
This booklet provides answers to questions that citizens may have about
hazardous waste incineration. Many cities and towns operate incinerators
that burn non-hazardous wastes, such as household garbage. Incinerators are
also used to burn hazardous wastes.* Most hazardous wastes are byproducts
of a broad spectrum of industrial and manufacturing processes; other
hazardous wastes result from other activities, for example, the removal of
contaminated soil from a Superfund site or a chemical spill. When managed
improperly, hazardous wastes can pollute the environment, causing harm to
people, animals, and plants. Incineration detoxifies hazardous wastes by
destroying many of the harmful components of the wastes. Based on the
results of research on incineration, JEPA has concluded that incineration is
the best method currently available for treating certain types of hazardous
wastes.
Why is t»ag*»T-Hnng waste incineration important?
EPA expects that increased use of hazardous waste incineration will help
avoid the environmental problems caused by mismanagement of hazardous waste.
EPA studies and independently prepared reports have concluded that hazardous
waste incineration is safe and is preferable in many cases to the primary
competing technology, disposal of wastes on land. In the Hazardous and
Solid Waste Amendments (HKHA) of 1984, Congress mandated a ban on the land
disposal of untreated hazardous wastes. EPA believes that incineration will
play a major role in providing a treatment alternative to land disposal.
Incineration* s main advantage is that it permanently destroys some of
the toxic qualities of the waste. A report by the Congressional Office of
Technology Assessment (OTA) concluded that hazardous waste incineration is
safer than land disposal. The report stated that "it is preferable to
permanently reduce risks to human health arid the environment by waste
treatments that destroy or permanently reduce the hazardous character of the
material, than to rely on long-term containment in land-based disposal
structures."
Incineration has been used in the U.S. and Europe to treat hazardous
wastes for many years. As of 1987, there were over 200 hazardous waste
incinerators operating in the U.S. Most of these incinerators are used by
companies for their own wastes; the remainder incinerate wastes for payment.
Today, incineration is also playing an important role in the cleanup of many
Superfund sites, where it is used for treating contaminated soils and other
wastes removed from the site. In recent regulations that set treatment
standards for hazardous wastes that are to be disposed on land, EPA has
* Words defined in the glossary at the end of the booklet are marked in bold
at their first appearance.
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identified incineration as the Bestj Demonstrated Available Technology (that
is, the commercially developed technology that provides the most effective
treatment) for certain types of wastes.
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EPA believes that greater quantities of hazardous wastes will be treated
using incinerators in the coming ye;ars. As demand for incineration
increases, EPA expects to receive applications for permits from businesses
wishing to build and operate new incinerators. In addition, Congress, in
the Hazardous and Solid Waste Amendments of 1984 (HSWA), gave EPA a deadline
of November 8, 1989 for final decisions on permit applications for hazardous
waste incinerators that were submitted to EPA by November 8, 1984.
Incineration will therefore be more; in the public eye, and will be the
object of more interest and questions from citizens.
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Bhat information can be found in this booklet?
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The focus of this booklet is hazardous waste incineration and its
regulation under the Resource Conservation and Recovery Act (RCRA). Because
hazardous waste is a legal term, wastes must meet specific criteria to be
regulated as hazardous under RCRA. Certain wastes that have dangerous
properties, for example, radioactive wastes and polychlorinated biphenyls
(ECBs), are not included in the legal definition of hazardous waste.
Management of radioactive wastes is regulated by the Nuclear Regulatory
Commission and the Department of Energy; management of PCBs is regulated by
EPA under the Toxic Substances Control Act (TSCA) .
PCI
EPA's regulatory program for PdB incineration is.based on a similar
framework of standards, permits, and enforcement, although there are some
differences in specific procedures [and requirements. This booklet does not
provide information on this program. For more information on incineration
of PCBs, contact your EPA regional !office (see page' 44).
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This booklet is organized into isix chapters. The first chapter answers
questions about the technical aspecjts of hazardous waste incineration.
Chapter 2 provides a general description of EPA's program for regulating
hazardous waste incinerators and describes the federal performance standards
for hazardous waste incinerators. ;Chapter 3 explains the process of
developing and issuing permits, while Chapter 4 describes how permit
conditions are enforced. Chapter 5 describes general standards that apply
to owners and operators of all hazardous waste treatment, storage, or
disposal facilities. The last chapter, Chapter 6, explains the potential
risks involved in hazardous waste incineration.
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CHAPTER 1
HAZARDOUS WASTE INCINERATION: A TECHNICAL OVERVIEU
This chapter describes technical aspects of hazardous waste
incineration, including the following:
Overview of the incineration process;
Types of wastes suitable for incineration;
Descriptions of several of the more common types
of hazardous waste incinerators;
Descriptions of common types .of air pollution
control devices used on hazardous waste
incinerators;
Maintenance requirements for incineration units;
and
Alternatives to incineration;
The chemical reactions that occur during incineration are extremely
complex. The' intent of this chapter is to describe this complex process in
general terms to provide a basic understanding. The variety of incinerator
designs and air pollution control equipment, however, precludes a complete
and detailed discussion of incineration technology. Only the most commonly
used designs and equipment are discussed.
BASIC PRINCIPLES OF INCINERATION
What is incineration?
Incineration is the burning of substances by controlled flame in an
enclosed area (compartment). This process (1) detoxifies hazardous wastes
by destroying organic compounds contained in the wastes, (2) reduces the
volume of the wastes, and (3) converts wastes to solids by vaporizing water
and other liquids the wastes may contain. Organic compounds (compounds
composed of carbon, hydrogen, and sometimes other elements) burn over a
broad range of temperatures. Wood, oil, and coal, for example, are all
composed of organic compounds that burn at relatively low temperatures.
Some organic compounds, including some found in certain hazardous wastes,
burn less readily and must be subjected to higher temperatures before they
burn. A hotter fire also burns more completely than a cooler one. As a
consequence, hazardous waste incinerators must maintain extremely high
temperatures (typically ranging from 1800°F to 2500°F) to ensure that
virtually all organic compounds in the wastes are destroyed. Although
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incineration does not destroy inorganic compounds (carbonless compounds,
such as salts or metals, and carbon [compounds lacking hydrogen, such as
carbon monoxide and carbon dioxide) ,t it can be used for wastes that contain
them in order to prepare the inorganic materials for easier management and
handling. Incineration is more effective, however, in reducing the
hazardous properties of wastes that 'are mainly composed of organic
compounds. '
How does an incinerator work?
Incineration involves four basic' steps:
Wastes are fed into the incinerator;
Wastes are burned, destroying organic compounds
and yielding residual products in the form of
ash and gases; I
Ash Is collected, cooled, and removed from the
incinerator; and
* Gases are cooled, cleaned, and released to the
atmosphere through the incinerator stack (or
chimney). :
The specific equipment used for each step depends on the incinerator type
and the physical and chemical characteristics of the wastes the incinerator
is designed to burn. In addition, steps may be added at various points to
improve efficiency. For example, in some systems, wastes are preheated or
ignited before they enter the parts jof the incinerator where the highest
temperatures are maintained. The picture (see next page) shows a typical
rotary kiln system, one that could be sused for incineration of a wide
variety of wastes.
How are wastes burned In the incinerator?
During a burn (a period during which the incinerator is in operation),
wastes are fed into the incineratorjin batches or in a continuous stream.
Whether continuous or batch, this flow of wastes is generally referred to as
the waste feed. Feed mechanisms are diverse: liquid wastes are often pumped
into incinerators through a nozzle, a device that breaks up the liquid into
fine droplets that burn more easily. Solid wastes may be fed into the
incinerator in bulk or in containers using a conveyer or a gravity system.
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Wastes are burned in the combustion chamber, a furnace-like area that
contains a burner and which Is designed to withstand and maintain extremely
high temperatures. As the wastes are heated, they are converted from solids
or liquids Into gases. The gases are mixed with air and passed through the
extremely hot flame. As the temperature of the gases rises, the organic
compounds in the gases begin to break down into atoms. These atoms
recombine with the oxygeru from the sir to form stable inorganic compounds,
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TYHCAL INaNERATOR PROCESSES
(ROTARY KILN)
SECONDARY COMBUSTION
CHAMBER
FURTHER COMBUSTION
FAN
STACK
EMISSIONS
WASTE
DISPOSAL I
ASH
QUENCH AIR POLLUTION
rnri*%SSi:* SSfS$9k 5SPSL.ro (MAINTAINS PROPER
COOLS GASES AMOVES ACID GASES ASSURE AND
AND PARTICULATES DRAW RATE)
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such as carbon dioxide and water. Depending on waste composition, other
inorganic compounds (for example,, acid gases such as hydrogen chloride) may
form. This entire process is called! conbustion.
Temperatures in combustion chambers vary, but are generally in the range
of l,800eF to 2,500°F, temperatures ^ell above those required to break down
the more difficult-to-burn organic compounds. Wastes are generally
maintained at these elevated temperatures from less than one second to
several seconds. In many incinerators, combustion occurs in two combustion
chambers. Combustion of more easilyi burned organics is completed in the
first chamber. For compounds that are difficult to burn, combustion is
completed in the secondary conbustion chanber after the compounds have been
converted to gases and partially combusted in the first chamber.
What Is the conposition of residuals from the conbustion process?
Combustion yields two residual products: solids, in the form of ash, and
gases. Combustion gases are composed primarily of carbon dioxide and water,
plus small quantities of carbon monoxide, nitrogen oxides, and other gases
that depend on the composition of the waste burned. Ash is an Inert
Inorganic material made up of carbon, salts, and metals. The exact
composition, like that of the gases,I depends on the waste burned. During
combustion, most ash collects at the bottom of the combustion chamber; some
ash, however, is carried along with phe gases as small particles, or
partlculate natter. Different types! of wastes yield different quantities of
ash. Incineration of liquids generally produces very small quantities of
ash relative to the quantity of waste burned. Incineration of solid wastes
yields greater quantities'of ash: typically, from 10 to 30 percent of the
original waste quantity. Ash is rembved from the bottom of the combustion
chamber and, by regulation, is considered a hazardous waste (as are all
residuals from hazardous waste treatment processes, whether or not the
residuals exhibit the character is tic's of hazardous wastes). If the owner or
operator can prove that the ash is nbt hazardous, however, EPA issues an
exemption called a "delisting."
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How are conbustion gases cooled land cleaned before release?
Following combustion, the combustion gases move through various devices
that cool and cleanse the gases before the gases are released to the
atmosphere through the incinerator sjtack. A fan is typically used to
maintain the flow of gases through t|he system. One common cooling system is
a quench chanber, where gases are cqoled by direct mixing with water. Air
pollution control devices are used to remove both particulate matter and
acid gases from the combustion gases. The exact number and types of devices
used will depend on the incinerator [and the types of waste it burns. For
example, hydrogen chloride is created by combustion of wastes containing
chlorinated organic compounds. RCRA standards limit the amount of hydrogen
chloride that can be released through the emission of combustion gases. If
an incinerator is not used for burning chlorinated organic wastes, it will
not require a special device for hydrogen chloride removal.
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Does incineration destroy all organics in the waste?
A well-designed hazardous waste incinerator that is properly operated
will destroy all but a tiny fraction of the organic compounds contained in
the waste. Such incinerators perform at levels extremely close to complete
combustion (that is, the total destruction of all organic compounds), and
new technology is being developed that will improve upon current levels of
performance. Complete combustion is only a theoretical concept, however,
since the development of a 100 percent efficient incinerator is not
possible.
The three critical factors that'determine the completeness of combustion
in an incinerator are (1) the temperature in the combustion chamber; (2) the
length of time wastes are maintained at high temperatures; and (3) the
turbulence. or degree of mixing, of the wastes and the air (an important
determinant of the availability of oxygen during burning). To ensure that
these factors are working together to promote virtually complete combustion,
a RCRA permit for a hazardous waste incinerator specifies allowable ranges
for and requires continuous monitoring of certain critical parameters.
Among these parameters, or operating conditions, are maximum allowable
carbon monoxide levels in emissions, allowable ranges for temperature, and
maximum waste feed rates.
What: is contained in the gases emitted from the incinerator?
Incinerator emission gases are composed primarily of two harmless
inorganic compounds, carbon dioxide and water. The type and quantity of
other compounds depends on the composition of the wastes, the completeness
of the combustion process, and the air pollution control equipment with
which the incinerator is equipped. These compounds include organic and
inorganic compounds contained in the original waste and organic and
inorganic compounds created during combustion:
Organic compounds from the original waste. A
well designed incinerator, when operated
properly, is highly efficient, and will burn all
but a very small quantity of the organics in the
waste. The organics that do not combust are
carried along in the gases leaving the
combustion chamber. As the gaseous, uncombusted
organics move through the remainder of the
incinerator, some are removed by air pollution
control equipment. RCRA standards set a limit
on emissions of designated organic compounds.
Inorganic compounds from the original waste.
Inorganic compounds, such as salts and metals,
do not combust. These compounds end up either
in the bottom of the combustion chamber in the
ash or carried alpng with the combustion gases,
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depending primarily upon their weight. These
inorganic compounds generally are contained in
or adhere to particulate matter. RCRA standards
limit the quantity of particulate matter that
may be emitted from'the incinerator. Air
pollution control devices are therefore used to
remove most particulate matter and adhering
materials from the combustion gases.
Organic compounds not present in the original
waste. Because combustion in an incinerator is
not 100 percent efficient, very small quantities
of "new" organic compounds may form from the
breakdown and recombination of the original
compounds. These compounds are called "products
of incomplete combustion" (or PICs) and are
formed during the combustion of any organic
material. For example, PICs are formed when
wood is burned in wood stoves, or when gasoline
is burned in an automobile engine. The
combustion process may create small quantities
of many different types of PICs and some
fraction of these compounds may be hazardous.
Among the types of compounds found in various
analyses of PICs are Some that are considered
toxic, including dioxins and dibenzofurans. In
a state-of-the-art incinerator, PIC formation is
minimized by keeping the initial products of
combustion at high temperatures for an
appropriate length of time. PICs are destroyed
by the high temperatures maintained in the
combustion zone or a secondary combustion
chamber. Air pollution-control devices also
remove PICs. [
Inorganic compounds not present in the original
waste. In addition to carbon dioxide and water,
combustion always produces small quantities of
carbon monoxide and nitrogen oxides (from the
combination of oxygen: and nitrogen in the air).
Combustion of complex! organic compounds
(including many hazardous wastes) may create
other inorganic compounds' depending on what is
being burned. Many hazardous wastes contain
chlorinated organic compounds, sulfur, or
organically-bound nitrogen. Combustion of these
compounds yields hydrogen chloride, oxides of
sulphur, and oxides of nitrogen, respectively.
Carbon monoxide, as well as nitrogen and sulfur
oxides, are typically, found in auto emissions
and emissions from other combustion facilities,
such as- coal-burning, power plants. Because it
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is more uniquely associated with the burning of
hazardous wastes, RCRA standards place
limitations on emissions of hydrogen chloride.
What types of wastes are incinerated?
Incinerators can be designed to accept wastes of any physical form,
including gases, liquids, solids, sludges (thick, heavy mixtures of liquids and
solids), and slurries (thin mixtures of liquids and solids). Although any waste
can be incinerated, incineration is primarily for the treatment of wastes that
contain organic compounds. Wastes with a wide range of chemical and physical
characteristics are suitable for incineration. Most of these wastes are
byproducts of industrial manufacturing and chemical production processes or
result from the clean-up of contaminated sites.
INCINERATION TECHNOLOGY
Are there different types of hazardous waste incinerators?
The two most common types of hazardous waste incinerators are rotary kiln
and liquid injection. Other types exist, some of which are becoming more widely
used; others are still in the developmental stage. Choice of a particular type
of incinerator design is determined primarily by the types of wastes to be
treated.
Rotary kiln incinerators are versatile units that can accept gases, liquids,
sludges, slurries, and solids either separately or simultaneously, either in
bulk or in containers. Because of this versatility, rotary kilns are commonly
used to treat a variety of wastes. The kiln is a cylindrical shell mounted on
its side at a slight angle to the horizontal. As the kiln rotates and the
wastes travel down the slope, the organic chemicals in the waste convert into
gases and partially combust. The gases then pass into another combustion
chamber (called an afterburner or the secondary combustion chamber) where more
complete combustion is achieved. Ash residue is removed from the lower end of
the kiln.
Liquid injection incinerators are capable of accepting gases, liquids, and
slurries. The heart of the liquid injection incinerator is a nozzle or some
other device that "atomizes" the liquid stream. Pumped at high pressure through
the atomizer, the liquids emerge as tiny droplets that mix well with air and
auxiliary fuel and easily convert into gases. Liquid injection systems are
often designed for specific wastes. Consequently, the design of the atomizing
device limits the types of wastes that a particular incinerator can treat. In
spite of this disadvantage, liquid injection systems are widely used where
versatility is not a primary requirement, or as an adjunct to a more flexible
unit, such as the rotary kiln.
Mobile incineration systems have been constructed using various designs.
These systems are hauled to a site on flat-bed trucks, then assembled and
tested. Mobile incinerators are usually smaller than stationary facilities, but
they operate on identical principles. Incinerators may also be mounted on ships.
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Among the many types of hazardous waste incinerators, one of the more common
types is the fluidized bed. Fluidized bed incinerators burn finely divided
solids, sludges, slurries, and liquids. The bed consists of an inert granular
material, usually sand, that is suspended by pressurized air in a highly
turbulent, or fluidized state above the combustion chamber floor. Waste is
conveyed into the fluidized bed where direct contact with the bed material
improves the transfer of heat. Combustion gases move out of the combustion
chamber for cooling and further treatment. Ash caught in the bed material is
eventually removed when the bed material is replaced.
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What: types of pollution control [devices are used on hazardous waste
incinerators?
Combustion gases are typically treated to remove inorganic acid gases and
particulate matter. Particulate matter (and adhering metals) can be removed
with several devices. One of the oldest methods is baghouse filtration which
involves passing the gas through a material (usually fabric) that collects the
particulate matter. Another method Involves electrostatic precipitators; the
particulate matter is electrically charged and collects on plates that are
oppositely charged. The particulate matter is then periodically cleaned from
the plates. Still another approach iis the venturi scrubber. Venturi scrubbers
use high-pressure water to remove the particulate matter.
Hydrogen chloride gas is typically removed using other types of scrubber
devices. Some examples are packed bed, spray tower, and plate tower scrubbers.
These scrubbers bring alkaline waterj and the combustion gases together,
providing the greatest possible contact between the water and the gases. The
water is broken up into fine droplets and sprayed into the gas or the gas is
broken up into small bubbles and flows up through the water. This allows
hydrogen chloride, an acid gas, to dissolve in and be neutralized by the
alkaline water. Also available are ;dry scrubbers which use either dry scrubbing
material or an alkaline slurry which is dried when it is injected in to the,hot
combustion gases. Venturi scrubbers are not generally used for hydrogen
chloride removal; however, the use of alkaline water in a venturi scrubber will
remove some hydrogen chloride, in addition to removing particulate matter.
Many air pollution control devices use water, thus creating wastewaters
containing the pollutants that have been removed from the gases. The Clean
Water Act sets requirements for wastewater discharges, placing limits on
temperature, pH (a measure of acidity or alkalinity), quantity of suspended
solids, and pollutant levels. Any wastewaters from the incinerator not meeting
these requirements must be treated before being disposed or released to a river,
stream, or sewer system. Possible treatments include settling, metals
precipitation, and neutralization, i
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What maintenance does an incinerator require?
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Equipment maintenance varies greatly depending upon the type of equipment,
its materials of construction, and the chemical and physical stresses to which
the equipment is subjected. For example, the heat-resistant lining in the
combustion- chamber normally lasts two to three year** but incineration of wastes
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containing alkali metals may require the lining to be replaced every four
months. To ensure that the incinerator functions properly throughout its
lifetime, RGRA permits require that the owner or operator of the facility
perform regular inspections and maintenance according to schedules included in
the permit (Chapter 5 provides more information on these requirements). In
addition, the regulations require that an incinerator maintain the same
operating conditions (such as temperature) that it did when it was tested. The
incinerator must be maintained properly in order to achieve the operating
conditions. EPA (or the responsible state agency) also conducts periodic
inspections and may review maintenance records and other data to ensure that the
incinerator continues to operate well. Furthermore, the permit is effective for
no more than ten years, less than the potential life of the incinerator. Thus,
the performance and operating condition of older incinerators are scrutinized
when permits come up for renewal.
ALTERNATIVES TO INCINERATION
How does incineration conpare to land disposal?
Incineration, since it is a method of treatment rather than disposal, has
several advantages over land disposal methods. Incineration breaks down organic
compounds, permanently eliminating environmental hazards'posed by them. Land
disposal only controls the hazard as long as the wastes remain contained in the
disposal unit. The very small amounts of hazardous compounds released during
incineration are released in a slow, controlled manner so that they do not pose
any threat to nearby residents or the surrounding environment. Although
incinerator ash requires disposal in a landfill, the process of incineration
greatly reduces the volume of the material to be disposed. This is extremely
valuable, given that space in landfills is becoming increasingly scarce. In
addition, ash consists mostly of inert material, whereas organic compounds may
react with other compounds in the landfill to form acids that hasten
deterioration of liners that contain the wastes in the landfill.
Today, the principal disadvantage of incineration compared to land disposal
is that of cost. However, as the land disposal restrictions instituted by HSWA
begin to go into effect, the land disposal alternative will become more costly
since producers of hazardous wastes will have to treat wastes before they can be
disposed on land. Land disposal costs will also increase over the coming years
because of changes in RCRA requirements. Thus, the cost difference between
incineration and land disposal will disappear for some wastes and become less
important for others. For many types of hazardous wastes, incineration will
become the least expensive treatment alternative.
Rather than building incinerators to treat their hazardous waste, why don't
companies change their production processes so that these wastes are not
produced? ,
Waste minimization, that is, steps that eliminate or reduce the production
of hazardous wastes, is becoming increasingly important as society deals with
the problem of hazardous waste. EPA encourages waste minimization, and is
assisting companies in determining how waste minimization techniques can be
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applied to their processes. The move towards waste minimization is a gradual
process, however, and it is likely po take many years before hazardous waste
volumes are significantly reduced. ; In addition, waste minimization techniques
will not totally eliminate the need for treatment and disposal technologies.
Incineration should therefore remain an important technology for treating
hazardous wastes, even as less wastje is produced.
Are there any other alternatives to incineration?
Many new types of thernal treatment: technologies are currently being
studied. Incineration is one type of thermal treatment that uses combustion
(burning) in the presence of oxygen; to destroy hazardous compounds. Other
thermal treatments use hot fluids or other materials with elevated temperatures
to treat wastes. At this time, most of these technologies are probably too new
to be considered commercially available alternatives to incineration, but they
may play an increasingly significant role in the future. These new technologies
include pyrolysis, ntolten salt reactors, reaction in supercritical water, and
plasaa-arc reactors. Of these technologies, only pyrolysis is commercially
available now. The others are in the developmental stages.
For some types of liquid organic wastes, biological or chemical treatment is
an economical and effective alternative to incineration. Biological treatment
breaks down organic wastes using microorganisms that consume the organics.
Although these systems cannot presently tolerate very toxic wastes or wastes
containing more than small amounts jsf inorganics, future biotreatment systems
may be developed which can treat a greater variety of wastes. Several forms of
chemical treatment can be used to rpcover valuable materials in the wastes, such
as solvents. Some processes that allow solvent recovery are distillation, steam
stripping, and solvent extraction. I These processes may be preferable to
incineration if the chemicals contained in the waste are expensive to produce or
if the waste is only slightly contaminated. Other forms of chemical treatment
(for example, lime precipitation) are more effective than incineration for
wastes containing large quantities of- metals or wastes composed mostly of
inorganic chemicals. ',
Based on current data, EPA believes that incineration is the best technology
available for the treatment of many organic wastes. Although there are still
some areas of technical and scientific uncertainty concerning incinerator
emissions, incineration is preferabjle to alternative technologies such as land
disposal because it reduces both waste toxicity and volume.
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CHAPTER. 2
THE REGULATORY PROGRAM FOR HAZARDOUS WASTE INCINERATORS
The treatment, storage, and disposal of hazardous wastes, including land-
based incineration of hazardous wastes, is regulated under Subtitle G of The
Resource Conservation and Recovery Act (RCRA). RCRA was passed by Congress in
1976 and amended by the Hazardous and Solid Waste Amendments (HSWA) in 1984.
Under RCRA, EPA is required to set standards for the management of hazardous
waste from "cradle to grave," from the time t e waste is first, produced until it
is treated or disposed. RCRA provides EPA with the authority to develop
standards for producers and transporters of hazardous wastes and facilities that
treat, store, or dispose of hazardous waste. RCRA requires that these standards
be sufficiently stringent to protect human health and the environment.
Who regulates hazardous waste incinerators?
RCRA gives states the option of developing and administering their own
hazardous waste programs in place of the federal program that EPA administers.
EPA must approve a state's program before it can take the place of EPA's
program. To gain approval, a state program must be consistent with and
equivalent to the federal RCRA program, and at least as stringent. State
programs may be more stringent or extensive than the federal program. For
example, a state may adopt a broader definition of hazardous waste in its
regulations, designating certain wastes hazardous that are not hazardous under
the federal regulations. This booklet describes the federal RCRA program, the
minimum requirements applicable throughout the country. These regulations are
contained in Parts 260-271 of Volume 40 of the Code of Federal Regulations.
Volume 40, Part 264 of the Code of Federal Regulations contains standards for
permitted hazardous waste facilities; Subpart 0 of Part 264 gives the specific
standards for incinerators. Regulations that are new or have not been finalized
can be found in the Federal Register, a document that is published daily and
contains notification of government agency actions,.
How do regulations ensure safe operation of nazardous waste Incinerators?
EPA has developed performance standards for the Incineration of hazardous
wastes based on research on incinerator air emissions, and health and
environmental risk studies. These standards have been developed under RCRA to
ensure that incineration is carried out in a safe manner and poses no threat to
the health of people living or working nearby or to the surrounding environment.
All incinerators emit gases through a stack, or chimney, as the final step in
the incineration process. These gases are composed primarily of carbon dioxide
and water vapor, two harmless gases, but may contain trace quantities of
pollutants, as do emissions from other fuel-burning facilities, such as power
plants. The quantity of pollutants in the emissions is the major determinant of
the risk of incineration. The performance standards cover emissions of
designated organic compounds, hydrogen chloride, and particulate matter.
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In addition to performance standards, owners or operators-of incinerators
are subject to general standards that apply to all facilities that treat, store,
or dispose of hazardous waste. General standards cover such aspects of facility
operations as personnel training, inspection of equipment, and contingency
planning. These standards are discussed in more detail in Chapter 5.
How can EPA or the state ensure that incineration facilities will operate
according to regulations? >
Facilities that incinerate hazardous wastes, like other facilities that
treat, store, or dispose of hazardous wastes, must apply for and receive a RCRA
permit. This permit, based on a detailed analysis of the data provided by the
permit applicant (either the owner or operator of the incinerator), specifies
conditions for operations that ensure that the incinerator will meet all
applicable RCRA standards> Permits jean be issued by EPA or by states with
approved RCRA programs. The procedures followed for issuing or denying a
permit, including provisions for public comment and participation, are similar
whether EPA or a state agency is responsible. (Chapter 3 discusses the
permitting process.) j
i
Once a permit is issued, the owner or operator of the incinerator is legally-
bound to operate according to the conditions specified within it. The
permitting agency enforces the permit by periodically inspecting the facility to
ensure that it is meeting the conditions specified in its permit. When owners
or operators fail to meet the requirements of their permits, they are subject to
a broad range of civil and criminal factions, including suspension or revocation
of their permit, fines, or imprisonment., (A more detailed discussion of
enforcement is found in. Chapter 4.)
[
How does EPA. Measure incinerator performance?
i
"to qualify for permitting, an incinerator must be able to burn wastes and
cleanse combustion gases so that only very small quantities of pollutants are
emitted through its stack. EPA's principal measure of incinerator performance
is destruction and reaoval efficiency (DUE). Destruction refers to the
combustion of the waste, while removal refers to the cleansing of pollutants
from the combustion gases before they are released from the stack. For example,
a 99.99 percent ORE (commonly called "four nines DRE") means that one molecule
of an organic compound is released to the air for every 10,000 molecules
entering the incinerator; a DRE of 99.9999 percent ("six nines") reduces this to
one molecule released out of every \,000,000 molecules.
Do perfomance standards apply to all pollutants present ±in the original
waste?
It is technically infeasible to monitor DRE results for all organic
compounds contained in the waste feed. Therefore, selected hazardous compounds,
called the principal organic hazardous constituents (POHCs), are designated in
the permit. POHCs are selected based on their high concentration in the waste
feed and their difficulty to burn compared to other organic compounds in the
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waste feed. If the incinerator achieves the required DRE for POHCs, then the
incinerator should achieve the same or better DRE for organic compounds that are
easier to incinerate.
What: levels of incinerator perfomance do RGRA standards require?
RCRA performance standards require: (1) a minimum destruction and removal
efficiency of 99.99 percent for organic compounds designated in the permit as
the principal organic hazardous constituents, or POHCs; (2) a minimum
destruction and removal efficiency of 99.9999 percent for dioxins and
dibenzofurans; (3) removal of 99 percent of hydrogen chloride gas from the
incinerator emissions, unless the ^quantity of hydrogen chloride emitted is less
than 4 pounds per hour; and (4) a limit of 180 milligrams of particulate matter
per dry standard cubic meter of gas emitted through the stack. These standards
were set based on analyses of potential risks to health or the environment and
the levels of performance that have been measured for properly-operated,
well-designed incinerators. Although the 99.99 DRE is protective of human
health and the environment, a more stringent standard of 99.9999 DRE was set for
wastes containing dioxins or dibenzofurans because of EPA's and the public's
concern about these particularly toxic chemicals.
Do perfomance standards differ for incinerators ithich accept FCBs?
TSCA standards are somewhat different in form from RCRA standards. For
incineration of liquid PCBs, TSCA standards set a minimum "dwell" time (time in
the combustion chamber), temperature, and oxygen levels. For non-liquid PCBs,
the TSCA standards require 99.9999 DRE. Although the general TSCA standard for
liquid PCBs should result in 99.9999 DRE, EPA requires permit applicants wishing
to burn liquid PCBs to make a demonstration to prove that they will achieve
99.9999 ERE during incineration.
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[CHAPTER 3
PERMITS AND THE PERMITTING PROCESS
Permits are developed by determining the conditions under which a facility
may operate, while meeting all applicable standards. These operating conditions
are specified in the permit as the -only conditions under which the facility may
legally operate. The permit also specifies the maximum rate at which different
types of wastes may be incinerated,! maintenance and inspection procedures,
training requirements, and other conditions that affect the operation of the
incinerator. The permit similarly 'sets conditions for all other hazardous waste
storage, treatment, or disposal units to be operated at the facility.
This chapter provides an overview of EPA's permitting process.
covered include: '
The purpose of the penrjit;
I
How the permitting process works;
i
How the public can participate in the-
permitting. process; ;
How location-related factors are considered in
the permitting process;' and
i
Information an trial burn procedures.
The topics
PERMITS AND THE PERMITTING PROCESS
Hov does the permit ensure that .privately owned or operated hazardous waste
incinerators operate according
to standards?
To ensure that the performance standards are met, the permit for'an
incinerator specifies operating conditions that have been proven to result or
are expected to result in the incinerator meeting the performance standards.
The permit may specify different operating conditions for different types of
waste feeds. These operating conditions specify ranges or minimum or maximum
levels for different parameters, such as 'temperature. The permitting agency has
discretion to set operating conditions for any parameter the permitting agency
considers necessary to ensure that the incinerator meets performance standards.
i
Can a hazardous; waste incinerator operate without a permit;?
Recognizing that it would take EPA and authorized states many years to
process all permit applications, Congress allowed hazardous waste facilities
that were under construction or in (Operation by November 19, 1980 to operate
without a permit, providing that the facilities qualified for interim status.
To obtain interim status, owners or, operators of hazardous waste facilities were
required to submit the first part, Part A, of a two-part permit application.
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Part A of the permit application is a standard form, while Part B is a more
extensive description of the facility, including detailed and highly technical
information. It may take several years to prepare Part B of a permit
application and several more for the permitting agency to complete its review
and provide for opportunity for public comment. Although interim status
facilities are subject to general and specific standards, these standards are
less strict than those that apply to permitted facilities.
In the Hazardous and Solid Waste Amendments of 1984 (HSWA), Congress
established a deadline of November 8, 1986 for submission of Part B of the
permit application for interim status incinerator -. Owners and operators of
interim status incinerators that failed to meet t. is deadline will lose interim
status on November 8, 1989, requiring that they close their incinerator. In
HSWA, Congress also established deadlines for EPA for processing permit
approvals or denials. Permit applications for incinerators received by EPA
before November 8, 1984 must be approved or denied by November 8, 1989. There
are currently no time limits for applications received after that date.
How are interim status incinerators permitted?
Because Congress allows interim status incinerators to operate without a
permit, EPA has developed different approaches to permitting interim status and
"new" incinerators (those for which construction began after November 19, 1980).
Owners and operators of interim status incinerators must demonstrate that their
incinerator meets all applicable performance standards by submitting performance
data developed during actual burns. Performance data are used to determine
whether the incinerator meets RCRA performance standards when burning a specific
waste under a specific set of operating conditions. Many applicants develop
such data for a number of different wastes and for a variety of operating
conditions to support their applications. These data are developed during a
trial burn, a test during which sufficient data are gathered to assess the
incinerator's ability to meet performance standards. Although the owner or
operator of an interim status incinerator does not require prior approval to
conduct a trial burn, it is within the permitting agency's discretion to reject
the trial burn data, if insufficient to evaluate incinerator performance.
Therefore, many owners or operators of interim status incinerators seek prior
approval of a trial burn plan, a detailed description of how the trial burn is
to be carried out.
How are new incinerators permitted?
Anyone wishing to operate a new hazardous waste incinerator is required to
obtain a RCRA permit before construction of the unit begins. The RCRA permit
for a new incinerator covers four phases of operation: (1) a "shake-down"
period, during which the newly-constructed incinerator is brought to the level
of normal operating conditions in preparation for the trial burn; (2) the trial
burn period, during which burns are conducted so that performance can be tested
over a range of conditions; (3) the period following the trial burn (this period
may last several months), during which time the data from the trial burn is
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evaluated and the facility may operate under conditions specified by the
permitting agency; and (4) the final operating period, which continues
throughout the life of the permit (10 years or less).
The permitting agency specifies I operating conditions for all four phases
based on a technical evaluation of the incinerator design, the information
contained in the permit application and trial burn plan, and results of trial
burns for other incinerators. These operating conditions are set so that the
incinerator theoretically will meet;all performance standards at all times.
Results from the trial burn are usecl to verify the adequacy of these conditions.
If the trial burn results fail to verify that performance standards can be met
under some operating conditions, the permit will be modified for the final
operating phase so that the incinerator cannot operate under these conditions.
i
What information does the permitting agency require to determine whether an
applicant should be given a pernit to operate a. hazardous waste incinerator?
i
All RCRA permit applicants must submit a complete permit application.
Permit applicants for hazardous waste incinerators must also submit performance
data that demonstrate the conditions under which the incinerator can meet the
minimum performance standards, or, in the case of a new incinerator, a trial
burn plan detailing how these data Will be developed during the incinerator's
trial burn. |
RCRA standards specify the information that must be provided in the permit
application and give the permitting agency broad authority to request any
additional information it requires to identify the necessary operating
conditions for the facility permit. | The RCRA permit application consists of two
parts, Part A and Part B. Part A provides general information including the
name and location of the facility; its owner; its physical layout; and the types
and quantities of wastes that will be managed at the facility. Part B, which
has no standard format, contains detailed technical information on the
facility's equipment, operating procedures, training and inspection programs,
emergency prevention and response procedures, environmental monitoring systems,
and geological and other physical characteristics. It is not unusual for a Part
B application to be several volumes in length.
!
|
How is a. permit application reviewed?
The process by which a permit application is reviewed may vary somewhat
depending on the permitting agency. | The basic process, however, consists of
five steps:
(1) EPA or the authorized state reviews the application for
completeness. If information is missing, the reviewer
issues a Notice of Deficiency to request additional
information from the applicant.
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(2) The permitting agency evaluates the application and any
other information submitted by the applicant (for example,
performance data from an interim status incinerator or a
trial burn plan for a new incinerator).
(3) The permitting agency prepares either a draft permit: if it
judges that the facility meets the regulatory standards,
or it issues a notice of intent to deny the application.
In either case, a notice is sent to the applicant and is
published in a local newspaper. Issuance of a draft
permit does not constitute final approval of the permit
application. The draft permit, however, consists of all
the same elements as a final permit, including technical
requirements, general operating conditions, and special
conditions developed specifically for the individual
facility, including the duration of the permit.
(4) The permitting agency solicits and receives comments from
the public during a formal public content period. If
requested to do so, the permitting agency will give notice
of and hold a public hearing during the public comment
period.
(5) After considering the technical merits of the comments,
the permitting agency makes a final decision on the
application. The permit is either issued or denied. If a
permit is issued, the permit conditions are based on a
careful examination of the complete administrative record,
including all information and data submitted by the
applicant and any information received from the public.
The permit, as issued, may differ from the draft permit.
It may correct mistakes (for example, typographical
errors) or it may contain substantive changes based on
technical or other pertinent information received during
the public comment period. If the permitting agency
intends to make substantive changes in the permit as a
result of comments received during the public comment
period, an additional public comment period may be held
before the permit is issued.
Who decides whether or not the permit should be issued or denied?
The person with primary responsibility for evaluating the application and
for writing or denying the permit is called the permit writer. Although he or
she may be assisted by other staff in reviewing parts of the application, the
permit writer will be involved in every aspect of reviewing the application,
developing a proposal for responding to the application, receiving and
responding to comments from the public on the proposal, and modifying the
proposal, as necessary. The permit writer, by virtue of his or her technical
expertise, familiarity with the facility, and involvement in every stage of the
permitting process, is the key staff member responsible for determining the
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operating conditions under which theifacility will be able to meet applicable
RCRA standards, and for making sure the permit only allows operations consistent
with those conditions. The permit writer, although playing a major role in the
decision process, does not make the final decision on whether to grant or deny a
permit. The responsibility for that:decision rests with the head of the
permitting agency or with another senior agency official to whom the
responsibility has been delegated.
Does EPA complete an Environmental Impact Statement before issuing a RCRA
permit? |
In 1979, EPA determined that preparation of an Environmental Impact
Statement (EIS) is not required in connection with the issuance of RCRA permits.
Environmental Impact Statements are required by the National Environmental
Policy Act when actions of federal agencies may adversely affect the
environment. Since the procedures for issuing RCRA permits result; in a rigorous
review of environmental and health considerations, the health and safety of the
community and the environment can be;ensured without an EIS.
What is to prevent a facility, once it has a permit, from expanding its
operations?
The permit specifies limits on all aspects of operations. For example, the
permit limits the maximum amount, as well as the type of wastes that can be
incinerated; and specifies whether tljie facility can incinerate only its own
wastes or can accept wastes from other generators. If the facility wishes to
deviate from any conditions specified in the permit, it must apply for a permit
modification. Any request to expand operations would require a major
modification of the permit. For major modifications, the permitting agency must
follow public notice, comment, and hearing procedures similar to those required
for the original permit. '
What happens if an incinerator deviates from the operating conditions
specified in the permit? ;
i
During operations, the permit requires continuous monitoring of certain
parameters (for example, combustion temperature) to ensure that they are within
the ranges specified by the permit. If parameters deviate from these ranges, a
sensor will trigger the automatic waste feed shut-off system which is required
in all permitted incinerators. This:system promptly cuts off the feeding of
wastes to the incinerator. The waste feed will not resume until the required
operating conditions have been restored.
Hov does an automatic waste feed;shut-off system work?
The mechanisms that stop the waste feed differ, depending on the design of
the incinerator. In one common type I of system, sensors, which operate
continuously, are connected to the feed valve through electrical relays. When
certain operating parameters deviate from ranges set by the permit, sensors
automatically trigger the closing of;the feed valve. The automatic shut-off
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system must be tested weekly unless the owner or operator can demonstrate that
the weekly inspections unduly disrupt operations and that less frequent
inspections will not affect safety. In some systems, these sensors are also
connected, on separate circuits, to a back-up alarm system. Back-up alarms
might consist of audio-visual displays that can alert plant operators to
potential problems (if the system approaches permit or other operating limits,
but is still within limits) as well as any change in parameters that would
trigger the automatic s'.vat-off system. Then, if the automatic shut-off fails,
the plant operator can cut off the waste feed using manual controls.
PUBLIC INVOLVEMENT IN THE PERMITTING PROCESS
How can local residents make sure that the permitting agency considers their
concerns before granting the facility a permit?
Before a permit is issued, members of the public, have opportunities to
express their views during the public comment period. Prior to this comment
period, EPA or the state agency makes a tentative decision concerning whether to
issue or deny the permit. The agency-issues a public notice of its decision,
allowing a minimum of 45 days for written comments. In the special case of
permits for the incineration of wastes containing dioxins or dibenzofurans, the
comment period is extended to a minimum of 60 days. Along with the public
notice, the agency must prepare a fact sheet to inform citizens about'the
permitting process and the basis of the agency's tentative decision. Both the
fact sheet and the draft permit are made available for public review.
Members of the public may submit written comments (including questions) to
the agency during the public comment period. All comments become a part of the
administrative record, which forms the basis for any subsequent action on the
draft permit. Issues raised during the public comment period often cause the
permitting agency to rethink certain aspects of the draft permit. The draft
permit may be changed or revised because of new technical information or to
address concerns about the technical operations of the facility.
Are written comments the only way citizens can participate in the permitting
process?
Aside from submitting written comments, there are other means by which
citizens can participate in the permitting process. EPA or the state must hold
a formal public hearing on the draft permit, if someone requests one in writing
during the public comment period. The hearing provides ah additional
opportunity for members of the public to express their views and concerns. The
proceedings and any written statements received at the hearing become part of
the administrative record. If a hearing is held, the public comment period is
automatically extended to the close of the hearing, and may be extended beyond
the close of the hearing by the hearing officer. If interest warrants; the
agency may also hold informal meetings with people from within the community to
hear their views and respond' to questions.
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After the close of the public comment period, the permitting agency
carefully considers the entire administrative record for the permit application,
including all written comments and any comments made during the public hearing.
Comments made at informal meetings are not part of the administrative record and
therefore cannot be formally considered by the permitting agency as it makes its
final evaluation of the permit application. After this evaluation, the permit
is written and the decision on the permit is issued, along with the Response to
Coonents, a. document that summarizes and responds to all significant comments
received during the comment period. This document specifies which provisions,
if any, of the draft permit have been changed in the permit and the reasons for
the change. Under certain circumstances, the conditions included in the permit
may be appealed.
Before ^
any decisions, will EPA or the state consider the likely
inpact: of the incinerator on the surrounding connunity?
RCRA requires that facilities operate in a manner that protects human health
and the environment. To that end, federal standards for hazardous waste
facilities are designed to ensure that the health of individuals in the
community is protected and that the facility will not cause environmental
damage. When evaluating a permic application, the permitting agency considers
only those factors affecting compliance with these standards. It is not within
the scope of the standards to consider the potential effects of the facility on
other aspects of community life.
What if residents are opposed to the location and operation of an
incinerator in their co^Kunity?j
During the public comment period, all members of the community are afforded
an opportunity to express their concerns about the operating conditions proposed
by the permitting agency in the drajft permit or about any aspect of the data
submitted by the permit applicant as part or in support of the application. The
permitting agency will take into account any technical information relating to
the ability of the incinerator to meet performance standards under the proposed
permit conditions . Permitting agenfcies , however , do not have authority to
reject permit applications on non- technical grounds. If the permit applicant
demonstrates that the facility meets all RCRA standards and does not pose a
threat to human health or the environment, the permitting agency must issue the
applicant a permit.
Will the operation of the incinerator produce unpleasant smoke, odors, or
noise that: disturbs people living and working nearby?
t - . . -..--. ..--.'
A well-operated incinerator is smokeless and odorless. A white cloud,
similar to what can be seen from a, power plant, may be visible at times. Ihese
emissions are primarily water vapor. Other activities at the site, for example,
storage or waste transfer, may occasionally produce odors., RCRA requires that
all containers containing hazardous waste be sealed, minimizing odors from, wastes
stored in containers. Although operation of the incinerator should not
contribute to area noise levels, there may be noise from additional truck
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traffic to and from the facility. EPA does not have authority under RCRA to
directly regulate noise or odors from an incinerator. In some cases, local
regulations may empower local authorities to address these problems.
LOCATION AND PERMITTING
Are there any prohibitions or restrictions on the location of hazardous
waste incinerators?
RCRA currently includes special requirements for incinerators and other
facilities located in 100-year floodplains (areas with a 1 percent or greater
chance of flooding in any given year) and bans the location of new facilities in
certain areas of seismic activity./ Location of hazardous waste management
facilities on certain types of lands may be prohibited by the requirements of
federal regulations issued under statutes other than RCRA. Lands protected by
these federal statutes include archaeological and historical sites, critical
habitats for endangered or threatened species, wetlands, wilderness areas,
parks, wildlife refuges, coastal areas, and scenic rivers, -among others. The
location of an incinerator facility in such areas must be consistent with the
requirements of the relevant statutes and standards or the permit application
will be denied.
In addition, HSWA authorizes EPA to develpp location standards for hazardous
waste treatment, storage, and disposal facilities, including incinerators. EPA
is currently in the process of doing so, and expects these standards to be made
final in 1989.
Why is a particular location chosen for an incinerator when there may be
more suitable sites?
Criteria for site selection depends on the needs the incinerator is intended
to meet. Generally, a commercial waste management company is likely to consider
proximity to potential customers, the cost of the land, the cost of labor, and
local zoning or land use ordinances when selecting a location.
Zoning and land use are local issues. EPA develops RCRA standards so that
health and the environment will be protected no matter where the incinerator is
located. EPA and authorized state agencies give careful consideration to the
physical suitability of the site before granting a permit. They cannot,
however, deny a permit because there may be a better site elsewhere. As part of
the permit application, the owner or operator must submit information on the
site's location and data pertaining to its physical characteristics, including a
topographical map, aspects of the site's hydrogeology, and prevailing wind
patterns. The permitting agency considers this information in developing permit
conditions to ensure that operations will meet all applicable RCRA standards.
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TRIAL BURN PROCEDURES
What is a trial burn? ,
i .',:,.
A trial burn is a test of an "incinerator's ability to meet all applicable
performance standards when burning a waste under a specific set of operating
conditions. Before final permits for hazardous waste incinerators can be
issued, owners or operators must demonstrate that their incinerator meets
performance standards. Data to be used in evaluating an incinerator's
performance are generally gathered by conducting a trial burn.
Vhat lhappens chi-ring the trial burn?
I
Because data from the trial burn are the main basis for proving that the
operating conditions included in the RCRA permit will result in the incinerator
meeting performance standards, the !trial burn is designed to provide data that
demonstrates the incinerator's capabilities. Many companies hire outside
contractors to conduct trial burns.| During the trial burn, the owner or
operator measures the waste feed rate, levels of carbon monoxide in the stack
emissions, combustion temperature, combustion gas velocity, and other
parameters. In order to "make judgments concerning the incinerator's destruction
and removal efficiency (DRE), the owner or operator must also measure the
quantities of designated constituents, the principal organic hazardous
constituents (POHCs), emitted from phe incinerator. The permitting agency
selects one or more POHCs for each waste feed tested. Emissions of particulate
matter and hydrogen chloride are al$o measured during the trial burn, as is the
efficiency of hydrogen chloride remioval systems if hydrogen chloride emissions
exceed 4 pounds per hour. |
The waste feed burned in the trial burn may take one of three forms:
Actual wastes or mixtures of wastes normally expected to
be burned at the incinerator;
Actual wastes with increased levels of hazardous chemicals
or additional hazardous chemicals added; or
i
Artificial wastes selected by the applicant that provide
suitable proxies for the actual wastes.
I
In order to establish the most flexible permit conditions, the trial burn
may involve incineration of different waste feeds using a wide range of
operating conditions. This allows the development of different permit
requirements for each tested waste feed, which can be advantageous if the
facility anticipates that some of its wastes will be easier to burn than others.
If the trial burn results demonstrate that the incinerator meets performance
requirements for some waste feeds under less severe operating conditions (for
example, using lower combustion temperatures), then the permit can specify more
flexible operating conditions (a wider range of permissible combustion
temperatures) for these waste feeds. This flexibility may help reduce operating
costs of the incinerator.
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What happens if the incinerator does not neet the performance standards
the trial burn?
The trial burn involves the measurement of incinerator performance under
different sets of operating conditions. If the incinerator fails to meet these
performance standards, the incinerator design or operation must be modified, and
the trial burn must be repeated before the permitting process can proceed to the
next step. Thus, in the case of an interim status incinerator, the permitting
agency will not prepare a draft permit until the incinerator has been
demonstrated to meet performance standards u ier at least one set of operating
conditions .
For a new incinerator, the owner or operator will be required to apply for a
permit modification before a second trial burn can be conducted. In such cases,
the procedures used to evaluate the application for permit modification are very
similar to procedures for the issuance of the original permit, including
submission of a trial burn plan, development of a proposed modification by the
permitting agency, and allowance for ^public participation and comment before
issuance or denial of the modification. The permit will not be modified to
allow an additional trial burn unless the permitting agency is satisfied that
the incinerator will meet performance standards during the trial burn. Thus,
the application and new trial burn plan must address in some way (either through
changes in operating conditions or by modifications in equipment design) any
problems identified during the initial trial burn. For example, if the
incinerator failed to meet the standards for hydrogen chloride emissions, the
facility operator may modify the incinerator's air pollution control equipment
to improve its performance.
If the trial burn data indicate compliance with performance standards under
some, but not all, tested operating conditions, the permit applicant (in the
case of an interim status incinerator) or permit holder (in the case of a new
incinerator) may choose not to repeat the trial burn. In the case of an interim
status incinerator, the permit, if issued, will require that the incinerator
operate under the conditions demonstrated during the trial burn that resulted in
compliance with performance standards. For a new incinerator, the existing
permit will be modified to include only the conditions demonstrated during the
trial burn that resulted in compliance with performance standards. If, at any
time thereafter, the permit holder wishes to expand the range of allowable
operating conditions or waste feed types to allow greater flexibility, he or she
must seek a permit modification.
Do all incinerators perform trial burns?
RCRA standards allow permit applicants the option of submitting performance
data that can serve as a substitute for trial burn results. However, few RCRA
permits have been issued to date without the performance of a trial burn. All
permit applicants must demonstrate the ability of their incinerator to meet
performance standards or agree to perform a trial burn, either before the permit
is issued (for an interim status incinerator) or after (for a new incinerator).
If an applicant chooses to submit data in lieu of a trial burn, these data must
demonstrate the conditions under which the incinerator will achieve the minimum
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performance standards for specific wastes covered by the application. If the
data are not considered adequate, the permit writer requests the applicant to
submit other data or agree to perform a trial burn. Acceptable data are
therefore limited to performance data from similar or identical incinerators
that were burning similar or identical wastes to those covered in the
application. Applicants operating 4n interim status incinerator could develop
these data during normal operations j Applicants for a new incinerator might
submit trial burn data from an incinerator with identical design to the one
covered by the application.
Given that: new incinerators are untested, could the conduct of the trial
burn pose a serious risk to hunan health and the environment?
A trial burn is conducted to sho|w that the incinerator can operate in a
manner that protects nearby residents and the surrounding environment.
Therefore, during the trial burn, the incinerator will be operating only under
conditions that the permitting agenc'y judges will result in the incinerator
meeting the performance standards. Occasionally, an incinerator may fail to
meet the performance standards during a trial burn. The risk to the environment
and the public in such cases is minimal due to the short duration of these
tests.
To ensure that trial burns will be properly planned and executed, RCRA
standards require that the owner or operator of a new incinerator develop a
detailed trial burn plan. The plan proposes operating conditions for the trial
burn, provides a description of all emission control equipment to be used, and
explains the procedures for stopping the waste feed, shutting down the
incinerator, and controlling emissions in the event of any problems. The trial
burn plan is submitted with the permit application, reviewed by the permitting
agency, and is not approved unless tihe permitting agency judges that the
incinerator will meet all standards throughout the trial burn, and that any
departure from this expected level of performance will not pose an imminent
hazard to health or the environment.[
How are the results of the trial burn evaluated?
Within 90 days following the trial burn, the applicant must provide data
from the trial burn and analysis of [these data for each waste feed incinerated
during the trial burn. All data collected by the applicant must be submitted to
the permitting agency for evaluation. The 90-day period following the trial
burn allows time for analyzing both the samples collected and other pertinent
data. :
After the data have been submitted, the permit writer reviews the data to
determine whether the performance standards were met and under what range of
operating conditions. For each set-of operating conditions used during the
trial burn, the permit writer either calculates or reviews the applicant's
calculations for destruction and removal efficiency for each POHC, the
efficiency of the hydrogen chloride removal system if hydrogen chloride
emissions exceeded 4 pounds per hour, and the concentration of particulate
matter in stack emissions.
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How are the results of the trial burn reflected in the permit?
For each type of waste feed to be burned by the incinerator, the permit
specifies a set of operating conditions consistent with those conditions
demonstrated during the trial burn to result in compliance with the performance
standards. At a minimum, the permit specifies operating conditions for
combustion gas carbon monoxide levels, waste feed rate, combustion temperature>
combustion gas flow rate, and acceptable variations in the waste feed
composition. The operating conditions may allow for normal fluctuations in
these parameters that do not affect performance, as demonstrated during the
trial burn. For example, the combustion temperature specified in the permit can
be expressed as a range of values over which compliance with the performance
standards has been demonstrated. In addition, the permit writer may specify
other operating conditions deemed necessary to ensure compliance with the
performance standards.
After review of trial burn data from an interim status facility, the
permitting agency prepares a draft permit based on the trial burn results. For
a new facility, if the data from the trial burn show that the operating
conditions included in the permit for the final operating period are sufficient,
the facility may enter into this phase of operations. Otherwise, the permit
will require modification before this phase of operations may begin.
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CHAPTER 4
ENFORCEMENT OF PERMIT OPERATING CONDITIONS
After a permit is granted, the permitting agency must make sure that the-
facility complies with all permit conditions. Facility inspections are the main
tool by which federal or state officials monitor for compliance. An inspection
is a formal visit to a facility to review records, take samples, and observe
facility operations. EPA conducts inspections in all states, including those
states with their own RCRA programs. ! Authorized states will also have their own
inspection programs. Local authorities and local residents can also play a role
in making sure that facilities comply with RCRA regulations.
How will EPA or the state ensure that incinerator operation!; meet the
requirements of the permit:? }
The principal goal of the RCRA compliance monitoring and enforcement program
is to ensure that the regulatory and statutory provisions of RCRA are met. If,a
facility fails tp comply with all provisions of its permit, the permitting
agency has at its disposal various enforcement measures, including
administrative actions, civil actions, and criminal actions.
i
Administrative actions provide enforcement outside of the court system.
These actions may be informal, such as a phone call or letter notifying the
facility of a problem. Continued violation may necessitate a warning letter
that specifies the action required and that describes enforcement measures that
will be taken if the action is not taken by a specific date.
i
Besides these informal actions, the permitting agency can issue
administrative orders. These orders are legal documents that compel the permit
holder to take action in accordance with the terms of the permit, as indicated
in the administrative order. Administrative orders can assess penalties for
non-compliance and can suspend or revoke the permit (or interim status, if
applicable).
Civil actions are law suits that are either settled by negotiation or tried
in court. The permitting agency may pursue a civil suit when administrative
orders are ignored or where dangers to human health and the environment are
significant (for example, if non-compliance results in a release of hazardous
waste). Civil suits can seek penalties and suspension or revocation of the
permit or interim status. Criminal actions are pursued for the most serious
violations. Section 3008 of RCRA identifies seven violations that carry
criminal penalties. Penalties for six of the seven violations can include a
fine of up to $50,000 per day or a prison sentence of up to 5 years. The
seventh and most serious offense could include a penalty of up to $250,000 or 15
years imprisonment. An example of a [criminal violation is knowingly
transporting waste to a facility not jcovered by a permit or by interim status.
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tthat occurs during an inspection?
The main purpose of any inspection is to determine whether the facility is
operating in accordance with the terms of its permit. An inspection typically
consists of the following steps:
Before visiting the facility, the inspector reviews the
facility's permit and other ager y_records on the facility
to identify any problems that ma be encountered.
The inspector enters the facility, identifies himself or
herself, and describes the nature of the inspection. An
opening conference is held with the owner or operator to
describe the information and samples to be gathered.
The facility is inspected. The inspection includes
examination of facility records, possible collection of
samples, and observation 6f the facility including the
incinerator and any other hazardous waste management
operations. The inspector will also observe all
associated activities, such as unloading of wastes, lab
work, and safety procedures. The inspector may use field
notebooks, checklists, and photographs to document the
visit.
The .inspector holds a closing conference with the owner or
operator to respond to questions about the inspection and
provide additional information.
The inspector prepares a report summarizing the results of
the inspection, including the results of sampling.
Violations of the permit are documented in the report.
Inspections usually last between one day and a week.
If the facility is in violation of the permit, enforcement actions may be
taken. Enforcement actions can range from informal actions to criminal judicial
cases, depending on the severity of the violation. The severity is determined
by the likelihood that the violation will pose a threat to human health or the
environment. For example, some recordkeeping violations would be judged less
severe than operating violations that affect incinerator performance. The EPA
regional offices have broad discretion in these matters.
Why aren't: there government: inspectors at the facility at all tines, or at
least whenever the incinerator is operating?
To date, EPA has not exercised its authority under RCRA to require that
facilities accept a full-time inspector, or to require a facility to pay
expenses related to full-time inspectors. Other methods are used to ensure a
satisfactory inspection program. First, EPA's current inspection program uses a
variety of techniques to provide adequate monitoring of facility activities
without maintaining a full-time inspector at each facility. These techniques
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Include periodic Inspections (both announced and unannounced), interviews with
facility personnel, and frequent contacts and cooperation with state inspectors.
Second, the regulatory requirement that operating parameters be linked to
automatic waste feed shut-off is meant to ensure that the operating conditions
in the permit are maintained at all times. (See page 20 for an explanation of
automatic waste feed shut-off.) Thej incinerator control system must be designed
so that if operating conditions vary from the allowable ranges, all waste feed
to the unit is immediately cut off and the incinerator shuts down its
destruction activities. Third, in authorized states, incinerators are subject
to state enforcement authority and inspections. Some states, as part of their
enforcement program, require that inspectors be present at hazardous waste
management facilities at all times. The use of full-time inspectors is a matter
of state law in authorized states, atid is not part of the RCRA federal program.
How often will the facility be inspected by the permitting agency?
i
RCRA requires that all federal- (or state-operated facilities be inspected at
least annually and that all other hazardous waste generators and management
facilities be inspected at least once every 2 years. EPA has successfully
encouraged more frequent inspections. Inspections are scheduled by states and
EPA regional offices according to criteria that ensure greater attention to
facilities of greater concern. Inspections may also be conducted at any time
based on suspicion that a violation [is occurring. Finally, facilities may be
chosen for an inspection when specific information is needed to support the
development of additional RCRA standards.
F
Is the facility given notice before an inspection is made?
Normally, facilities are given notice of an upcoming inspection. Advanced
warning does not diminish the effectiveness of the inspection because the
primary purpose of a routine inspection is to examine ongoing facility records.
These records are generally more revealing of ongoing practices than
observations of facility operations on a single day. In cases where a facility
has or is believed to be violating the requirements of its permit, unannounced
and more frequent inspections are more common. The decision concerning notice
of an inspection is generally left t'o the discretion of the inspecting agency.
In terms of enforcement, will local authorities have any responsibility for
ensuring that the facility operates safely and in accordance with
regulations? ;
The permitting agency cannot delegate its enforcement responsibilities to
local authorities. Agencies at the local level, however, can play a significant
role in monitoring, facilities within their jurisdiction. To the extent that
local agencies actively enforce local regulations (for example, fire and safety
rules), are knowledgeable about RCRA requirements and about the activities being
carried out at the facility, these agencies can help ensure that an individual
facility operates safely and consistently within the conditions of its permit.
By sharing information with EPA or the appropriate state agency concerning
possible violations of requirements or possible hazards, local authorities and
citizens help in the enforcement effort.
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What, should local residents do if they have complaints about a facility or
wish to inform someone of something they have observed?
Citizens should contact the regional EPA office or the state environmental
agency to describe any problems they perceive (see page 44). EPA's or the
state's response to the complaint will depend on the potential severity of the
incident or condition involved. This response could range from an on-site
investigation of the problem to a telephone inquiry to the facility. EPA
welcomes the active participation of citizens on issues involving hazardous
waste, including formal and informal involvement in all aspects of permitting
and the enforcement of permits. The public is entitled to review reports, data,
and records maintained by EPA concerning a specific facility including, for
example, inspection reports. Some limited types of information received from
some facilities may be designated "Confidential Business Information" and will
not be available for review in order to protect trade secrets.
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CHAPTER 5
GENERAL STANDARDS FOR FACILITIES OPERATING
HAZARDOUS WASTE INCINERATORS
i
This section discusses the general standards that apply to all facilities
that treat, store, and dispose of hazardous wastes, including facilities
operating hazardous waste incinerators. The standards appear in Volume 40 Part
264 of the Code of Federal Regulations and were developed to ensure that these
facilities are properly designed, operated, and maintained. They include
provisions covering accident prevention, planning and equipment for emergencies,
waste transportation, waste testing land storage, recordkeeping, personnel
training, and insurance and closure requirements, among other topics.
This chapter also describes specific standards for tanks and containers.
Tank and container standards are included because these types of units are more
commonly used in association with incinerators than other types s(for example,
surface impoundments and waste piles). Facilities operating other types of
hazardous waste management units are1 subject to specific standards for these
units. For information on these standards, contact the EPA regional office for
your area (see page 44). i
The chapter provides information on the following topics:
I
The safe transportation ;of hazardous waste to the
facility; j
Prevention of spills and leaks during storage;
Requirements for handling incompatible, reactive, and
ignitable wastes; '
Management of treatment .residues;
Routine inspections of the facility and training of
employees; !
Procedures and requirements that protect the public and
facility personnel in the event of a spill or an emergency
at the facility;
I
Liability insurance; :
!
Protection from floods; (
Measures required for the maintenance of security; and
Procedures required when the facility ceases operations.
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TRANSPORTATION AND STORAGE OF WASTES
What: regulations ensure that hazardous wastes will be transported safely to
the incinerator facility?
Transporters of hazardous waste are regulated jointly by EPA under RCRA and
by the Department of Transportation (DOT) under the Hazardous Materials
Transportation Act (HMTA). Under HMTA, DOT ha set standards for the
transportation and labeling of shipments of ha: rdous materials, including
hazardous waste. These standards cover shippin6 containers and labeling;
placarding of vehicles; design, construction, and maintenance of containers (for
example, tanks); and the use of shipping papers. Under the Motor Carrier Act,
DOT has developed additional standards for driver qualifications and training as
well as the design, construction, and maintenance of vehicles.
RCRA standards require that each hazardous waste transporter obtain an
identification number before it can legally accept wastes for shipment (except
in certain emergency situations). Transporters are required to take immediate
action to notify the proper authorities if an accident causing a release of
hazardous waste occurs, and are liable for the cost of cleaning up any spills
that may occur. RCRA standards also require use of a special manifest form
(acceptable under HMTA standards for shipping papers).
The RCRA manifest system allows tracking of individual waste shipments. The
generator fills out a manifest form that designates a final destination point
for the waste (for example, a specific incinerator facility). Each time the
shipment changes custody (generator to transporter, transporter to incinerator
facility), the manifest is signed to acknowledge the transfer of custody and a
copy is retained by each party. When the shipment reaches the designated
facility, the owner or operator of the facility must send a copy of the
completed manifest to the generator. If the generator does not receive a copy
of the manifest, the generator must contact the transporter and the designated
facility. If, after 45 days, the generator still does not receive the completed
manifest, the generator must contact EPA. The manifest system allows EPA to
keep track of wastes that are accidentally spilled and helps to prevent illegal
disposal practices, such as "midnight-dumping."
Will problens occur because of the storage of wastes before incineration?
At any facility where hazardous waste is stored, there is a possibility of
leaks and spills. When wastes are stored or transferred from one storage vessel
to another, for example, small amounts of vaporized pollutants may be released.
These releases are referred to as fugitive emissions. These emissions will
occur at all sites at which hazardous wastes are managed, including incinerator
sites. To ensure that problems do not occur during storage of wastes, RCRA
regulations require that the facility be designed, constructed, operated, and
maintained to minimize the possibility of releases and to prevent accidental
releases from causing adverse health or environmental effects. Hazardous wastes
destined for incineration are typically stored in containers or tanks.
Containers are generally portable and can be sealed to prevent the release of
vapors, dusts, or liquids. Common containers for storing hazardous waste
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i
Include hoppers and metal drums. Standards for hazardous waste containers
require that containers be inspected weekly and that the contents be transferred
from any container found in poor condition. Containers must be closed during
storage and can only be opened when wastes are being sampled or transferred to
or from the containers. Containers must be stored in areas with "secondary
containment" (that is, areas in which any leaks or spills will be safely held
until they can be cleaned up). '
Tanks are stationary structures that are designed, constructed, and
maintained as part of the facility[ They may be installed above or below
ground. For each tank, the facility must obtain certification from a registered
professional engineer that the tank will withstand expected physical and
chemical stresses. A corrosion expert must also certify that tanks with
external portions in contact with soil or water will withstand this contact
throughout the period during which the tanks will be used. All tanks must be
equipped with a secondary containment system (a structure that holds potential
leaks or spills until they can be cleaned up). These systems must be designed
so that leaks or failure of the tank or the secondary containment system itself
are detected within 24 hours. RCRA standards require daily inspections of
tanks. I
HANDLING OF WASTES AT THE FACILITY
What: happens to a shipnent of waste from the time it arrives at the
facility until the tine it is incinerated?
Before a facility may treat or' accept a waste for management, it must
perform a detailed chemical and physical analysis to ensure that the waste may
be managed under the conditions of its permit and to determine the proper method
of managing the waste. These procedures are fully described in the facility's
Waste Analysis Plan, which is a part of its permit application and which is
incorporated by reference in the facility permit. Subsequent shipments of the
same waste must be sampled and examined, and detailed analyses performed if
there is any reason to believe that the waste's characteristics have changed.
In any case, the facility can accept wastes only if the wastes are allowed under
its permit conditions. Otherwise,!it must refuse to accept the waste and the
shipment must be returned to the generator. In the event that a waste shipment
deviates either from the specifications of the accompanying manifest or from
characteristics expected from earlier analyses, the facility must follow
procedures specified in the Waste Analysis Plan for resolving the discrepancy.
I
Once a shipment of waste has been accepted, it may be stored at the facility
before being incinerated. The period of time a waste is stored before
incineration varies. Facilities handling various waste types which must be
incinerated separately may store a particular waste until enough has accumulated
to justify a continuous burn. In some cases, wastes may be blended together or
treated (for example, metals removed) prior to incineration. Any storage,
treatment, or blending of wastes will be fully addressed in the facility's
permit.
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How does a facility keep track of all the different types of wastes it
receives so that incompatible, reactive, or ignitable wastes are handled
properly?
The facility's Waste Analysis Plan must ensure that the facility
perform any necessary analyses to determine which wastes are incompatible,
reactive, or ignitable. The plan also specifies the measures to be taken if
such wastes are identified. Mixing or other contact between incompatible wastes
may produce heat or pressure; fire or explosion; violent reaction; toxic dusts,
mists, fumes, or gases; or flammable fumes or gases. RCRA standards prohibit
storage or treatment of incompatible wastes in the same container or tank unless
the wastes are mixed according to a proven, safe procedure. If a waste is to be
placed into an empty tank which previously held an incompatible waste, the tank
must first be cleaned. Incompatible wastes stored or treated near each other
must be placed in container areas or tanks having separate secondary containment
systems .
RCRA standards include explicit criteria for identifying ignitable and
reactive wastes. Ignitable wastes include liquid wastes with flash points less
than 140°F; non-liquid wastes that under standard pressure and temperature could
cause fires through friction, absorption of moisture, or spontaneous chemical
changes; certain compressed gases; and oxidizers. Reactive wastes generally are
those that react violently; form potentially explosive mixtures; produce toxic
vapors, gases, or fumes in the presence of water; or undergo detonation or
explosive reaction when exposed to a strong initiating source.
Ignitable and reactive wastes must be separated and kept away from sources
of ignition or reaction during storage. Wastes that are unstable at normal
temperatures may be cooled during storage. Tanks and auxiliary piping systems
for the storage of water -reactive wastes are designed to eliminate the
possibility of water being introduced accidentally to the tanks. Ignitable and
reactive wastes may be handled only in areas where smoking and open flames are
prohibited. Containers with ignitable or reactive waste must be located a
minimum of 50 feet inside the facility's property line. For tanks storing these
wastes, the facility must follow the National Fire Protection Agency's
"Flammable and Combustible Liquids Code" to determine the minimum safe distance
from public ways, streets, alleys, or adjoining property.
How are treatment residues, such as ash from the incinerator, managed?
All residues from hazardous waste treatment are considered, by regulation,
to be hazardous. Incineration byproducts, including ash and any wastewaters
from cooling or air pollution control devices, are therefore subject to the
requirements governing transportation, treatment, storage, and disposal of
hazardous wastes. Incinerator ash is generally disposed in a hazardous waste
landfill. Wastewaters are often disposed through the sewer system or discharged
to a river or stream. In these cases, the wastewaters must be managed according
to Clean Water Act standards, as well as RCRA standards, before discharge.
Disposing of wastewaters in streams and rivers requires a National Pollution
Discharge Elimination System (NPDES) permit. These permits place restrictions
on the quantity of wastewaters released, the level of pollutants in the water,
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and other characteristics (such as temperature) To meet these requirements,
the facility may treat its wastewaters before disposal. Disposal through the
sewer system may also require that the wastewaters be treated to meet Clean
Water Act standards. \
,
RCRA standards allow for exemptions to the requirements that treatment
residues be managed as hazardous wastes. If the owner or operator of the
facility can prove to EPA that the byproducts are not hazardous, the owner or
operator can obtain an exemption from these requirements. This exemption,
called a delisting, is issued by EPA on a case-by-case basis. Regardless of
whether the wastewaters are considered hazardous or not, if they are to be
disposed by release to a stream or river or through the sewer, the owner or
operator must comply with the Clean;Water Act.
INSPECTIONS AND TRAINING
How will equipment malfunctionsfor other problems be detected?
i
RCRA standards require that all monitoring equipment, safety and emergency
equipment, and operating and structural equipment which prevents, detects, or
responds to spills or releases be inspected by the owner or operator according
to a written schedule. The inspection frequency for each item depends upon its
expected rate of deterioration and the probability of adverse effects to nearby
residents or the environment should the item fail. The inspection schedule is
submitted with Part B of the permit:application and is incorporated by reference
into the permit. j
Loading and unloading areas, and other areas where spills may occur, must be
inspected daily when in use. Tank systems must be inspected daily, while
container storage areas must be inspected at least weekly for leaking containers
and deterioration of containers and;containment systems. The data from
monitoring and leak detection equipment must be reviewed on a daily basis.
Deterioration or malfunctions must be remedied immediately if a hazard is
imminent or already exists. If there is no imminent hazard, the situation must
be remedied on a schedule that ensures that there is no harm to nearby residents
or to the environment. f
Will employees be able to recognize and respond quickly to problems?
RCRA standards require that facility personnel be trained to perform their
jobs safely and to respond properly to both emergencies and more routine
problems. Employees must know the procedures for emergency shutdown of
operations and understand the operation of the incinerator's automatic waste
feed shut-off system. They must be.trained in the use of alarm and
communications systems and trained to respond to fires,' explosions, spills, and
leaks. Personnel must also be trained to inspect, repair, and replace emergency
and monitoring equipment. ;
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Employees must complete their training within six months of employment at
the facility or assignment to a new position. Employees may not work
unsupervised until training is complete. All personnel must take annual review
courses. An outline of the training program and a description of how the
program will correspond to actual job tasks must be included with Part B of the
permit application and is included as a part of the facility permit.
SPILLS AHD EMERGENCIES
What: if leaks or spills occur that nobody notices?
Areas where spills or leaks are likely to occur are frequently inspected
according to a set schedule. Thus, a spill, if undetected at the time it
occurs, will be detected soon after. Areas where wastes are transferred or
stored must have spill containment systems. These systems facilitate clean up
and help prevent adverse consequences from spills. Detection of leaks can be
aided by automatic leak detection systems, and backed up by manual inspections.
Automatic leak detection equipment and spill containment systems are frequently
inspected to ensure their integrity.
What if spills occur during the transfer of wastes from truck to tanks or
other storage containers?
If spills occur, they must be cleaned up as soon as possible. To contain
any spills that occur, loading and unloading areas must be designed to collect
liquids and must have a base impervious to liquids. Large spills collect in a
slump and may be cleaned up by pumping the waste into containers. Small spills
can be picked up with an absorbent material designed specifically for use with
hazardous waste. The chances of a spill are probably greatest when wastes are
transferred from one container to another. Spills can be prevented, however,
with a combination of strict procedures, training of personnel, and good process
design, all of which are covered in the permit. Spill prevention procedures
include draining liquids and bleeding pressure from connection lines before
wastes are transferred.
How do facilities plan ahead in case of an emergency, such as a fire or
explosion?
Every hazardous waste incineration facility must regularly inspect and
maintain emergency equipment, such as fire extinguishers and sprinklers, and
have adequate alarm systems for notifying facility personnel of emergency
situations. All facilities are required to have an evacuation plan. This plan
is part of the facility's Contingency Plan for responding to emergency
situations. The Contingency Plan is a required part of Part B of the permit
application and is incorporated by reference into the permit.
A copy of the Contingency Plan must be maintained at the facility and copies
must be distributed to all local officials who may be involved in emergency
response. The plan must inform police, fire departments, and emergency response
teams of the facility layout; identify the characteristics of the hazardous
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astes present; describe the hazards associated with the wastes and the
recesses in use; indicate the probable location of employees during normal
perations; and designate personnel1evacuation routes from the facility. The
Ian must designate one fire department as the primary authority in an emergency
or which such assistance is required. The plan also describes the actions
acility personnel will take in the event of an emergency.
i
The plan must contain the names i, addresses, and phone numbers of facility
ersonnel qualified to act as "emergency coordinators." The emergency
oordinator has the authority to take any action necessary to carry out the
ontingency Plan and must be knowledgeable of the plan, all operations and
ctivities at the facility, the location and characteristics of all wastes, and
he location of all records within the facility. A designated emergency
oordinator must be at the facilityJor on call at all times.
I
What will happen if an emergency occurs?
If a release, fire, or explosion occurs, the emergency coordinator must:
Alert facility personnel;
Notify local agencies if their help is needed;
j
Identify the character, amount, source, and extent of any
releases; and ;
Assess possible hazards to human health and the
environment. I
i .. .
f the coordinator determines that a threat exists, the appropriate officials
tust be advised on whether surrounding areas should be evacuated. Measures must
e taken to ensure that fire or explosion does not recur, or spread to other
astes. After the emergency, released wastes and, materials contaminated with
eleased wastes must be recovered and stored for proper treatment or disposal.
i
How will individuals or the community be compensated for any negative
effects of accidents at the facility?
RCRA regulations require that owners or operators be financially responsible
or both sudden and non-sudden accidental occurrences due to operations at a
acility. All owners or operators must carry liability coverage to compensate
ndividuals for bodily injury or prpperty damage caused by sudden accidental
ccurrences. Owners or operators of facilities with one or more landfills,
urface impoundments, or land treatment units must also have liability coverage
or non-sudden accidental occurrences.
f
How will the facility be secured from vandals or unauthorised visitors?
The active areas of the facility must be completely enclosed by a fence or
lome combination of artificial and natural barriers that restricts entry.
Jntrance to the active, enclosed areas must be controlled and monitored at all
:imes.
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CLOSING THE FACILITY
What will happen to the site when the facility ceases operations?
When the facility or any single waste management unit at the facility ceases
operations, the facility or unit will be "closed" in accordance with a plan that
has been approved by EPA. For a permitted facility, the closure plan is
submitted with Part B of the permit application and becomes a part of the
permit. For an interim status facility, the owner or operator submits a plan to
EPA before closure begins. EPA makes this plan available to the public for
comment. Following the comment period, EPA may decide to approve, modify, or
disapprove the plan. For both interim status and permitted facilities, the plan
details a set of actions and sets a timetable for closure. Following the
completion of all plan activities, the owner or operator and an independent,
registered professional engineer must certify that the facility has been
properly closed.
Closure involves all aspects of the facility's waste management operations.
For a facility operating only storage and incineration services, closure would
involve the removal and proper disposal elsewhere of any wastes or waste
residues. 'It also would require decontamination or proper disposal elsewhere of
all structures in which wastes were handled and any equipment that came into
contact with wastes, such as blending and storage tanks and the incinerator
itself. Because incineration is a treatment rather than a disposal process,
closure of an incinerator would result in the removal of all Tiazardous wastes
from the site, and continued care measures would not be required. If there were
spills or other types of contamination at the incinerator site that could not be
adequately removed at the time of release, long term clean up measures
(corrective action) would be required.
How does RCRA ensure that the owner/operator has funds available for
closure?
RCRA regulations establish financial requirements to ensure that funds are
available to pay for closing a facility. For closure, owners or operators must
prepare a written cost estimate for closing the facility. These estimates must
reflect the actual cost of conducting all the activities outlined in the
facility's closure plan, and are adjusted annually for inflation. The cost
estimate for closure is based on the point in the facility's operating life when
closure would be the most expensive. Following preparation of the closure cost
estimate, the owner or operator must demonstrate to EPA the ability to pay the
estimated amounts. This is called financial assurance for closure. RCRA
regulations describes several mechanisms for guaranteeing financial assurance
for closure activities, including use of a trust fund, or a letter of credit,
among others. All mechanisms require annual adjustments for inflation or
changes in cost estimates. If, for any reason, the owner/operator should
declare bankruptcy and does not provide funds for closure, EPA would become one
of the facility's creditors to obtain these funds.
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I CHAPTER 6
POTENTIAL RISKS OF HAZARDOUS WASTE INCINERATION
i
Hazardous waste incineration, like other industrial operations, -is not
without risk. Some risks are associated with incineration itself; others are
associated with related operations^ such as the transportation and storage of
the hazardous waste. RCRA requires EPA to examine risks that could be
associated with activities involving hazardous wastes and to develop standards
that protect human health and the environment. This chapter outlines the risks
associated with hazardous waste incineration and briefly describes the standards
developed by EPA and other agencies. Chapters 2 through 5 provide more detailed
information on the specific requirements of RCRA standards.
Do emissions from hazardous waste incinerators cause health and
environmental problems? j
j
EPA believes that a well-designed and properly-operated incinerator will not
cause health or environmental problems. Based on the best available information
concerning the risks of incineration, EPA has developed standards that place
strict limits on the quantities of i pollutants in emissions from hazardous waste
incinerators.
i
Hazardous waste incinerator emissions contain small quantities of metals and
uncombusted organic compounds. The organic compounds consist of trace levels of
the organic compounds in the hazardous waste feed as well as products of
incomplete combustion (PICs) , formed during the combustion process. EPA
standards limit emissions of designated organic compounds in the waste (called
principle organic hazardous constituents, or POHCs) and particulate matter. To
ensure that emissions of total residual organic compounds and metals are
minimized to acceptable levels, EPA is developing regulations that would
strengthen the existing controls to directly regulate these emissions. In the
interim until those regulations are promulgated, permit writers can implement
the controls on a case-by-case basis as necessary to protect human health and
the environment. !
F
How are risks from hazardous waste incineration estimated?
Potential human health risks cbn be measured using risk assessment
techniques. Risk assessment uses Established methods to evaluate the
relationship between exposure to tbxic substances and the subsequent occurrence
of disease. A thorough risk assessment considers not only possible risks from
day-to-day operation, but also risks caused by abnormal operation ("upset"
conditions), and accidents. Some risk assessments involve fairly simple
calculations using conservative screening values to determine worst-case risks,
while others involve complex computer models. EPA has developed air dispersion
models and health effects data for> use in risk assessment. EPA is continuing to
update this information and to devjelop further guidance in the area of risk
assessment.
Risk assessment of hazardous wlaste incineration examines two factors--the
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41
toxicity of the pollutants emitted from the incinerator, and the magnitude of
exposure of humans to these pollutants. Toxicity is a measure of the type of
adverse effects a pollutant may cause in humans or other species. Exposure is
the estimated amount of human contact with the pollutant that occurs. A risk
assessment estimates the probability of adverse health effects occurring as a
result of human exposure to a pollutant with a specified toxicity.
To measure the health risk from hazardous waste incinerator emissions,
several steps must be taken. The first step is to measure emissions or to
estimate them based on the incinerator's technical specifications (destruction
and removal efficiency or DRE) and the types ai quantities of waste to be
burned in the incinerator. To predict the concentration of pollutants in the
air, models can be used that account for dilution and dispersion of the
pollutants as they move away from the incinerator. Based on estimates of
pollutant concentrations at various locations, it is possible to determine the
maximum pollutant concentration. Using conservative assumptions (for example,
lifetime exposure to the maximum pollutant concentration) and toxicological
data, health risks can then be identified and quantified.
Do risk assessnents ever underestinate or overestimate risks?
Risk assessments always involve assumptions' and thus include some degree of
uncertainty. These assumptions influence the outcome of the risk assessment; if
the assumptions are conservative, the risk assessment will tend to overestimate
risks. Both conservative and nonconservative assumptions are commonly used. An
example of a nonconservative assumption is that synergism between compounds does
not occur (that is, compounds do not interact to cause risks greater than the
sum of the risks from exposure to each individual compound). Conservative
approaches often used in risk assessment include basing risk estimates on
lifetime exposures at the point of maximum ground level concentrations of
pollutants (essentially assuming that individuals are exposed to the maximum
concentrations for 70 years) and using safety factors so that risk estimates
reflect risks to the most sensitive people (that is, the people most likely to
experience effects from exposure). On balance, EPA risk assessments are
conservative by design, and will tend to overestimate risks.
Uhat are the risks from hazardous waste Incineration?
Reasonable, worst-case estimates of health risks posed by metals and organic
compounds in emissions for a permitted hazardous waste incinerator range from
one chance in 100,000 to one chance in 100,000,000 of contracting cancer over a
lifetime. These conservative estimates assume 70 years of continuous exposure
at the point where pollutant concentrations would be the highest.
To put the above figures into context, the death rate from motor vehicle
accidents in 1986 was 19.6 per 100,000 population, or approximately one chance
in 100 lifetime risk.^ For various regulatory purposes, EPA has considered
acceptable risk levels for hazardous waste regulatory programs to range from a
lifetime risk of one chance in 10,000 to one chance in 10,000,000. Levels of
1 The World Almanac and Book of Facts. 1988; Editor, Mark S. Hoffman.
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acceptability vary depending on the
of activities associated with the
How do EPA performance standa
42
nature of the risks involved and the types
risk.
protect human health?
EPA sets performance standard^ to control the amount of pollutants which are
emitted from hazardous waste incinerators. EPA's principal measure of
performance is destruction and removal efficiency (see chapter 2 for a more
detailed discussipn). A 99.99 percent ORE means that one molecule of a chemical
is released to the air for every 10,000 molecules entering the incinerator.
These performance standards set limits on the amount of pollutants allowed in
emissions, given the amount of waste which is burned. Only a very small
percentage of toxic substances origir lly contained in the waste can be released
into the air. EPA has done numerous .tudies which indicate that incinerators
meeting EPA's performance standards pose no significant health hazards.
s.
[
EPA's current incinerator regulations also include performance standards
limiting the amount of particulate'matter and hydrogen chloride emitted. As
discussed above, EPA is in the pr^> risk assessments in support of their permit
applications. Permit writers have the authority to require more stringent risk-
based operating conditions in the permit when necessary to provide adequate
protection of human health and the;environment, in addition to operating
conditions required to meet regulatory performance standards. Although EPA
believes that hazardous waste incinerators meeting performance standards will
not cause health or environmental problems, a permit writer may occasionally
require additional safeguards to provide extra assurance that problems will not
occur. I
What are the risks involved during the transportation of hazardous waste to
the site? I
i
Activities involving the handling of hazardous wastes always involve some
risk that wastes will be released to thfe environment. These are the same types
of risks that are involved in the transportation of chemicals to industrial
plants. Hazards can be reduced through proper planning, use, and maintenance of
equipment, and development of safety-oriented procedures. Among the potential
hazards are releases caused by accidents while transporting the hazardous waste
to and within the facility, and leaks and spills during the transfer of wastes
to and from the vehicle. |
i .
EPA requirements for transporters cover emergency procedures and the use of
a special form, called a manifest, that allows the tracking of individual waste
shipments. RGRA standards require|transporters to take immediate action to
notify the proper authorities if an accident causing a release of hazardous
waste occurs. Transporters are liable for the cost of cleaning up any spills
that may occur. Transporters thatjfail to handle waste properly are subject to
financial penalties. In addition,|RCRA standards require procedures that
minimize the chance of leaks or spills occuring during transfer of wastes, and
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which ensure that leaks and spills that do occur are quickly and safely cleaned
up. Transporters of hazardous waste are also required to follow Department of
Transportation (DOT) standards. (For more information on DOT standards see
Chapter 5.)
Vnat are the chances of a fire or explosion occurring?
Fires and explosions are always possible at any industrial facility, such as
a petroleum refinery, where ignitable, pressurized, or reactive substances are
present. All incinerators require the use of fuel; in addition, some of the
wastes being treated may be ignitable or reactive. RCRA standards ensure proper
handling, storage, and incineration of such wastes so that there is very little
chance of fire or explosion. For example, standards require isolating ignition
sources from ignitable hazardous waste during storage and prohibit mixing
incompatible substances. Incompatible wastes must be stored and treated
separately so that there is no possibility of accidental mixing.
Department of Transportation regulations outline procedures for safe
packaging, handling, and storage of ignitable and reactive wastes that are
transported. Applicants for a RCRA permit are also required to provide a
complete chemical analysis of wastes they propose to incinerate, to use
engineering controls to monitor operation, and to develop contingency plans and
institute emergency response procedures that ensure quick and appropriate
measures in response to incidents at the facility. Facilities must provide the
local police and fire departments with information on the types of waste that
are handled. RCRA contingency planning and emergency response procedures are
discussed in greater detail in Chapter 5.
Title III of the Superfund Amendments and Reauthorization Act (SARA) of 1986
established a regulatory program entitled the "Emergency Planning and Community
Right-to-Know Act." The Act requires facilities to disclose information about
hazardous chemicals handled at the facility. This law also mandates the
formation of State Emergency Response Commissions and Local Emergency Planning
Committees. These groups are responsible for formulating emergency response
plans for chemical mishaps.
9hat if there is a. bad stor» or flood at the facility?
Storms, floods, or other natural disasters have the potential to damage any
structure or facility. In the case of hazardous waste incinerator facilities,
RCRA regulations define standards ensuring containment of hazardous wastes in
the event of certain natural disasters. A facility located in a 100-year
floodplain (an area that has a 1 percent or greater chance of being flooded in
any given year) is required to be designed, constructed, operated, and
maintained to prevent release of hazardous wastes should a flood occur. In
addition, the facility permit will require stormwater management techniques to
ensure that any stormwater that enters areas where wastes are handled is
collected, tested, and treated as necessary before being disposed.
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CONTACTS FDR FURTHER INFORMATION
RCRA/Superfund Hotline
Toll Free: (800) 424-9346
In the Washington D.C. area:
382-3000
EPA Regional Offices
Region I
Region II
Region III
Region IV
Region V
Region VI
Region VII
Region VIII
Connecticut, Maine,
Massachusetts, New
Hampshire, Rhode Island,
Vermont !
[
New Jersey, New York,
Puerto Rico, Virgin
Islands '
Delaware, D.C., Maryland,
Pennsylvania, Virginia,
West Virginia
Alabama, Florida,: Georgia,
Kentucky, Mississippi,
North Carolina, South
Carolina, Tennessee
Illinois, Indiana,
Michigan, Minnesota, Ohio,
Wisconsin
Arkansas, Louisiana,
New Mexico, Oklahoma,
Texas i
Iowa, Kansas, Nebraska,
Missouri
Colorado, Montana, North
Dakota, South Dakota,
Utah, Wyoming >
EPA
John F. Kennedy Federal Bldg.
Boston, MA 02203
(617) 573-9644
EPA
26 Federal Plaza
New York, NY 10278
(212) 264-8682
EPA
841 Chestnut Street
Philadelphia, PA 19107
(215) 597-7940
EPA
345 Courtland Street, NE
Atlanta, GA 30365
(404) 347-3433
EPA
230 South Dearborn St.
13th Floor - (HR-11)
Chicago, IL 60604
(312) 353-0398
EPA
First International Building
1201 Elm St.
Dallas, TX 75270
(214) 655-6785
EPA
726 Minnesota Ave.
Kansas City, KS 66101
(913) 236-2888
EPA
One Denver Place - Suite 1300
999 18th Street
Denver, CO 80202-2413
(303) 293-1676
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Region IX Arizona, California,
Hawaii, Nevada, American
Samoa, Guam
Region X Alaska, Idaho, Oregon,
Washington
EPA
215 Fremont St.
San Francisco, CA 94105
(415) 974-8026
EPA
1200 Sixth Ave.
Seattle, WA 98101
(206) 442-1099
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REFERENCES
U.S. Environmental Protection Agency, Office of Policy Planning and
Evaluation. March, 1985. Assessment of Incineration as a Treatment
Method for Liquid Organic Hazardous Wastes.
U.S. Environmental Protection Agency, Office of the Administrator,
Science Advisory Board. April, 1985. Report on the Incineration of
Liquid Hazardous Wastes by I the Environmental Effects. Transport, and
Fate Committee. Science Advisory Board.
Office of Technology Assessment, Congress of the United States. March,
1985. Technologies and Management Strategies for Hazardous Waste
Control.
American Society of Mechanical Engineers. Forthcoming in May, 1988.
Hazardous Waste Incineration: A Resource Document.
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GLOSSARY
Administrative order: An official, legally enforceable order issued by EPA to
force a facility's owner or operator to address potential threats to human
health and the environment resulting from activities at the facility.
Administrative orders can be used to force a facility to comply with
specific regulations, to take corrective action, and -to perform monitoring
testing, and analysis.
Administrative record: All information gathered .regarding an EPA action,
including public comments. EPA makes decisions based on the information
contained in the administrative record.
afterburner: The secondary combustion chamber of a rotary kiln incinerator.
air pollution control devices: Mechanisms or equipment which "clean"
emissions generated by an incinerator. These devices remove pollutants
(particulate matter, acid gases) that would otherwise be released to the
atmosphere.
automatic waste feed shut-off system: A device that automatically stops the
feeding of waste to an incinerator when it is not operating according to
conditions specified in the facility's permit. These operating conditions
(for example, temperature, carbon monoxide levels, waste-feed levels) are
constantly monitored for deviations from the allowable ranges specified in
the permit.
baghouse filtration: An air pollution control method in which emissions
containing tiny particles (particulate matter) are passed through a
filter. The filter is specifically designed to capture and prevent
release of particulate matter to the atmosphere.
Best Demonstrated Available Technology (BOAT): As identified by EPA, the most
effective commercially available means of treating specific types of
hazardous wastes. The BDAT for a particular waste may change in the futur
as new advances in treatment technologies are made.
biological treatment: The use of microorganisms (for example, bacteria) to
consume and break down organic wastes. Liquids containing organic wastes
are often mixed with oxygen, promoting both the growth of the
microorganisms and their consumption of organic materials.
chemical treatment: A broad category of hazardous waste treatment processes
that use chemicals to remove dissolved inorganics or transform waste
components to less toxic forms.
Code of Federal Regulations (CFR): A series of documents that contain all
regulations developed and finalized by government agencies. RCRA
regulations are contained in Volume 40 of the Code of Federal Regulations.
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combustion: The controlled burning of wastes. During combustion, heat is
used to chemically alter the organic compounds in the waste. Combustion
converts most of the organic compounds into stable inorganic compounds,
such as carbon dioxide and watfr.
i
combustion chamber: The actual com] artment (chamber) where wastes are burned
(combusted) in an incinerator.'
I " .
delisting: A process whereby a type of waste that is listed as hazardous
by EPA can be excluded from hazardous waste regulation. If the generator
can demonstrate that a particular waste does not pose risks to human health
and the environment, the waste can be delisted.
destruction and removal eff iciency: (DEI : A percentage that represents the
number of molecules of a compound emoved or destroyed in an incinerator
relative to the number of molecules of the compound which entered the
incinerator system. A DRE of 99.99 percent means that 9,999 molecules of a
compound are destroyed for every 10,000 molecules that enter the
incinerator. A DRE of 99.99 is referred to as "four nines."
dibenzofurans: A group of highly toxic organic compounds for which RCRA
regulations set more stringent destruction and removal efficiencies
(99.9999, or "six nines") than the DRE required for most other organic
compounds (99.99, or "four nines")
dioxins: A group of highly toxic b ganic compounds that are often found in
herbicides. RCRA regulations|require a higher destruction and removal
efficiency (99.9999) for dioxins than the DRE required for most other
organic compounds (99.99).
draft permit: A preliminary permit drafted and published by EPA. The draft
permit is subject to public review and comment before EPA takes final
action on a permit application.
electrostatic precipitators: Air pollution control devices that use
electrical charges to remove particulate matter from emission gases. The
process is similar to picking;up metal filings or needles with a magnet.
I
enforcement: Action that may be taken by EPA to ensure that an owner or
operator of a hazardous wastetmanagement facility is complying with
operating conditions specified in the facility's RCRA permit. EPA's
compliance monitoring and enforcement program includes inspections of
facilities and penalties against violators.
Environmental Impact Statement (EIS): A detailed report on the possible effects
that a pending structure or development will have on the environment. An
EIS must be .prepared by 'a government agency when a "major" federal action
that will have "significant" environmental 'impacts is planned.
fact sheet: A document prepared by EPA to inform the public about the
permitting process and EPA's tentative decision with regard to a
permit application. \
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Federal Register: A document published daily by the federal government
containing notification of government agency actions. The Federal
Register contains notification of EPA actions, including notification
of EPA decisions concerning permit applications.
financial assurance for closure: Documentation or proof that an owner or
operator of a facility is capable of paying the projected costs of closing
his or her facility. RCRA regulations require a hazardous waste management
facility owner or operator ta provide financial assurance in the form of a
trust fund, letter of credit, or similar financial mechanism.
flash point: The lowest temperature at which the vapors above a volatile
substance ignite in air when exposed to flame.
fluidized bed Incinerators: A type of incinerator which uses a bed of hot
sand or other granular material to transfer heat directly to waste,
resulting in waste destruction. Currently, these incinerators are used
mainly for municipal sludge.
fugitive ealssions: Releases of vaporized pollutants to the atmosphere that
occur at all sites at which hazardous waste is managed. Fugitive emissions
can occur when vapors are vented from containers or tanks where hazardous
wastes are stored. Fugitive emissions can also be caused by spills
occurring during the unloading of hazardous wastes from vehicles that
transport the waste, leaks through pipes and valves, and through operation
of faulty equipment.
hazardous wastes: Wastes exhibiting any of the following characteristics:
ignitability, corrosivity, reactivity, or EP-toxicity (yielding toxic
constituents in a leaching test). In addition, EPA has listed as hazardous
other wastes which do not necessarily exhibit these characteristics.
Although the legal definition of hazardous waste is complex, the term more
generally refers to any waste that EPA believes could pose a threat to
human health and the environment if managed improperly. RCRA regulations
set strict controls on the management of hazardous waste.
HSWA: Hazardous and Solid Waste Amendments of 1984. These amendments to RCRA
greatly expanded the scope of hazardous waste regulation. In HSWA,
Congress directed EPA to take measures to further reduce the risks to human
health and the environment caused by hazardous wastes.
inert: Lacking the ability to chemically react with other substances.
inorganic conpounds: Compounds that either do not contain carbon or do not
contain hydrogen along with carbon. Inorganic compounds include metals,
salts, and various carbon oxides (carbon monoxide, carbon dioxide). These
compounds do not combust in incinerators, although incinerators may
generate inorganic compounds.
interim status: A legal classification which applies to hazardous waste
incinerators or other hazardous waste management facilities that were under
construction or in operation by November 19, 1980, and can meet other
interim status requirements. Interim status facilities may operate without
a permit until EPA has made a final decision on the permit application.
EPA is required to approve or deny incinerator permit applications for
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public notice: Notification by EPA informing the public of Agency actions, for
example, the issuance of a draft permit. For draft permits, EPA must
follow procedures to ensure proper public notice, including publication of
the notice in newspapers and broadcast of the notice over radio stations.
I
pyrolysis: A method of thermal treatment that first uses high temperatures in
an oxygen-free chamber to transform inorganics into more easily handled
forms, and then uses a high temperature oxygen-containing chamber for
combustion of organics.
quench chamber: A common type of gas-cooling device in which heated gases are
mixed directly with water. ,
I
RCRA: Resource Conservation and Recovery Act of 1976. An amendment to the
first federal solid waste legislation, the Solid Waste Disposal Act of
1965. In RCRA, Congress established initial directives and guidelines for
EPA to regulate hazardous wastes.
response to contents: A document that addresses all significant public
comments received by EPA during the public comment period. The document
includes a summary of each comment as well as EPA's response to each
comment.
risk assessment: The use of established methods to measure the risks posed by
an activity such as hazardous waste incineration. Risk assessments
evaluate the relationship between exposure to toxic substances and the
subsequent occurrence of health' effects.
rotary kiln incinerator:
combustion chamber.
A type of [incinerator that includes a rotating
The constant rotation of the combustion chamber
keeps waste moving, allowing the wastes to vaporize (convert to gas)
for easier burning. , -.
secondary combustion chamber: The compartment or chamber immediately
following the primary combustion chamber. Organic compounds partially
combusted in the primary chamber are further combusted in the secondary
combustion chamber. ,
I
sludge: A thick, heavy, mud-like mixture of solids and liquids often
resulting from the settling of (solids from a liquid.
I
slurry: A thin, watery mixture of solids and liquids. Slurries contain more
water than sludges and, as a result, slurries flow more easily.
spray tower scrubber: A device that uses alkaline water to neutralize
hydrogen chloride gas. The alkaline water is injected in a spray of tiny
droplets into a chamber where tihe acid gas is also introduced. The small
size of the droplets aids in the neutralization of the gas.
supercritical vater: A type of thermal treatment that uses moderate
temperatures (>374°C) and high pressures to enhance the ability of
water to break down large organic molecules into smaller, less toxic
ones. Oxygen injected during this process combines with the simple
organic compounds to form carbon dioxide and water.
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Superfund: The Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA), passed in 1980. A federal statute that gives
the federal government the ability to respond to hazardous waste
releases that pose a potential threat to human health and the
environment. CERCLA established a fund (also known as "Superfund")
which finances the responses taken by the government.
thermal treatment:: The use of elevated temperatures to treat hazardous
wastes. Thermal treatment changes the chemical and/or physical composition
of a waste. Types of thermal treatment include incineration and pyrolysis.
trial burn: A test for incinerators in which wastes are fed into the
incinerator and emissions are monitored for the presence of specific
organic compounds (POHCs), particulates, and hydrogen chloride.
TSCA: Toxic Substances Control Act. The federal statute under which the
incineration of PCBs is regulated.
venturi scrubbers: Air pollution control devices that use water to remove
particulate matter from emissions. ,
waste feed:
from
The flow of wastes into an incinerator. Waste feeds can vary
continuous flows to intermittent (batch) flows.
waste minimization: Measures or techniques that reduce the amount of wastes
generated during industrial production processes.
100-year floodplain: The land area in the vicinity of a body of water that is
expected to be flooded once every 100 years. Determinations about the
location of a floodplain are made based on land areas affected by previous
floods and the frequency with which various size floods occur.
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