Website download address

1
Website download address

• Air Pollution
• http//www.public.iastate.edu/sung/ce326/air.ppt
  
• Solid Waste Management
• http//www.public.iastate.edu/sung/ce326/msw.p
  pt
• Hazardous Waste Management
• http//www.public.iastate.edu/sung/ce326/hwm.p
  pt

2

• Scope of Hazardous Waste (HW) Problem
• 1985 EPA Survey 2,959 facilities managing 247
  mil. tons of HW
• Chemical Manufacturers surveyed 681 industrial
  plants 213 mil. Tons (approx. Assoc. (CMA)
  1985 48 - 68 of total HW generation)
• Congressional Budget 223 308 mil. Tons
  
  Office (1982)
• Office of Technology 255 275 mil. Tons
  
  Assessment
• EPA National Biennial 20,233 generators and 3078
  Treatment, Storage or Hazardous Waste Disposal
  Facilities (TSDFs)
  Report 60 TSDFs managed 93 of HW

3

• Breakdown of the major HW are as follows
• 51 Chemical Products
• 7 Transportation Equipment
• 9 Petroleum and Coal Products
• 9 Electronics
• 8 Primary Metals
• 16 All other industries

4

• Overview of Hazardous Waste Management
• General definition of hazardous
• Potentially dangerous or harmful to human health
  or environment
• Capable of causing adverse physiological effects
• Statutes that primary address hazardous wastes
  are the Resource Conservation and Recovery Act
  (RCRA) and the Comprehensive Environmental
  Response, Compensation and Liability Act
  (CERCLA).
• RCRA is focused on the existing, active and
  future hazardous waste sites and management
• CERCLA is focused on inactive hazardous waste
  disposal sites (Superfund)

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• General Description of CERCLA
• The Comprehensive Environmental Response,
  Compensation and Liability Act (CERCLA) was
  enacted by Congress on Dec. 11, 1980. CERCLA is
  commonly known as Superfund. This law gives the
  Federal Government authority to respond to
• (a) Emergencies involving immediate and
  uncontrolled release of HW whether on land or in
  navigable waters
• (b) Identify uncontrolled and abandoned HW sites
  and ensure clean-up of the worst HW sites
• (c) Compel those responsible for the problem to
  clean-up the HW sites at their own expense or to
  recover the costs of federal actions

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• General Description of CERCLA (continued)
• CERCLA created a Hazardous Substances Release
  Trust Fund from taxes on the chemical and
  petroleum industries. Funds collected are used
  for the clean up of abandoned or controlled HW
  sites.
• CERCLA was amended in Oct 17, 1986 by the
  Superfund Amendments and Reauthorization Act
  (SARA). SARA significantly increase the size and
  scope of CERCLA program.
• CERCLA also established a priority list of
  abandoned or inactive HW sites for cleanup
  called the National Priority List (NPL)

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• RCRA Introduction and History
• Enact in 1976 to fill the regulatory pollution
  control gap between the Clean Air Act (1970) and
  the Clean Water Act (1972)
• Enacted as an amendment to the Solid Waste
  Disposal Act delegated US EPA the task of
  defining what substances are hazardous wastes
  and how these wastes should be regulated in order
  to prevent harm to human health or the
  environment
• In 1984, Congress amended RCRA through the
  Hazardous and Solid Waste Amendments (HSWA).
  Amendments were made in response to EPAs
  inability over the previous eight years to
  promulgate effective and satisfactory
  regulations. HSWA gave more specific guidelines
  for regulations, timetable for promulgation of
  regulations by installing minimum regulatory
  controls or hammers to promote rapid promulgation
  of regulations.
• Sections of RCRA that are important are Subtitle
  C of RCRA which establish a program to manage HW
  from cradle-to-grave and a program for
  identifying and listing HW

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• Identifying Hazardous Waste
• RARC Sec. 1004 (5) defines a hazardous waste as
• .. A solid waste, or a combination of solid
  wastes, which because of its quantity,
  concentration, or physical, chemical or
  infectious characteristics may (a) cause, or
  significantly contribute to an increase in
  mortality or increase in serious irreversible, or
  incapacitating reversible illness or (b) pose a
  substantial present or potential hazard to human
  health or the environment when improperly
  treated, stored, transported or disposed of or
  otherwise managed.
• By definition, all hazardous waste it must
  first be a solid waste. (Therefore, hazardous
  waste is a subset of solid wastes.)

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• Statutory definition of solid waste
• . Garbage, refuse, sludge from a waste
  treatment plant, water supply treatment plant, or
  air pollution control facility and discarded
  materials including solid, liquid, semi-solids or
  contained gaseous materials resulting from
  industrial, commercial, mining and agricultural
  operations, and from community activities but
  does not include solid or dissolved materials in
  domestic sewage, or irrigation return flows or
  industrial discharges which are point sources,
  special nuclear or by-product material as defined
  by the Atomic Energy Act of 1954.

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• A Solid Waste is a Discarded Material
• Under RCRA, a material must be discarded before
  it becomes a solid waste. RCRA was not intended
  to regulate raw materials or products, regardless
  of their hazardous characteristics, unless they
  have been discarded.
• The cradle-to-grave concept regulate the HW
  generators, transporters, and TSDFs and involves
  EPA, State and local regulatory agencies. The
  cradle-to-grave concept requires generators,
  transporters and TSDFs
• - to obtain an EPA Indentification Number
• - to use an uniform HW manifest that contains
  information on the generator, transporters, and
  TSDFs to track and manage HWs
• - to adopt DOT regulations for proper packaging
  and identification of HW during shipment
• - to provide guidelines for the safe disposal of
  HW by TSDFs

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HW Manifest
12
TSDFs

• Treatment, Storage or Disposal Facilities (TSDFs)
  include
• landfills,
• above ground tank systems,
• surface impoundments,
• waste piles,
• land treatment,
• incinerators,
• other thermal treatment units,
• chemical, physical and biological treatment units
  and
• underground injection wells.

13
Cradle-to-Grave Concept - Manifest System
Transporters
TSDFs
Generators
EPA
State
14

• When is a Solid Waste a Hazardous Waste
• A waste may be classified as a hazardous waste if
  the waste meets the criteria for any of the
  following categories
• Listed Waste
• F, K, P or U wastes
• 2. Characteristics Wastes
• Ignitability, Corrosivity, Reactivity, or
  Toxicity
• Mixed Wastes and Derived From Rules (not
  discuss in this class)

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• Listed Hazardous Wastes
• US EPA idenfied specific solid wastes that are
  hazardous wastes because of known hazardous
  characteristics. These lists consist of
• F Waste (40 CFR 261.32) manufacturing wastes
  from nonspecific sources, eg., spent solvents,
  electroplating wastes, wood preserving wastes
  (tetrachloroethylene, trichloroethylene)
• K Waste (40 CFR 261.32) manufacturing wastes from
  specific industrial processes, eg., wastes from
  wood preserving and petroleum refining industries
  (eg., distillation bottoms from production of
  acetaldehyde from ethylene)
• P Waste (40 CFR 261.33(3)) discarded chemical
  products or intermediates that are acutely toxic
  wastes
• U Waste (40 CFR 261.33(f)) discarded chemical
  products or intermediates that present risks of
  chronic toxicity from exposure
• P and U wastes contain specific chemicals such as
  organics, pesticides and acids (eg., acetone,
  aldicarb)

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• 2. Characteristic Wastes
• Waste may be regulated for exhibiting one of the
  following characteristics of a hazardous waste as
  determined by the EPA
• Ignitability
• Liquid except aqueous solutions containing less
  than 24 alcohol, that has flash point less than
  60oC
• Nonliquid capable, under normal conditions of
  spontaneous and sustained combustion
• Ignitable compressed gas under DOT regulations
• Oxidizer under DOT regulations
• Corrosivity
• Aqueous material with pH less than or equal to 2
  or greater than or equal to 12.5
• A liquid that corrodes steel at a rate greater or
  equal than ¼ inch per year at a temperature of
  55oC

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• Characteristic Wastes (continued)
• Reactivity
• Normally unstable and readily undergoes violent
  change without detonating
• Forms potentially explosive mixtures with water
• When mixed with water, it generates toxic gases,
  vapors, or fumes in a quantity sufficient to
  present a danger to human health or the
  environment.
• It is a cyanide or sulfide bearing waste which
  exposed to pH conditions between 2 and 12.5 can
  generate toxic gases, vapors or fumes in a
  quantity sufficient to present a danger to human
  health or the environment.
• It is capable of detonation or explosive reaction
  if subjected to a strong initiating source or if
  heated under confinement.
• It is readily capable of detonation or explosive
  decomposition or reaction standard temperature
  and pressure
• It is a forbidden explosive as defined in DOT
  regulations

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• Characteristic Wastes (continued)
• Toxicity
• Using an approved extraction method Toxicity
  Characteristics Leaching Procedure (TCLP), the
  extract from the waste contains any of the
  contaminants with a concentration equal to or
  greater than the values listed in the Table 10-10
  (see Text page 841)
• TCLP test procedures
• Solid material crush to particle size lt 9.5 mm
• Weak acetic acid addition acid solid 20 1
  by wt.
• 18 hrs 30 rpm at 22oC

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Table 10-10 p841 Toxicity characteristic constitue
nts and regulatory levels
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• Treatment Technologies for Hazardous Wastes
• Biological treatment, eg., use of conventional
  biological treatment processes such as activated
  sludge system and trickling filters to treat
  hazardous organic compounds
• Chemical Treatment for detoxifying HW include
  neutralization using acid or bases oxidation
  using chlorine, hydrogen peroxide and ozone and
  chemical precipitation adsorption using granular
  activated carbon or ion exchange resin and
  stabilization/solidification
• Physical Treatment separation or concentration
  of HW using distillation, filtration, membrane
  processes such as reverse osmosis
• Thermal Processes destruction of waste by high
  temperature, eg., incineration
• Land Disposal such as deep well injection,
  landfills, and surface impoundments

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Minimum requirement for a Secure Landfill design
Page 891
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• Destruction Removal Efficiency (DRE)
• DRE of 49s means 99.99

Example An initial concentration of contaminant
is 100 mg/L The concentration after treatment is
0.1 mg/L DRE (100 0.1)/100 0.999
99.9 gt 39s or 3 log reduction
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polychlorinated biphenyl (PCB)

• over 200 isomers
• different chlorine composition (Araclor 1248)
• virtually indestructible - useful as transformer
  fluid (in every transformer 1930 - 1970)
• toxic effects to exposed workers noted in 1937
• environmental contamination realized in 1969

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dioxin
o

• dibenzo - ? - dioxin
• over twenty different isomers
• byproduct of herbicide/pesticide manufacture
• created during incineration of hazardous wastes
• contaminant in 2,4-D, agent orange and others
• carcinogenic, teratogenic, mutagenic,
  embryo-toxic in animal studies
• bioaccumulates in fatty tissue
• no known link to human effects

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Calculating Cancer Risk for Carcinogen
Where TR Target cancer risk (dimensionless) Cw
Concentration of chemical of concern in water
(mg/L) IR Ingestion rate of water (L/day) EF
Exposure frequency (days/yr) ED Exposure
duration (yr) BW Body weight (Kg) ATc
Averaging time (life expectancy) for cancer
(days) SF0 Oral cancer slope factor (Kgday/mg)
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Slope Factor
Dose response curve
Risk, dimensionless
x
x
x
x
x
x
x
x
x
x
Slope at response of 1x10-6 Slope factor
(Kgday/mg)
1x10-6
Dose, mg/Kgday
EPA accept Linearized multistage extrapolation
method to estimate SF
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• Generally, lifetime cancer risk is calculated by
  assuming EF x ED ATc
• This simplifies the equation to

Some Oral Slope Factor Chemical SF0
(Kgday/mg) Arsenic (inorganic)
1.7500 Benzene 0.0290 Chloroform
0.0061 Hexachlorobenzene
1.6000 Hydrazine 3.0000
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Example Problem 1 Determine the lifetime risk
of cancer from drinking well water contaminated
with 0.5 mg/L benzene for five years. Assume IR
2.0 L/day BW 70 Kg ATc (70365)
25,550 days
About 1 in 100,000
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Example Problem 2 Determine the lifetime risk
of cancer from drinking a water source that
contains the MCL for benzene.
MCL maximum contaminated level MCL for benzene
0.005 mg/L (Text page 218 Table 4-7)
About 1 in 1,000,000
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• Flash Point The temperature at which a liquid or
  volatile solid gives off vapor sufficient to form
  an ignitable mixture with air

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• Chemical Precipitation for Heavy Metals Removal
• Example
• What is the minimum pH to have a Ca(OH)2 solution
  with Cu2 ion conc. lt 0.5 mg/L?

Ksp 2 x 10 -19 0.5 mg/L / (1000 mg/g x 63.54
g/mole) x OH-2 OH- 1.59 x 10-7 Kw H
OH- 1 x 10-14 Therefore H 10-14 / 1.59
x 10-7 6.28 x 10-8 gt pH -log H 7.2
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