27679
WLB:TDI1:01
LISTING BACKGROUND DOCUMENT FOR
DINITROTOLUENE, TOLUENEDIAMINE AND
TOLUENE DIISOCYANATE PRODUCTION1
Kill: Product washwaters from the production of dinitrotoluene
via nitration of toluene (C,T)
K112: Reaction by-product water from the drying column in
the production of toluenediamine via hydroyenation uf
dinitrotoluene (T)
K113: Light ends from the purification of toluenediamine
in the production of toluenediamine via hydrogenation
of dinitrotoluene (T)
K114: Vicinals from the
in the production
of dinitrotoluene
purification of toluenediamine
of toluenediamine via hydrogenation
(T)
K115: Heavy ends from the purification of toluenediamine
in the production of toluenediamine via hydrogenation
of dinitrotoluene (T)
K116: Organic condensate from the solvent recovery column in
the production of toluene diisocyanate via phosgenation
of toluenediamine (T)
-One waste from TDI production (EPA Hazardous Waste No. K027,
Centrifuge and distillation residues from toluene diisocyanate
production) was previously listed. A background document for
this listing has been available in the public docket at EPA
Headquarters and at EPA regional libraries since May 19, 1980.
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TABLE OF CONTENTS
PAGE
I. Summary of Basis for Listing 1
II. Sources of the Wastes 2
A. Profile of the Industry 2
B. Manufacturing Processes 4
1. Nitration of toluene to form dinitrotoluene (DNT) 5
2. Hydrogenation of DNT to form toluenediamine (TDA) 8
3. Formation of toluene diisocyanate (TDI) from TDA 12
III. Composition of the Wastes 16
IV. Waste Management 22
V. Basis for Listing 27
A. Hazards Posed by the Wastes 27
B. Degree of Hazards Posed by These Wastes 34
C. Mismanagement 37
D. Environmental Effects of the Hazardous Constituents 40
E. Health Effects of the Hazardous Constituents 43
VI. References 51
VII. Appendix I 52
VIII. Appendix II 53
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I. Summary of Basis for Listing
The above-listed solid wastes resulting from the nitration
of toluene to produce dinitrotoluene (DNT), from the hydrogenation of
DNT to toluenediamine (IDA)/ and from the reaction of IDA with phosgene
to form toluene diisocyanate (TDI), are hazardous solid wastes.
ft,^rft.-fiOn of "toluCnC
Administrator has determined that wastes from the a-bove—§>i=-e>ee-s«es
pose a substantial present or potential hazard to human health or
the environment when improperly transported, stored, disposed of
or otherwise managed, and therefore should be subject to appropriate
management requirements under Subtitle C of RCRA.JThis conclusion
is based on the following considerations:
1) Wastes from the production of dinitrotoluene, toluene-
diamine, and toluene diisocyanate typically contain
significant concentrations of one or more of the toxic
compounds: 2 ,4-dinitrotoluene, 2,6-dinitrotoluene, 2,4-
toluenediamine, 2,6-toluenediamine, 3,4-toluenediamine,
2-amino-l-methylbenzene (o-toluidine) , 4-amino-l-methyl-
benzene (p_-toluidine) , aniline, carbon tetrachloride,
tetrachloroethylene, chloroform, and phosgene.
2) A number of these compounds — namely, 2,4-dinitrotoluene,
2,4-toluenediamine, o-toluidine, chloroform, carbon tetra-
chloride, and tetrachloroethylene — have been identified
by the Agency's Carcinogen Assessment Group (CAG) as known
or potential carcinogens. In addition, several of these
compounds have been shown to be mutagens in bacterial or
mammalian test systems, and cause reproductive, terato-
genic, or otherwise chronic systemic effects.
3) Dinitrotoluene product washwaters (waste Kill) are also
corrosive (pH = 1 - 2), due to the high concentrations of
sulfuric and nitric acids.
4) These wastes are produced in large amounts: an approximate
total of 647,000 kkg of DNT, TDA, and TDI production wastes
are generated annually.
5) These toxicants, moreover, are mobile and persistent in the
environment. In fact, a number of these toxicants have been
found in drinking water or surface water, as well as in air,
and, thus, have been shown to leach and be sufficiently
persistent to escape into the environment and present a
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substantial hazard to human health or the environment,
if improperly managed, such as disposal in unlined surface
impoundments, or inadequate incineration.
II. Sources of the Wastes^
A. Profile of the Industry
The manufacture of toluene diisocyanate (TDI) from toluene
involves the production of dinitrotoluene (DNT) and toluenediamine
(IDA) as intermediates. As of 1983, five domestic companies were
producing TDI at seven locations (see Table 1).
Two other major manufacturers produce DNT and/or TDA
primarily for sale to TDI manufacturers. The Air Products plant
at Pasadena, TX is a key supplier of DNT and TDA, while the duPont
plant at Deepwater, NJ is also a major producer of DNT. There are
several other producers of DNT and TDA; however, their production
levels may be quite low, and some are producing TDA for captive use
in the manufacture of dyes or other chemical products. (Table 4,
which later discusses quantity and management data for the waste
streams of concern, includes not only data based upon the production
volumes of the DNT and TDA produced for captive use in TDI production,
but also includes the production volumes of the DNT and TDA produced
for sale to other facilities as intermediates in TDI production.)
TDI production capacity in the U.S. was 315,000 kkg in
1983. The U.S. International Trade Commission reported the total
production of TDI (80:20 mixture of the 2,4- and 2,6- isomers)
2The information presented in this section is taken in large part
from a 1983 report prepared by S-Cubed.
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TABLE 1 - PRODUCERS OF TOLUENE UIISOCYANATE {TDI}1
PRODUCER
Mobay Chemical Corp.
Bay town, TX
Mobay Chemical Corp.
New Mart insville, WV
ol in Corp.
Lake Charles, LA
Olin Corp.
Moundsville, WV
BASF Wyandotte Corp.
Geismar, LA
Dow Chemical
Freeport, TX
Rubicon Chemicals
Geismar, LA
TOTAL
RAW
MATERIAL
toluene
toluene
dinitro-
toluene
toluene
dinitro-
toluene
toluene
diamine
toluene
PRODUCTS2
1,2,3
1,2,3
2
2
2
2
2
CAPACITY3
(106 kg/yr)
59
57
45
34
57
4b
18
315
manufacturers of TDI are listed within this table. Other
manufacturers produce DNT and/or TDA intermediates but do not
produce TDI (see text).
2Key to Products:
1 = pure 2,4-TDI
2 = 80:20 mixture of 2,4- and 2,6-TDI
3 = 65:35 mixture of 2,4- and 2,6-TDI
3Nameplate capacity for TDI production as of 1983 (SRI International,
1983 Directory of Chemical Producers - United States, Stanford
Research Institute, Menlo Park, CA, 1983).
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domestically in 1980, 1981, and 1982. Reported production data
for DNT and IDA were less specific. However, based upon reaction
stoichiometry and estimates of process yields from process residuals
reported by manufacturers, it was possible to estimate the amounts
of DNT and IDA (as the 80:20 mixture of the 2,4- and 2,6- isomers)
produced in association with these levels of TDI in 1980, 1981,
and 1982. In particular, the production estimates are:
PRODUCTION ESTIMATES (in kkg)
1980 1981 1982
DNT 344,000 346,000 337,000
TDA 215,000 216,000 210,000
TDI 267,000 268,000 261,000
Five of the seven TDI-manufacturing plants produce only an 80:20
mixture of 2,4-TDI and 2,6-TDI, while two plants produce an 80:20
mixture, a 65:35 mixture of 2,4-TDI and 2,6-TDI, as well as pure
2,4-TDI. Almost all TDI is used to make polyurethanes, including
polyurethane foam products (85% of production), coatings, elastomers,
and adhesives.
B. Manufacturing Processes
The manufacture of toluene diisocyanate typically involves
three distinct continuous chemical processes:
1. nitration of toluene to form dinitrotoluene (DNT);
2. hydrogenation of DNT to form toluenediamine (TDA); and
3. reaction of TDA with phosgene to form TDI.
As shown in Table 1, four TDI plants begin the production process
with toluene and incorporate all three of these steps, two plants
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purchase DNT for use as a raw material, and one purchases TDA for
use as a raw material. The Air Products plant at Pasadena, TX,
with a reported annual capacity for TDA of 57,000 kkg, is a key
supplier of TDA, as well as DNT. The duPont plant at Deepwater,
NJ, is also a major producer of DNT.
The following is a description of the major commercial
processes utilized in the manufacture of DNT, TDA, and TDI.
1. Nitration of toluene to form dinitrotoluene (DNT)
In general, toluene is nitrated with nitric acid in the
presence of sulfuric acid, which acts as a solvent and a catalyst
Increasing the acidity and temperature increases the degree of
nitration. The dinitration of toluene is represented by the
overall reaction:
CH3 CH3
. 2HN03
M i t T i r
Toluene Ir-fd Dinitrotoluene
C a (DNT)
As shown in Figure 1, sulfuric and nitric acids are
added to a recycled acid stream to form the nitrating solution.
This solution is combined with toluene in the nitration reactor.
The reactor is jacketed, and continuously cooled to remove the
heat of reaction. The reactor contents must be vigorously agitated
because toluene is not very soluble in the mixed acids. Most
TDI manufacturers use either nitration-grade toluene (99.8%
purity) or highly refined toluene (99.5+% purity) as a feedstock.
The two-phase product from the nitration reactor is
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Vent Gas
Wflshwater
Kill
Acid Recovery Water
ONT
Product
r-'iqure 1. Typical Process Flow niar\rf\m for UKJ Nitration ot Toluene
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allowed to separate into organic and acid layers. Spent acid
from the acid separation unit is sent to a recovery unit where
water (a by-product of the nitration reaction) is separated and
re-used in the washing process. The recovered acid solution is
reconstituted into a nitrating solution containing the desired
concentrations of sulfuric and nitric acids. After addition of
make-up sulfuric and nitric acids, the nitrating acid solution
consists of about 50% sulfuric acid, 20% nitric acid, 12% nitro-
sylsulfuric acid, and 8% nitroorganics.
The organic layer contains the desired dinitrotoluenes,
as well as side products of reaction, and is subjected to purifica-
tion. A two- or three-stage washing process is typically employed
to remove water-soluble organic by-products and any remaining spent
acid from the crude DNT product stream. The first washing step
utilizes an alkaline wash solution containing sodium hydroxide,
ammonium hydroxide, or sodium carbonate to remove acidic by-products.
Water from the acid recovery unit is usually combined with additional
water, if necessary, and is then re-used in the remaining washing
steps. Washwaters from the washing process are combined and form
a major waste from the toluene nitration process (Kill in Figure 1).
Vent gases from the nitration reactor and other units may
be scrubbed with water to remove acid fumes. Scrubber waters, if
generated, are typically utilized subsequently for product washing.
The dinitrotoluene (DNT) product consists of about 96% 2,4-
and 2,6-DNT, and 4% of other isomers, primarily 2,3- and 3,4-DNT (see
Figure 2). Operating conditions are controlled so as to reduce the
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formation of trinitrotoluene. Several oxidized by-products, including
nitrocresols, nitrophenols, and nitrobenzoic acids, also result,
however. These may constitute up to 2% of the product mixture.
2. Hydrogenation of DNT to form toluenediamine (TDA)
The reduction of DNT to TDA occurs in liquid (often
methanolic) phase hydrogenation at high temperature and pressure,
and occurs according to the following reaction:
CH3
(N02)2 + 8H2 Catalyst. [Gj—(NH2)2
Dlnitrotoluene Toluene Oianrine
(DNT) (TDA)
Hydrogenation is not specific, and results in the reduction
of any nitroaromatic compound to the corresponding amine (occurring
without rearrangements). For this reason, the isomeric distribution of
the TDA product is iaentical to that of the DNT used as a raw material.
The crude diamine product may contain partially reduced
compounds (nitroamino toluenes), and small amounts of cyclohexane
derivatives that result from aromatic ring hydrogenation. Hydrogen-
ation proceeds through the intermediate formation of nitroso (R-NO)
and hydroxylaraine (R-NH-OH) intermediates. In addition, polymeric
condensation species of azo (R-N=N-R) or hydrazo (R-NH-NH-R) linkages
may be formed. A flow diagram for a typical hydrogenation process
is shown in Figure 3.
The DNT feed is dissolved in solvent, typically methanol,
combined with the catalyst (either palladium on carbon or Raney
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2,5-ONT
0.5%
2.4-DNT
77%
2,67DNT
19*
3,4-DNT
2,3-DNT
1.0%
Figure 2. Isomer Protluction in the Nitration of Toluene
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By-Product
i Water
K1I2
u)
I iyht
Umls
K113
Vicinals
K114
Make-Up
Solvent
DNT-
Recycled
Solvent
Catalyst
M2-
Reactor
Catalyst
Recovery
Recycled
Spent
Catalyst
Catalyst
IDA
Product
c
E
fO
t-
nt
OL
01
to
a*
T
Heavy Cnds
K115
Fifjnr/e 3. Typical Process Flow Diagram for the Hyrirogenat ion of" DNT to TIJA
-------
nickel), and sent to a pressurized reactor, where hydrogen is
introduced. The operating temperature of the reactor is between
90 and 190°C at a pressure of about 6 atmospheres. The output from
the reactor is sent to a catalyst recovery unit where recovery is
accomplished by centrifugation, filtration, or settling, and the
recovered catalyst is sent back to the reactor. Small amounts of
the catalyst may be lost as fines in the crude product stream or
intentionally discarded as a portion of the recovered catalyst
stream. New catalyst is then added so as to retain catalyst activity.
The crude TDA product then goes through a series of distill-
ation columns to remove the following components:
1. solvent (generally methanol) from the solvent recovery
column, which is recycled;
2. by-product water (K112, resulting from the hydrogenation
reaction) from the TDA drying column;
3. light ends (K113) from the light ends separation column;
4. vicinals (process residuals resulting from the separation
of the ortho isomers from the desired product isomers)
(K114) from the vicinals separation column; and
5. heavy ends (K115) from the residue separation column.
As illustrated in Figure 3, by-product water is the second distill-
ation product (K112). It contains toluenediamines and toluidines,
as well as methylcyclohexanes and small amounts of methanol.
Low-boiling by-products, or light ends (K113), are typically
separated in a third distillation column as a gaseous overhead stream.
Although these wastes come off the distillation column as gases because
of the high temperatures employed in distillation, they quickly condense
to liquids (their natural state) on contact with the surrounding lower
temperatures. This stream contains primarily toluenediamines and
toluidines, but also contains aniline and water.
11
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The fourth distillation column separates out the
toluenediaraines with ortho amine groups (vicinals), which boil
at slightly lower temperatures (2,3-TDA boiling point = 255°C;
3,4-TDA boiling point = 265°C) than the desired product amines
(2,4-TDA boiling point = 292°C; 2,6-TDA boiling point = 292°C)
(K114 of Figure 3). If not separated from the TDA product stream,
the ortho (2,3- and 3,4-) diamines form cyclic ureas in the
subsequent phosgenation reaction (see below), resulting in
reduceu product yield, and increased amounts of "heavy ends"
residue from the TDI purification process.
The residue separation column is the final distillation
step, and the "heavy ends" (K115 of Figure 3) are removed at this
point. The heavy ends consist primarily of toluenediamines.
3. Formation of toluene diisocyanate (TDI) from TDA
TDI results from the reaction of TDA with phosgene:
CH3
(NH2)2 + 2COC12
Toluene Phosgene Toluene
Diamine Diisocyanate
trn A\ (TDI}
^ ' >»" /
This reaction proceeds at atmospheric pressure and without a
catalyst. A typical process flow diagram is shown in Figure 4.
It is necessary to use TDA of high isomeric purity to
reduce side reactions. 2,3- and 3,4-TDA form methylbenzimidazolone
in preference to the diisocyanate, reducing the reaction yield:
12
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Vent Gas
Vent.Gas
Water
HC1 Solutl m
(Coproduct)
T
Phosyene
Recycle
Organic
Liquid
K116
(condonscice)
Phosyene
So1utior
Phosgene
Product TOI
fa
c
O
n>
O
i
-------
2HC1
H
"faluene-2, Phosgene Cyclic Urea
3-Qi ami ne (Methyl-benzimi dazolone}
In addition, the imidazolone combines with TDI, forming intractable
sludges, which present physical removal problems. Therefore, the
IDA feed to this process is usually of very high isomeric purity;
it consists of an 80:20 (+_ 11) mixture of the 2,4- and 2,6-isomers.
The TDA is dissolved in chlorobenzene, o-dichlorobenzene,
or other solvents. This solution is combined with phosgene (either
in solution with the same solvent or as a liquid) in phosgenation
reactors. The phosgene feed may contain low molecular weight
chlorinated hydrocarbons (primarily carbon tetrachloride) impurities.
Phosgenation is accomplished in a series of phosgenators,
with increasing temperatures in each successive phosgenator. Phosgene
liquid is fed into the bottom of the phosgenators. Phosgenator vent
gases are typically sent through a condenser, the condensate returned
to the phosgenator, and uncondensed gases sent to a phosgene and HC1
by-product recovery system.
The crude TDI product that exits from the phosgenation
reactors undergoes stepwise distillation to separate the following
components:
1. phosgene, from the phosgene recovery column, which
is recycled to the phosgenation reactors;
2. by-product HCl from the scrubber system;
3. solvent, from the solvent recovery column, recycled
to the phosgenators;
14
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4. organic liquid (condensate) containing chlorinated
hydrocarbon impurities and excess phosgene (K116), from
the solvent recovery and subsequent separation columns;
5. TDI residue (K027, currently regulated in CFR 261.32),
the heavy ends from the residue separation column; and
6. purified TDI product.
Figure 4 provides a representative process flow diagram for separa-
tion of these components (the seven TDI plants surveyed demonstrated
slightly different processes).
In the process shown in Figure 4, phosgene and by-product
HCl are distilled from the product stream at relatively low tempera-
tures, combined with vent gases from the phosgenation reactors, and
fed to the phosgene/HCl recovery section, where phosgene is absorbed
in the process solvent, and HCl is subsequently absorbed in water.
The phosgene/solvent solution is then stripped of phosgene with
a gas, and the phosgene is condensed out of this gas stream and
recycled to the phosgenators. Vent gases that have been stripped
of phosgene are commonly sent to a final scrubber for HCl recovery.
These gases are scrubbed with water or a caustic solution to
remove the remaining traces of phosgene. Carbon adsorption is
also employed to remove trace chlorinated organics from vent
gases. HCl may be utilized in other processes within the plant,
or marketed.
After separation of phosgene and HCl from the crude
product stream, a second distillation step is carried out for
recovery of the process solvent as an overhead stream from the
solvent recovery column. Further distillation of this stream may
be needed to separate a liquid containing chlorinated hydrocarbon
impurities and excess phosgene originally associated with the
15
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phosgene feed, from the solvent. The resulting condensate (K116
in Figure 4) therefore contains chlorinated hydrocarbons, phosgene,
and some residues of the solvent used in the process.
The final separation removes the TDI product from the
higher-boiling distillation bottoms (the currently regulated waste,
K027). As discussed above, these still bottoms are expected to
contain polymeric condensation by-products, TDA, and TDI.
The TDI product (80:20 mixture of 2,4- and 2,6-isomers)
may be subjected to further distillation steps to produce both a
pure 2,4-TDI product and a 65:35 mixture of the 2,4- and 2,6-
isomers, but these distillations do not produce wastes.
III. Composition of the Wastes3
The nitration of toluene creates one major waste stream,
the product washwaters from washing the crude DNT product (Kill).
Because of the relatively high concentrations of sulfuric and
nitric acias {ranging from 1 - 4%), this waste stream also is
corrosive, due to its pH of between 1-2. In addition, this
waste stream is toxic; the hazardous constituents, as determined
from RCRA Section 3007 questionnaires and sampling and analysis,
are expected to be dinitrotoluenes (about 0.1%), of which 0.08%
of the waste is 2,4-DNT, and 0.02% is 2,6-DNT. in addition,
this waste is expected to contain dinitrocresols (about 0.06%,
primarily 2 ,6-dinitro-p_-cresol); mononitrotoluenes (about 0.005%);
and mononitrophenols, dinitrophenols, nitrobenzoic acids, and
3see footnote 2.
16
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mononitrocresols (about 0.007%, combined).4 (See Tables 2 and 3.)
A second major aqueous waste is the reaction by-product
water from the hydrogenation of DNT to TDA (K112). This waste
contains a substantial concentration of 2,4- and 2,6-TDA (ranging
from 0.05 - 0.3%), 3,4-TDA (ranging from 0.05 - 0.3%), as well as
£-toluidine (ranging from 0 - 0.06%) and £-toluidine (ranging from
0 - 0.04%), which are the hazardous constituents of concern. In
addition, one manufacturer reported methylcyclohexylamine and
methylcyclohexanone as components of this waste stream.4
Purification of the crude TDA product by distillation
produces "light ends", "vicinals", and a "heavy ends" waste stream.
The light ends (K113) typically consist of 3,4-TDA (ranging from
0 - 37.5%) and 2,4- and 2,6-TDA (ranging from 0 - 37.5%); o-toluidine
(ranging from 0.6 - 6%) and £-toluidine (ranging from 0.4 - 4%);
and aniline (ranging from 0.01 - 0.1%), the hazardous constituents
of concern.
The hazardous constituents from the vicinals waste
stream from the purification of crude TDA (K114) are 2,4- and
2,6-TDA (ranging from 4.5 - 50%); 3,4-TDA (ranging from 45 -
95%); o-toluidine (ranging from 0-3%) and p_-toluidine (ranging
from 0 - 2%).
2,4- and 2,6-TDA (ranging from 10 - 50%), and 3,4-TDA
4We are not proposing to list these additional compounds as hazardous
constituents at this time since we currently have insufficient data
on concentrations and/or toxicity to justify such listing; however,
in the future, if we do receive more information on them, we will
then make a determination as to whether or not they should be listed
17
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TABLE 2: APPROXIMATE AVERAGE COMPOSITION OF DNT WASHWATER1
Constituent
Dinitrotoluenes
(see Figure 2 for approximate
isomer distribution)
Mononitrotoluenes
(see Figure 2 for approximate
isomer distribution)
Dinitrocresols
(mostly 2,6-dinitro-p_-cresol)
Nitrophenols
(including di- and mono-nitrophenols)
Other nitroaromatics, including
nitrobenzoic acids and nitrocresols
TOTAL ORGANICS
Concentration (ppm)
1U85
45
600
35
35
1800
T-S-CUBED, 1983
18
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J: COMPOSITION OF MAJOR WASTE STREAMS FHDM PLANTS THAT MANUFACTURE DNT, TDA & TDI
WASTE STREAM
DESIGNATION
Kill
K112
K113
K114
K115
K116
K0272
!
DESCRIPTION
(Figs. 1,3,4)
DNT Washwater
Byproduct water from
the TDA drying column
Light ends from the
purification of
crude TDA
Vicinals from the
purification of
crude TDA
Heavy ends from the
purification of
crude TDA
Organic liquid con-
taining chlorinated
hydrocarbon impurities
Heavy ends from the
purification of
crude TDI
TYPE
Aqueous
liquid
(pH=l-2)
Aqueous
liquid
Organic
liquid
Viscous
organic
liquid/
solid
Viscous
organic
liquid
Organic
liquid
Viscous
organic
liquid
MAJOR CONSTITUENTS
CONSTITUENT
Dinitrotoluenes ,
N i tr ophenol i cs
Inorganics^
H2S04 + HN03
Sulfate +
Nitrate Salts
Toluenediamines
2,4-TDA & 2,6-TDA
3,4-TDA (& 2,3-TDA)
Toluidines
o-toluidine
p_-toluidine
Toluenediamines
2,4-TDA & 2,6-TDA
3,4-TDA (& 2,3-TDA)
Toluidines
o-toluidine
pj-toluidine
Aniline
Toluenediamines
2,4-TDA & 2,6-TDA
3,4-TDA (& 2,3-TDA)
Toluidines
o-toluidine
p_-toluidine
To luened i ami nes
2,4-TDA & 2,6-TDA
3,4-TDA (& 2,3-TDA)
Spent Catalyst (Ni)
Carbon tetrachloride
Tetrachlorcethylene
Chloroform
Phosgene
Polymerized TDI
TDI
ESTIMATED
CONCENTRATION
RANGE (%)
0 - 0.3
1 - 4
0.1 - 0.6
0.05 - 0.3
0.05 - 0.3
0 - 0.1
0 - 0.06
0 - 0.04
0-75
0 - 37.5
0 - 37.5
1-10
0.6 - 6
0.4 - 4
0.01 - 0.1
0-95
4.5 - 50
45 - 95
0-5
0-3
0-2
10 - 50
10 - 50
0 - 2.5
0-5
0-75
0-15
0-7
0-30
50 - 100
0-50
^Inorganic composition varies between plants depending on the degree to which acids (H2SO4
+ HN03) in the crude DNT product are neutralized by alkaline washwaters.
2This waste is currently regulated in 40 CFR 261.32.
19
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(ranging from 0 - 2.5%), are the hazardous constituents of concern
of the TDA "heavy ends" (K115). In addition, TDA polymers and
other high-boiling residues, and small amounts of catalyst fines
(most commonly Raney nickel) are present.5 None of the TDI
manufacturers reported specific polymeric components; however,
the process chemistry indicates that the major polymerics are
toluenediamines of short length with azo (-N=N-) or hydrazo
(-NH-NH-) linkages.
The TDI purification processes additionally generate an
organic liquid waste stream (K116) of small volume but containing
10 - 30% phosgene, and chlorinated hydrocarbons, principally carbon
tetrachloride (ranging from 0 - 75%), as well as tetrachloroethylene
(ranging from 0 - 15%), and chloroform (ranging from 0 - 7%), as
the hazardous constituents. One manufacturer employs a vacuum
ejector which uses toluene as the motive fluid/ thus introducing
toluene (about 60%, with this system) into this waste.5
The final major waste from the production of TDI is the
"heavy ends" from purification of crude TDI. This waste stream
is currently regulated in 40 CFR 261.32 as "K027, Centrifuge and
distillation residues from toluene diisocyanate production". This
waste contains TDI, TDA, TDI polymers, and high-boiling by-products
from the phosgenation reaction. None of the TDl plants currently
operating reported specific component information on this waste.
However, one manufacturer (whose plant closed in 1981) reported
the following composition for this waste stream.
5see footnote 4.
20
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COMPONENT CONCENTRATION (%)
Isocyanurates (TDI triraer) 45
Carbodiimides 40
Ureas 10
Methyl-benzimidazolones 5
This appears to be a representative composition for an aged TDI
residue {one that has been stored for several days, resulting in
polymerization of the TDI monomer).6
Approximately 647,000 kkg of the TDI production wastes dis-
cussed above are generated annually. (This volume does not include
the approximately 21,000 kkg of the currently regulated EPA Hazardous
Waste No. K027, discussed above.) This volume is broken down by
waste stream as follows (total estimated generation, in kkg):
Kill - 427,000
K112 - 195,000
K113 - 240
K114 - 3,700
K115 - 21,000
K116 - 150
As seen above, a number of hazardous constituents are present in
high concentrations in the wastes. Therefore, if the wastes were
improperly managed, there is the potential that relatively large
amounts of these constituents could escape to the environment.
Table 3 is a summary of waste composition data for the wastes,
as supplied by the manufacturers and derived from the literature.
listing background document for EPA Hazardous Waste No. K027
estimated a slightly different composition for this waste.
21
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The potential environmental and human health effects of
these compounds are discussed in Section V.
In addition, there are a number of minor process waste
streams, including aqueous wastes from steam ejector systems for
vacuum distillation columns, scrubber wastewater, spent vacuum pump
oil, spent catalyst, and spent activated carbon from the treatment
of aqueous wastes or air emissions. These wastes are extremely varia-
ble in quantity and composition, depending on the process flow scheme
and unit operations utilized. They are not generated industry-wide
on a regular basis, and have not been fully characterized. There-
fore, we are not proposing to list these minor process waste streams
at this time; however, if in the future more information becomes
available, we will then make a determination on whether there is
sufficient justification for listing.
IV. Waste Management?
Table 4 presents a summary of management information con-
cerning these wastes. They are managed by a variety of techniques.
In most plants, DNT washwater (Kill) and TDA reaction
by-product water (K112) are treated by biological and/or physical-
chemical treatment, and then discharged to surface waters. At
least one manufacturer, however, uses a deep well injection
system for these wastewaters.
Although no information was specifically collected from
See footnote 2.
22
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TABLE 4: SUMMARY OF QUANTITY AND MANAGEMENT DATA FOR MAJOR WASTE STREAMS
FROM PLANTS THAT MANUFACTURE DOT, TDA & TDI
WASTE
DESIGNATION
Kill
K112
K113
K114
K115
K116
K0274
GENERATION RATE
(kg of waste/kg TDI
Produced)
1.1 - 2.0
0.44 - 1.23
0.004 - 0.012
0.012 - U.065
0.02 - 0.25
0.0003 - 0.007
0.09 - 0.28
TOTAL ESTIMATED
GENERATION1
(kkg/yr)
427,000
195,000
240
3,7UO
21,OOU
150
21,000
MANAGEMENT
SEQUENTIAL TECHNIQUES USED2
NTRL, BIOL, CRBN, DSWR
NTRL, CRBN, STLG, DSWR
SIMP, DWI
Unknown
NTRL, BIOL, CRBN, DSWR
BIOL (SIMP), DSWR
CTRT, CR8N, NTRL, DSWR
SIMP, DWI
Unknown
SIMP, DWI
INCN
Unknown
KCRY
MKTD
INCN-OFST
FUEL
Unknown
INCN
LDFL-OFST
Unknown
INCN
INCN
A***********************
PILE, LDFL-OFST
FUEL
PILE, LDFL
USE (%)3
60
11
4
25
27
29
19
4
21
71
8
21
23
21
18
17
21
76
3
21
100
35
********
18
12
1
^Total waste stream quantity generated in association with the production of TDI and
intermediates, based on 19 BO production figures.
to management techniques:
BIOL = Biological wastewater treatment CRBN = Carbon adsorption
CIRT = Chemical treatment DSWR = Discharge to surface waters
DWI = Deep well injection FUEL = Used as a fuel in a boiler or other device
INCN = Incineration LDFL = Landfill
MKTD = Marketed as a by-product NTRL = Neutralization
•OFST = Off-site unit process (all management techniques on-site unless specified otherwise)
PILE = Storage in a pile or a shed RCRY = Unspecified recovery of waste
*******CONFIDENTIAL BUSINESS INFORMATION
STLG = Settling SIMP = Surface impoundment
'^Percentage of total generated waste treated by the sequence of techniques indicated.
4This waste is currently regulated in 40 CFR 261.32.
23
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the two major manufacturers of DNT and TDA for non-captive use,
some general knowledge of their management techniques was available
from other sources. The duPont plant at Deepwater, NJ (manufacturer
of DNT only), utilizes their patented PACT® process for treatment of
combined washwaters, including the washwater and the acid recovery
wastewaters from their DNT production. This treatment process in-
volves neutralization with lime, primary clarification, combined
activated sludge/powdered activated carbon treatment, and discharge
to surface waters. Management techniques utilized at the Air Products
plant at Pasadena, TX (manufacturer of DNT and TDA) are not specifically
known, but may include a deep well injection system for aqueous wastes.
Wastes K113, K114, K115 result from product purification.
Waste K113, the light ends, may be combined with waste K112, if
mostly aqueous, for treatment and discharge to surface waters.
Some plants, however, separate this waste to include very little
water, and incinerate it. *************************************f
Waste K114, the vicinals, consists primarily of the ortho
(2,3- and 3,4-) toluenediamines, which have slightly lower boiling
points than the desired product (2,4- and 2,6-TDAs). Because of
this, the ortho TDAs can be recovered and marketed as a by-product.
However, it has also been reported to be used as a fuel or incinerated.
The TDA heavy ends (waste K115) are usually incinerated;
however, some landfilling is also practiced. (Three manufacturers
did not report its generation; they apparently allow high-boiling
* indicates that this is CONFIDENTIAL BUSINESS INFORMATION and is
in the record for this rulemaking.
24
-------
polymeric residue in the TDA product to continue on to the phosgenation
process, ultimately increasing the quantity of TDI heavy ends.)
The TDI purification processes additionally generate an
organic liquid waste stream (K116) of small volume but containing
phosgene and chlorinated hydrocarbons (and, in the case of one
manufacturer, toluene). Most facilities dispose of this residue
by incineration, either on-site or off-site.
Management of the TDI heavy ends (K027), currently regulated
in 40 CFR 261.32, varies, including both incineration and landfill.
One other plant reported utilization of this residue as a fuel but
provided no details.
In addition to these major waste streams, several minor
process waste streams were reported by TDI manufacturers. These
include aqueous wastes from steam ejector systems for vacuum
distillation columns, scrubber wastewater, spent vacuum pump oil,
spent catalyst, and spent activated carbon from the treatment of
aqueous wastes or air emissions. These wastes are extremely
variable in quantity and composition, depending on the process
flow scheme and unit operations utilized.
Aqueous waste streams are typically combined, sent to
biological and/or physical chemical wastewater treatment systems,
and then discharged to surface waters. Aqueous cleanup wastes
are probably sent to the same wastewater treatment facilities as
aqueous process wastes. Data regarding the use of impoundments in
25
-------
the treatment of aqueous wastes were reported by two manufacturers:
*******************************************************************
*************************************
Spent vacuum pump oil is typically very small in volume
and is incinerated.
Spent catalyst from the DNT hydrogenation process was
reported as a waste stream by only one manufacturer. However,
the literature and experience with similar processes suggest
•
that spent catalyst is frequently a waste stream in this process.
Raney nickel appears to be the most widely used catalyst although
the possible use of palladium on carbon is suggested in the
literature. Due to the inherent value of the metal components
in these catalysts, the spent catalyst is often reclaimed.
Very little information was supplied by the manufacturers
regarding spent activated carbon quantities and management.
However, economics often favor thermal regeneration of spent
activated carbon.
Some of the manufacturing products, if discarded for
any reason, including if the product is off-specification, are
currently regulated in 40 CFR 261.33(£): U105, 2,4-dinitrotoluene;
U106, 2,6-dinitrotoluene; U221, toluenediamine; and U223, toluene
diisocyanate. Section 261.33(f) only pertains to the discarded
commercial chemical products, manufacturing chemical intermediates,
or off-specification commercial chemical products, container residues,
and spill residues.
26
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V. Basis for Listing
A. Hazards Posed by the Wastes
1) Waste No. Killi Product washwaters from the production
of dinitrotoluene via nitration of toluene.
The nitration of toluene to produce dinitrotoluene requires
highly acidic conditions. Because of the high {up to 4%) concen-
tration of nitric and sulfuric acids, this waste is corrosive, with
a pH between 1-2. Therefore, this waste meets the corrosivity
characteristic (40 CFR 261.22) and is thus defined as hazardous.
In addition, this waste is expected to contain significant
concentrations of 2,4-dinitrotoluene, a mutagen as well as having
evidence of carcinogenicity, as determined by the Agency's Carcinogen
Assessment Group (GAG); and 2,6-dinitrotoluene, an experimental muta-
gen (i.e., positive in in_ vitro or other short term tests). {See
Section V.B. for discussion of toxic levels). Both are currently
listed as toxic constituents in Appendix VIII of 40 CFR 261.
As discussed above, a total of 427,000 kkg of waste Kill
is estimated to be generated per year, based on 1980 TDI production
figures, with 2,4-dinitrotoluene and 2,6-dinitrotoluene constituting
0.08% and 0.02%, respectively. Thus, approximately 342 kkg of
2,4-DNT and 85 kkg of 2,6-DNT could potentially escape into the
environment from this waste.
Although experimental environmental persistence data is not
currently available for dinitrotoluenes, they have been demonstrated
to be both sufficiently mobile to leach out of improperly disposed
27
-------
wastes, and sufficiently persistent to remain in the environment
long enough to cause substantial hazard, especially as a water
contamination problem. This conclusion is supported by the detection
of these toxic materials in United States tap water, ambient water
and finished effluent (see Sections V.C. and D.).
These factors, as well as the toxicity of these constitu-
ents (discussed in detail in section V.E.), contribute to the
potential hazards posed by this waste, justifying a hazardous
waste listing.
2) Waste No. K112, Reaction by-product water from the
drying column in the production of toluenediamine via hydrogenation
of dinitrotoluene.
This waste is expected to contain significant concentra-
tions of 2,4- and 2,6-toluenediamine (TDA) and 3,4-TDA, which are
currently listed (as toluenediamine) as toxic constituents in
Appendix VIII of Part 261, and o- and p_-toluidines, which we are
proposing to add to Appendix VIII. Of these compounds, 2,4-TDA
and o-toluidine have been determined by the Agency's CAG as having
evidence of carcinogenicity; 2,4-TDA is also reported to be mutagenic,
In addition, 2,6- and 3,4-TDA have been found to be experimental
mutagens; while p_-toluidine was found to cause chronic blood effects,
in addition to causing hepatomas in mice. (See Section V.B. for
discussion of toxic levels.)
A total of 195,000 kkg of this waste is estimated to be
generated annually, based on 1980 TDI production figures, with 2,4-
and 2,6-TDA constituting between 0.05 - 0.3%; 3,4-TDA ranging between
0.05 - 0.3%; and £- and p_-toluidine constituting between 0 - 0.06%
28
-------
and 0 - 0.04%, respectively. Thus, there is a potential for escape
of these constituents into the environment from waste K112 up to
the following amounts (based upon the higher concentration limit}:
2,4- and 2,6- TDA 585 kkg
3,4-TDA 585 kkg
o-toluidine 117 kkg
£-toluidine 78 kkg
Because of the high concentrations of these constituents,
and since wastewater treatment and surface impoundment are commonly
used management techniques, there is a high risk of their escaping
into the environment. Several of these constituents are both acute
and chronic toxicants (see Section V.E.), so a serious potential hazard
is presented by their release into the environment. These constitu-
ents, moreover, are all mobile in the environment (based on their
solubility in water and in other solvents), and some are expected to
be persistent (see Section V.D.); in addition, they are generated in
large quantities. Therefore, if improperly managed, they are likely
to enter into, and remain in the environment, posing substantial
risk. These considerations justify a hazardous waste listing.
3) Waste No. K113, Light ends from the purification of
toluenediamine in the production of toluenediamine via hydrogen-
ation of dinitrotoluene.
This waste is expected to contain significant concentrations
of 2,4-, 2,6-, and 3,4-TDA; o- and £-toluidine; and aniline. The
potential hazards of the TDAs and toluidines to human health and the
environment are outlined above. Aniline is carcinogenic in rats,
teratogenic, and chronically toxic. (See Section V.B. for discussion
of toxic levels.)
29
-------
A total of 240 kkg of this waste is estimated to be generated
annually, based on 1980 TDI production figures, with 2,4- and 2,6-TDA
constituting between 0 - 37.5%; 3,4-TDA ranging up to 37.5%; o- and
£-toluidine constituting between 0.6 - 6% and 0.4 - 4%, respectively;
and aniline constituting between 0.01 - 0.1%. Thus, there is a potential
for release of these constituents into the environment from waste K113
up to the following amounts (based upon the higher concentration limit):
2,4- and 2,6- IDA 90 kkg
3,4-TDA 90 kkg
o-toluidine 14 kkg
£-toluidine 10 kkg
aniline 0.24 kkg
Because of the high concentrations of these constituents,
and since surface impoundments are a commonly used management tech-
nique, there is a high risk of their escaping into the environment.
Several of these constituents are acute and/or chronic toxicants (see
Section V.E.), so a serious potential hazard is presented by their
release into the environment, should improper management occur. These
constituents, moreover, are all mobile in the environment (based on
their solubility in water and in other solvents), and some are expected
to be persistent (see Section V.D.). In addition, they are likely to
enter into, and remain in the1 environment, posing substantial risk.
These considerations justify a hazardous waste listing.
4) Waste No. K114, Vicinals from the purification of
toluenediamine in the production of toluenediamine via hydrogenation
of dinitrotoluene.
This waste is expected to contain significant concentra-
tions of 2,4-, 2,6-, and 3,4-TDA, and o- and p_-toluidine. (See
30
-------
Section V.B. for discussion of toxic levels.) The potential
hazards to human health and the environment of TDAs and toluidines
have already been discussed above.
A total of 3700 kkg of this waste is estimated to be
generated annually, based on 1980 TDI production figures, with 2,4-
and 2,6-TDA constituting between 4.5 - 50%; 3,4-TDA ranging up to
95%; and o_- and p_-toluidine constituting between 0-3% and 0-2%,
respectively. Thus, there is a potential for release of these
constituents into the environment from waste K114 up to the
following amounts (based upon the higher concentration limit):
2,4- and 2,6- TDA 1850 kkg
3,4-TDA 3515 kkg
o_-toluidine 111 kkg
£-toluidine 74 kkg
Because of the high concentrations of these constituents,
and since these constituents are all acute and/or chronic toxicants
(see Section V.E.), a serious potential hazard is presented by their
release into the environment. These constituents are all mobile in the
environment (based on their solubility in water and other solvents),
and some are expected to be persistent (see Section V.D.); in addition,
they are generated in large quantities. Therefore, they are likely to
enter into, and remain in the environment, posing substantial risk.
These considerations support a hazardous waste listing.
5) Waste No. K115, Heavy ends from the purification of
toluenediamine in the production of toluenediamine via hydrogenation
of dinitrotoluene.
This waste is expected to contain significant concentrations
31
-------
of 2,4-, 2,6-, and 3,4-TDA. (See Section V.B. for discussion of toxic
levels.) The potential hazards of TDA to human health and the
environment are outlined above.
A total of 21,000 kkg of this waste is estimated to be
generated annually, based on 1980 TDI production figures, with
2,4- and 2,6-TDA constituting between 10 - 50%; and 3,4-TDA
ranging up to 2.5%. Thus, there is a potential for release of
these constituents into the environment from waste K115 up to
the following amounts (based on the higher concentration limit):
2,4- and 2,6- TDA 10,500 kkg
3,4-TDA 525 kkg
Because of the high concentrations of these constituents
and because these constituents are all acute and/or chronic toxicants
(see Section V.E.), a serious potential hazard is presented by their
release into the environment. These constituents moreover, are all
mobile in the environment (based on their solubilities in water and
other solvents), and some are expected to be persistent (see Section
V.D.); in addition, they are generated in large quantities. Therefore,
they are likely to enter into, and remain in the environment if there
is improper management, posing substantial risk. These considerations
justify a hazardous waste listing.
6) Waste No. K116, Organic condensate from the solvent
recovery column in the production of toluene diisocyanate via
phosgenation of toluenediamine.
This waste is expected to contain significant concentra-
tions of carbon tetrachloride, tetrachloroethylene, chloroform,
and phosgene. All of these, except phosgene, have been identified
32
-------
as potential human carcinogens by the Agency's CAG; in addition, they
are chronically toxic. Phosgene is extremely dangerous as an acute
toxicant at low concentrations in air. All of these constituents
are currently listed in 40 CFR Appendix VIII. (See Section V.B. for
discussion of toxic levels.)
A total of 150 kkg of this waste is expected to be generated
annually, based on 1980 production figures, with carbon tetrachlonde
constituting up to 75%, tetrachloroethylene up to 15%, chloroform
up to 7%, and phosgene up to 30%. Thus, there is a potential for the
escape of these constituents into the environment from waste K116 up
to the following amounts (based on the higher concentration limit):
Carbon tetrachloride 113 kkg
Tetrachloroethylene 23 kkg
Chloroform 11 kkg
Phosgene 45 kkg
Carbon tetrachloride, tetrachloroethylene, chloroform, and
phosgene are all volatile, and, at such high concentrations, may
result in inhalation exposure. In addition, although their solubility
is limited, they have been shown to migrate into the environment; also,
they are persistent in aqueous environments, and mismanagement of this
waste could result in significant human exposure by this route as well.
In fact, all of these toxicants (except phosgene) have been detected
in various samples at the Love Canal site (U.S. EPAd, 1980), demonstra-
ting their mobility and persistence in the environment.
A further risk to human health and the environment may be posed
by improper incineration of these compounds. Improper incineration
33
-------
of the chlorinated hydrocarbons, including carbon tetrachloride,
tetrachloroethylene, and chloroform could cause exposure to unburned
toxicants in the wastes, and exposure to products of incomplete
combustion, including phosgene and hydrochloric acid.
Therefore, because of the high concentrations of these
toxicants in the waste, and their ability to migrate and persist
in the environment, a serious potential hazard is presented by
their release into the environment. These considerations justify
a hazardous waste listing.
B. Degree of Hazard of These Wastes
The Agency has determined that several of the hazardous
constituents in these wastes are toxic. For example, the Agency's
Carcinogen Assessment Group (CAG) has determined that 2,4-TDA and
o-toluidine are potential human carcinogens; several of these toxi-
cants are experimental mutagens; and several are reproductive or
teratogenic toxins, or otherwise cause chronic or acute systemic
effects.
A semi-quantitative assessment was made of the degree of
hazard posed by these wastes, if mismanaged. For each constituent
of concern, an allowable daily intake (ADI), or the 10~6 excess
cancer risk level virtually safe dose (VSD) was calculated (see
Appendix I). The methods used for these calculations are those
used to calculate Water Quality Criteria (U.S. EPAf, 1980). These
doses are listed in column 5 of Table 5. 2,6-DNT and 2,6-TDA
have other chronic systemic effects. For these chemicals an ADI
was estimated from animal studies (U.S. EPAf, 1980).
34
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TABLE 5
WASTE
Kill
K112
K113
K114
K115
K116
TOXICANT
OF
CONCERN
(TOG)
2,4-DNT
2,6-DNT
2,4- + 2,6-TDA
3,4-TDA
o-toluidine
Pj-toluidine
2,4- + 2,6-TDA
3,4-TDA
aniline
o-toluidine
pj-toluidme
2,4 + 2,6-TDA
3,4-TDA
o-toluidine
£-toluidine
2,4 + 2,6-TDA
3,4-TDA
Carbon
tetrachloride
Tetrachloro-
ethylene
Chlorofonn
(TOC) /Waste
%
0.08
0.02
0.03
0.03
0.06
0.04
37.5
37.5
0.1
6
4
47.5
2.5
3
2
50
2.5
up to 75
up to 15
up to 7
Estimated
Daily
Exposure
(DE)
mg/day3
0.030
0.007
0.10
(0.05)c
0.10
0.02
0.013
12.5 (6.3)c
12.5
0.03
2
1.3
16 (8)c
0.8
1
0.7
13 (6.5)c
0.8
25
5
2.3
ADI, (A) or
VSD, (V) at
the 10~6 Cancer
Risk Level
rag/day13
2.6 x 10-4 (V)
2.1 (A)
3 x 10~6 (V)
-
2.9 x ID"4 (V)
-
3 x 10-6 (V)
-
2.3 x ID"3 (A)
2.9 x 10~4 (V)
-
3 x 10~6 (V)
-
2.9 x ID"4 (V)
-
3 x ID'6 (V)
-
8.5 x ID"4 (V)
18 x 10-4 (V)
3.8 x ID"4 (V)
DE/
ADI
or
VSD
100
10-3
104
-
700
-
2 x 106
-
13
0.7 x!04
-
3 x 106
-
3000
-
2 x 106
-
3 x 104
2.5 x 103
5 x 103
b "-" = NO ADI for cancer potency estimate available,
c If 50% of the reported mixture is 2,4-TDA.
35
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For each toxicant of concern, a daily exposure dose was
estimated by use of the plausibly-occurring mismanagement scenario
outlined in Appendix I. The resulting values are listed in column 4
of Table 5. For each toxicant, a crude estimate of the risk of chronic
systemic or carcinogenic effects was obtained by comparing this estimated
daily exposure with the ADI or VSD. These comparisons are shown in
column 6 of Table 5.
Ambient Water Quality Criteria (AWQC) have been established
(see 45 FR 79318, November 28, 1980) for four of the toxicants of
concern in the wastes which we are proposing to list, namely, 2,4-DNT;
carbon tetrachloride; tetrachloroethylene; and chloroform. The AWQC
developed for these substances to protect against a 10"^ excess
cancer risk to humans resulting from the consumption of water and
aquatic organisms are 0.11, 0.4, 0.8, and 0.19 ug/1, respectively.
As seen in Table 5, these toxicants are present in the wastes
at concentrations 107 - 109 times higher than the AWQC; in addition,
their solubility is many times greater than the AWQC. Thus, even
though soil attenuation factors, such as soil binding, biodegradation,
and other environmental degradative processes are expected to decrease
the amount of the toxicants available for migration, these toxicants
are expected to present a substantial hazard, since only a small fraction
need migrate from the wastes and reach environmental receptors to pose
the potential for substantial harm.
The Agency thus concludes that the concentrations of 2,4-DNT,
2,4- and 2,6-TDA, o-toluidine, carbon tetrachloride, tetrachloro-
ethylene and chloroform may occur in the listed wastes at levels
of regulatory concern.
36
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Although the Agency was not at this time able to make a quali-
tative evaluation of the levels of concern for 3,4-TDA and p_-toluidine,
we believe that the toxic effects of these substances (see Section V.E.)
are such as to warrant their designation as toxicants of concern.
In the case of aniline and 2,6-DNT, the ratio of estimated
to allowable daily exposure is not high. However, the Agency judges
that their toxic properties, and their demonstrated persistence
(i.e., they have been found in ground and surface water and/or soil),
provide sufficient grounds to warrant their inclusion.
C. Mismanagement
A number of environmental damage incidents have occurred
due to mismanagement of either DNT, TDA, or TDI wastes, or other
wastes containing the hazardous constituents found in wastes from
DNT, TDA, or TDI production. These incidents show either that these
wastes can cause substantial harm if mismanaged, or that the
constituents of concern are mobile and persistent upon migration.
DNT waste products have been discharged into surface water
or sewage by industries that manufacture dyes, isocyanates, polyur-
ethanes, and munitions. As a result of the routine discharge to
surface waters of its plant process water containing residues of
DNT by the Milan Army Ammunition Plant in Milan, Tennessee, wells
in the installation in the vicinity of the industrial lagoons
were found to have residues of DNT (U.S. EPAc, 1980).
2,4-DNT has been detected both in ambient waters and in
industrial effluents (U.S. EPAe, 1979).
37
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In Abbeville, LA, groundwater was found to be contaminated
by a number of substances, including 2,4-DNT at a concentration
of 31 ug/1, about 280 times the AWQC level. Twenty-two wells exist
within 1/4 mile of the site; the distance to the drinking water
supply is 300 yards. The source of the contamination is an open pit
for disposal of oil-based mud and storage tanks.
2,6-DNT has been detected in the water effluent of a tri-
nitrotoluene plant in Virginia, in pond effluent of a DNT plant,
as well as in tap water in the united States,
indicating both the mobility and the persistence of DNT in the
environment (U.S. EPAa, 1980).
Both o- and £-toluidines have been detected in quite a
few samples of ground water and surface water, as well as in
chemical plant effluents (U.S. EPAa, 1980).
An industrial facility allegedly dumped sludge from aniline
production in two open pits prior to 1952. In subsequent years, the
the area was used for waste disposal until the site was closed in
July, 1974. Surface water, groundwater, and soil are suspected to be
contaminated by aniline.
In measurements made during the National Organics Monitoring
Survey of 113 public water systems sampled, 11 of these systems
detected carbon tetrachloride at levels at or exceeding the recommended
safe limit. Carbon tetrachloride has also been detected in school and
basement air samples taken at the Love Canal site (U.S. EPAd, 1980).
Tetrachloroethylene has been detected in school and basement
38
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air, basement sumps, and solid surface samples at Love Canal
sites (U.S. EPA, 1980d). It has been detected in a number of
drinking water samples (U.S. EPAa, 1980).
Chloroform has been detected in basement sumps and school
and basement air at the Love Canal site (U.S. EPAd, 1980).
(A large number, more than 60, of additional damage
incidents relating to contamination by carbon tetrachlonde,
tetrachloroethylene, and chloroform are appended to this listing
Background Document.)
Thus, if waste disposal sites are improperly designed or
managed - for example, sited in areas with highly permeable soils or
constructed without effective natural or artificial liners - there
is a possibility of escape of waste constituents to ground water or
surface water, and, in the case of the volatile constituents, to
the atmosphere as well.
A further possibility of substantial hazard arises during
transport of these wastes to off-site disposal facilities. The
damage incidents described above in fact demonstrate hazards which
may arise during off-site transportation and management. Some of
the toxicants of concern in these wastes are persistent, biodegrade
slowly, and can thus cause substantial harm to human health and
the environment (see Section V.D.).
Another risk to human health and the environment may be
posed by improper incineration of some of these compounds. Improper
incineration of the chlorinated hydrocarbons, including carbon
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tetrachloride, tetrachloroethylene, and chloroform could cause exposure
to unburned toxicants in the wastes, and exposure to products of
incomplete combustion, including phosgene and hydrochloric acid.
D. Environmental Effects of the Hazardous Constituents
The environmental effects described here are more fully
discussed in the Health and Environmental Effects Profiles.8
Dinitrotoluenes (DNT) would be expected to biodegrade to a
limited extent. The nitro groups retard biodegradation and studies
with soil microflora have shown that mono- and di- substituted nitro-
benzenes persist for more than 2 months (U.S. EPAa, 1980). It has
been reported that dinitrotoluenes are decomposed very slowly in
a reservoir; biodegradation by Azotobacter has also been reported
to be slow (U.S. EPAe, 1979).
As indicated by the solubility of 2,4-DNT (270 mg/1 in
water at 22°C; readily soluble as well in ethanol, ether and carbon
disulfide (U.S. EPAa, 1979) and of 2,6-DNT (soluble in ethanol),
DNTs (constituents of waste Kill), if inadequately disposed, may
be dissolved found within mixed wastes and leach out of these
wastes into the ground water, causing a contamination problem,
especially since they are not readily biodegradable, so are
likely to persist.
The toluenediamines (TDA) are constituents of wastes
K112, K113, K114, and K115. 2,4-TDA is very soluble in hot water,
alcohol, and ether; 2,6-TDA is soluble in water and alcohol; and
8These documents are available in the RCRA Docket, and at EPA
regional libraries.
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3,4-TDA is very soluble in water (CRC, 1968). Although monitoring
data are not available for these substances, they are capable of
causing water contamination problems by being dissolved within
mixed wastes, and leaching out of these wastes into waterways,
from improperly designed and managed waste disposal sites.
Some studies have shown that o- and £-toluidine would not
significantly biodegrade by activated sludge in a week, although
aniline activated sludge and £-nitroaniline activated sludge
degraded them (U.S. EPAa, 1980).
In the absence of adequate data, it is difficult to
estimate the half-life of the toluidine biodegradation in ambient
aquatic media. However, the fact that both isomers have been
detected in quite a few samples of ground water and surface
water (U.S. EPAa, 1980), demonstrates both the mobility and
persistence of the toluidines.
Aniline is very water soluble (35,000 ppm at 25°C)
(U.S. EPAb, 1980). Soils of organic content may retain aniline;
clays of high surface area (montmorillonite) will also have some
retention capacity (U.S. EPAa, 1980). Aniline has a low vapor
pressure of 1 mm Hg at 35°C and 10 mm Hg at 70°C (U.S. EPAa,
1980), so it is unlikely to volatilize from water or soil into
the atmosphere. All of these factors contribute to aniline's
potential persistence in the environment.
Carbon tetrachloride, a constituent of waste K116, is
very soluble in water (800 mg/1 at 20°C, Verschueren, 1977). It
is nondegradable in water, with a hydrolytic breakdown half-life
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of 70,000 years, and tends to remain indefinitely at the bottom of
water courses (U.S. EPAb, 1980). It is also extremely volatile (90
mm Hg at 20°C, Verschueren, 1977), and therefore, could present
an inhalation hazard. In the incineration of carbon tetrachloride-
containing wastes, phosgene, a highly toxic gas, is emitted under
incomplete combustion conditions. All of these factors demonstrate
that carbon tetrachloride is both mobile and extremely persistent
in the environment.
Tetrachloroethylene, another constituent of waste K116,
is volatile (vapor pressure = 37.6 mm Hg at 40°C). Its water
solubility is 150 mg/1, and it has been detected in a number of
drinking water samples (U.S. EPAa, 1980). All of these factors
demonstrate that tetrachloroethylene is both mobile and very
persistent in the environment.
Chloroform, a constituent of waste K116 , is also very
mobile and persistent in the environment. it is very water-
soluble (8,200 mg/1, U.S. EPAe, 1979), and also very volatile,
with a vapor pressure of 200 mm Hg at 25°C (U.S. EPAa, 1980).
Chloroform is stable under normal environmental conditions.
When exposed to sunlight, it decomposes slowly in air, but is
relatively stable in water. The measured half-life for hydrolysis
was found to be 15 months (U.S. EPAa, 1980).
Phosgene, also found in waste K116, has high acute
toxicity and has been used as a nerve gas by the military. It
is extremely volatile (1215 mm Hg at 20°C). It is only slightly
soluble in water (Windholz, 1976) and would most likely volatilize
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from wastes, causing an air pollution problem if not properly
contained on disposal.
E. Health Effects of the Hazardous Constituents
1. Dinitrotoluenes
a. 2,4-Dinitrotoluene (2,4-DNT) is absorbed by ingestion,
inhalation, and through the skin. The EPA's Carcinogen Assessment Group
(CAG) determined that 2,4-DNT is a potential human carcinogen, inducing
liver and kidney carcinoma and (benign) mammary tumors in rats and
mice. 2,4-DNT is mutagenic in several assay systems. Chronic
exposure causes decreased sperm production and testicular atrophy
in rats, and may produce methemoglobinemia, anemia, jaundice, and
liver damage in animals and humans; alcohol aggravates its toxic
effects. In addition, the oral toxicity hazard of 2,4-DNT is
very high (Sax, 1979).
The Occupational Safety and Health Administration (OSHA)
has set the permissible exposure limit (PEL) for 2,4-DNT in air
at 1.5 mg/m3 as the time-weighted average (TWA).
The Ambient Water Quality Criterion to protect humans from
the effects of 2,4-DNT has been set at 0.11 ug/1. A 24-hour average
concentration of 620 ug/1, not to exceed 1,400 ug/1, has been set
as the EPA's Water Quality Criterion to protect freshwater life
from the toxic effects of 2,4-DNT. 2,4-DNT is a priority pollutant
under Section 307(a) of the Clean Water Act (CWA).
b. 2,6-Dinitrotoluene (2,6-DNT) is absorbed by ingestion,
inhalation, and through the skin. it produces benign tumors in rats,
and is mutagenic in several strains of Salmonella typhimurium without
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metabolic activation. it causes metheraoglobinemia in cats, dogs,
rats, and mice. When administered orally to these animals for a
maximum of thirteen weeks, the major effects seen, in addition to
the blood effects, were depressed spermatogenesis, liver and
kidney degeneration, bile duct hyperplasia, and incoordination
and rigid paralysis of the hind legs. 2,6-DNT is listed as
having a high toxicity via ingestion (Sax, 1979).
The OSHA PEL for 2,6-DNT in air is 1.5 mg/m3 (TWA).
2,6-DNT is a priority pollutant under Section 307(a) of
the CWA.
2. Toluenediamines
a. 2,4-Toluenediamine (2,4-TDA) is absorbed by ingestion,
inhalation, and through skin contact. It is carcinogenic in rats
and mice. 2,4-TDA has been identified by the Agency's CAG as a
potential human carcinogen. It is a frameshift mutagen in bacterial
and insect test systems, and causes cell transformation. The results
of a dominant lethal test, however, were negative. 2,4-TDA is
hepatotoxic to rats and mice, and causes renal disease.
2,4-Toluenediamine has also been designated as moderately
toxic when inhaled (Sax, 1979).
There are no Federal guidelines or standards for exposure
to 2,4-TDA.
b. 2,6-Toluenediamine (2,6-TDA) is positive in the Ames
Salmonella assay system in the presence of enzyme activators, as
well as in a cell transformation system. Reduced weight gain,
nephrosis, and hyperplasia were found in rats and mice administered
3,000 - 10,000 ppm of 2,6-TDA in the diet for 3 months. Among these
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animals, diffuse bilateral adenomatous hyperplasia of the thyroid
was seen in 70% of male rats fed 3000 ppm. At lower dose levels,
other studies have not identified adverse effects.
c. 3,4-Toluenediamine (3,4-TDA) produces positive
mutagenic response in some assay systems. Female rats receiving
33.3 or 50 mg/100 kg body weight of 3,4-TDA by gavage twice
daily for 5 days developed duodenal ulcers; single subcutaneous
injections of 62.5 - 500 mg/kg of 3,4-TDA to male and female
rats resulted in gastric and duodenal lesions.
3. Toluidines (aminoroethylbenzenes)
a. o-Toluidine (2-amino-l-methylben2ene) is absorbed
both orally and dermally. o-Toluidine is metabolized, and excreted
mainly through urine. it has been identified by the Agency's CAG
as a potential human carcinogen. In the Ames test, o-toluidine
only exhibits a positive mutagenic response when a special "activator"
is added. There is evidence of transplacental migration of o-toluidine
or its metabolites. Induction of fetal tumors has also been observed.
Other chronic effects observed experimentally are bladder lesions
and other bladder abnormalities, methemoglobinemia, sulfhemoglobinemia,
and increased levels of cytochrome oxidase. o-Toluidine has also
been designated as highly toxic via oral, and moderately toxic
by dermal routes of exposure (Sax, 1979).
The OSHA PEL for o-toluidine is 5 ppm in air (TWA).
The American Conference of Governmental Industrial
Hygienists (ACGIH) recommends an 8-hour threshold limit value
(TLV) at 2 ppm (TWA).
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b. p-Toluidine (4-amino-l-methylbenzene) is absorbed by
ingestion and dermally. It is metabolized, and excreted primarily
in the urine. 2~Toluidine nas been tested for carcinogenicity in
male rats and in female mice, and increased the incidence of hepatoma
in mice only. £-Toluidine caused methemoglobineraia in cats when
intravenously injected. p_-Toluidine has also been designated as
highly toxic by ingestion (Sax, 1979).
The FDA has established a tolerance of 0.1% for p_-toluidine
in D and C green dye No. 6.
4. Aniline is absorbed orally, dermally, and through inhala-
tion. It is rapidly absorbed into the blood stream and metabolized
in the liver. The metabolites are excreted in the urine. Aniline
is carcinogenic in rats, with statistically significant increases
of fibrosarcomas and sarcomas of the spleen and in multiple body
organs. Aniline can cross the placental barrier and form methemo-
globin in the fetus, affecting its development. Aniline also has a
number of chronic effects, including methemoglobinemia and anemia.
At higher exposure levels, cardiotoxic effects, hepatic injury,
splenic hemosiderosis, fatigue, headache, irritability, dizziness,
insomnia, and paresthesias are noted. Aniline has been designated
as highly toxic through oral and inhalation routes of exposure
(Sax, 1979).
The maximum allowable concentration in class I waters
used for drinking water in the U.S. is 5 mg/1.
5. Carbon tetrachloride has been identified by the
Agency's Carcinogen Assessment Group (CAG) as a potential human
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carcinogen. Retarded fetal development, fetal liver changes,
and slight fetotoxicity have been demonstrated in rats. Chronic
effects include fatigue, lassitude, giddiness, anxiety, headache,
paresthesias, muscular twitching, increased reflex excitability,
moderate jaundice, hypoglycemia, anorexia, nausea, diarrhea, mild
anemia, cardiac and kidney pain, dysuria, slight nocturia, and
blurred vision. Adverse effects of carbon tetrachloride on liver
and kidney functions and on the respiratory and gastrointestinal
tracts have also been reported. Death has been caused in humans
at small doses. Obese individuals are especially sensitive to
the toxic effects of carbon tetrachloride. Carbon tetrachloride
is considered a high systemic poison hazard through ingestion
and inhalation (Sax, 1979).
The OSHA PEL for carbon tetrachloride in air is 10 ppm (TWA).
The Ambient Water Quality Criteria for carbon tetrachloride
designed to reduce the excess human cancer risk is 0.4 ug/1.
Carbon tetrachloride is a priority pollutant under Section
307(a) of the CWA.
6. Tetrachloroethylene has been identified by the Agency's
CAG as a potential human carcinogen. it is a mutagen in bacterial
assays. It is also chronically toxic to dogs, causing kidney and
liver damage, and to humans, causing impaired liver function. In
mice and rats, tetrachloroethylene has caused toxic nephropathy.
Subjective central nervous system complaints were noted in workers
occupationally exposed to tetrachloroethylene. Exposure to tetra-
chloroethylene is reported to cause alcohol intolerance to humans.
Tetrachloroethylene is designated as moderately toxic by
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inhalation, oral, subcutaneous, intraperitoneal, and dermal routes,
and highly toxic via the intravenous route of exposure (Sax, 1979).
The AGCIH TLV for tetrachloroethylene in air is 670 mg/m3.
The Ambient Water Quality Criterion for tetrachloroethylene
designed to reduce the excess human cancer risk is 0.8 ug/1.
The Water Quality Criterion to protect saltwater aquatic
life from the toxic effects of tetrachloroethylene is 79 ug/1 as a
24-hour average, not to exceed 180 ug/1 at any time; for freshwater
aquatic life, the the draft criterion is 310 ug/1 as a 24-hour
average, not to exceed 700 ug/1 at any time. Tetrachloroethylene
is a priority pollutant under Section 307(a) of the CWA.
7. Chloroform has been identified by the Agency's CAG as
a potential human carcinogen. Chloroform induces hepatocellular
carcinomas in mice, and kidney epithelial tumors in rats. It is
also a teratogen: chloroform induces fetal'abnormalities (acaudia,
imperforate anus, subcutaneous edema, missing ribs, and delayed
ossification) in rats. In addition, it is fetotoxic to rats and
rabbits. Other chronic effects include liver necrosis and kidney
degeneration. It is absorbed by ingestion, inhalation, and dermally.
A small fraction of absorbed chloroform is metabolized by mammals.
Alcohol, and high fat and low protein diets reportedly enhance
the toxic effects of chloroform. Chloroform is designated as
moderately toxic by oral and inhalation routes (Sax, 1979).
The OSHA PEL for chloroform in air is 2 ppm (TWA).
The FDA prohibits the use of chloroform in drugs, cosmetics,
or food contact material.
The Ambient Water Quality Criterion for chloroform designed
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to reduce the excess human cancer risk is 0.19 ug/1.
The Ambient Water Quality Criterion for chloroform to
protect freshwater aquatic life is 500 ug/1 (24-hour average),
not to exceed 1,200 ug/1 at any time. To protect saltwater
aquatic life, the criterion is 620 ug/1 (24-hour average), not to
exceed 1,400 ug/1 at any time. Chloroform is designated a priority
pollutant under Section 307(a) of the CWA.
8. Phosgene (this discussion is taken from sax, 1979) is
highly toxic by inhalation and highly irritating to the eyes and
mucous membranes. Within the lungs, phosgene decomposes to carbon
monoxide and hydrochloric acid. Because there is little irritation
to the respiratory tract, its warning properties are very slight.
The liberation of hydrochloric acid in the lung tissues results
in pulmonary edema, which may be followed by bronchopneumonia,
and occasionally lung abcess. Degenerative changes in the nerves
have also been reported.
Concentrations of 3 - 5 ppm phosgene in air causes irrita-
tion of the eyes and throat, with coughing; 25 ppm is dangerous
for exposure lasting 30 - 60 minutes, and 50 ppm is rapidly fatal
after even short exposure. There may be no immediate warning
that dangerous concentrations are being breathed. After a latent
period of 2 - 24 hours, the patient complains of burning in the
throat and chest, shortness of breath and increasing dyspnea.
There may be moist rales in the chest. Where the exposure was
severe, the development of pulmonary edema may be so rapid that
the patient dies within 36 hours after exposure. In cases where
the exposure was less, pneumonia may develop within several
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days. In patients who recover, no permanent residual disability
is thought to occur.
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VI. References
^1 R~uber ComPany- Handbook of Chemistry and Physics.
ed. The Chemical Rubber Company, Cleveland, OH. 1968.
?*!!' *' Ifvin9- Dangerous Properties of Industrial Materials.
5tn ed. van Nostrana Reinhold Co., New York. - 1979. -
S-Cubed. Analysis of RCRA Solid Wastes from the Industria
Organic Chemicals inaustrv; Toluene Diisocyanate. -prSTTST
. narv
INFORMATION^ °A' September' 1983' (CONFIDENTIAL BUSINESS
nco °ufiCe x°f S°lld WaSte' Hazardous and Industrial Waste
Division. Hazardous Waste Incidents (unpublished, open file).
U.S. EPAa. Office of Solid Waste. Appendix A - Health and
Environmental Effects Profiles. Washington, B.C. October 30,
1980, and subsequent revisions.
U.S. EPAb. Office of Solid waste. Appendix B - Physical
1C Constituents! "W^hlnntnn ,
?' ^ri'Th^AC; 211 a"d SPecial Materials Control Division. Damages
u"?i. Caused by Hazardous Material Sites. EPA/430/980/004.
Washington, D.C. May 1980. -- /»ou/uui.
8* nA?' EPAd\ Genfric Chlorinated Organic Waste Streams. Background
Document, Appendix D. Washington, D.C. - T980: - Kgrouna
Office ,?f Water. Water-Related Environmental Fate
P°11UtantS ^olume II). Washington, D.C. -
10' 2:?o EnAfi'-.°fJ1Ce °f Water Ouality Regulations and Standards.
Water Quality Criteria. 45 Federal Register 79318-79379
Washington, D.C. November 28, 1980. -
11. U.S. EPAg. Office of Solid Waste. Solid Waste Data: A Compil-
P^^^^^ Management Within ^niL*
12 ' XS!?!!11!!;*11',,*";1' Ha"dbo°k of Environmental Data on Organic
Nostrand Reinhold Co., New York. - 1977. — -
Merck Inde'" 9th ed-
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Appendix I
MISMANAGEMENT SCENARIO
The wastes under consideration are assumed to constitute 5%
of the wastes disposed in a sanitary landfill receiving predominantly
domestic refuse. The mean density of the refuse is 415 kg/m3 (U.S.
EPAg, 1981), and the depth of the landfill is assumed to be 6 meters
(20 feet). Therefore, per square meter of the landfill, there are
121 kg of the industrial waste (0.05 x m2 x 6m x 415 kg/m3). Rain-
fall, estimated at 1000 l/m2/year (U.S. EPAg, 1981), is estimated to
migrate through the landfill. AS a worst case, it is assumed that
all of the toxicant contained in the industrial waste dissolves
in the rainfall percolating through the landfill over its 70-year
operational lifetime. Thus, if the waste contains 0.08% of a
toxicant, the toxicant available for leaching per square meter
of landfill (0.08 kg toxicant/100 kg waste x 127 kg waste x 106
mg/kg = 1.02 x 105 mg) is dissolved in 70 x 103 liters of leachate,
resulting in an average concentration of 1.46 mg toxicant per liter
of leachate. Assuming a 100-fold attenuation between the generating
site and a ground water, the drinking water concentration would be
0.015 mg/1. The estimated daily intake of a person drinking this
water would be 0.015 mg/1 x 2 I/day = 0.030 mg/1. These estimated
exposures are listed in column 4 of Table 5.
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