*• WLB:TDI1:01 iffy
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 hydrogenation of dinitrotoluene (T)
K113:. Light ends from the purification of toluenediamine in the production of toluenediamine via hydrogenation . .'. of dinitrotoluene (T)
-. ..K114V Vicinals from the purification of toluenediamine l'__ , ; in the production of toluenediamine via hydrogenation \ ' of dinitrotoluene (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 "i production) was previously listed. A background document for Vl' this listing has been available in the public docket at EPA L^ Headquarters and at EPA regional libraries since May 19, 1980. H
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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) 3
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 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 (TDA), and from the reaction of TDA with phosgene to form toluene diisocyanate (TDI), are hazardous solid wastes. The
Administrator has determined that wastes from the above processes 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. This 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 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 Wastes2
A. Profile of the Industry
The manufacture of toluene diisocyanate (TDI) from toluene involves the production of dinitrotoluene (DNT) and toluenediamine
(TDA) 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. TABLE 1 - PRODUCERS OF TOLUENE DIISOCYANATE (TDI)1
RAW CAPACITY3 PRODUCER MATERIAL PRODUCTS2 (106 kg/yr)
Mobay Chemical Corp. toluene 1,2,3 59 Baytown, TX
Mobay Chemical Corp. toluene 1,2,3 57 New Martinsville, WV
Olin Corp. dinitro 2 45 Lake Charles, LA toluene
Olin Corp. toluene 2 34 Moundsville, WV
BASF Wyandotte Corp. -dinitro .2 57 Geismar, LA toluene
Dow Chemical toluene 2 45 Freeport, TX diamine
Rubicon Chemicals toluene 2 18 Geismar, LA
TOTAL 315 ionly manufacturers of TDI are listed within this table. Other manufacturers produce DNT and/or TDA intermediates but do not produce TDI (see text). 2Rey 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). domestically in 1980, 1981, and 1982. Reported production data
for DNT and TDA 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 TDA (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 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 (Q) +2HN03 H2S°4 * Gi— (N02)2 + 2H20 •oluene "llVS Dinitrotoluene C (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 Vent Gas Washwater
n Kill
_ DNT Product
HNO3 *-
H2S04
Acid Recovery Water
Piqure 1. Typical Process Flow Diagram for the Nitration ot Toluene 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 o*i 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 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 CH3 (N02)2 +8H2 Catalyst, fg}— Dinitrotoluene Toluene Diamine (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 identical 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 hydroxylamine (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 < I I I 2,5-DNT 2,4-DNT 2,67DNT 3,4-DNT 2,3-DNT 0.52 11% 19% 2.5% 1.0% Figure 2. Isomer Production in the Nitration of Toluene © By-Rroduct Water Vicinals K112 K114 TDA Product Recycled 0 Solvent e c Make-Up E E Solvent Catalyst 3 O O O O c E ' c >» o J- Catalyst O DNT Reactor > o -6- t- 6 Recovery o a> Figure 3. Typical Process Flow Diagram for the Hydrogenation of*DNT to TDA 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 The fourth distillation column separates out the toluenediamines 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 reduced 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 CH3 (Gj— (NHo)2 +2C0C12 ^ (0)—(NC0)2 +4HC1 Tol u-ene Phosgene Toluene Diamine Diisocyanate (TDA) (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 Vent Gas-*--, r\ Vent Gas Water Phosgene Recycle HCl Soluti in (Coproduct) Product TDI © CO Phosgene Solution Phosgene — TDI Residue Phosgene Recycle K027 Figure 4. Typical Process Flow Diagram for the Manufacture of TDI from TDA + C0C1 2 Toluene-2, Phosgene 3-Diamine (Methyl-benzimidazolone) In addition, the imidazolone combines with TDI, forming intractable sludges, which present physical removal problems. Therefore, the TDA feed to this process is usually of very high isomeric purity; it consists of an 80:20 (+ 1%) 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 HCl 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 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 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 Wastes^ 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 acids (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-£-cresol); mononitrotoluenes (about 0.005%); and mononitrophenols, dinitrophenols, nitrobenzoic acids, and 3see footnote 2. 16 monon itrocresols (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 o-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 £-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 TABLE 2: APPROXIMATE AVERAGE COMPOSITION OF DNT WASHWATER1 Constituent Concentration (ppm) Dinitrotoluenes 1085 (see Figure 2 for approximate isomer distribution) Mononitrotoluenes 45 (see Figure 2 for approximate _ isomer distribution) Dinitrocresols 600- (mostly 2,6-dinitro-£-cresol) Nitrophenols 35 (including di- and mono-nitrophenols) Other nitroaromatics, including 35 nitrobenzoic acids and nitrocresols TOTAL ORGANICS 1800 . 1q-S-CUBED, 1983 18 TABLE 3: COMPOSITION OF MAJOR WASTE STREAMS FROM PLANTS THAT MANUFACTURE DNT, TDA & TDI WASTE STREAM MAJOR CONST]:tuents * ESTIMATED DESIGNATION DESCRIPTION TYPE CONSTITUENT CONCENTRATION (Figs. 1,3,4) RANGE (%) Kill DNT Washwater Aqueous Dinitrotoluenes, 0 - 0.3 liquid Nitrophenolics (pH=l-2) Inorganics* 1-4 H2SO4 + HNO3 Sulfate + Nitrate Salts K112 Byproduct water frcm Aqueous Toluenediamines 0.1 - 0.6 the TDA drying column liquid 2,4-TDA & 2,6-TDA 0.05 - 0.3 3,4-TDA (& 2,3-TDA) 0.05 - 0.3 Toluidines 0 - 0.1 o-toluidine 0 - 0.06 £-toluidine 0 - 0.04 K113 Light ends frcm the Organic Toluenediamines 0-75 purification of liquid 2,4-TDA & 2,6-TDA 0 - 37.5 crude TDA 3,4-TDA (& 2,3-TDA) 0 - 37.5 Toluidines 1-10 o-toluidine 0.6 - 6 £-toluidine 0.4 - 4 Aniline 0.01 - 0.1 K114 Vicinals frcm the Viscous Toluenediamines 0-95 purification of organic 2,4-TDA & 2,6-TDA 4.5 - 50 crude TDA liquid/ 3,4-TDA (& 2,3-TDA) 45 - 95 solid Toluidines 0-5 o-toluidine 0-3 £-toluidine 0-2 K115 Heavy ends frcm the Viscous Toluenediamines 10 - 50 purification of organic 2,4-TDA & 2,6-TDA 10 - 50 crude TDA liquid 3,4-TDA (& 2,3-TDA) 0 - 2.5 Spent Catalyst (Ni) 0-5 K116 Organic liquid con Organic Carbon tetrachloride 0-75 taining chlorinated liquid Tetrachloroethylene 0-15 hydrocarbon impurities Chloroform 0-7 Phosgene 0-30 K0272 Heavy ends frcm the Viscous Polymerized TDI 50 - 100 purification of organic TDI 0-50 crude TDI liquid | •'•Inorganic conposition varies between plants depending on the degree to which acids (H2S04 + HNO3) in the crude DNT product are neutralized by alkaline washwaters. 2This waste is currently regulated in.40 CFR 261.32. 19 (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 polymeries 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 TDI 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 COMPONENT CONCENTRATION (%) Isocyanurates (TDI trimer) 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. 6The listing background document for EPA Hazardous Waste No. K027 estimated a slightly different composition for this waste. 21 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 7See footnote 2. 22 TABLE 4: SUMMARY OF QUANTITY AND MANAGEMENT DATA FOR MAJOR WASTE STREAMS FROM PLANTS THAT MANUFACTURE DNT, TDA & TDI • WASTE MANAGEMENT GENERATION RATE TOTAL ESTIMATED DESIGNATION (kg of wasteAg TDI GENERATION1 SEQUENTIAL TECHNIQUES USED2 USE (%)3 Produced) (kkg/yr) Kill 1.1 - 2.0 427,000 NTRL, BIOL, CRBN, DSWR 60 NTRL, CRBN, STLG, DSWR 11 SIMP, DWI 4 Unknown 25 K112 0.44 - 1.23 195,000 NTRL, BIOL, CRBN, DSWR 27 BIOL (SIMP), DSWR 29 CTRT, CRBN, NTRL, DSWR 19 SIMP, DWI 4 Unknown 21 K113 0.004 - 0.012 240 SIMP, DWI 71 INCN 8 Unknown 21 K114 0.012 - 0.065 3,700 RCRY 23 MKTD 21 INCN-OFST 18 FUEL 17 Unknown 21 K115 0.02 - 0.25 21,000 INCN 76 LDFL-OFST 3 Unknown 21 K116 0.0003 - 0.007 150 INCN 100 K0274 0.09 - 0.28 21,000 INCN 35 ************************ ******** PILE, LDFL-OFST 18 FUEL 12 PILE, LDFL 1 4otal waste stream quantity generated in association with the production of TDI and intermediates, based on 1980 production figures. 2Key to management techniques: BIOL = Biological wastewater treatment CRBN = Carbon adsorption CTRI = 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 *******OONFIDENTIAL BUSINESS INFORMATION STLG = Settling SIMP = Surface impoundment Percentage of total generated waste treated by the sequence of techniques indicated. ^This waste is currently regulated in 40 CFR 261.32. 23 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. ************************************* 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 oti "cafborf is -suggested in the literature.- Due-t-6 the inherent value of the metal components in these catalysts, the spent catalyst is often reclaimed. -;.-"-'"""" Very little Hnfo'rma'tion -was -supplied by the manufacturers regarding spent activated" carbon quanti'-ti-es 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(f): U105, 2,4-dinitrotoluene; U106, 2,6-dinitrotoluene; U22T, 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 V. Basis for Listing A. Hazards Posed by the Wastes 1) Waste No. Kill, 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 (CAG); and 2,6-dinitrotoluene, an experimental muta gen (i.e., positive in ^iji 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 £-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 £-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 o- and £-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- TDA 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 the-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 £-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 £-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 p-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 tetrachloride 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 (ADD, 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 t CABLE 5 * - 4 Estimated ADI, (A) or WASTE TOXICANT- (TOC)/Waste Daily VSD, (V) at DE/ OF % Exposure the 10~6 Cancer ADI CONCERN (DE) Risk Level or (TOC) mg/day3 mg/dayD VSD Kill 2,4-DNT 0.08 0.030 2.6 x 10~4 (V) 100 2,6-DNT 0.02 0.007 2.1 (A) 1(T3 K112 2,4- + 2,6-TDA 0.03 0.10 3 x 10~6 (V) 104 (0.05)c 3,4-TDA 0.03 0.10 - - o-toluidine 0.06 0.02 2.9 x KT4 (V) 700 £-toluidine 0.04 - 0.013 - K113 2,4- + 2,6-im 37.5 12.5 (6.3)c 3 x 10-6 (V) 2 x 106 3,4-TDA 37.5 - 12.5 - aniline 0.1 0.03 2.3 x 10~3 (A) 13 o-toluidine 6 2 2.9 x.10-4 (V) 0.7 xlO4 £-toluidine 4 1.3 - - K114 2,4 + 2,6-TDA 47.5 16 (8)c 3 x 10~6 (V) 3 x 106 3,4-TTA 2.5 0.8 - - o-toluidine 3 1 2.9 x IO-4 (V) 3000 £-toluidine 2 0.7 - • - K115 2,4 + 2,6-TDA 50 13 (6.5)c 3 x 10~6 (V) 2 x 106 3,4-TDA 2.5 0.8 - - K116 Carbon up to 75 25 8.5 x IO-4 (V) 3 x 104 tetrachloride Tetrachloro up to 15 5 18 x 10~4 (V) 2.5 x 103 ethylene Chloroform up to 7 2.3 3.8 x 10"4 (V) 5 x 103 1 n~~ a - b "-M = No ADI for cancer potency estimate available, c if 50% of the reported mixture is 2,4-TDA. 35 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 10~6 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 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 £-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 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 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 tetrachloride, 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 39 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. 40 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 41 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 * 42 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 43 metabolic activation. It causes methemoglobinemia 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 ppra of 2,6-TDA in the diet for 3 months. Among these 44 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 (aminomethylbenzenes) a. o-Toluidine (2-amino-l-methylbenzene) 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). 45 b. p-Toluidine (4-amino-l-methylbenzene) is absorbed by ingestion and dermally. It is metabolized, and excreted primarily in the urine. £-Toluidine has been tested for carcinogenicity in male rats and in female mice, and increased the incidence of hepatoma in mice only. £-Toluidine caused methemoglobinemia in cats when intravenously injected. £-Toluidine has also been designated as highly toxic by ingestion (Sax, 1979). The FDA has established a tolerance of 0.1% for £-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 46 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 47 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 48 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 49 days. In patients who recover, no permanent residual disability is thought to occur. 50 VI. References 1. Chemical Rubber Company. Handbook of Chemistry and Physics, 48th ed. The Chemical Rubber Company, Cleveland, OH. 1968. 2. Sax, N. Irving. Dangerous Properties of industrial Materials, 5th ed. Van Nostrand Reinhold Co., New York. 1979. 3. S-Cubed. Analysis of RCRA Solid Wastes from the Industrial Organic Chemicals Industry: Toluene Diisocyanate. Preliminary draft. La Jolla, CA. September, 1983. (CONFIDENTIAL BUSINESS INFORMATION) 4. U.S. EPA, Office of Solid Waste, Hazardous and Industrial Waste Division. Hazardous Waste Incidents (unpublished, open file). 1978. 5.- U.S. EPAa. Office of Solid Waste. Appendix A- Health and Environmental Effects Profiles. Washington, D.C. October 30, 1980, and subsequent revisions. 6. U.S. EPAb. Office of Solid Waste. Appendix B- Physical Chemical Properties of Hazardous Waste Constituents. Washington, D.C. March, 1980. 7. U.S. EPAc. Oil and Special Materials Control Division. Damages and Threats Caused by Hazardous Material Sites. EPA/430/980/004. Washington, D.C. May 1980. 8. U.S. EPAd. Generic Chlorinated Organic Waste Streams. Background Document, Appendix D. Washington, D.C. 1980. 9. U.S. EPAe. Office of Water. Water-Related Environmental Fate of 129 Priority Pollutants (Volume II). Washington, D.C. December, 1979. 10. U.S. EPAf. Office of Water Quality 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 ation of Statistics on Solid Waste Management Within the United States. NTIS PB82-107301. 1981. ~" 12. Verschueren, Karel. Handbook of Environmental Data on Organic Chemicals, van Nostrand Reinhold Co., New York. 1977. 13. Windholz, Martha, ed. The Merck Index, 9th ed. Merck & Co., Inc., Rahway, NJ. 1976. 51 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/ra3). 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 1/day = 0.030 mg/1. These estimated exposures are listed in column 4 of Table 5. 52 1 , ." 9 Appendix II SELECTED DAMAGE INCIDENTS RESULTING FROM CONTAMINATION BY CARBON TETRACHLORIDE TETRACHLOROETHYLENE, AND CHLOROFORM 53